NASA Technical Reports Server (NTRS)
Beaudoing, Hiroko Kato; Rodell, Matthew; Ozdogan, Mutlu
2010-01-01
Agricultural land use significantly influences the surface water and energy balances. Effects of irrigation on land surface states and fluxes include repartitioning of latent and sensible heat fluxes, an increase in net radiation, and an increase in soil moisture and runoff. We are working on representing irrigation practices in continental- to global-scale land surface simulation in NASA's Global Land Data Assimilation System (GLDAS). Because agricultural practices across the nations are diverse, and complex, we are attempting to capture the first-order reality of the regional practices before achieving a global implementation. This study focuses on two issues in Southeast Asia: multiple cropping and rice paddy irrigation systems. We first characterize agricultural practices in the region (i.e., crop types, growing seasons, and irrigation) using the Global data set of monthly irrigated and rainfed crop areas around the year 2000 (MIRCA2000) dataset. Rice paddy extent is identified using remote sensing products. Whether irrigated or rainfed, flooded fields need to be represented and treated explicitly. By incorporating these properties and processes into a physically based land surface model, we are able to quantify the impacts on the simulated states and fluxes.
Center pivot mounted infrared sensors: Retrieval of ET and interface with satellite systems
USDA-ARS?s Scientific Manuscript database
Infrared sensors mounted aboard cener pivot irrigation systems can remotely sense the surface temperatures of the crops and soils, which provides important information on crop water status. This can be used for irrigation management and irrigation automation, which can increase crop water productivi...
Remote sensing based water-use efficiency evaluation in sub-surface irrigated wine grape vines
NASA Astrophysics Data System (ADS)
Zúñiga, Carlos Espinoza; Khot, Lav R.; Jacoby, Pete; Sankaran, Sindhuja
2016-05-01
Increased water demands have forced agriculture industry to investigate better irrigation management strategies in crop production. Efficient irrigation systems, improved irrigation scheduling, and selection of crop varieties with better water-use efficiencies can aid towards conserving water. In an ongoing experiment carried on in Red Mountain American Viticulture area near Benton City, Washington, subsurface drip irrigation treatments at 30, 60 and 90 cm depth, and 15, 30 and 60% irrigation were applied to satisfy evapotranspiration demand using pulse and continuous irrigation. These treatments were compared to continuous surface irrigation applied at 100% evapotranspiration demand. Thermal infrared and multispectral images were acquired using unmanned aerial vehicle during the growing season. Obtained results indicated no difference in yield among treatments (p<0.05), however there was statistical difference in leaf temperature comparing surface and subsurface irrigation (p<0.05). Normalized vegetation index obtained from the analysis of multispectral images showed statistical difference among treatments when surface and subsurface irrigation methods were compared. Similar differences in vegetation index values were observed, when irrigation rates were compared. Obtained results show the applicability of aerial thermal infrared and multispectral images to characterize plant responses to different irrigation treatments and use of such information in irrigation scheduling or high-throughput selection of water-use efficient crop varieties in plant breeding.
Ying Ouyang; Gary Feng; Theodor D. Leininger; John Read; Johnie N. Jenkins
2018-01-01
Agricultural ponds are an important alternative source of water for crop irrigation to conserve surface and ground water resources. In recent years more such ponds have been constructed in Mississippi and around the world. There is currently, however, a lack of a tool to simultaneously estimate crop irrigation demand and pond water availability. In this study, a Pond-...
R.T. McNider; C. Handyside; K. Doty; W.L. Ellenburg; J.F. Cruise; J.R. Christy; D. Moss; V. Sharda; G. Hoogenboom; Peter Caldwell
2015-01-01
The present paper discusses a coupled gridded crop modeling and hydrologic modeling system that can examine the benefits of irrigation and costs of irrigation and the coincident impact of the irrigation water withdrawals on surface water hydrology. The system is applied to the Southeastern U.S. The system tools to be discussed include a gridded version (GriDSSAT) of...
Effect of irrigation techniques and strategies on water footprint of growing crops
NASA Astrophysics Data System (ADS)
Chukalla, A. D.; Krol, M. S.; Hoekstra, A. Y. Y.
2014-12-01
Reducing the water footprint (WF) of growing crops, the largest water user and a significant contributor to the WF of many consumer products, plays a significant role in integrated and sustainable water management. The water footprint for growing crop is accounted by relating the crop yield with the corresponding consumptive water use (CWU), which both can be adjusted by measures that affect the crop growth and root-zone soil water balance. This study explored the scope for reducing the water footprint of irrigated crops by experimenting set of field level technical and managerial measures: (i) irrigation technologies (Furrow, sprinkler, drip and sub-surface drip), (ii) irrigation strategies (full and a range of sustained and controlled deficit) and (iii) field management options (zero, organic and synthetic mulching). Ranges of cases were also considered: (a) Arid and semi-arid environment (b) Loam and Sandy-loam soil types and (c) for Potato, Wheat and Maize crops; under (c) wet, normal and dry years. AquaCrop, the water driven crop growth and soil water balance model, offered the opportunity to systematically experiment these measures on water consumption and yield. Further, the green and blue water footprints of growing crop corresponding to each measure were computed by separating the root zone fluxes of the AquaCrop output into the green and blue soil water stocks and their corresponding fluxes. Results showed that in arid environment reduction in irrigation supply, CWU and WF up to 300 mm, 80 mm and 75 m3/tonne respectively can be achieved for Maize by a combination of organic mulching and drip technology with controlled deficit irrigation strategies (10-20-30-40% deficit with reference to the full irrigation requirement). These reductions come with a yield drop of 0.54 tonne/ha. In the same environment under the absence of mulching practice, the sub-surface drip perform better in reducing CWU and WF of irrigated crops followed by drip and furrow irrigation technique. This rank though changes in non-moisture limiting condition (wet year) drip performing better in reducing the WF of growing crops than sub-surface drip. It was observed that with all range of irrigation techniques, strategies and field management practices there is more room in reducing the WF of growing crops in loam than sandy-loam soil.
Memory of irrigation effects on hydroclimate and its modeling challenge
NASA Astrophysics Data System (ADS)
Chen, Fei; Xu, Xiaoyu; Barlage, Michael; Rasmussen, Roy; Shen, Shuanghe; Miao, Shiguang; Zhou, Guangsheng
2018-06-01
Irrigation modifies land-surface water and energy budgets, and also influences weather and climate. However, current earth-system models, used for weather prediction and climate projection, are still in their infancy stage to consider irrigation effects. This study used long-term data collected from two contrasting (irrigated and rainfed) nearby maize-soybean rotation fields, to study the effects of irrigation memory on local hydroclimate. For a 12 year average, irrigation decreases summer surface-air temperature by less than 1 °C and increases surface humidity by 0.52 g kg‑1. The irrigation cooling effect is more pronounced and longer lasting for maize than for soybean. Irrigation reduces maximum, minimum, and averaged temperature over maize by more than 0.5 °C for the first six days after irrigation, but its temperature effect over soybean is mixed and negligible two or three days after irrigation. Irrigation increases near-surface humidity over maize by about 1 g kg‑1 up to ten days and increases surface humidity over soybean (~ 0.8 g kg‑1) with a similar memory. These differing effects of irrigation memory on temperature and humidity are associated with respective changes in the surface sensible and latent heat fluxes for maize and soybean. These findings highlight great need and challenges for earth-system models to realistically simulate how irrigation effects vary with crop species and with crop growth stages, and to capture complex interactions between agricultural management and water-system components (crop transpiration, precipitation, river, reservoirs, lakes, groundwater, etc.) at various spatial and temporal scales.
NASA Astrophysics Data System (ADS)
Nocco, M. A.; Kucharik, C. J.; Kraft, G.
2013-12-01
Regional water scarcity dilemmas between agricultural and aquatic land users pervade the humid northern lake states of Wisconsin, Minnesota, and Michigan, where agricultural irrigation relies on groundwater drawn from shallow aquifers. As these aquifers have strong connectivity to surface waters, irrigation lowers water levels in lakes and wetlands and reduces stream discharges. Irrigation expansion has cultivated a 60-year water scarcity dilemma in The Wisconsin Central Sands, the largest irrigated region in the humid northern lake states, dedicated to potato, maize, and processing vegetable production. Irrigation has depleted Wisconsin Central Sands surface waters, lowering levels in some lakes by over 2 m and drying some coldwater trout streams. Aquatic ecosystems, property values, and recreational uses in some surface waters have been devastated. While the causal link between pumping and surface water stress is established, understanding crop-mediated processes, such as the timing and magnitude of groundwater consumption by evapotranspiration (ET) and groundwater recharge, will be useful in management of groundwater, irrigated cropping systems, and surface water health. Previous modeling and field efforts have compared irrigated crop water use to a natural reference condition on a net annual basis. As a result, we presently understand that for irrigated potatoes and maize, the average annual ET is greater and therefore, the average annual recharge is less than rainfed row crops, grasslands, and both coniferous and deciduous forests. However, we have a limited understanding of the magnitude and timing of ET and recharge from irrigated cropping systems on shorter time scales that proceed with the annual cropping cycle (i.e. planting, full canopy, harvest, residue cover). We seek to understand the spatiotemporal variability of crop water budgets and associated water scarcity in the Wisconsin Central Sands through detailed measurements of drainage (potential recharge) and by inferring ET through difference, modeling, and gas exchange. In April 2013 prior to planting, we installed 10 passive capillary wick lysimeters below the effective rooting zone (z=100 cm) in potato (n=6) and maize (n=4) cropping systems to collect drainage at a 10-minute time-step under cultivation on Isherwood Farms, a sixth-generation family farm in the Wisconsin Central Sands region. Lysimeters were also instrumented to measure soil moisture and temperature at depth (z=10, 20, 40, 80 cm). Farm operators initiated center-pivot irrigation when soil moisture dropped to approximately 50% of plant available water content. Results show that drainage for May-July 2013 was 43 × 53 mm and 48 × 41 mm in irrigated potato and maize cropping systems, respectively, despite 320 mm of precipitation received during the experimental period, which was 15% above average for this region. Soil moisture consistently fluctuated in response to precipitation/irrigation events at the 10 and 20 cm soil depths, but rarely fluctuated in response to precipitation/irrigation events at the 40 and 80 cm soil depths, supporting the low drainage observed during the growing season. Future work will couple these drainage data to ongoing phenological, micrometeorological, and gas exchange observations in order to infer ET and calculate crop water budgets on a seasonal basis.
Quantifying the link between crop production and mined groundwater irrigation in China.
Grogan, Danielle S; Zhang, Fan; Prusevich, Alexander; Lammers, Richard B; Wisser, Dominik; Glidden, Stanley; Li, Changsheng; Frolking, Steve
2015-04-01
In response to increasing demand for food, Chinese agriculture has both expanded and intensified over the past several decades. Irrigation has played a key role in increasing crop production, and groundwater is now an important source of irrigation water. Groundwater abstraction in excess of recharge (which we use here to estimate groundwater mining) has resulted in declining groundwater levels and could eventually restrict groundwater availability. In this study we used a hydrological model, WBMplus, in conjunction with a process based crop growth model, DNDC, to evaluate Chinese agriculture's recent dependence upon mined groundwater, and to quantify mined groundwater-dependent crop production across a domain that includes variation in climate, crop choice, and management practices. This methodology allowed for the direct attribution of crop production to irrigation water from rivers and reservoirs, shallow (renewable) groundwater, and mined groundwater. Simulating 20 years of weather variability and circa year 2000 crop areas, we found that mined groundwater fulfilled 20%-49% of gross irrigation water demand, assuming all demand was met. Mined groundwater accounted for 15%-27% of national total crop production. There was high spatial variability across China in irrigation water demand and crop production derived from mined groundwater. We find that climate variability and mined groundwater demand do not operate independently; rather, years in which irrigation water demand is high due to the relatively hot and dry climate also experience limited surface water supplies and therefore have less surface water with which to meet that high irrigation water demand. Copyright © 2014 Elsevier B.V. All rights reserved.
Khan, Muhammad Usman; Malik, Riffat Naseem; Muhammad, Said
2013-11-01
The current study was designed to investigate the potential human health risks associated with consumption of food crops contaminated with toxic heavy metals. Cadmium (Cd) concentration in surface soils; Cd, lead (Pb) and chromium (Cr) in the irrigation water and food crops were above permissible limits. The accumulation factor (AF) was >1 for manganese (Mn) and Pb in different food crops. The Health Risk Index (HRI) was >1 for Pb in all food crops irrigated with wastewater and tube well water. HRI >1 was also recorded for Cd in all selected vegetables; and for Mn in Spinacia oleracea irrigated with wastewater. All wastewater irrigated samples (soil and food crops) exhibited high relative contamination level as compared to samples irrigated with tube well water. Our results emphasized the need for pretreatment of wastewater and routine monitoring in order to avoid contamination of food crops from the wastewater irrigation system. Copyright © 2013 Elsevier Ltd. All rights reserved.
Soil management and conservation: Irrigation: Methods
USDA-ARS?s Scientific Manuscript database
Irrigation applies water to soil to improve crop production. The three main methods of irrigation are surface, sprinkler and micro. Surface irrigation is used on 85% of the irrigated land in the world. It generally requires lower capital investment because the soil conveys water within the field, ra...
An Assessment of Irrigation Technology Performance in the Southern San Joaquin Valley of California
NASA Astrophysics Data System (ADS)
Vaux, H. J., Jr.; Handley, Dale F.; Giboney, Paul M.
1990-01-01
Seasonal applied water measurements were obtained for 1710 irrigated fields in the southern San Joaquin Valley of California. Most of the fields were planted to one of five major crops: citrus, almonds, grapes, cotton, and small grains. These crops were irrigated with a wide array of irrigation technologies, including drip, sprinkler, furrows with tailwater reuse facilities, conventional furrows, and border irrigation systems. The data were analyzed within an accounting framework to standardize for a variety of climatic and cultural variations. Analyses of the mean depths of applied water by crop and irrigation technology and of the standardized results reveal that drip irrigation systems were associated with the lowest levels of applied water on permanent crops and that the levels of water applied with sprinklers did not differ significantly from those applied with surface systems on either permanent or annual crops.
Uptake and Accumulation of Pharmaceuticals in Lettuce Under Surface and Overhead Irrigations
NASA Astrophysics Data System (ADS)
Bhalsod, G.; Chuang, Y. H.; Jeon, S.; Gui, W.; Li, H.; Guber, A.; Zhang, W.
2015-12-01
Pharmaceuticals and personal care products are being widely detected in wastewater and surface waters. As fresh water becomes scarcer, interests in using reclaimed water for crop irrigation is intensified. Since reclaimed waters often carry trace levels of pharmaceuticals, accumulation of pharmaceuticals in food crops could increase the risk of human exposure. This study aims to investigate uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under contrasting irrigation practices (i.e., overhead and surface irrigations). Lettuce was irrigated with water spiked with 11 commonly used pharmaceuticals (acetaminophen, caffeine, carbamazepine, sulfadiazine, sulfamethoxazole, carbadox, trimethoprim, lincomycin hydrochloride, oxytetracycline hydrochloride, monensin sodium, and tylosin). Weekly sampling of lettuce roots, shoots, and soils were continued for 5 weeks, and the samples were freeze dried, extracted for pharmaceuticals and analyzed by LC-MS/MS. Preliminary results indicate that higher concentrations of pharmaceuticals were found in overhead irrigated lettuce compared to surface irrigated lettuce. For carbamezapine, sulfadiazine, trimethoprim, oxytetracycline, and monensin sodium, their concentrations generally increased in lettuce shoots in the overhead treatment over time. However, acetaminophen was found at higher concentrations in both shoots and roots, indicating that acetaminophen can be easily transported in the plant system. This study provides insight on developing better strategies for using reclaimed water for crop irrigations, while minimizing the potential risks of pharmaceutical contamination of vegetables.
USDA-ARS?s Scientific Manuscript database
Due to recurring agricultural water shortages, many farmers are looking for crops that have both some degree of drought resistance and a higher economic value. Pomegranate has been identified as a crop with potential drought tolerance, and high economic values. To manage limited water effectively, i...
Water and nitrogen requirements of subsurface drip irrigated pomegranate
USDA-ARS?s Scientific Manuscript database
Surface drip irrigation is a well-developed practice for both annual and perennial crops. The use of subsurface drip is a well-established practice in many annual row crops, e.g. tomatoes, strawberries, lettuce. However, the use of subsurface drip on perennial crops has been slow to develop. With th...
Changes in rainfed and irrigated crop yield response to climate in the western US
NASA Astrophysics Data System (ADS)
Li, X.; Troy, T. J.
2018-06-01
As the global population increases and the climate changes, ensuring a secure food supply is increasingly important. One strategy is irrigation, which allows for crops to be grown outside their optimal climate growing regions and which buffers against climate variability. Although irrigation is a positive climate adaptation mechanism for agriculture, it has a potentially negative effect on water resources as it can lead to groundwater depletion and diminished surface water supplies. This study quantifies how crop yields are affected by climate variability and extremes and the impact of irrigation on crop yield increases under various growing-season climate conditions. To do this, we use historical climate data and county-level rainfed and irrigated crop yields for maize, soybean, winter and spring wheat over the US to analyze the relationship between climate, crop yields, and irrigation. We find that there are optimal climates, specific to each crop, where irrigation provides a benefit and other conditions where irrigation proves to have marginal, if any, benefits. Furthermore, the relationship between crop yields and climate has changed over the last decades, with a changing sensitivity in the relationship of soybean and winter wheat yields to certain climate variables, like crop reference evapotranspiration. These two conclusions have important implications for agricultural and water resource system planning, as it implies there are more optimal climate conditions where irrigation is particularly productive and regions where irrigation should be reconsidered as there is not a significant agricultural benefit and the water could be used more productively.
Energy requirements in pressure irrigation systems
NASA Astrophysics Data System (ADS)
Sánchez, R.; Rodríguez-Sinobas, L.; Juana, L.; Laguna, F. V.; Castañón, G.; Gil, M.; Benítez, J.
2012-04-01
Modernization of irrigation schemes, generally understood as transformation of surface irrigation systems into pressure -sprinkler and trickle- irrigation systems, aims at, among others, improving irrigation efficiency and reduction of operation and maintenance efforts made by the irrigators. However, pressure irrigation systems, in contrast, carry a serious energy cost. Energy requirements depend on decisions taken on management strategies during the operation phase, which are conditioned by previous decisions taken on the design project of the different elements which compose the irrigation system. Most of the countries where irrigation activity is significant bear in mind that modernization irrigation must play a key role in the agricultural infrastructure policies. The objective of this study is to characterize and estimate the mean and variation of the energy consumed by common types of irrigation systems and their management possibilities. The work includes all processes involved from the diversion of water into irrigation specific infrastructure to water discharge by the emitters installed on the crop fields. Simulation taking into account all elements comprising the irrigation system has been used to estimate the energy requirements of typical irrigation systems of several crop production systems. It has been applied to extensive and intensive crop systems, such us extensive winter crops, summer crops and olive trees, fruit trees and vineyards and intensive horticulture in greenhouses. The simulation of various types of irrigation systems and management strategies, in the framework imposed by particular cropping systems, would help to develop criteria for improving the energy balance in relation to the irrigation water supply productivity.
Assessing environmental impacts of constructed wetland effluents for vegetable crop irrigation.
Castorina, A; Consoli, S; Barbagallo, S; Branca, F; Farag, A; Licciardello, F; Cirelli, G L
2016-01-01
The objective of this study was to monitor and assess environmental impacts of reclaimed wastewater (RW), used for irrigation of vegetable crops, on soil, crop quality and irrigation equipment. During 2013, effluents of a horizontal sub-surface flow constructed treatment wetland (TW) system, used for tertiary treatment of sanitary wastewater from a small rural municipality located in Eastern Sicily (Italy), were reused by micro-irrigation techniques to irrigate vegetable crops. Monitoring programs, based on in situ and laboratory analyses were performed for assessing possible adverse effects on water-soil-plant systems caused by reclaimed wastewater reuse. In particular, experimental results evidenced that Escherichia coli content found in RW would not present a risk for rotavirus infection following WHO (2006) standards. Irrigated soil was characterized by a certain persistence of microbial contamination and among the studied vegetable crops, lettuce responds better, than zucchini and eggplants, to the irrigation with low quality water, evidencing a bettering of nutraceutical properties and production parameters.
Economic impacts on irrigated agriculture of water conservation programs in drought
NASA Astrophysics Data System (ADS)
Ward, Frank A.
2014-01-01
This study analyzes vulnerability, impacts, and adaptability by irrigation to drought.It accounts for economic incentives affecting choices on irrigation technology, crop mix, and water sources.When surface water supplies fall, farmers increase pumping, even when pumping raises production costs.Conservation program subsidies raise the value of food production but can increase crop water depletions.
NASA Astrophysics Data System (ADS)
Gibson, Justin; Franz, Trenton E.; Wang, Tiejun; Gates, John; Grassini, Patricio; Yang, Haishun; Eisenhauer, Dean
2017-02-01
In many agricultural regions, the human use of water for irrigation is often ignored or poorly represented in land surface models (LSMs) and operational forecasts. Because irrigation increases soil moisture, feedback on the surface energy balance, rainfall recycling, and atmospheric dynamics is not represented and may lead to reduced model skill. In this work, we describe four plausible and relatively simple irrigation routines that can be coupled to the next generation of hyper-resolution LSMs operating at scales of 1 km or less. The irrigation output from the four routines (crop model, precipitation delayed, evapotranspiration replacement, and vadose zone model) is compared against a historical field-scale irrigation database (2008-2014) from a 35 km2 study area under maize production and center pivot irrigation in western Nebraska (USA). We find that the most yield-conservative irrigation routine (crop model) produces seasonal totals of irrigation that compare well against the observed irrigation amounts across a range of wet and dry years but with a low bias of 80 mm yr-1. The most aggressive irrigation saving routine (vadose zone model) indicates a potential irrigation savings of 120 mm yr-1 and yield losses of less than 3 % against the crop model benchmark and historical averages. The results of the various irrigation routines and associated yield penalties will be valuable for future consideration by local water managers to be informed about the potential value of irrigation saving technologies and irrigation practices. Moreover, the routines offer the hyper-resolution LSM community a range of irrigation routines to better constrain irrigation decision-making at critical temporal (daily) and spatial scales (< 1 km).
NASA Astrophysics Data System (ADS)
Feng, G.; Gao, F.; Ouyang, Y.
2017-12-01
The Mississippi River is North America's largest river and the second largest watershed in the world. It flows over 3,700 km through America's heartland to the Gulf of Mexico. Over 3 million hectares in the Lower Mississippi River Basin represent irrigated cropland and 90 percent of those lands currently rely on the groundwater supply. The primary crops grown in this region are soybean, corn, cotton, and rice. Increased water withdrawals for irrigating those crops and stagnant recharging jeopardize the long-term availability of the aquifer and place irrigation agriculture in the region on an unsustainable path. The objectives of this study were to: 1) analyze the current groundwater level in the Lower Mississippi River Basin based on the water table depth observed by Yazoo Mississippi Delta Joint Water Management District from 2000 and 2016; 2) determine trends of change in groundwater level under conventional and groundwater saving irrigation management practices (ET or soil moisture based full irrigation scheduling using all groundwater or different percentages of ground and surface water). The coupled SWAT and MODFLOW model was applied to investigate the trends. Observed results showed that the groundwater level has declined from 33 to 26 m at an annual decrease rate of 0.4 m in the past 17 years. Simulated results revealed that the groundwater storage was decreased by 26 cm/month due to irrigation in crop season. It is promising that the groundwater storage was increased by 23 cm/month, sometimes even 60 cm/month in crop off-growing season because of recharge from rainfall. Our results suggest that alternative ET or soil moisture based groundwater saving irrigation scheduling with conjunctive use of surface water is a sustainable practice for irrigated agriculture in in the Lower Mississippi River Basin.
NASA Astrophysics Data System (ADS)
Okada, M.; Sakurai, G.; Iizumi, T.; Yokozawa, M.
2012-12-01
Agricultural production utilizes regional resources (e.g. river water and ground water) as well as local resources (e.g. temperature, rainfall, solar energy). Future climate changes and increasing demand due to population increases and economic developments would intensively affect the availability of water resources for agricultural production. While many studies assessed the impacts of climate change on agriculture, there are few studies that dynamically account for changes in water resources and crop production. This study proposes an integrated model for assessing both crop productivity and agricultural water resources at a large scale. Also, the irrigation management to subseasonal variability in weather and crop response varies for each region and each crop. To deal with such variations, we used the Markov Chain Monte Carlo technique to quantify regional-specific parameters associated with crop growth and irrigation water estimations. We coupled a large-scale crop model (Sakurai et al. 2012), with a global water resources model, H08 (Hanasaki et al. 2008). The integrated model was consisting of five sub-models for the following processes: land surface, crop growth, river routing, reservoir operation, and anthropogenic water withdrawal. The land surface sub-model was based on a watershed hydrology model, SWAT (Neitsch et al. 2009). Surface and subsurface runoffs simulated by the land surface sub-model were input to the river routing sub-model of the H08 model. A part of regional water resources available for agriculture, simulated by the H08 model, was input as irrigation water to the land surface sub-model. The timing and amount of irrigation water was simulated at a daily step. The integrated model reproduced the observed streamflow in an individual watershed. Additionally, the model accurately reproduced the trends and interannual variations of crop yields. To demonstrate the usefulness of the integrated model, we compared two types of impact assessment of climate change on crop productivity in a watershed. The first was carried out by the large-scale crop model alone. The second was carried out by the integrated model of the large-scale crop model and the H08 model. The former projected that changes in temperature and precipitation due to future climate change would give rise to increasing the water stress in crops. Nevertheless, the latter projected that the increasing amount of agricultural water resources in the watershed would supply sufficient amount of water for irrigation, consequently reduce the water stress. The integrated model demonstrated the importance of taking into account the water circulation in watershed when predicting the regional crop production.
Irrigation Trials for ET Estimation and Water Management in California Specialty Crops
NASA Astrophysics Data System (ADS)
Johnson, L.; Cahn, M.; Martin, F.; Lund, C.; Melton, F. S.
2012-12-01
Accurate estimation of crop evapotranspiration (ETc) can support efficient irrigation water management, which in turn brings benefits including surface water conservation, mitigation of groundwater depletion/degradation, energy savings, and crop quality assurance. Past research in California has revealed strong relationships between canopy fractional cover (Fc) and ETc of certain specialty crops, while additional research has shown the potential of monitoring Fc by satellite remote sensing. California's Central Coast is the leading region of cool season vegetable production in the U.S. Monterey County alone produces more than 80,000 ha of lettuce and broccoli (about half of U.S. production), valued at $1.5 billion in 2009. Under this study, we are conducting ongoing irrigation trials on these crops at the USDA Agricultural Research Station (Salinas) to compare irrigation scheduling via plant-based ETc approaches, by way of Fc, with current industry standard-practice. The following two monitoring approaches are being evaluated - 1) a remote sensing model employed by NASA's prototype Satellite Irrigation Management System, and 2) an online irrigation scheduling tool, CropManage, recently developed by U.C. Cooperative Extension. Both approaches utilize daily grass-reference ETo data as provided by the California Irrigation Management Irrigation System (CIMIS). A sensor network is deployed to monitor applied irrigation, volumetric soil water content, soil water potential, deep drainage, and standard meteorologic variables in order to derive ETc by a water balance approach. Evaluations of crop yield and crop quality are performed by the research team and by commercial growers. Initial results to-date indicate that applied water reductions based on Fc measurements are possible with little-to-no impact on yield of crisphead lettuce (Lactuca sativa). Additional results for both lettuce and broccoli trials, conducted during summer-fall 2012, are presented with respect to nutrient management and crop viability.
NASA Astrophysics Data System (ADS)
Melton, F. S.; Johnson, L.; Post, K. M.; Guzman, A.; Zaragoza, I.; Spellenberg, R.; Rosevelt, C.; Michaelis, A.; Nemani, R. R.; Cahn, M.; Frame, K.; Temesgen, B.; Eching, S.
2016-12-01
Satellite mapping of evapotranspiration (ET) from irrigated agricultural lands can provide agricultural producers and water managers with information that can be used to optimize agricultural water use, especially in regions with limited water supplies. The timely delivery of information on agricultural crop water requirements has the potential to make irrigation scheduling more practical, convenient, and accurate. We present a system for irrigation scheduling and management support in California and describe lessons learned from the development and implementation of the system. The Satellite Irrigation Management Support (SIMS) framework integrates satellite data with information from agricultural weather networks to map crop canopy development, basal crop coefficients (Kcb), and basal crop evapotranspiration (ETcb) at the scale of individual fields. Information is distributed to agricultural producers and water managers via a web-based irrigation management decision support system and web data services. SIMS also provides an application programming interface (API) that facilitates integration with other irrigation decision support tools, estimation of total crop evapotranspiration (ETc) and calculation of on-farm water use efficiency metrics. Accuracy assessments conducted in commercial fields for more than a dozen crop types to date have shown that SIMS seasonal ETcb estimates are within 10% mean absolute error (MAE) for well-watered crops and within 15% across all crop types studied, and closely track daily ETc and running totals of ETc measured in each field. Use of a soil water balance model to correct for soil evaporation and crop water stress reduces this error to less than 8% MAE across all crop types studied to date relative to field measurements of ETc. Results from irrigation trials conducted by the project for four vegetable crops have also demonstrated the potential for use of ET-based irrigation management strategies to reduce total applied water by 20-40% relative to grower standard practices while maintaining crop yields and quality.
Agricultural irrigated land-use inventory for Osceola County, Florida, October 2013-April 2014
Marella, Richard L.; Dixon, Joann F.
2014-01-01
A detailed inventory of irrigated crop acreage is not available at the level of resolution needed to increase the accuracy of current water-use estimates or to project future water demands in many Florida counties. This report provides a detailed digital map and summary of irrigated areas within Osceola County for the agricultural growing period October 2013–April 2014. The irrigated areas were first delineated using land-use data and satellite imagery and then field verified between February and April 2014. Selected attribute data were collected for the irrigated areas, including crop type, primary water source, and type of irrigation system. Results indicate that an estimated 27,450 acres were irrigated during the study period. This includes 4,370 acres of vegetables, 10,970 acres of orchard crops, 1,620 acres of field crops, and 10,490 acres of ornamentals and grasses. Specifically, irrigated acreage included citrus (10,860 acres), sod (5,640 acres), pasture (4,580 acres), and potatoes (3,320 acres). Overall, groundwater was used to irrigate 18,350 acres (67 percent of the total acreage), and surface water was used to irrigate the remaining 9,100 acres (33 percent). Microirrigation systems accounted for 45 percent of the total acreage irrigated, flood systems 30 percent, and sprinkler systems the remaining 25 percent. An accurate, detailed, spatially referenced, and field-verified inventory of irrigated crop acreage can be used to assist resource managers making current and future county-level water-use estimates in Osceola County.
NASA Astrophysics Data System (ADS)
Ahn, S.; Sheng, Z.; Abudu, S.
2017-12-01
Hydrologic cycle of agricultural area has been changing due to the impacts of climate and land use changes (crop coverage changes) in an arid region of Rincon Valley, New Mexico. This study is to evaluate the impacts of weather condition and crop coverage change on hydrologic behavior of agricultural area in Rincon Valley (2,466km2) for agricultural watershed management using a watershed-scale hydrologic model, SWAT (Soil and Water Assessment Tool). The SWAT model was developed to incorporate irrigation of different crops using auto irrigation function. For the weather condition and crop coverage change evaluation, three spatial crop coverages including a normal (2008), wet (2009), and dry (2011) years were prepared using USDA crop data layer (CDL) for fourteen different crops. The SWAT model was calibrated for the period of 2001-2003 and validated for the period of 2004-2006 using daily-observed streamflow data. Scenario analysis was performed for wet and dry years based on the unique combinations of crop coverages and releases from Caballo Reservoir. The SWAT model simulated the present vertical water budget and horizontal water transfer considering irrigation practices in the Rincon Valley. Simulation results indicated the temporal and spatial variability for irrigation and non-irrigation seasons of hydrologic cycle in agricultural area in terms of surface runoff, evapotranspiration, infiltration, percolation, baseflow, soil moisture, and groundwater recharge. The water supply of the dry year could not fully cover whole irrigation period due to dry weather conditions, resulting in reduction of crop acreage. For extreme weather conditions, the temporal variation of water budget became robust, which requires careful irrigation management of the agricultural area. The results could provide guidelines for farmers to decide crop patterns in response to different weather conditions and water availability.
Groundwater Ecosystems Vary with Land Use across a Mixed Agricultural Landscape.
Korbel, K L; Hancock, P J; Serov, P; Lim, R P; Hose, G C
2013-01-01
Changes in surface land use may threaten groundwater quality and ecosystem integrity, particularly in shallow aquifers where links between groundwater and surface activities are most intimate. In this study we examine the response of groundwater ecosystem to agricultural land uses in the shallow alluvial aquifer of the Gwydir River valley, New South Wales, Australia. We compared groundwater quality and microbial and stygofauna assemblages among sites under irrigated cropping, non-irrigated cropping and grazing land uses. Stygofauna abundance and richness was greatest at irrigated sites, with the composition of the assemblage suggestive of disturbance. Microbial assemblages and water quality also varied with land use. Our study demonstrates significant differences in the composition of groundwater ecosystems in areas with different surface land use, and highlights the utility of groundwater biota for biomonitoring, particularly in agricultural landscapes. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
NASA Astrophysics Data System (ADS)
Chinnayakanahalli, K.; Adam, J. C.; Stockle, C.; Nelson, R.; Brady, M.; Rajagopalan, K.; Barber, M. E.; Dinesh, S.; Malek, K.; Yorgey, G.; Kruger, C.; Marsh, T.; Yoder, J.
2011-12-01
For better management and decision making in the face of climate change, earth system models must explicitly account for natural resource and agricultural management activities. Including crop system, water management, and economic models into an earth system modeling framework can help in answering questions related to the impacts of climate change on irrigation water and crop productivity, how agricultural producers can adapt to anticipated climate change, and how agricultural practices can mitigate climate change. Herein we describe the coupling of the Variability Infiltration Capacity (VIC) land surface model, which solves the water and energy balances of the hydrologic cycle at regional scales, with a crop-growth model, CropSyst. This new model, VIC-CropSyst, is the land surface model that will be used in a new regional-scale model development project focused on the Pacific Northwest, termed BioEarth. Here we describe the VIC-CropSyst coupling process and its application over the Columbia River basin (CRB) using agricultural-specific land cover information. The Washington State Department of Agriculture (WSDA) and U. S. Department of Agriculture (USDA) cropland data layers were used to identify agricultural land use patterns, in which both irrigated and dry land crops were simulated. The VIC-CropSyst model was applied over the CRB for the historical period of 1976 - 2006 to establish a baseline for surface water availability, irrigation demand, and crop production. The model was then applied under future (2030s) climate change scenarios derived from statistically-downscaled Global Circulation Models output under two emission scenarios (A1B and B1). Differences between simulated future and historical irrigation demand, irrigation water availability, and crop production were used in an economics model to identify the most economically-viable future cropping pattern. The economics model was run under varying scenarios of regional growth, trade, water pricing, and water capacity providing a spectrum of possible future cropping patterns. The resulting cropping patterns were then used in VIC-CropSyst to quantify the impacts of climate change, economic, and water management scenarios on crop production, and water resources availability. This modeling framework provides opportunities to study the interactions between human activities and complex natural processes and is a valuable tool for inclusion in an earth system model with the goal of informing land use and water management.
Recent decline in crop water productivity in the United States: a call to grow "more crop per drop"
NASA Astrophysics Data System (ADS)
Marshall, M. T.; Tu, K. P.; Thenkabail, P.; Brown, J. F.
2016-12-01
Irrigation for agriculture accounts for approximately 80 to 90% of U.S. consumptive water use. Recent declines in freshwater supply for irrigated agriculture in the western U.S. is particularly alarming, because climate change, water withdrawals from growing and competing sectors, and water pollution, are projected to put further strain on this vital sector. Innovative water management strategies are being proposed to combat this eminent water crisis and include: developing water markets, improving crop water productivity (CWP: "more crop per drop"), and coordinating the use of surface and groundwater supplies. The increase in CWP through crop type or variety selection is particularly lucrative, because it aims to increase the marketable yield of a crop, while reducing the cost of consumptive water use. Here we estimated CWP from 2000-2015 for the Contiguous United States over the primary growing season (mid May - late October) using a recently developed and validated light-use efficiency model for estimating crop yield and the transpiration component of the Priestley-Taylor Jet Propulsion Laboratory evapotranspiration model. The models were parameterized with daily DAYMET 1 km meteorological and 7-day EROS Moderate Resolution Imaging Spectroradiometer 250 m vegetation data. An analysis will be performed on CWP and its components to characterize the magnitude, direction, and persistence of trends. CWP estimates and trends will be overlaid with the U.S. Department of Agriculture's Cropland Data Layer to rank major crops by water use versus marketable yield and to characterize intervention hotspots, respectively. County-level data on surface and ground water withdrawals for irrigated agriculture available through the U.S. Geological Survey will be used to further scrutinize emerging patterns. It is anticipated that over much of the irrigated areas of the western U.S. that persistent and decreasing trends in CWP for major water users (e.g. alfalfa) due to temperature-driven increases in atmospheric moisture demand or potential evapotranspiration will correspond to a decrease (increase) in surface (ground) water use for irrigation.
NASA Astrophysics Data System (ADS)
Mantino, Alberto; Marchina, Chiara; Bonari, Enrico; Fabbrizzi, Alessandro; Rossetto, Rudy
2017-04-01
During the last decades in coastal areas of the Mediterranean basin, human growth posed severe stresses on freshwater resources due to increasing demand by agricultural, industrial and civil activities, in particular on groundwater. This in turn led to worsening of water quality, loss/reduction of wetlands, up to soil salinization and abandonment of agricultural areas. Within the EU LIFE REWAT project a number of demonstration measures will take place in the lower Cornia valley (Livorno, Italy), both structural (pilot) and non-structural (education, dissemination and capacity building), aiming at achieving sustainable and participated water management. In particular, the five demonstration actions are related to: (1) set up of a managed aquifer recharge facility, (2) restoration of a Cornia river reach, (3) water saving in the civil water supply sector, (4) water saving in agriculture, (5) reuse of treated wastewater for irrigation purposes. Thus, the REWAT project general objective is to develop a new model of governance for sustainable development of the lower Cornia valley based on the water asset at its core. As per water use in agriculture, the lower Cornia valley is well known for the horticultural production. In this regard, globe artichoke (Cynara cardunculus L. var. scolymus L. (Fiori)) crops, a perennial cool-season vegetable, cover a surface of about 600 ha. In order to increase stability and productivity of the crop, about 2000 - 4000 m3 ha-1 yr-1 of irrigation water is required. Recent studies demonstrated that yield of different crops increases using Sub-surface Drip-Irrigation (SDI) system under high frequency irrigation management enhancing water use efficiency. In the SDI systems, the irrigation water is delivered to the plant root zone, below the soil surface by buried plastic tubes containing embedded emitters located at regular spacing. Within the LIFE REWAT, the specific objectives of the pilot on irrigation efficiency is to (i) demonstrate the suitability of SDI for globe artichoke cultivation, reducing the water consumption, while maintaining (or even increasing) crop production and (ii) assess the crop water use efficiency respect to surface drip-irrigation. The field test is located in Venturina (Italy) and it covers a surface of 4 ha. The soil is characterized by sandy-loam texture, 1.72% of organic matter at 7.81 pH. Groundwater is the main source of supply for irrigation. By the chemical point of view, a monitoring campaign in spring 2016 showed a neutral pH of 7.2, electrical conductivity of 1363 μS/cm, 373 and 243 mg/l of total sulphate and carbonate, respectively, thus demonstrating the suitability of groundwater for SDI application. The SDI system was implemented at the beginning of September 2016. The sub-surface buried pipelines, were placed at 0.25 m depth, with emitters spaced 0.5 m. The distance between pipelines was 1.5 m, according to globe artichoke layout (1.5 m between rows, 1 m in-row spacing). Surface-buried tubes were placed in an area about 0.75 ha wide for the comparison with SDI. Artichoke var. Terom were transplanted after the SDI operation test. In the next 3 years, both crop productivity and water use will be assessed. Results will be presented and discussed with the whole farmer's community. Acknowledgement This paper is presented within the framework of the project LIFE REWAT, which has received funding from the LIFE Programme of the European Union Grant Agreement LIFE14 ENV/IT/001290.
Irrigation management with remote sensing. [Navajo Indian Irrigation Project
NASA Technical Reports Server (NTRS)
Harlan, C.; Heilman, J. L.; Moore, D.; Myers, V. (Principal Investigator)
1982-01-01
Two visible/near IR hand held radiometers and a hand held thermoradiometer were used along with soil moisture and lysimetric measurements in a study of soil moisture distribution in afalfa fields on the Navajo Indian Irrigation Project near farmington, New Mexico. Radiances from irrigated plots were measured and converted to reflectances. Surface soil water contents (o cm to 4 cm) were determined gravimetrically on samples collected at the same time as the spectral measurements. The relationship between the spectral measurements and the crop coefficient were evaluated to demonstrate potential for using spectral measurement to estimate crop coefficient.
7 CFR 760.809 - Eligible damaging conditions.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF... has been an eligible loss of surface irrigation water due to drought and such loss of surface irrigation water impacts eligible crop acreage, FSA may approve assistance to the extent permitted by section...
7 CFR 760.809 - Eligible damaging conditions.
Code of Federal Regulations, 2010 CFR
2010-01-01
... Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF... has been an eligible loss of surface irrigation water due to drought and such loss of surface irrigation water impacts eligible crop acreage, FSA may approve assistance to the extent permitted by section...
Coastal surface water suitability analysis for irrigation in Bangladesh
NASA Astrophysics Data System (ADS)
Mahtab, Mohammad Hossain; Zahid, Anwar
2018-03-01
Water with adequate quality and quantity is very important for irrigation to ensure the crop yields. Salinity is common problem in the coastal waters in Bangladesh. The intensity of salinity in the coastal zone in Bangladesh is not same. It fluctuates over the year. Sodium is another hazard which may hamper permeability and ultimately affects the fertility. It can reduce the crop yields. Although surface water is available in the coastal zone of Bangladesh, but its quality for irrigation needs to be monitored over the year. This paper will investigate the overall quality of coastal surface waters. Thirty-three water samples from different rivers were collected both in wet period (October-December) and in dry period (February-April). Different physical and chemical parameters are considered for investigation of the adequacy of water with respect to international irrigation water quality standards and Bangladesh standards. A comparison between the dry and wet period coastal surface water quality in Bangladesh will also be drawn here. The analysis shows that coastal surface water in Bangladesh is overall suitable for irrigation during wet period, while it needs treatment (which will increase the irrigation cost) for using for irrigation during dry period. Adaptation to this situation can improve the scenario. An integrated plan should be taken to increase the water storing capacity in the coastal area to harvest water during wet period.
Krupnik, Timothy J; Schulthess, Urs; Ahmed, Zia Uddin; McDonald, Andrew J
2017-01-01
Changing dietary preferences and population growth in South Asia have resulted in increasing demand for wheat and maize, along side high and sustained demand for rice. In the highly productive northwestern Indo-Gangetic Plains of South Asia, farmers utilize groundwater irrigation to assure that at least two of these crops are sequenced on the same field within the same year. Such double cropping has had a significant and positive influence on regional agricultural productivity. But in the risk-prone and food insecure lower Eastern Indo-Gangetic Plains (EIGP), cropping is less intensive. During the dryer winter months, arable land is frequently fallowed or devoted to lower yielding rainfed legumes. Seeing opportunity to boost cereals production, particularly for rice, donors and land use policy makers have consequently reprioritized agricultural development investments in this impoverished region. Tapping groundwater for irrigation and intensified double cropping, however, is unlikely to be economically viable or environmentally sound in the EIGP. Constraints include saline shallow water tables and the prohibitively high installation and energetic extraction costs from deeper freshwater aquifers. The network of largely underutilized rivers and natural canals in the EIGP could conversely be tapped to provide less energetically and economically costly surface water irrigation (SWI). This approach is now championed by the Government of Bangladesh, which has requested USD 500 million from donors to implement land and water use policies to facilitate SWI and double cropping. Precise geospatial assessment of where freshwater flows are most prominent, or where viable fallow or low production intensity cropland is most common, however remains lacking. In response, we used remotely sensed data to identify agricultural land, detect the temporal availability of freshwater in rivers and canals, and assess crop production intensity over a three-year study period in a 33,750 km 2 case study area in southwestern Bangladesh. We combined these data with georeferenced and temporally explicitly soil and water salinity information, in addition to relative elevation classifications, in order to examine the extent of winter fallows and low productivity rainfed cropland that could be irrigated by small-scale surface water pumps. Applying observations of irrigated crop sowing dates and yields from 510 wheat, 550 maize, and 553 rice farmers, we also modeled crop intensification production scenarios within the case study area. We conservatively estimate that at least 20,800 and 103,000 ha of fallow and rainfed cropland, respectively, could be brought into intensified double cropping using SWI. Scenario analysis indicates that if 25%-75% of the fallow or low-intensity land were converted to irrigated maize, national aggregate production could increase by 10-14% or 29-42%, respectively. Conversion to wheat would conversely boost national production by 9-10% or 26-31%. Irrigated rice is however unlikely to contribute >3%. In aggregate, these actions could generate between USD 36-108 million of revenue annually among farmers. Intensification therefore has important land use policy and food and income security implications, helping to rationalizei SWI investments. Crop choice, water resource allocation, and water governance will however remain crucial considerations for irrigation planners.
Irrigation management strategies to improve Water Use Efficiency of potatoes crop in Central Tunisia
NASA Astrophysics Data System (ADS)
Ghazouani, Hiba; Provenzano, Giuseppe; Rallo, Giovanni; Mguidiche, Amel; Douh, Boutheina; Boujelben, Abdelhamid
2015-04-01
In Tunisia, the expansion of irrigated area and the semiarid climate make it compulsory to adopt strategies of water management to increase water use efficiency. Subsurface drip irrigation (SDI), providing the application of high frequency small irrigation volumes below the soil surface have been increasingly used to enhance irrigation efficiency. At the same time, deficit irrigation (DI) has shown successful results with a large number of crop in various countries. However, for some crops like potatoes, DI is difficult to manage due to the rapid effect of water stress on tuber yield. Irrigation frequency is a key factor to schedule subsurface drip irrigation because, even maintaining the total seasonal volume, soil wetting patterns can result different during the growth period, with consequence on crop yield. Despite the need to enhance water use efficiency, only a few studies related to deficit irrigation of horticultural crops have been made in Tunisia. Objective of the paper was to assess the effects of different on-farm irrigation strategies on water use efficiency of potatoes crop irrigated with subsurface drip irrigation in a semiarid area of central Tunisia. After validation, Hydrus-2D model was used to simulate soil water status in the root zone, to evaluate actual crop evapotranspiration and then to estimate indirectly water use efficiency (IWUE), defined as the ratio between crop yield and total amount of water supplied with irrigation. Field experiments, were carried out in Central Tunisia (10° 33' 47.0" E, 35° 58' 8.1° N, 19 m a.s.l) on a potatoes crop planted in a sandy loam soil, during the growing season 2014, from January 15 (plantation of tubers) to May 6 (harvesting). Soil water status was monitored in two plots (T1 and T2) maintained under the same management, but different irrigation volumes, provided by a SDI system. In particular, irrigation was scheduled according to the average water content measured in the root zone, with a total of 8 watering, with timing ranging between one and three hours in T1, and between about half-an-hour and one-hour and a-half, in T2. The validity of Hydrus-2D model was initially assessed based on the comparison between measured and estimated soil water content at different distances from the emitter (RMSE values were not higher than 0.036). Then, model simulations allowed to verify that it is possible to enhance irrigation water use efficiency by increasing the frequency of irrigation even maintaining limited water deficit conditions during the full development stage subsequent the crop tuberization. Experimental results, joined to model simulations can therefore provide useful guidelines for a more sustainable use of irrigation water in countries characterised by semi-arid environments and limited availability of water resources.
Droplet kinetic energy of moving spray-plate center-pivot irrigation sprinklers
USDA-ARS?s Scientific Manuscript database
The kinetic energy of discrete water drops impacting a bare soil surface generally leads to a drastic reduction in water infiltration rate due to formation of a seal on the soil surface. Under center-pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy development ...
NASA Astrophysics Data System (ADS)
Kumari, S.; Sharma, P.; Srivastava, A.; Rastogi, D.; Sehgal, V. K.; Dhakar, R.; Roy, S. B.
2017-12-01
Vegetation dynamics and surface meteorology are tightly coupled through the exchange of momentum, moisture and heat between the land surface and the atmosphere. In this study, we use a recently developed coupled atmosphere-crop growth dynamics model to study these exchanges and their effects in a spring wheat cropland in northern India. In particular, we investigate the role of irrigation in controlling crop growth rates, surface meteorology, and sensible and latent heat fluxes. The model is developed by implementing a crop growth module based on the Simple and Universal Crop growth Simulator (SUCROS) model in the Weather Research Forecasting (WRF) mesoscale atmospheric model. The crop module calculates photosynthesis rates, carbon assimilation, and biomass partitioning as a function of environmental factors and crop development stage. The leaf area index (LAI) and root depth calculated by the crop module is then fed to the Noah-MP land module of WRF to calculate land-atmosphere fluxes. The crop model is calibrated using data from an experimental spring wheat crop site in the Indian Agriculture Research Institute. The coupled model is capable of simulating the observed spring wheat phenology. Irrigation is simulated by changing the soil moisture levels from 50% - 100% of field capacity. Results show that the yield first increases with increasing soil moisture and then starts decreasing as we further increase the soil moisture. Yield attains its maximum value with soil moisture at the level of 60% water of FC. At this level, high LAI values lead to a decrease in the Bowen Ratio because more energy is transferred to the atmosphere as latent heat rather than sensible heat resulting in a cooling effect on near-surface air temperatures. Apart from improving simulation of land-atmosphere interactions, this coupled modeling approach can form the basis for the seamless crop yield and seasonal scale weather outlook prediction system.
Brown, Jesslyn; Pervez, Md Shahriar
2014-01-01
Over 22 million hectares (ha) of U.S. croplands are irrigated. Irrigation is an intensified agricultural land use that increases crop yields and the practice affects water and energy cycles at, above, and below the land surface. Until recently, there has been a scarcity of geospatially detailed information about irrigation that is comprehensive, consistent, and timely to support studies tying agricultural land use change to aquifer water use and other factors. This study shows evidence for a recent overall net expansion of 522 thousand ha across the U.S. (2.33%) and 519 thousand ha (8.7%) in irrigated cropped area across the High Plains Aquifer (HPA) from 2002 to 2007. In fact, over 97% of the net national expansion in irrigated agriculture overlays the HPA. We employed a modeling approach implemented at two time intervals (2002 and 2007) for mapping irrigated agriculture across the conterminous U.S. (CONUS). We utilized U.S. Department of Agriculture (USDA) county statistics, satellite imagery, and a national land cover map in the model. The model output, called the Moderate Resolution Imaging Spectroradiometer (MODIS) Irrigated Agriculture Dataset for the U.S. (MIrAD-US), was then used to reveal relatively detailed spatial patterns of irrigation change across the nation and the HPA. Causes for the irrigation increase in the HPA are complex, but factors include crop commodity price increases, the corn ethanol industry, and government policies related to water use. Impacts of more irrigation may include shifts in local and regional climate, further groundwater depletion, and increasing crop yields and farm income.
USDA-ARS?s Scientific Manuscript database
The kinetic energy of discrete drops impacting a bare soil surface is generally observed to lead to a drastic reduction in water infiltration rate due to soil surface seal formation. Under center pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy development can...
Balkhair, Khaled S.
2015-01-01
Increasing lack of potable water in arid countries leads to the use of treated wastewater for crop production. However, the use of inappropriate irrigation practices could result in a serious contamination risk to plants, soils, and groundwater with sewage water. This research was initiated in view to the increasing danger of vegetable crops and groundwater contamination with pathogenic bacteria due to wastewater land application. The research was designed to study: (1) the effect of treated wastewater irrigation on the yield and microbial contamination of the radish plant under field conditions; (2) contamination of the agricultural soil profile with fecal coliform bacteria. Effluent from a domestic wastewater treatment plant (100%) in Jeddah city, Saudi Arabia, was diluted to 80% and 40% with the groundwater of the experimental site constituting three different water qualities plus groundwater as control. Radish plant was grown in two consecutive seasons under two drip irrigation systems and four irrigation water qualities. Upon harvesting, plant weight per ha, total bacterial, fecal coliform, fecal streptococci were detected per 100 g of dry matter and compared with the control. The soil profile was also sampled at an equal distance of 3 cm from soil surface for fecal coliform detection. The results indicated that the yield increased significantly under the subsurface irrigation system and the control water quality compared to surface irrigation system and other water qualities. There was a considerable drop in the count of all bacteria species under the subsurface irrigation system compared to surface irrigation. The bacterial count/g of the plant shoot system increased as the percentage of wastewater in the irrigation water increased. Most of the fecal coliform bacteria were deposited in the first few centimeters below the column inlet and the profile exponentially decreased with increasing depth. PMID:26858571
Mapping and monitoring of crop intensity, calendar and irrigation using multi-temporal MODIS data
NASA Astrophysics Data System (ADS)
Xiao, X.; Boes, S.; Mulukutla, G.; Proussevitch, A.; Routhier, M.
2005-12-01
Agriculture is the most extensive land use and water use on the Earth. Because of the diverse range of natural environments and human needs, agriculture is also the most complicated land use and water use system, which poses an enormous challenge to the scientific community, the public and decision-makers. Updated and geo-referenced information on crop intensity (number of crops per year), calendar (planting date, harvesting date) and irrigation is critically needed to better understand the impacts of agriculture on biogeochemical cycles (e.g., carbon, nitrogen, trace gases), water and climate dynamics. Here we present an effort to develop a novel approach for mapping and monitoring crop intensity, calendar and irrigation, using multi-temporal Moderate Resolution Imaging Spectroradiometer (MODIS) image data. Our algorithm employed three vegetation indices that are sensitive to the seasonal dynamics of leaf area index, light absorption by leaf chlorophyll and land surface water content. Our objective is to generate geospatial databases of crop intensity, calendar and irrigation at 500-m spatial resolution and at 8-day temporal resolution. In this presentation, we report a preliminary geospatial dataset of paddy rice crop intensity, calendar and irrigation in Asia, which is developed from the 8-day composite images of MODIS in 2002. The resultant dataset could be used in many applications, including hydrological and climate modeling.
NASA Astrophysics Data System (ADS)
Ren, D.; Huang, G., Sr.; Xu, X.; Huang, Q., Sr.; Xiong, Y.
2016-12-01
Soil salinity analysis on a regional scale is of great significance for protecting agriculture production and maintaining eco-environmental health in arid and semi-arid irrigated areas. In this study, the Hetao Irrigation District (Hetao) in Inner Mongolia Autonomous Region, with suffering long-term soil salinization problems, was selected as the case study area. Field sampling experiments and investigations related to soil salt contents, crop growth and yields were carried out across the whole area, during April to August in 2015. Soil salinity characteristics in space and time were systematically analyzed for Hetao as well as the corresponding impacts on crops. Remotely sensed map of soil salinity distribution for surface soil was also derived based on the Landsat OLI data with a 30 m resolution. The results elaborated the temporal and spatial dynamics of soil salinity and the relationships with irrigation, groundwater depth and crop water consumption in Hetao. In addition, the strong spatial variability of salinization was clearly presented by the remotely sensed map of soil salinity. Further, the relationship between soil salinity and crop growth was analyzed, and then the impact degrees of soil salinization on cropping pattern, leaf area index, plant height and crop yield were preliminarily revealed. Overall, this study can provide very useful information for salinization control and guide the future agricultural production and soil-water management for the arid irrigation districts analogous to Hetao.
More crop per drop - Increasing input efficiency in sprinkler irrigated potatoes.
NASA Astrophysics Data System (ADS)
Kostka, Stan; Fang, Lisa; Ren, Haiqin; Glucksman, Robert; Gadd, Nick
2014-05-01
Water scarcity, climate change, and population growth are significant global challenges for producing sufficient food, fiber, and fuel in the 21st century. Feeding an increasingly hungry world necessitates innovative strategies and technologies to maximize crop production outputs while simultaneously increasing crop water productivity. In the 20th century, major advances in precision irrigation enabled producers to increase productivity while more efficiently applying water to crops. While pressurized irrigation systems can deliver water effectively to the soil surface, the efficiency of rootzone delivery may be compromised by intrinsic heterogeneities in soil wetting characteristics related to organic matter, biofilms, and hydrophobic coatings on soil particles and aggregates. Efficiently delivering applied irrigation water throughout the soil matrix is critical to increasing crop productivity. We propose that management of soil water access by surfactants is a viable management option to maintain or increase yields under deficit irrigation. Potato yield and tuber quality under sprinkler irrigation were evaluated under standard production practices or with the inclusion of an aqueous nonionic surfactant formulation (10 wt% alkoxylated polyols and 7% glucoethers) applied at 10L ha-1 between emergence and tuberization. Crop responses from multi-year evaluations conducted on irrigated potatoes in Idaho (USA) were compared to multi-year on farm grower evaluations in Australia and China. Surfactant treatment resulted in statistically significant increases in yield (+5%) and US No. 1 grades (+8%) while reducing culls (-10%) in trials conducted in Idaho, USA. Similar responses were observed in commercial grower evaluations conducted in Australia (+8% total yield, +18% mean tuber weight) and in China in 2011 (+8% total yield and +18% premium, -12% culls). Under diverse production conditions, a single application of the surfactant formulation improved crop water productivity in water stressed environments. Results from these trials support our hypothesis that surfactants may be a viable management practice to improve crop water productivity in a water stressed environments.
NASA Astrophysics Data System (ADS)
Mondal, P.; Jain, M.; DeFries, R. S.; Galford, G. L.; Small, C.
2013-12-01
Agriculture is the largest employment sector in India, where food productivity, and thus food security, is highly dependent on seasonal rainfall and temperature. Projected increase in temperature, along with less frequent but intense rainfall events, will have a negative impact on crop productivity in India in the coming decades. These changes, along with continued ground water depletion, could have serious implications for Indian smallholder farmers, who are among some of the most vulnerable communities to climatic and economic changes. Hence baseline information on agricultural sensitivity to climate variability is important for strategies and policies that promote adaptation to climate variability. This study examines how cropping patterns in different agro-ecological zones in India respond to variations in precipitation and temperature. We specifically examine: a) which climate variables most influence crop cover for monsoon and winter crops? and b) how does the sensitivity of crop cover to climate variability vary in different agro-ecological regions with diverse socio-economic factors? We use remote sensing data (2000-01 - 2012-13) for cropping patterns (developed using MODIS satellite data), climate parameters (derived from MODIS and TRMM satellite data) and agricultural census data. We initially assessed the importance of these climate variables in two agro-ecoregions: a predominantly groundwater irrigated, cash crop region in western India, and a region in central India primarily comprised of rain-fed or surface water irrigated subsistence crops. Seasonal crop cover anomaly varied between -25% and 25% of the 13-year mean in these two regions. Predominantly climate-dependent region in central India showed high anomalies up to 200% of the 13-year crop cover mean, especially during winter season. Winter daytime mean temperature is overwhelmingly the most important climate variable for winter crops irrespective of the varied biophysical and socio-economic conditions across the study regions. Despite access to groundwater irrigation, crop cover in the western Indian study region showed substantial fluctuations during monsoon, probably due to changing planting strategies. This region is less sensitive to precipitation compared to the central Indian study region with predominantly climate-dependent irrigation from surface water. In western Indian study region a greater number of rainy days, increased intensity of rainfall, and cooler daytime and nighttime temperatures lead to increased crop cover during monsoon season, compared to in the central Indian study region where monsoon timing and amount of total rainfall are the most important factors of crop cover. Our findings indicate that different regions respond differently to climate, since socio-economic factors, such as irrigation access, market influences, demography, and policies play critical role in agricultural production. In the wake of projected precipitation and temperature changes, better access to irrigation and heat-tolerant high-yielding crop varieties will be crucial for future food production.
Longevity of shallow subsurface drip irrigation tubing under three tillage practices
USDA-ARS?s Scientific Manuscript database
Shallow Sub-Surface drip irrigation (S3DI) has drip tubing buried about 2-in below the soil surface. It is unknown how long drip tubing would be viable at this shallow soil depth using strip- or no-tillage systems. The objectives were to determine drip tube longevity, resultant crop yield, and parti...
USDA-ARS?s Scientific Manuscript database
Use of furrow irrigation in row crop production is a common practice through much of the Midsouth US and yet, nutrients can be transported off-site through surface runoff. A field study with cotton (Gossypium hirsutum, L.) was conducted to understand the impact of furrow tillage practices and nitrog...
Monaghan, J M; Hutchison, M L
2012-05-01
To improve our understanding of the survival and splash-mediated transfer of zoonotic agents and faecal indicator bacteria introduced into soils used for crop cultivation via contaminated irrigation waters. Zoonotic agents and an Escherichia coli marker bacterium were inoculated into borehole water, which was applied to two different soil types in early-, mid- and late summer. Decline of the zoonotic agents was influenced by soil type. Marker bacteria applied to columns of two soil types in irrigation water did not concentrate at the surface of the soils. Decline of zoonotic agents at the surface was influenced by soil type and environmental conditions. Typically, declines were rapid and bacteria were not detectable after 5 weeks. Selective agar strips were used to determine that the impact of water drops 24-87 μl could splash marker bacteria from soil surfaces horizontal distances of at least 25 cm and heights of 20 cm. Soil splash created by rain-sized water droplets can transfer enteric bacteria from soil to ready-to-eat crops. Persistence of zoonotic agents was reduced at the hottest part of the growing season when irrigation is most likely. Soil splash can cause crop contamination. We report the penetration depths and seasonally influenced declines of bacteria applied in irrigation water into two soil types. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.
Application of an energy balance method for estimating evapotranspiration in cropping systems
USDA-ARS?s Scientific Manuscript database
Accurate quantification of evapotranspiration (ET, consumptive water use) from planting through harvest is critical for managing the limited water resources for crop irrigation. Our objective was to develop and apply an improved land-crop surface residual energy balance (EB) method for quantifying E...
NASA Technical Reports Server (NTRS)
Ozdogan, Mutlu; Rodell, Matthew; Beaudoing, Hiroko Kato; Toll, David L.
2009-01-01
A novel method is introduced for integrating satellite derived irrigation data and high-resolution crop type information into a land surface model (LSM). The objective is to improve the simulation of land surface states and fluxes through better representation of agricultural land use. Ultimately, this scheme could enable numerical weather prediction (NWP) models to capture land-atmosphere feedbacks in managed lands more accurately and thus improve forecast skill. Here we show that application of the new irrigation scheme over the continental US significantly influences the surface water and energy balances by modulating the partitioning of water between the surface and the atmosphere. In our experiment, irrigation caused a 12% increase in evapotranspiration (QLE) and an equivalent reduction in the sensible heat flux (QH) averaged over all irrigated areas in the continental US during the 2003 growing season. Local effects were more extreme: irrigation shifted more than 100 W/m from QH to QLE in many locations in California, eastern Idaho, southern Washington, and southern Colorado during peak crop growth. In these cases, the changes in ground heat flux (QG), net radiation (RNET), evapotranspiration (ET), runoff (R), and soil moisture (SM) were more than 3 W/m(sup 2), 20 W/m(sup 2), 5 mm/day, 0.3 mm/day, and 100 mm, respectively. These results are highly relevant to continental- to global-scale water and energy cycle studies that, to date, have struggled to quantify the effects of agricultural management practices such as irrigation. Based on the results presented here, we expect that better representation of managed lands will lead to improved weather and climate forecasting skill when the new irrigation scheme is incorporated into NWP models such as NOAA's Global Forecast System (GFS).
USDA-ARS?s Scientific Manuscript database
Introduction: Surface and non-traditional irrigation water (SNIW) sources can increase the irrigation water supplies without consuming potable water. However, these sources must be evaluated for enteric pathogens that could adulterate crops intended for human consumption and comply with Food Safety ...
Irrigation water use for the Fort Lyon Canal, southeastern Colorado, 1989-90
Dash, R.G.
1995-01-01
The U.S. Geological Survey, in cooperation with the Bent County Board of County Commissioners, began a study to evaluate irrigation water use quanti- tatively for about 91,630 acres of farmland irrigated from the 103.7-mile-long Fort Lyon Main Canal in the Arkansas River Valley of southeastern Colorado. This report provides information from 1980 and 1990 for four hydrologic components of irrigation water use: Surface-water withdrawals, conveyance losses, ground-water withdrawals, and estimates of threretical crop consumptive use. Surface-water withdrawals for the Fort Lyon Canal were 211,150 acre-feet (about 2.3 acre-feet per acre) during 1989 and 202,000 acre-feet (about 2.2 acre-feet per acre) during 1990. Conveyance losses occurred during the transport of water in the unlined Fort Lyon Canal. Conveyance losses were as much as 72 (acre-feet per day) per mile in the first division of the canal and generally decreased in the downstream canal divisions. Ground-water withdrawals for the Fort Lyon Canal were estimated to be 38,890 acre-feet (about 0.8 acre-foot per acre irrigated ground water) during 1989 and 33,970 acre-feet (about 0.7 acre-foot per acre irrigated by ground water) during 1990. Theoretical crop consumptive use was estimated to be 227,530 acre-feet (about 2.7 acre-feet per acre of cropland) during 1989 and 251, 130 acre-feet (about 2.9 acre-feet per acre of cropland) during 1990. The total crop irrigation requirement needed from irrigation withdrawals was 172,100 acre-feet (about 2.0 acre-feet per acre of cropland) during ` 1989 and 190,050 acre-feet (about 2.2 acre-feet per acre of cropland) during 1990. Crops cultivted in the five divisions of the canal were alfalfa, sorghum, corn, wheat, pasture, and spring grains.
Senay, G.B.; Budde, Michael; Verdin, J.P.; Melesse, Assefa M.
2007-01-01
Accurate crop performance monitoring and production estimation are critical for timely assessment of the food balance of several countries in the world. Since 2001, the Famine Early Warning Systems Network (FEWS NET) has been monitoring crop performance and relative production using satellite-derived data and simulation models in Africa, Central America, and Afghanistan where ground-based monitoring is limited because of a scarcity of weather stations. The commonly used crop monitoring models are based on a crop water-balance algorithm with inputs from satellite-derived rainfall estimates. These models are useful to monitor rainfed agriculture, but they are ineffective for irrigated areas. This study focused on Afghanistan, where over 80 percent of agricultural production comes from irrigated lands. We developed and implemented a Simplified Surface Energy Balance (SSEB) model to monitor and assess the performance of irrigated agriculture in Afghanistan using a combination of 1-km thermal data and 250m Normalized Difference Vegetation Index (NDVI) data, both from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. We estimated seasonal actual evapotranspiration (ETa) over a period of six years (2000-2005) for two major irrigated river basins in Afghanistan, the Kabul and the Helmand, by analyzing up to 19 cloud-free thermal and NDVI images from each year. These seasonal ETa estimates were used as relative indicators of year-to-year production magnitude differences. The temporal water-use pattern of the two irrigated basins was indicative of the cropping patterns specific to each region. Our results were comparable to field reports and to estimates based on watershed-wide crop water-balance model results. For example, both methods found that the 2003 seasonal ETa was the highest of all six years. The method also captured water management scenarios where a unique year-to-year variability was identified in addition to water-use differences between upstream and downstream basins. A major advantage of the energy-balance approach is that it can be used to quantify spatial extent of irrigated fields and their water-use dynamics without reference to source of water as opposed to a water-balance model which requires knowledge of both the magnitude and temporal distribution of rainfall and irrigation applied to fields. ?? 2007 by MDPI.
Senay, Gabriel B.; Budde, Michael; Verdin, James P.; Melesse, Assefa M.
2007-01-01
Accurate crop performance monitoring and production estimation are critical for timely assessment of the food balance of several countries in the world. Since 2001, the Famine Early Warning Systems Network (FEWS NET) has been monitoring crop performance and relative production using satellite-derived data and simulation models in Africa, Central America, and Afghanistan where ground-based monitoring is limited because of a scarcity of weather stations. The commonly used crop monitoring models are based on a crop water-balance algorithm with inputs from satellite-derived rainfall estimates. These models are useful to monitor rainfed agriculture, but they are ineffective for irrigated areas. This study focused on Afghanistan, where over 80 percent of agricultural production comes from irrigated lands. We developed and implemented a Simplified Surface Energy Balance (SSEB) model to monitor and assess the performance of irrigated agriculture in Afghanistan using a combination of 1-km thermal data and 250-m Normalized Difference Vegetation Index (NDVI) data, both from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. We estimated seasonal actual evapotranspiration (ETa) over a period of six years (2000-2005) for two major irrigated river basins in Afghanistan, the Kabul and the Helmand, by analyzing up to 19 cloud-free thermal and NDVI images from each year. These seasonal ETa estimates were used as relative indicators of year-to-year production magnitude differences. The temporal water-use pattern of the two irrigated basins was indicative of the cropping patterns specific to each region. Our results were comparable to field reports and to estimates based on watershed-wide crop water-balance model results. For example, both methods found that the 2003 seasonal ETa was the highest of all six years. The method also captured water management scenarios where a unique year-to-year variability was identified in addition to water-use differences between upstream and downstream basins. A major advantage of the energy-balance approach is that it can be used to quantify spatial extent of irrigated fields and their water-use dynamics without reference to source of water as opposed to a water-balance model which requires knowledge of both the magnitude and temporal distribution of rainfall and irrigation applied to fields.
The reuse of treated wastewater for agricultural purposes in Nicaragua; Central America.
Platzer, M; Cáceres, V; Fong, N
2004-01-01
The first subsurface flow wetland (SSFW) system for about 1,000 PE, was constructed in Nicaragua in 1996 to apply this technology in the form of an integral project, combining the treatment of domestic wastewater with its reuse for crop production in small and medium size communities. The SSFW-effluent meets all standards established in the national regulations for wastewater reuse in agriculture, except for faecal coliforms, existent at an average concentration of 7 x 10(4) MPN/100 ml. A conventional surface irrigation method was used to irrigate different crop species selected to establish their risk of contamination. To judge the potential health risk for consumers and farmers, samples of vegetables and fruits harvested in the dry seasons of the years 1997 to 2002, were analyzed for the presence of pathogenic microorganisms like faecal coliforms, salmonella and shigella. In addition, a yield comparison between crops irrigated with well water using chemical fertilizers, and crops irrigated with the effluent of the SSFW-system was made, to analyze the economical benefits of the wastewater reuse.
Potentials and problems of sustainable irrigation with water high in salts
NASA Astrophysics Data System (ADS)
Ben-Gal, Alon
2015-04-01
Water scarcity and need to expand agricultural productivity have led to ever growing utilization of poor quality water for irrigation of crops. Almost in all cases, marginal or alternative water sources for irrigation contain relatively high concentrations of dissolved salts. When salts are present, irrigation water management, especially in the dry regions where water requirements are highest, must consider leaching in addition to crop evapotranspiration requirements. Leaching requirements for agronomic success are calculable and functions of climate, soil, and very critically, of crop sensitivity and the actual salinity of the irrigation water. The more sensitive the crop and more saline the water, the higher the agronomic cost and the greater the quantitative need for leaching. Israel is a forerunner in large-scale utilization of poor quality water for irrigation and can be used as a case study looking at long term repercussions of policy alternatively encouraging irrigation with recycled water or brackish groundwater. In cases studied in desert conditions of Israel, as much of half of the water applied to crops including bell peppers in greenhouses and date palms is actually used to leach salts from the root zone. The excess water used to leach salts and maintain agronomic and economic success when irrigating with water containing salts can become an environmental hazard, especially in dry areas where natural drainage is non-existent. The leachate often contains not only salts but also agrochemicals including nutrients, and natural contaminants can be picked up and transported as well. This leachate passes beyond the root zone and eventually reaches ground or surface water resources. This, together with evidence of ongoing increases in sodium content of fresh produce and increased SAR levels of soils, suggest that the current policy and practice in Israel of utilization of high amounts of low quality irrigation water is inherently non- sustainable. Current trends and technologies allowing economically feasible desalination at large scales present a sustainable alternative where salts are removed from water prior to irrigation.
NASA Astrophysics Data System (ADS)
Eckert, Jerry B.; Wang, Erda
1993-02-01
Farms in NE Conejos County, Colorado, are characterized by limited resources, uncertain surface flow irrigation systems, and mixed crop-livestock enterprise combinations which are dependent on public grazing resources. To model decision making on these farms, a linear program is developed stressing enterprise choices under conditions of multiple resource constraints. Differential access to grazing resources and irrigation water is emphasized in this research. Regarding the water resource, the model reflects farms situated alternatively on high-, medium-, and low-priority irrigation ditches within the Alamosa-La Jara river system, each with and without supplemental pumping. Differences are found in optimum enterprise mixes, net returns, choice of cropping technology, level of marketings, and other characteristics in response to variations in the availability of irrigation water. Implications are presented for alternative improvement strategies.
NASA Astrophysics Data System (ADS)
Malbéteau, Y.; Lopez, O.; Houborg, R.; McCabe, M.
2017-12-01
Agriculture places considerable pressure on water resources, with the relationship between water availability and food production being critical for sustaining population growth. Monitoring water resources is particularly important in arid and semi-arid regions, where irrigation can represent up to 80% of the consumptive uses of water. In this context, it is necessary to optimize on-farm irrigation management by adjusting irrigation to crop water requirements throughout the growing season. However, in situ point measurements are not routinely available over extended areas and may not be representative at the field scale. Remote sensing approaches present as a cost-effective technique for mapping and monitoring broad areas. By taking advantage of multi-sensor remote sensing methodologies, such as those provided by MODIS, Landsat, Sentinel and Cubesats, we propose a new method to estimate irrigation input at pivot-scale. Here we explore the development of crop-water use estimates via these remote sensing data and integrate them into a land surface modeling framework, using a farm in Saudi Arabia as a demonstration of what can be achieved at larger scales.
Impact of irrigation over India on the land surface fluxes
NASA Astrophysics Data System (ADS)
de Rosnay, P. R.; Polcher, J. P.; Laval, K. L.; Sabre, M. S.
2003-04-01
Irrigation is the main water user in the world with 87 % of the global water consumption being attributed to use on irrigated crop land. There are large spatial variations of the irrigated areas, from 68 % in Asia and 16 % in America, 10 % in Europe and the remaining in Africa and Australia. India is the most important irrigating country in the world with a gross irrigation requirement estimated by the FAO at 457 cubic km by year. The environmental impacts of irrigation are very important: irrigation causes the soil salinization, it affects the water quality and ecology, and increases the incidence of water related diseases. Irrigation is also expected to affect the the land surface energy budget, and thereby the climate system. The work presented here is conducted in the framework of the PROMISE European project. It aims to analyze the sensitivity of the land surface fluxes to the intensive irrigation over Indian peninsula. Numerical experiments are conducted with the land surface scheme ORCHIDEE of the Laboratoire de Meteorologie Dynamique, with a 1 degree spatial resolution. Two 2years simulations, forced by the ISLSCP (1987-88) data sets, are compared, with and without irrigation. The analysis focuses on the effect of land irrigation on the surface fluxes (partition of energy between latent and sensible fluxes), and the river flow.
Uptake and Accumulation of Pharmaceuticals in Overhead- and Surface-Irrigated Greenhouse Lettuce.
Bhalsod, Gemini D; Chuang, Ya-Hui; Jeon, Sangho; Gui, Wenjun; Li, Hui; Ryser, Elliot T; Guber, Andrey K; Zhang, Wei
2018-01-31
Understanding the uptake and accumulation of pharmaceuticals in vegetables under typical irrigation practices is critical to risk assessment of crop irrigation with reclaimed water. This study investigated the pharmaceutical residues in greenhouse lettuce under overhead and soil-surface irrigations using pharmaceutical-contaminated water. Compared to soil-surface irrigation, overhead irrigation substantially increased the pharmaceutical residues in lettuce shoots. The increased residue levels persisted even after washing for trimethoprim, monensin sodium, and tylosin, indicating their strong sorption to the shoots. The postwashing concentrations in fresh shoots varied from 0.05 ± 0.04 μg/kg for sulfadiazine to 345 ± 139 μg/kg for carbamazepine. Root concentration factors ranged from 0.04 ± 0.14 for tylosin to 19.2 ± 15.7 for sulfamethoxazole. Translocation factors in surface-irrigated lettuce were low for sulfamethoxalzole, trimethoprim, monensin sodium, and tylosin (0.07-0.15), but high for caffeine (4.28 ± 3.01) and carbamazepine (8.15 ± 2.87). Carbamazepine was persistent in soil and hyperaccumulated in shoots.
Remotely sensed high resolution irrigated area mapping in India for 2000 to 2015
Ambika, Anukesh Krishnankutty; Wardlow, Brian; Mishra, Vimal
2016-01-01
India is among the countries that uses a significant fraction of available water for irrigation. Irrigated area in India has increased substantially after the Green revolution and both surface and groundwater have been extensively used. Under warming climate projections, irrigation frequency may increase leading to increased irrigation water demands. Water resources planning and management in agriculture need spatially-explicit irrigated area information for different crops and different crop growing seasons. However, annual, high-resolution irrigated area maps for India for an extended historical record that can be used for water resources planning and management are unavailable. Using 250 m normalized difference vegetation index (NDVI) data from Moderate Resolution Imaging Spectroradiometer (MODIS) and 56 m land use/land cover data, high-resolution irrigated area maps are developed for all the agroecological zones in India for the period of 2000–2015. The irrigated area maps were evaluated using the agricultural statistics data from ground surveys and were compared with the previously developed irrigation maps. High resolution (250 m) irrigated area maps showed satisfactory accuracy (R2=0.95) and can be used to understand interannual variability in irrigated area at various spatial scales. PMID:27996974
Evaluating Impacts of Land Use/Land Cover Change on Water Resources in Semiarid Regions
NASA Astrophysics Data System (ADS)
Scanlon, B. R.; Faunt, C. C.; Pool, D. R.; Reedy, R. C.
2017-12-01
Land use/land cover (LU/LC) changes play an integral role in water resources by controlling the partitioning of water at the land surface. Here we evaluate impacts of changing LU/LC on water resources in response to climate variation and change and land use change related to agriculture using data from semiarid regions in the southwestern U.S. Land cover changes in response to climate can amplify or dampen climate impacts on water resources. Changes from wet Pleistocene to much drier Holocene climate resulted in expansion of perennial vegetation, amplifying climate change impacts on water resources by reducing groundwater recharge as shown in soil profiles in the southwestern U.S.. In contrast, vegetation response to climate extremes, including droughts and floods, dampen impacts of these extremes on water resources, as shown by water budget monitoring in the Mojave Desert. Agriculture often involves changes from native perennial vegetation to annual crops increasing groundwater recharge in many semiarid regions. Irrigation based on conjunctive use of surface water and groundwater increases water resource availability, as shown in the Central Valley of California and in southern Arizona. Surface water irrigation in these regions is enhanced by water transported from more humid settings through extensive pipelines. These projects have reversed long-term declining groundwater trends in some regions. While irrigation design has often focused on increased efficiency, "more crop per drop", optimal water resource management may benefit more from inefficient (e.g. flood irrigation) surface-water irrigation combined with efficient (e.g. subsurface drip) irrigation to maximize groundwater recharge, as seen in parts of the Central Valley. Flood irrigation of perennial crops, such as almonds and vineyards, during winter is being considered in the Central Valley to enhance groundwater recharge. Managed aquifer recharge can be considered a special case of conjunctive use of surface water and groundwater use where spreading basins focus recharge in southern California and Arizona. This overview highlights the importance of changes in LU/LC in controlling water budgets in semiarid regions. Understanding these controls should allow us to better manage water resources.
Land use policy and agricultural water management of the previous half of century in Africa
NASA Astrophysics Data System (ADS)
Valipour, Mohammad
2015-12-01
This paper examines land use policy and agricultural water management in Africa from 1962 to 2011. For this purpose, data were gathered from Food and Agriculture Organization of the United Nations (FAO) and the World Bank Group. Using the FAO database, ten indices were selected: permanent crops to cultivated area (%), rural population to total population (%), total economically active population in agriculture to total economically active population (%), human development index, national rainfall index (mm/year), value added to gross domestic product by agriculture (%), irrigation water requirement (mm/year), percentage of total cultivated area drained (%), difference between national rainfall index and irrigation water requirement (mm/year), area equipped for irrigation to cultivated area or land use policy index (%). These indices were analyzed for all 53 countries in the study area and the land use policy index was estimated by two different formulas. The results show that value of relative error is <20 %. In addition, an average index was calculated using various methods to assess countries' conditions for agricultural water management. Ability of irrigation and drainage systems was studied using other eight indices with more limited information. These indices are surface irrigation (%), sprinkler irrigation (%), localized irrigation (%), spate irrigation (%), agricultural water withdrawal (10 km3/year), conservation agriculture area as percentage of cultivated area (%), percentage of area equipped for irrigation salinized (%), and area waterlogged by irrigation (%). Finally, tendency of farmers to use irrigation systems for cultivated crops has been presented. The results show that Africa needs governments' policy to encourage farmers to use irrigation systems and raise cropping intensity for irrigated area.
Jones, Lisa A.; Worobo, Randy W.
2014-01-01
In the United States, surface water is commonly used to irrigate a variety of produce crops and can harbor pathogens responsible for food-borne illnesses and plant diseases. Understanding when pathogens infest water sources is valuable information for produce growers to improve the food safety and production of these crops. In this study, prevalence data along with regression tree analyses were used to correlate water quality parameters (pH, temperature, turbidity), irrigation site properties (source, the presence of livestock or fowl nearby), and precipitation data to the presence and concentrations of Escherichia coli, Salmonella spp., and hymexazol-insensitive (HIS) oomycetes (Phytophthora and Pythium spp.) in New York State surface waters. A total of 123 samples from 18 sites across New York State were tested for E. coli and Salmonella spp., of which 33% and 43% were positive, respectively. Additionally, 210 samples from 38 sites were tested for HIS oomycetes, and 88% were found to be positive, with 10 species of Phytophthora and 11 species of Pythium being identified from the samples. Regression analysis found no strong correlations between water quality parameters, site factors, or precipitation to the presence or concentration of E. coli in irrigation sources. For Salmonella, precipitation (≤0.64 cm) 3 days before sampling was correlated to both presence and the highest counts. Analyses for oomycetes found creeks to have higher average counts than ponds, and higher turbidity levels were associated with higher oomycete counts. Overall, information gathered from this study can be used to better understand the food safety and plant pathogen risks of using surface water for irrigation. PMID:24878603
Transferability Of DEMETER. A Case Study Of The Irrigation Scheme Of Veiga De Chaves
NASA Astrophysics Data System (ADS)
Baptista, A.; Sousa, V.
2006-08-01
DEMETER is a research and demonstration project, designed to assess and demonstrate how the integration of Earth Observation techniques in routine Irrigation Advisory Services can improve efficiency in the use of irrigation water. The objectives of this paper are: (1) to analyze the interest in the feasibility of transferring the DEMETER technology to the irrigation scheme of Chaves: (2) to identify the factors that, in general, favour the usefulness of this technology. The irrigation infrastructure and methods, the size and number of irrigation parcels and the main crops grown at the irrigation scheme of Chaves have been recorded. Also a socio-economic description has been done. Field visits, interviews with the staff of water association, and an inquiry to a sample of 107 farmers were made. The main results are: each farmer pays an area based annual fee, independent of the amount of water used for irrigation; most of the irrigated parcels are of very small size, 0.3 ha in average, mostly irrigated by surface methods; the most representative crops grown are potato, forage maize, and several different horticultural crops; an important part of the production is for self-consumption. The farmers are aging and the new generations prefer other jobs than agriculture. A considerable number of farmers have another job in the nearby cities. The small size of the irrigated parcels limits the use of earth observation technologies to expensive high space resolution images. For the time being, farmers do not feel the need for an irrigation advisory service, manly because there is plenty of water which is not bought proportionally to its use. However, circumstances are changing rapidly and, relatively new for the region, environmental concerns related with irrigation, manly nitrate leaching by excess watering of crops prompts the need for an irrigation advisory service in order to maintain crop production with a more rational use of water. The DEMETER technology could be a suitable solution in certain contexts and types of irrigation systems, in particular in those regions that have (1) a growing agricultural sector, with large scale plots under monoculture, or with only 2 or 3 clearly market-oriented main crops with high potential value-added; (2) where water is scarce and relatively expensive; (3) where consumers pay for the water they use and are organized in a dynamic, well equipped, well-staffed, financially sound and empowering water users associations.
NASA Astrophysics Data System (ADS)
Liu, Cheng-Hua; Zhang, Yingjie; Bhalsod, Gemini; Chuang, Ya-Hui; Boyd, Stephen; Teppen, Brian; Tiedje, James; Li, Hui; Zhang, Wei
2016-04-01
Pharmaceuticals are emerging contaminants widely detected in soil and water environments, and concerns are mounting over their potential impact on human and ecosystem health. In particular, overuse of antibiotics (an important group of pharmaceuticals) in human medicine and animal agriculture and rapid emergence of antibiotic resistant bacteria on a global scale are threatening the health of humans, animals, and the environment. We have investigated interactions of pharmaceuticals with pyrogenic carbon geosorbents (e.g., biohar and activated carbon), bacteria, and vegetable crops in order to better understand sorption, uptake, and translocation of pharmaceuticals in the soil-water-biota continuum. Sorption of antibiotics by biochars was studied to assess the effect of biochar soil amendment in reducing the transport and bioavailability of antibiotics. Pyrogenic carbonaceous materials such as biochars and activated carbon had strong sorption capacities for antibiotics, and drastically lowed the uptake of antibiotics by an Escherichia coli, therefore demonstrating soil amendment with pyrogenic carbon geosorbents as an effective remediation strategy to reduce antibiotic transport and selection pressure for antibiotic resistant bacteria. Additionally, because consuming pharmaceutical-tainted food is a direct human exposure pathway, it is critical to investigate the residue levels of pharmaceuticals in food crops grown in contaminated soils or irrigated with reclaimed water. Therefore, we have studied the uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under overhead or surface irrigations. Preliminary results indicate that pharmaceuticals of large molecular weight and low water solubility had greater concentrations in lettuce shoots under overhead irrigation than surface irrigation. Pharmaceuticals of low molecular weight and high water solubility are less clearly influenced by irrigation methods. These results implies that irrigation scheme needs to be optimized when using the reclaimed water for crop irrigation. In summary, scientifically-sound soil and water management practices are needed to minimize the transfer of pharmaceuticals from soil and water to crops and microorganisms.
A process-based agricultural model for the irrigated agriculture sector in Alberta, Canada
NASA Astrophysics Data System (ADS)
Ammar, M. E.; Davies, E. G.
2015-12-01
Connections between land and water, irrigation, agricultural productivity and profitability, policy alternatives, and climate change and variability are complex, poorly understood, and unpredictable. Policy assessment for agriculture presents a large potential for development of broad-based simulation models that can aid assessment and quantification of policy alternatives over longer temporal scales. The Canadian irrigated agriculture sector is concentrated in Alberta, where it represents two thirds of the irrigated land-base in Canada and is the largest consumer of surface water. Despite interest in irrigation expansion, its potential in Alberta is uncertain given a constrained water supply, significant social and economic development and increasing demands for both land and water, and climate change. This paper therefore introduces a system dynamics model as a decision support tool to provide insights into irrigation expansion in Alberta, and into trade-offs and risks associated with that expansion. It is intended to be used by a wide variety of users including researchers, policy analysts and planners, and irrigation managers. A process-based cropping system approach is at the core of the model and uses a water-driven crop growth mechanism described by AquaCrop. The tool goes beyond a representation of crop phenology and cropping systems by permitting assessment and quantification of the broader, long-term consequences of agricultural policies for Alberta's irrigation sector. It also encourages collaboration and provides a degree of transparency that gives confidence in simulation results. The paper focuses on the agricultural component of the systems model, describing the process involved; soil water and nutrients balance, crop growth, and water, temperature, salinity, and nutrients stresses, and how other disciplines can be integrated to account for the effects of interactions and feedbacks in the whole system. In later stages, other components such as livestock production systems and agricultural production economics will be integrated to the agricultural model to make the systems tool. It will capture feedback loops, time delays, and the nonlinearities of the system. Moreover, the model is designed for quick reconfiguration to different regions given parametrized crop data.
Adaptability of Irrigation to a Changing Monsoon in India: How far can we go?
NASA Astrophysics Data System (ADS)
Zaveri, E.; Grogan, D. S.; Fisher-Vanden, K.; Frolking, S. E.; Wrenn, D. H.; Nicholas, R.
2014-12-01
Agriculture and the monsoon are inextricably linked in India. A large part of the steady rise in agricultural production since the onset of the Green Revolution in the 1960's has been attributed to irrigation. Irrigation is used to supplement and buffer crops against precipitation shocks, but water availability for such use is itself sensitive to the erratic, seasonal and spatially heterogeneous nature of the monsoon. We provide new evidence on the relationship between monsoon changes, irrigation variability and water availability by linking a process based hydrology model with an econometric model for one of the world's most water stressed countries. India uses more groundwater for irrigation than any other country, and there is substantial evidence that this has led to depletion of groundwater aquifers. First, we build an econometric model of historical irrigation decisions using detailed agriculture and weather data spanning 35 years. Multivariate regression models reveal that for crops grown in the wet season, irrigation is sensitive to distribution and total monsoon rainfall but not to ground or surface water availability. For crops grown in the dry season, total monsoon rainfall matters most, and its effect is sensitive to groundwater availability. The historical estimates from the econometric model are used to calculate future irrigated areas under three different climate model predictions of monsoon climate for the years 2010 - 2050. These projections are then used as input to a physical hydrology model, which quantifies supply of irrigation water from sustainable sources such as rechargeable shallow groundwater, rivers and reservoirs, to unsustainable sources such as non- rechargeable groundwater. We find that the significant variation in monsoon projections lead to very different results. Crops grown in the dry season show particularly divergent trends between model projections, leading to very different groundwater resource requirements.
NASA Astrophysics Data System (ADS)
Multsch, Sebastian; Alquwaizany, Abdulaziz S.; Lehnert, Karl-H.; Frede, Hans-Georg; Breuer, Lutz
2015-04-01
The agriculture sector consumes with 88 % a majority of the almost fossil water resources in the Kingdom of Saudi Arabia (KSA). Irrigation with saline water has been highlighted to be a promising technique to reduce fresh water consumption. Current desalination techniques, further developments, salt tolerant crop types and improved irrigation systems can potentially redesign future perspectives for irrigation agriculture, in particular by considering the growing desalination capacity in KSA (5 million m3 day-1 in 2003). Hence, we have analyzed the potential of using desalinated and partial desalinated seawater for growing crops in KSA by considering scenarios of salinity levels and desalination costs. The desalination process has been modelled with the ROSA© software considering a reverse osmosis (RO) plant. The spatial decision support system SPARE:WATER has been applied to assess the water footprint of crops (WFcrop). In order to maintain high crop yields, salts need to be washed out from the rooting zone, which requires the application of additional salt-free water. Therefore, high crop yields come along with additional water requirements and increased desalination effort and increased costs for proving high quality water. As an example, growing wheat with partial desalinated seawater from the Arabian Gulf with a RO plant has been investigated. Desalination reduces the salinity level from 76 dS m-1 to 0.5 dS m-1 considering two RO cycles, with cost of desalinized water in the range of 0.5 to 1.2 m-3. We acknowledge that cost only refer to desalination without considering others such as transport, water pumping or crop fertilization. The study shows that Boron is the most problematic salt component, because it is difficult to remove by RO and toxic in high concentrations for crops (wheat threshold of 0.5 to 1.0 mg l-1). The nationwide average WFcrop of wheat under surface irrigation is 2,628 m3 t-1 considering high water quality of 1 dS m-1 and 3,801 m3 t-1 at 12 dS m-1. Using sprinkler or drip irrigation systems the WFcrop decreases of about 20 % and 34 %, respectively. It can be shown that a salinity level larger than 9 dS m-1 increases leaching water requirement of wheat over proportional and that a salinity level of 9 dS m-1 reduces cost for irrigation water by about 11 % in comparison to the irrigation with nearly fresh water quality of 1 dS m-1. A trade-off analyses reveals that making desalinated seawater use profitable, cost need to be reduced below 0.2 m-3 for sprinkler and drip irrigation and even below 0.1 m-3 for widespread used surface irrigation systems. The authors gratefully acknowledge the support of the King Abdulaziz City for Science and Technology (KACST), Saudi Arabia, for funding the research Project No. 33-900 entitled 'Technology for desalinated seawater use in agriculture'.
Integrating Water Supply Constraints into Irrigated Agricultural Simulations of California
NASA Technical Reports Server (NTRS)
Winter, Jonathan M.; Young, Charles A.; Mehta, Vishal K.; Ruane, Alex C.; Azarderakhsh, Marzieh; Davitt, Aaron; McDonald, Kyle; Haden, Van R.; Rosenzweig, Cynthia E.
2017-01-01
Simulations of irrigated croplands generally lack key interactions between water demand from plants and water supply from irrigation systems. We coupled the Water Evaluation and Planning system (WEAP) and Decision Support System for Agrotechnology Transfer (DSSAT) to link regional water supplies and management with field-level water demand and crop growth. WEAP-DSSAT was deployed and evaluated over Yolo County in California for corn, rice, and wheat. WEAP-DSSAT is able to reproduce the results of DSSAT under well-watered conditions and reasonably simulate observed mean yields, but has difficulty capturing yield interannual variability. Constraining irrigation supply to surface water alone reduces yields for all three crops during the 1987-1992 drought. Corn yields are reduced proportionally with water allocation, rice yield reductions are more binary based on sufficient water for flooding, and wheat yields are least sensitive to irrigation constraints as winter wheat is grown during the wet season.
NASA Astrophysics Data System (ADS)
Leonard, A.; Flores, A. N.; Han, B.; Som Castellano, R.; Steimke, A.
2016-12-01
Irrigation is an essential component for agricultural production in arid and semi-arid regions, accounting for a majority of global freshwater withdrawals used for human consumption. Since climate change affects both the spatiotemporal demand and availability of water in irrigated areas, agricultural productivity and water efficiency depend critically on how producers adapt and respond to climate change. It is necessary, therefore, to understand the coevolution and feedbacks between humans and agricultural systems. Integration of social and hydrologic processes can be achieved by active engagement with local stakeholders and applying their expertise to models of coupled human-environment systems. Here, we use a process based crop simulation model (EPIC) informed by stakeholder engagement to determine how both farm management and climate change influence regional agricultural water use and production in the Lower Boise River Basin (LBRB) of southwest Idaho. Specifically, we investigate how a shift from flood to sprinkler fed irrigation would impact a watershed's overall agricultural water use under RCP 4.5 and RCP 8.5 climate scenarios. The LBRB comprises about 3500 km2, of which 20% is dedicated to irrigated crops and another 40% to grass/pasture grazing land. Via interviews of stakeholders in the LBRB, we have determined that approximately 70% of irrigated lands in the region are flood irrigated. We model four common crops produced in the LBRB (alfalfa, corn, winter wheat, and sugarbeets) to investigate both hydrologic and agricultural impacts of irrigation and climatic drivers. Factors influencing farmers' decision to switch from flood to sprinkler irrigation include potential economic benefits, external financial incentives, and providing a buffer against future water shortages. These two irrigation practices are associated with significantly different surface water and energy budgets, and large-scale shifts in practice could substantially impact regional hydrologic budgets. This study reports our methodology to integrate perspectives of irrigators into projections of future water use and crop growth in the LBRB. It also highlights the need for more robust social data collection methods in socio-hydrologic studies.
NASA Astrophysics Data System (ADS)
Zhang, W.; Liu, C. H.; Bhalsod, G.; Zhang, Y.; Chuang, Y. H.; Boyd, S. A.; Teppen, B. J.; Tiedje, J. M.; Li, H.
2015-12-01
Pharmaceuticals are contaminants of emerging concern frequently detected in soil and water environments, raising serious questions on their potential impact on human and ecosystem health. Overuse and environmental release of antibiotics (i.e., a group of pharmaceuticals extensively used in human medicine and animal agriculture) pose enormous threats to the health of human, animal, and the environment, due to proliferation of antibiotic resistant bacteria. Recently, we have examined interactions of pharmaceuticals with soil geosorbents, bacteria, and vegetable crops in order to elucidate pathways of sorption, uptake, and translocation of pharmaceuticals across the multiple interfaces in soils. Sorption of pharmaceuticals by biochars was studied to assess the potential of biochar soil amendment for reducing the transport and bioavailability of antibiotics. Our preliminary results show that carbonaceous materials such as biochars and activated carbon had strong sorption capacities for antibiotics, and consequently decreased the uptake and antibiotic resistance gene expression by an Escherichia coli bioreporter. Thus, biochar soil amendment showed the potential for reducing selection pressure on antibiotic resistant bacteria. Additionally, since consumption of pharmaceutical-tainted food is a direct exposure pathway for humans, it is important to assess the uptake and accumulation of pharmaceuticals in food crops grown in contaminated soils or irrigated with reclaimed water. Therefore, we have investigated the uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under contrasting irrigation practices (i.e., overhead or surface irrigations). Preliminary results indicate that greater pharmaceutical concentrations were measured in overhead irrigated lettuce than in surface irrigated lettuce. This could have important implications when selecting irrigation scheme to use the reclaimed water for crop irrigation. In summary, proper soil and water management is needed to minimize the transfer of pharmaceuticals from soil and water to biota.
NASA Astrophysics Data System (ADS)
Forbes, B. T.
2015-12-01
Due to the predominantly arid climate in Arizona, access to adequate water supply is vital to the economic development and livelihood of the State. Water supply has become increasingly important during periods of prolonged drought, which has strained reservoir water levels in the Desert Southwest over past years. Arizona's water use is dominated by agriculture, consuming about seventy-five percent of the total annual water demand. Tracking current agricultural water use is important for managers and policy makers so that current water demand can be assessed and current information can be used to forecast future demands. However, many croplands in Arizona are irrigated outside of areas where water use reporting is mandatory. To estimate irrigation withdrawals on these lands, we use a combination of field verification, evapotranspiration (ET) estimation, and irrigation system qualification. ET is typically estimated in Arizona using the Modified Blaney-Criddle method which uses meteorological data to estimate annual crop water requirements. The Modified Blaney-Criddle method assumes crops are irrigated to their full potential over the entire growing season, which may or may not be realistic. We now use the Operational Simplified Surface Energy Balance (SSEBop) ET data in a remote-sensing and energy-balance framework to estimate cropland ET. SSEBop data are of sufficient resolution (30m by 30m) for estimation of field-scale cropland water use. We evaluate our SSEBop-based estimates using ground-truth information and irrigation system qualification obtained in the field. Our approach gives the end user an estimate of crop consumptive use as well as inefficiencies in irrigation system performance—both of which are needed by water managers for tracking irrigated water use in Arizona.
The future of irrigation on the U.S. Great Plains
USDA-ARS?s Scientific Manuscript database
In the Great Plains, soil and water conservation is being achieved in both dryland and irrigated agricultural systems, and increasingly in combinations of these systems. Limiting tillage has increased the retention of crop residues on the surface and has reduced the evaporative loss of water, making...
Satellite mapping of crop water demand in California
USDA-ARS?s Scientific Manuscript database
Surface delivery of irrigation water in the San Joaquin Valley is becoming increasingly restricted due to urbanization and environmental regulation, and the strain is projected to worsen under most climate change scenarios. Remote sensing technology offers the potential to monitor crop evapotranspi...
NASA Astrophysics Data System (ADS)
Blanc, Elodie; Caron, Justin; Fant, Charles; Monier, Erwan
2017-08-01
While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climate change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO2 fertilization effect compared to an unconstrained GHG emission scenario.
Blanc, Elodie; Caron, Justin; Fant, Charles; Monier, Erwan
2017-08-01
While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climate change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO 2 fertilization effect compared to an unconstrained GHG emission scenario.
Agricultural irrigated land-use inventory for Polk County, Florida, 2016
Marella, Richard L.; Berry, Darbi; Dixon, Joann F.
2017-08-16
An accurate inventory of irrigated crop acreage is not available at the level of resolution needed to better estimate agricultural water use or to project future water demands in many Florida counties. A detailed digital map and summary of irrigated acreage was developed for Polk County, Florida, during the 2016 growing season. This cooperative project between the U.S. Geological Survey and the Office of Agricultural Water Policy of the Florida Department of Agriculture and Consumer Services is part of an effort to improve estimates of water use and projections of future demands across all counties in the State. The irrigated areas were delineated by using land-use data provided by the Florida Department of Agriculture and Consumer Services, along with information obtained from the South and Southwest Florida Water Management Districts consumptive water-use permits. Delineations were field verified between April and December 2016. Attribute data such as crop type, primary water source, and type of irrigation system were assigned to the irrigated areas.The results of this inventory and field verification indicate that during the 2016 growing seasons (spring, summer, fall, and winter), an estimated 88,652 acres were irrigated within Polk County. Of the total field-verified crops, 83,995 acres were in citrus; 2,893 acres were in other non-citrus fruit crops (blueberries, grapes, peaches, and strawberries); 621 acres were in row crops (primarily beans and watermelons); 1,117 acres were in nursery (container and tree farms) and sod production; and 26 acres were in field crops including hay and pasture. Of the total inventoried irrigated acreage within Polk County, 98 percent (86,566 acres) was in the Southwest Florida Water Management District, and the remaining 2 percent (2,086 acres) was in the South Florida Water Management District.About 85,788 acres (96.8 percent of the acreage inventoried) were irrigated by a microirrigation system, including drip, bubblers, and spray emitters. The remaining 3.2 percent of the irrigated acreage was irrigated by a sprinkler system (2,360 acres) or subsurface flood systems (504 acres). Groundwater was the primary source of water used on irrigated acreage (88 percent, or 78,050 acres); the remaining 10,602 acres (12 percent) used groundwater combined with surface water as the irrigation source.The irrigated acreage estimated by the U.S. Geological Survey (USGS) for this 2016 inventory (88,652 acres) is about 11 percent higher than the 79,869 acres estimated by the U.S. Department of Agriculture (USDA) for 2012. Citrus and pasture in Polk County show the biggest difference in irrigated acreage between the USGS and USDA totals. Irrigated citrus acreage inventoried in 2016 by the USGS totaled 83,996 acres, whereas the USDA reported 78,305 acres of citrus in 2012. The USGS identified 6 acres of irrigated pasture and 20 acres of hay, whereas the USDA reported 6,631 acres of irrigated pasture and 1,349 acres of hay for 2012. In general, differences between the 2016 USGS field-verified acreage totals and acreage published by the USDA for 2012 could be due to (1) irrigated acreage for some specific crops increased or decreased substantially during the 4-year interval between 2012 and 2016 because of production or economic changes, (2) the assumption that if an irrigation system was present, it was used in 2016, when in fact some landowners may not have used their irrigation systems during this growing period even if they had a crop in the field, or (3) the amount of irrigated acreage published by the USDA for selected crops may be underestimated as a result of how information is obtained and formulated by the agency during census compilations.
NASA Technical Reports Server (NTRS)
Melton, Forrest S.
2017-01-01
In agricultural regions around the world, threats to water supplies from drought and groundwater depletion are driving increased demand for tools to advance agricultural water use efficiency and support sustainable groundwater management. Satellite mapping of evapotranspiration (ET) from irrigated agricultural lands can provide agricultural producers and water resource managers with information that can be used to both optimize ag water use and improve estimates of groundwater withdrawals for irrigation. We describe the development of two remote sensing-based tools for ET mapping in California, including important lessons in terms of system design, partnership development, and transition to operations. For irrigation management, the integration of satellite data and surface sensor networks to provide timely delivery of information on crop water requirements can make irrigation scheduling more practical, convenient, and accurate.Developed through a partnership between NASA and the CA Department of Water Resources, the Satellite Irrigation Management Support (SIMS) framework integrates satellite data with information from agricultural weather networks to map crop canopy development and crop water requirements at the scale of individual fields. Information is distributed to agricultural producers and water managers via a web-based interface and web data services. SIMS also provides an API that facilitates integration with other irrigation decision support tools, such as CropManage and IrriQuest. Field trials using these integrated tools have shown that they can be used to sustain yields while improving water use efficiency and nutrient management. For sustainable groundwater management, the combination of satellite-derived estimates of ET and data on surface water deliveries for irrigation can increase the accuracy of estimates of groundwater pumping. We are developing an OpenET platform to facilitate access to ET data from multiple models and accelerate operational use of ET data in support of a range of water management applications, including implementation of the Sustainable Groundwater Management Act in CA. By providing a shared basis for decision making, we anticipate that the OpenET platform will accelerate implementation of solutions for sustainable groundwater management.
NASA Astrophysics Data System (ADS)
Melton, F. S.; Huntington, J. L.; Johnson, L.; Guzman, A.; Morton, C.; Zaragoza, I.; Dexter, J.; Rosevelt, C.; Michaelis, A.; Nemani, R. R.; Cahn, M.; Temesgen, B.; Trezza, R.; Frame, K.; Eching, S.; Grimm, R.; Hall, M.
2017-12-01
In agricultural regions around the world, threats to water supplies from drought and groundwater depletion are driving increased demand for tools to advance agricultural water use efficiency and support sustainable groundwater management. Satellite mapping of evapotranspiration (ET) from irrigated agricultural lands can provide agricultural producers and water resource managers with information that can be used to both optimize ag water use and improve estimates of groundwater withdrawals for irrigation. We describe the development of two remote sensing-based tools for ET mapping in California, including important lessons in terms of system design, partnership development, and transition to operations. For irrigation management, the integration of satellite data and surface sensor networks to provide timely delivery of information on crop water requirements can make irrigation scheduling more practical, convenient, and accurate. Developed through a partnership between NASA and the CA Department of Water Resources, the Satellite Irrigation Management Support (SIMS) framework integrates satellite data with information from agricultural weather networks to map crop canopy development and crop water requirements at the scale of individual fields. Information is distributed to agricultural producers and water managers via a web-based interface and web data services. SIMS also provides an API that facilitates integration with other irrigation decision support tools, such as CropManage and IrriQuest. Field trials using these integrated tools have shown that they can be used to sustain yields while improving water use efficiency and nutrient management. For sustainable groundwater management, the combination of satellite-derived estimates of ET and data on surface water deliveries for irrigation can increase the accuracy of estimates of groundwater pumping. We are developing an OpenET platform to facilitate access to ET data from multiple models and accelerate operational use of ET data in support of a range of water management applications, including implementation of the Sustainable Groundwater Management Act in CA. By providing a shared basis for decision making, we anticipate that the OpenET platform will accelerate implementation of solutions for sustainable groundwater management.
NASA Astrophysics Data System (ADS)
Troy, T. J.; Zhang, J.
2017-12-01
Balancing irrigated water demands and surface water availability is critical for sustainable water resources management. In China, irrigation is the largest water user, and there is concern that irrigated water demands will be affected by climate change. If the relationship between climate change, irrigated water demands and surface water availability is quantified, then effective measures can be developed to maintain food production while ensuring water sustainability. This research focuses on the Yellow River, the second longest in China, and analyzes the impact of historical and projected climate change on agricultural water demands and surface water availability. Corn and wheat are selected as representative crops to estimate the effect of temperature and precipitin changes on irrigated water demands. The VIC model is used to simulate daily streamflow throughout the Yellow River, providing estimates of surface water availability. Overall, results indicate the irrigated water need and surface water availability are impacted by climate change, with spatially varying impacts depending on spatial patterns of climate trends and river network position. This research provides insight into water security in the Yellow River basin, indicating where water efficiency measures are needed and where they are not.
Use of treated wastewater in agriculture: effects on soil environment
NASA Astrophysics Data System (ADS)
Levy, Guy J.; Lado, Marcos
2014-05-01
Disposal of treated sewage, both from industrial and domestic origin (herein referred to as treated wastewater [TWW]), is often considered as an environmental hazard. However, in areas afflicted by water scarcity, especially in semi-arid and arid regions, where the future of irrigated agriculture (which produces approximately one third of crop yield and half the return from global crop production) is threatened by existing or expected shortage of fresh water, the use of TWW offers a highly effective and sustainable strategy to exploit a water resource. However, application of TWW to the soil is not free of risks both to organisms (e.g., crops, microbiota) and to the soil. Potential risks may include reduction in biological activity (including crop yield) due to elevated salinity and specific ion toxicity, migration of pollutants towards surface- and ground-water, and deterioration of soil structure. In recent years, new evidence about the possible negative impact of long-term irrigation with TWW on soil structure and physical and chemo-physical properties has emerged, thus putting the sustainability of irrigation with TWW in question. In this presentation, some aspects of the effects of long-term irrigation with TWW on soil properties are shown.
NASA Astrophysics Data System (ADS)
Fulton, A.; Snyder, R.; Hillyer, C.; English, M.; Sanden, B.; Munk, D.
2012-04-01
Enhancing Adoption of Irrigation Scheduling to Sustain the Viability of Fruit and Nut Crops in California Allan Fulton, Richard Snyder, Charles Hillyer, Marshall English, Blake Sanden, and Dan Munk Adoption of scientific methods to decide when to irrigate and how much water to apply to a crop has increased over the last three decades in California. In 1988, less than 4.3 percent of US farmers employed some type of science-based technique to assist in making irrigation scheduling decisions (USDA, 1995). An ongoing survey in California, representing an industry irrigating nearly 0.4 million planted almond hectares, indicates adoption rates ranging from 38 to 55 percent of either crop evapotranspiration (ETc), soil moisture monitoring, plant water status, or some combination of these irrigation scheduling techniques to assist with making irrigation management decisions (California Almond Board, 2011). High capital investment to establish fruit and nut crops, sensitivity to over and under-irrigation on crop performance and longevity, and increasing costs and competition for water have all contributed to increased adoption of scientific irrigation scheduling methods. These trends in adoption are encouraging and more opportunities exist to develop improved irrigation scheduling tools, especially computer decision-making models. In 2009 and 2010, an "On-line Irrigation Scheduling Advisory Service" (OISO, 2012), also referred to as Online Irrigation Management (IMO), was used and evaluated in commercial walnut, almond, and French prune orchards in the northern Sacramento Valley of California. This specific model has many features described as the "Next Generation of Irrigation Schedulers" (Hillyer, 2010). While conventional irrigation management involves simply irrigating as needed to avoid crop stress, this IMO is designed to control crop stress, which requires: (i) precise control of crop water availability (rather than controlling applied water); (ii) quantifying crop stress in order to manage it in heterogeneous fields; and (iii) predicting crop responses to water stress. The capacities of this IMO include: 1. Modeling of the disposition of applied water in spatially variable fields; 2. Conjunctive scheduling for multiple fields, rather than scheduling each field independently; 3. Long range forecasting of crop water requirements to better utilize limited water or limited delivery system capacity: and 4. Explicit modeling of the uncertainties of water use and crop yield. This was one of the first efforts to employ a "Next Generation" type computer irrigation scheduling advisory model or IMO in orchard crops. This paper discusses experiences with introducing this model to fruit and nut growers of various size and scale in the northern Sacramento Valley of California and the accuracy of its forecasts of irrigation needs in fruit and nut crops. Strengths and opportunities to forge ahead in the development of a "Next Generation" irrigation scheduler were identified from this on-farm evaluation.
Fagúndez, Jaime; Olea, Pedro P; Tejedo, Pablo; Mateo-Tomás, Patricia; Gómez, David
2016-07-01
The intensification of agriculture has increased production at the cost of environment and biodiversity worldwide. To increase crop yield in dry cereal systems, vast farmland areas of high conservation value are being converted into irrigation, especially in Mediterranean countries. We analyze the effect of irrigation-driven changes on the farm biota by comparing species diversity, community composition, and species traits of arable plants within crop fields from two contrasting farming systems (dry and irrigated) in Spain. We sampled plant species within 80 fields of dry wheat, irrigated wheat, and maize (only cultivated under irrigation). Wheat crops held higher landscape and per field species richness, and beta diversity than maize. Within the same type of crop, irrigated wheat hosted lower plant diversity than dry wheat at both field and landscape scales. Floristic composition differed between crop types, with higher frequencies of perennials, cosmopolitan, exotic, wind-pollinated and C4 species in maize. Our results suggest that irrigation projects, that transform large areas of dry cereal agro-ecosystems into irrigated crop systems dominated by maize, erode plant diversity. An adequate planning on the type and proportion of crops used in the irrigated agro-ecosystems is needed in order to balance agriculture production and biodiversity conservation.
Blanc, Elodie; Caron, Justin; Fant, Charles; ...
2017-06-27
While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climatemore » change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO 2 fertilization effect compared to an unconstrained GHG emission scenario.« less
Assessment of water use in the Spanish irrigation district "Río Adaja"
NASA Astrophysics Data System (ADS)
Naroua, Illiassou; Rodriguez-Sinobas, Leonor; Sánchez Calvo, Raúl
2013-04-01
Intensive agricultural practices combined with the increasing pressure of urbanization and the changing lifestyles, have strengthened the problems of competing users over limited water resources in a fragile and already stressed environment. Sustainable irrigated agriculture is prescribed as a policy approach that maximizes economic benefits while maintaining environmental quality. Within this framework a proper management of irrigation systems saving water is required. On the other hand, crops with high tolerance to water stress and deficit irrigation are recommended. However, crop yield, among other factors, is very sensitive to water Thus, studies addressing the relations among crop water requirements, irrigation depth and crop yield are necessary. This type of study has been carried out in the Spanish irrigation District "Río Adaja" in the year 2010-2011 with the crops: wheat, barley, sugarbeet, corn, onion, potato, sunflower, clover and carrot. A soil hydrology balance model was applied taking into account climatic data for the nearby weather station and soil characteristics. Effective precipitation was calculated by the index curve number. Crop water requirements were calculated by the FAO Penman-Monteith with the application of the dual crop coefficient. Likewise, productivity was measured by the following indexes: annual relative irrigation supply (ARIS), relative water supply (RWS), relative rainfall supply (RS) and water productivity (WP). Results show that water applied with the irrigation of clover, sugarbeet, corn and onion was less than their water requirements There was a 35 % difference between the amount of water simulated with the model and the gross amount applied during the irrigation period by the irrigation district. WP values differed among crops depending, mainly, on the crop`s market price and the amount of irrigation water. The highest values corresponded to potato and onion crops.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Blanc, Elodie; Caron, Justin; Fant, Charles
While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climatemore » change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO 2 fertilization effect compared to an unconstrained GHG emission scenario.« less
Improving irrigation management in L'Horta Nord (Valencia, Spain)
NASA Astrophysics Data System (ADS)
Pascual-Seva, Nuria; San Bautista, Alberto; López-Galarza, Salvador; Maroto, Jose Vicente; Pascual, Bernardo
2014-05-01
L'Horta Nord is an important irrigation district in Valencia (Spain), especially for vegetable crops. The traditional cropping pattern in the region consists of a rotation of chufa with crops such as potato, onion, lettuce, escarole and red cabbage, being all these crops furrow irrigated. Currently, the quality of the water used is acceptable, water is not expensive and there are no limitations on supply. Consequently, growers are not aware of the volumes of water used, application efficiencies, nor water productivity for any of the crops cited. The European Framework Directive 2000/60, based on the precautionary principle, considers preventive action for measures to be taken; moreover, drought periods are becoming more frequent and extended, and water is being diverted to other uses. Thus, water use is an issue to improve. In this sense, the current situation of the irrigation in the area is analysed using chufa (Cyperus esculentus L. var. sativus Boeck.) as representative of the crops, since most of the crops in the area have shallow root systems, as chufa, which are irrigated in similar patterns. In order to analyse the irrigation performance of the traditional chufa crop as well as to achieve more sustainable results, different studies have been carried out, during the last decade. Efforts have been directed to increase water productivity, increasing yield and minimising the volumes of water applied. Different planting configurations and different irrigation thresholds, not only in furrow irrigation but also in drip irrigation, are examples of how the irrigation performance could be improved. Herein is presented a two-year study, comparing, in both furrow and drip irrigation, two irrigation schedules based on the volumetric soil water content, which was continuously monitored using capacitance sensors. Yield was significantly affected by the growing season, the irrigation system and by the irrigation schedule, and by the second order interactions of the irrigation system with the other studied variables. Greater yields (p≤0.01) were obtained in the first growing season, drip irrigation and maintaining a higher soil moisture level. When considering the irrigation water use efficiency, the irrigation system showed significant differences (p≤0.01) with greater efficiencies for drip irrigation. Considering the homogeneity of the plots in the area and the similarities of the irrigation managements of chufa with the other crops, the results could be extended to most of the plots and crops in the area.
A farm pond water irrigation management system in Mid-South United States
USDA-ARS?s Scientific Manuscript database
In the mid-southern United States, though most states receive more than 1000 mm of annual precipitation, only 20% irrigation is from surface water in this region. The majority of rainfall occurs in fall, winter and spring, but water deficit still exists during crop critical growing season from May t...
NASA Astrophysics Data System (ADS)
Okada, M.; Iizumi, T.; Sakamoto, T.; Kotoku, M.; Sakurai, G.; Nishimori, M.
2017-12-01
Replacing rainfed cropping system by irrigated one is assumed to be an effective measure for climate change adaptation in agriculture. However, in many agricultural impact assessments, future irrigation scenarios are externally given and do not consider variations in the availability of irrigation water under changing climate and land use. Therefore, we assess the potential effects of adaption measure expanding irrigated area under climate change by using a large-scale crop-river coupled model, CROVER [Okada et al. 2015, JAMES]. The CROVER model simulates the large-scale terrestrial hydrological cycle and crop growth depending on climate, soil properties, landuse, crop cultivation management, socio-economic water demand, and reservoir operation management. The bias-corrected GCMs outputs under the RCP 8.5 scenario were used. The future expansion of irrigation area was estimated by using the extrapolation method based on the historical change in irrigated and rainfed areas. As the results, the irrigation adaptation has only a limited effect on the rice production in East Asia due to the conflict of water use for irrigation with the other crops, whose farmlands require unsustainable water extraction with the excessively expanding irrigated area. In contrast, the irrigation adaptation benefits maize production in Europe due to the little conflict of water use for irrigation. Our findings suggest the importance of simulating the river water availability and crop production in a single model for the more realistic assessment in the irrigation adaptation potential effects of crop production under changing climate and land use.
Masoner, J.R.; Mladinich, C.S.; Konduris, A.M.; Smith, S. Jerrod
2003-01-01
Increased demand for water in the Lake Altus drainage basin requires more accurate estimates of water use for irrigation. The U.S. Geological Survey, in cooperation with the U.S. Bureau of Reclamation, is investigating new techniques to improve water-use estimates for irrigation purposes in the Lake Altus drainage basin. Empirical estimates of reference evapotranspiration, crop evapotranspiration, and crop irrigation water requirements for nine major crops were calculated from September 1999 to October 2000 using a solar radiation-based evapotranspiration model. Estimates of irrigation water use were calculated using remotely sensed irrigated crop acres derived from Landsat 7 Enhanced Thematic Mapper Plus imagery and were compared with irrigation water-use estimates calculated from irrigated crop acres reported by the Oklahoma Water Resources Board and the Texas Water Development Board for the 2000 growing season. The techniques presented will help manage water resources in the Lake Altus drainage basin and may be transferable to other areas with similar water management needs. Irrigation water use calculated from the remotely sensed irrigated acres was estimated at 154,920 acre-feet; whereas, irrigation water use calculated from state reported irrigated crop acres was 196,026 acre-feet, a 23 percent difference. The greatest difference in irrigation water use was in Carson County, Texas. Irrigation water use for Carson County, Texas, calculated from the remotely sensed irrigated acres was 58,555 acrefeet; whereas, irrigation water use calculated from state reported irrigated acres was 138,180 acre-feet, an 81 percent difference. The second greatest difference in irrigation water use occurred in Beckham County, Oklahoma. Differences between the two irrigation water use estimates are due to the differences of irrigated crop acres derived from the mapping process and those reported by the Oklahoma Water Resources Board and Texas Water Development Board.
NASA Astrophysics Data System (ADS)
Jain, A. K.; Lin, T. S.; Lawrence, P.; Kheshgi, H. S.
2017-12-01
Environmental factors - characterized by increasing levels of CO2, and changes in temperature and precipitation patterns - present potential risks to global food supply. To date, understanding of environmental factors' effects on crop production remains uncertain due to (1) uncertainties in projected trends of these factors and their spatial and temporal variability; (2) uncertainties in the physiological, genetic and molecular basis of crop adaptation to adaptive management practices (e.g. change in planting time, irrigation and N fertilization etc.) and (3) uncertainties in current land surface models to estimate the response of crop production to changes in environmental factors and management strategies. In this study we apply a process-based land surface model, the Integrated Science Assessment model (ISAM), to assess the impact of various environmental factors and management strategies on the production of row crops (corn, soybean and wheat) at regional and global scales. Results are compared to corresponding simulations performed with the crop model in the Community Land Model (CLM4.5). Each model is driven with historical atmospheric forcing data (1901-2005), and projected atmospheric forcing data under RCP 4.5 or RCP 8.5 (2006-2100) from CESM CMIP5 simulations to estimate the effects of different climate change projections on potential productivity of food crops at a global scale. For each set of atmospheric forcing data, production of each crop is simulated with and without inclusion of adaptive management practices (e.g. application of irrigation, N fertilization, change in planting time and crop cultivars etc.) to assess the effect of adaptation on projected crop production over the 21st century. In detail, three questions are addressed: (1) what is the impact of different climate change projections on global crop production; (2) what is the effect of adaptive management practices on projected crop production; and (3) how do differences in model mechanisms in ISAM and CLM4.5 impact projected global crop production and adaptive management practices (irrigation and N fertilizer) over the 21st century. The major outcomes of this study will help to understand the uncertainties in potential productivity of food crops under different environmental conditions and management practices.
Planning for deficit irrigation
USDA-ARS?s Scientific Manuscript database
Irrigators with limited water supplies that lead to deficit irrigation management need to make decisions about crop selection, water allocations to each crop, and irrigation schedules. Many of these decisions need to occur before the crop is planted and depend on yield-evapotranspiration (ET) and yi...
Online decision support system for surface irrigation management
NASA Astrophysics Data System (ADS)
Wang, Wenchao; Cui, Yuanlai
2017-04-01
Irrigation has played an important role in agricultural production. Irrigation decision support system is developed for irrigation water management, which can raise irrigation efficiency with few added engineering services. An online irrigation decision support system (OIDSS), in consist of in-field sensors and central computer system, is designed for surface irrigation management in large irrigation district. Many functions have acquired in OIDSS, such as data acquisition and detection, real-time irrigation forecast, water allocation decision and irrigation information management. The OIDSS contains four parts: Data acquisition terminals, Web server, Client browser and Communication system. Data acquisition terminals are designed to measure paddy water level, soil water content in dry land, ponds water level, underground water level, and canals water level. A web server is responsible for collecting meteorological data, weather forecast data, the real-time field data, and manager's feedback data. Water allocation decisions are made in the web server. Client browser is responsible for friendly displaying, interacting with managers, and collecting managers' irrigation intention. Communication system includes internet and the GPRS network used by monitoring stations. The OIDSS's model is based on water balance approach for both lowland paddy and upland crops. Considering basic database of different crops water demands in the whole growth stages and irrigation system engineering information, the OIDSS can make efficient decision of water allocation with the help of real-time field water detection and weather forecast. This system uses technical methods to reduce requirements of user's specialized knowledge and can also take user's managerial experience into account. As the system is developed by the Browser/Server model, it is possible to make full use of the internet resources, to facilitate users at any place where internet exists. The OIDSS has been applied in Zhanghe Irrigation District (Center China) to manage the required irrigation deliveries. Two years' application indicates that the proposed OIDSS can achieve promising performance for surface irrigation. Historical data of rice growing period in 2014 has been applied to test the OIDSS: it gives out 3 irrigation decisions, which is consistent with actual irrigation times and the forecast irrigation dates are well fit with the actual situations; the corresponding amount of total irrigation decreases by 15.13% compared to those without using the OIDSS.
Pharmaceuticals in Surface Waters and Potential Transfer to Irrigated Food Crops
A number of pharmaceuticals have been detected in surface waters across the United States. The objective of this study was to evaluate the presence of selected pharmaceuticals (macrolidic antibiotics and pseudoephedrine) and illicit drugs (methamphetamine, Ecstasy) in surface wat...
Role of irrigation and irrigation automation in improving crop water use efficiency
USDA-ARS?s Scientific Manuscript database
In arid climates, irrigation is required for significant agricultural production. In subhumid and semiarid climates, supplemental irrigation is recognized as both economically necessary (prevention of crop losses in periodic droughts) and as a means to improve overall crop water use effi...
NASA Astrophysics Data System (ADS)
Los, Sietse
2017-04-01
Vegetation is water limited in large areas of Spain and therefore a close link exists between vegetation greenness observed from satellite and moisture availability. Here we exploit this link to infer spatial and temporal variability in moisture from MODIS NDVI data and thermal data. Discrepancies in the precipitation - vegetation relationship indicate areas with an alternative supply of water (i.e. not rainfall), this can be natural where moisture is supplied by upwelling groundwater, or can be artificial where crops are irrigated. As a result spatial and temporal variability in vegetation in the La Mancha Plain appears closely linked to topography, geology, rainfall and land use. Crop land shows large variability in year-to-year vegetation greenness; for some areas this variability is linked to variability in rainfall but in other cases this variability is linked to irrigation. The differences in irrigation treatment within one plant functional type, in this case crops, will lead to errors in land surface models when ignored. The magnitude of these effects on the energy, carbon and water balance are assessed at the scale of 250 m to 200 km. Estimating the water balance correctly is of particular important since in some areas in Spain more water is used for irrigation than is supplemented by rainfall.
Assessment of water sources to plant growth in rice based cropping systems by stable water isotopes
NASA Astrophysics Data System (ADS)
Mahindawansha, Amani; Kraft, Philipp; Racela, Heathcliff; Breuer, Lutz
2016-04-01
Rice is one of the most water-consuming crops in the world. Understanding water source utilization of rice will help us to improve water use efficiency (WUE) in paddy management. The objectives of our study are to evaluate the isotopic compositions of surface ponded water, soil water, irrigation water, groundwater, rain water and plant water and based on stable water isotope signatures to evaluate the contributions of various water sources to plant growth (wet rice, aerobic rice and maize) together with investigating the contribution of water from different soil horizons for plant growth in different maturity periods during wet and dry seasons. Finally we will compare the water balances and crop yields in both crops during both seasons and calculate the water use efficiencies. This will help to identify the most efficient water management systems in rice based cropping ecosystems using stable water isotopes. Soil samples are collected from 9 different depths at up to 60 cm in vegetative, reproductive and matured periods of plant growth together with stem samples. Soil and plant samples are extracted by cryogenic vacuum extraction. Root samples are collected up to 60 cm depth from 10 cm intercepts leading calculation of root length density and dry weight. Groundwater, surface water, rain water and irrigation water are sampled weekly. All water samples are analyzed for hydrogen and oxygen isotope ratios (d18O and dD) using Los Gatos Research DLT100. Rainfall records, ground water level, surface water level fluctuations and the amount of water irrigated in each field will be measured during the sampling period. The direct inference approach which is based on comparing isotopic compositions (dD and d18O) between plant stem water and soil water will be used to determine water sources taken up by plant. Multiple-source mass balance assessment can provide the estimated range of potential contributions of water from each soil depth to root water uptake of a crop. These evaluations will be used to determine the proportion of water from upper soil horizons and deep horizons for rice and maize in different maturity periods during wet and dry seasons. Finally we will estimate the influence of groundwater and surface water by irrigation water and/or by precipitation. First results of the sampling during the wet season 2015 will be presented.
Seevers, P.M.; Sadowski, F.C.; Lauer, D.T.
1990-01-01
Retrospective satellite image data were evaluated for their ability to demonstrate the influence of center-pivot irrigation development in western Nebraska on spectral change and climate-related factors for the region. Periodic images of an albedo index and a normalized difference vegetation index (NDVI) were generated from calibrated Landsat multispectral scanner (MSS) data and used to monitor spectral changes associated with irrigation development from 1972 through 1986. The albedo index was not useful for monitoring irrigation development. For the NDVI, it was found that proportions of counties in irrigated agriculture, as discriminated by a threshold, were more highly correlated with reported ground estimates of irrigated agriculture than were county mean greenness values. A similar result was achieved when using coarse resolution Advanced Very High Resolution Radiometer (AVHRR) image data for estimating irrigated agriculture. The NDVI images were used to evaluate a procedure for making areal estimates of actual evapotranspiration (ET) volumes. Estimates of ET volumes for test counties, using reported ground acreages and corresponding standard crop coefficients, were correlated with the estimates of ET volume using crop coefficients scaled to NDVI values and pixel counts of crop areas. These county estimates were made under the assumption that soil water availability was unlimited. For nonirrigated vegetation, this may result in over-estimation of ET volumes. Ground information regarding crop types and acreages are required to derive the NDVI scaling factor. Potential ET, estimated with the Jensen-Haise model, is common to both methods. These results, achieved with both MSS and AVHRR data, show promise for providing climatologically important land surface information for regional and global climate models. ?? 1990 Kluwer Academic Publishers.
NASA Astrophysics Data System (ADS)
Siebert, Stefan; Döll, Petra
2010-04-01
SummaryCrop production requires large amounts of green and blue water. We developed the new global crop water model GCWM to compute consumptive water use (evapotranspiration) and virtual water content (evapotranspiration per harvested biomass) of crops at a spatial resolution of 5' by 5', distinguishing 26 crop classes, and blue versus green water. GCWM is based on the global land use data set MIRCA2000 that provides monthly growing areas for 26 crop classes under rainfed and irrigated conditions for the period 1998-2002 and represents multi-cropping. By computing daily soil water balances, GCWM determines evapotranspiration of blue and green water for each crop and grid cell. Cell-specific crop production under both rainfed and irrigated conditions is computed by downscaling average crop yields reported for 402 national and sub-national statistical units, relating rainfed and irrigated crop yields reported in census statistics to simulated ratios of actual to potential crop evapotranspiration for rainfed crops. By restricting water use of irrigated crops to green water only, the potential production loss without any irrigation was computed. For the period 1998-2002, the global value of total crop water use was 6685 km 3 yr -1, of which blue water use was 1180 km 3 yr -1, green water use of irrigated crops was 919 km 3 yr -1 and green water use of rainfed crops was 4586 km 3 yr -1. Total crop water use was largest for rice (941 km 3 yr -1), wheat (858 km 3 yr -1) and maize (722 km 3 yr -1). The largest amounts of blue water were used for rice (307 km 3 yr -1) and wheat (208 km 3 yr -1). Blue water use as percentage of total crop water use was highest for date palms (85%), cotton (39%), citrus fruits (33%), rice (33%) and sugar beets (32%), while for cassava, oil palm and cocoa, almost no blue water was used. Average crop yield of irrigated cereals was 442 Mg km -2 while average yield of rainfed cereals was only 266 Mg km -2. Average virtual water content of cereal crops was 1109 m 3 Mg -1 of green water and 291 m 3 Mg -1 of blue water, while average crop water productivity of cereal crops was 714 g m -3. If currently irrigated crops were not irrigated, global production of dates, rice, cotton, citrus and sugar cane would decrease by 60%, 39%, 38%, 32% and 31%, respectively. Forty-three per cent of cereal production was on irrigated land, and without irrigation, cereal production on irrigated land would decrease by 47%, corresponding to a 20% loss of total cereal production. The largest cereal production losses would occur in Northern Africa (66%) and Southern Asia (45%) while losses would be very low for Northern Europe (0.001%), Western Europe (1.2%), Eastern Europe (1.5%) and Middle Africa (1.6%). Uncertainties and limitations are discussed in the manuscript, and a comparison of GCWM results to statistics or results of other studies shows good agreement at the regional scale, but larger differences for specific countries.
NASA Astrophysics Data System (ADS)
Chukalla, Abebe D.; Krol, Maarten S.; Hoekstra, Arjen Y.
2018-06-01
Grey water footprint (WF) reduction is essential given the increasing water pollution associated with food production and the limited assimilation capacity of fresh water. Fertilizer application can contribute significantly to the grey WF as a result of nutrient leaching to groundwater and runoff to streams. The objective of this study is to explore the effect of the nitrogen application rate (from 25 to 300 kg N ha-1), nitrogen form (inorganic N or manure N), tillage practice (conventional or no-tillage) and irrigation strategy (full or deficit irrigation) on the nitrogen load to groundwater and surface water, crop yield and the N-related grey water footprint of crop production by a systematic model-based assessment. As a case study, we consider irrigated maize grown in Spain on loam soil in a semi-arid environment, whereby we simulate the 20-year period 1993-2012. The water and nitrogen balances of the soil and plant growth at the field scale were simulated with the Agricultural Policy Environmental eXtender (APEX) model. As a reference management package, we assume the use of inorganic N (nitrate), conventional tillage and full irrigation. For this reference, the grey WF at a usual N application rate of 300 kg N ha-1 (with crop yield of 11.1 t ha-1) is 1100 m3 t-1, which can be reduced by 91 % towards 95 m3 t-1 when the N application rate is reduced to 50 kg N ha-1 (with a yield of 3.7 t ha-1). The grey WF can be further reduced to 75 m3 t-1 by shifting the management package to manure N and deficit irrigation (with crop yield of 3.5 t ha-1). Although water pollution can thus be reduced dramatically, this comes together with a great yield reduction, and a much lower water productivity (larger green plus blue WF) as well. The overall (green, blue and grey) WF per tonne is found to be minimal at an N application rate of 150 kg N ha-1, with manure, no-tillage and deficit irrigation (with crop yield of 9.3 t ha-1). The paper shows that there is a trade-off between grey WF and crop yield, as well as a trade-off between reducing water pollution (grey WF) and water consumption (green and blue WF). Applying manure instead of inorganic N and deficit instead of full irrigation are measures that reduce both water pollution and water consumption with a 16 % loss in yield.
USDA-ARS?s Scientific Manuscript database
Wind erosion is a concern within the Columbia Basin of the Inland Pacific Northwest (PNW) United States due to the sandy texture of soils and small amount of residue retained on the soil surface after harvest of vegetable crops like potato. This study assessed potential wind erosion of an irrigated ...
Stine, Scott W; Song, Inhong; Choi, Christopher Y; Gerba, Charles P
2005-05-01
Microbial contamination of the surfaces of cantaloupe, iceberg lettuce, and bell peppers via contact with irrigation water was investigated to aid in the development of irrigation water quality standards for enteric bacteria and viruses. Furrow and subsurface drip irrigation methods were evaluated with the use of nonpathogenic surrogates, coliphage PRD1, and Escherichia coli ATCC 25922. The concentrations of hepatitis A virus (HAV) and Salmonella in irrigation water necessary to achieve a 1:10,000 annual risk of infection, the acceptable level of risk used for drinking water by the U.S. Environmental Protection Agency, were calculated with a quantitative microbial risk assessment approach. These calculations were based on the transfer of the selected nonpathogenic surrogates to fresh produce via irrigation water, as well as previously determined preharvest inactivation rates of pathogenic microorganisms on the surfaces of fresh produce. The risk of infection was found to be variable depending on type of crop, irrigation method, and days between last irrigation event and harvest. The worst-case scenario, in which produce is harvested and consumed the day after the last irrigation event and maximum exposure is assumed, indicated that concentrations of 2.5 CFU/100 ml of Salmonella and 2.5 x 10(-5) most probable number per 100 ml of HAV in irrigation water would result in an annual risk of 1:10,000 when the crop was consumed. If 14 days elapsed before harvest, allowing for die-off of the pathogens, the concentrations were increased to 5.7 x 10(3) Salmonella per 100 ml and 9.9 x 10(-3) HAV per 100 ml.
Estimating irrigation water use in the humid eastern United States
Levin, Sara B.; Zarriello, Phillip J.
2013-01-01
Accurate accounting of irrigation water use is an important part of the U.S. Geological Survey National Water-Use Information Program and the WaterSMART initiative to help maintain sustainable water resources in the Nation. Irrigation water use in the humid eastern United States is not well characterized because of inadequate reporting and wide variability associated with climate, soils, crops, and farming practices. To better understand irrigation water use in the eastern United States, two types of predictive models were developed and compared by using metered irrigation water-use data for corn, cotton, peanut, and soybean crops in Georgia and turf farms in Rhode Island. Reliable metered irrigation data were limited to these areas. The first predictive model that was developed uses logistic regression to predict the occurrence of irrigation on the basis of antecedent climate conditions. Logistic regression equations were developed for corn, cotton, peanut, and soybean crops by using weekly irrigation water-use data from 36 metered sites in Georgia in 2009 and 2010 and turf farms in Rhode Island from 2000 to 2004. For the weeks when irrigation was predicted to take place, the irrigation water-use volume was estimated by multiplying the average metered irrigation application rate by the irrigated acreage for a given crop. The second predictive model that was developed is a crop-water-demand model that uses a daily soil water balance to estimate the water needs of a crop on a given day based on climate, soil, and plant properties. Crop-water-demand models were developed independently of reported irrigation water-use practices and relied on knowledge of plant properties that are available in the literature. Both modeling approaches require accurate accounting of irrigated area and crop type to estimate total irrigation water use. Water-use estimates from both modeling methods were compared to the metered irrigation data from Rhode Island and Georgia that were used to develop the models as well as two independent validation datasets from Georgia and Virginia that were not used in model development. Irrigation water-use estimates from the logistic regression method more closely matched mean reported irrigation rates than estimates from the crop-water-demand model when compared to the irrigation data used to develop the equations. The root mean squared errors (RMSEs) for the logistic regression estimates of mean annual irrigation ranged from 0.3 to 2.0 inches (in.) for the five crop types; RMSEs for the crop-water-demand models ranged from 1.4 to 3.9 in. However, when the models were applied and compared to the independent validation datasets from southwest Georgia from 2010, and from Virginia from 1999 to 2007, the crop-water-demand model estimates were as good as or better at predicting the mean irrigation volume than the logistic regression models for most crop types. RMSEs for logistic regression estimates of mean annual irrigation ranged from 1.0 to 7.0 in. for validation data from Georgia and from 1.8 to 4.9 in. for validation data from Virginia; RMSEs for crop-water-demand model estimates ranged from 2.1 to 5.8 in. for Georgia data and from 2.0 to 3.9 in. for Virginia data. In general, regression-based models performed better in areas that had quality daily or weekly irrigation data from which the regression equations were developed; however, the regression models were less reliable than the crop-water-demand models when applied outside the area for which they were developed. In most eastern coastal states that do not have quality irrigation data, the crop-water-demand model can be used more reliably. The development of predictive models of irrigation water use in this study was hindered by a lack of quality irrigation data. Many mid-Atlantic and New England states do not require irrigation water use to be reported. A survey of irrigation data from 14 eastern coastal states from Maine to Georgia indicated that, with the exception of the data in Georgia, irrigation data in the states that do require reporting commonly did not contain requisite ancillary information such as irrigated area or crop type, lacked precision, or were at an aggregated temporal scale making them unsuitable for use in the development of predictive models. Confidence in the reliability of either modeling method is affected by uncertainty in the reported data from which the models were developed or validated. Only through additional collection of quality data and further study can the accuracy and uncertainty of irrigation water-use estimates be improved in the humid eastern United States.
NASA Astrophysics Data System (ADS)
Lopez Bobeda, J. R.
2017-12-01
The increasing use of groundwater for irrigation of crops has exacerbated groundwater sustainability issues faced by water limited regions. Gridded, process-based crop models have the potential to help farmers and policymakers asses the effects water shortages on yield and devise new strategies for sustainable water use. Gridded crop models are typically calibrated and evaluated using county-level survey data of yield, planting dates, and maturity dates. However, little is known about the ability of these models to reproduce observed crop evapotranspiration and water use at regional scales. The aim of this work is to evaluate a gridded version of the Decision Support System for Agrotechnology Transfer (DSSAT) crop model over the continental United States. We evaluated crop seasonal evapotranspiration over 5 arc-minute grids, and irrigation water use at the county level. Evapotranspiration was assessed only for rainfed agriculture to test the model evapotranspiration equations separate from the irrigation algorithm. Model evapotranspiration was evaluated against the Atmospheric Land Exchange Inverse (ALEXI) modeling product. Using a combination of the USDA crop land data layer (CDL) and the USGS Moderate Resolution Imaging Spectroradiometer Irrigated Agriculture Dataset for the United States (MIrAD-US), we selected only grids with more than 60% of their area planted with the simulated crops (corn, cotton, and soybean), and less than 20% of their area irrigated. Irrigation water use was compared against the USGS county level irrigated agriculture water use survey data. Simulated gridded data were aggregated to county level using USDA CDL and USGS MIrAD-US. Only counties where 70% or more of the irrigated land was corn, cotton, or soybean were selected for the evaluation. Our results suggest that gridded crop models can reasonably reproduce crop evapotranspiration at the country scale (RRMSE = 10%).
Ahmad, M D; Biggs, T; Turral, H; Scott, C A
2006-01-01
Evapotranspiration (ET) from irrigated land is one of the most useful indicators to explain whether the water is used as "intended". In this study, the Surface Energy Balance Algorithm for Land (SEBAL) was used to compute actual ET from a Landsat7 image of December 29, 2000 for diverse land use in the Krishna Basin in India. SEBAL ETa varies between 0 to 4.7 mm per day over the image and was quantified for identified land use classes. Seasonal/annual comparison of ETa from different land uses requires time series images, processed by SEBAL. In this study, the Landsat-derived snapshot SEBAL ETa result was interpreted using the cropping calendar and time series analysis of MODIS imagery. The wastewater irrigated area in the basin has the highest ETa in the image, partly due to its advanced growth stage compared to groundwater-irrigated rice. Shrub and forests in the senescence phase have similar ETa to vegetable/cash crops, and ETa from grasslands is a low 0.8 mm per day after the end of the monsoon. The results indicate that wastewater irrigation of fodder and rice is sufficient to meet crop water demand but there appears to be deficit irrigation of rice using groundwater.
NASA Astrophysics Data System (ADS)
Torres-Rua, A. F.; Walker, W. R.; McKee, M.
2013-12-01
The last century has seen a large number of innovations in agriculture such as better policies for water control and management, upgraded water conveyance, irrigation, distribution, and monitoring systems, and better weather forecasting products. In spite of this, irrigation management and irrigation water deliveries by farmers/water managers is still based on factors like water share amounts, tradition, and past experience on irrigation. These factors are not necessarily related to the actual crop water use; they are followed because of the absence of related information provided in a timely manner at an affordable cost. Thus, it is necessary to develop means to deliver continuous and personalized information about crop water requirements to water users/managers at the field and irrigation system levels so managers at these levels can better quantify the required versus available water for irrigation during the irrigation season. This study presents a new decision support system (DSS) platform that addresses the absence of information on actual crop water requirements and crop performance by providing continuous updated farm-based crop water use along with other farm performance indicators such as crop yield and farm management to irrigators and water managers. This DSS exploits the periodicity of the Landsat Satellite Mission (8 to 16 days, depending on the period of interest) to provide remote monitoring at the individual field and irrigation system levels. The Landsat satellite images are converted into information about crop water use, yield performance and field management through application of state-of-the-art semi-physical and statistical algorithms that provide this information at a pixel basis that are ultimately aggregated to field and irrigation system levels. A version of the DSS has been implemented for the agricultural lands in the Lower Sevier River, Utah, and has been operational since the beginning of the 2013 irrigation season. The main goal of this DSS implementation is to provide continuous and personalized information to farmers and water managers regarding crops in fields and the irrigation delivery system throughout the irrigation season so that decisions related to agricultural water use can result in water savings while not diminishing crop yields.
Can Canals Effectively Replace Groundwater Irrigation in Over-exploited Regions in India?
NASA Astrophysics Data System (ADS)
Jain, M.; Fishman, R.; Mondal, P.; Galford, G. L.; Bhattarai, N.; Naeem, S.; DeFries, R. S.
2017-12-01
We use high-resolution data on irrigation and cropping intensity across India to empirically estimate the impacts of losing access to groundwater irrigation in regions with critically exploited aquifers. India is the largest consumer of groundwater globally and is facing severe groundwater depletion. Canals are being promoted as an alternate irrigation source, yet few studies have quantified the effects that this transition may have on agricultural production. Our results suggest that farmers will be 50% less likely to plant a winter crop, have 20% less cropped area, and have cropped areas that are increasingly sensitive to rainfall variability when switching to canal irrigation. We estimate that national winter cropped area will decrease by approximately 13% if farmers lose access to groundwater irrigation in critically over-exploited regions, and 6% if farmers in these regions switch to canal irrigation. These results suggest that groundwater and canal irrigation are not substitutable, and farmers may have to switch to less water intensive crops or improve water use efficiency to maintain current levels of production in the future.
NASA Astrophysics Data System (ADS)
Richey, A. S.; Richey, J. E.; Tan, A.; Liu, M.; Adam, J. C.; Sokolov, V.
2015-12-01
Central Asia presents a perfect case study to understand the dynamic, and often conflicting, linkages between food, energy, and water in natural systems. The destruction of the Aral Sea is a well-known environmental disaster, largely driven by increased irrigation demand on the rivers that feed the endorheic sea. Continued reliance on these rivers, the Amu Darya and Syr Darya, often place available water resources at odds between hydropower demands upstream and irrigation requirements downstream. A combination of tools is required to understand these linkages and how they may change in the future as a function of climate change and population growth. In addition, the region is geopolitically complex as the former Soviet basin states develop management strategies to sustainably manage shared resources. This complexity increases the importance of relying upon publically available information sources and tools. Preliminary work has shown potential for the Variable Infiltration Capacity (VIC) model to recreate the natural water balance in the Amu Darya and Syr Darya basins by comparing results to total terrestrial water storage changes observed from NASA's Gravity Recovery and Climate Experiment (GRACE) satellite mission. Modeled streamflow is well correlated to observed streamflow at upstream gauges prior to the large-scale expansion of irrigation and hydropower. However, current modeled results are unable to capture the human influence of water use on downstream flow. This study examines the utility of a crop simulation model, CropSyst, to represent irrigation demand and GRACE to improve modeled streamflow estimates in the Amu Darya and Syr Darya basins. Specifically we determine crop water demand with CropSyst utilizing available data on irrigation schemes and cropping patterns. We determine how this demand can be met either by surface water, modeled by VIC with a reservoir operation scheme, and/or by groundwater derived from GRACE. Finally, we assess how the inclusion of CropSyst and groundwater to model and meet irrigation demand improves modeled streamflow from VIC throughout the basins. The results of this work are integrated into a decision support platform to assist the basin states in understanding water availability and the impact of management decisions on available resources.
NASA Astrophysics Data System (ADS)
Chitu, Zenaida; Villani, Giulia; Tomei, Fausto; Minciuna, Marian; Aldea, Adrian; Dumitrescu, Alexandru; Trifu, Cristina; Neagu, Dumitru
2017-04-01
Balta Brailei is one of the largest agriculture area in the Danube floodplain, located in SE of Romania. An impressive irrigation system, that covered about 53.500 ha and transferred water from the Danube River, was carried out in the period 1960-1980. Even if the water resources for agriculture in this area cover in most of the cases the volumes required by irrigation water users, the irrigation infrastructure issues as the position of the pumping stations against the river levels hinder the use of the water during low flows periods. An efficient optimization of water allocation in agriculture could avoid periods with water deficit in the irrigation systems. Hydrological processes are essentials in describing the mass and energy exchanges in the atmosphere-plant-soil system. Furthermore, the hydrological regime in this area is very dynamic with many feedback mechanisms between the various parts of the surface and subsurface water regimes. Agricultural crops depend on capillary rise from the shallow groundwater table and irrigation. For an effective optimization of irrigation water in Balta Brailei, we propose to analyse the water balance taking into consideration the water movement into the root zone and the influence of the Danube river, irrigation channel system and the shallow aquifer by combining the soil water balance model CRITERIA and GMS hydrogeological model. CRITERIA model is used for simulating water movement into the soil, while GMS model is used for simulating the shallow groundwater level variation. The understanding of the complex feedbacks between atmosphere, crops and the various parts of the surface and subsurface water regimes in the Balta Brailei will bring more insights for predicting crop water need and water resources for irrigation and it will represent the basis for implementing Moses Platform in this specific area. Moses Platform is a GIS based system devoted to water procurement and management agencies to facilitate planning of irrigation water resources. This work is financed by the European Union's H2020 research and innovation programme under grant agreement No 642258 (Moses Project).
The implication of irrigation in climate change impact assessment: a European-wide study.
Zhao, Gang; Webber, Heidi; Hoffmann, Holger; Wolf, Joost; Siebert, Stefan; Ewert, Frank
2015-11-01
This study evaluates the impacts of projected climate change on irrigation requirements and yields of six crops (winter wheat, winter barley, rapeseed, grain maize, potato, and sugar beet) in Europe. Furthermore, the uncertainty deriving from consideration of irrigation, CO2 effects on crop growth and transpiration, and different climate change scenarios in climate change impact assessments is quantified. Net irrigation requirement (NIR) and yields of the six crops were simulated for a baseline (1982-2006) and three SRES scenarios (B1, B2 and A1B, 2040-2064) under rainfed and irrigated conditions, using a process-based crop model, SIMPLACE
Deep subsurface drip irrigation using coal-bed sodic water: part I. water and solute movement
Bern, Carleton R.; Breit, George N.; Healy, Richard W.; Zupancic, John W.; Hammack, Richard
2013-01-01
Water co-produced with coal-bed methane (CBM) in the semi-arid Powder River Basin of Wyoming and Montana commonly has relatively low salinity and high sodium adsorption ratios that can degrade soil permeability where used for irrigation. Nevertheless, a desire to derive beneficial use from the water and a need to dispose of large volumes of it have motivated the design of a deep subsurface drip irrigation (SDI) system capable of utilizing that water. Drip tubing is buried 92 cm deep and irrigates at a relatively constant rate year-round, while evapotranspiration by the alfalfa and grass crops grown is seasonal. We use field data from two sites and computer simulations of unsaturated flow to understand water and solute movements in the SDI fields. Combined irrigation and precipitation exceed potential evapotranspiration by 300-480 mm annually. Initially, excess water contributes to increased storage in the unsaturated zone, and then drainage causes cyclical rises in the water table beneath the fields. Native chloride and nitrate below 200 cm depth are leached by the drainage. Some CBM water moves upward from the drip tubing, drawn by drier conditions above. Chloride from CBM water accumulates there as root uptake removes the water. Year over year accumulations indicated by computer simulations illustrate that infiltration of precipitation water from the surface only partially leaches such accumulations away. Field data show that 7% and 27% of added chloride has accumulated above the drip tubing in an alfalfa and grass field, respectively, following 6 years of irrigation. Maximum chloride concentrations in the alfalfa field are around 45 cm depth but reach the surface in parts of the grass field, illustrating differences driven by crop physiology. Deep SDI offers a means of utilizing marginal quality irrigation waters and managing the accumulation of their associated solutes in the crop rooting zone.
NASA Astrophysics Data System (ADS)
Teixeira, A. H. de Castro; Bastiaanssen, W. G. M.; Ahmad, M. D.; Moura, M. S. B.; Bos, M. G.
2008-11-01
SummaryKnowledge on evapotranspiration is essential in quantifying water use depletion and to allocate scarce water resources to competing uses. Despite that an extensive literature describes the theoretical mechanisms of turbulent water vapour transport above and within crop canopies fewer studies have examined land surface parameters within composite landscapes of irrigated crops and semi-arid natural vegetation. Aiming to improve parameterizations of the radiation and energy balance in irrigated crops and natural vegetation, micro-climatic measurements were carried out on irrigated land (vineyards and mango orchard) and natural vegetation (caatinga) in the semi-arid zone of the São Francisco River basin (Brazil) from 2002 to 2005. The fractions of 24 h incident solar radiation available for net radiation were 46%, 55%, 51% and 53%, for wine grape, table grape, mango orchard and caatinga, respectively. Daily evaporative fractions of the net available energy used as latent heat flux ( λE) were 0.80, 0.88, 0.75 and 0.33 respectively. The daylight values of bulk surface resistances ( rs) averaged 128 s m -1, 73 s m -1, 133 s m -1 and 1940 s m -1 for wine grape, table grape, mango orchard and caatinga, respectively. Simplified parameterizations on roughness and evaporation resistances were performed. It could be concluded that net radiation can be estimated by means of a linear expression with incident global solar radiation depending on the type of vegetation. The variability of aerodynamic resistance ( ra) could be mainly explained by the friction velocity ( u ∗) which on turn depends on the surface roughness length for momentum transport ( z 0m). The experimental data showed that for sparse canopies z 0m being 9% of the mean vegetation height is a doable operational rule for the semi-arid region of São Francisco River basin. The seasonal values of rs for irrigated crops were highly correlated with water vapour pressure deficit. The availability of analytical methods to assess ra and rs makes the one-step Penman-Monteith equation suitable for the computation of actual evapotranspiration and water productivity analyses.
NASA Astrophysics Data System (ADS)
Xie, Zhenghui; Zeng, Yujin
2017-04-01
Irrigation, which constitutes 70% of the total amount of fresh water consumed by the human population, is significantly impacting the land-atmosphere fluxes. In this study, using the improved Community Land Model version 4.5 (CLM 4.5) with an active crop model, two high resolution ( 1 km) simulations investigating the effects of irrigation on Latent Heat (LH), Sensible Heat (SH) and Carbon Fluxes (or net ecosystem exchange, NEE) from land to atmosphere on the Heihe River Basin in northwestern China were conducted using a high-quality irrigation dataset compiled from 1981 to 2013. The model output and measurements from remote sensing demonstrated the capacity and viability of the developed models to reproduce ecological and hydrological processes. The results revealed the effects of irrigation on LH and SH are strongest during summer with a LH increase of 100 W/m2 and a SH decrease of 60 W/m2 over intensely irrigated areas. However, the reactions are much weaker during spring and autumn when there is much less irrigation. When the irrigation rate below 5 mm/day, the LH generally increases, whereas the SH decreases with growing irrigation rates. However, when the irrigation threshold is in excess of 5 mm/day, there is no accrued effect of irrigation on the LH and SH. Irrigation produces opposite effects to the NEE during spring and summer. During the spring, irrigation yields more discharged carbon from the land to the atmosphere, increasing the NEE value by 0.4-0.8 gC/m2/day, while the summer irrigation favors crop fixing of carbon from atmospheric CO2, decreasing the NEE value by 0.8 gC/m2/day. The repercussions of irrigation on land-atmosphere fluxes are not solely linked to the irrigation amount, and other parameters (especially the temperature) also control the effects of irrigation on LH, SH and NEE. The study indicates that how a land surface model with high spatial resolution can represent crop growing and its effects over basin scale.
NASA Astrophysics Data System (ADS)
Troy, Tara J.; Ines, Amor V. M.; Lall, Upmanu; Robertson, Andrew W.
2013-04-01
Large-scale hydrologic models, such as the Variable Infiltration Capacity (VIC) model, are used for a variety of studies, from drought monitoring to projecting the potential impact of climate change on the hydrologic cycle decades in advance. The majority of these models simulates the natural hydrological cycle and neglects the effects of human activities such as irrigation, which can result in streamflow withdrawals and increased evapotranspiration. In some parts of the world, these activities do not significantly affect the hydrologic cycle, but this is not the case in south Asia where irrigated agriculture has a large water footprint. To address this gap, we incorporate a crop growth model and irrigation model into the VIC model in order to simulate the impacts of irrigated and rainfed agriculture on the hydrologic cycle over south Asia (Indus, Ganges, and Brahmaputra basin and peninsular India). The crop growth model responds to climate signals, including temperature and water stress, to simulate the growth of maize, wheat, rice, and millet. For the primarily rainfed maize crop, the crop growth model shows good correlation with observed All-India yields (0.7) with lower correlations for the irrigated wheat and rice crops (0.4). The difference in correlation is because irrigation provides a buffer against climate conditions, so that rainfed crop growth is more tied to climate than irrigated crop growth. The irrigation water demands induce hydrologic water stress in significant parts of the region, particularly in the Indus, with the streamflow unable to meet the irrigation demands. Although rainfall can vary significantly in south Asia, we find that water scarcity is largely chronic due to the irrigation demands rather than being intermittent due to climate variability.
Optimizing preplant irrigation for maize under limited water in the high plains
USDA-ARS?s Scientific Manuscript database
Due to inadequate irrigation capacity, some farmers in the United States High Plains apply preplant irrigation to buffer the crop between irrigation events during the cropping season. The purpose of the study was to determine preplant irrigation amount and irrigation capacity combinations that optim...
A root zone modelling approach to estimating groundwater recharge from irrigated areas
NASA Astrophysics Data System (ADS)
Jiménez-Martínez, J.; Skaggs, T. H.; van Genuchten, M. Th.; Candela, L.
2009-03-01
SummaryIn irrigated semi-arid and arid regions, accurate knowledge of groundwater recharge is important for the sustainable management of scarce water resources. The Campo de Cartagena area of southeast Spain is a semi-arid region where irrigation return flow accounts for a substantial portion of recharge. In this study we estimated irrigation return flow using a root zone modelling approach in which irrigation, evapotranspiration, and soil moisture dynamics for specific crops and irrigation regimes were simulated with the HYDRUS-1D software package. The model was calibrated using field data collected in an experimental plot. Good agreement was achieved between the HYDRUS-1D simulations and field measurements made under melon and lettuce crops. The simulations indicated that water use by the crops was below potential levels despite regular irrigation. The fraction of applied water (irrigation plus precipitation) going to recharge ranged from 22% for a summer melon crop to 68% for a fall lettuce crop. In total, we estimate that irrigation of annual fruits and vegetables produces 26 hm 3 y -1 of groundwater recharge to the top unconfined aquifer. This estimate does not include important irrigated perennial crops in the region, such as artichoke and citrus. Overall, the results suggest a greater amount of irrigation return flow in the Campo de Cartagena region than was previously estimated.
Analytical steady-state solutions for water-limited cropping systems using saline irrigation water
NASA Astrophysics Data System (ADS)
Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.
2014-12-01
Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess advantages over available alternatives, including: (i) the solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.
NASA Astrophysics Data System (ADS)
Huang, G.
2016-12-01
Currently, studying crop-water response mechanism has become an important part in the development of new irrigation technology and optimal water allocation in water-scarce regions, which is of great significance to crop growth guidance, sustainable utilization of agricultural water, as well as the sustainable development of regional agriculture. Using multiple crop models(AquaCrop,SWAP,DNDC), this paper presents the results of simulating crop growth and agricultural water consumption of the winter-wheat and maize cropping system in north china plain. These areas are short of water resources, but generates about 23% of grain production for China. By analyzing the crop yields and the water consumption of the traditional flooding irrigation, the paper demonstrates quantitative evaluation of the potential amount of water use that can be reduced by using high-efficient irrigation approaches, such as drip irrigation. To maintain food supply and conserve water resources, the research concludes sustainable irrigation methods for the three provinces for sustainable utilization of agricultural water.
NASA Astrophysics Data System (ADS)
Nogueira, A. M.; Paço, T. A.; Silvestre, J. C.; Gonzalez, L. F.; Santos, F. L.; Pereira, L. S.
2012-04-01
The water footprint of a crop is the volume of water that is necessary to produce it, therefore relating crop water requirements and yield. The components of water footprint, blue, green and grey water footprints, refer to the volumes of respectively, surface and groundwater, rainfall, and water required to assimilate pollution, that are used to produce the crop yield. Determining blue and green water footprints is generally achieved using estimates of evapotranspiration obtained with a crop coefficient approach and of a water use ratio. In the present study we have used evapotranspiration measurements to estimate the water footprint of a super-intensive olive grove in southern Portugal (cv. Arbequina, drip irrigated, 1975 trees ha-1), during 2011. The crop water requirements were measured using a heat dissipation sap flow technique, to determine transpiration and using the eddy covariance method that allowed the direct measurement of evapotranspiration, applied to non-flat terrain conditions. This technique was used for a short period, from end of July till the end of August, while the sap flow measurements were performed from May to December, hence allowing the extension of the data series; for other periods estimates were used. Evapotranspiration measured directly with the eddy covariance method was in average close to 3 mm d-1 and the ratio of evapotranspiration to reference evapotranspiration approached 0.6 for the same period. Plants were under a moderate water stress, as confirmed with predawn leaf water potential measurements. The water footprint of the olive crop under study was lower than the water footprint simulations reported in literature. A possible reason relates to the density of plantation, yield and irrigation crops management. The irrigated olive grove under study had a high yield, which compensates for a high water consumption, leading to a water footprint lower than the ones of rainfed or less dense groves. Furthermore, as evapotranspiration measurements were used to calculate water footprint instead of the common procedure (using evapotranspiration estimates), this might have also introduced some differences. The potential of using remote sensing techniques for the assessment of water footprint of crops has been discussed in recent literature. It can provide estimates of actual evapotranspiration, of precipitation, of surface runoff and of irrigation needs when associated with modelling. In this study we further compare the water footprint estimates using in situ evapotranspiration measurements and water footprint estimates using remote sensing techniques. A comparison with the irrigation records for this particular olive orchard will be used to validate the approaches.
Observations of cloud and rainfall enhancement over irrigated agriculture in an arid environment
NASA Astrophysics Data System (ADS)
Garcia-Carreras, Luis; Marsham, John H.; Spracklen, Dominick V.
2017-04-01
The impact of irrigated agriculture on clouds and rainfall remains uncertain, particularly in less studied arid regions. Irrigated crops account for 20% of global cropland area, and non-renewable groundwater accounts for 20% of global irrigation water demand. Quantifying the feedbacks between agriculture and the atmosphere are therefore not only necessary to better understand the climate impacts of land-use change, but are also crucial for predicting long-term water use in water-scarce regions. Here we use high spatial-resolution satellite data to show the impact of irrigated crops in the arid environment of northern Saudi Arabia on cloud cover and rainfall patterns. Land surface temperatures over the crops are 5-10 K lower than their surroundings, linked to evapotranspiration rates of up to 20 mm/ month. Daytime cloud cover is up to 30% higher over the cropland compared to its immediate surroundings, and this enhancement is highly correlated with the seasonal variability in leaf area index. The cloud enhancement is associated with a much more rapid cloud cloud development during the morning. Afternoon rainfall is 85% higher over, and just downwind, of the cropland during the growing season, although rainfall remains very low in absolute terms. The feedback sign we find is the opposite to what has been observed in tropical and semiarid regions, where temperature gradients promote convergence and clouds on the warmer side of land-surface type discontinuities. This suggests that different processes are responsible for the land-atmosphere feedback in very dry environments, where lack of moisture may be a stronger constraint. Increased cloud and rainfall, and associated increases in diffuse radiation and reductions in temperature, can affect vegetation growth thus producing an internal feedback. These effects will therefore need to be taken into account to properly assess the impact of climate change on crop productivity and water use, as well as how global land-use change affects climate.
Measurement of surface energy balance components in dryland wheat/fallow and limited-irrigation corn
USDA-ARS?s Scientific Manuscript database
Water evaporation from soil and plant surfaces and plant transpiration comprise land surface/canopy evapotranspiration (ET), which is essential to estimate for land-atmosphere interaction and crop water use. There are no direct measurements of ET, and the most direct methods (e.g., weighing lysimet...
The Impact of Changing Snowmelt Timing on Non-Irrigated Crop Yield in Idaho
NASA Astrophysics Data System (ADS)
Murray, E. M.; Cobourn, K.; Flores, A. N.; Pierce, J. L.; Kunkel, M. L.
2013-12-01
The impacts of climate change on water resources have implications for both agricultural production and grower welfare. Many mountainous regions in the western U.S. rely on snowmelt as the dominant surface water source, and in Idaho, reconstructions of spring snowmelt timing have demonstrated a trend toward earlier, more variable snowmelt dates within the past 20 years. This earlier date and increased variability in snowmelt timing have serious implications for agriculture, but there is considerable uncertainty about how agricultural impacts vary by region, crop-type, and practices like irrigation vs. dryland farming. Establishing the relationship between snowmelt timing and agricultural yield is important for understanding how changes in large-scale climatic indices (like snowmelt date) may be associated with changes in agricultural yield. This is particularly important where local practitioner behavior is influenced by historically observed relationships between these climate indices and yield. In addition, a better understanding of the influence of changes in snowmelt on non-irrigated crop yield may be extrapolated to better understand how climate change may alter biomass production in non-managed ecosystems. To investigate the impact of snowmelt date on non-irrigated crop yield, we developed a multiple linear regression model to predict historical wheat and barley yield in several Idaho counties as a function of snowmelt date, climate variables (precipitation and growing degree-days), and spatial differences between counties. The relationship between snowmelt timing and non-irrigated crop yield at the county level is strong in many of the models, but differs in magnitude and direction for the two different crops. Results show interesting spatial patterns of variability in the correlation between snowmelt timing and crop yield. In four southern counties that border the Snake River Plain and one county bordering Oregon, non-irrigated wheat and/or barley yield are significantly lower in years with early snowmelt timing, on average (P < 0.10). In contrast, in northern Idaho, barley yield is significantly higher in years with early snowmelt timing. Overall, this statistical modeling exercise indicates that the trend toward earlier snowmelt date may positively impact non-irrigated crop yield in some regions of Idaho, while negatively impacting yield in other areas. Additional research is necessary to identify spatial controls on the variable relationship between snowmelt timing and yield. Regional variability in the response of crops to changes in snowmelt timing may indicate that external factors (e.g. higher amounts of summer rain in northern vs. southern Idaho) may play an important role in crop yield. This study indicates that targeted regional analysis is necessary to determine the influence of climate change on agriculture, as local variability can cause the same forcing to produce opposite results.
Matching soil salinization and cropping systems in communally managed irrigation schemes
NASA Astrophysics Data System (ADS)
Malota, Mphatso; Mchenga, Joshua
2018-03-01
Occurrence of soil salinization in irrigation schemes can be a good indicator to introduce high salt tolerant crops in irrigation schemes. This study assessed the level of soil salinization in a communally managed 233 ha Nkhate irrigation scheme in the Lower Shire Valley region of Malawi. Soil samples were collected within the 0-0.4 m soil depth from eight randomly selected irrigation blocks. Irrigation water samples were also collected from five randomly selected locations along the Nkhate River which supplies irrigation water to the scheme. Salinity of both the soil and the irrigation water samples was determined using an electrical conductivity (EC) meter. Analysis of the results indicated that even for very low salinity tolerant crops (ECi < 2 dS/m), the irrigation water was suitable for irrigation purposes. However, root-zone soil salinity profiles depicted that leaching of salts was not adequate and that the leaching requirement for the scheme needs to be relooked and always be adhered to during irrigation operation. The study concluded that the crop system at the scheme needs to be adjusted to match with prevailing soil and irrigation water salinity levels.
NASA Astrophysics Data System (ADS)
Liu, Lei; Luo, Yi; He, Chansheng; Lai, Jianbin; Li, Xiubin
2010-09-01
SummaryThe commonly used irrigation system in the irrigation districts (with a combined irrigation area of 3.334 × 10 6 ha) along the lower Yellow River of China is canal network. It delivers water from the Yellow River to the fields, collects surface runoff and drainage from cropland, and stores both of them for subsequent irrigation uses. This paper developed a new combined irrigation, drainage, and storage (CIDS) module for the SWAT2000 model, simulated the multiple roles of the CIDS canal system, and estimated its performance in improving water reuse in the irrigation districts under different irrigation and water diversion scenarios. The simulation results show that the annual evapotranspiration (ET) of the double-cropping winter wheat and summer maize was the highest under the full irrigation scenario (automatic irrigation), and the lowest under the no irrigation scenario. It varied between these two values when different irrigation schedules were adopted. Precipitation could only meet the water requirement of the double-cropping system by 62-96% on an annual basis; that of the winter wheat by 32-36%, summer maize by 92-123%, and cotton by 87-98% on a seasonal basis. Hence, effective irrigation management for winter wheat is critical to ensure high wheat yield in the study area. Runoff generation was closely related to precipitation and influenced by irrigation. The highest and lowest annual runoff accounted for 19% and 11% of the annual precipitation under the full irrigation and no irrigation scenarios, respectively. Nearly 70% of the annual runoff occurred during months of July and August due to the concentrated precipitation in these 2 months. The CIDS canals play an important role in delivering the diversion water from the Yellow River, intercepting the surface runoff and drainage from cropland (inflow of the CIDS canal) and recharging the shallow aquifer for later use. Roughly 14-26% of the simulated total flow in the CIDS canal system recharged shallow aquifer through canal seepage. The water flowing out of the canal system accounted for approximately 32% of the water in the CIDS canals. The storage capacity of the CIDS canals is negatively correlated to the precipitation. In years with abundant precipitation, the volume of the surface runoff and drainage from the cropland may surpass the storage capacities of the CIDS canals, while in years with less precipitation, partial storage capacity of the CIDS canal may be occupied by the diversion water from the Yellow River. Proper maintenance of the storage capacity of the CIDS has the potential in improving the efficiency of reusing the surface runoff and field drainage for irrigation practices to mitigate the increasing water shortage along the lower Yellow River.
NASA Astrophysics Data System (ADS)
Kaneko, D.
2017-12-01
Climate change initiates abnormal meteorological disasters. Drought causes climate instability, thus producing poor harvests because of low rates of photosynthesis and sterile pollination. This research evaluates drought indices regarding precipitation and includes this data in global geophysical crop models that concern with evaporation, stomata opening, advection-effects from sea surface temperature anomalies, photosynthesis, carbon partitioning, crop yields, and crop production. Standard precipitation index (SPI) is a useful tool because of related variable not used in the stomata model. However, SPI is not an adequate tool for drought in irrigated fields. Contrary to expectations, the global comparisons of spatial characteristics between stomata opening/evapotranspiration and SPI for monitoring continental crop extremes produced serious defects and obvious differences between evapotranspiration and the small stomata-opening phenomena. The reason for this is that SPI does not include surface air temperature in its analysis. The Penman equation (Epen) describes potential evaporation better than SPI for recent hot droughts caused by climate change. However, the distribution of precipitation is a necessary condition for crop monitoring because it affirms the trend of the dry results computed by crop models. Consequently, the author uses global precipitation data observed by microwave passive sensors on TRMM and GCOM-W satellites. This remote sensing data conveniently supplies spatial distributions of global and seasonal precipitation. The author has designed a model to measure the effects of drought on crop yield and the degree of stomata closure related to the photosynthesis rate. To determine yield effects, the drought injury function is defined by integrating stomata closure during the two seasons from flowering to pollination. The stomata, defined by ratio between Epen and Eac, reflect the effects of drought and irrigation. Stomata-closure model includes the factors of soil moisture or irrigation effects inside the actual evapotranspiration computed using a complimentary model. The evaluation of precipitation indices provides necessary but not sufficient conditions for drought. They supply reference information for the trend/accuracy of an injury response function.
NASA Astrophysics Data System (ADS)
Muraleedharan, B. V.; Kathirvel, K.; Narasimhan, B.; Nallasamy, N. D.
2014-12-01
Soil Water Assessment Tool (SWAT) is a basin scale, distributed hydrological model commonly used to predict the effect of management decisions on the hydrologic response of watersheds. Hydrologic response is decided by the various components of water balance. In the case of watersheds located in south India as well as in several other tropical countries around the world, paddy is one of the dominant crop controlling the hydrologic response of a watershed. Hence, the suitability of SWAT in replicating the hydrology of paddy fields needs to be verified. Rice paddy fields are subjected to flooding method of irrigation, while the irrigation subroutines in SWAT are developed to simulate crops grown under non flooding conditions. Moreover irrigation is represented well in field scale models, while it is poorly represented within watershed models like SWAT. Reliable simulation of flooding method of irrigation and hydrology of the fields will assist in effective water resources management of rice paddy fields which are one of the major consumers of surface and ground water resources. The current study attempts to modify the irrigation subroutine in SWAT so as to simulate flooded irrigation condition. A field water balance study was conducted on representative fields located within Gadana, a subbasin located in Tamil Nadu (southern part of India) and dominated by rice paddy based irrigation systems. The water balance of irrigated paddy fields simulated with SWAT was compared with the water balance derived by rice paddy based crop growth model named ORYZA. The variation in water levels along with the soil moisture variation predicted by SWAT was evaluated with respect to the estimates derived from ORYZA. The water levels were further validated with field based water balance measurements taken on a daily scale. It was observed that the modified irrigation subroutine was able to simulate irrigation of rice paddy within SWAT in a realistic way compared to the existing method.
NASA Astrophysics Data System (ADS)
Dale, A. L.; Boehlert, B.; Reisenauer, M.; Strzepek, K. M.; Solomon, S.
2017-12-01
Climate change poses substantial risks to African agriculture. These risks are exacerbated by concurrent risks to water resources, with water demand for irrigation comprising 80 to 90% of water withdrawals across the continent. Process-based crop growth models are able to estimate both crop demand for irrigation water and crop yields, and are therefore well-suited to analyses of climate change impacts at the food-water nexus. Unfortunately, impact assessments based on these models generally focus on either yields or water demand, rarely both. For this work, we coupled a crop model to a water resource management model in order to predict national trends in the impact of climate change on crop production, irrigation water demand, and the availability of water for irrigation across Africa. The crop model FAO AquaCrop-OS was run at 2ox2o resolution for 17 different climate futures from the CMIP5 archive, nine for Representative Concentration Pathway (RCP) 4.5 and eight for RCP8.5. Percent changes in annual rainfed and irrigated crop production and temporal shifts in monthly irrigation water demand were estimated for the years 2030, 2050, 2070, and 2090 for maize, sorghum, rice, wheat, cotton, sugarcane, fruits & vegetables, roots & tubers, and legumes & soybeans. AquaCrop was then coupled to a water management model (WEAP) in order to project changes in the ability of seven major river basins (the Congo, Niger, Nile, Senegal, Upper Orange, Volta, and Zambezi) to meet irrigation water demand out to 2050 in both average and dry years in the face of both climate change and irrigation expansion. Spatial and temporal trends were identified and interpreted through the lens of potential risk management strategies. Uncertainty in model estimates is reported and discussed.
Automation of irrigation systems to control irrigation applications and crop water use efficiency
USDA-ARS?s Scientific Manuscript database
Agricultural irrigation management to slow water withdrawals from non-replenishing quality water resources is a global endeavor and vital to sustaining irrigated agriculture and dependent rural economies. Research in site-specific irrigation management has shown that water use efficiency, and crop p...
NASA Astrophysics Data System (ADS)
Bhattarai, N.; Jain, M.
2016-12-01
Expected changes in temperature and precipitation patterns in the rice-wheat belt of Northern India have implications for balancing crop water demand and available water resources. Because the impacts of water scarcity and reduced crop production are realized at a local scale, water-saving interventions are most effective when implemented locally. However, a paucity of fine-scale studies on the relationship between variations in climate and crop water demand has limited our ability to effectively implement such interventions. In an effort to better understand the responses of irrigated crops to changing climate in Northern India at finer-scales, we propose a remote sensing based semi-empirical approach. First, we employ a multi-model surface energy balance (SEB) approach to map seasonal evapotranspiration (ET)/water use (1995-2015) at 30 to 100 m resolution from space and investigate how seasonal and inter-annual variations in temperature and precipitation are associated with regional surface-energy budgets. Second, using remote estimates of ET and other biophysical variables, such as vegetation indices, land surface temperature, and albedo, we will explain the possible relationships between climate change and seasonal water demands of crops. Our estimates of high/moderate resolution (30 to 100 m) seasonal ET maps can make clear distinctions between impacts of climate variations on crop water demand at field, plot, and regional scales in Northern India. Finally, by improving our ability to identify targeted area for water-saving interventions, this study supports agricultural resiliency of Northern India in the face of climate change.
Wastewater retreatment and reuse system for agricultural irrigation in rural villages.
Kim, Minyoung; Lee, Hyejin; Kim, Minkyeong; Kang, Donghyeon; Kim, Dongeok; Kim, YoungJin; Lee, Sangbong
2014-01-01
Climate changes and continuous population growth increase water demands that will not be met by traditional water resources, like surface and ground water. To handle increased water demand, treated municipal wastewater is offered to farmers for agricultural irrigation. This study aimed to enhance the effluent quality from worn-out sewage treatment facilities in rural villages, retreat effluent to meet water quality criteria for irrigation, and assess any health-related and environmental impacts from using retreated wastewater irrigation on crops and in soil. We developed the compact wastewater retreatment and reuse system (WRRS), equipped with filters, ultraviolet light, and bubble elements. A pilot greenhouse experiment was conducted to evaluate lettuce growth patterns and quantify the heavy metal concentration and pathogenic microorganisms on lettuce and in soil after irrigating with tap water, treated wastewater, and WRRS retreated wastewater. The purification performance of each WRRS component was also assessed. The study findings revealed that existing worn-out sewage treatment facilities in rural villages could meet the water quality criteria for treated effluent and also reuse retreated wastewater for crop growth and other miscellaneous agricultural purposes.
NASA Astrophysics Data System (ADS)
Autovino, Dario; Negm, Amro; Rallo, Giovanni; Provenzano, Giuseppe
2016-04-01
In Mediterranean countries characterized by limited water resources for agricultural and societal sectors, irrigation management plays a major role to improve water use efficiency at farm scale, mainly where irrigation systems are correctly designed to guarantee a suitable application efficiency and the uniform water distribution throughout the field. In the last two decades, physically-based agro-hydrological models have been developed to simulate mass and energy exchange processes in the soil-plant-atmosphere (SPA) system. Mechanistic models like HYDRUS 2D/3D (Šimunek et al., 2011) have been proposed to simulate all the components of water balance, including actual crop transpiration fluxes estimated according to a soil potential-dependent sink term. Even though the suitability of these models to simulate the temporal dynamics of soil and crop water status has been reported in the literature for different horticultural crops, a few researches have been considering arboreal crops where the higher gradients of root water uptake are the combination between the localized irrigation supply and the three dimensional root system distribution. The main objective of the paper was to assess the performance of HYDRUS-2D model to evaluate soil water contents and transpiration fluxes of an olive orchard irrigated with two different water distribution systems. Experiments were carried out in Castelvetrano (Sicily) during irrigation seasons 2011 and 2012, in a commercial farm specialized in the production of table olives (Olea europaea L., var. Nocellara del Belice), representing the typical variety of the surrounding area. During the first season, irrigation water was provided by a single lateral placed along the plant row with four emitters per plant (ordinary irrigation), whereas during the second season a grid of emitters laid on the soil was installed in order to irrigate the whole soil surface around the selected trees. The model performance was assessed based on the comparison between measured and simulated soil water content and actual transpiration fluxes, under the hypothesis to neglect the contribute of the tree capacitance. Moreover, two different crop water stress functions and in particular the linear model proposed by Feddes et al. (1978) and the S-shape model suggested by van Genuchten et al. (1987), were considered. The result of the study evidenced that for the investigated crop and under the examined conditions, HYDRUS-2D model reproduces fairly well the dynamic of soil water contents at different distances from the emitters (RMSE<0.09 cm3 cm-3) and actual crop transpiration fluxes (RMSE<0.11 mm d-1), whose estimations can be slightly improved by assuming a S-shape crop water stress function. Key-words: Olive tree, HYDRUS-2D, Soil water content, Actual transpiration fluxes
Evaporation from irrigated crops: Its measurement, modeling and estimation from remotely sensed data
NASA Astrophysics Data System (ADS)
Garatuza-Payan, Jaime
The research described in this dissertation is predicated on the hypothesis that remotely sensed information from climatological satellites can be used to estimate the actual evapotranspiration from agricultural crops to improve irrigation scheduling and water use efficiency. The goal of the enabling research program described here was to facilitate and demonstrate the potential use of satellite data for the rapid and routine estimation of water use by irrigated crops in the Yaqui Valley irrigation scheme, an extensive irrigated area in Sonora, Mexico. The approach taken was first, to measure and model the evapotranspiration and crop factors for wheat and cotton, the most common irrigated crops in the Yaqui Valley scheme. Second, to develop and test a high-resolution (4 km x 4 km) method for determining cloud cover and solar radiation from GOES satellite data. Then third, to demonstrate the application of satellite data to calculate the actual evaporation for sample crops in the Yaqui Valley scheme by combining estimates of potential rate with relevant crop factors and information on crop management. Results show that it is feasible to provide routine estimates of evaporation for the most common crops in the Yaqui Valley irrigation scheme from satellite data. Accordingly, a system to provide such estimates has been established and the Water Users Association, the entity responsible for water distribution in Yaqui Valley, can now use them to decide whether specific fields need irrigation. A Web site (teka-pucem.itson.mx) is also being created which will allow individual farmers to have direct access to the evaporation estimates via the Internet.
Does deficit irrigation of field crops increase water use efficiency
USDA-ARS?s Scientific Manuscript database
Deficit irrigation is often proposed as a method to stretch limited irrigation water supply and increase water use efficiency. A field study of field crops in the high plains shows that water use efficiency, in terms of irrigation water applied, often increases with deficit irrigation. However, in t...
NASA Astrophysics Data System (ADS)
Smilovic, M.; Gleeson, T. P.; Adamowski, J. F.; Langhorn, C.; Kienzle, S. W.
2016-12-01
Supplemental irrigation is the practice of supporting precipitation-fed agriculture with limited irrigation. Precipitation-fed agriculture dominates the agricultural landscape, but is vulnerable to intraseasonal and interannual variability in precipitation and climate. The interplay between food security, water resources, ecosystem health, energy, and livelihoods necessitates evaluating and integrating initiatives that increase agricultural production while reducing demands on water resources. Supplemental irrigation is the practice of minimally irrigating in an effort to stabilize and increase agricultural production, as well as increase water productivity - the amount of crop produced per unit of water. The potential of supplemental irrigation to support both water and food security has yet to be evaluated at regional and global scales. We evaluate whether supplemental irrigation could stabilize and increase agricultural production of wheat by determining locally-calibrated water use-crop yield relationships, known as crop-water production functions. Crop-water production functions are functions of seasonal water use and crop yield, and previous efforts have largely ignored the effects of the temporal distribution of water use throughout the growing season. We significantly improve upon these efforts and provide an opportunity to evaluate supplemental irrigation that appropriately acknowledges the effects of irrigation scheduling. Integrating agroclimatic and crop data with the crop-water model Aquacrop, we determine the increases in wheat production achieved by maximizing water productivity, sharing limited water between different years, and other irrigation scenarios. The methodology presented and evaluation of supplemental irrigation provides water mangers, policy makers, governments, and non-governmental organizations the tools to appropriately understand and determine the potential of this initiative to support precipitation-fed agriculture.
Crop water productivity and irrigation management
USDA-ARS?s Scientific Manuscript database
Modern irrigation systems offer large increases in crop water productivity compared with rainfed or gravity irrigation, but require different management approaches to achieve this. Flood, sprinkler, low-energy precision application, LEPA, and subsurface drip irrigation methods vary widely in water a...
Summary of reported agriculture and irrigation water use in Monroe County, Arkansas, 1991
Holland, T.W.; Manning, C.A.; Stafford, K.L.
1993-01-01
This report summarizes the 1991 water-use reporting through the Conservation District Office in Monroe County, Arkansas. The number of withdrawal registrations for Monroe County was 1,886 (1,677 groundwater and 209 surface water). Water withdrawals reported during the registration process total 8.87 Mgal/d (5.75 Mgal/d groundwater and 3.12 Mgal/d surface water) for agriculture and 210.61 Mgal/d (190.99 Mgal/d groundwater and 19.62 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 127,670 acres of land to irrigate rice, sorghum, soybeans, milo, cash grains, cotton, hay, and unknown crops, as well as for agricultural uses of animal aquaculture, minnows, and ducks. {descriptors: *Water use, *Arkansas, *Monroe County, Selective withdrawal, Groundwater, Surface water
NASA Astrophysics Data System (ADS)
Thekkemeppilly Sivakumar, I.; Steenhuis, T. S.; Walter, M. F.; Ghosh, S.; Salvi, K. A.
2015-12-01
Intensified groundwater irrigation is a major factor that contributes to water table decline. This phenomenon has been documented in many parts of the world. This study investigates trends in water table in response to agriculture intensification to meet increasing food demand, water management practices and climate change. A shallow-aquifer model based on the extended Thornthwaite-Mather procedure is used to predict groundwater levels in response to precipitation, evapotranspiration, and groundwater pumping for irrigation. Krishna district in the state of Andhra Pradesh in southern India which has a sub-humid, monsoon climate and Calicut district of Kerala state with a wet tropical monsoon climate have been chosen as sites for this study. The effect of increasing food demand by a growing population is investigated by increasing the number of crops per year from one to three. We consider three climate scenarios and two water management practices in this study. The three climate scenarios are the ones those envisaged by the Intergovernmental Panel for Climate Change (IPCC). The two water management practices considered are the traditional flooded agriculture and the system of rice intensification method which does not use total flooding. The results show that single crop agriculture in Krishna district is sustainable for all climate scenarios and water management practices with a maximum depth to water table around 6 - 7 m at the end of dry season and the water table recovers to the surface most of the time. Increasing crop production with two or three crops per year with groundwater irrigation is unsustainable with the water table levels dropping potentially to 200 - 1000 m at the end of 21st century. We found that climate change and better irrigation water management practices affected ground water levels only minimally compared to the growing more than one crop per year. Our study leads to the conclusion that ground water irrigated rice can only be sustainable when crop evaporation is less then precipitation and in order to meet increasing food demands the rice yield per unit water should be improved.
Planetary opportunities in crop water management: Potential to outweigh cropland expansion
NASA Astrophysics Data System (ADS)
Jägermeyr, Jonas; Gerten, Dieter; Lucht, Wolfgang; Heinke, Jens
2014-05-01
Global available land and water resources probably cannot feed projected future human populations under current productivity levels. Moreover, the planetary boundaries of both land use change and water consumption are being approached rapidly, and at the same time competition between food production, bioenergy plantations and biodiversity conservation is increasing. Global cropland is expected to expand to meet future demands, while considerable yield gaps remain in many world regions. Yield increases in Sub-Saharan Africa, for example, are currently mainly based on expansion of arable land into currently non-agricultural areas - while small-scale irrigation and water conservancy methods are considered very promising to boost yields there. In the here presented modeling study we investigate, at global scale, to what degree different on-farm options to better manage green and blue water might contribute to a global crop yield increase under conditions of current climate and projected future climate change. We consider methods aiming for a maximization of crops' water use efficiency and an optimal use of available on-farm water (precipitation): reducing unproductive soil evaporation (vapor shift, VS), collecting surface runoff after rain events to mitigate subsequent dry-spells (rain-water harvesting, RWH), increasing irrigation efficiency, and expanding irrigated area into rain-fed cropland (based on water savings from higher efficiencies). Global yield simulations based on hypothetical scenarios of these management opportunities are performed with the LPJmL ecohydrological modeling framework driven by reanalysis data and GCM ensemble simulations. We consider a range of about 20 climate change projections to cover respective uncertainties, and we analyze the effects of increasing CO2 concentration on the crops and their water demand. Crops are represented in a process-based and dynamic way by 12 crop functional types, each for rain-fed and irrigated areas, with prescribed annual fractions of cropland per 0.5° x 0.5° grid cell. We recalculate from the yield increase how much cropland expansion can be avoided in 30-yr averages. Our results show that the studied affordable low-tech solutions for small-scale farmers on water-limited croplands can have a considerable effect on yields at the global scale. A simulated global ~15% yield increase from a low-intensity water management scenario (25% of runoff used for RWH, 25% of soil evaporation avoided to achieve VS, slight irrigation efficiency improvement) could outweigh, i.e. possibly avoid, an estimated 120 Mha of cropland expansion under current climatic conditions. A (rather theoretical) maximum-intensity water management scenario (85% VS, 85% RWH, surface irrigation replaced by sprinkler systems) shows the potential to increase global yields by more than 35% without expansion or withdrawing additional irrigation water. Climate change will have adverse effects on crop yields in many regions, but as we sow such adaptation opportunities have the potential to mitigate or compensate these impacts in many countries. Overall, proper water management (sustainably maximizing on-farm water use efficiency) can substantially increase global crop yields and at the same time relax rates of land cover conversion.
NASA Astrophysics Data System (ADS)
Murugappan, A.; Manoharan, A.; Senthilkumar, G.; Krishnamurthy, J.
2017-07-01
Irrigated farming depends on an ample supply of water compatible quality. Presently, a lot of irrigation projects have to depend on inferior quality and not so enviable sources of water supply. In order to prevent troubles during usage of such water supplies of poor quality, there must be meticulous preparation to ensure that the water available with such quality characteristics is put to best use. The effect of water quality upon soil and crops must be better understood in choosing fitting options to manage with impending water quality associated troubles that might decrease soil and crop productivity under existing circumstances of water use. Two tanks (small sized reservoirs) namely, Walajah Tank and Perumal Tank in Cuddalore District, used for irrigation, receive mine drainage water pumped out continuously from the open cast lignite mines of the NLC India Limited, Neyveli, Tamilnadu State. This water has been used by the farmers in the irrigated commands of both Walajah Tank and Perumal Tank for more than three decades. Recently, the beneficiaries had raised fears on the quality of mine drainage waters they had been using for raising crops in the commands of both the tanks. They opined that the coal dust laden mine water used for irrigation had affected the crop yields. This incited us to take up a study to (i) assess the status of quality of surface waters released from the two tanks for irrigation in the respective command areas and (ii) assess the likely impacts of quality of water on soil and on growth and productivity of crops cultivated in the command areas. Further to the technical evaluation of the impacts, a structured questionnaire survey was also conducted among the farmers and the common public in the study area. The findings of the survey confirmed with the outcome of the technical assessment in that the mine drainage had a poor impact in the cultivable command area of Walajah tank system while such impacts were less significant in most parts of the command area of Perumal tank system.
NASA Astrophysics Data System (ADS)
Garrigues, S.; Olioso, A.; Carrer, D.; Decharme, B.; Calvet, J.-C.; Martin, E.; Moulin, S.; Marloie, O.
2015-10-01
Generic land surface models are generally driven by large-scale data sets to describe the climate, the soil properties, the vegetation dynamic and the cropland management (irrigation). This paper investigates the uncertainties in these drivers and their impacts on the evapotranspiration (ET) simulated from the Interactions between Soil, Biosphere, and Atmosphere (ISBA-A-gs) land surface model over a 12-year Mediterranean crop succession. We evaluate the forcing data sets used in the standard implementation of ISBA over France where the model is driven by the SAFRAN (Système d'Analyse Fournissant des Renseignements Adaptés à la Nivologie) high spatial resolution atmospheric reanalysis, the leaf area index (LAI) time courses derived from the ECOCLIMAP-II land surface parameter database and the soil texture derived from the French soil database. For climate, we focus on the radiations and rainfall variables and we test additional data sets which include the ERA-Interim (ERA-I) low spatial resolution reanalysis, the Global Precipitation Climatology Centre data set (GPCC) and the MeteoSat Second Generation (MSG) satellite estimate of downwelling shortwave radiations. The evaluation of the drivers indicates very low bias in daily downwelling shortwave radiation for ERA-I (2.5 W m-2) compared to the negative biases found for SAFRAN (-10 W m-2) and the MSG satellite (-12 W m-2). Both SAFRAN and ERA-I underestimate downwelling longwave radiations by -12 and -16 W m-2, respectively. The SAFRAN and ERA-I/GPCC rainfall are slightly biased at daily and longer timescales (1 and 0.5 % of the mean rainfall measurement). The SAFRAN rainfall is more precise than the ERA-I/GPCC estimate which shows larger inter-annual variability in yearly rainfall error (up to 100 mm). The ECOCLIMAP-II LAI climatology does not properly resolve Mediterranean crop phenology and underestimates the bare soil period which leads to an overall overestimation of LAI over the crop succession. The simulation of irrigation by the model provides an accurate irrigation amount over the crop cycle but the timing of irrigation occurrences is frequently unrealistic. Errors in the soil hydrodynamic parameters and the lack of irrigation in the simulation have the largest influence on ET compared to uncertainties in the large-scale climate reanalysis and the LAI climatology. Among climate variables, the errors in yearly ET are mainly related to the errors in yearly rainfall. The underestimation of the available water capacity and the soil hydraulic diffusivity induce a large underestimation of ET over 12 years. The underestimation of radiations by the reanalyses and the absence of irrigation in the simulation lead to the underestimation of ET while the overall overestimation of LAI by the ECOCLIMAP-II climatology induces an overestimation of ET over 12 years. This work shows that the key challenges to monitor the water balance of cropland at regional scale concern the representation of the spatial distribution of the soil hydrodynamic parameters, the variability of the irrigation practices, the seasonal and inter-annual dynamics of vegetation and the spatiotemporal heterogeneity of rainfall.
Summary of reported agriculture and irrigation water use in Prairie County, Arkansas, 1991
Holland, T.W.; Manning, C.A.; Stafford, K.L.
1993-01-01
This report summarizes the 1991 water-use reporting through the Conservation District Office in Prairie County, Arkansas. The number of withdrawal registrations for Prairie County was 2,187 (1,786 groundwater and 401 surface water). Water with- drawals reported during the registration process total 26.93 Mgal/d (26.84 Mgal/d groundwater and 0.09 Mgal/d surface water) for agriculture and 191.08 Mgal/d (138.79 Mgal/d groundwater and 52.29 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 144,956 acres of land to irrigate rice, corn, soybeans, milo, cash grains, unknown crop, cotton hay, berries, and fruit trees as well as for the agricultural uses of animal aquaculture, minnows, timber, and ducks.
A 12-Month Study of Food Crops Contaminated by Heavy Metals, Lusaka, Zambia
NASA Astrophysics Data System (ADS)
Holden, J. A.; Malamud, B. D.; Chishala, B. H.; Kapungwe, E.; Volk, J.; Harpp, K. S.
2009-04-01
We investigate heavy-metal contamination of irrigation water used for urban agriculture and subsequent contamination of food crops in Chunga, NW Lusaka, the capital of Zambia. Inhabitants of the Chunga area rely on urban agriculture as both a major source of income and food. From August 2004 to July 2005, monthly samples of irrigation water used and edible portions of food crops were taken from a farmer's plot at Chunga. The food crops (cabbage, Chinese cabbage, pumpkin leaves, rape, sweet potato leaves and tomatoes) are grown using irrigation throughout the year. Irrigation water samples and digested food crop samples were analysed using ICP-MS at the Department of Geology, Colgate University, USA for Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Ba, Hg, Tl, Pb, and U. We find heavy-metal concentrations present in both irrigation water and food crop samples. Zambian sample concentrations were compared to Zambian and international legislative and guideline limits for concentrations of heavy metals in industrial effluent, heavy metals in irrigation water and heavy metals in foods. In irrigation water samples recommended national and/or international legislative limits for Al, Cr, Mn, Fe, Cu, Hg, Pb and U were exceeded. Limits for Hg were exceeded by up to 130 times. There were heavy-metal concentrations above recommended limits in food crops for Cr, Fe, Ni, Cu, Zn, Cd, Hg and Pb throughout the different food crops grown and throughout the year. In all 14 samples recommended limits for Cr, Fe and Hg were exceeded. Zambian legislated limits for food crops were exceeded by up to 16 times for Pb and 58 times for Hg. The results of this study show that heavy metal contamination is present in irrigation water used and food crops grown in urban agriculture in Chunga, Lusaka, Zambia. Recommended maximum limits for heavy metals in irrigation water and food are exceeded in some samples indicating there may be a risk to health.
Geographic information system applied to the estimation of the plant water status
NASA Astrophysics Data System (ADS)
Castillo, Cristina; de la Rosa, Jose Mª; Temnani, Abdel; Pérez-Pastor, Alejandro
2017-04-01
The importance of Geographic Information Systems (GIS) at handling managing geospatial data is demonstrated in a large number of scientific and professionals disciplines that have an impact on the territory. Thus, in agriculture, it is a transversal tool that includes the recopilation of: (i) geographic information: soil-plant geolocated sensors in experimental fields, water and fertilizers consumption for each irrigation sector, energy consumption and digital surface models (ii) representation and analysis: obtaining temperature maps, aspect models, solar radiation, run-off and salinity, as well as hardware, software and the people who compose it, results in the optimization of resources (goods, energy and workforce) what it makes the farm more efficient and more beneficial for the environment. In addition, in this project, the use of new technologies, such as satellite imagery or drones with multispectral cameras, allow to obtain other parameters that are not observed with the naked eye, like the state of the crop in spectroradiometric terms (remote sensing), stressed crops through indexes like NDVI, that may lead to take decisions like: (i) irrigation variations (ii) early detection of fillings in droppers (iii) affected areas for a pest, helping to distribute the workforce efficiently (pesticide use in an optimal way). The main objective of GIS use in this project is to establish direct relationships between parameters taken from the soil and plant with image processing in four different crops, orange, peach, apricot trees and table grape. In this way, the leaf area index (LAI) can be calculated, assessing how different irrigation management affects: i) Control (CTL), irrigated to ensure non-limiting water conditions (120% of crop evapotranspiration) and ii) Regulated deficit irrigation (RDI) irrigated as CTL during critical periods and decreasing irrigation in non-critical periods. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).
USDA-ARS?s Scientific Manuscript database
An increase in abnormal climate change patterns and unsustainable irrigation in uplands cause drought and affect agricultural water security, crop productivity, and price fluctuations. In this study, we developed a soil moisture model to project irrigation requirements (IR) for upland crops under cl...
NASA Astrophysics Data System (ADS)
Multsch, S.; Exbrayat, J.-F.; Kirby, M.; Viney, N. R.; Frede, H.-G.; Breuer, L.
2015-04-01
Irrigation agriculture plays an increasingly important role in food supply. Many evapotranspiration models are used today to estimate the water demand for irrigation. They consider different stages of crop growth by empirical crop coefficients to adapt evapotranspiration throughout the vegetation period. We investigate the importance of the model structural versus model parametric uncertainty for irrigation simulations by considering six evapotranspiration models and five crop coefficient sets to estimate irrigation water requirements for growing wheat in the Murray-Darling Basin, Australia. The study is carried out using the spatial decision support system SPARE:WATER. We find that structural model uncertainty among reference ET is far more important than model parametric uncertainty introduced by crop coefficients. These crop coefficients are used to estimate irrigation water requirement following the single crop coefficient approach. Using the reliability ensemble averaging (REA) technique, we are able to reduce the overall predictive model uncertainty by more than 10%. The exceedance probability curve of irrigation water requirements shows that a certain threshold, e.g. an irrigation water limit due to water right of 400 mm, would be less frequently exceeded in case of the REA ensemble average (45%) in comparison to the equally weighted ensemble average (66%). We conclude that multi-model ensemble predictions and sophisticated model averaging techniques are helpful in predicting irrigation demand and provide relevant information for decision making.
NASA Astrophysics Data System (ADS)
Barik, M. G.; Rushi, B. R.; Malek, K.; Rajagopalan, K.; Hall, S.; Kruger, C. E.; Brady, M.; Stockle, C.; Adam, J. C.
2016-12-01
Agriculture contributes about 12% in Washington State's economy. Water diverted from the Columbia River Basin (CRB) is the major source of irrigation water in this region. Although agriculture accounts for 80% of this state's total water withdrawal, this sector is the first to be curtailed (i.e., irrigators do not receive their full water right allocation) while there is a water shortage. This snow dominated region is already threatened by climate change. A robust regional-scale analysis of water supply, demand, unmet crop water requirements and associated impacts is critical to develop sustainable water resources plans under climate change. This study uses a dynamically-coupled hydrologic and cropping systems model, VIC-CropSyst, a reservoir management model, ColSim, and a water curtailment model to simulate changes in surface water irrigation demand projecting 30 years in the future in response to various climate, management and economic scenarios. Five downscaled climate scenarios for each of the IPCC's Representative Concentration Pathway 4.5 (rcp4.5) and 8.5 (rcp8.5) are selected in a way that they capture the projected spread of temperature and precipitation changes for the area. Results show an increase in total water availability across the CRB. Water availability is predicted to shift earlier in the season due to warming-induced snowpack reductions. Agricultural water demand is projected to decrease by approximately 5.0% (±0.7%) and 6.9% (±0.7%) respectively across the entire CRB and the Washington portion of the CRB by 2035. Irrigation demand is expected to shift earlier in the season along with water availability. This shift in demand may cause higher amount of early season irrigation water curtailment in some highly managed watersheds of the CRB in Washington State. This reduction and shift in demand is due to a warmer climate and an elevated atmospheric CO2 level which are leading to a shorter but early starting growing season. This study does not consider any expansion of irrigated crop lands for future, or any adaption measures such as double cropping, switching to slow maturing crop varieties. Curtailment increasing in the early season and declining in the late season may require adjustments to reservoir operations unless proper adaptive measures are taken.
Mapping irrigated areas of Ghana using fusion of 30 m and 250 m resolution remote-sensing data
Gumma, M.K.; Thenkabail, P.S.; Hideto, F.; Nelson, A.; Dheeravath, V.; Busia, D.; Rala, A.
2011-01-01
Maps of irrigated areas are essential for Ghana's agricultural development. The goal of this research was to map irrigated agricultural areas and explain methods and protocols using remote sensing. Landsat Enhanced Thematic Mapper (ETM+) data and time-series Moderate Resolution Imaging Spectroradiometer (MODIS) data were used to map irrigated agricultural areas as well as other land use/land cover (LULC) classes, for Ghana. Temporal variations in the normalized difference vegetation index (NDVI) pattern obtained in the LULC class were used to identify irrigated and non-irrigated areas. First, the temporal variations in NDVI pattern were found to be more consistent in long-duration irrigated crops than with short-duration rainfed crops due to more assured water supply for irrigated areas. Second, surface water availability for irrigated areas is dependent on shallow dug-wells (on river banks) and dug-outs (in river bottoms) that affect the timing of crop sowing and growth stages, which was in turn reflected in the seasonal NDVI pattern. A decision tree approach using Landsat 30 m one time data fusion with MODIS 250 m time-series data was adopted to classify, group, and label classes. Finally, classes were tested and verified using ground truth data and national statistics. Fuzzy classification accuracy assessment for the irrigated classes varied between 67 and 93%. An irrigated area derived from remote sensing (32,421 ha) was 20-57% higher than irrigated areas reported by Ghana's Irrigation Development Authority (GIDA). This was because of the uncertainties involved in factors such as: (a) absence of shallow irrigated area statistics in GIDA statistics, (b) non-clarity in the irrigated areas in its use, under-development, and potential for development in GIDA statistics, (c) errors of omissions and commissions in the remote sensing approach, and (d) comparison involving widely varying data types, methods, and approaches used in determining irrigated area statistics using GIDA and remote sensing. Extensive field campaigns to help in better classification and validation of irrigated areas using high (30 m ) to very high (<5 m) resolution remote sensing data that are fused with multi temporal data like MODIS are the way forward. This is especially true in accounting for small yet contiguous patches of irrigated areas from dug-wells and dug-outs. ?? 2011 by the authors.
Droplet Kinetic Energy from Center-Pivot Sprinklers
USDA-ARS?s Scientific Manuscript database
The kinetic energy of discrete water drops impacting a bare soil surface is generally observed to lead to a drastic reduction in water infiltration rate due to soil surface seal formation. Under center-pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy developmen...
Jenkins, Michael B; Endale, Dinku M; Schomberg, Harry H; Hartel, Peter G; Cabrera, Miguel L
2009-06-01
Thirteen million [corrected] metric tons of poultry litter are produced annually by poultry producers in the U.S. Poultry litter contains the sex hormones estradiol and testosterone, endocrine disruptors that have been detected in surface waters. The objective of this study was to evaluate the potential impact of poultry litter applications on estradiol and testosterone concentrations in subsurface drainage and surface runoff in irrigated crop land under no-till and conventional-till management. We conducted an irrigation study in fall of 2001 and spring of 2002. Four treatments, no-till plus poultry litter, conventional-till plus poultry litter, no-till plus conventional fertilizer, and conventional-till plus conventional fertilizer, were evaluated. Flow-weighted concentration and load ha(-1) of the two hormones were measured in drainage and runoff. Soil concentrations of estradiol and testosterone were measured. Based on comparisons to the conventional fertilizer (and control) treatments, poultry litter did not add to the flow-weighted concentration or load ha(-1) of either estradiol or testosterone in subsurface drainage or surface runoff. Significant differences were, however, observed between tillage treatments: flow-weighted concentrations of estradiol were greater for no-till than conventional-till plots of the June irrigation; and runoff loads of both estradiol and testosterone were less from no-till than conventional-till plots for the November irrigation. Although the differences between no-till and conventional-tillage appeared to affect the hydrologic transport of both hormones, the differences appeared to have inconsequential environmental impact.
NASA Astrophysics Data System (ADS)
Schulthess, U.; Krupnik, T. J.; Ahmed, Z. U.; McDonald, A. J.
2015-04-01
Remote sensing data are nowadays being acquired within short intervals and made available at a low cost or for free. This opens up opportunities for new remote sensing applications, such as the characterization of entire regions to identify most suitable areas for technology targeting. Increasing population growth and changing dietary habits in South Asia call for higher cereal production to ensure future food security. In the Delta area of Bangladesh, surface water is considered to be available in quantities large enough to support intensification by adding an irrigated dry season crop. Fuel-efficient, low lift axial flow pumps have shown to be suitable to carry water to fields that are within a buffer of four hundred meters of the rivers. However, information on how and where to target surface water irrigation efforts is currently lacking. We describe the opportunities and constraints encountered in developing a procedure to identify cropland for which axial flow pumps could be successfully deployed upon in a 43'000 km2 area. First, we isolated cropland and waterways using Landsat 5 and 7 scenes using image segmentation followed by classification with the random forest algorithm. Based on Landsat 7 and 8 scenes, we extracted maximum dry season enhanced vegetation index (EVI) values, which we classified into fallow, low-, and high-intensity cropland for the last three years. Last, we investigated the potential for surface water irrigation on fallow and low-intensity land by applying a cropping risk matrix to address the twin threats of soil and water salinity. Our analysis indicates that there are at least 20,000 ha of fallow land under the low-risk category, while more than 100,000 ha of low-intensity cropland can be brought into intensified production. This information will aid in technology targeting for the efficient deployment of surface water irrigation as a tool for intensification.
Sainju, Upendra M; Stevens, William B; Caesar-TonThat, Thecan; Liebig, Mark A; Wang, Jun
2014-05-01
Little information exists about how global warming potential (GWP) is affected by management practices in agroecosystems. We evaluated the effects of irrigation, tillage, crop rotation, and N fertilization on net GWP and greenhouse gas intensity (GHGI or GWP per unit crop yield) calculated by soil respiration (GWP and GHGI) and organic C (SOC) (GWP and GHGI) methods after accounting for CO emissions from all sources (irrigation, farm operations, N fertilization, and greenhouse gas [GHG] fluxes) and sinks (crop residue and SOC) in a Lihen sandy loam from 2008 to 2011 in western North Dakota. Treatments were two irrigation practices (irrigated vs. nonirrigated) and five cropping systems (conventional-till malt barley [ L.] with N fertilizer [CTBN], conventional-till malt barley with no N fertilizer [CTBO], no-till malt barley-pea [ L.] with N fertilizer [NTB-P], no-till malt barley with N fertilizer, and no-till malt barley with no N fertilizer [NTBO]). While CO equivalents were greater with irrigation, tillage, and N fertilization than without, NO and CH fluxes were 2 to 218 kg CO eq. ha greater in nonirrigated NTBN and irrigated CTBN than in other treatments. Previous year's crop residue and C sequestration rate were 202 to 9316 kg CO eq. ha greater in irrigated NTB-P than in other treatments. Compared with other treatments, GWP and GWP were 160 to 9052 kg CO eq. ha lower in irrigated and nonirrigated NTB-P. Similarly, GHGI and GHGI were lower in nonirrigated NTB-P than in other treatments. Regardless of irrigation practices, NTB-P may lower net GHG emissions more than other treatments in the northern Great Plains. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
NASA Astrophysics Data System (ADS)
Ren, Dongyang; Xu, Xu; Hao, Yuanyuan; Huang, Guanhua
2016-01-01
Water saving in irrigation is a key issue in the upper Yellow River basin. Excessive irrigation leads to water waste, water table rising and increased salinity. Land fragmentation associated with a large dispersion of crops adds to the agro-hydrological complexity of the irrigation system. The model HYDRUS-1D, coupled with the FAO-56 dual crop coefficient approach (dualKc), was applied to simulate the water and salt movement processes. Field experiments were conducted for maize, sunflower and watermelon crops in the command area of a typical irrigation canal system in Hetao Irrigation District during 2012 and 2013. The model was calibrated and validated in three crop fields using two-year experimental data. Simulations of soil moisture, salinity concentration and crop yield fitted well with the observations. The irrigation water use was then evaluated and results showed that large amounts of irrigation water percolated due to over-irrigation but their reuse through capillary rise was also quite large. That reuse was facilitated by the dispersion of crops throughout largely fragmented field, thus with fields reusing water percolated from nearby areas due to the rapid lateral migration of groundwater. Beneficial water use could be improved when taking this aspect into account, which was not considered in previous researches. The non-beneficial evaporation and salt accumulation into the root zone were found to significantly increase during non-growth periods due to the shallow water tables. It could be concluded that when applying water saving measures, close attention should be paid to cropping pattern distribution and groundwater control in association with irrigation scheduling and technique improvement.
Water and solute balances as a basis for sustainable irrigation agriculture
NASA Astrophysics Data System (ADS)
Pla-Sentís, Ildefonso
2015-04-01
The growing development of irrigated agriculture is necessary for the sustainable production of the food required by the increasing World's population. Such development is limited by the increasing scarcity and low quality of the available water resources and by the competitive use of the water for other purposes. There are also increasing problems of contamination of surface and ground waters to be used for other purposes by the drainage effluents of irrigated lands. Irrigation and drainage may cause drastic changes in the regime and balance of water and solutes (salts, sodium, contaminants) in the soil profile, resulting in problems of water supply to crops and problems of salinization, sodification and contamination of soils and ground waters. This is affected by climate, crops, soils, ground water depth, irrigation and groundwater composition, and by irrigation and drainage management. In order to predict and prevent such problems for a sustainable irrigated agriculture and increased efficiency in water use, under each particular set of conditions, there have to be considered both the hydrological, physical and chemical processes determining such water and solute balances in the soil profile. In this contribution there are proposed the new versions of two modeling approaches (SOMORE and SALSODIMAR) to predict those balances and to guide irrigation water use and management, integrating the different factors involved in such processes. Examples of their application under Mediterranean and tropical climate conditions are also presented.
NASA Astrophysics Data System (ADS)
Bartholomeus, Ruud; van den Eertwegh, Gé; Worm, Bas; Cirkel, Gijsbert; van Loon, Arnaut; Raat, Klaasjan
2017-04-01
Agricultural crop yields depend largely on soil moisture conditions in the root zone. Climate change leads to more prolonged drought periods that alternate with more intensive rainfall events. With unaltered water management practices, reduced crop yield due to drought stress will increase. Therefore, both farmers and water management authorities search for opportunities to manage risks of decreasing crop yields. Available groundwater sources for irrigation purposes are increasingly under pressure due to the regional coexistence of land use functions that are critical to groundwater levels or compete for available water. At the same time, treated wastewater from industries and domestic wastewater treatment plants are quickly discharged via surface waters towards sea. Exploitation of these freshwater sources may be an effective strategy to balance regional water supply and agricultural water demand. We present results of two pilot studies in drought sensitive regions in the Netherlands, concerning agricultural water supply through reuse of industrial and domestic treated wastewater. In these pilots, excess wastewater is delivered to the plant root zone through sub-irrigation by drainage systems. Sub-irrigation is a subsurface irrigation method that can be more efficient than classical, aboveground irrigation methods using sprinkler installations. Domestic wastewater treatment plants in the Netherlands produce annually 40-50mm freshwater. A pilot project has been setup in the eastern part of the Netherlands, in which treated wastewater is applied to a corn field by sub-irrigation during the growing seasons of 2015 and 2016, using a climate adaptive drainage system. The chemical composition of treated domestic wastewater is different from infiltrating excess rainfall water and natural groundwater. In the pilot project, the bromide-chloride ratio and traces of pharmaceuticals in the treated wastewater are used as a tracer to describe water and solute transport in the soil system. Focus of this pilot study is on quantifying potential contamination of both the root zone and the deeper groundwater with pharmaceutical residues. We have installed a field monitoring network at several locations in the vadose zone and the local groundwater system, which enables us to measure vertical solute profiles in the soil water by taking samples. Based on field data obtained during the experiments, combined with SWAP (1D) and Hydrus (2D) model simulations, flow and transport of the sub-irrigated treated wastewater are quantified. In the south of The Netherlands, the Bavaria Beer Brewery abstracts a large volume of groundwater and discharges treated wastewater to local surface water which transports the water rapidly out of the region. At the same time, neighboring farmers invest in sprinkler irrigation systems to maintain their crop production during drought periods. In this region, increasing pressure is put on the regional groundwater and surface water availability. Within a pilot study, a sub-irrigation system has been installed, by using subsurface drains, interconnected through a collector drain, and connected to an inlet control basin for the treated wastewater to enter the drainage system. We combine both process-based modeling of the soil-plant-atmosphere system and field experiments to i) investigate the amount of water that needs to be and that can be sub-irrigated, and ii) quantify the effect on soil moisture availability and herewith reduced needs for aboveground irrigation.
Wang, Yunqi; Zhang, Yinghua; Ji, Wei; Yu, Peng; Wang, Bin; Li, Jinpeng; Han, Meikun; Xu, Xuexin; Wang, Zhimin
2016-01-01
The effects of cultivar mixture cropping on yield, biomass, and water use efficiency (WUE) in winter wheat (Triticum aestivum L.) were investigated under non-irrigation (W0, no irrigation during growth stage), one time irrigation (W1, irrigation applied at stem elongation) and two times irrigation (W2, irrigation applied at stem elongation and anthesis) conditions. Nearly 90% of cultivar mixture cropping treatments experienced an increase in grain yield as compared with the mean of the pure stands under W0, those for W1 and W2 were 80% and 85%, respectively. Over 75% of cultivar mixture cropping treatments got greater biomass than the mean of the pure stands under the three irrigation conditions. Cultivar mixture cropping cost more water than pure stands under W0 and W1, whereas the water consumption under W2 decreased by 5.9%–6.8% as compared with pure stands. Approximately 90% of cultivar mixtures showed an increase of 5.4%–34.5% in WUE as compared with the mean of the pure stands, and about 75% of cultivar mixtures had 0.8%–28.5% higher WUE than the better pure stands under W0. Similarly, there were a majority of mixture cropping treatments with higher WUE than the mean and the better one of the pure stands under W1 and W2. On the whole, proper cultivar mixture cropping could increase yield and WUE, and a higher increase in WUE occurred under limited irrigation condition. PMID:27362563
Remote-Sensing-Based Evaluation of Relative Consumptive Use Between Flood- and Drip-Irrigated Fields
NASA Astrophysics Data System (ADS)
Martinez Baquero, G. F.; Jordan, D. L.; Whittaker, A. T.; Allen, R. G.
2013-12-01
Governments and water authorities are compelled to evaluate the impacts of agricultural irrigation on economic development and sustainability as water supply shortages continue to increase in many communities. One of the strategies commonly used to reduce such impacts is the conversion of traditional irrigation methods towards more water-efficient practices. As part of a larger effort by the New Mexico Interstate Stream Commission to understand the environmental and economic impact of converting from flood irrigation to drip irrigation, this study evaluates the water-saving effectiveness of drip irrigation in Deming, New Mexico, using a remote-sensing-based technique combined with ground data collection. The remote-sensing-based technique used relative temperature differences as a proxy for water use to show relative differences in crop consumptive use between flood- and drip-irrigated fields. Temperature analysis showed that, on average, drip-irrigated fields were cooler than flood-irrigated fields, indicating higher water use. The higher consumption of water by drip-irrigated fields was supported by a determination of evapotranspiration (ET) from all fields using the METRIC Landsat-based surface energy balance model. METRIC analysis yielded higher instantaneous ET for drip-irrigated fields when compared to flood-irrigated fields and confirmed that drip-irrigated fields consumed more water than flood-irrigated fields planted with the same crop. More water use generally results in more biomass and hence higher crop yield, and this too was confirmed by greater relative Normalized Difference Vegetation Index for the drip irrigated fields. Results from this study confirm previous estimates regarding the impacts of increased efficiency of drip irrigation on higher water consumption in the area (Ward and Pulido-Velazquez, 2008). The higher water consumption occurs with drip because, with the limited water supplies and regulated maximum limits on pumping amounts, the higher efficiency of drip enables producers to convert larger percentages of pumped ground-water into evapotranspiration and reduces the ';return' of percolation ';losses' back to the ground-water system that previously re-recharged the aquifer. This study illustrates the usefulness of remote sensing techniques to evaluate spatial patterns of ET by different irrigation methods. These results illustrate a first-step quantitative tool that can be used by water resources managers in formulation of policy to limit net water consumption and maintain reliable water supply sources.
Water Stress & Biomass Monitoring and SWAP Modeling of Irrigated Crops in Saratov Region of Russia
NASA Astrophysics Data System (ADS)
Zeyliger, Anatoly; Ermolaeva, Olga
2016-04-01
Development of modern irrigation technologies are balanced between the need to maximize production and the need to minimize water use which provides harmonious interaction of irrigated systems with closely-spaced environment. Thus requires an understanding of complex interrelationships between landscape and underground of irrigated and adjacent areas in present and future conditions aiming to minimize development of negative scenarios. In this way in each irrigated areas a combination of specific factors and drivers must be recognized and evaluated. Much can be obtained by improving the efficiency use of water applied for irrigation. Modern RS monitoring technologies offers the opportunity to develop and implement an effective irrigation control program permitting today to increase efficiency of irrigation water use. These technologies provide parameters with both high temporal and adequate spatial needed to monitor agrohydrological parameters of irrigated agricultural crops. Combination of these parameters with meteorological and biophysical parameters can be used to estimate crop water stress defined as ratio between actual (ETa) and potential (ETc) evapotranspiration. Aggregation of actual values of crop water stress with biomass (yield) data predicted by agrohydrological model based on weather forecasting and scenarios of irrigation water application may be used for indication of both rational timing and amount of irrigation water allocation. This type of analysis facilitating an efficient water management can be easily extended to irrigated areas by developing maps of water efficiency application serving as an irrigation advice system for farmers at his fields and as a decision support tool for the authorities on the large perimeter irrigation management. This contribution aims to communicate an illustrative explanation about the practical application of a data combination of agrohydrological modeling and ground & space based monitoring. For this aim some results of analyzing water stress during growing season of 2012 and yielded biomass of crops three types of crops alfalfa, corn and soya irrigated by sprinkling machines at left bank of Volga River at Saratov Region of Russia are presented and analyzed. For that a combination of data received from satellite, local meteorological station and farmers as well as SWAP model was used. Analyze of data sets of monitored water deficit of each crop averaged for irrigation period was done by linear regression with yielded biomass values. Following analyze of effectiveness of irrigation water application was done by SWAP agrohydrological model.
NASA Astrophysics Data System (ADS)
Monaco, Eugenia; De Mascellis, Roberto; Riccardi, Maria; Basile, Angelo; D'Urso, Guido; Magliulo, Vincenzo; Tedeschi, Anna
2016-04-01
In Mediterranean Countries the proper management of water resources is important for the preservation of actual production systems. The possibility to manage water resources is possible especially in the greenhouses systems. The challenge to manage the soil in greenhouse farm can be a strategy to maintain both current production systems both soil conservation. In Campania region protected crops (greenhouses and tunnels) have a considerable economic importance both for their extension in terms of surface harvested and also for their production in terms of yields. Agricultural production in greenhouse is closely related to the micro-climatic condition but also to the physical and agronomic characteristics of the soil-crop system. The protected crops have an high level of technology compare to the other production systems, but the irrigation management is still carried out according to empirical criteria. The rational management of the production process requires an appropriate control of climatic parameters (temperature, humidity, wind) and agronomical inputs (irrigation, fertilization,). All these factors need to be monitored as well is possible, in order to identify the optimal irrigation schedule. The aim of this work is to implement a Decision Support system -DSS- for irrigation management in greenhouses focused on a smart irrigation control based on observation of the agro-climatic parameters monitored with an advanced wireless sensors network. The study is conducted in a greenhouse farm of 6 ha located in the district of Salerno were seven plots were cropped with rocket. Preliminary a study of soils proprieties was conducted in order to identify spatial variability of the soil in the farm. So undisturbed soil samples were collected to define chemical and physical proprieties; moreover soil hydraulic properties were determined for two soils profiles deemed representation of the farm. Then the wireless sensors, installed at different depth in the soils, determined volumetric water content (VWC) by measuring the dielectric constant of the soil using frequency domain technology (FDR). The data acquired real time were used to determine water balance with a physically based model Hydrus 1D. The results show how the model is able to identify the optimal irrigation schedule as function of soil proprieties and crop needs. Keywords: irrigation, DSS, rocket, water content
NASA Astrophysics Data System (ADS)
Roy, A.; Inamdar, A. B.
2016-12-01
Major part of Godavari River Basin is intensely drought prone and climate vulnerable in the Western Maharashtra State, India. The economy of the state depends on the agronomic productivity of this region. So, it is necessary to regulate the effects of existing and upcoming hydro-meteorological advances in various strata. This study investigates and maps the surface water resources availability and vegetation, their decadal deviations with multi-temporal LANDSAT images; and finally quantifies the agricultural adaptations. This work involves the utilization of Remote Sensing and GIS with Hydrological modeling. First, climatic trend analysis is carried out with NCEP dataset. Then, multi-temporal LANDSAT images are classified to determine the decadal LULC changes and correlated to the community level hydrological demand. Finally, NDVI, NDWI and SWAT model analysis are accomplished to determine irrigated and non-irrigated cropping area for identifying the agricultural adaptations. The analysis shows that the mean value of annual and monsoon rainfall is significantly decreasing, whereas the mean value of annual and summer temperature is increasing significantly and the winter temperature is decreasing. The analysis of LANDSAT images shows that the surface water availability is highly dependent on climatic conditions. Barren-lands are most dynamic during the study period followed by, vegetation, and water bodies. The spatial extent of barren-lands is increased drastically during the climate vulnerable years replacing the vegetation and surface water bodies. Hence, the barren lands are constantly increasing and the vegetation cover is linearly decreasing, whereas the water extent is changing either way in a random fashion. There appears a positive correlation between surface water and vegetation occurrence; as they are fluctuating in a similar fashion in all the years. The vegetation cover is densely replenished around the dams and natural water bodies which serve as the water supply stations for the irrigation purposes. Moreover, there is a shift to non-irrigated and less water demanding crops, from more water demanding crops, which is a conspicuous adaptation. Hence, the study shows there are alteration in meteorological predictors, land cover, agricultural practices and surface water availability.
Crop-specific seasonal estimates of irrigation-water demand in South Asia
NASA Astrophysics Data System (ADS)
Biemans, Hester; Siderius, Christian; Mishra, Ashok; Ahmad, Bashir
2016-05-01
Especially in the Himalayan headwaters of the main rivers in South Asia, shifts in runoff are expected as a result of a rapidly changing climate. In recent years, our insight into these shifts and their impact on water availability has increased. However, a similar detailed understanding of the seasonal pattern in water demand is surprisingly absent. This hampers a proper assessment of water stress and ways to cope and adapt. In this study, the seasonal pattern of irrigation-water demand resulting from the typical practice of multiple cropping in South Asia was accounted for by introducing double cropping with monsoon-dependent planting dates in a hydrology and vegetation model. Crop yields were calibrated to the latest state-level statistics of India, Pakistan, Bangladesh and Nepal. The improvements in seasonal land use and cropping periods lead to lower estimates of irrigation-water demand compared to previous model-based studies, despite the net irrigated area being higher. Crop irrigation-water demand differs sharply between seasons and regions; in Pakistan, winter (rabi) and monsoon summer (kharif) irrigation demands are almost equal, whereas in Bangladesh the rabi demand is ~ 100 times higher. Moreover, the relative importance of irrigation supply versus rain decreases sharply from west to east. Given the size and importance of South Asia improved regional estimates of food production and its irrigation-water demand will also affect global estimates. In models used for global water resources and food-security assessments, processes like multiple cropping and monsoon-dependent planting dates should not be ignored.
Assessment of water use and its productivity in the Spanish irrigation district "Río Adaja"
NASA Astrophysics Data System (ADS)
Rodriguez-Sinobas, Leonor; Naroua, Iliassou; Sánchez-Calvo, Raúl
2015-04-01
A study of the assessment of the irrigation water use has been carried out in the Spanish irrigation District "Río Adaja" that has analyzed the water use efficiency and the water productivity indicators for the main crops during the first three years of operation (2010/2011, 2011/2012 and 2012/2013). A soil water balance model was applied taking into account climatic data for the nearby weather station and soil properties. Crop water requirements were calculated by the FAO Penman-Monteith with the application of the dual crop coefficient and by considering the readily available soil water content (RAW) concept. Likewise, productivity was measured by the indexes: annual relative irrigation supply (ARIS), annual relative water supply (ARWS), relative rainfall supply (RRS), the water productivity (WP), the evapotranspiration water productivity (ETWP), and the irrigation water productivity (IWP). The results show that the irrigation district applied deficit irrigation in most crops (ARIS<1), and also improved water productivity. This was higher in 2010/2011 which showed the highest effective precipitation Pe. The IWP (€/m3) index varied among crops with the highest values for onion (4.14), potato (2.79), carrot (1.37) and barley (1.21) for the first year and, onion (1.98), potato (1.69), carrot (1.70) and barley (1.16) in the second year. Thus, these crops would be a proper cropping pattern to maximize the gross income in the irrigation district.
NASA Astrophysics Data System (ADS)
Löw, Fabian; Biradar, Chandrashekhar; Fliemann, Elisabeth; Lamers, John P. A.; Conrad, Christopher
2017-07-01
Improving crop area and/or crop yields in agricultural regions is one of the foremost scientific challenges for the next decades. This is especially true in irrigated areas because sustainable intensification of irrigated crop production is virtually the sole means to enhance food supply and contribute to meeting food demands of a growing population. Yet, irrigated crop production worldwide is suffering from soil degradation and salinity, reduced soil fertility, and water scarcity rendering the performance of irrigation schemes often below potential. On the other hand, the scope for improving irrigated agricultural productivity remains obscure also due to the lack of spatial data on agricultural production (e.g. crop acreage and yield). To fill this gap, satellite earth observations and a replicable methodology were used to estimate crop yields at the field level for the period 2010/2014 in the Fergana Valley, Central Asia, to understand the response of agricultural productivity to factors related to the irrigation and drainage infrastructure and environment. The results showed that cropping pattern, i.e. the presence or absence of multi-annual crop rotations, and spatial diversity of crops had the most persistent effects on crop yields across observation years suggesting the need for introducing sustainable cropping systems. On the other hand, areas with a lower crop diversity or abundance of crop rotation tended to have lower crop yields, with differences of partly more than one t/ha yield. It is argued that factors related to the infrastructure, for example, the distance of farms to the next settlement or the density of roads, had a persistent effect on crop yield dynamics over time. The improvement potential of cotton and wheat yields were estimated at 5%, compared to crop yields of farms in the direct vicinity of settlements or roads. In this study it is highlighted how remotely sensed estimates of crop production in combination with geospatial technologies provide a unique perspective that, when combined with field surveys, can support planners to identify management priorities for improving regional production and/or reducing environmental impacts.
Determination of kinetic energy applied by center pivot sprinklers
USDA-ARS?s Scientific Manuscript database
The kinetic energy of discrete drops impacting a bare soil surface is generally observed to lead to a drastic reduction in water infiltration rate due to soil surface seal formation. Under center pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy development can...
Online irrigation service for fruit und vegetable crops at farmers site
NASA Astrophysics Data System (ADS)
Janssen, W.
2009-09-01
Online irrigation service for fruit und vegetable crops at farmers site by W. Janssen, German Weather Service, 63067 Offenbach Agrowetter irrigation advice is a product which calculates the present soil moisture as well as the soil moisture to be expected over the next 5 days for over 30 different crops. It's based on a water balance model and provides targeted recommendations for irrigation. Irrigation inputs according to the soil in order to avoid infiltration and, as a consequence thereof, the undesired movement of nitrate and plant protectants into the groundwater. This interactive 'online system' takes into account the user's individual circumstances such as crop and soil characteristics and the precipitation and irrigation amounts at the user's site. Each user may calculate up to 16 different enquiries simultaneously (different crops or different emergence dates). The user can calculate the individual soil moistures for his fields with a maximum effort of 5 minutes per week only. The sources of water are precipitation and irrigation whereas water losses occur due to evapotranspiration and infiltration of water into the ground. The evapotranspiration is calculated by multiplying a reference evapotranspiration (maximum evapotranspiration over grass) with the so-called crop coefficients (kc values) that have been developed by the Geisenheim Research Centre, Vegetable Crops Branch. Kc values depending on the crop and the individual plant development stage. The reference evapotranspiration is calculated from a base weather station user has chosen (out of around 500 weather stations) using Penman method based on daily values. After chosen a crop and soil type the user must manually enter the precipitation data measured at the site, the irrigation water inputs and the dates for a few phenological stages. Economical aspects can be considered by changing the values of soil moisture from which recommendations for irrigation start from optimal to necessary plant supply. Previous comparative measurements carried out by the Agricultural Administration of Baden-Württemberg relating to potatoes, onions, vine stocks, and strawberries agreed very well with the calculations.
NASA Astrophysics Data System (ADS)
Al-Ghobari, Hussein M.; Mohammad, Fawzi S.
2011-12-01
Intelligent irrigation technologies have been developed in recent years to apply irrigation to turf and landscape plants. These technologies are an evapotranspiration (ET)-based irrigation controller, which calculates ET for local microclimate. Then, the controller creates a program for loading and communicating automatically with drip or sprinkler system controllers. The main objective of this study was to evaluate the effectiveness of the new ET sensors in ability to irrigate agricultural crops and to conserve water use for crop in arid climatic conditions. This paper presents the case for water conservation using intelligent irrigation system (IIS) application technology. The IIS for automating irrigation scheduling was implemented and tested with sprinkle and drip irrigation systems to irrigate wheat and tomato crops. Another irrigation scheduling system was also installed and operated as another treatment, which is based on weather data that retrieved from an automatic weather station. This irrigation control system was running in parallel to the former system (IIS) to be control experiments for comparison purposes. However, this article discusses the implementation of IIS, its installation, testing and calibration of various components. The experiments conducted for one growing season 2009-2010 and the results were represented and discussed herein. Data from all plots were analyzed, which were including soil water status, water consumption, and crop yield. The initial results indicate that up to 25% water saving by intelligent irrigation compared to control method, while maintaining competing yield. Results show that the crop evapotranspiration values for control experiments were higher than that of ET-System in consistent trend during whole growth season. The analysis points out that the values of the two treatments were somewhat close to each other's only in the initial development stages. Generally, the ET-System, with some modification was precise in controlling irrigation water and has been proven to be a good mean to determine the water requirements for crops and to schedule irrigation automatically.
Optimizing preplant irrigation for maize under limited water in the High Plains
USDA-ARS?s Scientific Manuscript database
Due to inadequate well capacities, many farmers cannot meet inseason crop evapotranspiration demands. Some farmers apply preplant (preseason) irrigation to buffer the crop between irrigation or rainfall events during the season. A simulation study was conducted to assess the effect of preplant irrig...
Comparison of methods to determine the microbial quality of alternative irrigation waters
USDA-ARS?s Scientific Manuscript database
The availability of water for crop irrigation is decreasing due to droughts, population growth, and pollution. Implementation of Food Safety and Modernization Act (FSMA) for irrigation water standards discourages growers to use poor microbial quality water for produce crop irrigation. We evaluated m...
Determination of irrigation pumpage in parts of Kearny and Finney Counties, southwestern Kansas
Lindgren, R.J.
1982-01-01
Irrigation pumpage was determined for parts of Kearny and Finney Counties in Southwestern Kansas using crop-acreage data and consumptive, irrigation-water requirements. Irrigated acreages for 1974-80 were compiled for wheat, grain sorghum, corn, and alfalfa using records from the U.S. Agricultural Stabilization and Conservation Service. Consumptive-irrigation requirements were computed using a soil-moisture model. The model tabulated monthly soil-moisture and crop-water demand for various crops and computed the volume of irrigation water needed to maintain the available moisture at 50% for loamy soils or at 60% for sandy soils. Irrigated acres in the study area increased from 265,000 acres during 1974 to 321,000 acres during 1980. Irrigation pumpage increased from 584,000 acre-feet during 1974 to 738,000 acre-feet during 1980. Decreased consumptive-irrigation requirements during 1979 resulted in a comparatively small irrigation-pumpage estimate of 458,000 acre-feet. (USGS)
NASA Astrophysics Data System (ADS)
Johnson, M. S.; Lathuilliere, M. J.; Morillas, L.; Dalmagro, H. J.; D'Acunha, B.; Kim, Y.; Suarez, A.; Couto, E. G.
2017-12-01
In this talk, we will summarize results obtained using three tropical agricultural water observatories in Guanacaste, Costa Rica and Mato Grosso, Brazil. These flux towers and associated sensors enable detailed assessments of carbon use and water use efficiencies for crops under rain-fed and irrigated conditions. In addition to directly assessing water consumption from crops via eddy covariance, determination of water footprints and water use efficiencies using sensors and integrating it with remotely sensed data make it possible to (i) evaluate and compare different irrigation systems used in the study regions (drip, pivot and flood irrigation), (ii) assess the effect of irrigation over the local water balance to identify vulnerabilities associated with intensive water extraction for irrigation, and (iii) study the effect of inter-annual water availability fluctuations on crop water use. We conclude by comparing volumetric water footprints for crops, their carbon footprints, and water and carbon use efficiencies of crops produced under business-as-usual and alternative soil and water management scenarios.
Tran, Quynh K; Schwabe, Kurt A; Jassby, David
2016-09-06
Water scarcity has become a critical problem in many semiarid and arid regions. The single largest water use in such regions is for crop irrigation, which typically relies on groundwater and surface water sources. With increasing stress on these traditional water sources, it is important to consider alternative irrigation sources for areas with limited freshwater resources. One potential irrigation water resource is treated wastewater for agricultural fields located near urban centers. In addition, treated wastewater can contribute an appreciable amount of necessary nutrients for plants. The suitability of reclaimed water for specific applications depends on water quality and usage requirements. The main factors that determine the suitability of recycled water for agricultural irrigation are salinity, heavy metals, and pathogens, which cause adverse effects on human, plants, and soils. In this paper, we develop a regional water reuse decision-support model (RWRM) using the general algebraic modeling system to analyze the cost-effectiveness of alternative treatment trains to generate irrigation water from reclaimed wastewater, with the irrigation water designed to meet crop requirements as well as California's wastewater reuse regulations (Title 22). Using a cost-minimization framework, least-cost solutions consisting of treatment processes and their intensities (blending ratios) are identified to produce alternative irrigation sources for citrus and turfgrass. Our analysis illustrates the benefits of employing an optimization framework and flexible treatment design to identify cost-effective blending opportunities that may produce high-quality irrigation water for a wide range of end uses.
Evaluating the crop coefficient using spectral reflectance
Heilman, J. L.; Heilman, W. E.; Moore, Donald G.
1982-01-01
Significant linear relationships were found between PVI and percent cover (r2 = 0.911), and between Kc and percent cover (r2 = 0.815). In addition, the position of the PVl intersection on the soil background line changed as a result of soil moisture increases following irrigation, even at high percent cover. Thus, once experimental relationships between Kc and crop growth are established, a mean Kc can be determined from spectral estimates of stage of development and the soil background component of PVI can be used to adjust the mean K, for increased evaporation following irrigation because the ratio of actual to potential evapotranspiration will approach 1 when the soil surface is wet.
Application of MODFLOW’s farm process to California’s Central Valley
Faunt, Claudia; Hanson, Randall T.; Schmid, Wolfgang; Belitz, Kenneth
2008-01-01
landscape processes. The FMP provides coupled simulation of the ground-water and surface-water components of the hydrologic cycle for irrigated and non-irrigated areas. A dynamic allocation of ground-water recharge and ground-water pumping is simulated on the basis of residual crop-water demand after surface-water deliveries and root uptake from shallow ground water. The FMP links with the Streamflow Routing Package SFR1) to facilitate the simulated conveyance of surface-water deliveries. Ground-water Pumpage through both single-aquifer and multi-node wells, irrigation return flow, and variable irrigation efficiencies also are simulated by the FMP. The simulated deliveries and ground-water pumpage in the updated model reflect climatic differences, differences among defined water-balance regions, and changes in the waterdelivery system, during the 1961–2003 simulation period. The model is designed to accept forecasts from Global Climate Models (GCMs) to simulate the potential effects on surface-water delivery, ground-water pumpage, and ground-water storage in response to climate change. The model provides a detailed transient analysis of changes in ground-water availability in relation to climatic variability, urbanization, and changes in irrigated agriculture.
USDA-ARS?s Scientific Manuscript database
Irrigation of food and fiber crops worldwide continues to increase. Nitrogen (N) from fertilizers is a major source of the potent greenhouse gas nitrous oxide (N2O) in irrigated cropping systems. Nitrous oxide emissions data are scarce for crops in the arid Western US. The objective of these studies...
USDA-ARS?s Scientific Manuscript database
The availability of water for crop irrigation is decreasing due to droughts, population growth, and pollution. The Food Safety and Modernization Act (FSMA) standards for irrigation water may also discourage growers to use poor microbial quality water for produce crop irrigation. Reclaimed water use ...
USDA-ARS?s Scientific Manuscript database
The availability of water for crop irrigation is decreasing due to droughts, population growth, and pollution. Food Safety and Modernization Act (FSMA) for irrigation water standards may also discourage growers to use poor microbial quality water for produce crop irrigation. Reclaimed water use for ...
NASA Astrophysics Data System (ADS)
Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin
2016-04-01
The risk of rice production has increased notably due to climate change in Taiwan. To respond to growing agricultural water shortage without affecting normal food production in the future, the application of water-saving irrigation will be a substantial resolution. However, the adoption of water-saving irrigation may result in the reducing of groundwater recharge because continuous flooding in the paddy fields could be regarded as an important source for groundwater recharge. The aim of this study was to evaluate the irrigation water-saving benefit and groundwater recharge deficit when adopting the System of Rice Intensification, known as SRI methodology, in the Choushui River alluvial fan (the largest groundwater pumping and the most important rice-cropping region in central Taiwan). The three-dimensional finite element groundwater model, FEMWATER, was applied to simulate the infiltration process and groundwater recharge under SRI methodology and traditional irrigation schemes including continuous irrigation, and rotational irrigation in two rice-crop periods with hydro-climatic data of 2013. The irrigation water use was then calculated by water balance. The results showed that groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reduced 3.6% and 1.6% in the first crop period, and reduced 3.2% and 1.6% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. However, the SRI methodology achieved notably water-saving benefit compared to the disadvantage of reducing the groundwater recharge amount. The field irrigation requirement amount of SRI methodology was significantly lower than those of traditional irrigation schemes, saving 37% and 20% of irrigation water in the first crop period, and saving 53% and 35% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. Therefore, the amount of groundwater pumping for irrigation water use can be reduced when adopting the SRI methodology in the future. The reducing of groundwater recharge could be supplemented by using 1,500 hectares of fallow paddy fields, located at proximal-fan region, as recharge pools in the wet season. The adoption of water-saving irrigation would be helpful for the relevant government agency to formulate the integral water resource management strategies in this region. Keywords:Groundwater recharge, SRI, FEMWATER, Field irrigation requirement
Liang, X Q; Chen, Y X; Nie, Z Y; Ye, Y S; Liu, J; Tian, G M; Wang, G H; Tuong, T P
2013-10-01
Resource-conserving irrigation and fertilizer management practices have been developed for rice systems which may help address water quality concerns by reducing N and P losses via surface runoff. Field experiments under three treatments, i.e., farmers' conventional practice (FCP), alternate wetting and drying (AWD), and AWD integrated with site-specific nutrient management (AWD + SSNM) were carried out during two rice seasons at two sites in the southwest Yangtze River delta region. Across site years, results indicated that under AWD irrigation (i.e., AWD and AWD + SSNM), water inputs were reduced by 13.4~27.5 % and surface runoff was reduced by 30.2~36.7 % compared to FCP. When AWD was implemented alone, total N and P loss masses via surface runoff were reduced by 23.3~30.4 % and 26.9~31.7 %, respectively, compared to FCP. However, nutrient concentrations of surface runoff did not decrease under AWD alone. Under AWD + SSNM, total N and P loss masses via surface runoff were reduced to a greater extent than AWD alone (39.4~47.6 % and 46.1~48.3 % compared to FCP, respectively), while fertilizer inputs and N surpluses significantly decreased and rice grain yields increased relative to FCP. Therefore, by more closely matching nutrient supply with crop demand and reducing both surface runoff and nutrient concentrations of surface runoff, our results demonstrate that integration of AWD and SSNM practices can mitigate N and P losses via surface runoff from rice fields while maintaining high yields.
Pawlowski, Meghan N; Crow, Susan E; Meki, Manyowa N; Kiniry, James R; Taylor, Andrew D; Ogoshi, Richard; Youkhana, Adel; Nakahata, Mae
2017-01-01
Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHG emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO2), as methane was oxidized and nitrous oxide (N2O) emission was very low even following fertilization. High N2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO2 flux. Deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated belowground. In the first two years of cultivation napiergrass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield.
Meki, Manyowa N.; Kiniry, James R.; Taylor, Andrew D.; Ogoshi, Richard; Youkhana, Adel; Nakahata, Mae
2017-01-01
Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHG emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO2), as methane was oxidized and nitrous oxide (N2O) emission was very low even following fertilization. High N2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO2 flux. Deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated belowground. In the first two years of cultivation napiergrass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield. PMID:28052075
A Site-sPecific Agricultural water Requirement and footprint Estimator (SPARE:WATER 1.0)
NASA Astrophysics Data System (ADS)
Multsch, S.; Al-Rumaikhani, Y. A.; Frede, H.-G.; Breuer, L.
2013-07-01
The agricultural water footprint addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). By considering site-specific properties when calculating the crop water footprint, this methodology can be used to support decision making in the agricultural sector on local to regional scale. We therefore developed the spatial decision support system SPARE:WATER that allows us to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirements and water footprints are assessed on a grid basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume inefficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water is defined as the water needed to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept, we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr-1 for 2008, with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional estimation of crop water footprints.
Summary of reported agriculture and irrigation water use in White County, Arkansas, 1991
Holland, T.W.; Manning, C.A.; Stafford, K.L.
1993-01-01
This report summarizes the 1991 water-use reporting through the Conservation District Office in White County, Arkansas. The number of withdrawal registrations for White County was 1,365 (1,146 groundwater and 219 surface water). Water withdrawals reported during the registration process total 1.37 Mgal/d (0.95 Mgal/d groundwater and 0.42 Mgal/d surface water) for agriculture and 69.91 Mgal/d (43.78 Mgal/d groundwater and 26.13 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was supplied to 46,315 acres of land to irrigate rice, sorghum, corn, soybeans, milo, cash grains, hay, vegetables, berries, grapes, fruit trees, sod, and unknown crop as well as for the agricultural uses of animal aquaculture, minnows, ducks, and sport clubs.
Van Metre, P.C.; Seevers, Paul
1991-01-01
A method for estimating ground-water pumpage for irrigation was developed for the Columbia Plateau in eastern Washington. The method combines water-application rates estimated from pumpage data with acreage of irrigated crops that was mapped by using Landsat imagery. The study area consisted of Grant, Lincoln, Adams, and Franklin Counties, an area of approximately 8,900 square miles, and accounts for approximately three-fourths of the ground-water pumpage in the Columbia Plateau in eastern Washington. Data from two passes of Landsat's multispectral scanner were analyzed by using a spectral band ratioing procedure to map irrigated crops for the study area. Data from one pass of Landsat's thematic mapper, covering approximately two-thirds of the study area, also were analyzed for determining irrigated crops in the area resulting in a 6-percent improvement in accuracy over the multispectral scanner analysis. A total of 576 annual water-application rates associated with particular crops, for the 1982 through 1985 seasons, were calculated. A regression equation was developed for estimating annual water-application rates as a function of crop type, annual precipitation, irrigation system type, and available water capacity of the soil. Crops were grouped into three water-use categories: (1) small grains, primarily wheat and barley; (2) high water-use crops consisting of corn, alfalfa, and potatoes; and (3) miscellaneous vegetable and row crops. Annual water-application rates, expressed as a depth of water, then were multiplied by irrigated area determined by Landsat to estimate a volume of water pumped for irrigation for 1985-620,000 acre-feet. An assessment of accuracy for estimating pumpage for 28 of the sites showed that total predicted pumpage was within 4 percent of the total observed pumpage.
Microbial Survey of Pennsylvania Surface Water Used for Irrigating Produce Crops.
Draper, Audrey D; Doores, Stephanie; Gourama, Hassan; LaBorde, Luke F
2016-06-01
Recent produce-associated foodborne illness outbreaks have been attributed to contaminated irrigation water. This study examined microbial levels in Pennsylvania surface waters used for irrigation, relationships between microbial indicator organisms and water physicochemical characteristics, and the potential use of indicators for predicting the presence of human pathogens. A total of 153 samples taken from surface water sources used for irrigation in southeastern Pennsylvania were collected from 39 farms over a 2-year period. Samples were analyzed for six microbial indicator organisms (aerobic plate count, Enterobacteriaceae, coliform, fecal coliforms, Escherichia coli, and enterococci), two human pathogens (Salmonella and E. coli O157), and seven physical and environmental characteristics (pH, conductivity, turbidity, air and water temperature, and sampling day and 3-day-accumulated precipitation levels). Indicator populations were highly variable and not predicted by water and environmental characteristics. Only five samples were confirmed positive for Salmonella, and no E. coli O157 was detected in any samples. Predictive relationships between microbial indicators and the occurrence of pathogens could therefore not be determined.
NASA Technical Reports Server (NTRS)
Martinko, E. A. (Principal Investigator); Poracsky, J.; Kipp, E. R.; Krieger, H.
1980-01-01
The activity concentrated on identifying crop and irrigation data sources for the eight states within the High Plains Aquifer and making contacts concerning the nature of these data. A mail questionnaire was developed to gather specific data not routinely reported through standard data collection channels. Input/output routines were designed for High Plains crop and irrigation data and initial statistical data on crops were input to computer files.
Effects on crops of irrigation with treated municipal wastewaters.
Fasciolo, G E; Meca, M I; Gabriel, E; Morábito, J
2002-01-01
The fertilizing potential of treated municipal wastewater (oxidation ditch) and crop sanitary acceptability for direct human consumption were evaluated in Mendoza, Argentina. Two experiments were performed on a pilot plot planted with garlic (1998) and onions (1999) using furrow irrigation with three types of water in 10 random blocks: treated effluent (2.5 x 10(3) MPN Escherichia coli/100 ml, 3 helminth eggs/l, and Salmonella (positive); and well water (free of microorganisms), with and without fertilizer. Two responses were evaluated: (1) crop yield, and (2) crop microbiological quality for human consumption at different times after harvest. Crop yields were compared using Variance analysis. Crops' sanitary acceptability was assessed using a two-class sampling program for Salmonella (n=10; c=0), and a three-class program for E. coli (n=5, c=2, M=10(3) and m=10 MPN/g) as proposed by the International Commission on Microbiological Specifications for Foods (ICMSF) for fresh vegetables. Wastewater irrigation acted as well water with fertilizer, increasing garlic and onion yields by 10% and 15%, respectively, compared to irrigation with well water with no fertilizer. Wastewater-irrigated garlic reached sanitary acceptability 90 days after harvest, once attached roots and soil were removed. Onions, which were cleaned immediately after harvest, met this qualification earlier than garlic (55 days). Neither the wastewater-irrigated crops nor the control crops were microbiologically acceptable for consumption raw at harvest.
Mok, Hoi-Fei; Hamilton, Andrew J.
2014-01-01
Many farmers in water-scarce regions of developing countries use wastewater to irrigate vegetables and other agricultural crops, a practice that may expand with climate change. There is a number of health risks associated with wastewater irrigation for human food crops, particularly with surface irrigation techniques common in the developing world. The World Health Organization recommends using quantitative microbial risk assessment (QMRA) to determine if the irrigation scheme meets health standards. However, only a few vegetables have been studied for wastewater risk and little information is known about the disease burden of wastewater-irrigated vegetable consumption in China. To bridge this knowledge gap, an experiment was conducted to determine volume of water left on Asian vegetables and lettuce after irrigation. One hundred samples each of Chinese chard (Brassica rapa var. chinensis), Chinese broccoli (Brassica oleracea var. alboglabra), Chinese flowering cabbage (Brassica rapa var. parachinensis), and lettuce (Lactuca sativa) were harvested after overhead sprinkler irrigation. Chinese broccoli and flowering cabbage were found to capture the most water and lettuce the least. QMRAs were then constructed to estimate rotavirus disease burden from consumption of wastewater-irrigated Asian vegetables in Beijing. Results indicate that estimated risks from these reuse scenarios exceed WHO guideline thresholds for acceptable disease burden for wastewater use, signifying that reduction of pathogen concentration or stricter risk management is necessary for safe reuse. Considering the widespread practice of wastewater irrigation for food production, particularly in developing countries, incorporation of water retention factors in QMRAs can reduce uncertainty regarding health risks for consumers worldwide. PMID:24576153
Suarez, Donald L; Wood, James D; Lesch, Scott M
2008-01-01
The sodium adsorption ratio (SAR) and salinity criteria for water suitability for irrigation have been developed for conditions where irrigation water is the only water source. It is not clear that these criteria are applicable to environments where there is a combination of rain and irrigation during the growing season. The interaction of rainfall with irrigation water is expected to result in increased sodicity hazard because of the low electrical conductivity of rain. In this study we examined the effects of irrigation waters of SAR 2, 4, 6, 8, and 10 mmol(1/2) L(-1/2) and electrical conductivities of 1 and 2 dS m(-1) on the infiltration rate of two soils with alternating cycles of rain (simulated with a rainfall sprinkler) and irrigation water, separated by drying cycles. The infiltration rate of surface samples from two soils, Kobase silty clay (fine, smectitic, frigid, Torrertic Haplustept) and Glendive very fine sandy loam (coarse-loamy, mixed superactive, calcareous, frigid Aridic Ustifluvent) were evaluated under alfalfa (Medicago sativa) cropped conditions for over 140 d and under full canopy cover. Reductions in infiltration were observed for both soils for SAR above 2, and the reductions became more severe with increasing SAR. Saturated hydraulic conductivity measurements taken from undisturbed cores at the end of the experiment were highly variable, suggesting that in situ infiltration measurements may be preferred when evaluating SAR effects.
Methods to estimate irrigated reference crop evapotranspiration - a review.
Kumar, R; Jat, M K; Shankar, V
2012-01-01
Efficient water management of crops requires accurate irrigation scheduling which, in turn, requires the accurate measurement of crop water requirement. Irrigation is applied to replenish depleted moisture for optimum plant growth. Reference evapotranspiration plays an important role for the determination of water requirements for crops and irrigation scheduling. Various models/approaches varying from empirical to physically base distributed are available for the estimation of reference evapotranspiration. Mathematical models are useful tools to estimate the evapotranspiration and water requirement of crops, which is essential information required to design or choose best water management practices. In this paper the most commonly used models/approaches, which are suitable for the estimation of daily water requirement for agricultural crops grown in different agro-climatic regions, are reviewed. Further, an effort has been made to compare the accuracy of various widely used methods under different climatic conditions.
NASA Astrophysics Data System (ADS)
Seidel, Sabine J.; Werisch, Stefan; Barfus, Klemens; Wagner, Michael; Schütze, Niels; Laber, Hermann
2014-05-01
The increasing worldwide water scarcity, costs and negative off-site effects of irrigation are leading to the necessity of developing methods of irrigation that increase water productivity. Various approaches are available for irrigation scheduling. Traditionally schedules are calculated based on soil water balance (SWB) calculations using some measure of reference evaporation and empirical crop coeffcients. These crop-specific coefficients are provided by the FAO but are also available for different regions (e.g. Germany). The approach is simple but there are several inaccuracies due to simplifications and limitations such as poor transferability. Crop growth models - which simulate the main physiological plant processes through a set of assumptions and calibration parameter - are widely used to support decision making, but also for yield gap or scenario analyses. One major advantage of mechanistic models compared to empirical approaches is their spatial and temporal transferability. Irrigation scheduling can also be based on measurements of soil water tension which is closely related to plant stress. Advantages of precise and easy measurements are able to be automated but face difficulties of finding the place where to probe especially in heterogenous soils. In this study, a two-year field experiment was used to extensively evaluate the three mentioned irrigation scheduling approaches regarding their efficiency on irrigation water application with the aim to promote better agronomic practices in irrigated horticulture. To evaluate the tested irrigation scheduling approaches, an extensive plant and soil water data collection was used to precisely calibrate the mechanistic crop model Daisy. The experiment was conducted with white cabbage (Brassica oleracea L.) on a sandy loamy field in 2012/13 near Dresden, Germany. Hereby, three irrigation scheduling approaches were tested: (i) two schedules were estimated based on SWB calculations using different crop coefficients, and (ii) one treatment was automatically drip irrigated using tensiometers (irrigation of 15 mm at a soil tension of -250 hPa at 30 cm soil depth). In treatment (iii), the irrigation schedule was estimated (using the same critera as in the tension-based treatment) applying the model Daisy partially calibrated against data of 2012. Moreover, one control treatment was minimally irrigated. Measured yield was highest for the tension-based treatment with a low irrigation water input (8.5 DM t/ha, 120 mm). Both SWB treatments showed lower yields and higher irrigation water input (both 8.3 DM t/ha, 306 and 410 mm). The simulation model based treatment yielded lower (7.5 DM t/ha, 106 mm) mainly due to drought stress caused by inaccurate simulation of the soil water dynamics and thus an overestimation of the soil moisture. The evaluation using the calibrated model estimated heavy deep percolation under both SWB treatments. Targeting the challenge to increase water productivity, soil water tension-based irrigation should be favoured. Irrigation scheduling based on SWB calculation requires accurate estimates of crop coefficients. A robust calibration of mechanistic crop models implies a high effort and can be recommended to farmers only to some extent but enables comprehensive crop growth and site analyses.
Analytical steady-state solutions for water-limited cropping systems using saline irrigation water
USDA-ARS?s Scientific Manuscript database
Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mod...
USDA-ARS?s Scientific Manuscript database
Accurate estimates of daily crop evapotranspiration (ET) are needed for efficient irrigation management, especially in arid and semi-arid irrigated regions where crop water demand exceeds rainfall. The impact of inaccurate ET estimates can be tremendous in both irrigation cost and the increased dema...
NASA Astrophysics Data System (ADS)
Labbassi, Kamal; Akdim, Nadia; Alfieri, Silvia Maria; Menenti, Massimo
2014-05-01
Irrigation performance may be evaluated for different objectives such as equity, adequacy, or effectiveness. We are using two performance indicators: IP2 measures the consistency of the allocation of the irrigation water with gross Crop Water requirements, while IP3 measures the effectiveness of irrigation by evaluating the increase in crop transpiration between the case of no irrigation and the case of different levels of irrigation. To evaluate IP3 we need to calculate the soil water balance for the two cases. We have developed a system based on the hydrological model SWAP (Soil Water atmosphere Plant) to calculate spatial and temporal patterns of crop transpiration T(x, y, t) and of the vertical distribution of soil water content θ(x, y, z, t). On one hand, in the absence of ground measurement of soil water content to validate and evaluate the precision of the estimated one, a possibility would be to use satellite retrievals of top soil water content, such as the data to be provided by SMAP. On the other hand, to calculate IP3 we need root zone rather than top soil water content. In principle, we could use the model SWAP to establish a relationship between the top soil and root zone water content. Such relationship could be a simple empirical one or a data assimilation procedure. In our study area (Doukkala- Morocco) we have assessed the consistency of the water allocation with the actual irrigated area and crop water requirements (CWR) by using a combination of multispectral satellite image time series (i,e RapidEye (REIS), SPOT4 (HRVIR1) and Landsat 8 (OLI) images acquired during the 2012/2013 agricultural season). To obtain IP2 (x, y, t) we need to determine ETc (x, y, t). We have applied two (semi)empirical approaches: the first one is the Kc-NDVI method, based on the correlation between the Near Difference Vegetation Index (NDVI) and the value of crop coefficient (kc); the second one is the analytical approach based on the direct application of Penman-Monteith equation with reflectance-based estimates of canopy biophysical variables, such as surface albedo (r), leaf area index (LAI) and crop height (hc). The validation of spatial results using the dual crop coefficient approach (kcb) showed that the satellite-based estimates of ETc corresponded well with ground-based ETc i.e, R²=0.75 and RMSE=0.79 versus R²=0.73 and RMSE=0.89 for respectively kc-NDVI and analytical approach. To monitor IP3 (x, y, t) with the SWAP model we mapped soil hydrological properties combining soil maps with grain size analysis of a number of samples, and agricultural crops using multi-temporal classification of NDVI time series. The assessment of irrigation performance in term of adequacy between requirement and allocation showed that CWR are much larger than water supply for entire area, this mismatch is improved in the beginning of the growing season by means of Irrigation water requirement (IWR) and even more using the net irrigation water requirement (NIWR) estimated using SWAP model. We expect that the availability of SMAP data products will significantly improve the reliability and temporal sampling of our indicators.
Brumbelow, Kelly; Georgakakos, Aris P.
2000-01-01
Past assessments of climate change on U.S. agriculture have mostly focused on changes in crop yield. Few studies have included the entire conterminous U.S., and few studies have assessed changing irrigation requirements. None have included the effects of changing soil moisture characteristics as determined by changing climatic forcing. This study assesses changes in irrigation requirements and crop yields for five crops in the areas of the U.S. where they have traditionally been grown. Physiologically-based crop models are used to incorporate inputs of climate, soils, agricultural management, and drought stress tolerance. Soil moisture values from a macroscale hydrologic model run under a future climate scenario are used to initialize soil moisture content at the beginning of each growing season. Historical crop yield data is used to calibrate model parameters and determine locally acceptable drought stress as a management parameter. Changes in irrigation demand and crop yield are assessed for both means and extremes by comparing results for atmospheric forcing close to the present climate with those for a future climate scenario. Assessments using the Canadian Center for Climate Modeling and Analysis General Circulation Model (CGCM1) indicate greater irrigation demands in the southern U.S. and decreased irrigation demands in the northern and western U.S. Crop yields typically increase except for winter wheat in the southern U.S. and corn. Variability in both irrigation demands and crop yields increases in most cases. Assessment results for the CGCM1 climate scenario are compared to those for the Hadley Centre for Climate Prediction and Research GCM (HadCM2) scenario for southwestern Georgia. The comparison shows significant differences in irrigation and yield trends, both in magnitude and direction. The differences reflect the high forecast uncertainty of current GCMs. Nonetheless, both GCMs indicate higher variability in future climatic forcing and, consequently, in the response of agricultural systems.
NASA Technical Reports Server (NTRS)
Hatfield, J. L.; Millard, J. P.; Reginato, R. J.; Jackson, R. D.; Idso, S. B.; Pinter, P. J., Jr.; Goettelman, R. C.
1980-01-01
Crop stress measured using thermal infrared emission is evaluated with the stress-degree-day (SDD) concept. Throughout the season, the accumulation of SDD during the reproductive stage of growth is inversely related to yield. This relationship is shown for durum wheat, hard red winter wheat, barley, grain sorghum and soybeans. It is noted that SDD can be used to schedule irrigations for maximizing yields and for applying remotely sensed data to management of water resources. An airborne flight with a thermal-IR scanner was used to examine the variability in temperature that may exist from one field to another and to determine realistic within-field temperature variations. It was found that the airborne and the ground-based data agreed very well and that there was less variability in the fields that were completely covered with crops than those of bare soil.
Herrero, Juan; Betrán, Jesús A.; Ritchie, Glen
2018-01-01
A key issue for agriculture in irrigated arid lands is the control of soil salinity, and this is one of the goals for irrigated districts when changing from flood to sprinkling irrigation. We combined soil sampling, proximal electromagnetic induction, and satellite data to appraise how soil salinity and its distribution along a previously flood-irrigated field evolved after its transformation to sprinkling. We also show that the relationship between NDVI (normalized difference vegetation index) and ECe (electrical conductivity of the soil saturation extracts) mimics the production function between yield and soil salinity. Under sprinkling, the field had a double crop of barley and then sunflower in 2009 and 2011. In both years, about 50% of the soil of the entire studied field—45 ha—had ECe < 8 dS m−1, i.e., allowing barley cultivation, while the percent of surface having ECe ≥ 16 dS m−1 increased from 8.4% in 2009 to 13.7% in 2011. Our methodology may help monitor the soil salinity oscillations associated with irrigation management. After quantifying and mapping the soil salinity in 2009 and 2011, we show that barley was stunted in places of the field where salinity was higher. Additionally, the areas of salinity persisted after the subsequent alfalfa cropping in 2013. Application of differential doses of water to the saline patches is a viable method to optimize irrigation water distribution and lessen soil salinity in sprinkler-irrigated agriculture. PMID:29462981
Casterad, Mª Auxiliadora; Herrero, Juan; Betrán, Jesús A; Ritchie, Glen
2018-02-17
A key issue for agriculture in irrigated arid lands is the control of soil salinity, and this is one of the goals for irrigated districts when changing from flood to sprinkling irrigation. We combined soil sampling, proximal electromagnetic induction, and satellite data to appraise how soil salinity and its distribution along a previously flood-irrigated field evolved after its transformation to sprinkling. We also show that the relationship between NDVI (normalized difference vegetation index) and ECe (electrical conductivity of the soil saturation extracts) mimics the production function between yield and soil salinity. Under sprinkling, the field had a double crop of barley and then sunflower in 2009 and 2011. In both years, about 50% of the soil of the entire studied field-45 ha-had ECe < 8 dS m-1, i.e., allowing barley cultivation, while the percent of surface having ECe ≥ 16 dS m-1 increased from 8.4% in 2009 to 13.7% in 2011. Our methodology may help monitor the soil salinity oscillations associated with irrigation management. After quantifying and mapping the soil salinity in 2009 and 2011, we show that barley was stunted in places of the field where salinity was higher. Additionally, the areas of salinity persisted after the subsequent alfalfa cropping in 2013. Application of differential doses of water to the saline patches is a viable method to optimize irrigation water distribution and lessen soil salinity in sprinkler-irrigated agriculture.
Crop response to biochar under differing irrigation levels in the southeastern USA
USDA-ARS?s Scientific Manuscript database
Application of biochar to soils is hypothesized to increase crop yield. Crop productivity impacts of biochar application in Southeastern cropping systems consisting of peanut (Arachis hypogaea L.), corn (Zea mays L.), and cotton (Gossypium hirsutum L.) produced under varying rates of irrigation have...
Adaptive management of irrigation and crops' biodiversity: a case study on tomato
NASA Astrophysics Data System (ADS)
De Lorenzi, Francesca; Alfieri, Silvia Maria; Basile, Angelo; Bonfante, Antonello; Monaco, Eugenia; Riccardi, Maria; Menenti, Massimo
2013-04-01
We have assessed the impacts of climate change and evaluated options to adapt irrigation management in the face of predicted changes of agricultural water demand. We have evaluated irrigation scheduling and its effectiveness (versus crop transpiration), and cultivars' adaptability. The spatial and temporal variations of effectiveness and adaptability were studied in an irrigated district of Southern Italy. Two climate scenarios were considered: reference (1961-90) and future (2021-2050) climate, the former from climatic statistics, and the latter from statistical downscaling of general circulation models (AOGCM). Climatic data consist of daily time series of maximum and minimum temperature, and daily rainfall on a grid with a spatial resolution of 35 km. The work was carried out in the Destra Sele irrigation scheme (18.000 ha. Twenty-five soil units were identified and their hydrological properties were determined (measured or estimated from texture through pedo-transfer functions). A tomato crop, in a rotation typical of the area, was considered. A mechanistic model of water flow in the soil-plant-atmosphere system (SWAP) was used to study crop water requirements and water consumption. The model was calibrated and validated in the same area for many different crops. Tomato crop input data and model parameters were estimated on the basis of scientific literature and assumed to be generically representative of the species. Simulations were performed for reference and future climate, and for different irrigation scheduling options. In all soil units, six levels of irrigation volumes were applied: full irrigation (100%), deficit irrigation (80%, 60%, 40%, 20%), no irrigation. From simulation runs, indicators of soil water availability were calculated, moreover the marginal increases of transpiration per unit of irrigation volume, i.e. the effectiveness of irrigation (ΔT/I), were computed, in both climate scenarios. Indicators and marginal increases were used to evaluate the tomato crop adaptability to future climate. To this purpose, for several tomato cultivars, threshold values of their yield responses to soil water availability were determined (data from scientific literature). Cultivars' threshold values were evaluated, in all soil units, against the indicators' values, for irrigation levels with different ΔT/I. Less water intensive cultivars and irrigation volumes that optimize transpiration (and yield) could thus be identified in both climate scenarios, and irrigation management scenarios were determined taking into account soils' hydrological properties, crop biodiversity, and efficient use of water resource. The work was carried out within the Italian national project AGROSCENARI funded by the Ministry for Agricultural, Food and Forest Policies (MIPAAF, D.M. 8608/7303/2008) Keywords: climate change, adaptation, simulation models, deficit irrigation, water resource efficiency, SWAP
Limited irrigation of corn-based no-till crop rotations in West Central Great Plains
USDA-ARS?s Scientific Manuscript database
Due to numerous alternatives in crop sequence and changes in crop yield and price, finding the most profitable crop rotation for an area is a continuous research challenge. The objective of this study was to evaluate 1-, 2-, 3-, and 4-yr limited irrigation corn (Zea mays L.)-based crop rotations for...
Improving Crop Productions Using the Irrigation & Crop Production Model Under Drought
NASA Astrophysics Data System (ADS)
Shin, Y.; Lee, T.; Lee, S. H.; Kim, J.; Jang, W.; Park, S.
2017-12-01
We aimed to improve crop productions by providing optimal irrigation water amounts (IWAs) for various soils and crops using the Irrigation & Crop Production (ICP) model under various hydro-climatic regions. We selected the Little Washita (LW 13/21) and Bangdong-ri sites in Oklahoma (United States of America) and Chuncheon (Republic of Korea) for the synthetic studies. Our results showed that the ICP model performed well for improving crop productions by providing optimal IWAs during the study period (2000 to 2016). Crop productions were significantly affected by the solar radiation and precipitation, but the maximum and minimum temperature showed less impact on crop productions. When we considerd that the weather variables cannot be adjusted by artifical activities, irrigation might be the only solution for improving crop productions under drought. Also, the presence of shallow ground water (SGW) table depths higlhy influences on crop production. Although certainties exist in the synthetic studies, our results showed the robustness of the ICP model for improving crop productions under the drought condition. Thus, the ICP model can contribute to efficient water management plans under drought in regions at where water availability is limited.
NASA Astrophysics Data System (ADS)
Malek, K.; Adam, J. C.; Stockle, C.; Brady, M.; Yoder, J.
2015-12-01
The western US is expected to experience more frequent droughts with higher magnitudes and persistence due to the climate change, with potentially large impacts on agricultural productivity and the economy. Irrigated farmers have many options for minimizing drought impacts including changing crops, engaging in water markets, and switching irrigation technologies. Switching to more efficient irrigation technologies, which increase water availability in the crop root zone through reduction of irrigation losses, receives significant attention because of the promise of maintaining current production with less. However, more efficient irrigation systems are almost always more capital-intensive adaptation strategy particularly compared to changing crops or trading water. A farmer's decision to switch will depend on how much money they project to save from reducing drought damages. The objective of this study is to explore when (and under what climate change scenarios) it makes sense economically for farmers to invest in a new irrigation system. This study was performed over the Yakima River Basin (YRB) in Washington State, although the tools and information gained from this study are transferable to other watersheds in the western US. We used VIC-CropSyst, a large-scale grid-based modeling framework that simulates hydrological processes while mechanistically capturing crop water use, growth and development. The water flows simulated by VIC-CropSyst were used to run the RiverWare river system and water management model (YAK-RW), which simulates river processes and calculates regional water availability for agricultural use each day (i.e., the prorationing ratio). An automated computational platform has been developed and programed to perform the economic analysis for each grid cell, crop types and future climate projections separately, which allows us to explore whether or not implementing a new irrigation system is economically viable. Results of this study indicate that climate change could justify the investment in new irrigation systems during this century, but the timing of a farmer's response is likely to depend on a variety of factors, including changes in the frequency and magnitude of drought events, current irrigation systems, climatological characteristics within the basin, and crop type.
NASA Astrophysics Data System (ADS)
Fandiño, María; Martínez, Emma M.; Rey, Benjamín J.; Cancela, Javier J.
2015-04-01
Different studies have tackled the conceptual and terminological study of crop water use indicators, mainly water use efficiency (WUE) and water productivity (WP) (Pereira et al., 2012; Scheierling et al., 2014). The high number of stakeholders, working about agricultural water use (hydrology and hydrogeology, civil and irrigation engineering, agronomy and crop physiology, economics), has hindered the real improvement thereof, from a multidisciplinary perspective. For example, Flexas et al. (2010) reviewed the future improvements in water use efficiency in grapevines, from a physiological approach. In this study, two grapevine cultivars, priority in Galicia (Spain): 'Godello' (DO Valdeorras) and 'Albariño' (DO Rías Baixas, two locations), was assessed in relation to four water productivity index, focus on irrigation systems, agronomy and crop physiology aspects, during a wet year (2012). All WP index was referred to farm yield level (kg ha-1); where the denominator applied to WPTWU, include all components of soil water balance; to WPTWUfarm, introduced rainfall and irrigation depth; to WPIrrig, only irrigation depth applied; and to WPT, crop transpiration was used. In the last index, SIMDualKc model was used to partitioning crop evapotranspiration and cover crop transpiration. Different ranges of values was obtained for both cultivars, WPTWUfarm was higher in cv 'Godello' than in cv 'Albariño', 3.8 and 0.9 kg m-3 respectively. Average value to WPIrrig has showed: 17.6 kg m-3 for cv 'Albariño' and 15.5 kg m-3 for cv 'Godello', due to a reduction of 60% of irrigation depth in DO Rías Baixas. However, for both locations, higher WPIrrig was obtained to drip irrigation system versus subsurface drip irrigation. WPT showed a different tendency, rain-fed 'Godello' and surface drip irrigation 'Albariño' treatments obtained higher values (6.8 and 3.6 kg m-3), with higher WPT to cv 'Godello' for all treatments versus 'Albariño'. Results had showed that water productivity indexes are cultivar depending, similar values was achieved in near locations (data not showed). Special care must be taken when analysing water productivity indexes at the farm level, considering identical irrigation depth, density, canopy management system, age of the plantation, management practices, among other factors, which may affect of water consumed or supplied to the vineyard. Agronomical economic aspects should be studied, taken into account irrigation systems cost and benefit crop yield, at basin scale. Temperate viticulture should pursue greater WUE and WP, identifying the most productive cultivars adapted to near-future climate conditions. References: Flexas J, Galmés J, Gallé A, Gulías J, Pou A, Ribas-Carbo M, Tomàs M, Medrano H (2010). Improving water use efficiency in grapevines: potential physiological targets for biotechnological improvement. Australian Journal of Grape and Wine Research, 16(s1):106-121 Pereira LS, Cordery I, Iacovides I (2012). Improved indicators of water use performance and productivity for sustainable water conservation and saving. Agricultural Water Management, 108:39-51 Scheierling SM, Treguer DO, Booker JF, Decker E (2014). How to assess agricultural water productivity? looking for water in the agricultural productivity and efficiency literature. Looking for Water in the Agricultural Productivity and Efficiency Literature (July 1, 2014). World Bank Policy Research Working Paper, (6982)
Precision irrigation for improving crop water management
USDA-ARS?s Scientific Manuscript database
Precision irrigation is gaining attention by the agricultural industry as a means to optimize water inputs, reduce environmental degradation from runoff or deep percolation and maintain crop yields. This presenation will discuss the mechanical and software framework of the irrigation scheduling sup...
Global Estimates of Trace Gas Fluxes Affected by Land Use Change and Irrigation of Major Crops
NASA Astrophysics Data System (ADS)
Ojima, D. S.; del Grosso, S.; Parton, W. J.; Keough, C.
2005-12-01
Cropland conversions have altered many fertile regions of the earth and have modified the biogeochemical and hydrological cycling in these regions. These croplands are significant sources of N trace gas emissions however, the extent of changing trace gas emission due to land management changes and irrigation need further analysis. We use the DAYCENT biogeochemical model which is a daily time step version of the CENTURY model. DAYCENT simulates fluxes of N2O between croplands and the atmosphere for major crop types, and allows for a dynamic representation of GHG fluxes that accounts for environmental conditions, soil characteristics, climate, specific crop qualities, and fertilizer and irrigation management practices. DAYCENT is applied to all world cropland regions. Global datasets of weather, soils, native vegetation and cropping fractions were mapped to an approximate 2° x 2° resolution. Non-spatial data (such as planting date and fertilizer application rates) were assigned as point values for each region (i.e. country), and were assumed to be similar within crop types across the region. Three major crops were simulated (corn, wheat and soybeans) under both irrigated and non-irrigated conditions. Results indicate that N2O emission for maize and soy bean increase between 3 to 10%, where as wheat emission decline by about 1% when irrigated systems are compared to non-irrigated systems.
USDA-ARS?s Scientific Manuscript database
Water shortages are responsible for the greatest crop losses around the world and are expected to worsen. In arid areas where agriculture is dependent on irrigation, various forms of deficit irrigation management have been suggested to optimize crop yields for available soil water. The relationshi...
USDA-ARS?s Scientific Manuscript database
Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mod...
USDA-ARS?s Scientific Manuscript database
Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mode...
NASA Astrophysics Data System (ADS)
Zaccaria, Daniele; Marino, Giulia; Whiting, Michael; Sanden, Blake; Ferguson, Louise; Lampinen, Bruce; Kent, Eric; Snyder, Richard; Grattan, Stephen; Little, Cayle
2017-04-01
Pistachio acreage is rapidly expanding in California thanks to its economic profitability and capacity to grow and produce in salt-affected soils. Our team at University of California is updating information on actual water use (ET) of mature pistachio orchards grown on saline soils under micro-irrigation methods. Actual Evapotranspiration (ETa) and Crop Coefficients (Ka) were determined for the 2015 and 2016 crop seasons on four pistachio orchards grown in the San Joaquin Valley (SJV) on grounds with increasing levels of soil-water salinity, using the residual of energy balance method with a combination of eddy covariance and surface renewal equipment. Tree canopy cover, light interception, and plant water status across the orchards were also measured and evaluated. Our preliminary results show that salinity strongly affects the tree water use, resulting in 10-30% less ET for medium to high salt-affected soils. Salinity also showed a strong effect on tree water status and light interception, as suggested by values of the Midday Stem Water Potential (ΨSWP) around 10 to 15-bar lower in salt-affected than in the control orchard, and by the intercepted Photosynthetic Active Radiation (PAR) decreasing from 75% in the control orchard to 25% in the severely salt affected grounds. The crop coefficient values we observed in this study are lower than those commonly used for irrigation scheduling in the SJV, suggesting that pistachio growers could better tailor irrigation management to the actual site-specific orchard conditions (e.g. canopy features and soil-water salinity) if they are provided updated information. Improved irrigation practices could likely lead to significant water savings and thus improve the resource-efficiency and competitiveness of pistachio production in the SJV. Keywords: Pistacia vera L., salinity, stem water potential, surface renewal, canopy cover.
Distillation irrigation: a low-energy process for coupling water purification and drip irrigation
Constantz, J.
1989-01-01
A method is proposed for combining solar distillation and drip irrigation to simultaneously desalinize water and apply this water to row crops. In this paper, the basic method is illustrated by a simple device constructed primarily of sheets of plastic, which uses solar energy to distill impaired water and apply the distillate to a widely spaced row crop. To predict the performance of the proposed device, an empirical equation for distillate production, dp, is developed from reported solar still production rates, and a modified Jensen-Haise equation is used to calculate the potential evapotranspiration, et, for a row crop. Monthly values for et and dp are calculated by using a generalized row crop at five locations in the Western United States. Calculated et values range from 1 to 22 cm month-1 and calculated dp values range from 2 to 11 cm month-1, depending on the location, the month, and the crop average. When the sum of dp plus precipitation, dp + P, is compared to et for the case of 50% distillation irrigation system coverage, the results indicate that the crop's et is matched by dp + P, at the cooler locations only. However, when the system coverage is increased to 66%, the crop's et is matched by dp + P even at the hottest location. Potential advantages of distillation irrigation include the ability: (a) to convert impaired water resources to water containing no salts or sediments; and (b) to efficiently and automatically irrigate crops at a rate that is controlled primarily by radiation intensities. The anticipated disadvantages of distillation irrigation include: (a) the high costs of a system, due to the large amounts of sheeting required, the short lifetime of the sheeting, and the physically cumbersome nature of a system; (b) the need for a widely spaced crop to reduce shading of the system by the crop; and (c) the production of a concentrated brine or precipitate, requiring proper off-site disposal. ?? 1989.
NASA Astrophysics Data System (ADS)
Cary, L.; Kloppmann, W.; Battilani, A.; Bertaki, M.; Blagojevic, S.; Chartzoulakis, K.; Dalsgaard, A.; Forslund, A.; Jovanovic, Z.; Kasapakis, I.
2009-04-01
The safe use of treated domestic wastewater for irrigation needs to address the risks for humans (workers, exposed via contact with irrigation water, soil, crops and food, consumers, exposed via ingestion of fresh and processed food), for animals (via ingestion of crops an soil), for the crops and agricultural productivity (via salinity and trace element uptake), for soil (via accumulation or release of pollutants) as well as for surface, groundwaters and the associated ecosystems (via runoff and infiltration, Kass et al., 2005, Bouwer, 2000). A work package in the EU FP5 project SAFIR is dedicated to study the impact of wastewater irrigation on the soil-water-plant-product system. Its monitoring program comprises pathogens and inorganic pollutants, including both geogenic and potentially anthropogenic trace elements in the aim to better understand soil-irrigation water interactions. The SAFIR field study sites are found in China, Italy, Crete, and Serbia. A performance evaluation of SAFIR-specific treatment technology through the monitoring of waste water and irrigation water quality was made through waste water chemical and microbiological qualities, which were investigated upstream and downstream of the SAFIR specific treatment three times per season. Irrigation water transits through the uppermost soil decimetres to the crop roots. The latter will become, in the course of the irrigation season, the major sink of percolating water, together with evaporation. The water saving irrigation techniques used in SAFIR are surface and subsurface drip irrigation. The investigation of the solid soil phase concentrates on the root zone as main transit and storage compartment for pollutants and, eventually, pathogens. The initial soil quality was assessed through a sampling campaign before the onset of the first year irrigation; the soil quality has been monitored throughout three years under cultivation of tomatoes or potatoes. The plot layout for each of the study sites allows comparing different combinations of (1) water quality, including tap water as a reference, (2) irrigation techniques, and (3) irrigation strategies (including full irrigation, partial root drying, RDI). The replication of each of the combinations on three different plots takes into account the local variations of soil properties and allows a proper statistical treatment. Reactions of the infiltrating water with the soil solid phase are important for the solute cycling, temporary fixation and remobilisation of trace pollutants. The type of reaction (sorption, co-precipitation…) and the reactive mineral phases will also determine the availability of trace elements for the plant and determine the passage towards crops and products. Therefore it is important to assess the soil water quality, directly or indirectly. Direct measurements of soil water imply soil water sampling through an appropriate system; porous cups were installed on the Cretan, Italian and Chinese sites. Indirect evaluation of water-soil interactions can be obtained through sequential extractions. The combination of a variable input function (through diffuse pollution, irrigation, fertigation) and of variable MTE mobility in soils can be expected to lead to short term variations in soil metal concentrations even if such short term variations have been rarely investigated (Féder, 2001; Cary and Trolard, 2008). The sampling focused upon the fully irrigated plots given that the potential impact of irrigation water quality on soil and plant quality can be expected higher for fully irrigated soils compared to other irrigation strategies. Samples were taken within the soil volume of potential influence around each of the drip emitters. This volume varies depending on the nature of the soil and the irrigation system so that each site adopted a specific protocol. For all experiments, three sampling campaigns were scheduled for each irrigation season: at pre-planting, at the end of irrigation, at harvest. The geochemical evolution of soil properties over the 3 years shows significant variations in major and minor elements, especially trace metallic elements. It implies the role of the cultivated plant as a sink of elements which leads to direct loss of elements in the soil system. Bouwer, H., 2000. Groundwater problems caused by irrigation with sewage effluent. Journal of Environmental Health 63, 17-20. Cary L., Trolard F. (2008). Metal mobility in the ground water of a paddy field in Camargue (South eastern France). Journal of Geochemical Exploration 96/2-3 : 132-143. Féder, 2001. Dynamique des processus d'oxydo-reduction dans les sols hydromorphes, These de l'Universite Aix Marseille III. Kass, A. Gavrieli, I. Yechieli, Y. Vengosh A.and Starinsky, A., 2005. The impact of freshwater and wastewater irrigation on the chemistry of shallow groundwater: a case study from the Israeli Coastal Aquifer, Journal of Hydrology, 300, 314-331.
NASA Astrophysics Data System (ADS)
Chukalla, Abebe; Krol, Maarten; Hoekstra, Arjen
2016-04-01
Reducing water footprints (WF) in irrigated crop production is an essential element in water management, particularly in water-scarce areas. To achieve this, policy and decision making need to be supported with information on marginal cost curves that rank measures to reduce the WF according to their cost-effectiveness and enable the estimation of the cost associated with a certain WF reduction target, e.g. towards a certain reasonable WF benchmark. This paper aims to develop marginal cost curves (MCC) for WF reduction. The AquaCrop model is used to explore the effect of different measures on evapotranspiration and crop yield and thus WF that is used as input in the MCC. Measures relate to three dimensions of management practices: irrigation techniques (furrow, sprinkler, drip and subsurface drip); irrigation strategies (full and deficit irrigation); and mulching practices (no mulching, organic and synthetic mulching). A WF benchmark per crop is calculated as resulting from the best-available production technology. The marginal cost curve is plotted using the ratios of the marginal cost to WF reduction of the measures as ordinate, ranking with marginal costs rise with the increase of the reduction effort. For each measure, the marginal cost to reduce WF is estimated by comparing the associated WF and net present value (NPV) to the reference case (furrow irrigation, full irrigation, no mulching). The NPV for each measure is based on its capital costs, operation and maintenances costs (O&M) and revenues. A range of cases is considered, including: different crops, soil types and different environments. Key words: marginal cost curve, water footprint benchmark, soil water balance, crop growth, AquaCrop
Liu, Xin; Wang, Sufen; Xue, Han; Singh, Vijay P
2015-01-01
Modelling crop evapotranspiration (ET) response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1) and summer maize (scenario 2) by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.
Liu, Xin; Wang, Sufen; Xue, Han; Singh, Vijay P.
2015-01-01
Modelling crop evapotranspiration (ET) response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1) and summer maize (scenario 2) by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China. PMID:26439928
NASA Astrophysics Data System (ADS)
Loukas, A.; Tzabiras, J.; Spiliotopoulos, M.; Kokkinos, K.; Fafoutis, C.; Mylopoulos, N.
2015-06-01
The overall objective of this work is the development of a District Information System (DIS) which could be used by stakeholders for the purposes of a district day-to-day water management as well as for planning and strategic decisionmaking. The DIS was developed from a GIS-based modeling approach, which integrates a generic crop model and a hydraulic model of the transport/distribution system, using land use maps generated by Landsat TM imagery. The main sub-objectives are: (i) the development of an operational algorithm to retrieve crop evapotranspiration from remote sensing data, (ii) the development of an information system with friendly user interface for the data base, the crop module and the hydraulic module and (iii) the analysis and validation of management scenarios from model simulations predicting the respective behavior. The Lake Karla watershed is used in this study, but the overall methodology could be used as a basis for future analysis elsewhere. Surface Energy Balance Algorithm for Land (SEBAL) was used to derive monthly actual evapotranspiration (ET) values from Landsat TM imagery. Meteorological data from the archives of the Institute for Research and Technology, Thessaly (I.RE.TE.TH) has also been used. The methodology was developed using high quality Landsat TM images during 2007 growing season. Monthly ET values are used as an input to CROPWAT model. Outputs of CROPWAT model are then used as input for WEAP model. The developed scenario is based on the actual situation of the surface irrigation network of the Local Administration of Land Reclamation (LALR) of Pinios for the year of 2007. The DIS is calibrated with observed data of this year and the district parameterization is conducted based on the actual operation of the network. The operation of the surface irrigation network of Pinios LALR is simulated using Technologismiki Works, while the operation of closed pipe irrigation network of Lake Karla LALR is simulated using Watercad. Four alternative scenarios have been tested with the DIS: reduction of channel losses, alteration of irrigation methods, Introduction of greenhouse cultivation, and operation of the future Lake Karla network. The results of the simulation for the historical period indicate that the water pumped from Pinios LALR is not enough to serve irrigation requirements. The spatial and temporal variation of the unmet and unsatisfied water demand has been estimated. Simulation of the four alternative scenarios indicated that the alteration of irrigation methods scenario mainly increases the efficiency of the irrigation network.
Can climate-effective land management reduce regional warming?
NASA Astrophysics Data System (ADS)
Hirsch, A. L.; Wilhelm, M.; Davin, E. L.; Thiery, W.; Seneviratne, S. I.
2017-02-01
Limiting global warming to well below 2°C is an imminent challenge for humanity. However, even if this global target can be met, some regions are still likely to experience substantial warming relative to others. Using idealized global climate simulations, we examine the potential of land management options in affecting regional climate, with a focus on crop albedo enhancement and irrigation (climate-effective land management). The implementation is performed over all crop regions globally to provide an upper bound. We find that the implementation of both crop albedo enhancement and irrigation can reduce hot temperature extremes by more than 2°C in North America, Eurasia, and India over the 21st century relative to a scenario without management application. The efficacy of crop albedo enhancement scales with the magnitude, where a cooling response exceeding 0.5°C for hot temperature extremes was achieved with a large (i.e., ≥0.08) change in crop albedo. Regional differences were attributed to the surface energy balance response with temperature changes mostly explained by latent heat flux changes for irrigation and net shortwave radiation changes for crop albedo enhancement. However, limitations do exist, where we identify warming over the winter months when climate-effective land management is temporarily suspended. This was associated with persistent cloud cover that enhances longwave warming. It cannot be confirmed if the magnitude of this feedback is reproducible in other climate models. Our results overall demonstrate that regional warming of hot extremes in our climate model can be partially mitigated when using an idealized treatment of climate-effective land management.
NASA Astrophysics Data System (ADS)
Altobelli, F.; Dalla Marta, A.; Cimino, O.; Orlandini, S.; Natali, F.
2014-12-01
In a world where population is rapidly growing and where several planetary boundaries (i.e. climate change, biodiversity loss and nitrogen cycle) have already been crossed, agriculture is called to respond to the needs of food security through a sustainable use of natural resources. In particular, water is one of the main elements of fertility so the agricultural activity, and the whole agro-food chain, is one of the productive sectors more dependent on water resource and it is able to affect, at regional level, its availability for all the other sectors. In this study, we proposed a methodology for assessing the green and blue water footprint of the main Italian crops typical of the different geographical areas (northwest, northeast, center, and south) based on data extracted from Italian Farm Accountancy Data Network (FADN). FADN is an instrument for evaluating the income of agricultural holdings and the impacts of the Common Agricultural Policy. Crops were selected based on incidence of cultivated area on the total arable land of FADN farms net. Among others, the database contains data on irrigation management (irrigated surface, length of irrigation season, volumes of water, etc.), and crop production. Meteorological data series were obtained by a combination of local weather stations and ECAD E-obs spatialized database. Crop water footprints were evaluated against water availability and risk of desertification maps of Italy. Further, we compared the crop water footprints obtained with our methodology with already existing data from similar studies in order to highlight the effects of spatial scale and level of detail of available data.
NASA Astrophysics Data System (ADS)
Ghazouani, Hiba; Provenzano, Giuseppe; Rallo, Giovanni; Mguidiche, Amel; Douh, Boutheina; Boujelben, Abdelhamid
2016-04-01
In Tunisia the amount of water for irrigated agriculture is higher than about 80% of the total resource.The increasing population and the rising food demand, associated to the negative effects of climate change,make it crucial to adopt strategies aiming to improve water use efficiency (WUE). Moreover, the absence of an effective public policy for water management amplifies the imbalance between water supply and its demand. Despite improved irrigation technologies can enhance the efficiency of water distribution systems, to achieve environmental goals it is also necessaryto identify on-farm management strategies accounting for actual crop water requirement. The main objective of the paper was to assess the effects of different on-farm managementstrategies (irrigation scheduling and planting date) on yield and water use efficiency of Potato crop (Solanumtuberosum L.) irrigated with a subsurface drip system, under the semi-arid climate of central Tunisia. Experiments were carried out during three growing seasons (2012, 2014 and 2015) at the High Agronomic Institute of ChottMariem in Sousse, by considering different planting dates and irrigation depths, the latter scheduled according to the climate observed during the season. All the considered treatments received the same pesticide and fertilizer management. Experiments evidenced that the climatic variability characterizing the examined seasons (photoperiod, solar radiation and average temperature) affects considerably the crop phenological stages, and the late sowing shortens the crop cycle.It has also been demonstrated that Leaf Area Index (LAI) and crop yield resulted relatively higher for those treatments receiving larger amounts of seasonal water. Crop yield varied between 16.3 t/ha and 39.1 t/ha, with a trend linearly related to the ratio between the seasonal amount of water supplied (Irrigation, I and Precipitation, P) and the maximum crop evapotranspiration (ETm). The maximum crop yield was in particular obtained for a value of this ratio equal to 1.45. Moreover, when increasing the seasonal pluviometric deficit (P-ETm) and therefore the irrigation depth (I), standard deviations of crop yield tended to decrease, as a consequence ofthe more uniform soil water content in the root zone. In terms of agronomic water use efficiency (AWUE),differences among the investigated treatments varied in a quite narrow range,due to thecombined effects of seasonal precipitation and atmospheric water demand on irrigation depths and crop yield.On the other hand, when considering irrigation water use efficiency (IWUE), more relevant differences between treatments were observed,being the higher values of IWUEgenerally associated to the lower irrigation depths. However, to define the best irrigation management strategy it is necessary, from one side, to consider the availability of water and from the other, to perform aneconomic analysis accounting for the cost of water and the related benefits achievable by the farmer.
Perry, Charles A.
2006-01-01
Data compiled for the High Plains region of Kansas that includes five Groundwater Management Districts (GMDs) were analyzed for trends in irrigation water use, acres irrigated, precipitation, irrigation system types, and irrigated crop types to determine the effects of irrigation practices on water use over time. For the study period 1991 through 2003, precipitation decreased significantly (with 95-percent confidence) in northwestern and west-central Kansas but not in the southwestern and south-central parts of the State. Irrigation water use had no statistically significant trend during this period. There was a good (R= -0.77) relation between average regional precipitation and total GMD irrigation water use. When irrigation water use was adjusted for this relation, there was a positive trend (90-percent confidence level) in the adjusted irrigation water use. Another adjustment to water use was made using the ratio of annual precipitation to 1991-2005 average precipitation, which resulted in a negative trend (95-percent confidence level) in irrigation water use. This demonstrated the contradictory nature of precipitation adjustments to water use, making their utility somewhat suspect. GMD 3 in southwestern Kansas used 63 percent of the total acre-feet of irrigation water within all the GMDs. When all GMDs are considered, the number of irrigated acres for flood and center pivot systems without drop nozzles decreased significantly during the study period. At the same time the number of drop nozzle irrigated acres increased significantly. The number of irrigated acres of water-intensive crops (corn, alfalfa, and soybeans) also increased significantly, whereas the number of less- or non-water-intensive crops (grain sorghum and wheat), and multiple crop type acres decreased. Drop nozzle irrigation systems used approximately 2 percent less water in a year-by-year comparison than center pivot systems and 8 to 11 percent less water than flood irrigation. The best estimator of irrigation water use incorporated total acres irrigated and annual average or March-October regional precipitation. A conclusion that can be drawn from the trend analyses described in this report is that, although irrigation water use for all GMDs showed no statistically significant trend, an apparent increased efficiency of center pivots irrigation systems with drop nozzles has allowed more water-intensive crops to be grown on more irrigated acres.
PERCHLORATE CROP INTERACTIONS VIA CONTAMINATED IRRIGATION WATER
Perchlorate has contaminated water and sods at several locations in the United States. Perchlorate is water soluble, exceedingly mobile in aqueous systems, and can persist for many decades under typical ground- and surface water conditions. Perchlorate is of concern because of un...
Downscaling Surface Temperature Image with TsHARP
USDA-ARS?s Scientific Manuscript database
Daily evapotranspiration (ET) maps would significantly improve assessing crop water requirements, especially in the Texas High Plains (THP) where the supply of irrigation water is limited. Evapotranspireation maps derived from satellite data with daily coverage such as MODIS (Moderate Resolution Ima...
The importance of timing of precipitation for irrigation scheduling
NASA Astrophysics Data System (ADS)
Franz, T.; Hunt, E. D.; Wardlow, B.
2016-12-01
Irrigated agriculture, like rainfed agriculture, continues to serve an important role in the production of cereal crops, with increasing importance in the developing world. Many areas however, including the U.S. High Plains region, are faced with the daunting task of increasing crop production with less water, as groundwater reserves become further depleted. Climate change could further exacerbate limited supplies of groundwater in these regions. Thus, monitoring soil moisture under cereal crops is critical for determining the best irrigation strategies. The results obtained during an eight-year period from an irrigated field in eastern Nebraska demonstrated the importance of the timing of precipitation and soil moisture response for irrigation scheduling. The years with the fewest irrigation applications for both maize and soybeans were not the wettest years during the study period. Paradoxically, the year with the fewest irrigation treatments when soybeans were the common crop at the irrigated field and a nearby rainfed field was in 2006, which had below average growing season precipitation. The year with the most irrigation treatments (2008) when soybeans were also the common crop occurred during one of the wettest growing seasons over the past 30 years at Mead. The primary difference between the below average 2006 growing season and the wet 2008 growing season was that precipitation fell at regular intervals during critical reproductive stages for soybeans in 2006 keeping the soil profile moist. Conversely, the only dry spell of the 2008 growing season occurred during that same critical period, thus necessitating irrigation applications that prevented depletion of soil profile.
Beneduce, Luciano; Gatta, Giuseppe; Bevilacqua, Antonio; Libutti, Angela; Tarantino, Emanuele; Bellucci, Micol; Troiano, Eleonora; Spano, Giuseppe
2017-11-02
In order to evaluate if the reuse of food industry treated wastewater is compatible for irrigation of food crops, without increased health risk, in the present study a cropping system, in which ground water and treated wastewater were used for irrigation of tomato and broccoli, during consecutive crop seasons was monitored. Water, crop environment and final products were monitored for microbial indicators and pathogenic bacteria, by conventional and molecular methods. The microbial quality of the irrigation waters influenced sporadically the presence of microbial indicators in soil. No water sample was found positive for pathogenic bacteria, independently from the source. Salmonella spp. and Listeria monocytogenes were detected in soil samples, independently from the irrigation water source. No pathogen was found to contaminate tomato plants, while Listeria monocytogenes and E. coli O157:H7 were detected on broccoli plant, but when final produce were harvested, no pathogen was detected on edible part. The level of microbial indicators and detection of pathogenic bacteria in field and plant was not dependent upon wastewater used. Our results, suggest that reuse of food industry wastewater for irrigation of agricultural crop can be applied without significant increase of potential health risk related to microbial quality. Copyright © 2017 Elsevier B.V. All rights reserved.
Torak, Lynn J.; Painter, Jaime A.
2011-01-01
Since receiving jurisdiction from the State Legislature in June 2003 to implement the Georgia Agricultural Water Conservation and Metering Program, the Georgia Soil and Water Conservation Commission (Commission) by year-end 2010 installed more than 10,000 annually read water meters and nearly 200 daily reporting, satellite-transmitted, telemetry sites on irrigation systems located primarily in southern Georgia. More than 3,000 annually reported meters and 50 telemetry sites were installed during 2010 alone. The Commission monitored rates and volumes of agricultural irrigation supplied by groundwater, surface-water, and well-to-pond sources to inform water managers on the patterns and amounts of such water use and to determine effective and efficient resource utilization. Summary analyses of 4 complete years of irrigation data collected from annually read water meters in the middle and lower Chattahoochee and Flint River basins during 2007-2010 indicated that groundwater-supplied fields received slightly more irrigation depth per acre than surface-water-supplied fields. Year 2007 yielded the largest disparity between irrigation depth supplied by groundwater and surface-water sources as farmers responded to severe-to-exceptional drought conditions with increased irrigation. Groundwater sources (wells and well-to-pond systems) outnumbered surface-water sources by a factor of five; each groundwater source applied a third more irrigation volume than surface water; and, total irrigation volume from groundwater exceeded that of surface water by a factor of 6.7. Metered irrigation volume indicated a pattern of low-to-high water use from northwest to southeast that could point to relations between agricultural water use, water-resource potential and availability, soil type, and crop patterns. Normalizing metered irrigation-volume data by factoring out irrigated acres allowed irrigation water use to be expressed as an irrigation depth and nearly eliminated the disparity between volumes of applied irrigation derived from groundwater and surface water. Analysis of per-acre irrigation depths provided a commonality for comparing irrigation practices across the entire range of field sizes in southern Georgia and indicated underreporting of irrigated acres for some systems. Well-to-pond systems supplied irrigation at depths similar to groundwater and can be combined with groundwater irrigation data for subsequent analyses. Average irrigation depths during 2010 indicated an increase from average irrigation depths during 2008 and 2009, most likely the result of relatively dry conditions during 2010 compared to conditions in 2008 and 2009. Geostatistical models facilitated estimation of irrigation water use for unmetered systems and demonstrated usefulness in redesigning the telemetry network. Geospatial analysis evaluated the ability of the telemetry network to represent annually reported water-meter data and presented an objective, unbiased method for revising the network.
NASA Astrophysics Data System (ADS)
Campana, P. E.; Zhang, J.; Yao, T.; Melton, F. S.; Yan, J.
2017-12-01
Climate change and drought have severe impacts on the agricultural sector affecting crop yields, water availability, and energy consumption for irrigation. Monitoring, assessing and mitigating the effects of climate change and drought on the agricultural and energy sectors are fundamental challenges that require investigation for water, food, and energy security issues. Using an integrated water-food-energy nexus approach, this study is developing a comprehensive drought management system through integration of real-time drought monitoring with real-time irrigation management. The spatially explicit model developed, GIS-OptiCE, can be used for simulation, multi-criteria optimization and generation of forecasts to support irrigation management. To demonstrate the value of the approach, the model has been applied to one major corn region in Nebraska to study the effects of the 2012 drought on crop yield and irrigation water/energy requirements as compared to a wet year such as 2009. The water-food-energy interrelationships evaluated show that significant water volumes and energy are required to halt the negative effects of drought on the crop yield. The multi-criteria optimization problem applied in this study indicates that the optimal solutions of irrigation do not necessarily correspond to those that would produce the maximum crop yields, depending on both water and economic constraints. In particular, crop pricing forecasts are extremely important to define the optimal irrigation management strategy. The model developed shows great potential in precision agriculture by providing near real-time data products including information on evapotranspiration, irrigation volumes, energy requirements, predicted crop growth, and nutrient requirements.
Irrigation scheduling and controlling crop water use efficiency with Infrared Thermometry
USDA-ARS?s Scientific Manuscript database
Scientific methods for irrigation scheduling include weather, soil and plant-based techniques. Infrared thermometers can be used a non-invasive practice to monitor canopy temperature and better manage irrigation scheduling. This presentation will discuss the theoretical basis for monitoring crop can...
Limited irrigation of corn-based no-till crop rotations in west central Great Plains.
USDA-ARS?s Scientific Manuscript database
Identifying the most profitable crop rotation for an area is a continuous research challenge. The objective of this study was to evaluate 2, 3, and 4 yr. limited irrigation corn (Zea mays L.) based crop rotations for grain yield, available soil water, crop water productivity, and profitability in co...
Litskas, Vassilis D; Aschonitis, Vassilis G; Antonopoulos, Vassilis Z
2010-04-01
A representative agricultural area of 150 ha located in a protected ecosystem (Axios River Delta, Thermaikos Gulf-N. Aegean, Greece) was selected in order to investigate water quality parameters [pH, electrical conductivity (EC(w)), NO(3)-N, NH(4)-N, total phosphorus (TP)] in irrigation and drainage water. In the study area, the cultivated crops are mainly rice, maize, cotton, and fodder. Surface irrigation methods are applied using open channels network, and irrigation water is supplied by Axios River, which is facing pollution problems. The return flow from surface runoff and the surplus of irrigation water are collected to drainage network and disposed to Thermaikos Gulf. A 2-year study (2006-2007) was conducted in order to evaluate the effects of land use and irrigation water management on the drainage water quality. The average pH and NO(3)-N concentration was higher in the irrigation water (8.0 and 1.3 mg/L, respectively) than that in the drainage water (7.6 and 1.0 mg/L, respectively). The average EC(W), NH(4)-N, and TP concentration was higher in the drainage water (1,754 muS/cm, 90.3 microg/L, and 0.2 mg/L, respectively) than that in the irrigation water (477.1 muS/cm, 46.7 microg/L, and 0.1 mg/L, respectively). Average irrigation efficiency was estimated at 47% and 51% in 2006 and 2007 growing seasons (April-October), respectively. The loads of NO(3)-N in both seasons were higher in the irrigation water (35.1 kg/ha in 2006 and 24.9 kg/ha in 2007) than those in the drainage water (8.1 kg/ha in 2006 and 7.6 kg/ha in 2007). The load of TP was higher in the irrigation water in season 2006 (2.8 kg/ha) than that in the drainage water (1.1 kg/ha). Total phosphorus load in 2007 was equal in irrigation and drainage water (1.2 kg/ha). Wetland conditions, due to rice irrigation regime, drainage network characteristics, and the crop distribution in the study area, affect the drainage water ending in the protected ecosystem of Thermaikos Gulf.
Use of thermal and visible imagery for estimating crop water status of irrigated grapevine.
Möller, M; Alchanatis, V; Cohen, Y; Meron, M; Tsipris, J; Naor, A; Ostrovsky, V; Sprintsin, M; Cohen, S
2007-01-01
Achieving high quality wine grapes depends on the ability to maintain mild to moderate levels of water stress in the crop during the growing season. This study investigates the use of thermal imaging for monitoring water stress. Experiments were conducted on a wine-grape (Vitis vinifera cv. Merlot) vineyard in northern Israel. Irrigation treatments included mild, moderate, and severe stress. Thermal and visible (RGB) images of the crop were taken on four days at midday with a FLIR thermal imaging system and a digital camera, respectively, both mounted on a truck-crane 15 m above the canopy. Aluminium crosses were used to match visible and thermal images in post-processing and an artificial wet surface was used to estimate the reference wet temperature (T(wet)). Monitored crop parameters included stem water potential (Psi(stem)), leaf conductance (g(L)), and leaf area index (LAI). Meteorological parameters were measured at 2 m height. CWSI was highly correlated with g(L) and moderately correlated with Psi(stem). The CWSI-g(L) relationship was very stable throughout the season, but for that of CWSI-Psi(stem) both intercept and slope varied considerably. The latter presumably reflects the non-direct nature of the physiological relationship between CWSI and Psi(stem). The highest R(2) for the CWSI to g(L) relationship, 0.91 (n=12), was obtained when CWSI was computed using temperatures from the centre of the canopy, T(wet) from the artificial wet surface, and reference dry temperature from air temperature plus 5 degrees C. Using T(wet) calculated from the inverted Penman-Monteith equation and estimated from an artificially wetted part of the canopy also yielded crop water-stress estimates highly correlated with g(L) (R(2)=0.89 and 0.82, respectively), while a crop water-stress index using 'theoretical' reference temperatures computed from climate data showed significant deviations in the late season. Parameter variability and robustness of the different CWSI estimates are discussed. Future research should aim at developing thermal imaging into an irrigation scheduling tool applicable to different crops.
NASA Astrophysics Data System (ADS)
H. de C. Teixeira, Antônio; Sherer-Warren, Morris; Lopes, Hélio L.; Hernandez, Fernando B. T.; Andrade, Ricardo G.; Neale, Christopher M. U.
2013-10-01
In the semi-arid areas of Petrolina municipality, Northeast Brazil, irrigated agriculture has replaced the natural vegetation, being important the quantification of the energy exchanges between the plants and the low atmosphere. MODIS satellite images and agro-meteorological data for the years of 2010 and 2011 were used together, for modelling the energy balance components under these conditions. Surface albedo (α0), NDVI and surface temperature (T0) were the remote sensing parameters necessary to calculate the latent heat flux (λE) and the surface resistance to evapotranspiration (rs) on a large scale. The daily net radiation (Rn) was retrieved from α0, air temperature (Ta) and transmissivity (τsw), allowing the quantification of the sensible heat flux (H) by residual in the energy balance. With threshold values for rs, it was possible to do a simplified vegetation classification. The incident solar radiation (RS↓) partitioned as Rn ranged from 0.40 to 0.51, corresponding respectively to periods after the rainy season and the driest conditions of the year, with the differences between irrigated crops and natural ecosystem not significant. Considering all periods along the year the averaged fractions of Rn partitioned as H, were 31 and 78%, for irrigated crops and natural vegetation, respectively, while as λE the corresponding ratios were 69 and 22%. It was observed heat advection from the dry areas to irrigated plots, with λE exceeding Rn by 9% during the coldest periods. The models tested here can be used for monitoring the energy exchanges in agro-ecosystems under conditions of land use and climate changes.
Status and migration of irrigation in the USA
USDA-ARS?s Scientific Manuscript database
Irrigated agriculture produces 49% of crop market value on 18% of cropped lands in the USA. Irrigation is essential to the most highly productive, intensely managed, and internationally competitive sectors of our agricultural economy, which play a key role in meeting growing global food, fiber, and ...
Consumptive Water Use and Crop Coefficients of Irrigated Sunflower
USDA-ARS?s Scientific Manuscript database
In semi-arid environments, the use of irrigation is necessary for sunflower production to reach its maximum potential. The aim of this study was to quantify the consumptive water use and crop coefficients of irrigated sunflower (Helianthus annuus L.) without soil water limitations during two growing...
ERIC Educational Resources Information Center
Shea, Kevin P.
1975-01-01
A new means of irrigation, called the drip or trickle system, has been proven more efficient and less wasteful than the current system of flood irrigation. As a result of this drip system, fertilizer-use efficiency is improved and crop yield, though never decreased, is sometimes increased in some crops. (MA)
Probabilistic Description of the Hydrologic Risk in Agriculture
NASA Astrophysics Data System (ADS)
Vico, G.; Porporato, A. M.
2011-12-01
Supplemental irrigation represents one of the main strategies to mitigate the effects of climatic variability on agroecosystems productivity and profitability, at the expenses of increasing water requirements for irrigation purposes. Optimizing water allocation for crop yield preservation and sustainable development needs to account for hydro-climatic variability, which is by far the main source of uncertainty affecting crop yields and irrigation water requirements. In this contribution, a widely applicable probabilistic framework is proposed to quantitatively define the hydrologic risk of yield reduction for both rainfed and irrigated agriculture. The occurrence of rainfall events and irrigation applications are linked probabilistically to crop development during the growing season. Based on these linkages, long-term and real-time yield reduction risk indices are defined as a function of climate, soil and crop parameters, as well as irrigation strategy. The former risk index is suitable for long-term irrigation strategy assessment and investment planning, while the latter risk index provides a rigorous probabilistic quantification of the emergence of drought conditions during a single growing season. This probabilistic framework allows also assessing the impact of limited water availability on crop yield, thus guiding the optimal allocation of water resources for human and environmental needs. Our approach employs relatively few parameters and is thus easily and broadly applicable to different crops and sites, under current and future climate scenarios, thus facilitating the assessment of the impact of increasingly frequent water shortages on agricultural productivity, profitability, and sustainability.
NASA Astrophysics Data System (ADS)
Dogaru, Diana
2016-04-01
Improved water use efficiency in agriculture is a key issue in terms of sustainable management and consumption of water resources in the context of peoples' increasing food demands and preferences, economic growth and agricultural adaptation options to climate variability and change. Crop Water Productivity (CWP), defined as the ratio of yield (or value of harvested crop) to actual evapotranspiration or as the ratio of yield (or value of harvested crop) to volume of supplied irrigation water (Molden et al., 1998), is a useful indicator in the evaluation of water use efficiency and ultimately of cropland management, particularly in the case of regions affected by or prone to drought and where irrigation application is essential for achieving expected productions. The present study investigates the productivity of water in winter wheat and maize cropping systems in the Romanian Plain (49 594 sq. km), an important agricultural region in the southern part of the country which is increasingly affected by drought and dry spells (Sandu and Mateescu, 2014). The scope of the analysis is to assess the gains and losses in CWP for the two crops, by considering increased irrigated cropland and improved fertilization, these being the most common measures potentially and already implemented by the farmers. In order to capture the effects of such measures on agricultural water use, the GIS-based EPIC crop-growth model (GEPIC) (Williams et al., 1989; Liu, 2009) was employed to simulate yields, seasonal evapotranspiration from crops and volume of irrigation water in the Romanian Plain for the 2002 - 2013 interval with focus on 2007 and 2010, two representative years for dry and wet periods, respectively. The GEPIC model operates on a daily time step, while the geospatial input datasets for this analysis (e.g. climate data, soil classes and soil parameters, land use) were harmonized at 1km resolution grid cell. The sources of the spatial data are mainly the national profile agencies/institutes, providing the data at fine resolutions. The increased irrigated area was accounted according to the reported increased percentages of the irrigated area out of the total area equipped for irrigation, as an expected outcome of public irrigation systems rehabilitation schemes (MADR, 2011), while the optimum Nitrogen fertilizer rates for wheat and maize were established according to several field experiments made on irrigated and rain-fed wheat and maize plots in south Romania (Hera and Borlan, 1980). The effects of such farming measures on yields were compared to a baseline condition given by actual irrigated area and fertilization rates. The preliminary results show that potential gains in CWP could be obtained through improved fertilizer management and water allocation in winter wheat cropping systems, particularly in the dry periods, while in maize cropping systems CWP is more sensitive to water than to optimum fertilization rates. Irrigation water supply increases the stability of yields in both cropping systems, although regional differences can be observed across the study area, thus augmenting the relevance and the need for investigations on sustainable use of irrigation water in Romania. As such, this study could represent an information base for further analyses on yield potential under current and future climatic conditions, on impacts of land use patterns and farming practices on crop production in Romania, etc. Keywords: agricultural water use, crop water productivity, irrigation water, GEPIC, Romania References: Molden, D.J., Sakthivadivel, R., Perry, C.J., de Fraiture, C., Kloezen, W.H. (1998). Indicators for comparing performance of irrigated agricultural systems, Research Report 20, IWMI: Colombo, Sri Lanka. Sandu, I., Mateescu E. (2014). Current and prospective climate changes in Romania (in Romanian), in vol. Climate change: a major challenge for research in agriculture (ed. Saulescu, N.), Romanian Academy Publishing House, 17-36. Williams, J.R., Jones, C.A., Kiniry, J.R., Spanel, D.A. (1989). The EPIC crop growth model. Trans. ASAE 32 (2), 497-511. Liu, J. (2009). A GIS-based tool for modelling large-scale crop-water relations, Environmental Modelling & Software, 24, 411-422. MADR (Ministry of Agriculture and Rural Development), (2011). Rehabilitation and reform in the irrigation sector. Strategy of investment in the irrigation sector (in Romanian), Fidman Merk at., Bucharest, http://old.madr.ro/pages/strategie/strategie-investitii-irigatii.pdf. Hera, C., Borlan, Z. (1980). Guide for fertilization planning (in Romanian), 2nd edition, CERES Publishing House, Bucharest, Romania, 341p.
Coupled Crop/Hydrology Model to Estimate Expanded Irrigation Impact on Water Resources
NASA Astrophysics Data System (ADS)
Handyside, C. T.; Cruise, J.
2017-12-01
A coupled agricultural and hydrologic systems model is used to examine the environmental impact of irrigation in the Southeast. A gridded crop model for the Southeast is used to determine regional irrigation demand. This irrigation demand is used in a regional hydrologic model to determine the hydrologic impact of irrigation. For the Southeast to maintain/expand irrigated agricultural production and provide adaptation to climate change and climate variability it will require integrated agricultural and hydrologic system models that can calculate irrigation demand and the impact of the this demand on the river hydrology. These integrated models can be used as (1) historical tools to examine vulnerability of expanded irrigation to past climate extremes (2) future tools to examine the sustainability of expanded irrigation under future climate scenarios and (3) a real-time tool to allow dynamic water resource management. Such tools are necessary to assure stakeholders and the public that irrigation can be carried out in a sustainable manner. The system tools to be discussed include a gridded version of the crop modeling system (DSSAT). The gridded model is referred to as GriDSSAT. The irrigation demand from GriDSSAT is coupled to a regional hydrologic model developed by the Eastern Forest Environmental Threat Assessment Center of the USDA Forest Service) (WaSSI). The crop model provides the dynamic irrigation demand which is a function of the weather. The hydrologic model includes all other competing uses of water. Examples of use the crop model coupled with the hydrologic model include historical analyses which show the change in hydrology as additional acres of irrigated land are added to water sheds. The first order change in hydrology is computed in terms of changes in the Water Availability Stress Index (WASSI) which is the ratio of water demand (irrigation, public water supply, industrial use, etc.) and water availability from the hydrologic model. Also, statistics such as the number of times certain WASSI thresholds are exceeded are calculated to show the impact of expanded irrigation during times of hydrologic drought and the coincident use of water by other sectors. Also, integrated downstream impacts of irrigation are also calculated through changes in flows through the whole river systems.
Testing an Irrigation Decision Support Tool for California Specialty Crops
NASA Astrophysics Data System (ADS)
Johnson, L.; Cahn, M.; Benzen, S.; Zaragoza, I.; Murphy, L.; Melton, F. S.; Martin, F.; Quackenbush, A.; Lockhart, T.
2015-12-01
Estimation of crop evapotranspiration supports efficiency of irrigation water management, which in turn can mitigate nitrate leaching, groundwater depletion, and provide energy savings. Past research in California and elsewhere has revealed strong relationships between photosynthetically active vegetation fraction (Fc) and crop evapotranspiration (ETc). Additional research has shown the potential of monitoring Fc by satellite remote sensing. The U.C. Cooperative Extension developed and operates CropManage (CM) as on-line database irrigation (and nitrogen) scheduling tool. CM accounts for the rapid growth and typically brief cycle of cool-season vegetables, where Fc and fraction of reference ET can change daily during canopy development. The model automates crop water requirement calculations based on reference ET data collected by California Dept. Water Resources. Empirically-derived equations are used to estimate daily Fc time-series for a given crop type primarily as a function of planting date and expected harvest date. An application programming interface (API) is under development to provide a check on modeled Fc of current crops and facilitate CM expansion to new crops. The API will enable CM to extract field scale Fc observations from NASA's Satellite Irrigation Management Support (SIMS). SIMS is mainly Landsat based and currently monitors Fc over about 8 million irrigation acres statewide, with potential for adding data from ESA/Sentinel for improved temporal resolution. In the current study, a replicated irrigation trial was performed on romaine lettuce at the USDA Agricultural Research Station in Salinas, CA. CropManage recommendations were used to guide water treatments by drip irrigation at 50%, 75%, 100% ETc replacement levels, with an added treatment at 150% ET representing grower standard practice. Experimental results indicate that yields from the 100% and 150% treatments were not significantly different and were in-line with industry average, while yields from the 75% and 50% treatments were significantly lower. Additional results will be presented with respect to a subsequent cabbage trial harvested October 2015.
NASA Astrophysics Data System (ADS)
Clay, J.; Kent, E. R.; Leinfelder-Miles, M.; Paw U, K. T.; Little, C.; Lambert, J. J.
2017-12-01
Evapotranspiration and CO2 exchange was measured in five alfalfa fields in the Sacramento-San Joaquin River Delta region from 2016 to 2017 using eddy covariance and surface renewal methods. Seasonal changes of evapotranspiration and CO2 fluxes were compared between 2016, a drought year, and 2017, a high rainfall year. Additionally, changes in evapotranspiration and CO2 flux were investigated across various agronomic considerations, such as irrigation methods (border-check flood and sub-surface), stand life, and herbicide programs. Components of the energy balance, including net radiation, latent heat, ground heat flux, and sensible heat, were evaluated considering correlations to wind speed measured by three sonic anemometers, irrigation frequency, and crop cutting cycle. Comparisons between two different types of radiometers were also carried out. Under drought conditions, we observed higher amounts of evapotranspiration in a field having a stand life of less than two years of age compared to older stands, and in a sub-surface irrigated field compared to flood irrigated fields.
USDA-ARS?s Scientific Manuscript database
Water shortages are responsible for the greatest crop losses around the world and are expected to worsen. In arid areas where agriculture is dependent on irrigation, various forms of deficit irrigation management have been suggested to optimize crop yields for available soil water. The relationshi...
Sorghum response to foliar application of phosphorus and potassium with saline water irrigation
USDA-ARS?s Scientific Manuscript database
Increasing demand for fresh water resources for urban and industrial uses is leading to limited availability of better quality water for crop irrigation. Therefore, crop response to poor quality irrigation water (ex: saline water), and strategies to mitigate the negative effects of poor quality irri...
Infrared thermometry for deficit irrigation of peach trees
USDA-ARS?s Scientific Manuscript database
Water shortage has been a major concern for crop production in the western states of the USA and other arid regions in the world. Deficit irrigation can be used in some cropping systems as a potential water saving strategy to alleviate water shortage, however, the margin of error in irrigation manag...
Performance of a wireless sensor network for crop monitoring and irrigation control
USDA-ARS?s Scientific Manuscript database
Robust automatic irrigation scheduling has been demonstrated using wired sensors and sensor network systems with subsurface drip and moving irrigation systems. However, there are limited studies that report on crop yield and water use efficiency resulting from the use of wireless networks to automat...
Optimizing ET-based irrigation scheduling for wheat and maize with water constraints
USDA-ARS?s Scientific Manuscript database
Deficit irrigation is proved to increase crop water use efficiency (WUE) in water limited areas, but effective irrigation required better understanding of crop responses to water stress intensity and timing. In this study, the Root Zone Water Quality Model (RZWQM) was first calibrated and validated ...
Optimization of irrigation water in stone fruit and table grapes
NASA Astrophysics Data System (ADS)
de la Rosa, Jose Mª; Castillo, Cristina; Temnani, Abdel; Pérez-Pastor, Alejandro
2017-04-01
In water scarcity areas, it must be highlighted that the maximum productions of the crops do not necessarily imply maximum profitability. Therefore, during the last years a special interest in the development of deficit irrigation strategies based on significant reductions of the seasonal ET without affecting production or quality has been observed. The strategies of regulated deficit irrigation (RDI) are based on the reduction of water supply during non critical periods, the covering of water needs during critical periods and maximizing, at the same time, the production by unit of applied water. The main objective of this experiment was to implement, demonstrate and disseminate a sustainable irrigation strategy based on deficit irrigation to promote its large scale acceptance and use in woody crops in Mediterranean agroecosystems, characterized by water scarcity, without affecting the quality standards demanded by exportation markets. Five demonstration plots were established in representative crops of the irrigating community of Campotejar (Murcia, Spain): i) Peach trees, cv. catherina in the "Periquitos" farm; ii) Apricot trees, cv. "Red Carlet" in "La Hoya del Fenazar" farm; iii) Nectarine trees, cv. Viowhite in "Agrícola Don Fernando" farm; iv) Table grape, cv "Crimson Seedless" in "La Hornera" farm; and v) Paraguayan cv. carioca in "The Hornera" farm. In each demonstration plot, at least two irrigation treatments were established: i) Control (CTL), irrigated to ensure non-limiting water conditions (120% of crop evapotranspiration) and ii) Regulated deficit irrigation (RDI) irrigated as CTL during critical periods and decreasing irrigation in non-critical periods. The plant water status indicators evaluated were midday stem water potential and Trunk Diameter Fluctuation derived indices: maximum daily shrinkage (MDS) and trunk daily growth rate (TGR); vegetative growth of the different crops from trunk diameter and pruning dry weight, fruit growth and fruit fresh weight, yield and quality of the harvest were also measured. The irrigation applied in CTL during the 2015-16 was 6770, 7691, 6673, 6774 and 7020 m3 ha-1 year-1 while the decrease in irrigation in RDIs was 28, 40, 12, 34 and 25% for nectarine, peach, apricot, paraguayan and table grapes, respectively. The plant water status indicators used were sensitive to water deficit and showed moderate water stress in RDI. The water deficit affected, to a greater or lesser extent, the vegetative growth of the crop. On the other hand, the yield and fruit quality parameters (size, firmness, total soluble solids, acidity and maturity index) at harvest were not affected by the deficit irrigation. In this way, the water use efficiency increased significantly in RDI treatments. From the information obtained in the demonstration plots irrigation recommendations were made to the farmers of the irrigation community through the project web page. Farmers in the irrigation community are using this information to manage irrigation on their farms, thus improving the profitability of their crops. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).
NASA Astrophysics Data System (ADS)
Sishodia, Rajendra P.; Shukla, Sanjay; Graham, Wendy D.; Wani, Suhas P.; Jones, James W.; Heaney, James
2017-12-01
Effects of future expansion/intensification of irrigated agriculture on groundwater and surface water levels and availability in a semi-arid watershed were evaluated using an integrated hydrologic model (MIKE SHE/MIKE 11) in conjunction with biophysical measurements. Improved water use efficiency, water storage, and energy policy options were evaluated for their ability to sustain the future (2035) increased groundwater withdrawals. Three future withdrawal scenarios (low = 20, medium = 30, high = 50 wells/100 km2/year) based on the historical rate of growth of irrigation wells were formulated. While well drying from falling groundwater levels was limited to drought and consecutive below average rainfall years, under the current (2015) withdrawals, significant increases in frequency and duration (17-97 days/year) of well drying along with 13-26% (19-37 mm) reductions in surface flows were predicted under the future withdrawals. Higher (27-108%) energy demands of existing irrigation pumps due to declining groundwater levels and reduced hydroelectric generation due to decreased surface flows would create a vicious water-food-energy nexus in the future. Crop failure, one of the main causes of farmers' emotional distress and death in the region, is predicted to exacerbate under the future withdrawal scenarios. Shift to negative net recharge (-63 mm) and early and prolonged drying of wells under the high scenario will reduce the groundwater availability and negatively affect crop production in more than 60% and 90% of cropped areas in the Rabi (November-February) and summer (March-May) seasons, respectively during a drought year. Individual and combined demand (drip irrigation and reduced farm electricity subsidy) and supply (water storage) management options improved groundwater levels and reduced well drying by 55-97 days/year compared to business-as-usual management under the high scenario. The combined management (50% drip conversion, 50% reduction in subsidy, and enhanced water storage) mitigated well drying even during drought and consecutive below average rainfall years under the high scenario. A conservative economic evaluation for management options under the high scenario showed increases in crop production and per farmer annual profits by 987-1397 during a drought year (average household income = 1520/year). A scale-up of results showed that diverting 50% state power subsidy (6 billion for 3-6 years) can almost entirely fund the conversion to drip irrigation (4.2 billion) and water storage structures (2.9 billion) and help meet the water supply demand of a 50% increase in irrigated area under the high scenario. Converting flood to drip irrigation in 50% of irrigated area under the high scenario can reduce the electric energy consumption (7 × 106Mwh/year) and carbon footprint (6000 Mt/year) of groundwater irrigation by 24% in the state. Management options considered can potentially create a sustainable water-food-energy nexus in the larger semi-arid hard rock region. Reducing the power subsidy will require a strong political will since it has been used as a tool to win the elections in India. Considering future agricultural intensification, timely interventions are needed to ensure the livelihood and well-being of millions of small- and medium-scale farmers that rely on low storage, hard rock aquifers in the semi-arid regions of the world.
NASA Astrophysics Data System (ADS)
Li, Y.; Kinzelbach, W.; Zhou, J.; Cheng, G. D.; Li, X.
2012-05-01
The hydrologic model HYDRUS-1-D and the crop growth model WOFOST are coupled to efficiently manage water resources in agriculture and improve the prediction of crop production. The results of the coupled model are validated by experimental studies of irrigated-maize done in the middle reaches of northwest China's Heihe River, a semi-arid to arid region. Good agreement is achieved between the simulated evapotranspiration, soil moisture and crop production and their respective field measurements made under current maize irrigation and fertilization. Based on the calibrated model, the scenario analysis reveals that the most optimal amount of irrigation is 500-600 mm in this region. However, for regions without detailed observation, the results of the numerical simulation can be unreliable for irrigation decision making owing to the shortage of calibrated model boundary conditions and parameters. So, we develop a method of combining model ensemble simulations and uncertainty/sensitivity analysis to speculate the probability of crop production. In our studies, the uncertainty analysis is used to reveal the risk of facing a loss of crop production as irrigation decreases. The global sensitivity analysis is used to test the coupled model and further quantitatively analyse the impact of the uncertainty of coupled model parameters and environmental scenarios on crop production. This method can be used for estimation in regions with no or reduced data availability.
NASA Astrophysics Data System (ADS)
Medellin-Azuara, J.; Morande, J. A.; Jin, Y.; Chen, Y.; Paw U, K. T.; Viers, J. H.
2016-12-01
Traditional methods for estimating consumptive water use as evapotranspiration (ET) for agriculture in areas with water limitations such as California have always been a challenge for farmers, water managers, researchers and government agencies. Direct measurement of evapotranspiration (ET) and crop water stress in agriculture can be a cumbersome and costly task. Furthermore, spatial variability of applied water and irrigation and stress level in crops, due to inherent heterogeneity in soil conditions, topography, management practices, and lack of uniformity in water applications may affect estimates water use efficiency and water balances. This situation difficult long-term management of agroecosystems. This paper presents a case study for various areas in California's Central Valley using Unmanned Aerial Vehicles (UAVs) for a late portion of the 2016 irrigation season These estimates are compared those obtained by direct measurement (from previously deployed stations), and energy balance approaches with remotely sensed data in a selection of field crop parcels. This research improves information on water use and site conditions in agriculture by enhancing remote sensing-based estimations through the use of higher resolution multi-spectral and thermal imagery captured by UAV. We assess whether more frequent information at higher spatial resolution from UAVs can improve estimations of overall ET through energy balance and imagery. Stress levels and ET are characterized spatially to examine irrigation practices and their performance to improve water use in the agroecosystem. Ground based data such as air and crop temperature and stem water potential is collected to validate UAV aerial measurements. Preliminary results show the potential of UAV technology to improve timing, resolution and accuracy in the ET estimation and assessment of crop stress at a farm scales. Side to side comparison with ground level stations employing surface renewal, eddy covariance and energy balance provides a testbed to improve understanding of consumptive use and crop water management in water scarce irrigated agriculture regions. Keywords. California Central Valley, Agricultural Water Use, Remote Sensing, Energy Balance, Evapotranspiration, Water management,
Xue, Jingyuan; Huo, Zailin; Wang, Fengxin; Kang, Shaozhong; Huang, Guanhua
2018-04-01
Water scarcity and salt stress are two main limitations for agricultural production. Groundwater evapotranspiration (ET g ) with upward salt movement plays an important role in crop water use and water productivity in arid regions, and it can compensate the impact of deficit irrigation on crop production. Thus, comprehensive impacts of shallow groundwater and deficit irrigation on crop water use results in an improvement of irrigation water productivity (IWP). However, it is difficult to quantify the effects of groundwater and deficit irrigation on IWP. In this study, we built an IWP evaluation model coupled with a water and salt balance model and a crop yield estimation model. As a valuable tool of IWP simulation, the calibrated model was used to investigate the coupling response of sunflower IWP to irrigation water depths (IWDs), groundwater table depth (GTDs) and groundwater salinities (GSs). A total of 210 scenarios were run in which five irrigation water depths (IWDs) and seven groundwater table depths (GTDs) and six groundwater salinities (GSs) were used. Results indicate that increasing GS clearly increases the negative effect on a crop's actual evapotranspiration (ET a ) as salt accumulation in root zone. When GS is low (0.5-1g/L), increasing GTD produces more positive effect than negative effect. In regard to relatively high GS (2-5g/L), the negative effect of shallow-saline groundwater reaches a maximum at 2m GTD. Additionally, the salt concentration in the root zone maximizes its value at 2.0m GTD. In most cases, increasing GTD and GS reduces the benefits of irrigation water and IWP. The IWP increases with decreasing irrigation water. Overall, in arid regions, capillary rise of shallow groundwater can compensate for the lack of irrigation water and improve IWP. By improving irrigation schedules and taking advantages of shallow saline groundwater, we can obtain higher IWP. Copyright © 2017 Elsevier B.V. All rights reserved.
Influence of different operating conditions on irrigation uniformity with microperforated tapes
NASA Astrophysics Data System (ADS)
Moreno Pizani, María Alejandra; Jesús Farías Ramírez, Asdrúbal
2013-04-01
Irrigated agriculture is a safe alternative to meet the growing demand for food. Numerous studies show that proper management of localized irrigation can increase crop yields and reduce soil salinization. Therefore, periodic field systems irrigation assessments are needed in order to optimize the use efficiency of irrigation water, as well as, to increase the agricultural area covered by the same amount of water and to reduce the environmental impact. It was assessed the behavior of micro perforated tapes under different operating conditions, crops and regions of Venezuela. Evaluations were made on irrigated areas using Santeno ® Type I tape with the following crops: Banana (Musa sp), lettuce (Lactuca sativa L.), carrot (Daucus carota L) and forage sugar cane (Saccharum officinarum). In the other hand, Santeno ® Type II tape was used with papaya (Carica papaya L.) and melon (Cucumis melo L.) crops (the last crop using inverted irrigation tape). The procedures used for sampling and determining the uniformity indices of the system were performed using a series of adjustments to the methodology proposed by Keller and Karmeli (1975), Deniculi (1980) and De Santa and De Juan (1993), in order to increase the number of observations as a function of irrigation time. The calculated irrigation uniformity indices were as follow: Distribution Coefficient (UD), Uniformity Coefficient (CUC), Coefficient of Variation of Flows (CV) and Statistical Uniformity Coefficient (Us). The indices characterization was made according to Merrian and Keller (1978); Bralts (1986); Pizarro (1990) y ASAE (1996), respectively. The results showed that the irrigation uniformity for the evaluated systems varied from excellent to unacceptable, mainly due to the lack of maintenance and the absent of manometric connectors. Among the findings, it is possible to highlight the need for technical support to farmers, both in the installation, management and maintenance of irrigation systems. In this sense, it is proposed to establish a simple and reliable procedure to evaluate the irrigation uniformity in the field, which should be available for farmers and feasible for researchers.
NASA Astrophysics Data System (ADS)
Chukalla, Abebe D.; Krol, Maarten S.; Hoekstra, Arjen Y.
2017-07-01
Reducing the water footprint (WF) of the process of growing irrigated crops is an indispensable element in water management, particularly in water-scarce areas. To achieve this, information on marginal cost curves (MCCs) that rank management packages according to their cost-effectiveness to reduce the WF need to support the decision making. MCCs enable the estimation of the cost associated with a certain WF reduction target, e.g. towards a given WF permit (expressed in m3 ha-1 per season) or to a certain WF benchmark (expressed in m3 t-1 of crop). This paper aims to develop MCCs for WF reduction for a range of selected cases. AquaCrop, a soil-water-balance and crop-growth model, is used to estimate the effect of different management packages on evapotranspiration and crop yield and thus the WF of crop production. A management package is defined as a specific combination of management practices: irrigation technique (furrow, sprinkler, drip or subsurface drip); irrigation strategy (full or deficit irrigation); and mulching practice (no, organic or synthetic mulching). The annual average cost for each management package is estimated as the annualized capital cost plus the annual costs of maintenance and operations (i.e. costs of water, energy and labour). Different cases are considered, including three crops (maize, tomato and potato); four types of environment (humid in UK, sub-humid in Italy, semi-arid in Spain and arid in Israel); three hydrologic years (wet, normal and dry years) and three soil types (loam, silty clay loam and sandy loam). For each crop, alternative WF reduction pathways were developed, after which the most cost-effective pathway was selected to develop the MCC for WF reduction. When aiming at WF reduction one can best improve the irrigation strategy first, next the mulching practice and finally the irrigation technique. Moving from a full to deficit irrigation strategy is found to be a no-regret measure: it reduces the WF by reducing water consumption at negligible yield reduction while reducing the cost for irrigation water and the associated costs for energy and labour. Next, moving from no to organic mulching has a high cost-effectiveness, reducing the WF significantly at low cost. Finally, changing from sprinkler or furrow to drip or subsurface drip irrigation reduces the WF, but at a significant cost.
Re-Assessing Leaching Requirements for the Salinity Control under New Irrigation Regimes
NASA Astrophysics Data System (ADS)
Wu, Laosheng; Yang, Ting; Šimůnek, Jirka
2017-04-01
Irrigation is essential to sustain agricultural production, but it adds dissolved salts (or salinity) to croplands. Leaching is thus necessary to keep the average rootzone salinity below the plant threshold EC levels in order to sustain crop production. Current leaching requirement (LR) calculation is based on steady-state, one-dimensional (1D), and water balance approaches, which often overestimates the LRs under transient field conditions. While in recent years, surface and sprinkler irrigated fields have been largely converted to drip or micro-spray systems and deficit irrigation has become more popular, currently accepted LRs may not be appropriate for these irrigation systems. Under point or line irrigation sources (e.g., drips or drip-lines), water and salts move both downwards and laterally, which may lead to highly saline areas on the edges of the wetted area. Under such circumstances, processes such as precipitation/dissolution of mineral phases and/or cation exchange may significantly affect the leaching requirement. The overall objective of this research was to use computer simulation models (i.e., Hydrus-2D and UnsatChem) to evaluate LRs under transient conditions and new irrigation regimes. Simulations were carried out using parameters for soils, climate zones, and major crops and their corresponding fertilization practices typical for California to: (1) Assess the effects of salt precipitation/dissolution on the leaching requirement (LR); (2) Evaluate localized water movement on average rootzone salinity and the leaching requirement (LR); (3) Evaluate leaching requirements for soils under deficit irrigation; and (4) Assess the effects of rainfall on the leaching requirement. Information from this research could significantly impact water management practices in irrigated croplands.
COLT: seasonal prediction of crop irrigation needs
NASA Astrophysics Data System (ADS)
Villani, Giulia; Spisni, Andrea; Mariani, Maria Cristina; Pratizzoli, William; Pavan, Valentina; Tomei, Fausto; Botarelli, Lucio; Marletto, Vittorio
2013-04-01
COLT is an operational chain to predict summer (June, July, August) crop irrigation needs in Emilia-Romagna (Northern Italy) at the regional and lower scales. Set up by ARPA-SIMC in 2010, it has been applied since with good results. COLT predicts summer irrigation needs in May, i.e. at the beginning of the irrigation season in Emilia-Romagna. COLT is based on the production of yearly updated land use maps, observed daily weather data, a regional soil map and ensemble probabilistic seasonal weather forecasts obtained from the EUROSIP multi-model operational system and a geographical soil water balance model (CRITERIA). The first step of the operational scheme is the supervised classification of crops through field surveys and a set of multitemporal satellite images acquired during the first months of the growing period. As the identification of all crop species during the satellite working windows is not feasible, they are grouped in six classes: summer field crops (including corn, sorghum, tomato, sugar beet, potato and others), winter crops (wheat, barley, oat, etc.), perennial grasses (alfa-alfa and meadows), rice, vineyards and orchards, on the whole regional plain, covering about 775000 ha. The second step involves the statistical downscaling of the EUROSIP ensemble predictions over Emilia-Romagna and the use of a weather generator to synthetically produce a number (usually 50) replicated meteorological summer daily data series, consistent with the predicted and downscaled summer anomalies of temperature, rainfall and other related indices. During the final step the CRITERIA model computes crop development and soil water balance on the crop classification map using observed meteorological daily data up to the end of May. Afterword forecasts are used up to the end of the summer irrigation season, i.e. August 31st. The statistical distribution projections of summer irrigation needs at the regional and reclamation consortia scale are then issued and disseminated from the ARPA-SIMC web site. Since 2010 forecasts of the crops water irrigation requirements have been computed and compared with the simulated data at the end of the summer with good results. The COLT scheme is able to predict the very large interannual variability of the seasonal crop water needs: in 2010 the summer was rather wet and COLT predicted about 500 Mm3, while in 2011 the median forecast was 850 Mm3, a value considered as normal. The summer of 2012 was exceptionally dry, thus the median COLT forecast was 1077 Mm3, while the value computed with observed summer data reached 1340 Mm3 (+24%). The COLT scheme was also tested in a study area located near Ravenna (570 ha), where actual crop irrigation volumes are measured. The median forecasted irrigation (0.50 Mm3) resulted 14% higher than the observed value for 2011 (0.44 Mm3), mainly due to errors in classification of non irrigated crops as irrigated, and possibly to the water table not being accounted for in the model. COLT looks like a promising approach for assessing, planning and managing water resources in agriculture, and for mitigating the impacts of intense climate anomalies in the agricultural sector.
USDA-ARS?s Scientific Manuscript database
Many landscapes are comprised of a variety of vegetation types with different canopy structure, rooting depth, physiological characteristics, including response to environmental stressors, etc. Even in agricultural regions, different management practices, including crop rotations, irrigation schedu...
USDA-ARS?s Scientific Manuscript database
Thermal-infrared remote sensing of land surface temperature (LST) provides valuable information for quantifying rootzone water availability, evapotranspiration (ET) and crop condition. This paper describes the most recent modifications applied to the robust but relatively simple LST-based energy bal...
PERCHLORATE-CROP INTERACTIONS FROM CONTAMINATED IRRIGATION WATER AND FERTILIZER APPLICATIONS
Perchlorate has contaminated water and soils at several locations in the United States. Perchlorate is water soluble, exceedingly mobile in aqueous systems, and can persist for many decades under typical ground and surface water conditions. Perchlorate is of concern because of un...
Quanqi, Li; Yuhai, Chen; Xunbo, Zhou; Songlie, Yu; Changcheng, Guo
2012-01-01
In north China, double cropping of winter wheat and summer maize is a widely adopted agricultural practice, and irrigation is required to obtain a high yield from winter wheat, which results in rapid aquifer depletion. In this experiment conducted in 2001-2002, 2002-2003, and 2004-2005, we studied the effects of irrigation regimes during specific winter wheat growing stage with winter wheat and summer maize double cropping systems; we measured soil moisture before sowing (SMBS), the photosynthetic active radiation (PAR) capture ratio, grain yield, and the radiation use efficiency (RUE) of summer maize. During the winter wheat growing season, irrigation was applied at the jointing, heading, or milking stage, respectively. The results showed that increased amounts of irrigation and irrigation later in the winter wheat growing season improved SMBS for summer maize. The PAR capture ratio significantly (LSD, P < 0.05) increased with increased SMBS, primarily in the 3 spikes leaves. With improved SMBS, both the grain yield and RUE increased in all the treatments. These results indicate that winter wheat should be irrigated in later stages to achieve reasonable grain yield for both crops. PMID:22654613
Sun, Mei; Huo, Zailin; Zheng, Yanxia; Dai, Xiaoqin; Feng, Shaoyuan; Mao, Xiaomin
2018-02-01
Quantitatively ascertaining and analyzing long-term responses of crop yield and nitrate leaching on varying irrigation and fertilization treatments are focal points for guaranteeing crop yield and reducing nitrogen loss. The calibrated agricultural-hydrological RZWQM2 model was used to explore the long-term (2003-2013) transport processes of water and nitrogen and the nitrate leaching amount into groundwater in summer maize and winter wheat rotation field in typical intensive plant area in the North China Plain, Daxing district of Beijing. Simulation results showed that application rates of irrigation and nitrogen fertilizer have couple effects on crop yields and nitrogen leaching of root zone. When both the irrigation and fertilizer for summer maize and winter wheat were 400mm and 400kgNha -1 , respectively, nitrate leaching into groundwater accounted for 47.9% of application amount of nitrogen fertilizer. When application amount of irrigation is 200mm and fertilization is 200kgNha -1 , NUPE (nitrogen uptake efficiency), NUE (nitrogen use efficiency), NPFP (nitrogen partial factor productivity), and W pi (irrigation water productive efficiency) were in general higher than that under other irrigation and fertilization condition (irrigation from 104-400mm, fertilizer 104-400kgNha -1 ). Irrigation bigger than 200mm could shorten the response time of nitrate leaching in deeper soil layer in different irrigation treatment. Copyright © 2017 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pawlowski, Meghan N.; Crow, Susan E.; Meki, Manyowa N.
Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHGmore » emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO 2), as methane was oxidized and nitrous oxide (N 2O) emission was very low even following fertilization. High N 2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO 2 flux. Furthermore, deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated below ground. In the first two years of cultivation napier grass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield.« less
Pawlowski, Meghan N.; Crow, Susan E.; Meki, Manyowa N.; ...
2017-01-04
Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHGmore » emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO 2), as methane was oxidized and nitrous oxide (N 2O) emission was very low even following fertilization. High N 2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO 2 flux. Furthermore, deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated below ground. In the first two years of cultivation napier grass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield.« less
Desert agricultural terrace systems at EBA Jawa (Jordan) - Layout, water availability and efficiency
NASA Astrophysics Data System (ADS)
Meister, Julia; Krause, Jan; Müller-Neuhof, Bernd; Portillo, Marta; Reimann, Tony; Schütt, Brigitta
2016-04-01
Located in the arid basalt desert of northeastern Jordan, the Early Bronze Age (EBA) settlement of Jawa is by far the largest and best preserved archaeological EBA site in the region. Recent surveys in the close vicinity revealed well-preserved remains of three abandoned agricultural terrace systems. In the presented study these archaeological features are documented by detailed mapping and the analysis of the sediment records in a multi-proxy approach. To study the chronology of the terrace systems optically stimulated luminescence (OSL) is used. In order to evaluate the efficiency of the water management techniques and its impact on harvest yields, a crop simulation model (CropSyst) under today's climatic conditions is applied, simulating crop yields with and without (runoff) irrigation. In order to do so, a runoff time series for each agricultural terrace system and its catchment is generated, applying the SCS runoff curve number method (CN) based on rainfall and soil data. Covering a total area of 38 ha, irrigated terrace agriculture was practiced on slopes, small plateaus, and valleys in the close vicinity of Jawa. Floodwater from nearby wadis or runoff from adjacent slopes was collected and diverted via surface canals. The terraced fields were arranged in cascades, allowing effective water exploitation through a system of risers, canals and spillways. The examined terrace profiles show similar stratigraphic sequences of mixed unstratified fine sediments that are composed of small-scale relocated sediments with local origin. The accumulation of these fines is associated with the construction of agricultural terraces, forcing infiltration and storage of the water within the terraces. Two OSL ages of terrace fills indicate that the construction of these terrace systems started as early as 5300 ± 300 a, which fits well to the beginning of the occupation phase of Jawa at around 3.500 calBC, thus making them to the oldest examples of its kind in the Middle East known to date. The results for simulating yields of different crops and under different irrigation scenarios showed that simulated mean grain yields were greater under supplemental irrigation. Thereby, yields usually increase considerably with increasing catchment size and thus (runoff) irrigation. Moreover, there is a significant decrease of crop failures under irrigation. Overall, these agricultural terrace systems seem to have been very efficient and their construction required a good understanding of the local climate, hydrology, geomorphology & pedology.
Popova, Inna E; Bair, Daniel A; Tate, Kenneth W; Parikh, Sanjai J
2013-07-01
The use of veterinary pharmaceuticals in beef cattle has led to concerns associated with the development of antibiotic resistance in bacteria and endocrine disruption in aquatic organisms. Despite the potential negative consequences, data on the transport and mitigation of pharmaceuticals in grazed watersheds with irrigated pasture are scarce. The objective of this study was to assess the transport of common beef cattle pharmaceuticals (oxytetracycline, chlortetracycline, and ivermectin) via surface runoff and leachate from manure amended to grass-vegetated soil boxes under irrigated pasture conditions. The transport of pharmaceuticals from animal manure in surface runoff and soil leachate was relatively low and appears to be limited by desorption and transport of pharmaceuticals entrained in the manure. In surface runoff, less than 4.2% of applied pharmaceuticals in manure (initial concentration: 0.2 mg kg of manure) was detected after 3 wk of irrigation. Concentrations of pharmaceuticals in surface runoff and leachate never exceeded 0.5 μg L. The major portion of pharmaceuticals (up to 99%) was retained in the manure or in the soil directly beneath the manure application site. Based on the minimal transport of oxytetracycline, chlortetracycline, and ivermectin, the risk of significant transport for these targeted beef cattle pharmaceuticals to surface water and groundwater from manure on irrigated pasture appears to be relatively low. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Development of an irrigation scheduling software based on model predicted crop water stress
USDA-ARS?s Scientific Manuscript database
Modern irrigation scheduling methods are generally based on sensor-monitored soil moisture regimes rather than crop water stress which is difficult to measure in real-time, but can be computed using agricultural system models. In this study, an irrigation scheduling software based on RZWQM2 model pr...
Developing a hybrid solar/wind powered irrigation system for crops in the Great Plains
USDA-ARS?s Scientific Manuscript database
Some small scale irrigation systems (< 2 ha) powered by wind or solar do not require subsidies, but this paper discusses ways to achieve an economical renewable energy powered center pivot irrigation system for crops in the Great Plains. By adding a solar-photovoltaic (PV) array together with a wind...
López-Gálvez, F; Truchado, P; Sánchez, G; Aznar, R; Gil, M I; Allende, A
2016-10-01
To assess the prevalence of enteric viruses in different irrigation water sources and in the irrigated produce, and the possible links with microbiological and physicochemical water characteristics. The prevalence and levels of Escherichia coli, Norovirus (NoV) genogroup I (GI) and II (GII), as well as Hepatitis A virus were assessed in three types of water: surface water (surface-W), reclaimed water subjected to secondary treatment (secondary-W) and reclaimed water subjected to tertiary treatment (tertiary-W), as well as in zucchini irrigated with these irrigation water sources. Chemical oxygen demand (COD), turbidity, total suspended solids, alkalinity and maximum filterable volume (MFV) were also measured in the water. Higher prevalence of NoV in secondary-W (GI 100%, GII 55·6%) and tertiary-W (GI 91·7%, GII 66·7%) compared with surface-W (GI 58·4%, GII 22·2%) was observed. Nov GI showed positive correlation with E. coli (Spearman's correlation coefficient = 0·68, P < 0·01), and with some physicochemical parameters such as COD (0·52, P < 0·01), turbidity (0·52, P < 0·01) and MFV (0·54, P < 0·01). Escherichia coli and enteric viruses were not detected in zucchini. There is a potential risk of contamination of crops with NoV when reclaimed water is used for irrigation. Increase the knowledge on the prevalence of enteric viruses in different irrigation water sources, and its consequences for fresh produce safety. © 2016 The Society for Applied Microbiology.
Silva, N S; Saad, L P; Souza-Campana, D R; Bueno, O C; Morini, M S C
2017-02-01
In many sugarcane plantations in Brazil, the straw is left on the soil after harvesting, and vinasse, a by-product of the production of sugar and ethanol, is used for fertigation. Our goal was to compare ant community composition and species richness in the straw mulch of sugarcane crops with the leaf litter of neighboring forests. We tested the hypothesis that ant communities in the straw mulch of vinasse-irrigated sugarcane crops and in the forest leaf litter were similar, because the combination of straw mulching and vinasse irrigation has a positive effect on soil fauna. Straw mulch and leaf litter were collected from 21 sites and placed in Berlese funnels. In total, 61 species were found in the forest leaf litter, whereas 34 and 28 species were found in the straw mulch of sugarcane fields with and without vinasse, respectively. Ant communities differed between forest and crop fields, but the species in the sugarcane straw mulch were a subset of the species found in the forest leaf litter. Although vinasse is rich in organic matter, it did not increase ant diversity. Seven feeding and/or foraging types were identified and, among the different types, surface-foraging omnivorous ants were the most prevalent in all habitats. Vinasse-irrigated sugarcane straw mulch had more predatory species than mulch from vinasse-free fields, but fewer than forest leaf litter. However, this positive effect of vinasse irrigation should be carefully evaluated because vinasse has negative effects on the environment. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Impacts of crop insurance on water withdrawals for irrigation
NASA Astrophysics Data System (ADS)
Deryugina, Tatyana; Konar, Megan
2017-12-01
Agricultural production remains particularly vulnerable to weather fluctuations and extreme events, such as droughts, floods, and heat waves. Crop insurance is a risk management tool developed to mitigate some of this weather risk and protect farmer income in times of poor production. However, crop insurance may have unintended consequences for water resources sustainability, as the vast majority of freshwater withdrawals go to agriculture. The causal impact of crop insurance on water use in agriculture remains poorly understood. Here, we determine the empirical relationship between crop insurance and irrigation water withdrawals in the United States. Importantly, we use an instrumental variables approach to establish causality. Our methodology exploits a major policy change in the crop insurance system - the 1994 Federal Crop Insurance Reform Act - which imposed crop insurance requirements on farmers. We find that a 1% increase in insured crop acreage leads to a 0.223% increase in irrigation withdrawals, with most coming from groundwater aquifers. We identify farmers growing more groundwater-fed cotton as an important mechanism contributing to increased withdrawals. A 1% increase in insured crop acreage leads to a 0.624% increase in cotton acreage, or 95,602 acres. These results demonstrate that crop insurance causally leads to more irrigation withdrawals. More broadly, this work underscores the importance of determining causality in the water-food nexus as we endeavor to achieve global food security and water resources sustainability.
NASA Astrophysics Data System (ADS)
Wahyuningsih, Retno; Rintis Hadiani, RR; Sobriyah
2017-01-01
Cau irrigation area located in Madiun district, East Java Province, irrigates 1.232 Ha of land which covers Cau primary channel irrigation network, Wungu Secondary channel irrigation network, and Grape secondary channel irrigation network. The problems in Cau irrigation area are limited availability of water especially during the dry season (planting season II and III) and non-compliance to cropping patterns. The evaluation of irrigation system performance of Cau irrigation area needs to be done in order to know how far the irrigation system performance is, especially based on planting productivity aspect. The improvement of irrigation network performance through cropping pattern optimization is based on the increase of water necessity fulfillment (k factor), the realization of planting area and rice productivity. The research method of irrigation system performance is by analyzing the secondary data based on the Regulation of Ministry of Public Work and State Minister for Public Housing Number: 12/PRT/M/2015. The analysis of water necessity fulfillment (k factor) uses Public Work Plan Criteria Method. The performance level of planting productivity aspect in existing condition is 87.10%, alternative 1 is 93.90% dan alternative 2 is 96.90%. It means that the performance of the irrigation network from productivity aspect increases 6.80% for alternative 1 and 9.80% for alternative 2.
Schmid, Wolfgang; Dogural, Emin; Hanson, Randall T.; Kadir, Tariq; Chung, Francis
2011-01-01
Two hydrologic models, MODFLOW with the Farm Process (MF-FMP) and the Integrated Water Flow Model (IWFM), are compared with respect to each model’s capabilities of simulating land-use hydrologic processes, surface-water routing, and groundwater flow. Of major concern among the land-use processes was the consumption of water through evaporation and transpiration by plants. The comparison of MF-FMP and IWFM was conducted and completed using a realistic hypothetical case study. Both models simulate the water demand for water-accounting units resulting from evapotranspiration and inefficiency losses and, for irrigated units, the supply from surface-water deliveries and groundwater pumpage. The MF-FMP simulates reductions in evapotranspiration owing to anoxia and wilting, and separately considers land-use-related evaporation and transpiration; IWFM simulates reductions in evapotranspiration related to the depletion of soil moisture. The models simulate inefficiency losses from precipitation and irrigation water applications to runoff and deep percolation differently. MF-FMP calculates the crop irrigation requirement and total farm delivery requirement, and then subtracts inefficiency losses from runoff and deep percolation. In IWFM, inefficiency losses to surface runoff from irrigation and precipitation are computed and subtracted from the total irrigation and precipitation before the crop irrigation requirement is estimated. Inefficiency losses in terms of deep percolation are computed simultaneously with the crop irrigation requirement. The seepage from streamflow routing also is computed differently and can affect certain hydrologic settings and magnitudes ofstreamflow infiltration. MF-FMP assumes steady-state conditions in the root zone; therefore, changes in soil moisture within the root zone are not calculated. IWFM simulates changes in the root zone in both irrigated and non-irrigated natural vegetation. Changes in soil moisture are more significant for non-irrigated natural vegetation areas than in the irrigated areas. Therefore, to facilitate the comparison of models, the changes in soil moisture are only simulated by IWFM for the natural vegetation areas, and soil-moisture parameters in irrigated regions in IWFM were specified at constant values . The IWFM total simulated changes in soil moisture that are related to natural vegetation areas vary from stress period to stress period but are small over the entire two-year period of simulation. In the hypothetical case study, IWFM simulates more evapotranspiration and return flows and less streamflow infiltration than MF-FMP. This causes more simulated surface-water diversions upstream and less simulated water available to downstream farms in IWFM compared to MF-FMP. The evapotranspiration simulated by the two models is well correlated even though the quantity is different. The different approaches used to simulate soil moisture, evapotranspiration, and inefficient losses yield different results for deep percolation and pumpage. In IWFM, deep percolation is a function of soil moisture; therefore, the constant soil-moisture requirement for irrigated regions, assumed for this comparison, results in a constant deep percolation rate. This led to poor correlation with the variable deep percolation rates simulated in MF-FMP, where the deep percolation rate, a fraction of inefficiency losses from precipitation and irrigation, is a function of quasi-steady state infiltration for each soil type and a function of groundwater head. Similarly, the larger simulated evapotranspiration in IWFM is mainly responsible for larger simulated groundwater pumpage demands and related lower groundwater levels in IWFM compared to MF-FMP. Because of the differences in features between MF-FMP and IWFM, the user may find that for certain hydrologic settings one model is better suited than the other. The performance of MF-FMP and IWFM in this particular hypothetical test case, with a fixed framework composed of common initial and boundary conditions and input parameter values, does not necessarily predict the performance of MF-FMP and IWFM in a real-world situation with variable framework and parameter values. These differences may affect the evaluation of policies, projects, or water-balance analysis for some hydrologic settings. Generally, both models are powerful tools that simulate a connected system of aquifer, stream networks, land surface, root zone, and runoff processes. MF-FMP simulated the hypothetical test case in about 4 minutes compared to about 58 minutes for IWFM.
NASA Astrophysics Data System (ADS)
Wen, Y.
2017-12-01
Combining mulch and irrigation scheduling may lead to an increase of crop yield and water use efficiency (WUE = crop yield/evapotranspiration) with limited irrigation water, especially in arid regions. Based on 2 years' field experiments with ten irrigation-mulching treatments of spring wheat (Triticum aestivum L.) in the Shiyang River Basin Experiment Station in Gansu Province of Northwest China, a simulation-based optimization model for deficit irrigation scheduling of plastic mulching spring wheat was used to analyze an optimal irrigation scheduling for different deficit irrigation scenarios. Results revealed that mulching may increase maximum grain yield without water stress by 0.4-0.6 t ha-1 in different years and WUE by 0.2-0.3 kg m-3 for different irrigation amounts compared with no mulching. Yield of plastic mulching spring wheat was more sensitive to water stress in the early and development growth stages with an increase of cumulative crop water sensitive index (CCWSI) by 42%, and less sensitive to water stress in the mid and late growth stages with a reduction of CCWSI by 24%. For a relative wet year, when irrigation water is only applied once it should be at the mid to end of booting growth stage. Two irrigations should be applied at the beginning of booting and heading growth stages. The irrigation date can be extended to the beginning of jointing and grain formation growth stages with more water available for irrigation. For a normal or a dry year, the first irrigation should be applied 5-8 days earlier than the wet year. The highest WUE of 3.6 kg m-3 was achieved with 180 mm of irrigation applied twice for mulching in a wet year. Combining mulch and an optimal deficit irrigation scheduling is an effective way to increase crop yield and WUE in arid regions.
Greenhouse irrigation control system design based on ZigBee and fuzzy PID technology
NASA Astrophysics Data System (ADS)
Zhou, Bing; Yang, Qiliang; Liu, Kenan; Li, Peiqing; Zhang, Jing; Wang, Qijian
In order to achieve the water demand information accurately detect of the greenhouse crop and its precision irrigation automatic control, this article has designed a set of the irrigated control system based on ZigBee and fuzzy PID technology, which composed by the soil water potential sensor, CC2530F256 wireless microprocessor, IAR Embedded Workbench software development platform. And the time of Irrigation as the output .while the amount of soil water potential and crop growth cycle as the input. The article depended on Greenhouse-grown Jatropha to verify the object, the results show that the system can irrigate timely and appropriately according to the soil water potential and water demend of the different stages of Jatropha growth , which basically meet the design requirements. Therefore, the system has broad application prospects in the amount of greenhouse crop of fine control irrigation.
Simulation and optimization model for irrigation planning and management
NASA Astrophysics Data System (ADS)
Kuo, Sheng-Feng; Liu, Chen-Wuing
2003-10-01
A simulation and optimization model was developed and applied to an irrigated area in Delta, Utah to optimize the economic benefit, simulate the water demand, and search the related crop area percentages with specified water supply and planted area constraints. The user interface model begins with the weather generation submodel, which produces daily weather data, which is based on long-term monthly average and standard deviation data from Delta, Utah. To simulate the daily crop water demand and relative crop yield for seven crops in two command areas, the information provided by this submodel was applied to the on-farm irrigation scheduling submodel. Furthermore, to optimize the project benefit by searching for the best allocation of planted crop areas given the constraints of projected water supply, the results were employed in the genetic algorithm submodel. Optimal planning for the 394·6-ha area of the Delta irrigation project is projected to produce the maximum economic benefit. That is, projected profit equals US$113 826 and projected water demand equals 3·03 × 106 m3. Also, area percentages of crops within UCA#2 command area are 70·1%, 19% and 10·9% for alfalfa, barley and corn, respectively, and within UCA#4 command area are 41·5%, 38·9%, 14·4% and 5·2% for alfalfa, barley, corn and wheat, respectively. As this model can plan irrigation application depths and allocate crop areas for optimal economic benefit, it can thus be applied to many irrigation projects. Copyright
Aerial thermal images to assess irrigation efficiency in 'Vitis vinifera' cv. Albariño
NASA Astrophysics Data System (ADS)
Gonzalez, Xesús Pablo; Fandiño, María; Rey, Benjamín J.; José Cancela, Javier
2017-04-01
Canopy temperature was defined as key data to irrigation management and to detect crop water stress (Jackson, 1982). Recently, temperature camera was installed on board in a Unmanned Aerial Vehicle (UAV), thus heterogeneity within field could be determined. Pereira et al. (2012) have defined the conceptual and terminological study of crop water use indicators, mainly water use efficiency (WUE) and water productivity (WP). Actually, it is crucial achieve higher WP and WUE, where crop yield variability between years must be reduced with the smallest irrigation water, but with a correct management of crop water stress during the season. In this study, Albariño cultivar grapevine, priority in Galicia (Spain) in Designation of Origen 'Rías Baixas', was assessed in relation to water productivity index, focus on irrigation treatments aspects, during 2016. Albariño vineyard was planted in 1996 on 110-Richter at a spacing of 3 × 2 m (1667 vines ha-1) (41°57 6 N, 8°49 26 W, elevation 101 m). Vines were trained to a vertical trellis system on a Guyot oriented in the East-West direction. Three irrigation treatments were applied: irrigation from budburst to maturation (T1), from flowering to maturation (T2), and from veraison to maturation (T3), moreover a rain-fed treatment was implemented. All WP index was referred to farm yield level (kg ha-1); where the denominator applied to WP TWUfarm, introduced rainfall and irrigation depth; to WP Irrig, only irrigation depth applied; was used. Moreover, crop water stress index (CWSI) was used to determine homogenize areas within experimental plot, using an UAV with a thermal camera (ThermoMAP, senseFly, SW) to achieve a final map with 14 cm per pixel resolution. During August 11th, at the end of veraison, camera was installed in an 'eBee Ag' UAV (senseFly, SW) with a median flight altitude of 75 m over ground level. Yield per hectare were recorded and total irrigation depth per treatment during the growing season from March to harvest. Preliminary results have showed that CWSI is useful to determine heterogeneity areas within field, concretely areas with identic irrigation treatments were grouped in a similar range, a good correlation was achieved with steam water potential measured in verasion during the flight. This aspect permit establishes a tool to manage irrigation with efficiency, during the growing season, using thermal data and CWSI. Finally, WP were higher in rain-fed than irrigated treatments, where T3 treatment showed higher WP Irrig, than T1 and T2 treatments. A new step Economic aspects should be studied, taken into account benefit crop yield, and cost of pumping irrigation water. References: Jackson, RD (1982). Canopy temperature and crop water stress. Advances in irrigation, 1:43-85 Pereira LS, Cordery I, Iacovides I (2012). Improved indicators of water use performance and productivity for sustainable water conservation and saving. Agricultural Water Management, 108:39-51
NASA Astrophysics Data System (ADS)
Castellanos Serrano, María Teresa; Requejo Mariscal, María Isabel; Cartagena Causapé, María Carmen; Arce Martínez, Augusto; Ribas Elcorobarrutia, Francisco; Jesús Cabello Cabello, María; María Tarquis Alfonso, Ana
2016-04-01
The concept of "water footprint" (WF) was introduced as an indicator for the total volume of direct and indirect freshwater used, consumed and/or polluted [1]. The WF distinguishes between blue water (volume of surface and groundwater consumed), green water (rain-water consumed), and grey water (volume of freshwater that is required to assimilate the load of pollutants based on existing ambient water quality standards). In semiarid scenarios with low water quality, where the irrigation is necessary to maintain production, green WF is zero because the effective rainfall is negligible. As well as blue WF includes: i) extra consumption or irrigation water that the farmer has to apply to compensate the fail of uniformity on discharge of drips, ii) percolation out of control or salts leaching, which depends on the salt tolerance of the crop, soil and quality of irrigation water, to ensure the fruit yield. The major concern is grey WF, because the irrigation and nitrogen dose have to be adjusted to the crop needs in order to minimize nitrate pollution. This study is focused in assessment mineral and organic fertilization on grey WF in a fertirrigated melon crop under semiarid conditions, which is principally cultivated in the centre of Spain declared vulnerable zone to nitrate pollution by applying the Directive 91/676/CEE. During successive years, a melon crop (Cucumis melo L.) was grown under field conditions. Different doses of ammonium nitrate were used as well as compost derived from the wine-distillery industry which is relevant in this area. Acknowledgements: This project has been supported by INIA-RTA04-111-C3 and INIA-RTA2010-00110-C03. Keywords: Water footprint, nitrogen, fertirrigation, inorganic fertilizers, organic amendments, semiarid conditions. [1] Hoekstra, A.Y. 2003. Virtual water trade. Proceedings of the International Expert Meeting on Virtual Water Trade, Delft, The Netherlands, 12-13 December 2002. Value of Water Research Report Series No. 12, UNESCO-IHE, Delft, The Netherlands.
Simulating the effects of climate and agricultural management practices on global crop yield
NASA Astrophysics Data System (ADS)
Deryng, D.; Sacks, W. J.; Barford, C. C.; Ramankutty, N.
2011-06-01
Climate change is expected to significantly impact global food production, and it is important to understand the potential geographic distribution of yield losses and the means to alleviate them. This study presents a new global crop model, PEGASUS 1.0 (Predicting Ecosystem Goods And Services Using Scenarios) that integrates, in addition to climate, the effect of planting dates and cultivar choices, irrigation, and fertilizer application on crop yield for maize, soybean, and spring wheat. PEGASUS combines carbon dynamics for crops with a surface energy and soil water balance model. It also benefits from the recent development of a suite of global data sets and analyses that serve as model inputs or as calibration data. These include data on crop planting and harvesting dates, crop-specific irrigated areas, a global analysis of yield gaps, and harvested area and yield of major crops. Model results for present-day climate and farm management compare reasonably well with global data. Simulated planting and harvesting dates are within the range of crop calendar observations in more than 75% of the total crop-harvested areas. Correlation of simulated and observed crop yields indicates a weighted coefficient of determination, with the weighting based on crop-harvested area, of 0.81 for maize, 0.66 for soybean, and 0.45 for spring wheat. We found that changes in temperature and precipitation as predicted by global climate models for the 2050s lead to a global yield reduction if planting and harvesting dates remain unchanged. However, adapting planting dates and cultivar choices increases yield in temperate regions and avoids 7-18% of global losses.
Sainju, Upendra M; Stevens, William B; Caesar-Tonthat, Thecan; Liebig, Mark A
2012-01-01
Management practices, such as irrigation, tillage, cropping system, and N fertilization, may influence soil greenhouse gas (GHG) emissions. We quantified the effects of irrigation, tillage, crop rotation, and N fertilization on soil CO, NO, and CH emissions from March to November, 2008 to 2011 in a Lihen sandy loam in western North Dakota. Treatments were two irrigation practices (irrigated and nonirrigated) and five cropping systems (conventional-tilled malt barley [ L.] with N fertilizer [CT-N], conventional-tilled malt barley with no N fertilizer [CT-C], no-tilled malt barley-pea [ L.] with N fertilizer [NT-PN], no-tilled malt barley with N fertilizer [NT-N], and no-tilled malt barley with no N fertilizer [NT-C]). The GHG fluxes varied with date of sampling and peaked immediately after precipitation, irrigation, and/or N fertilization events during increased soil temperature. Both CO and NO fluxes were greater in CT-N under the irrigated condition, but CH uptake was greater in NT-PN under the nonirrigated condition than in other treatments. Although tillage and N fertilization increased CO and NO fluxes by 8 to 30%, N fertilization and monocropping reduced CH uptake by 39 to 40%. The NT-PN, regardless of irrigation, might mitigate GHG emissions by reducing CO and NO emissions and increasing CH uptake relative to other treatments. To account for global warming potential for such a practice, information on productions associated with CO emissions along with NO and CH fluxes is needed. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Madugundu, Rangaswamy; Al-Gaadi, Khalid A; Tola, ElKamil; Hassaballa, Abdalhaleem A; Kayad, Ahmed G
2018-01-01
The crop Water Footprint (WF) can provide a comprehensive knowledge of the use of water through the demarcation of the amount of the water consumed by different crops. The WF has three components: green (WFg), blue (WFb) and grey (WFgr) water footprints. The WFg refers to the rainwater stored in the root zone soil layer and is mainly utilized for agricultural, horticultural and forestry production. The WFb, however, is the consumptive use of water from surface or groundwater resources and mainly deals with irrigated agriculture, industry, domestic water use, etc. While the WFgr is the amount of fresh water required to assimilate pollutants resulting from the use of fertilizers/agrochemicals. This study was conducted on six agricultural fields in the Eastern region of Saudi Arabia, during the period from December 2015 to December 2016, to investigate the spatiotemporal variation of the WF of silage maize and carrot crops. The WF of each crop was estimated in two ways, namely agro-meteorological (WFAgro) and remote sensing (WFRS) methods. The blue, green and grey components of WFAgro were computed with the use of weather station/Eddy covariance measurements and field recorded crop yield datasets. The WFRS estimated by applying surface energy balance principles on Landsat-8 imageries. However, due to non-availability of Landsat-8 data on the event of rainy days, this study was limited to blue component (WFRS-b). The WFAgro of silage maize was found to range from 3545 m3 t-1 to 4960 m3 t-1; on an average, the WFAgro-g, WFAgro-b, and WFAgro-gr are composed of < 1%, 77%, and 22%, respectively. In the case of carrot, the WFAgro ranged between 297 m3 t-1 and 502 m3 t-1. The WFAgro-g of carrot crop was estimated at <1%, while WFAgro-b and WFAgro-gr was 67% and 32%, respectively. The WFAgro-b is occupied as a major portion in WF of silage maize (77%) and carrot (68%) crops. This is due to the high crop water demand combined with a very erratic rainfall, the irrigation is totally provided using groundwater delivered by center pivot irrigation systems. On the other hand, the WFRS-b estimated using Landsat-8 data was varied from 276 (±73) m3 t-1 (carrot) and 2885 (±441) m3 t-1 (silage maize). The variation (RMSE) between WFRS-b and WFAgro-b was about 17% and 14% for silage maize and carrot crops, respectively.
Modelling regional variability of irrigation requirements due to climate change in Northern Germany.
Riediger, Jan; Breckling, Broder; Svoboda, Nikolai; Schröder, Winfried
2016-01-15
The question whether global climate change invalidates the efficiency of established land use practice cannot be answered without systemic considerations on a region specific basis. In this context plant water availability and irrigation requirements, respectively, were investigated in Northern Germany. The regions under investigation--Diepholz, Uelzen, Fläming and Oder-Spree--represent a climatic gradient with increasing continentality from West to East. Besides regional climatic variation and climate change, soil conditions and crop management differ on the regional scale. In the model regions, temporal seasonal droughts influence crop success already today, but on different levels of intensity depending mainly on climate conditions. By linking soil water holding capacities, crop management data and calculations of evapotranspiration and precipitation from the climate change scenario RCP 8.5 irrigation requirements for maintaining crop productivity were estimated for the years 1991 to 2070. Results suggest that water requirement for crop irrigation is likely to increase with considerable regional variation. For some of the regions, irrigation requirements might increase to such an extent that the established regional agricultural practice might be hard to retain. Where water availability is limited, agricultural practice, like management and cultivated crop spectrum, has to be changed to deal with the new challenges. Copyright © 2015 Elsevier B.V. All rights reserved.
Kukal, Meetpal S; Irmak, Suat
2018-02-22
Climate variability and trends affect global crop yields and are characterized as highly dependent on location, crop type, and irrigation. U.S. Great Plains, due to its significance in national food production, evident climate variability, and extensive irrigation is an ideal region of investigation for climate impacts on food production. This paper evaluates climate impacts on maize, sorghum, and soybean yields and effect of irrigation for individual counties in this region by employing extensive crop yield and climate datasets from 1968-2013. Variability in crop yields was a quarter of the regional average yields, with a quarter of this variability explained by climate variability, and temperature and precipitation explained these in singularity or combination at different locations. Observed temperature trend was beneficial for maize yields, but detrimental for sorghum and soybean yields, whereas observed precipitation trend was beneficial for all three crops. Irrigated yields demonstrated increased robustness and an effective mitigation strategy against climate impacts than their non-irrigated counterparts by a considerable fraction. The information, data, and maps provided can serve as an assessment guide for planners, managers, and policy- and decision makers to prioritize agricultural resilience efforts and resource allocation or re-allocation in the regions that exhibit risk from climate variability.
Regional Climate Implications of Large-scale Cultivation of Biofuel Crops
NASA Astrophysics Data System (ADS)
Rowe, C. M.; Oglesby, R. J.; Hays, C. J.; van Etten, A. R.
2008-12-01
Conversion from corn-based ethanol to cellulosic ethanol has the potential to dramatically alter the production of biofuels in the United States and could result in large-scale changes in the agricultural landscape of vast areas of the country. Regions currently dominated by corn production could see widespread planting of switchgrass and other fast-growing, water-efficient sources of cellulose biomass. An often overlooked side effect of these land-cover changes could be a significant alteration of the energy fluxes between the land surface and the atmosphere with profound local, regional, and continental impacts on the climate system. Changes in the surface energy balance result primarily from differences in the seasonality of transpiration from corn versus switchgrass and could be enhanced as a result of a reduced need for irrigation of switchgrass in areas where corn can be produced only under irrigation. Preliminary modeling results using a simple "bucket" land surface model coupled to the WRF mesoscale model have demonstrated increases in summertime average daily maximum temperature of up to 4° C, smaller increases of up to 2° C in nighttime minimum temperatures and reductions in precipitation by up to 25% when corn was changed to switchgrass over the central United States. Improved parameterization of biofuel crops in more sophisticated land surface models will allow us to refine these preliminary estimates and assess the impacts of large-scale conversion to cellulosic biofuel crops, relative to greenhouse gas induced regional climate change.
NASA Astrophysics Data System (ADS)
Ermolaeva, Olga; Zeyliger, Anatoly
2017-04-01
Today world's water systems face formidable threats due to climate change and increasing water withdraw for agriculture, industry and domestic use. Projected in many parts of the earth increases in temperature, evaporation, and drought frequency shrunk water availability and magnify water scarcity. Declining irrigation water supplies threaten the sustainability of irrigated agricultural production which plays a critical role in meeting global food needs. In irrigated agriculture there is a strong call for deep efforts in order on the one hand to improve water efficiency use and on the other to maximize yields. The aim of this research is to provide tool to optimize water application with crop irrigation by sprinkling in order to sustain irrigated agriculture under limited water supply by increasing net returns per unit of water. For this aim some field experimental results of 2012 year growing season of alfalfa, corn and soya irrigated by sprinkling machines crops at left bank of Volga River at Saratov Region of Russia. Additionally a combination of data sets was used which includes MODIS images, local meteorological station and results of SWAP (Soil-Water-Atmosphere-Plant) modeling. This combination was used to estimate crop water stress defined as ratio between actual (ETa) and potential (ETc) evapotranspiration. By this way it was determined the effect of applied irrigation scheduling and water application depths on evapotranspiration, crop productivity and water stress coefficient. Aggregation of actual values of crop water stress and biomass data predicted by SWAP agrohydrological model with weather forecasting and irrigation scheduling was used to indicate of both rational timing and amount of irrigation water allocation. This type of analysis facilitating an efficient water management can be extended to irrigated areas by developing maps of water efficiency application serving as an irrigation advice system for farmers at his fields and as a decision support tool for the authorities on the large perimeter irrigation management. The authors would like to express their gratitude to the Russian Foundation of Basic Research for providing financial support of the project 16-05-01097
Developing wind and/or solar powered crop irrigation systems for the Great Plains
USDA-ARS?s Scientific Manuscript database
Some small scale, off-grid irrigation systems (less than 2.5 ha) that are powered by wind or solar energy are cost effective, but this paper discusses ways to achieve an economical renewable energy powered center pivot irrigation system for crops in the Great Plains. It was found that partitioning t...
Root Zone Sensors for Irrigation Management in Intensive Agriculture
Pardossi, Alberto; Incrocci, Luca; Incrocci, Giorgio; Malorgio, Fernando; Battista, Piero; Bacci, Laura; Rapi, Bernardo; Marzialetti, Paolo; Hemming, Jochen; Balendonck, Jos
2009-01-01
Crop irrigation uses more than 70% of the world’s water, and thus, improving irrigation efficiency is decisive to sustain the food demand from a fast-growing world population. This objective may be accomplished by cultivating more water-efficient crop species and/or through the application of efficient irrigation systems, which includes the implementation of a suitable method for precise scheduling. At the farm level, irrigation is generally scheduled based on the grower’s experience or on the determination of soil water balance (weather-based method). An alternative approach entails the measurement of soil water status. Expensive and sophisticated root zone sensors (RZS), such as neutron probes, are available for the use of soil and plant scientists, while cheap and practical devices are needed for irrigation management in commercial crops. The paper illustrates the main features of RZS’ (for both soil moisture and salinity) marketed for the irrigation industry and discusses how such sensors may be integrated in a wireless network for computer-controlled irrigation and used for innovative irrigation strategies, such as deficit or dual-water irrigation. The paper also consider the main results of recent or current research works conducted by the authors in Tuscany (Italy) on the irrigation management of container-grown ornamental plants, which is an important agricultural sector in Italy. PMID:22574047
Fallow land effects on land-atmosphere interactions in California drought
NASA Astrophysics Data System (ADS)
Lu, Y.; Melton, F. S.; Kueppers, L. M.
2015-12-01
The recent drought in California increased the area of fallow land, which is cropland not planted or irrigated per normal agricultural practice. The effects of fallow land on land-atmosphere interactions in drought years are not well studied, but theoretically should alter local energy balance and surface climate relative to normal years, which in turn could affect neighboring cropland. We examined these effects using a regional climate model (Weather Research and Forecasting model) coupled with a dynamic crop growth model (Community Land Model) that has an irrigation scheme to study the effects of fallow land in 2014, an extreme drought year in California. In our study, we used satellite-derived maps of cultivated and fallowed acreage, and defined summer fallow land in 2014 as the reduced percentage of cultivated land for each grid cell relative to the 2011 cultivated area (2011 was the most recent year following a winter with average or above average precipitation). Using a sensitivity experiment that kept large-scale climate boundary conditions constant, we found that fallow land resulted in even dryer and warmer weather that worsened the drought impact. Fallow land increased 2-meter air temperature by 0.1- 4 °C with 0-80% fallow land, mainly due to an increase in nighttime temperature. Fallow land warmed the atmosphere up to 850hpa during the day, and after sunset, the warmed atmosphere emitted downward longwave radiation that prevented the surface from rapidly cooling, and therefore resulted in warmer nights. Fallow land reduced near surface relative humidity by 5-30% and increased vapor pressure deficit by 0.5-2 kPa. These drier conditions increased the irrigation water demand in the nearby cropland: crops required 1-25% more irrigation with 10-80% fallow land within the same 10km grid cell. Our study suggests that fallow land has large impacts on land-atmosphere interactions and increases irrigation requirements in nearby cropland.
USDA-ARS?s Scientific Manuscript database
Soil and irrigation management have been used to optimize crop production. However,their effects on microclimate, development, and controls of potato diseases have not been adequately quantified. The effects of soil, crop, and water management on development of potato early blight and late blight we...
USDA-ARS?s Scientific Manuscript database
Evapotranspiration estimates for scheduling irrigation must be field specific and real time. Weather station networks provide daily reference ET values, but users need to select crop coefficients for their particular crop and field. A prototype system has been developed that combines satellite image...
NASA Astrophysics Data System (ADS)
Xu, T.; Deines, J. M.; Kendall, A. D.; Hyndman, D. W.
2017-12-01
Irrigation, which has become more common in humid regions, is the largest consumptive water use across the US and the globe. In southwestern Michigan, there has been a dramatic expansion in irrigation water use for row crops (primarily corn and soybean) in the past decade, mostly from groundwater pumping. The rapid expansion of irrigated row crops has potentially profound implications for terrestrial water balances, food production, and local to regional climate. Detailed maps of spatio-temporal changes in irrigation are essential to better understand irrigation impacts. However, accurate monitoring of irrigation area can be difficult in humid regions using remotely sensed methods due to the similarity in greenness between non-irrigated and irrigated areas in most years. Here, we use remote sensing to create annual, 30m-resolution maps of irrigated cropland by integrating Landsat and MODIS satellite products along with the PRISM climate dataset. From these data we developed spatial time series of vegetation and extreme weather indices, including novel indices we developed specifically to maximize detection of irrigation. Using these input data, machine learning classification was then performed over the region to identify irrigated crop area for each year. The resulting annual irrigation maps suggest that total irrigated area in southwestern Michigan increased by 160% from 2000 to 2017. The accuracy of the maps is assessed relative to maps created for an arid region using the same method. The maps can be integrated into hydrologic models to quantify irrigation impacts and support water resources management.
NASA Astrophysics Data System (ADS)
Hernández J., P.; Befani M., R.; Boschetti N., G.; Quintero C., E.; Díaz E., L.; Lado, M.; Paz-González, A.
2015-04-01
The Avellaneda District, located in northeastern of Santa Fe Province, Argentina, has an average annual rainfall of 1250 mm per year, but with a high variability in their seasonal distribution. Generally, the occurrence of precipitation in winter is low, while summer droughts are frequent. The yearly hydrological cycle shows a water deficit, given that the annual potential evapotranspiration is estimated at 1330 mm. Field crops such as soybean, corn, sunflower and cotton, which are affected by water stress during their critical growth periods, are dominant in this area. Therefore, a supplemental irrigation project has been developed in order to identify workable solutions. This project pumps water from Paraná River to provide a water supply to the target area under irrigation. A pressurized irrigation system operating on demand provides water to a network of channels, which in turn deliver water to farms. The scheduled surface of irrigation is 8800 hectares. The maximum flow rate was designed to be 8.25 m3/second. The soils have been classified as Aquic Argiudolls in areas of very gentle slopes, and Vertic Argiudolls in flat and concave reliefs; neither salinity nor excess sodium affect the soils of the study are. The objective of this study was to provide a quantitative data set to manage the irrigation project, through the determination of available water (AW), easily available water (EAw) and optimal water range (or interval) of the soil horizons. The study has been conducted in a text area of 1500 hectares in surface. Five soil profiles were sampled to determine physical properties (structure stability, effective root depth, infiltration, bulk density, penetration resistance and water holding capacity), chemical properties (pH, cation exchange capacity, base saturation, salinity, and sodium content ) and morphological characteristics of the successive horizons. Also several environmental characteristics were evaluated, including: climate, topographic conditions, relief, general and slope position, erosion, natural vegetation and agricultural crops. Indeed the computed available water (AW) content and easily available water (EAw) content values depended on bulk density, field capacity and permanent wilting point, but also they were affected by the soil penetration resistance measured to a depth of 80 cm; this parameter limits the extent of the soil volume explored by plant roots and therefore EAw content. Moreover, soil penetration resistance enables to take into account the concept of optimal water interval, which indicates how soil compaction limits the levels of easily available water that really can be extracted by the crop. The estimated values of EAw water ranged from 74 to 133 mm for the profiles studies. When including the concept of mechanical resistance to penetration to obtain the value of the optimal water interval, the above values decreased, ranging between 34 and 57 mm; this was mainly explained on the basis of the true depth of exploration by plant roots of the soil profiles. Based on the recorded values of the soil mechanical resistance to penetration, it was concluded that sunflower and corn crops will be mostly affected on their growth and root development. Subsequently, and for a maximum consumptive use of 10 mm/day, the commonly used irrigation interval of 13 days, should decrease to 6 days, if the new methodology is used i.e. if the limitations of soil depth exploration by crop roots are taken into account. This result is consistent with those from current practices under non irrigated conditions, where it has been shown that crop yields are affected by water shortage provided that an important precipitation doesn't occur among such interval.
NASA Astrophysics Data System (ADS)
Thebo, A.
2016-12-01
Urban wastewater provides a reliable, nutrient rich source of irrigation water for downstream agricultural producers. However, globally, less than ten percent of collected wastewater receives any form of treatment, resulting in the widespread indirect reuse of untreated, diluted wastewater from surface water sources. This research explores these links between water scarcity, anthropogenic drivers of water quality, and adaptation strategies farmer's employ through a case study in Dharwad, a mid-sized South Indian city. This study took an interdisciplinary approach, incorporating survey based research with geospatial analysis, and molecular methods (for waterborne pathogen detection) to develop a systems level understanding of the drivers, health risks, and adaptation strategies associated with the indirect reuse of wastewater in irrigated agriculture. In Dharwad, farmers with better access to wastewater reported growing more water-intensive, but higher value vegetable crops. While farmers further downstream tended to grow more staple crops. This study evaluated levels of culturable E. coli and diarrheagenic E. coli pathotype gene targets to assess contamination in irrigation water, soil, and on produce from farms. Irrigation water source was a major factor affecting the concentrations of culturable E. coli detected in soil samples and on greens. However, even when irrigation water was not contaminated (all borewell water samples) some culturable E. coli were present at low concentrations in soil and on produce samples, suggesting additional sources of contamination on farms. Maximum temperatures within the previous week showed a significant positive association with concentrations of E. coli on wastewater irrigated produce. This presentation will focus on discussing the ways in which urban wastewater management, climate, irrigation practices and cultivation patterns all come together to define the risks and benefits posed via the indirect reuse of wastewater.
NASA Astrophysics Data System (ADS)
Li, Mo; Fu, Qiang; Singh, Vijay P.; Ma, Mingwei; Liu, Xiao
2017-12-01
Water scarcity causes conflicts among natural resources, society and economy and reinforces the need for optimal allocation of irrigation water resources in a sustainable way. Uncertainties caused by natural conditions and human activities make optimal allocation more complex. An intuitionistic fuzzy multi-objective non-linear programming (IFMONLP) model for irrigation water allocation under the combination of dry and wet conditions is developed to help decision makers mitigate water scarcity. The model is capable of quantitatively solving multiple problems including crop yield increase, blue water saving, and water supply cost reduction to obtain a balanced water allocation scheme using a multi-objective non-linear programming technique. Moreover, it can deal with uncertainty as well as hesitation based on the introduction of intuitionistic fuzzy numbers. Consideration of the combination of dry and wet conditions for water availability and precipitation makes it possible to gain insights into the various irrigation water allocations, and joint probabilities based on copula functions provide decision makers an average standard for irrigation. A case study on optimally allocating both surface water and groundwater to different growth periods of rice in different subareas in Heping irrigation area, Qing'an County, northeast China shows the potential and applicability of the developed model. Results show that the crop yield increase target especially in tillering and elongation stages is a prevailing concern when more water is available, and trading schemes can mitigate water supply cost and save water with an increased grain output. Results also reveal that the water allocation schemes are sensitive to the variation of water availability and precipitation with uncertain characteristics. The IFMONLP model is applicable for most irrigation areas with limited water supplies to determine irrigation water strategies under a fuzzy environment.
NASA Astrophysics Data System (ADS)
Wei, X.; Bailey, R. T.
2017-12-01
Agricultural irrigated watersheds in semi-arid regions face challenges such as waterlogging, high soil salinity, reduced crop yield, and leaching of chemical species due to extreme shallow water tables resulting from long-term intensive irrigation. Hydrologic models can be used to evaluate the impact of land management practices on water yields and groundwater-surface water interactions in such regions. In this study, the newly developed SWAT-MODFLOW, a coupled surface/subsurface hydrologic model, is applied to a 950 km2 watershed in the Lower Arkansas River Valley (southeastern Colorado). The model accounts for the influence of canal diversions, irrigation applications, groundwater pumping, and earth canal seepage losses. The model provides a detailed description of surface and subsurface flow processes, thereby enabling detailed description of watershed processes such as runoff, infiltration, in-streamflow, three-dimensional groundwater flow in a heterogeneous aquifer system with sources and sinks (e.g. pumping, seepage to subsurface drains), and spatially-variable surface and groundwater exchange. The model was calibrated and tested against stream discharge from 5 stream gauges in the Arkansas River and its tributaries, groundwater levels from 70 observation wells, and evapotranspiration (ET) data estimated from satellite (ReSET) data during the 1999 to 2007 period. Since the water-use patterns within the study area are typical of many other irrigated river valleys in the United States and elsewhere, this modeling approach is transferable to other regions.
Study of the hydrological functionning of the irrigated crops in the southern mediterranean basin
NASA Astrophysics Data System (ADS)
Khabba, Said; Jarlan, Lionel; Er-Raki, Salah; Le Page, Michel; Merlin, Olivier; Ezzahar, Jamal; Kharrou, Mohamed H.
2015-04-01
In southern Mediterranean region water consumption has significantly increased over the last decades, while available water resources are becoming increasingly scarce. In Morocco, irrigation is highly water demanding: it is estimated that 83% of available resources is dedicated to agriculture with efficiency lower than 50% (Plan Bleu, 2009). In the semiarid region of Tensift Al-Haouz (center of Morocco), typical of southern Mediterranean basin, crop irrigation is inevitable for growth and development. In this situation, and to preserve water resources, the rational management of water irrigation is necessary. This objective is one of the priorities of the research program SudMed (Chehbouni et al., 2008) and the Joint Mixed Laboratory TREMA (Khabba et al. 2013), installed in Marrakech since 2002 and 2011, respectively. In these two programs, the scientific approach adopted, to monitor water transfers in soil-plant-atmosphere system, is based on the synergistic use of the mathematical modeling, the satellite observations and in situ data. Thus, during the decade 2002-2012, 17 experiments on dominant crops in the region (wheat, olive, orange, sugar beet, apricot) were performed. In these experiments, the different terms of water and heat balances exchanged between land surface and atmosphere are controlled with different devices. Results showed that the water losses by evaporation can reach 28% of water inputs for the flooding irrigation site and are obviously lower (about 18-20 % on average) for the drip irrigation sites. Concerning the deep percolation, results are surprising: water losses for the drip irrigation are in the range 29-41% of water input, whereas theses losses are between 26 and 31% for flooding irrigation. Concerning the modeling component, several models ranging from the most simple (FAO-56) to the most complex (i.e. SVAT: Soil Vegetation Atmosphere Transfer) were implemented to estimate the spatio-temporal variability of ET. The results showed that the physically based SVATs such as ISBA provide good estimates of surface fluxes over all sites once a proper calibration is carried out. However, they required several input parameters that are not routinely available at the appropriate spatial scale. For operational purposes, simpler approaches such as the FAO-56 and the TSEB models showed a good estimate of ET at field scale. Also, the FAO-56 approach was adapted to use a satellite-based vegetation index. It was calibrated and validated on the Haouz plain, for the main crops (wheat, olive and citrus). Its implementation was validated using a Landsat TM image time series and also using low resolution images. The results showed that despite the simplicity of the model, spatial estimates of ET were reasonable. This model was converted in software for Satellite Monitoring of Irrigation. However, the FAO-56 method combined with solar remote sensing data alone was not sufficient to accurately estimate water consumption, especially when soil evaporation and stress under full vegetation cover conditions occurred. In this regard, we directly assimilated snapshot evaporation data that could be obtained through the resolution of a simple energy budget forced by TIR observations. These preliminary results showed a clear improvement of the seasonal ET estimates.
Global assessment of urban and peri-urban agriculture: irrigated and rainfed croplands
NASA Astrophysics Data System (ADS)
Thebo, A. L.; Drechsel, P.; Lambin, E. F.
2014-11-01
The role of urban agriculture in global food security is a topic of increasing discussion. Existing research on urban and peri-urban agriculture consists largely of case studies that frequently use disparate definitions of urban and peri-urban agriculture depending on the local context and study objectives. This lack of consistency makes quantification of the extent of this practice at the global scale difficult. This study instead integrates global data on croplands and urban extents using spatial overlay analysis to estimate the global area of urban and peri-urban irrigated and rainfed croplands. The global area of urban irrigated croplands was estimated at about 24 Mha (11.0 percent of all irrigated croplands) with a cropping intensity of 1.48. The global area of urban rainfed croplands found was approximately 44 Mha (4.7 percent of all rainfed croplands) with a cropping intensity of 1.03. These values were derived from the MIRCA2000 Maximum Monthly Cropped Area Grids for irrigated and rainfed crops and therefore their sum does not necessarily represent the total urban cropland area when the maximum extent of irrigated and rainfed croplands occurs in different months. Further analysis of croplands within 20 km of urban extents show that 60 and 35 percent of, respectively, all irrigated and rainfed croplands fall within this distance range.
NASA Astrophysics Data System (ADS)
Raju Pokkuluri, Venkat; Rao, Diwakar Parsi Guru; Hazra, Sugata; Srikant Kulkarni, Sunil
2017-04-01
India uses its 85 percent of available water resources for irrigation making it the country with largest net irrigated area in the world. With one of the largest delta plains, sustaining the needs of irrigation supplies is critical for food security and coping with challenges of climate change. The extensive development of upstream river basins/catchments is posing serious challenge and constrains to the water availability to delta regions, which depend on the controlled/regulated flows from the upstream catchments. The irrigation water demands vary due to changes in agricultural practices, cropping pattern and changing climate conditions. Estimation of realistic irrigation water demand and its trend over time is critical for meeting the supplementary water needs of productive agricultural lands in delta plains and there by coping the challenges of extensive upstream river basin development and climate change. The present study carried out in delta districts of Mahanadi river in Odisha State of India, wherein the long-term trends in field level irrigation water requirements were estimated, both on spatial & temporal scales, using hydrological modeling framework. This study attempts to estimate field level irrigation water requirements through simulation of soil water balance during the crop growing season through process based hydrological modeling framework. The soil water balance computations were carried out using FAO-56 framework, by modifying the crop coefficient (Kc) proportional to the water stress coefficient (Ks), which is a function of root zone depletion of water. Daily meteorological data, spatial cropping pattern, terrain are incorporated in the soil water balance simulation in the model. The irrigation water demand is derived considering the exclusion of soil water stress for each model time step. The field level irrigation water requirement at 8 day interval had been estimated for the each Rabi season (post-monsoon) spanning over 1986 to 2015. The results indicate that irrigation water requirements show spatial and temporal changes and tend to deviate from notional/envisaged demands. Validation of estimated irrigation demand is attempted through correlation of gap in supply and demand with the trends in crop water stress and crop production during the study years. Crop water Stress Index (CWSI), which is the ratio of deficit of actual evapotranspiration (AET) from the potential evapotranspiration (PET) and is derived from MODIS Evapotranspiration data. Agricultural production data is used from State/Central government statistics. The attempted methodology provides opportunities to estimate future irrigation water demand under projected climate change scenarios and for planning for basin level water resources development sustaining the delta agriculture, which are projected to be more vulnerable to climate change.
The Response and Repairing of Three Kinds of Crops on Xi’an’s Sewage Irrigation Area Soil
NASA Astrophysics Data System (ADS)
Xin, H.; Zhimei, Z.; Lei, H.; Huan, L.; Tian, Z.
2017-10-01
This paper focuses on the XiChaZhai village’s vegetable soil which is located in the northern suburbs of Xi’an and on its vegetables, thus analyzes the quality of sewage irrigation region soil and its influence on vegetables through the measurement of Cu, Zn, Pb, Cd’s content in samples. The results show that the research area soil contains apparently excessive heavy metals, and there exists significant differences of different elements’ integrated intensity in soil, the content declines in sequence from Cd, Zn, Pb to Cu. The four heavy metals’ contents in sewage irrigation region soil vary greatly from that in non-sewage irrigation region soil(P<0.01). Raphanus sativus and Ottelia acuminate have favorable effects on Cd and Cu’s accumulation. Three crops having repairing effects on Xi’an sewage irrigation region soil are Raphanus sativus, Ottelia acuminate and Brassica chinensis, in that order. Different crop tissues differ in the accumulation of heavy metal, the order according as roots, stem and leaves, fruits. Therefore, based on differences of various crops on heavy metals’ absorption and translocation, appropriate crops should be scientifically planted in heavy metal contaminated area soil.
Impact of Seasonal Variability in Water, Plant and Soil Nutrient Dynamics in Agroecosystems
NASA Astrophysics Data System (ADS)
Pelak, N. F., III; Revelli, R.; Porporato, A. M.
2017-12-01
Agroecosystems cover a significant fraction of the Earth's surface, making their water and nutrient cycles a major component of global cycles across spatial and temporal scales. Most agroecosystems experience seasonality via variations in precipitation, temperature, and radiation, in addition to human activities which also occur seasonally, such as fertilization, irrigation, and harvesting. These seasonal drivers interact with the system in complex ways which are often poorly characterized. Crop models, which are widely used for research, decision support, and prediction of crop yields, are among the best tools available to analyze these systems. Though normally constructed as a set of dynamical equations forced by hydroclimatic variability, they are not often analyzed using dynamical systems theory and methods from stochastic ecohydrology. With the goal of developing this viewpoint and thus elucidating the roles of key feedbacks and forcings on system stability and on optimal fertilization and irrigation strategies, we develop a minimal dynamical system which contains the key components of a crop model, coupled to a carbon and nitrogen cycling model, driven by seasonal fluctuations in water and nutrient availability, temperature, and radiation. External drivers include seasonally varying climatic conditions and random rainfall forcing, irrigation and fertilization as well as harvesting. The model is used to analyze the magnitudes and interactions of the effects of seasonality on carbon and nutrient cycles, crop productivity, nutrient export of agroecosystems, and optimal management strategies with reference to productivity, sustainability and profitability. The impact of likely future climate scenarios on these systems is also discussed.
USDA-ARS?s Scientific Manuscript database
The SMOS (Soil Moisture and Ocean Salinity) mission provides surface soil moisture (SM) maps at a mean resolution of ~50 km. However, agricultural applications (irrigation, crop monitoring) and some hydrological applications (floods and modeling of small basins) require higher resolution SM...
Heavy metals transfer in the olive tree and assessment of food contamination risk.
Zaanouni, Nada; Gharssallaoui, Mariem; Eloussaief, Mabrouk; Gabsi, Slimane
2018-03-11
Due to constraints of fresh water for agricultural irrigation, wastewater was used for irrigation of agricultural land as alternative water resources in arid and semi-arid Tunisian regions. However, long-term irrigation may cause contamination by heavy metals in the soil as well as for crops, thus becoming a threat to humans. To understand the effect of irrigation with wastewater on the concentrations of heavy metals Cr, Cu, Mn, Zn, and Pb, in soil and plants, soil samples and plants were collected and analyzed. Results have shown that all soil samples do not exhibit extreme values. The content of heavy metals in the surface layer (0-30 cm) is much higher than that in depth. Overall, the concentrations of Mn, Pb, Cu, Cr, and Zn in soil were found to be lower than the authorized national safety limits. Moreover, the content in both parts of forage crops have not exceeded the WHO standard. For olive trees, no negative values were found in the different organs, which was also true for the extracted oil. An exception happened for the oils produced from fallen olives in direct contact with the wastewater and the soil. Therefore, to ensure food security and wastewater use for irrigation, monitoring and control of pollution is required. Graphical abstract Biomass production from treated wastewater without risk.
EnviroAtlas - Agricultural Water Demand by 12-Digit HUC for the Conterminous United States
The national agricultural water demand metric provides insight into the amount of water currently used for agricultural irrigation in the contiguous United States. The values are based on 2005 irrigation water use; combined 2010 crop, 2006 land use, and 2001 remotely sensed irrigation location estimates; and have been summarized by watershed or 12-digit hydrologic unit code (HUC). Agricultural irrigation water use, as defined in this case, meets a variety of needs before, during, and after growing seasons (e.g., dust suppression, field preparation, chemical application, weed control, salt removal from root zones, frost protection, crop cooling, and harvesting). Estimates include self-supplied surface and groundwater, as well as supplies from irrigation-specific organizations (e.g., companies, districts, cooperatives, government). This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).
NASA Astrophysics Data System (ADS)
Lorite, I. J.; Mateos, L.; Fereres, E.
2005-01-01
SummaryThe simulations of dynamic, spatially distributed non-linear models are impacted by the degree of spatial and temporal aggregation of their input parameters and variables. This paper deals with the impact of these aggregations on the assessment of irrigation scheme performance by simulating water use and crop yield. The analysis was carried out on a 7000 ha irrigation scheme located in Southern Spain. Four irrigation seasons differing in rainfall patterns were simulated (from 1996/1997 to 1999/2000) with the actual soil parameters and with hypothetical soil parameters representing wider ranges of soil variability. Three spatial aggregation levels were considered: (I) individual parcels (about 800), (II) command areas (83) and (III) the whole irrigation scheme. Equally, five temporal aggregation levels were defined: daily, weekly, monthly, quarterly and annually. The results showed little impact of spatial aggregation in the predictions of irrigation requirements and of crop yield for the scheme. The impact of aggregation was greater in rainy years, for deep-rooted crops (sunflower) and in scenarios with heterogeneous soils. The highest impact on irrigation requirement estimations was in the scenario of most heterogeneous soil and in 1999/2000, a year with frequent rainfall during the irrigation season: difference of 7% between aggregation levels I and III was found. Equally, it was found that temporal aggregation had only significant impact on irrigation requirements predictions for time steps longer than 4 months. In general, simulated annual irrigation requirements decreased as the time step increased. The impact was greater in rainy years (specially with abundant and concentrated rain events) and in crops which cycles coincide in part with the rainy season (garlic, winter cereals and olive). It is concluded that in this case, average, representative values for the main inputs of the model (crop, soil properties and sowing dates) can generate results within 1% of those obtained by providing spatially specific values for about 800 parcels.
NASA Technical Reports Server (NTRS)
Parada, N. D. J. (Principal Investigator); Deassuncao, G. V.; Moreira, M. A.; Novaes, R. A.
1984-01-01
The development of a methodology for annual estimates of irrigated rice crop in the State of Rio Grande do Sul, Brazil, using remote sensing techniques is proposed. The project involves interpretation, digital analysis, and sampling techniques of LANDSAT imagery. Results are discussed from a preliminary phase for identifying and evaluating irrigated rice crop areas in four counties of the State, for the crop year 1982/1983. This first phase involved just visual interpretation techniques of MSS/LANDSAT images.
NASA Astrophysics Data System (ADS)
Amparo Martinez-Gimeno, Maria; Provenzano, Giuseppe; Bonet, Luis; Intrigliolo, Diego S.; Badal, Eduardo; Ballestrer, Carlos
2017-04-01
In Mediterranean countries, water scarcity represents a real environmental concern at present and, according to the current climate change models predictions, the problem will be amplified in the future. In order to deal with this issue, application of strategies aimed to optimize the water resources in agriculture and to increase water use efficiency have become essential. On the one hand, it is important the election of the appropriate irrigation system for each particular case. On the other hand, identify the best management options for that specific irrigation system is crucial to optimize the available water resources without affecting yield. When using water saving strategies, however, it is a must to monitor the soil and/or crop water status in order to know the level of stress reached by the plants and to avoid levels that could lead to detrimental effects on yield. Stem water potential, ψstem, expressing the instantaneous condition of crop water stress, is considered a robust indicator of crop water status. The main objective of this study was to assess the performance of a surface (DI) and subsurface (SDI) drip irrigation system in a citrus orchard with 7 (DI7, SDI7) or 14 emitters (DI14, SDI14) per plant, in terms of irrigation water use efficiency (IWUE) and possible amount of water saving. The experiment was carried out in 2014 and 2015 in Alberique, Spain, (39˚ 7'31" N, 0˚ 33'17" W), in a commercial orchard (Citrus clementina, Hort. ex Tan. 'Arrufatina') in which four different treatments with three replications (12 sub-plots) were prepared according to a complete randomized block design. Irrigation doses and timing were scheduled based on the estimated maximum crop evapotranspiration corrected according to measurements of ψstem and soil water content, and weather forecasts. In order to limit the maximum crop water stress, the thresholds of ψstem were assumed in the range between -0.8 and -1.0 MPa from January to June and between -1.0 and -1.2 MPa in the remaining period of the year. In each sub-plot, soil water contents at different depths were monitored with a Frequency Domain Reflectometry probe (EnviroScan, Sentek, Stepney, Australia.), whereas ψstem values were acquired approximately weekly, with a Scholander chamber (Model 600 Pressure Chamber Instrument), on leaves wrapped in bags at least one hour before measurements. At the end of each season, the number of fruit per plant, the average fruit weight, the total yield and their corresponding variability were determined for each treatment. The results showed that within both DI and SDI, treatments with the double number of emitters per plant had the highest yield, number of fruit, fruit weight and IWUE, although with no statistically significant differences. IWUE associated to DI and SDI was, on average for the two years, 6.5 and 7.4 kg/m3, respectively. The best management option was achieved with the SDI14, to which corresponded the minimum seasonal irrigation volumes, with water savings compared to DI7 of about 23% and 28% in 2014 and 2015, respectively.
Remote Sensing of Vineyard FPAR, with Implications for Irrigation Scheduling
NASA Technical Reports Server (NTRS)
Johnson, Lee F.; Scholasch, Thibaut
2004-01-01
Normalized difference vegetation index (NDVI) data, acquired at two-meter resolution by an airborne ADAR System 5500, were compared with fraction of photosynthetically active radiation (FPAR) absorbed by commercial vineyards in Napa Valley, California. An empirical line correction was used to transform image digital counts to surface reflectance. "Apparent" NDVI (generated from digital counts) and "corrected" NDVI (from reflectance) were both strongly related to FPAR of range 0.14-0.50 (both r(sup 2) = 0.97, P < 0.01). By suppressing noise, corrected NDVI should form a more spatially and temporally stable relationship with FPAR, reducing the need for repeated field support. Study results suggest the possibility of using optical remote sensing to monitor the transpiration crop coefficient, thus providing an enhanced spatial resolution component to crop water budget calculations and irrigation management.
Quasi 3D modelling of water flow in the sandy soil
NASA Astrophysics Data System (ADS)
Rezaei, Meisam; Seuntjens, Piet; Joris, Ingeborg; Boënne, Wesley; De Pue, Jan; Cornelis, Wim
2016-04-01
Monitoring and modeling tools may improve irrigation strategies in precision agriculture. Spatial interpolation is required for analyzing the effects of soil hydraulic parameters, soil layer thickness and groundwater level on irrigation management using hydrological models at field scale. We used non-invasive soil sensor, a crop growth (LINGRA-N) and a soil hydrological model (Hydrus-1D) to predict soil-water content fluctuations and crop yield in a heterogeneous sandy grassland soil under supplementary irrigation. In the first step, the sensitivity of the soil hydrological model to hydraulic parameters, water stress, crop yield and lower boundary conditions was assessed after integrating models at one soil column. Free drainage and incremental constant head conditions were implemented in a lower boundary sensitivity analysis. In the second step, to predict Ks over the whole field, the spatial distributions of Ks and its relationship between co-located soil ECa measured by a DUALEM-21S sensor were investigated. Measured groundwater levels and soil layer thickness were interpolated using ordinary point kriging (OK) to a 0.5 by 0.5 m in aim of digital elevation maps. In the third step, a quasi 3D modelling approach was conducted using interpolated data as input hydraulic parameter, geometric information and boundary conditions in the integrated model. In addition, three different irrigation scenarios namely current, no irrigation and optimized irrigations were carried out to find out the most efficient irrigation regime. In this approach, detailed field scale maps of soil water stress, water storage and crop yield were produced at each specific time interval to evaluate the best and most efficient distribution of water using standard gun sprinkler irrigation. The results show that the effect of the position of the groundwater level was dominant in soil-water content prediction and associated water stress. A time-dependent sensitivity analysis of the hydraulic parameters showed that changes in soil water content are mainly affected by the soil saturated hydraulic conductivity Ks in a two-layered soil. Results demonstrated the large spatial variability of Ks (CV = 86.21%). A significant negative correlation was found between ln Ks and ECa (r = 0.83; P≤0.01). This site-specific relation between ln Ks and ECa was used to predict Ks for the whole field after validation using an independent dataset of measured Ks. Result showed that this approach can accurately determine the field scale irrigation requirements, taking into account variations in boundary conditions and spatial variations of model parameters across the field. We found that uniform distribution of water using standard gun sprinkler irrigation is not an efficient approach since at locations with shallow groundwater, the amount of water applied will be excessive as compared to the crop requirements, while in locations with a deeper groundwater table, the crop irrigation requirements will not be met during crop water stress. Numerical results showed that optimal irrigation scheduling using the aforementioned water stress calculations can save up to ~25% irrigation water as compared to the current irrigation regime. This resulted in a yield increase of ~7%, simulated by the crop growth model.
Optimal crop selection and water allocation under limited water supply in irrigation
NASA Astrophysics Data System (ADS)
Stange, Peter; Grießbach, Ulrike; Schütze, Niels
2015-04-01
Due to climate change, extreme weather conditions such as droughts may have an increasing impact on irrigated agriculture. To cope with limited water resources in irrigation systems, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand at the same time. For modeling the regional water demand, local (and site-specific) water demand functions are used which are derived from optimized agronomic response on farms scale. To account for climate variability the agronomic response is represented by stochastic crop water production functions (SCWPF). These functions take into account different soil types, crops and stochastically generated climate scenarios. The SCWPF's are used to compute the water demand considering different conditions, e.g., variable and fixed costs. This generic approach enables the consideration of both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance IRrigation) project a prototype of a decision support system is developed which helps to evaluate combined water supply and demand management policies.
Estimated water use and general hydrologic conditions for Oregon, 1985 and 1990
Broad, T.M.; Collins, C.A.
1996-01-01
Water-use information is vital to planners, engineers, and hydrologists in water resources. This report is a compilation of water-use information for Oregon for calendar years 1985 and 1990. The report presents water-use data by geographic region for several categories of use, including public supply, domestic, commercial, industrial, mining, thermoelectric power, hydroelectric power, live-stock, irrigation, reservoir evaporation, and wastewater treatment. Hydroelectric power is the only instream use discussed; all other uses are considered offstream. The Appendix presents 1985 and 1990 data by region and by drainage basin for the previously mentioned categories of use. The Cascade Range divides Oregon into two distinct climatic zones. The area west of the Cascade Range has an average annual precipitation that ranges from 40 to 200 inches, and precipitation in the area east of the Cascade Range ranges from 10 to 20 inches. The differences in precipitation and geology have an effect on the sources, uses, and amounts of water withdrawn. Most of the large public-supply systems west of the Cascade Range rely on surface water, whereas many of the large public-supply systems east of the Cascade Range use on wells or springs. Irrigators west of the Cascade Range rely primarily on nearby surface- water sources; however, irrigators east of the Cascade Range use primarily surface water that commonly is delivered from distant sources through irrigation ditches. A variety of methods was used to estimate water-use information. Most withdrawals for public-water suppliers were metered; however, irrigation withdrawals usually were estimated by using information on crops, climate, application efficiencies, and conveyance losses. The accuracy of the estimated total withdrawal values for public supply was estimated to be within 4 percent of the values that would be obtained if all public-supply withdrawals were metered. Total withdrawals for irrigation were estimated to be within 40 percent of metered irrigation withdrawals. The estimates-of-error are presented to show the relative, rather than absolute, accuracy of the data for each water-use category. A total of 8,400 million gallons of water per day was withdrawn in Oregon during 1990, about 1,900 million gallons per day more than the 6,500 million gallons per day withdrawn in 1985. Whereas actual water use increased in 1990, the major differences between 1985 and 1990 were attributed to the inclusion of offstream fish hatcheries, the use of different crop coefficients to estimate irrigation, and the availability of more detailed information in the 1990 estimates. Surface-water withdrawals accounted for 92 percent of the total withdrawals in 1990; irrigation was the largest category of water use, accounting for 82 percent of the total withdrawals.
NASA Astrophysics Data System (ADS)
Scanlon, B. R.; Pei, H.; Shen, Y.
2014-12-01
The North China Plain (NCP) and U.S. High Plains play critical roles in food production, which relies heavily on groundwater resources for irrigation and nutrients. Here we evaluate food production in terms of resource availability (water and nutrients) and impacts on resources (groundwater quantity and quality) within the context of climate forcing. Double cropping of corn and wheat in the NCP under intensive irrigation (80 - 90% of cropland) and massive N fertilization (384 kg/ha) resulted in total corn plus wheat yields of 13.4 kg/ha (2002 - 2011). In contrast, single cropping of corn on the USHP under less intensive irrigation (40% of cropland) and N fertilization (90 kg/ha) resulted in only 15% lower yield in the USHP (11.7 kg/ha) than in the NCP. However, irrigation essentially decouples crop production from climate extremes. Average corn and wheat yield in the NCP over the past three decades is not correlated with precipitation. Irrigated corn yield in the north and central USHP was actually higher during the recent 2012 drought by up to ~ 30% relative to the 30 year long-term mean yield whereas rainfed corn yield decreased by ~50% during the drought. The main impact of climate extremes on the aquifers is indirect through increased irrigation pumpage for crop production rather than direct through changes in recharge. Effects of crop production on groundwater quality should be much greater in the NCP because of ~4 times higher fertilizer application relative to that in the USHP. Field research experiments in the NCP indicate that much of this fertilizer application (> 200 kg N/ha) does not impact yield and could potentially leach into underlying aquifers. Projected groundwater depletion in these aquifers should result in a shift from intensive irrigation to more rainfed crop production, increasing vulnerability of crop production to climate extremes.
USDA-ARS?s Scientific Manuscript database
The AquaCrop model of crop growth, water use, yield and water use efficiency (WUE) is intended for use by extension personnel, farm and irrigation managers, planners and other less advanced users of simulation models in irrigation planning and scheduling. It could be useful in estimating changes in ...
USDA-ARS?s Scientific Manuscript database
Improving crop water use (both agronomic and biological) is critical to most cropping areas around the world. The persistance of adverse climate conditions and predicted decreased availability of fresh water for crop production are the largest challenges to agriculture in the coming decades. Our pri...
USDA-ARS?s Scientific Manuscript database
Soil and irrigation management have been used to optimize crop production; however,their effects on microclimate, development, and potato diseases have not been adequately quantified. The effects of soil, crop, and water management on development of potato early blight and late blight were quantifie...
Evapotranspiration-based irrigation scheduling of lettuce and broccoli
USDA-ARS?s Scientific Manuscript database
Estimation of crop evapotranspiration supports efficient irrigation water management, which in turn supports water conservation, mitigation of groundwater depletion/degradation, energy savings, and crop quality maintenance. Past research in California has revealed strong relationships between fract...
Model development for prediction of soil water dynamics in plant production.
Hu, Zhengfeng; Jin, Huixia; Zhang, Kefeng
2015-09-01
Optimizing water use in agriculture and medicinal plants is crucially important worldwide. Soil sensor-controlled irrigation systems are increasingly becoming available. However it is questionable whether irrigation scheduling based on soil measurements in the top soil could make best use of water for deep-rooted crops. In this study a mechanistic model was employed to investigate water extraction by a deep-rooted cabbage crop from the soil profile throughout crop growth. The model accounts all key processes governing water dynamics in the soil-plant-atmosphere system. Results show that the subsoil provides a significant proportion of the seasonal transpiration, about a third of water transpired over the whole growing season. This suggests that soil water in the entire root zone should be taken into consideration in irrigation scheduling, and for sensor-controlled irrigation systems sensors in the subsoil are essential for detecting soil water status for deep-rooted crops.
NASA Astrophysics Data System (ADS)
Oh, D.; Ryu, J. H.; Cho, J.
2017-12-01
Estimation of the crop evapotranspiration (ETc), as a representative of crop water needs, is important for not only high crop productivity, but also improving irrigation water management. In farm lands crop coefficient (Kc), the ratio of ETc to potential ET, is often used to simply estiamte ETc. However, the traits of Kc under the global warming condition will different with current one because plant transpiration and surface evaporaiton will be changed by the alternative crop growth and evaporative energy. In this study, Non-Weighting Lysimeter (NWL) was used to directly estimate ETc under the warmed condition, particularly for paddy riace which has one of lower water use efficiency. The different air t emperature (Ta) conditions for the NWL were provided by Temperature Gradient Chamber (TGC), which was formed gradually warmed conditions. The water body evporation and paddy rice evapotransipiration in the NWL were at the two places of ambient Ta (AT) and AT+3° in the TGC. In addition, we installed Infra-Red thermometer (IRT) to understand the surface energy balance. The result was shown that the different partitioning of evaporation and transpiration of paddy rice at the AT+3°, comparing at AT. Further, the water use efficiency, the ratio of yield to total ET, was also decreased in the warmed condition. These experiments for paddy rice ET in the warmed conditions during growth period will be useful to understand the effect of global warming on the hydrological cycle and manamge the irrigation schedule for more efficient water use.
Loveland, Thomas R.; Johnson, Gary E.
1983-01-01
Landsat data and 1:24 000-scale aerial photographs were initially used to map the expansion of irrigation from 1973 to 1979 and to identify crops under irrigation in 1979. The crop data were then used with historical water requirement figures and digital topographic and hydrographic data to estimate water and power use for the 1979 irrigation season. The final project task involved production of a composite map of land suitability for irrigation development based on land cover (from Landsat), landownership, soil irrigability, slope gradient, and potential energy costs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong
In this paper, the effects of irrigation on global surface water (SW) and groundwater (GW) resources are investigated by performing simulations using Community Land Model 4.0 (CLM4) at 0.5-degree resolution driven by downscaled/bias-corrected historical simulations and future projections from five General Circulation Models (GCMs) for 1950-2099. For each climate scenario, three sets of numerical experiments were configured: (1) a control experiment (CTRL) in which all crops are assumed to be rainfed; (2) an irrigation experiment (IRRIG) in which the irrigation module using only SW for irrigation is activated; and (3) a groundwater pumping experiment (PUMP) in which a groundwater pumpingmore » scheme coupled with the irrigation module is activated for conjunctive use of SW and GW for irrigation. The parameters associated with irrigation and groundwater pumping are calibrated based on a global inventory of census-based SW and GW use compiled by the Food and Agricultural Organization (FAO). Our results suggest that irrigation could lead to two major opposing effects: SW depletion/GW accumulation in regions with irrigation primarily fed by SW, and SW accumulation/GW depletion in regions with irrigation fed primarily by GW. Furthermore, irrigation depending primarily on SW tends to have larger impacts on low-flow than high-flow conditions, suggesting the potential to increase vulnerability to drought. By the end of the 21st century (2070-2099), climate change significantly increases (relative to 1971-2000) irrigation water demand across the world. Combined with the increased temporal-spatial variability of water supply, this may lead to severe issues of local water scarcity for irrigation. Regionally, irrigation has the potential to aggravate/alleviate climate-induced changes of SW/GW although such effects are negligible when averaged globally. Our results emphasize the importance of accounting for irrigation effects and irrigation sources in regional climate change impact assessment.« less
Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; ...
2015-08-25
In this paper, the effects of irrigation on global surface water (SW) and groundwater (GW) resources are investigated by performing simulations using Community Land Model 4.0 (CLM4) at 0.5-degree resolution driven by downscaled/bias-corrected historical simulations and future projections from five General Circulation Models (GCMs) for 1950-2099. For each climate scenario, three sets of numerical experiments were configured: (1) a control experiment (CTRL) in which all crops are assumed to be rainfed; (2) an irrigation experiment (IRRIG) in which the irrigation module using only SW for irrigation is activated; and (3) a groundwater pumping experiment (PUMP) in which a groundwater pumpingmore » scheme coupled with the irrigation module is activated for conjunctive use of SW and GW for irrigation. The parameters associated with irrigation and groundwater pumping are calibrated based on a global inventory of census-based SW and GW use compiled by the Food and Agricultural Organization (FAO). Our results suggest that irrigation could lead to two major opposing effects: SW depletion/GW accumulation in regions with irrigation primarily fed by SW, and SW accumulation/GW depletion in regions with irrigation fed primarily by GW. Furthermore, irrigation depending primarily on SW tends to have larger impacts on low-flow than high-flow conditions, suggesting the potential to increase vulnerability to drought. By the end of the 21st century (2070-2099), climate change significantly increases (relative to 1971-2000) irrigation water demand across the world. Combined with the increased temporal-spatial variability of water supply, this may lead to severe issues of local water scarcity for irrigation. Regionally, irrigation has the potential to aggravate/alleviate climate-induced changes of SW/GW although such effects are negligible when averaged globally. Our results emphasize the importance of accounting for irrigation effects and irrigation sources in regional climate change impact assessment.« less
Economic Impact of Water Allocation on Agriculture in the Lower Chattahoochee River Basin
NASA Technical Reports Server (NTRS)
Limaye, Ashutosh S.; Paudel, Krishna P.; Musleh, Fuad; Cruise, James F.; Hatch, L. Upton
2004-01-01
The relative value of irrigation water was assessed for three important crops (corn, cotton, and peanuts) grown in the southeastern United States. A decision tool was developed with the objective of allocating limited available water among competing crops in a manner that would maximize the economic returns to the producers. The methodology was developed and tested for a hypothetical farm located in Henry County, Alabama in the Chattahoochee river basin. Crop yield - soil moisture response functions were developed using Monte Carlo simulated data for cotton, corn, and peanuts. A hydrologic model was employed to simulate runoff over the period of observed rainfall the county to provide inflows to storage facilities that could be used as constraints for the optimal allocation of the available water in the face of the uncertainty of future rainfall and runoff. Irrigation decisions were made on a weekly basis during the critical water deficit period in the region. An economic optimization model was employed with the crop responses, and soil moisture functions to determine the optimum amount of water place on each crop subject to the amount of irrigation water availability and climatic uncertainty. The results indicated even small amounts of irrigation could significantly benefit farmers in the region if applied judiciously. A weekly irrigation sequence was developed that maintained the available water on the crops that exhibited the most significant combination of water sensitivity and cash value.
Estimated Water Use in Puerto Rico, 2005
Molina-Rivera, Wanda L.; Gómez-Gómez, Fernando
2008-01-01
Water-use data were compiled for the 78 municipios of the Commonwealth of Puerto Rico for 2005. Five offstream categories were considered: public-supply water withdrawals and deliveries, domestic self-supplied water use, industrial self-supplied ground-water withdrawals, crop irrigation water use, and thermoelectric power freshwater use. One water-use category also was considered: power-generation instream water use (thermoelectric-saline withdrawals and hydroelectric power). Freshwater withdrawals and deliveries for offstream use from surface- and ground-water sources in Puerto Rico were estimated at 712 million gallons per day (Mgal/d). The largest amount of freshwater withdrawn was by public-supply water facilities and was estimated at 652 Mgal/d. The public-supply domestic water use was estimated at 347 Mgal/d. Fresh surface- and ground-water withdrawals by domestic self-supplied users were estimated at 2.1 Mgal/d and the industrial self-supplied withdrawals were estimated at 9.4 Mgal/d. Withdrawals for crop irrigation purposes were estimated at 45.2 Mgal/d, or approximately 6.3 percent of all offstream freshwater withdrawals. Instream freshwater withdrawals by hydroelectric facilities were estimated at 568 Mgal/d and saline instream surface-water withdrawals for cooling purposes by thermoelectric-power facilities was estimated at 2,288 Mgal/d.
NASA Astrophysics Data System (ADS)
Cooper, Harry J.; Smith, Eric A.; Martsolf, J. David
1997-02-01
Observations taken by two surface radiation and energy budget stations deployed in the University of Florida/Institute for Food and Agricultural Service experimental citrus orchard in Gainesville, Florida, have been analyzed to identify the effects of sprayer irrigation on thermal stability and circulation processes within the orchard during three 1992 winter freeze episodes. Lapse rates of temperature observed from a micrometeorological tower near the center of the orchard were also recorded during periods of irrigation for incorporation into the analysis. Comparisons of the near-surface temperature lapse rates observed with the two energy budget stations show consistency between the two sites and with the tower-based lapse rates taken over a vertical layer from 1.5 to 15 m above ground level. A theoretical framework was developed that demonstrates that turbulent-scale processes originating within the canopy, driven by latent heat release associated with condensation and freezing processes from water vapor and liquid water released from sprayer nozzles, can destabilize lapse rates and promote warm air mixing above the orchard canopy. The orchard data were then analyzed in the context of the theory for evidence of local overturning and displacement of surface-layer air, with warmer air from aloft driven by locally buoyant plumes generated by water vapor injected into the orchard during the irrigation periods. It was found that surface-layer lapse rates were lower during irrigation periods than under similar conditions when irrigation was not occurring, indicating a greater degree of vertical mixing of surface-layer air with air from above treetops, as a result of local convective overturning induced by the condensation heating of water vapor released at the nozzles of the sprinklers. This provides an additional explanation to the well-accepted heat of fusion release effect, of how undertree irrigation of a citrus orchard during a freeze period helps protect crops against frost damage.
Implications of salinity pollution hotspots on agricultural production
NASA Astrophysics Data System (ADS)
Floerke, Martina; Fink, Julia; Malsy, Marcus; Voelker, Jeanette; Alcamo, Joseph
2016-04-01
Salinity pollution can have many negative impacts on water resources used for drinking, irrigation, and industrial purposes. Elevated concentrations of salinity in irrigation water can lead to decreased crop production or crop death and, thus, causing an economic problem. Overall, salinity pollution is a global problem but tends to be more severe in arid and semi-arid regions where the dilution capacity of rivers and lakes is lower and the use of irrigation higher. Particularly in these regions agricultural production is exposed to high salinity of irrigation water as insufficient water quality further reduces the available freshwater resources. According to the FAO, irrigated agriculture contributes about 40 percent of the total food production globally, and therefore, high salinity pollution poses a major concern for food production and food security. We use the WaterGAP3 modeling framework to simulate hydrological, water use, and water quality conditions on a global scale for the time period 1990 to 2010. The modeling framework is applied to simulate total dissolved solids (TDS) loadings and in-stream concentrations from different point and diffuse sources to get an insight on potential environmental impacts as well as risks to agricultural food production. The model was tested and calibrated against observed data from GEMStat and literature sources. Although global in scope, the focus of this study is on developing countries, i.e., in Africa, Asia, and Latin America, as these are most threatened by salinity pollution. Furthermore, insufficient water quality for irrigation and therefore restrictions in irrigation water use are examined, indicating limitations to crop production. Our results show that elevated salinity concentrations in surface waters mainly occur in peak irrigation regions as irrigated agriculture is not only the most relevant water use sector contributing to water abstractions, but also the dominant source of salinity pollution. Additionally, large metropolitan regions are initially loading hotspots and pollution, too, and prevention becomes important as point sources are dependent on sewer connection rates and treatment levels. In conclusion, this study provides a detailed picture of the spatial and temporal distribution of salinity pollution and identifies hotspot areas as well as the dominant sources. Furthermore, impacts of water quality degradation on agricultural production and food security are quantified, which aim for a better understanding of the risks for food security caused by water quality impairment.
Research on the autumn irrigation schedule of Hetao Irrigation District of China
NASA Astrophysics Data System (ADS)
Han, Y.
2016-12-01
Salinization of soil has great influence on the function of crop land, leading to the crop failure to some extent. One of the inducement of salinization is that the water pressure of frozen soil is lower than that of unfrozen, salt is drew up to the frozen layer along with water during the freezing process. To prevent the salinization of soil, people carry out the autumn irrigation in Hetao Irrigation District which located is located in Bayannur City, Inner Mongolia, north of China. Autumn irrigation is an irrigation event before the freezing of soil, the function of autumn irrigation includes soil moisture conservation, loosening the soil and leaching the salt. Among all the crop models, none is designed to simulate the water and salt movement during freezing and thawing progress. So In this study, SWAP (Soil Water Atmosphere Plant) model is modified by adding the freezing and thawing module which enable the model to take into consideration the effect of freezing and thawing on water and salt movement. After validating the modified model using field data and lab test results, the model was used to simulate the results of various autumn irrigation schedules, exploring the influence of different autumn irrigation amounts on the water, salt and heat condition and transportation of soil. Finally, proper autumn irrigation schedule was obtained to instruct the production of Hetao Irrigation District.
Water resources in the Big Lost River Basin, south-central Idaho
Crosthwaite, E.G.; Thomas, C.A.; Dyer, K.L.
1970-01-01
The Big Lost River basin occupies about 1,400 square miles in south-central Idaho and drains to the Snake River Plain. The economy in the area is based on irrigation agriculture and stockraising. The basin is underlain by a diverse-assemblage of rocks which range, in age from Precambrian to Holocene. The assemblage is divided into five groups on the basis of their hydrologic characteristics. Carbonate rocks, noncarbonate rocks, cemented alluvial deposits, unconsolidated alluvial deposits, and basalt. The principal aquifer is unconsolidated alluvial fill that is several thousand feet thick in the main valley. The carbonate rocks are the major bedrock aquifer. They absorb a significant amount of precipitation and, in places, are very permeable as evidenced by large springs discharging from or near exposures of carbonate rocks. Only the alluvium, carbonate rock and locally the basalt yield significant amounts of water. A total of about 67,000 acres is irrigated with water diverted from the Big Lost River. The annual flow of the river is highly variable and water-supply deficiencies are common. About 1 out of every 2 years is considered a drought year. In the period 1955-68, about 175 irrigation wells were drilled to provide a supplemental water supply to land irrigated from the canal system and to irrigate an additional 8,500 acres of new land. Average. annual precipitation ranged from 8 inches on the valley floor to about 50 inches at some higher elevations during the base period 1944-68. The estimated water yield of the Big Lost River basin averaged 650 cfs (cubic feet per second) for the base period. Of this amount, 150 cfs was transpired by crops, 75 cfs left the basin as streamflow, and 425 cfs left as ground-water flow. A map of precipitation and estimated values of evapotranspiration were used to construct a water-yield map. A distinctive feature of the Big Lost River basin, is the large interchange of water from surface streams into the ground and from the ground into the surface streams. Large quantities of water disappear in the Chilly, Darlington, and other sinks and reappear above Mackay Narrows, above Moore Canal heading, and in other reaches. A cumulative summary of water yield upstream from selected points in the basin is as follows : Above Howell Ranch: water yield: 345 cfs; surface water: 310 cfs; ground water: 35 cfs Above. Mackay Narrows water yield: 450 cfs; surface water: 325 cfs; ground water: 75 cfs; crop evapotranspiration: 50 cfs Above Arco: water yield: 650 cfs; surface water: 75 cfs; ground water: 425 cfs; crop evapotranspiration: 150 cfs Ground-water pumping affects streamflow in reaches , where the stream and water table are continuous, but the effects of pumping were not measured except locally. Pumping depletes the total water supply by the. amount of the pumped water that is evapotranspired by crops. The part of the pumped water that is not consumed percolates into the ground or runs off over the land surface to the stream. The estimated 425 cfs that leaves the basin as ground-water flow is more than adequate for present and foreseeable needs. However because much of the outflow occurs at considerable depth, the quantity that is salvageable is unknown. Both the surface and ground waters are of good quality and are suitable for most uses. Although these waters are low in total dissolved solids, they tend to be hard or very hard.
Detecting crop yield reduction due to irrigation-induced soil salinization in South-West Russia
NASA Astrophysics Data System (ADS)
Argaman, E.; Beets, W.; Croes, J.; Keesstra, S.; Verzandvoort, S.; Zeiliguer, A.
2012-04-01
The South-European part of the Russian Federation has experienced serious land degradation in the form of soil salinization since the 1960s. This land degradation was caused by intensive, large-scale irrigation on reclaimed land in combination with the salt-rich nature of the substrate. Alkaline soil salinity is believed to be an important factor decreasing crop yield in this area. A large research effort has been directed to the effects of soil salinity on crops, there is a need for simple, easily determinable indicators of crop health and soil salinity in irrigated systems, that can help to detect crop water stress in an early stage. The objectives of this research were to study the effects of soil salinity and vegetation water stress on the performance of alfalfa crop yield and physiological crop properties, and to study the possibility to measure soil salinity and alkalinity and the crop water stress index at plot level using a thermal gun and a regular digital camera. The study area was located in Saratov District, in the South-West part of Russia. Variables on the surface energy balance, crop properties, soil properties and visible reflectance were measured on plots with alfalfa cultures in two fields with and without signs of alkaline soil salinity, and with and without irrigation in July 2009. The research showed no clear adverse effects of soil salinity and soil alkalinity on crop yield and physiological crop properties. Soil salinity, as reflected by the electric conductivity, positively affected the root biomass of alfalfa in the range of 0.15 to 1.52 dS/m . This was a result of EC levels being below the documented threshold to negatively affect Alfalfa, as would be the case in truly saline soils. The soil pH also showed a positive correlation with root biomass within the range of pH 6.2 and 8.5 . From the literature these pH values are generally believed to be too high to exhibit a positive relationship with root biomass. No relationship was found between EC and pH on the one hand , and soil moisture content on the other. However, soil moisture content in the topsoil appeared to have a major influence on the crop water stress index, which on its turn affected the leaf area index, the fresh biomass and the mean plant height. The crop leaf color as detected by a regular digital camera appeared to be correlated with pH and EC properties of the soil. The visible light band ratios red/green and blue/green correlated well with the crop water stress index. More research is necessary to prove if this relation is applicable in different environments, and for different crops. A confirmation of these findings would offer scope to increase the spatial support of this technique using satellite images.
Tillage and Irrigation Management of Cotton in a Corn/Cotton Rotation
USDA-ARS?s Scientific Manuscript database
A research study was undertaken to evaluate the yield of cotton in a corn-cotton rotation under two tillage treatments, conventional and minimum/conservation, and two irrigation treatments, irrigated and non-irrigated. Crops were grown under four treatments, irrigated-conventional tillage, irrigate...
NASA Astrophysics Data System (ADS)
Yang, Yan-min; Yang, Yonghui; Han, Shu-min; Hu, Yu-kun
2009-07-01
Hebei Plain is the most important agricultural belt in North China. Intensive irrigation, low and uneven precipitation have led to severe water shortage on the plain. This study is an attempt to resolve this crucial issue of water shortage for sustainable agricultural production and water resources management. The paper models distributed regional irrigation requirement for a range of cultivated crops on the plain. Classic crop models like DSSAT- wheat/maize and COTTON2K are used in combination with pan-evaporation coefficient method to estimate water requirements for wheat, corn, cotton, fruit-trees and vegetables. The approach is more accurate than the static approach adopted in previous studies. This is because the combination use of crop models and pan-evaporation coefficient method dynamically accounts for irrigation requirement at different growth stages of crops, agronomic practices, and field and climatic conditions. The simulation results show increasing Required Irrigation Amount (RIA) with time. RIA ranges from 5.08×109 m3 to 14.42×109 m3 for the period 1986~2006, with an annual average of 10.6×109 m3. Percent average water use by wheat, fruit trees, vegetable, corn and cotton is 41%, 12%, 12%, 11%, 7% and 17% respectively. RIA for April and May (the period with the highest irrigation water use) is 1.78×109 m3 and 2.41×109 m3 respectively. The counties in the piedmont regions of Mount Taihang have high RIA while the central and eastern regions/counties have low irrigation requirement.
Developing a global crop model for maize, wheat, and soybean production
NASA Astrophysics Data System (ADS)
Deryng, D.; Ramankutty, N.; Sacks, W. J.
2008-12-01
Recently, the world food supply has faced a crisis due to increasing food prices driven by rising food demand, increasing fuel prices, poor harvests due to climate factors, and the use of crops such as maize and soybean to produce biofuel. In order to assess the future of global food availability, there is a need for understanding the factors underlying food production. Farmer management practices along with climatic conditions are the main elements directly influencing crop yield. As a consequence, estimations of future world food production require the use of a global crop model that simulates reasonably the effect of both climate and management practices on yield. Only a few global crop models have been developed to date, and currently none of them represent management factors adequately, principally due to the lack of spatially explicit datasets at the global scale. In this study, we present a global crop model designed for maize, wheat, and soybean production that incorporates planting and harvest decisions, along with irrigation options based on newly available data. The crop model is built on a simple water-balance algorithm based on the Penman- Monteith equation combined with a light use efficiency approach that calculates biomass production under non-nutrient-limiting conditions. We used a world crop calendar dataset to develop statistical relationships between climate variables and planting dates for different regions of the world. Development stages are defined based on total growing degree days required to reach the beginning of each phase. Irrigation options are considered in regions where water stress occurs and irrigation infrastructures exist. We use a global dataset on irrigated areas for each crop type. The quantity of water applied is then calculated in order to avoid water stress but with an upper threshold derived from total irrigation withdrawal quantity estimated by the global water use model WaterGAP 2. Our analysis will present the model sensitivity to different scenarios of management practices, e.g. planting date and water supply, under non-nutrient limited conditions. With this study, we hope to clarify the importance of planting date and irrigation versus climate for crop yield.
NASA Astrophysics Data System (ADS)
Hama, Takehide; Aoki, Takeru; Osuga, Katsuyuki; Nakamura, Kimihito; Sugiyama, Sho; Kawashima, Shigeto
Implementation of collective crop rotation in a paddy-field district may increase nutrients effluent load. We have investigated a paddy-field district implementing collective crop rotation of wheat and soybeans, measured temporal variations in nutrients concentration of drainage water and the amount of discharged water for consecutive three years, and estimated nutrients effluent load from the district during the irrigation and non-irrigation periods. As a result, the highest concentration of nutrients was observed during the non-irrigation period in every investigation year. It was shown that high nutrients concentration of drainage water during the non-irrigation period was caused by runoff of fertilizer applied to wheat because the peaks of nutrients concentration of drainage water were seen in rainy days after fertilizer application in the crop-rotation field. The effluent load during the non-irrigation periods was 16.9-22.1 kgN ha-1 (nitrogen) and 0.84-1.42 kgP ha-1 (phosphorus), which respectively accounted for 46-66% and 27-54% of annual nutrients effluent load.
Fanning, Julia L.; Schwarz, Gregory E.; Lewis, William C.
2001-01-01
A benchmark irrigation monitoring network of farms located in a 32-county area in southwestern Georgia was established in 1995 to improve estimates of irrigation water use. A stratified random sample of 500 permitted irrigators was selected from a data base--maintained by the Georgia Department of Natural Resources, Georgia Environmental Protection Division, Water Resources Management Branch--to obtain 180 voluntary participants in the study area. Site-specific irrigation data were collected at each farm using running-time totalizers and noninvasive flowmeters. Data were collected and compiled for 50 farms for 1995 and 130 additional farms for the 1996 growing season--a total of 180 farms. Irrigation data collected during the 1996 growing season were compiled for 180 benchmark farms and used to develop a statistical model to estimate irrigation water use in 32 counties in southwestern Georgia. The estimates derived were developed from using a statistical approach know as "bootstrap analysis" that allows for the estimation of precision. Five model components--whether-to-irrigate, acres irrigated, crop selected, seasonal-irrigation scheduling, and the amount of irrigation applied--compose the irrigation model and were developed to reflect patterns in the data collected at Benchmark Farms Study area sites. The model estimated that peak irrigation for all counties in the study area occurred during July with significant irrigation also occurring during May, June, and August. Irwin and Tift were the most irrigated and Schley and Houston were the least irrigated counties in the study area. High irrigation intensity primarily was located along the eastern border of the study area; whereas, low irrigation intensity was located in the southwestern quadrant where ground water was the dominant irrigation source. Crop-level estimates showed sizable variations across crops and considerable uncertainty for all crops other than peanuts and pecans. Counties having the most irrigated acres showed higher variations in annual irrigation than counties having the least irrigated acres. The Benchmark Farms Study model estimates were higher than previous irrigation estimates, with 20 percent of the bias a result of underestimating irrigation acreage in earlier studies. Model estimates showed evidence of an upward bias of about 15 percent with the likely cause being a misrepresented inches-applied model. A better understanding of the causes of bias in the model could be determined with a larger irrigation sample size and increased substantially by automating the reporting of monthly totalizer amounts.
Biofuel as an Integrated Farm Drainage Management crop: A bioeconomic analysis
NASA Astrophysics Data System (ADS)
Levers, L. R.; Schwabe, K. A.
2017-04-01
Irrigated agricultural lands in arid regions often suffer from soil salinization and lack of drainage, which affect environmental quality and productivity. Integrated Farm Drainage Management (IFDM) systems, where drainage water generated from higher-valued crops grown on high quality soils are used to irrigate salt-tolerant crops grown on marginal soils, is one possible strategy for managing salinity and drainage problems. If the IFDM crop were a biofuel crop, both environmental and private benefits may be generated; however, little is known about this possibility. As such, we develop a bioeconomic programming model of irrigated agricultural production to examine the role salt-tolerant biofuel crops might play within an IFDM system. Our results, generated by optimizing profits over land, water, and crop choice decisions subject to resource constraints, suggest that based on the private profits alone, biofuel crops can be a competitive alternative to the common practices of land retirement and nonbiofuel crop production under both low to high drainage water salinity. Yet IFDM biofuel crop production generates 30-35% fewer GHG emissions than the other strategies. The private market competitiveness coupled with the public good benefits may justify policy changes encouraging the growth of IFDM biofuel crops in arid agricultural areas globally.
Irmak, A.; Singh, Ramesh K.; Walter-Shea, Elizabeth; Verma, S.B.; Suyker, A.E.
2011-01-01
We evaluated the performance of four models for estimating soil heat flux density (G) in maize (Zea mays L.) and soybean (Glycine max L.) fields under different irrigation methods (center-pivot irrigated fields at Mead, Nebraska, and subsurface drip irrigated field at Clay Center, Nebraska) and rainfed conditions at Mead. The model estimates were compared against measurements made during growing seasons of 2003, 2004, and 2005 at Mead and during 2005, 2006, and 2007 at Clay Center. We observed a strong relationship between the G and net radiation (Rn) ratio (G/Rn) and the normalized difference vegetation index (NDVI). When a significant portion of the ground was bare soil, G/Rn ranged from 0.15 to 0.30 and decreased with increasing NDVI. In contrast to the NDVI progression, the G/Rn ratio decreased with crop growth and development. The G/Rn ratio for subsurface drip irrigated crops was smaller than for the center-pivot irrigated crops. The seasonal average G was 13.1%, 15.2%, 10.9%, and 12.8% of Rn for irrigated maize, rainfed maize, irrigated soybean, and rainfed soybean, respectively. Statistical analyses of the performance of the four models showed a wide range of variation in G estimation. The root mean square error (RMSE) of predictions ranged from 15 to 81.3 W m-2. Based on the wide range of RMSE, it is recommended that local calibration of the models should be carried out for remote estimation of soil heat flux.
Using Remote Sensing to Determine Timing of High Altitude Grass Hay Growth Stages
NASA Astrophysics Data System (ADS)
Mefford, B.
2015-12-01
Remote sensing has become the standard for collecting data to determine potential irrigation consumptive use in Wyoming for the Green River Basin. The Green River Basin within Wyoming is around 10.8 million acres, located in south western Wyoming and is a sub-basin of the Colorado River Basin. Grass hay is the main crop grown in the basin. The majority of the hay is grown at elevations 7,000 feet above mean sea level. Daily potential irrigation consumptive use is calculated for the basin during the growing season (May 1st to September 30th). To determine potential irrigation consumptive use crop coefficients, reference evapotranspiration (ET) and effective precipitation are required. Currently crop coefficients are the hardest to determine as most research on crop coefficients are based at lower elevations. Values for crop coefficients for grass hay still apply to high altitude grass hay, but the hay grows at a much slower rate than low elevation grass hay. To be able to more accurately determine the timing of the growth stages of hay in this basin, time-lapse cameras were installed at two different irrigated hay fields in the basin for the 2015 growing season and took pictures automatically once a day at 1 P.M.. Both of the fields also contained a permanent research grade weather station. Imagery obtained from these cameras was used as indicators of timing of the major growth stages of the hay and the length of days between the stages. A crop coefficient value was applied every day in the growing season based on the results from the imagery. Daily potential ET was calculated using the crop coefficients and the data from the on-site weather stations. The final result was potential irrigation induced crop consumptive use for each site. Using remote sensing provided necessary information that normally would be applied arbitrarily in determining irrigation induced consumptive use in the Green River Basin.
NASA Astrophysics Data System (ADS)
Rigby, J.; Haugh, C. J.; Barlow, J.
2015-12-01
The Lower Mississippi River Basin is one of the major agricultural production regions in the United States producing over two-thirds of the rice, nearly half of sugarcane produced in the U.S., as well as significant amounts of soybeans, corn, and cotton. While the region experiences over 50 inches of precipitation annually, reaching yield potential for crops requires irrigation. Approximately 75% of crop acres in the alluvial valley are irrigated, and the expectation is that all acreage will eventually be irrigated. Currently over 90% of water for crop irrigation is derived from the shallow alluvial aquifer outpacing net recharge by several million acre-feet per year. This has resulted in severe groundwater declines in Arkansas and an increasingly threatening situation in northwestern Mississippi. In Mississippi, direct injection has received increasing attention as a means of artificial recharge, though water quality remains a concern both for the integrity of the aquifer and efficiency of injection. This project considers the use of pumping wells near major rivers known to be in connection with the aquifer to induce additional infiltration of surface water by steepening local gradients. The pumped water would be transferred by pipeline to areas within the regional cone of depression where it is then injected to enhance groundwater recharge. Groundwater flow modeling with zone budget analysis is used to evaluate the potential for net supply gains from induced infiltration at potential sites along major rivers in the region. The groundwater model will further evaluate the impact of the transfer and direct injection on regional water tables.
The Value of Weather Forecast in Irrigation
NASA Astrophysics Data System (ADS)
Cai, X.; Wang, D.
2007-12-01
This paper studies irrigation scheduling (when and how much water to apply during the crop growth season) in the Havana Lowlands region, Illinois, using meteorological, agronomic and agricultural production data from 2002. Irrigation scheduling determines the timing and amount of water applied to an irrigated cropland during the crop growing season. In this study a hydrologic-agronomic simulation is coupled with an optimization algorithm to search for the optimal irrigation schedule under various weather forecast horizons. The economic profit of irrigated corn from an optimized scheduling is compared to that from and the actual schedule, which is adopted from a pervious study. Extended and reliable climate prediction and weather forecast are found to be significantly valuable. If a weather forecast horizon is long enough to include the critical crop growth stage, in which crop yield bears the maximum loss over all stages, much economic loss can be avoided. Climate predictions of one to two months, which can cover the critical period, might be even more beneficial during a dry year. The other purpose of this paper is to analyze farmers' behavior in irrigation scheduling by comparing the "actual" schedule to the "optimized" ones. The ultimate goal of irrigation schedule optimization is to provide information to farmers so that they may modify their behavior. In practice, farmers' decision may not follow an optimal irrigation schedule due to the impact of various factors such as natural conditions, policies, farmers' habits and empirical knowledge, and the uncertain or inexact information that they receive. In this study farmers' behavior in irrigation decision making is analyzed by comparing the "actual" schedule to the "optimized" ones. This study finds that the identification of the crop growth stage with the most severe water stress is critical for irrigation scheduling. For the case study site in the year of 2002, framers' response to water stress was found to be late; they did not even respond appropriately to a major rainfall just 3 days ahead, which might be due to either an unreliable weather forecast or farmer's ignorance of the forecast.
NASA Astrophysics Data System (ADS)
Rodrigues, Lineu; Marioti, Juliana; Steenhuis, Tammo; Wallender, Wesley
2010-05-01
Irrigated agriculture is the major consumer of surface water in Brazil using over 70% of the total supply. Due to the growing competition for water among different sectors of the economy, sustainable water use can only be achieved by decreasing the portion of water used by the irrigated agriculture. Thus, in order to maintain yield, farmers need to irrigate more efficiently. There is little known on irrigation efficiency in Brazil. Therefore a study was carried out in the Buriti Vermelho basin to assess the irrigation performance of existing system. The experimental basin has a drainage area of 940 hectares and is located in the eastern part of the Federal District, in the Brazilian savanna region. Agriculture is the main activity. There is a dominance of red latosols. Several types of land use and crop cover are encountered in the basin. Conflicts among farmers for water are increasing. As water, in quality and quantity, is crucial to maintain the livelihood of the population in the basin, concern about risk of water lack due to climatic and land use change is in place. Once irrigation is the main water user in the basin, to increase water availability and reduce conflicts a water resource management plan has to be established. For this purpose, irrigation system performance has to be understood. The objective of this work was to assess the performance and the management of irrigation (small and big) that has been carried out by farmers in the Buriti Vermelho experimental watershed. A survey undertaken in 2007 was used to identify the irrigation systems in the basin. It was verified that irrigation is practiced by both small (area up to 6 hectare) and big farmers. Small farmers usually crop limes and vegetables and use micro-irrigation, drip, sprinkler, guns or furrow to irrigate them. Big farmers plant annual crops and use center pivot as irrigation system. In this first assessment 13 irrigation systems were evaluated: five conventional sprinklers, four drip systems, one microirrigation system and three center pivots schemes. Field evaluations used the method advocated by Keller and Bliesner and conducted during farmer scheduled irrigation. Soil samples were taken before irrigations to investigate adequacy of water applied. Since the irrigation water management and the uniformity of water distribution are the two major factors used to define the quality of irrigation, the following criteria for uniformity was used: i) Localized irrigations (distribution uniformity - UD) - excellent (90% < UD), acceptable (70% < UD < 90%), not acceptable (UD < 70); ii) Center pivots and conventional sprinkler irrigations (Christiansen coefficient - UC) - excellent (85% < UC), acceptable (85% < UC < 75%), not acceptable (UC < 75%). The water stored in the root zone after an irrigation event was compared with the real necessity. The results showed that: i) Localized irrigations - Three systems had UD < 70% and all systems presented deficit or excess of irrigation; ii) Conventional sprinkler system - Three system had UD smaller than 75% and all systems applied less water than the minimum necessary to keep an amount of water in the soil that don't cause plant stress; iii) Center pivot - In two system were observed UC < 75%. In one of the center pivots the depth applied was about 42% higher than the required and in the other two it was 39% and 47% lower. The study demonstrated the importance of adopting irrigation management criteria, in agricultural basins, once irrigation water becomes limiting and reduces basin water productivity.
NASA Astrophysics Data System (ADS)
Bernstein, N.
2009-04-01
The use of wastewater for agricultural irrigation is steadily increasing world-wide and due to shortages of fresh water is common today in most arid regions of the world. The use of treated wastewater for agricultural irrigation may result in soil exposure to pathogens, creating potential public health problems. A variety of human pathogens are present in raw sewage water. Although their concentrations decrease during the wastewater reclamation process, the secondary treated effluents most commonly used for irrigation today still contain bacterial human pathogens. A range of bacterial pathogens, introduced through contaminated irrigation water or manure, are capable of surviving for long periods in soil and water where they have the potential to contaminate crops in the field. Therefore, there is a risk of direct contamination of crops by human pathogens from the treated effluents used for irrigation, as well as a risk of indirect contamination of the crops from contaminated soil at the agricultural site. Contradictory to previous notion, recent studies have demonstrated that human pathogens can enter plants through their roots and translocate and survive in edible, aerial plant tissues. The practical implications of these new findings for food safety are still not clear, but no doubt reflect the pathogenic microorganisms' ability to survive and multiply in the irrigated soil, water, and the harvested edible crop.
AmeriFlux US-Ne1 Mead - irrigated continuous maize site
Suyker, Andy [University of Nebraska - Lincoln
2016-01-01
This is the AmeriFlux version of the carbon flux data for the site US-Ne1 Mead - irrigated continuous maize site. Site Description - The study site is one of three fields (all located within 1.6 km of each other) at the University of Nebraska Agricultural Research and Development Center near Mead, Nebraska. This site is irrigated with a center pivot system. Prior to the initiation of the study, the irrigated site had a 10-yr history of maize-soybean rotation under no-till. A tillage operation (disking) was done just prior to the 2001 planting to homogenize the top 0.1 m of soil, incorporate P and K fertilizers, as well as previously accumulated surface residues. Since the tillage operation, the site has been under no-till management until the harvest of 2005. Following harvest, a conservation-plow tillage operation was initiated where a small amount of N fertilizer is sprayed on the residue immediately prior to the plow operation. Approximately 1/3 of the crop residue is left on the surface. The post-harvest conservation-plow operation continues as the current practice.
Marella, Richard L.; Dixon, Joann F.; Berry, Darbi R.
2016-07-28
The irrigated acreage that was field verified in 2015 for the 13 counties in the Suwannee River Water Management District (113,134 acres) is about 6 percent higher than the estimated acreage published by the U.S. Department of Agriculture (107,217 acres) for 2012; however, this 2012 value represents acreage for the entire portion of all 13 counties, not just the Suwannee River Water Management District portion. Differences between the 2015 field-verified acreage totals and those published by the U.S. Department of Agriculture for 2012 may occur because (1) irrigated acreage for some specific crops increased or decreased substantially during the 3-year interval due to commodity prices or economic changes, (2) calculated field-verified irrigated acreage may be an overestimate because irrigation was assumed if an irrigation system was present and therefore the acreage was counted as irrigated, when in fact that may not have been the case as some farmers may not have used their irrigation systems during this growing period even if they had a crop in the field, or (3) the amount of irrigated acreages published by the U.S. Department of Agriculture for selected crops may be underestimated in some cases.
NASA Astrophysics Data System (ADS)
Multsch, S.; Exbrayat, J.-F.; Kirby, M.; Viney, N. R.; Frede, H.-G.; Breuer, L.
2014-11-01
Irrigation agriculture plays an increasingly important role in food supply. Many evapotranspiration models are used today to estimate the water demand for irrigation. They consider different stages of crop growth by empirical crop coefficients to adapt evapotranspiration throughout the vegetation period. We investigate the importance of the model structural vs. model parametric uncertainty for irrigation simulations by considering six evapotranspiration models and five crop coefficient sets to estimate irrigation water requirements for growing wheat in the Murray-Darling Basin, Australia. The study is carried out using the spatial decision support system SPARE:WATER. We find that structural model uncertainty is far more important than model parametric uncertainty to estimate irrigation water requirement. Using the Reliability Ensemble Averaging (REA) technique, we are able to reduce the overall predictive model uncertainty by more than 10%. The exceedance probability curve of irrigation water requirements shows that a certain threshold, e.g. an irrigation water limit due to water right of 400 mm, would be less frequently exceeded in case of the REA ensemble average (45%) in comparison to the equally weighted ensemble average (66%). We conclude that multi-model ensemble predictions and sophisticated model averaging techniques are helpful in predicting irrigation demand and provide relevant information for decision making.
NASA Astrophysics Data System (ADS)
Senay, G. B.; Schauer, M.; Friedrichs, M.; Velpuri, N. M.; Singh, R. K.
2016-12-01
Remote sensing-based field scale evapotranspiration (ET) maps are useful for characterizing water use patterns and assessing crop performance. Historical (1984-2014) Landsat-based ET maps were generated for major irrigation districts in the southwestern US. A total of 3,396 Landsat images were processed using the Operational Simplified Surface Energy balance (SSEBop) model that integrates weather and remotely sensed images to estimate monthly and annual ET within the study areas over the 31 years. Model output evaluation and validation using point-based eddy covariance flux tower, gridded-flux data and water balance ET approaches indicated relatively strong association between SSEBop ET and validation datasets. Historical trend analysis of seven agro-hydrologic variables using the Seasonal Mann-Kendall test showed interesting results. In a pair wise comparison, management influenced variables such as actual evapotranspiration (ETa), land surface temperature (Ts) and runoff (Q) were found to be more variable than their corresponding climate counterparts of atmospheric water demand (ETo), air temperature (Ta) and precipitation, responding to the impacts of management decisions. Our results indicated that only air temperature showed a consistent increase (up to 1.2 K) across all 9 irrigation sub-basins during the 31 years. District-wide ETa estimates were used to compute historical crop water use volumes and monetary savings for the Palo Verde Irrigation district (PVID). During the peak crop fallowing program in PVID, the water savings reached a maximum of 85,000 ac-ft per year which is equivalent to a dollar amount of $ 600 million. This study has many applications in planning water resource allocation, monitoring and assessing water usage and performance, and quantifying impacts of climate and land use/land cover changes on water resources. With increased computational efficiency and model development, similar studies can be conducted in other parts of the world.
Furrow Diking in Conservation Tillage
USDA-ARS?s Scientific Manuscript database
Crop production in the Southeastern U.S. can be limited by water; thus, supplemental irrigation is needed to sustain profitable crop production. Increased water capture would efficiently improve water use and reduce supplemental irrigation amounts/costs, thus improving producer’s profit margin. We q...
The Role of Windbreaks in Reducing Water Resources Use in Irrigated Agriculture
NASA Astrophysics Data System (ADS)
Cochrane, T. A.; de Vries, T. T.
2014-12-01
Windbreaks are common features in flat agricultural landscapes around the world. The reduction in wind speed afforded by windbreaks is dictated by their porosity, location, height, and distance from the windbreak. The reduction in wind speeds not only reduces potential wind erosion; it also reduces crop evapotranspiration (ET) and provides shelter for livestock and crops. In the Canterbury plains of New Zealand there are over 300,000 km of windbreaks which were first implemented as a soil conservation strategy to reduce wind erosion of prime agricultural land. Agriculture in the region has since changed to irrigated pasture cultivation for dairy production and windbreaks are being cut down or reduced to heights of 2 m to allow for large scale centre-pivot irrigation schemes. Although soil erosion is no longer a major concern due to permanent pasture cover, irrigation water is sourced from limited supplies of ground and surface water and thus the effects of wind on irrigation losses due to spray drift and increased ET are of significant concern. The impact of reducing windbreaks needs to be understood in terms of water resources use. Experimental and theoretical work was conducted to quantify the reduction in wind speeds by windbreaks and in spray evaporation losses. A temporal and spatial model was also developed and validated to quantify the impact of single and multiple windbreaks on irrigation water losses. Initial modelling results show that for hot windy dry conditions in Canterbury, ET can increase by up to 1.4 mm/day when windbreaks are reduced to 2 m in height and on average wind days ET can increase by up to 0.5 mm/day. ET can be reduced by up to 30% in the windbreak leeward zone relative to ET in areas not protected by windbreaks. Wind speed, air temperature and relative humidity all had a considerable impact on spray evaporation losses, but the extent is determined by the droplet size. Estimated losses range from only 0.07% to 67% for 5 and 0.2 mm droplet sizes respectively. Preliminary measurements of typical irrigation spray nozzles with a range of drop sizes show losses of up to 30% under high wind conditions. Potential reduction in ground and surface water resources use for irrigation can be significant if windbreaks are maintained by using irrigation systems that can be adapted to work within windbreaks.
Application of future remote sensing systems to irrigation
NASA Technical Reports Server (NTRS)
Miller, L. D.
1982-01-01
Area estimates of irrigated crops and knowledge of crop type are required for modeling water consumption to assist farmers, rangers, and agricultural consultants in scheduling irrigation for distributed management of crop yields. Information on canopy physiology and soil moisture status on a spatial basis is potentially available from remote sensors, so the questions to be addressed relate to: (1) timing (data frequency, instantaneous and integrated measurement); and scheduling (widely distributed spatial demands); (2) spatial resolution; (3) radiometric and geometric accuracy and geoencoding; and (4) information/data distribution. This latter should be overnight, with no central storage, onsite capture, and low cost.
Recent studies have shown the detection of pharmaceuticals in surface waters across the United States. The objective of this study was to develop methods, and apply them, to evaluate the potential for food chain transfer when pharmaceutical containing wastewaters are used for cr...
USDA-ARS?s Scientific Manuscript database
In 2008, a team of USDA and university researchers assembled to study the surface energy balance and associated energy and water fluxes within, below and above the internal boundary layers over irrigated and dryland cotton crops in the hot, windy and advective environment of the Texas Panhandle at B...
NASA Astrophysics Data System (ADS)
Multsch, S.; Al-Rumaikhani, Y. A.; Frede, H.-G.; Breuer, L.
2013-01-01
The water footprint accounting method addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). Most of current water footprint assessments focus on global to continental scale. We therefore developed the spatial decision support system SPARE:WATER that allows to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirement and water footprints are assessed on a grid-basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume in-efficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water can be defined as the water to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr-1 for 2008 with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional water footprint assessments.
NASA Technical Reports Server (NTRS)
Paudel, Krishna P.; Limaye, Ashutosh; Hatch, Upton; Cruise, James; Musleh, Fuad
2005-01-01
We developed a dynamic model to optimize irrigation application in three major crops (corn, cotton and peanuts) grown in the Southeast USA. Water supply amount is generated from an engineering model which is then combined with economic models to find the optimal amount of irrigation water to apply on each crop field during the six critical water deficit weeks in summer. Results indicate that water is applied on the crop with the highest marginal value product of irrigation. Decision making tool such as the one developed here would help farmers and policy makers to find the maximum profitable solution when water shortage is a serious concern.
Using a basin-scale hydrological model to estimate crop transpiration and soil evaporation
NASA Astrophysics Data System (ADS)
Kite, G.
2000-03-01
Increasing populations and expectations, declining crop yields and the resulting increased competition for water necesitate improvements in irrigation management and productivity. A key factor in defining agricultural productivity is to be able to simulate soil evaporation and crop transpiration. In agribusiness terms, crop transpiration is a useful process while soil and open-water evaporations are wasteful processes. In this study a distributed hydrological model was used to compute daily evaporation and transpiration for a variety of crops and other land covers within the 17,200 km 2 Gediz Basin in western Turkey. The model, SLURP, describes the complete hydrological cycle for each land cover within a series of sub-basins including all dams, reservoirs, regulators and irrigation schemes in the basin. The sub-basins and land covers are defined by analysing a digital elevation model and NOAA AVHRR satellite data. In this study, the model uses the FAO implementation of the Penman-Monteith equation to simulate soil evaporation and crop transpiration. The results of the model runs provide time series of data on streamflow at many points along the river system, abstractions and return flows from crops within the irrigation schemes and areally distributed soil evaporation and crop transpiration across the entire basin on each day of an 11 year period. The results show that evaporation and transpiration vary widely across the basin on any one day and over the irrigation season and can be used to evaluate the effectiveness of the various irrigation strategies used in the basin. The advantages of using such a model as compared to deriving evapotranspiration from satellite data are that the model obtains results for each day of an indefinitely long period, as opposed to occasional snapshots, and can also be used to simulate alternate scenarios.
Less water: How will agriculture in Southern Mountain states adapt?
NASA Astrophysics Data System (ADS)
Frisvold, George B.; Konyar, Kazim
2012-05-01
This study examined how agriculture in six southwestern states might adapt to large reductions in water supplies, using the U.S. Agricultural Resource Model (USARM), a multiregion, multicommodity agricultural sector model. In the simulation, irrigation water supplies were reduced 25% in five Southern Mountain (SM) states and by 5% in California. USARM results were compared to those from a "rationing" model, which assumes no input substitution or changes in water use intensity, relying on land fallowing as the only means of adapting to water scarcity. The rationing model also ignores changes in output prices. Results quantify the importance of economic adjustment mechanisms and changes in output prices. Under the rationing model, SM irrigators lose 65 in net income. Compared to this price exogenous, "land-fallowing only" response, allowing irrigators to change cropping patterns, practice deficit irrigation, and adjust use of other inputs reduced irrigator costs of water shortages to 22 million. Allowing irrigators to pass on price increases to purchasers reduced income losses further, to 15 million. Higher crop prices from reduced production imposed direct losses of 130 million on first purchasers of crops, which include livestock and dairy producers, and cotton gins. SM agriculture, as a whole, was resilient to the water supply shock, with production of high value specialty crops along the Lower Colorado River little affected. Particular crops were vulnerable however. Cotton production and net returns fell substantially, while reductions in water devoted to alfalfa accounted for 57% of regional water reduction.
NASA Astrophysics Data System (ADS)
Adhikari, B.; Verhoeven, R.; Troch, P.
The farmer managed irrigation systems (FMIS) represent those systems which are constructed and operated solely by the farmers applying their indigenous technology. The FMIS generally outperform the modern irrigation systems constructed and operated by the government agencies with regard to the water delivery effectiveness, agricultural productivity etc., and the presence of a sound organization responsible to run the FMIS, often referred to as the ‘social capital’, is the key to this success. This paper studies another important aspect residing in the FMIS: potentials to expand the irrigation area by means of their proper rehabilitation and modernization. Taking the case study of the Babai Irrigation Project in Nepal, it is demonstrated that the flow, which in the past was used to irrigate the 5400 ha area covered by three FMIS, can provide irrigation to an additional 8100 ha in the summer, 4180 ha vegetables in the winter and 1100 ha maize in the spring season after the FMIS rehabilitation. The “priority water rights” of the FMIS part have been evaluated based on relevant crop water requirement calculations and is found to be equal to 85.4 million m 3 per year. Consequently, the dry season irrigation strategy at the extension area could be worked out based on the remaining flow. By storing the surplus discharge of the monsoon and autumn in local ponds, and by consuming them in dry period combined with nominal partial irrigation practice, wheat and mustard can be cultivated over about 4000 ha of the extension area. Furthermore, storage and surface irrigation both contribute to the groundwater recharge. The conjunctive use of ground, surface and harvested water might be the mainstream in the future for a sustainable irrigation water management in the region.
Jin, Virginia L; Schmer, Marty R; Stewart, Catherine E; Sindelar, Aaron J; Varvel, Gary E; Wienhold, Brian J
2017-07-01
Over the last 50 years, the most increase in cultivated land area globally has been due to a doubling of irrigated land. Long-term agronomic management impacts on soil organic carbon (SOC) stocks, soil greenhouse gas (GHG) emissions, and global warming potential (GWP) in irrigated systems, however, remain relatively unknown. Here, residue and tillage management effects were quantified by measuring soil nitrous oxide (N 2 O) and methane (CH 4 ) fluxes and SOC changes (ΔSOC) at a long-term, irrigated continuous corn (Zea mays L.) system in eastern Nebraska, United States. Management treatments began in 2002, and measured treatments included no or high stover removal (0 or 6.8 Mg DM ha -1 yr -1 , respectively) under no-till (NT) or conventional disk tillage (CT) with full irrigation (n = 4). Soil N 2 O and CH 4 fluxes were measured for five crop-years (2011-2015), and ΔSOC was determined on an equivalent mass basis to ~30 cm soil depth. Both area- and yield-scaled soil N 2 O emissions were greater with stover retention compared to removal and for CT compared to NT, with no interaction between stover and tillage practices. Methane comprised <1% of total emissions, with NT being CH 4 neutral and CT a CH 4 source. Surface SOC decreased with stover removal and with CT after 14 years of management. When ΔSOC, soil GHG emissions, and agronomic energy usage were used to calculate system GWP, all management systems were net GHG sources. Conservation practices (NT, stover retention) each decreased system GWP compared to conventional practices (CT, stover removal), but pairing conservation practices conferred no additional mitigation benefit. Although cropping system, management equipment/timing/history, soil type, location, weather, and the depth to which ΔSOC is measured affect the GWP outcomes of irrigated systems at large, this long-term irrigated study provides valuable empirical evidence of how management decisions can impact soil GHG emissions and surface SOC stocks. © 2017 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Feltz, N.; Gaspart, F.; Vanclooster, M.
2015-12-01
In order to save agricultural water, the famous FAO's "more crop per drop" has been taken literally in many arid or semi-arid places around the world and policies that aim improving "efficiencies" (irrigation efficiency…) have been implemented, often leading to the promotion of water saving technologies. In 1865, studying coal consumption, W.S. Jevons highlighted that improving coal use efficiency could, as a paradox, lead to higher global coal use. Many economists later extended this idea to resource saving technologies in general, showing that, due to the "rebound effect", the adoption of more efficient technologies, in terms of use of resources, could lead to a higher global consumption of this resource if this adoption didn't go with adjustment measures. Regarding these considerations, the emerging question is to which extent water saving technologies (i.e. that aim improving water related efficiencies) are appropriate to save water at large scale. Our study addresses this question through the analysis of the conversion from surface to drip irrigation in Triffa's irrigated perimeter (Morocco). We aim addressing this question using the detailed analysis of two data sets. First, available data were collected for every farm within the study area from the local administrations. Second, interviews were conducted with farmers to complete the dataset and to characterize their behavior. This allowed assessing water related efficiencies at farm scale. Subsequently, models were implemented to link efficiencies with general attributes and thereby identify the main drivers of water related efficiencies in the study area. Finally, these models were used to upscale farm-scale assessment to the perimeter scale. Our results show that, under current conditions, moving from surface to drip irrigation leads to higher global water withdrawal. However, the aforementioned "rebound effect" does not allow explaining the higher pressure because of contextual specificities. Deeper analysis suggests that economic but also social and psychological issues need to be considered in this transition process. To fully achieve the expected results from moving to drip irrigation, those issues must be dealt with and the transition to drip irrigation must go hand in hand with stewardship programs and appropriate farmers capacity building.
Integrating Growth Stage Deficit Irrigation into a Process Based Crop Model
NASA Technical Reports Server (NTRS)
Lopez, Jose R.; Winter, Jonathan M.; Elliott, Joshua; Ruane, Alex C.; Porter, Cheryl; Hoogenboom, Gerrit
2017-01-01
Current rates of agricultural water use are unsustainable in many regions, creating an urgent need to identify improved irrigation strategies for water limited areas. Crop models can be used to quantify plant water requirements, predict the impact of water shortages on yield, and calculate water productivity (WP) to link water availability and crop yields for economic analyses. Many simulations of crop growth and development, especially in regional and global assessments, rely on automatic irrigation algorithms to estimate irrigation dates and amounts. However, these algorithms are not well suited for water limited regions because they have simplistic irrigation rules, such as a single soil-moisture based threshold, and assume unlimited water. To address this constraint, a new modeling framework to simulate agricultural production in water limited areas was developed. The framework consists of a new automatic irrigation algorithm for the simulation of growth stage based deficit irrigation under limited seasonal water availability; and optimization of growth stage specific parameters. The new automatic irrigation algorithm was used to simulate maize and soybean in Gainesville, Florida, and first used to evaluate the sensitivity of maize and soybean simulations to irrigation at different growth stages and then to test the hypothesis that water productivity calculated using simplistic irrigation rules underestimates WP. In the first experiment, the effect of irrigating at specific growth stages on yield and irrigation water use efficiency (IWUE) in maize and soybean was evaluated. In the reproductive stages, IWUE tended to be higher than in the vegetative stages (e.g. IWUE was 18% higher than the well watered treatment when irrigating only during R3 in soybean), and when rainfall events were less frequent. In the second experiment, water productivity (WP) was significantly greater with optimized irrigation schedules compared to non-optimized irrigation schedules in water restricted scenarios. For example, the mean WP across 38 years of maize production was 1.1 kg/cu m for non-optimized irrigation schedules with 50 mm of seasonal available water and 2.1 kg/cu m optimized ion schedules, a 91% improvement in WP with optimized irrigation schedules. The framework described in this work could be used to estimate WP for regional to global assessments, as well as derive location specific irrigation guidance.
NASA Astrophysics Data System (ADS)
Rajagopalan, K.; Chinnayakanahalli, K. J.; Stockle, C. O.; Nelson, R. L.; Kruger, C. E.; Brady, M. P.; Malek, K.; Dinesh, S. T.; Barber, M. E.; Hamlet, A. F.; Yorgey, G. G.; Adam, J. C.
2018-03-01
Adaptation to a changing climate is critical to address future global food and water security challenges. While these challenges are global, successful adaptation strategies are often generated at regional scales; therefore, regional-scale studies are critical to inform adaptation decision making. While climate change affects both water supply and demand, water demand is relatively understudied, especially at regional scales. The goal of this work is to address this gap, and characterize the direct impacts of near-term (for the 2030s) climate change and elevated CO2 levels on regional-scale crop yields and irrigation demands for the Columbia River basin (CRB). This question is addressed through a coupled crop-hydrology model that accounts for site-specific and crop-specific characteristics that control regional-scale response to climate change. The overall near-term outlook for agricultural production in the CRB is largely positive, with yield increases for most crops and small overall increases in irrigation demand. However, there are crop-specific and location-specific negative impacts as well, and the aggregate regional response of irrigation demands to climate change is highly sensitive to the spatial crop mix. Low-value pasture/hay varieties of crops—typically not considered in climate change assessments—play a significant role in determining the regional response of irrigation demands to climate change, and thus cannot be overlooked. While, the overall near-term outlook for agriculture in the region is largely positive, there may be potential for a negative outlook further into the future, and it is important to consider this in long-term planning.
Simulated Near-term Climate Change Impacts on Major Crops across Latin America and the Caribbean
NASA Astrophysics Data System (ADS)
Gourdji, S.; Mesa-Diez, J.; Obando-Bonilla, D.; Navarro-Racines, C.; Moreno, P.; Fisher, M.; Prager, S.; Ramirez-Villegas, J.
2016-12-01
Robust estimates of climate change impacts on agricultural production can help to direct investments in adaptation in the coming decades. In this study commissioned by the Inter-American Development Bank, near-term climate change impacts (2020-2049) are simulated relative to a historical baseline period (1971-2000) for five major crops (maize, rice, wheat, soybean and dry bean) across Latin America and the Caribbean (LAC) using the DSSAT crop model. No adaptation or technological change is assumed, thereby providing an analysis of existing climatic stresses on yields in the region and a worst-case scenario in the coming decades. DSSAT is run across irrigated and rain-fed growing areas in the region at a 0.5° spatial resolution for each crop. Crop model inputs for soils, planting dates, crop varieties and fertilizer applications are taken from previously-published datasets, and also optimized for this study. Results show that maize and dry bean are the crops most affected by climate change, followed by wheat, with only minimal changes for rice and soybean. Generally, rain-fed production sees more severe yield declines than irrigated production, although large increases in irrigation water are needed to maintain yields, reducing the yield-irrigation productivity in most areas and potentially exacerbating existing supply limitations in watersheds. This is especially true for rice and soybean, the two crops showing the most neutral yield changes. Rain-fed yields for maize and bean are projected to decline most severely in the sub-tropical Caribbean, Central America and northern South America, where climate models show a consistent drying trend. Crop failures are also projected to increase in these areas, necessitating switches to other crops or investment in adaptation measures. Generally, investment in agricultural adaptation to climate change (such as improved seed and irrigation infrastructure) will be needed throughout the LAC region in the 21st century.
New soil water sensors for irrigation management
USDA-ARS?s Scientific Manuscript database
Effective irrigation management is key to obtaining the most crop production per unit of water applied and increasing production in the face of competing demands on water resources. Management methods have included calculating crop water needs based on weather station measurements, calculating soil ...
Modelling the influence of irrigation on the shrinking Aral Sea
NASA Astrophysics Data System (ADS)
Aus der Beek, Tim; Voss, Frank; Floerke, Martina
2010-05-01
The Aral Sea is fed by two tributaries, the Amu Darya and the Syr Darya, and often is considered as one of the most complex hydrological basins of the world. The shrinkage of the Aral Sea during the last 50 years, which has been caused by excessive irrigation projects, has led to numerous ecological, human and economical problems. This study focuses on historic modelling (1960-2002) of the Amu Darya (535,000 km²) and the Syr Darya (219,000 km²) to assess the influence of land-use change, i.e. conversion of non-cultivated land to irrigated crops, on the hydrological cycle and on the shrinkage of the Aral Sea. Therefore, we have compiled crop- and irrigation-specific land use maps in five year intervals from extensive literature and data base reviews. These maps are first applied within the WaterGAP irrigation model, which has been further developed to account for the seven major crops of Central Asia, to compute crop-specific net irrigation requirements. In combination with a newly set up data base on time series of irrigation project efficiencies for Iran, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan we have also been able to depict crop-specific gross irrigation requirements. These results have then been applied within the WaterGAP hydrology model, where they alter the water balance of each affected grid cell, and thus, runoff generation. All irrigation and hydrology calculations have been conducted in daily time steps and five arc minutes spatial resolution (~ 8 x 10 km grid cells) for the entire Aral Sea basin. Climate forcing data for the 42 year period has been taken from the CRU TS2.1 data set. First results of this model experiment show that not only massive water abstractions have caused the changes in the hydrological regime of both rivers, but also poor land and water management has taken its toll. Between 1960 and 1990 a state driven land use conversion from locally adapted food crops, such as cereals, to water intensive cash crops, such as cotton, has taken place. This and other factors have led to nearly doubling of water withdrawals within the basin. One further example is the on-going construction of the Karakum Canal, which diverts about 18km³ per year from the Amu Darya to the Karakum Desert, causing immense changes in the hydrograph and inflow to the Aral Sea. Due to poor water management, i.e. transmission losses of up to ~12km³ per year and old irrigation systems, most of the diverted canal water cannot be used for irrigation purposes. The influence of climate change in the Aral Sea basin between 1960 and 2002 is evident. However, excessive water abstractions mask climate change induced hydrological regime changes.
Optimization of Water Resources and Agricultural Activities for Economic Benefit in Colorado
NASA Astrophysics Data System (ADS)
LIM, J.; Lall, U.
2017-12-01
The limited water resources available for irrigation are a key constraint for the important agricultural sector of Colorado's economy. As climate change and groundwater depletion reshape these resources, it is essential to understand the economic potential of water resources under different agricultural production practices. This study uses a linear programming optimization at the county spatial scale and annual temporal scales to study the optimal allocation of water withdrawal and crop choices. The model, AWASH, reflects streamflow constraints between different extraction points, six field crops, and a distinct irrigation decision for maize and wheat. The optimized decision variables, under different environmental, social, economic, and physical constraints, provide long-term solutions for ground and surface water distribution and for land use decisions so that the state can generate the maximum net revenue. Colorado, one of the largest agricultural producers, is tested as a case study and the sensitivity on water price and on climate variability is explored.
A Computer Program for Drip Irrigation System Design for Small Plots
NASA Astrophysics Data System (ADS)
Philipova, Nina; Nicheva, Olga; Kazandjiev, Valentin; Chilikova-Lubomirova, Mila
2012-12-01
A computer programhas been developed for design of surface drip irrigation system. It could be applied for calculation of small scale fields with an area up to 10 ha. The program includes two main parts: crop water requirements and hydraulic calculations of the system. It has been developed in Graphical User Interface in MATLAB and gives opportunity for selecting some parameters from tables such as: agro- physical soil properties, characteristics of the corresponding crop, climatic data. It allows the user of the program to assume and set a definite value, for example the emitter discharge, plot parameters and etc. Eight cases of system layout according to the water source layout and the number of plots of the system operation are laid into hydraulic section of the program. It includes the design of lateral, manifold, main line and pump calculations. The program has been compiled to work in Windows.
NASA Astrophysics Data System (ADS)
Garcia-Vila, Margarita; Gamero-Ojeda, Pablo; Ascension Carmona, Maria; Berlanga, Jose; Fereres, Elias
2017-04-01
Dissemination of sustainable irrigation strategies for almond and olive orchards via a participatory approach. Project LIFE+IRRIMAN Spain is the world's first and third largest producer of olive oil and almond, respectively. Despite huge efforts in the last years by the production sector towards intensification, cultural issues relative to the traditional rain-fed crop management know how, prevent farmers from adoption of sustainable irrigation management practices. Consequently, even though there has been progress in irrigation management research for these two crops, adoption of modern irrigation techniques by farmers has been slow. Sustainable irrigation strategies for olive and almond orchards are being designed, implemented, validated and disseminated under the framework of the LIFE+ IRRIMAN project, through a participatory approach. The implementation of the LIFE+ IRRIMAN innovative and demonstrative actions has been carried out in an irrigation district of Southern Spain (Genil-Cabra Irrigation Scheme, Andalusia). The approach designed has four phases: i) design and implementation of sustainable irrigation strategies in demonstration farms; ii) dissemination of best irrigation practices which were tested in the initial year throughout the irrigation scheme by the irrigation advisory service; iii) assessment of degree of adoption and re-design of the dissemination strategies; and, iv) based on the results obtained, elaboration of sustainable irrigation guidelines for knowledge transfer in the district at regional and national levels to promote changes in irrigation practices. Participatory approaches have proven to be effective tools for successful irrigation strategies design and diffusion, especially in traditional rain fed crops such as olive and almond trees in the Mediterranean countries. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).
Climate Change Implications to Irrigated Rice Production in Southern Brazil: A Modelling Approach
NASA Astrophysics Data System (ADS)
Dos Santos, Thiago
Rice is one of the staple foods for more than three billion people worldwide. When cultivated under irrigated conditions (i.e. lowland rice), rice is one of the most intensive water consumer crops globally. Therefore, representation of rice growth should be integrated into the latest land surface models to allow studies on food security and to ensure that accurate simulations of the bidirectional feedbacks between the land surface and atmosphere take place. In this study, I present a new process-based model for rice fields that includes rice growth and rice irrigation as modules within the Agro-IBIS dynamic agro-ecosystem model. The model includes a series of equations, agricultural management parameters and an irrigation scheme that are specifically tailored for rice crops. The model was evaluated against leaf area index and biomass observations, obtained for one growing season in Rio Grande do Sul state (southern Brazil), and in Los Banos, Philippines. The model accurately captured the temporal dynamics of leaf area index in both the Brazilian and the Philippine sites, and predicted end-of-season biomass with an error of between -9.5% and 11.3% depending on the location and the plant organ. Rice phenology is predicted by the model based on experimentally-derived growth rates, and was evaluated by comparing simulated and observed durations of the four growth phases considered by the model. Agro-IBIS showed a tendency to overestimate the duration of the growth stages between 3% and 16%, but underestimated by 8% the duration of the panicle formation phase in one growing season. The new irrigation model is based on the water balance at the surface and applies irrigation in order to keep the water layer at the paddy field always in the optimum level. A set of climate projections from global climate models under two emission scenarios, and excluding and considering CO2 fertilizations effects, was used to drive the updated Agro-IBIS to estimate the effects of climate change on rice phenology, productivity and irrigation demand in southern Brazil during the 21st century. The results suggest that rice yields in southern Brazil can increase in average by 10-30%, but by up to 80% in regions where the current temperature is below optimum for rice growth and therefore will be benefited by warming. However, the same region might experience higher water demand for rice irrigation, which might pose a challenge for rice production in that region.
Dynamic Predictions of Crop Yield and Irrigation in Sub-Saharan Africa Due to Climate Change Impacts
NASA Astrophysics Data System (ADS)
Foster-Wittig, T.
2012-12-01
The highest damages from climate change are predicted to be in the agricultural sector in sub-Saharan Africa. Agriculture is predicted to be especially vulnerable in this region because of its current state of high temperature and low precipitation and because it is usually rain-fed or relies on relatively basic technologies which therefore limit its ability to sustain in increased poor climatic conditions [1]. The goal of this research is to quantify the vulnerability of this ecosystem by projecting future changes in agriculture due to IPCC predicted climate change impacts on precipitation and temperature. This research will provide a better understanding of the relationship between precipitation and rain-fed agriculture in savannas. In order to quantify the effects of climate change on agriculture, the impacts of climate change are modeled through the use of a land surface vegetation dynamics model previously developed combined with a crop model [2,4]. In this project, it will be used to model yield for point cropland locations within sub-Saharan Africa between Kenya and Botswana with a range of annual rainfall. With this model, future projections are developed for what can be anticipated for the crop yield based on two precipitation climate change scenarios; (1) decreased depth and (2) decreased frequency as well as temperature change scenarios; (3) only temperature increased, (4) temperature increase dand decreased precipitation depth, and (5) temperature increased and decreased precipitation frequency. Therefore, this will allow conclusions to be drawn about how mean precipitation and a changing climate effect food security in sub-Saharan Africa. As an additional analysis, irrigation is added to the model as it is thought to be the solution to protect food security by maximizing on the potential of food production. In water-limited areas such as Sub-Saharan Africa, it is important to consider water efficient irrigation techniques such as demand-based micro-irrigation where less water is lost to evaporative demand. Demand-based irrigation is based on two main parameters; a trigger level, to initiate the irrigation, and a target level to calculate the amount of irrigation [3]. In order to understand the impact of these two parameters on amount of irrigated water and yield, irrigation is added to the model with variations of these two parameters considered. This analysis will provide the information needed to understand whether irrigation is a feasible and sustainable solution to the loss of food production due to climate change. Resources: [1]Kurukulasuriya, P., and Mendelsohn, Robert (2008). "A Ricardian analysis of the impact of climate change on African cropland." African Journal Agriculture and Resource Economics 02(1). [2]Raes, D., Steduto, P., Hsiao, T., and Fereres, E. (2011). Chapter 3: Calculation Procedure. . AquaCrop Reference Manual Version 3.1 Plus. [3]Vico, G. and A. Porporato (2011). "From rainfed agriculture to stress-avoidance irrigation: I. A generalized irrigation scheme with stochastic soil moisture." Advances in Water Resources 34(2): 263-271. [4]Williams, C., and Albertson, J. (2005). "Contrasting Short- and Long-Timescale Effects of Vegetation Dynamics on Water and Carbon Fluxes in Water-Limited Ecosystems." Water Resources Research. 41: 1-13
NASA Astrophysics Data System (ADS)
Gupta, M.; Bolten, J. D.; Lakshmi, V.
2016-12-01
Water scarcity is one of the main factors limiting agricultural development. Numerical models integrated with remote sensing datasets are increasingly being used operationally as inputs for crop water balance models and agricultural forecasting due to increasing availability of high temporal and spatial resolution datasets. However, the model accuracy in simulating soil water content is affected by the accuracy of the soil hydraulic parameters used in the model, which are used in the governing equations. However, soil databases are known to have a high uncertainty across scales. Also, for agricultural sites, the in-situ measurements of soil moisture are currently limited to discrete measurements at specific locations, and such point-based measurements do not represent the spatial distribution at a larger scale accurately, as soil moisture is highly variable both spatially and temporally. The present study utilizes effective soil hydraulic parameters obtained using a 1-km downscaled microwave remote sensing soil moisture product based on the NASA Advanced Microwave Scanning Radiometer (AMSR-E) using the genetic algorithm inverse method within the Catchment Land Surface Model (CLSM). Secondly, to provide realistic irrigation estimates for agricultural sites, an irrigation scheme within the land surface model is triggered when the root-zone soil moisture deficit reaches the threshold, 50% with respect to the maximum available water capacity obtained from the effective soil hydraulic parameters. An additional important criterion utilized is the estimation of crop water consumption based on dynamic root growth and uptake in root zone layer. Model performance is evaluated using MODIS land surface temperature (LST) product. The soil moisture estimates for the root zone are also validated with the in situ field data, for three sites (2- irrigated and 1- rainfed) located at the University of Nebraska Agricultural Research and Development Center near Mead, NE and monitored by three AmeriFlux installations (Verma et al., 2005).
Liu, Jing; Sun, Shikun; Wu, Pute; Wang, Yubao; Zhao, Xining
2015-02-01
The integration of water footprints and virtual water flows allows the mapping of the links between production, trade, and consumption and could potentially help to alleviate water scarcity and improve water management. We evaluated the water footprints and virtual water flows of crop production, consumption, and trade and their influencing factors in the Hetao irrigation district in China for 1960-2010. The water footprint of crop production and the export of virtual water fluctuated but tended to increase during this period and were influenced mainly by agricultural factors such as crop yield, irrigation efficiency, and area sown. The water footprint of crop consumption and the import of virtual water increased during 1960-1979 and decreased during 1980-2010 and were influenced by socio-economic factors such as total population, the retail-price index, and the proportion of the population in urban areas. Most of the water footprint of production was exported to other areas, which added to the pressure on local water systems. The import of virtual water led to a saving of water for the Hetao irrigation district, while its share of the water footprint of consumption has decreased significantly since 1977. An increase in irrigation efficiency can alleviate water scarcity, and its application should be coupled with measures that constrain the continued expansion of agriculture. Full-cost pricing of irrigation water was an effective policy tool for its management. Re-shaping regional water-production and water-trade nexuses by changing crop structures could provide alternative opportunities for addressing the problems of local water scarcity, but the trade-offs involved should first be assessed. Copyright © 2014 Elsevier B.V. All rights reserved.
Heavy Metal Contamination of Vegetables Irrigated by Urban Stormwater: A Matter of Time?
Tom, Minna; Fletcher, Tim D.; McCarthy, David T.
2014-01-01
Urban stormwater is a crucial resource at a time when climate change and population growth threaten freshwater supplies; but there are health risks from contaminants, such as toxic metals. It is vitally important to understand how to use this resource safely and responsibly. Our study investigated the extent of metal contamination in vegetable crops irrigated with stormwater under short- and long-term conditions. We created artificially aged gardens by adding metal-contaminated sediment to soil, simulating accumulation of metals in the soil from irrigation with raw stormwater over zero, five and ten years. Our crops - French bean (Phaseolus vulgaris), kale (Brassica oleracea var. acephala), and beetroot (Beta vulgaris) - were irrigated twice a week for 11 weeks, with either synthetic stormwater or potable water. They were then tested for concentrations of Cd, Cr, Pb, Cu and Zn. An accumulation of Pb was the most marked sign of contamination, with six of nine French bean and seven of nine beetroot leaf samples breaching Australia's existing guidelines. Metal concentration in a crop tended to increase with the effective age of the garden; but importantly, its rate of increase did not match the rate of increase in the soil. Our study also highlighted differences in sensitivity between different crop types. French bean demonstrated the highest levels of uptake, while kale displayed restrictive behaviour. Our study makes it clear: irrigation with stormwater is indeed feasible, as long as appropriate crops are selected and media are frequently turned over. We have also shown that an understanding of such risks yields meaningful information on appropriate safeguards. A holistic approach is needed - to account for all routes to toxic metal exposure, including especially Pb. A major outcome of our study is critical information for minimising health risks from stormwater irrigation of crops. PMID:25426946
Heavy metal contamination of vegetables irrigated by urban stormwater: a matter of time?
Tom, Minna; Fletcher, Tim D; McCarthy, David T
2014-01-01
Urban stormwater is a crucial resource at a time when climate change and population growth threaten freshwater supplies; but there are health risks from contaminants, such as toxic metals. It is vitally important to understand how to use this resource safely and responsibly. Our study investigated the extent of metal contamination in vegetable crops irrigated with stormwater under short- and long-term conditions. We created artificially aged gardens by adding metal-contaminated sediment to soil, simulating accumulation of metals in the soil from irrigation with raw stormwater over zero, five and ten years. Our crops--French bean (Phaseolus vulgaris), kale (Brassica oleracea var. acephala), and beetroot (Beta vulgaris)--were irrigated twice a week for 11 weeks, with either synthetic stormwater or potable water. They were then tested for concentrations of Cd, Cr, Pb, Cu and Zn. An accumulation of Pb was the most marked sign of contamination, with six of nine French bean and seven of nine beetroot leaf samples breaching Australia's existing guidelines. Metal concentration in a crop tended to increase with the effective age of the garden; but importantly, its rate of increase did not match the rate of increase in the soil. Our study also highlighted differences in sensitivity between different crop types. French bean demonstrated the highest levels of uptake, while kale displayed restrictive behaviour. Our study makes it clear: irrigation with stormwater is indeed feasible, as long as appropriate crops are selected and media are frequently turned over. We have also shown that an understanding of such risks yields meaningful information on appropriate safeguards. A holistic approach is needed--to account for all routes to toxic metal exposure, including especially Pb. A major outcome of our study is critical information for minimising health risks from stormwater irrigation of crops.
Zhang, Ming Zhi; Niu, Wen Quan; Xu, Jian; Li, Yuan
2016-06-01
In order to explore the influences of micro-irrigation and subsoiling before planting on enzyme activity in soil rhizosphere and summer maize yield, an orthogonal experiment was carried out with three factors of micro-irrigation method, irrigation depth, and subsoiling depth. The factor of irrigation method included surface drip irrigation, subsurface drip irrigation, and moistube-irrigation; three levels of irrigation depth were obtained by controlling the lower limit of soil water content to 50%, 65%, and 80% of field holding capacity, respectively; and three depths of deep subsoiling were 20, 40, and 60 cm. The results showed that the activities of catalase and urease increased first and then decreased, while the activity of phosphatase followed an opposite trend in the growth season of summer maize. Compared with surface drip irrigation and moistube-irrigation, subsurface drip irrigation increased the average soil moisture of 0-80 cm layer by 6.3% and 1.8% in the growth season, respectively. Subsurface drip irrigation could significantly increase soil urease activity, roots volume, and yield of summer maize. With the increase of irrigation level, soil phosphatase activity decreased first and then increased, while urease activity and yield increased first and then decreased. The average soil moisture and root volume all increased in the growth season of summer maize. The increments of yield and root volume from subsoiling of 40 to 20 cm were greater than those from 60 to 40 cm. The highest enzyme activity was obtained with the treatment of subsoiling of 40 cm. In terms of improving water resource use efficiency, nitrogen use efficiency, and crop yield, the best management strategy of summer maize was the combination of subsurface drip irrigation, controlling the lower limit of soil water content to 65% of field holding capacity, and 40 cm subsoiling before planting.
Transfer of antibiotics from wastewater or animal manure to soil and edible crops.
Pan, Min; Chu, L M
2017-12-01
Antibiotics are added to agricultural fields worldwide through wastewater irrigation or manure application, resulting in antibiotic contamination and elevated environmental risks to terrestrial environments and humans. Most studies focused on antibiotic detection in different matrices or were conducted in a hydroponic environment. Little is known about the transfer of antibiotics from antibiotic-contaminated irrigation wastewater and animal manure to agricultural soil and edible crops. In this study, we evaluated the transfer of five different antibiotics (tetracycline, sulfamethazine, norfloxacin, erythromycin, and chloramphenicol) to different crops under two levels of antibiotic-contaminated wastewater irrigation and animal manure fertilization. The final distribution of tetracycline (TC), norfloxacin (NOR) and chloramphenicol (CAP) in the crop tissues under these four treatments were as follows: fruit > leaf/shoot > root, while an opposite order was found for sulfamethazine (SMZ) and erythromycin (ERY): root > leaf/shoot > fruit. The growth of crops could accelerate the dissipation of antibiotics by absorption from contaminated soil. A higher accumulation of antibiotics was observed in crop tissues under the wastewater treatment than under manure treatment, which was due to the continual irrigation that increased adsorption in soil and uptake by crops. The translocation of antibiotics in crops mainly depended on their physicochemical properties (e.g. log K ow ), crop species, and the concentrations of antibiotics applied to the soil. The levels of antibiotics ingested through the consumption of edible crops under the different treatments were much lower than the acceptable daily intake (ADI) levels. Copyright © 2017 Elsevier Ltd. All rights reserved.
Monitoring crop coefficient of orange orchards using energy balance and the remote sensed NDVI
NASA Astrophysics Data System (ADS)
Consoli, Simona; Cirelli, Giuseppe Luigi; Toscano, Attilio
2006-09-01
The structure of vegetation is paramount in regulating the exchange of mass and energy across the biosphereatmosphere interface. In particular, changes in vegetation density affected the partitioning of incoming solar energy into sensible and latent heat fluxes that may result in persistent drought through reductions in agricultural productivity and in the water resources availability. Limited research with citrus orchards has shown improvements to irrigation scheduling due to better water-use estimation and more appropriate timing of irrigation when crop coefficient (Kc) estimate, derived from remotely sensed multispectral vegetation indices (VIs), are incorporated into irrigation-scheduling algorithms. The purpose of this article is the application of an empirical reflectance-based model for the estimation of Kc and evapotranspiration fluxes (ET) using ground observations on climatic data and high-resolution VIs from ASTER TERRA satellite imagery. The remote sensed Kc data were used in developing the relationship with the normalized difference vegetation index (NDVI) for orange orchards during summer periods. Validation of remote sensed data on ET, Kc and vegetation features was deal through ground data observations and the resolution of the energy balance to derive latent heat flux density (λE), using measures of net radiation (Rn) and soil heat flux density (G) and estimate of sensible heat flux density (H) from high frequency temperature measurements (Surface Renewal technique). The chosen case study is that of an irrigation area covered by orange orchards located in Eastern Sicily, Italy) during the irrigation seasons 2005 and 2006.
NASA Astrophysics Data System (ADS)
Yang, B.; Lee, D. K.
2016-12-01
Understanding spatial distribution of irrigation requirement is critically important for agricultural water management. However, many studies considering future agricultural water management in Korea assessed irrigation requirement on watershed or administrative district scale, but have not accounted the spatial distribution. Lumped hydrologic model has typically used in Korea for simulating watershed scale irrigation requirement, while distribution hydrologic model can simulate the spatial distribution grid by grid. To overcome this shortcoming, here we applied a grid base global hydrologic model (H08) into local scale to estimate spatial distribution under future irrigation requirement of Korean Peninsula. Korea is one of the world's most densely populated countries, with also high produce and demand of rice which requires higher soil moisture than other crops. Although, most of the precipitation concentrate in particular season and disagree with crop growth season. This precipitation character makes management of agricultural water which is approximately 60% of total water usage critical issue in Korea. Furthermore, under future climate change, the precipitation predicted to be more concentrated and necessary need change of future water management plan. In order to apply global hydrological model into local scale, we selected appropriate major crops under social and local climate condition in Korea to estimate cropping area and yield, and revised the cropping area map more accurately. As a result, future irrigation requirement estimation varies under each projection, however, slightly decreased in most case. The simulation reveals, evapotranspiration increase slightly while effective precipitation also increase to balance the irrigation requirement. This finding suggest practical guideline to decision makers for further agricultural water management plan including future development of water supply plan to resolve water scarcity.
NASA Astrophysics Data System (ADS)
Pelosi, Anna; Falanga Bolognesi, Salvatore; De Michele, Carlo; Medina Gonzalez, Hanoi; Villani, Paolo; D'Urso, Guido; Battista Chirico, Giovanni
2015-04-01
Irrigation agriculture is one the biggest consumer of water in Europe, especially in southern regions, where it accounts for up to 70% of the total water consumption. The EU Common Agricultural Policy, combined with the Water Framework Directive, imposes to farmers and irrigation managers a substantial increase of the efficiency in the use of water in agriculture for the next decade. Ensemble numerical weather predictions can be valuable data for developing operational advisory irrigation services. We propose a stochastic ensemble-based model providing spatial and temporal estimates of crop water requirements, implemented within an advisory service offering detailed maps of irrigation water requirements and crop water consumption estimates, to be used by water irrigation managers and farmers. The stochastic model combines estimates of crop potential evapotranspiration retrieved from ensemble numerical weather forecasts (COSMO-LEPS, 16 members, 7 km resolution) and canopy parameters (LAI, albedo, fractional vegetation cover) derived from high resolution satellite images in the visible and near infrared wavelengths. The service provides users with daily estimates of crop water requirements for lead times up to five days. The temporal evolution of the crop potential evapotranspiration is simulated with autoregressive models. An ensemble Kalman filter is employed for updating model states by assimilating both ground based meteorological variables (where available) and numerical weather forecasts. The model has been applied in Campania region (Southern Italy), where a satellite assisted irrigation advisory service has been operating since 2006. This work presents the results of the system performance for one year of experimental service. The results suggest that the proposed model can be an effective support for a sustainable use and management of irrigation water, under conditions of water scarcity and drought. Since the evapotranspiration term represents a staple component in the water balance of a catchment, as outstanding future development, the model could also offer an advanced support for water resources management decisions at catchment scale.
Gong, Xue Wen; Liu, Hao; Sun, Jing Sheng; Ma, Xiao Jian; Wang, Wan Ning; Cui, Yong Sheng
2017-04-18
An experiment was conducted to investigate soil evaporation (E), crop transpiration (T), evapotranspiration (ET) and the ratio of evaporation to evapotranspiration (E/ET) of drip-irrigated tomato, which was planted in a typical solar greenhouse in the North China, under different water conditions [irrigation amount was determined based on accumulated pan evaporation (E p ) of 20 cm pan evaporation, and two treatments were designed with full irrigation (0.9E p ) and deficit irrigation (0.5E p )] at different growth stages in 2015 and 2016 at Xinxiang Comprehensive Experimental Station, Chinese Academy of Agricultural Sciences. Effects of deficit irrigation on crop coefficient (K c ) and variation of water stress coefficient (K s ) throughout the growing season were also discussed. E, T and ET of tomato were calculated with a dual crop coefficient approach, and compared with the measured data. Results indicated that E in the full irrigation was 21.5% and 20.4% higher than that in the deficit irrigation in 2015 and 2016, respectively, accounting for 24.0% and 25.0% of ET in the whole growing season. The maximum E/ET was measured in the initial stage of tomato, while the minimum obtained in the middle stage. The K c the full irrigation was 0.45, 0.89, 1.06 and 0.93 in the initial, development, middle, and late stage of tomato, and 0.45, 0.89, 0.87 and 0.41 the deficit irrigation. The K s the deficit irrigation was 0.98, 0.93, 0.78 and 0.39 in the initial, development, middle, and late stage, respectively. The dual crop coefficient method could accurately estimate ET of greenhouse tomato under different water conditions in 2015 and 2016 seasons with the mean absolute error (MAE) of 0.36-0.48 mm·d -1 , root mean square error (RMSE) of 0.44-0.65 mm·d -1 . The method also estimated E and T accurately with MAE of 0.15-0.19 and 0.26-0.56 mm·d -1 , and with RMSE of 0.20-0.24 and 0.33-0.72 mm·d -1 , respectively.
NASA Astrophysics Data System (ADS)
Chen, Chao; Baethgen, Walter E.; Wang, Enli; Yu, Qiang
2011-12-01
Grain yields of wheat and maize were obtained from national statistics and simulated with an agricultural system model to investigate the effects of historical climate variability and irrigation on crop yield in the North China Plain (NCP). Both observed and simulated yields showed large temporal and spatial variability due to variations in climate and irrigation supply. Wheat yield under full irrigation (FI) was 8 t ha-1 or higher in 80% of seasons in the north, it ranged from 7 to 10 t ha-1 in 90% of seasons in central NCP, and less than 9 t ha-1 in 85% of seasons in the south. Reduced irrigation resulted in increased crop yield variability. Wheat yield under supplemental irrigation, i.e., to meet only 50% of irrigation water requirement [supplemental irrigation (SI)] ranged from 2.7 to 8.8 t ha-1 with the maximum frequency of seasons having the range of 4-6 t ha-1 in the north, 4-7 t ha-1 in central NCP, and 5-8 t ha-1 in the south. Wheat yield under no irrigation (NI) was lower than 1 t ha-1 in about 50% of seasons. Considering the NCP as a whole, simulated maize yield under FI ranged from 3.9 to 11.8 t ha-1 with similar frequency distribution in the range of 6-11.8 t ha-1 with the interval of 2 t ha-1. It ranged from 0 to 11.8 t ha-1, uniformly distributed into the range of 4-10 t ha-1 under SI, and NI. The results give an insight into the levels of regional crop production affected by climate and water management strategies.
A UAS-based remote sensing platform for crop water stress detection
NASA Astrophysics Data System (ADS)
Zhang, H.; Wang, D.; Ayars, J. E.
2014-12-01
The remote detection of water stress in a biofuel crop field was investigated using canopy temperature measurements. An experimental trial was set up in the central valley of Maui, Hawaii, comprising different sugarcane varieties and irrigation regimes. An unmanned aerial system (UAS) was equipped with a FLIR A615 thermal camera to acquire canopy temperature imagery. Images were mosaicked and processed to show spatial temperature difference of entire field. A weather station was installed in a full irrigation plot to collect meteorological parameters. The sensitivity of canopy to air temperature difference and crop water stress index were investigated on detecting cop water stress levels. The results showed that low irrigation level treatment plots resulted in higher canopy temperatures compared to the high irrigation level treatment plots. Canopy temperatures also showed differences in water stress in different sugarcane varieties. The study demonstrated the feasibility of UAS-based thermal method to quantify plant water status of sugar canes used for biofuel crops.
Coupled stochastic soil moisture simulation-optimization model of deficit irrigation
NASA Astrophysics Data System (ADS)
Alizadeh, Hosein; Mousavi, S. Jamshid
2013-07-01
This study presents an explicit stochastic optimization-simulation model of short-term deficit irrigation management for large-scale irrigation districts. The model which is a nonlinear nonconvex program with an economic objective function is built on an agrohydrological simulation component. The simulation component integrates (1) an explicit stochastic model of soil moisture dynamics of the crop-root zone considering interaction of stochastic rainfall and irrigation with shallow water table effects, (2) a conceptual root zone salt balance model, and 3) the FAO crop yield model. Particle Swarm Optimization algorithm, linked to the simulation component, solves the resulting nonconvex program with a significantly better computational performance compared to a Monte Carlo-based implicit stochastic optimization model. The model has been tested first by applying it in single-crop irrigation problems through which the effects of the severity of water deficit on the objective function (net benefit), root-zone water balance, and irrigation water needs have been assessed. Then, the model has been applied in Dasht-e-Abbas and Ein-khosh Fakkeh Irrigation Districts (DAID and EFID) of the Karkheh Basin in southwest of Iran. While the maximum net benefit has been obtained for a stress-avoidance (SA) irrigation policy, the highest water profitability has been resulted when only about 60% of the water used in the SA policy is applied. The DAID with respectively 33% of total cultivated area and 37% of total applied water has produced only 14% of the total net benefit due to low-valued crops and adverse soil and shallow water table conditions.
Sustainable Irrigation Allocation Model for Dry and Wet Periods using Reservoir Storage and Inflow
NASA Astrophysics Data System (ADS)
Surianarayanan, S.; Suribabu, C. R.; Ramakrishnan, K.
2017-07-01
The dry period agriculture is inevitable both for the farmers for their earning, and for the soil for its fertility by crop-rotation. In tropical countries like INDIA, dry period agriculture becomes difficult because of less (or) no rain fall. Hence a simple water balancing model for irrigation scheduling, using the measure “Volumetric Reliability” is prepared in this paper, with the storage and inflow of a reservoir both for the dry and wet periods. The case-study is done for a reservoir in INDIA with thirty one years of hydrological data(from 1982 to 2012). The objective of this paper is to prepare a simple water balance model taking 10 days periods of demand and supply for ID crop(Irrigated Dry crop, ground nut) with usage of volumetric reliability concept for the periods of deficiency and adoption of less water requirement crops to reduce the water-stress during critical periods of crop growth, and finally arrive at a feasible allocation schedule for the success of agriculture and the yield throughout the year both for wet and dry crops with the available storage on the start of irrigation for a particular year. The reservoir is divided for storages such as full, deficient and critical storages. The starting storage for the dry period from January is used after adequate allocation for wet crops, the quantity for riparian rights and for drinking water, for the sustainability. By the water-balancing, the time-series for thirty one years, it is found that for twenty two years the demand for the ID crops is satisfied with the storage in the reservoir, and in the remaining years of deficient inflows, for three years (1986,1996,2004)the demand is managed by using the safe reliability factor for demand which can nullify the deficit in demand for the whole supply period. But it is genuine to assure that the reduction in the amount of water for each 10 days periods should not exceed the survival limit of the crop. Necessary soil-moisture must be ensured in the crop in its root zone.. A safe volumetric reliability factor of 0.75 is taken in this attempt to extend the success of dry period agriculture. The soil moisture balance in the clayey loam soil due to continuous irrigation can manage the deficiency, so that the soil-water does not go below the wilting point but must be checked with the soil-moisture sensors. The methods to reduce the evaporation from the soil, such as usage of drip irrigation and the mulching, which can reduce the crop water requirements in comparison with the conventional irrigation which is being followed at present in the spot of the case-study is suggested. In addition to these methods less water requirement crops like flowers, vegetables having less crop-period and provision of windbreak to reduce evapo-transpiration rates and other efficient methods of water management can make success of dry period agriculture even in the years critical storage level in the reservoir. The rainfall is not taken in this model which if in a year with ample quantity can be used for pre-sowing and for managing the water-stress. Augmentation of water with ground water, percolation tank can boost the level of success of agriculture. As the irrigation water allocation for the whole year, particularly for the ID crops is prepared for the full, deficient and critical storages, this paper can help to achieve sustainable growth of crops throughout the year.
Mapping irrigated lands at 250-m scale by merging MODIS data and National Agricultural Statistics
Pervez, Md Shahriar; Brown, Jesslyn F.
2010-01-01
Accurate geospatial information on the extent of irrigated land improves our understanding of agricultural water use, local land surface processes, conservation or depletion of water resources, and components of the hydrologic budget. We have developed a method in a geospatial modeling framework that assimilates irrigation statistics with remotely sensed parameters describing vegetation growth conditions in areas with agricultural land cover to spatially identify irrigated lands at 250-m cell size across the conterminous United States for 2002. The geospatial model result, known as the Moderate Resolution Imaging Spectroradiometer (MODIS) Irrigated Agriculture Dataset (MIrAD-US), identified irrigated lands with reasonable accuracy in California and semiarid Great Plains states with overall accuracies of 92% and 75% and kappa statistics of 0.75 and 0.51, respectively. A quantitative accuracy assessment of MIrAD-US for the eastern region has not yet been conducted, and qualitative assessment shows that model improvements are needed for the humid eastern regions where the distinction in annual peak NDVI between irrigated and non-irrigated crops is minimal and county sizes are relatively small. This modeling approach enables consistent mapping of irrigated lands based upon USDA irrigation statistics and should lead to better understanding of spatial trends in irrigated lands across the conterminous United States. An improved version of the model with revised datasets is planned and will employ 2007 USDA irrigation statistics.
IRRIMET: a web 2.0 advisory service for irrigation water management
NASA Astrophysics Data System (ADS)
De Michele, Carlo; Anzano, Enrico; Colandrea, Marco; Marotta, Luigi; Mula, Ileana; Pelosi, Anna; D'Urso, Guido; Battista Chirico, Giovanni
2016-04-01
Irrigation agriculture is one the biggest consumer of water in Europe, especially in southern regions, where it accounts for up to 70% of the total water consumption. The EU Common Agricultural Policy, combined with the Water Framework Directive, imposes to farmers and irrigation managers a substantial increase of the efficiency in the use of water in agriculture for the next decade. Irrigating according to reliable crop water requirement estimates is one of the most convincing solution to decrease agricultural water use. Here we present an innovative irrigation advisory service, applied in Campania region (Southern Italy), where a satellite assisted irrigation advisory service has been operating since 2006. The advisory service is based on the optimal combination of VIS-NIR high resolution satellite images (Landsat, Deimos, Rapideye) to map crop vigour, and high resolution numerical weather prediction for assessing the meteorological variables driving the crop water needs in the short-medium range. The advisory service is broadcasted with a simple and intuitive web app interface which makes daily real time irrigation and evapotranspiration maps and customized weather forecasts (based on Cosmo Leps model) accessible from desktop computers, tablets and smartphones.
Cotton irrigation timing with variable seasonal irrigation capacities in the Texas south plains.
USDA-ARS?s Scientific Manuscript database
Within the Ogallala Aquifer Region of Texas, the irrigation capacity (IC) for a given field often changes within a growing season due to seasonal depletion of the aquifer, in season changes in crop irrigation needs in dry years, or consequences of irrigation volume limits imposed by irrigation distr...
Sustainability of agricultural water use worldwide
NASA Astrophysics Data System (ADS)
Tuninetti, M.; Tamea, S.; Dalin, C.
2017-12-01
Water is a renewable but limited resource. Most human use of freshwater resources is for agriculture, and global water demand for agriculture is increasing because of the growth in food demand, driven by increasing population and changing diets. Hence, measuring the pressure exerted by agriculture on freshwater sources is a key issue. The sustainability of water use depends on the water source renewability rate: the water use is not sustainable (depleting the water storage) where/when it exceeds the renewable freshwater availability. In this study, we explore the sustainability of rain and irrigation water use for the production of nine major crops, globally at a 5'x5' spatial resolution. We split the crop water use into soil moisture (from rainfall) and irrigation, with, for the first time, separating ground- and surface-water sources, which is a key distinction because the renewability of these two water sources can be very different. In order to physically quantify the extent to which crop water use is sustainable, we measure the severity of the source depletion as the number of years required for the hydrological cycle to replenish the water resource used by the annual crop production, namely the Water Debt. This newly developed indicator allows one to compare the depletion level of the three water sources at a certain location for a specific crop. Hence, we mapped, for each crop, the number of years required to replenish the water withdrawn from soil-, surface- and ground-water resources. Each map identifies the hotspots for each water source, highlighting regions and crops that threaten most the water resource. We found that the water debt with soil moisture is heterogeneous in space but always lower than one year indicating a non-surprising sustainability of rain-fed agriculture. Rice and sugarcane make the largest contribution to global soil moisture depletion. Water debt in surface water is particularly high in areas of intense wheat and cotton production; major hotspots are located along the Nile River and near the Aral Lake. The water debt in groundwater is much larger in the High Plain aquifer and Indo-Gangetic plain. On a global average, seed cotton has the highest WD in surface water (i.e., 6.5 years) while rice has the highest WD in groundwater (i.e., 4.2 years).
Spatial Mapping of Agricultural Water Productivity Using the SWAT Model
NASA Astrophysics Data System (ADS)
Thokal, Rajesh Tulshiram; Gorantiwar, S. D.; Kothari, Mahesh; Bhakar, S. R.; Nandwana, B. P.
2015-03-01
The Sina river basin is facing both episodic and chronic water shortages due to intensive irrigation development. The main objective of this study was to characterize the hydrologic processes of the Sina river basin and assess crop water productivity using the distributed hydrologic model, SWAT. In the simulation year (1998-1999), the inflow to reservoir from upstream side was the major contributor to the reservoir accounting for 92 % of the total required water release for irrigation purpose (119.5 Mm3), while precipitation accounted for 4.1 Mm3. Annual release of water for irrigation was 119.5 Mm3 out of which 54 % water was diverted for irrigation purpose, 26 % was wasted as conveyance loss, average discharge at the command outlet was estimated as 4 % and annual average ground-water recharge coefficient was in the range of 13-17 %. Various scenarios involving water allocation rule were tested with the goal of increasing economic water productivity values in the Sina Irrigation Scheme. Out of those, only most benefited allocation rule is analyzed in this paper. Crop yield varied from 1.98 to 25.9 t/ha, with the majority of the area between 2.14 and 2.78 t/ha. Yield and WP declined significantly in loamy soils of the irrigation command. Crop productivity in the basin was found in the lower range when compared with potential and global values. The findings suggested that there was a potential to improve further. Spatial variations in yield and WP were found to be very high for the crops grown during rabi season, while those were low for the crops grown during kharif season. The crop yields and WP during kharif season were more in the lower reach of the irrigation commands, where loamy soil is more concentrated. Sorghum in both seasons was most profitable. Sorghum fetched net income fivefold that of sunflower, two and half fold of pearl millet and one and half fold of mung beans as far as crop during kharif season were concerned and it fetched fourfold that of groundnut, threefold of wheat, twofold of onion during rabi season and was sevenfold of sugarcane. Analysis suggests that maximization of the area by provision of supplemental irrigation to rainfed areas as well as better on-farm water management practices can provide opportunities for improving water productivity.
Carbon and water footprints of irrigated corn and non-irrigated wheat in Northeast Spain.
Abrahão, Raphael; Carvalho, Monica; Causapé, Jesús
2017-02-01
Irrigation increases yields and allows several crops to be produced in regions where it would be naturally impossible due to limited rainfall. However, irrigation can cause several negative environmental impacts, and it is important to understand these in depth for the correct application of mitigation measures. The life cycle assessment methodology was applied herein to compare the main irrigated and non-irrigated crops in Northeast Spain (corn and wheat, respectively), identifying those processes with greater contribution to environmental impacts (carbon and water footprint categories) and providing scientifically-sound information to facilitate government decisions. Due to concerns about climate change and water availability, the methods selected for evaluation of environmental impacts were IPCC 2013 GWP (carbon footprint) and water scarcity indicator (water footprint). The area studied, a 7.38-km 2 basin, was monitored for 12 years, including the period before, during, and after the implementation of irrigation. The functional unit, to which all material and energy flows were associated with, was the cultivation of 1 ha, throughout 1 year. The overall carbon footprint for irrigated corn was higher, but when considering the higher productivity achieved with irrigation, the emissions per kilogram of corn decrease and finally favor this irrigated crop. When considering the water footprint, the volumes of irrigation water applied were so high that productivity could not compensate for the negative impacts associated with water use in the case of corn. Nevertheless, consideration of productivities and gross incomes brings the results closer. Fertilizer use (carbon footprint) and irrigation water (water footprint) were the main contributors to the negative impacts detected.
Advances in sprinkler irrigation management
USDA-ARS?s Scientific Manuscript database
Sprinkler irrigation is being increasingly adopted in the US and worldwide because it offers increased crop water productivity over what is possible with gravity irrigation. Most sprinkler irrigation is by center pivot, which is presently used on about 50 and 80 percent of land irrigated in the US a...
NASA Technical Reports Server (NTRS)
Bolten, John; Ozdogan, Mutlu; Beaudoing, Hiroko; Rodell, Matthew
2012-01-01
A majority of the countries in the Middle East and North Africa (MENA) region suffer from water scarcity due in part to widespread rainfall deficits, unprecedented levels of water demand, and the inefficient use of renewable freshwater resources. Since a majority of the water withdrawal in the MENA is used for irrigation, there is a desperate need for improved understanding of irrigation practices and agricultural water use in the region. Here, satellite-derived irrigation maps and crop-type agricultural data are applied to the Land Data Assimilation System for the MENA region (MENA LDAS), designed to provide regional, gridded fields of hydrological states and fluxes relevant for water resources assessments. Within MENA-LDAS, the Catchment Land Surface Model (CLSM) simulates the location, timing, and amount of water applied through agricultural irrigation practices over the region from 2002-2012. In addition to simulating the irrigation impact on evapotranspiration, soil moisture, and runoff, we also investigate regional changes in terrestrial water storage (TWS) observed from the Gravity Recovery and Climate Experiment (GRACE) and simulated by CLSM.
NASA Astrophysics Data System (ADS)
Bolten, J. D.; Ozdogan, M.; Beaudoing, H. K.; Rodell, M.
2012-12-01
A majority of the countries in the Middle East and North Africa (MENA) region suffer from water scarcity due in part to widespread rainfall deficits, unprecedented levels of water demand, and the inefficient use of renewable freshwater resources. Since a majority of the water withdrawal in the MENA is used for irrigation, there is a desperate need for improved understanding of irrigation practices and agricultural water use in the region. Here, satellite-derived irrigation maps and crop-type agricultural data are applied to the Land Data Assimilation System for the MENA region (MENA LDAS), designed to provide regional, gridded fields of hydrological states and fluxes relevant for water resources assessments. Within MENA-LDAS, the Catchment Land Surface Model (CLSM) simulates the location, timing, and amount of water applied through agricultural irrigation practices over the region from 2002-2012. In addition to simulating the irrigation impact on evapotranspiration, soil moisture, and runoff, we also investigate regional changes in terrestrial water storage (TWS) observed from the Gravity Recovery and Climate Experiment (GRACE) and simulated by CLSM.
NASA Astrophysics Data System (ADS)
Han, Bangshuai; Benner, Shawn G.; Bolte, John P.; Vache, Kellie B.; Flores, Alejandro N.
2017-07-01
Humans have significantly altered the redistribution of water in intensively managed hydrologic systems, shifting the spatiotemporal patterns of surface water. Evaluating water availability requires integration of hydrologic processes and associated human influences. In this study, we summarize the development and evaluation of an extensible hydrologic model that explicitly integrates water rights to spatially distribute irrigation waters in a semi-arid agricultural region in the western US, using the Envision integrated modeling platform. The model captures both human and biophysical systems, particularly the diversion of water from the Boise River, which is the main water source that supports irrigated agriculture in this region. In agricultural areas, water demand is estimated as a function of crop type and local environmental conditions. Surface water to meet crop demand is diverted from the stream reaches, constrained by the amount of water available in the stream, the water-rights-appropriated amount, and the priority dates associated with particular places of use. Results, measured by flow rates at gaged stream and canal locations within the study area, suggest that the impacts of irrigation activities on the magnitude and timing of flows through this intensively managed system are well captured. The multi-year averaged diverted water from the Boise River matches observations well, reflecting the appropriation of water according to the water rights database. Because of the spatially explicit implementation of surface water diversion, the model can help diagnose places and times where water resources are likely insufficient to meet agricultural water demands, and inform future water management decisions.
Essaid, Hedeff I; Caldwell, Rodney R
2017-12-01
Changes in groundwater discharge to streams caused by irrigation practices can influence stream temperature. Observations along two currently flood-irrigated reaches in the 640-square-kilometer upper Smith River watershed, an important agricultural and recreational fishing area in west-central Montana, showed a downstream temperature decrease resulting from groundwater discharge to the stream. A watershed-scale coupled surface water and groundwater flow model was used to examine changes in streamflow, groundwater discharge to the stream and stream temperature resulting from irrigation practices. The upper Smith River watershed was used to develop the model framework including watershed climate, topography, hydrography, vegetation, soil properties and current irrigation practices. Model results were used to compare watershed streamflow, groundwater recharge, and groundwater discharge to the stream for three scenarios: natural, pre-irrigation conditions (PreIrr); current irrigation practices involving mainly stream diversion for flood and sprinkler irrigation (IrrCurrent); and a hypothetical scenario with only groundwater supplying sprinkler irrigation (IrrGW). Irrigation increased groundwater recharge relative to natural PreIrr conditions because not all applied water was removed by crop evapotranspiration. Groundwater storage and groundwater discharge to the stream increased relative to natural PreIrr conditions when the source of irrigation water was mainly stream diversion as in the IrrCurrent scenario. The hypothetical IrrGW scenario, in which groundwater withdrawals were the sole source of irrigation water, resulted in widespread lowering of the water table and associated decreases in groundwater storage and groundwater discharge to the stream. A mixing analysis using model predicted groundwater discharge along the reaches suggests that stream diversion and flood irrigation, represented in the IrrCurrent scenario, has led to cooling of stream temperatures relative to natural PreIrr conditions improving fish thermal habitat. However, the decrease in groundwater discharge in the IrrGW scenario resulting from large-scale groundwater withdrawal for irrigation led to warmer than natural stream temperatures and possible degradation of fish habitat. Published by Elsevier B.V.
Essaid, Hedeff I.; Caldwell, Rodney R.
2017-01-01
Changes in groundwater discharge to streams caused by irrigation practices can influence stream temperature. Observations along two currently flood-irrigated reaches in the 640-square-kilometer upper Smith River watershed, an important agricultural and recreational fishing area in west-central Montana, showed a downstream temperature decrease resulting from groundwater discharge to the stream. A watershed-scale coupled surface water and groundwater flow model was used to examine changes in streamflow, groundwater discharge to the stream and stream temperature resulting from irrigation practices. The upper Smith River watershed was used to develop the model framework including watershed climate, topography, hydrography, vegetation, soil properties and current irrigation practices. Model results were used to compare watershed streamflow, groundwater recharge, and groundwater discharge to the stream for three scenarios: natural, pre-irrigation conditions (PreIrr); current irrigation practices involving mainly stream diversion for flood and sprinkler irrigation (IrrCurrent); and a hypothetical scenario with only groundwater supplying sprinkler irrigation (IrrGW). Irrigation increased groundwater recharge relative to natural PreIrr conditions because not all applied water was removed by crop evapotranspiration. Groundwater storage and groundwater discharge to the stream increased relative to natural PreIrr conditions when the source of irrigation water was mainly stream diversion as in the IrrCurrent scenario. The hypothetical IrrGW scenario, in which groundwater withdrawals were the sole source of irrigation water, resulted in widespread lowering of the water table and associated decreases in groundwater storage and groundwater discharge to the stream. A mixing analysis using model predicted groundwater discharge along the reaches suggests that stream diversion and flood irrigation, represented in the IrrCurrent scenario, has led to cooling of stream temperatures relative to natural PreIrr conditions improving fish thermal habitat. However, the decrease in groundwater discharge in the IrrGW scenario resulting from large-scale groundwater withdrawal for irrigation led to warmer than natural stream temperatures and possible degradation of fish habitat.
Virtual water balance estimation in Tunisia
NASA Astrophysics Data System (ADS)
Stambouli, Talel; Benalaya, Abdallah; Ghezal, Lamia; Ali, Chebil; Hammami, Rifka; Souissi, Asma
2015-04-01
The water in Tunisia is limited and unevenly distributed in the different regions, especially in arid zones. In fact, the annual rainfall average varies from less than 100 mm in the extreme South to over 1500 mm in the extreme North of the country. Currently, the conventional potential of water resources of the country is estimated about 4.84 billion m³ / year of which 2.7 billion cubic meters / year of surface water and 2.14 billion cubic meters / year of groundwater, characterizing a structural shortage for water safety in Tunisia (under 500m3/inhabitant/year). With over than 80% of water volumes have been mobilized for agriculture. The virtual water concept, defined by Allan (1997), as the amount of water needed to generate a product of both natural and artificial origin, this concept establish a similarity between product marketing and water trade. Given the influence of water in food production, virtual water studies focus generally on food products. At a global scale, the influence of these product's markets with water management was not seen. Influence has appreciated only by analyzing water-scarce countries, but at the detail level, should be increased, as most studies consider a country as a single geographical point, leading to considerable inaccuracies. The main objective of this work is the virtual water balance estimation of strategic crops in Tunisia (both irrigated and dry crops) to determine their influence on the water resources management and to establish patterns for improving it. The virtual water balance was performed basing on farmer's surveys, crop and meteorological data, irrigation management and regional statistics. Results show that the majority of farmers realize a waste of the irrigation water especially at the vegetable crops and fruit trees. Thus, a good control of the cultural package may result in lower quantities of water used by crops while ensuring good production with a suitable economic profitability. Then, the virtual water concept integration in the production systems choice and policies affecting the use of water is very useful to save over this scarce resource and to support farmers in their production activities and maintaining the sustainability of farms. Keywords: Virtual water, water balance, irrigation, Tunisia
Soil salinity assessment through satellite thermography for different irrigated and rainfed crops
NASA Astrophysics Data System (ADS)
Ivushkin, Konstantin; Bartholomeus, Harm; Bregt, Arnold K.; Pulatov, Alim; Bui, Elisabeth N.; Wilford, John
2018-06-01
The use of canopy thermography is an innovative approach for salinity stress detection in plants. But its applicability for landscape scale studies using satellite sensors is still not well investigated. The aim of this research is to test the satellite thermography soil salinity assessment approach on a study area with different crops, grown both in irrigated and rainfed conditions, to evaluate whether the approach has general applicability. Four study areas in four different states of Australia were selected to give broad representation of different crops cultivated under irrigated and rainfed conditions. The soil salinity map was prepared by the staff of Geoscience Australia and CSIRO Land and Water and it is based on thorough soil sampling together with environmental modelling. Remote sensing data was captured by the Landsat 5 TM satellite. In the analysis we used vegetation indices and brightness temperature as an indicator for canopy temperature. Applying analysis of variance and time series we have investigated the applicability of satellite remote sensing of canopy temperature as an approach of soil salinity assessment for different crops grown under irrigated and rainfed conditions. We concluded that in all cases average canopy temperatures were significantly correlated with soil salinity of the area. This relation is valid for all investigated crops, grown both irrigated and rainfed. Nevertheless, crop type does influence the strength of the relations. In our case cotton shows only minor temperature difference compared to other vegetation classes. The strongest relations between canopy temperature and soil salinity were observed at the moment of a maximum green biomass of the crops which is thus considered to be the best time for application of the approach.
NASA Astrophysics Data System (ADS)
Critto, Andrea; Torresan, Silvia; Ronco, Paolo; Zennaro, Federica; Santini, Monia; Trabucco, Antonio; Marcomini, Antonio
2016-04-01
Climate change is already affecting the frequency of drought events which may threaten the current stocks of water resources and thus the availability of freshwater for the irrigation. The achievement of a sustainable equilibrium between the availability of water resources and the irrigation demand is essentially related to the planning and implementation of evidence-based adaptation strategies and actions. In this sense, the improvement (of existing) and the development of (new) appropriate risk assessment methods and tools to evaluate the impact of drought events on irrigated crops is fundamental in order to assure that the agricultural yields are appropriate to meet the current and future food and market demand. This study evaluates the risk of hydrological drought on the irrigated agronomic compartment of Apulia, a semi-arid region in Southern Italy. We applied a stepwise Regional Risk Assessment (RRA) procedure, based on the consecutive analysis of hazards, exposure, vulnerability and risks, integrating the qualitative and quantitative available information. Future climate projections for the timeframes 2021-2050 and 2041-2070 were provided by COSMO-CLM under the radiative forcing RCP4.5 and RCP8.5. The run-off feeding the water stocks of the most important irrigation reservoirs in Apulia was then modeled with Arc-SWAT. Hence, the hazard analysis was carried out in order to estimate the degree of fulfillment of actual irrigation demand satisfied by water supply of different reservoirs in future scenarios. Vulnerability of exposed irrigated crops was evaluated depending on three factors accounting for crop yield variation vs water stress, water losses along the irrigation network, diversification of water supply. Resulting risk and vulnerability maps allowed: the identification of Reclamation Consortia at higher risk of not fulfilling their future irrigation demand (e.g. Capitanata Reclamation Consortia in RCP8.5 2041-2070 scenario); the ranking of most affected crops (e.g. fruit trees and vineyards); and finally, the characterization of vulnerability pattern of irrigation systems. Major achievements included the definition of a portfolio of science-driven adaptation strategies to reduce the risk pattern at both agronomic level (preferring crops with low vulnerability score, as olive groves) and at structural level (differentiating the water stocks and supplies and reducing losses and inefficiencies).
A Smart Irrigation Approach Aided by Monitoring Surface Soil Moisture using Unmanned Aerial Vehicles
NASA Astrophysics Data System (ADS)
Wienhold, K. J.; Li, D.; Fang, N. Z.
2017-12-01
Soil moisture is a critical component in the optimization of irrigation scheduling in water resources management. Unmanned Aerial Vehicles (UAV) equipped with multispectral sensors represent an emerging technology capable of detecting and estimating soil moisture for irrigation and crop management. This study demonstrates a method of using a UAV as an optical and thermal remote sensing platform combined with genetic programming to derive high-resolution, surface soil moisture (SSM) estimates. The objective is to evaluate the feasibility of spatially-variable irrigation management for a golf course (about 50 acres) in North Central Texas. Multispectral data is collected over the course of one month in the visible, near infrared and longwave infrared spectrums using a UAV capable of rapid and safe deployment for daily estimates. The accuracy of the model predictions is quantified using a time domain reflectometry (TDR) soil moisture sensor and a holdout validation test set. The model produces reasonable estimates for SSM with an average coefficient of correlation (r) = 0.87 and coefficient of determination of (R2) = 0.76. The study suggests that the derived SSM estimates be used to better inform irrigation scheduling decisions for lightly vegetated areas such as the turf or native roughs found on golf courses.
NASA Astrophysics Data System (ADS)
Li, Yuan; Jia, Zong-xia; Niu, Wen-Quan; Wang, Jing-wei
2016-07-01
Sensitivity to low rhizosphere soil aeration may change over time and therefore plant response may also depend on different growth stages of a crop. This study quantified effects of soil aeration during 5 different periods, on growth and yield of trickle-irrigated potted single tomato plants. Irrigation levels were 0.6 to 0.7 (low level) or 0.7 to 0.8 (high level) of total water holding capacity of the pots. Soil was aerated by injecting 2.5 l of air into each pot through the drip tubing immediately after irrigation. Fresh fruit yield, above ground plant dry weight, plant height, and leaf area index response to these treatments were measured. For all these 4 response variables, means of post-infiltration aeration between 58 to 85 days after sowing were 13.4, 43.5, 13.7, and 37.7% higher than those for the non-aerated pots, respectively. The results indicated that: post-infiltration soil aeration can positively impact the yield and growth of sub-surface trickle-irrigated potted tomato plants; positive effects on plant growth can be obtained with aeration during the whole growth period or with aeration for partial periods; positive growth effects of partial periods of aeration appears to persist and result in yield benefit.
NASA Astrophysics Data System (ADS)
Rapp, J. R.; Deines, J. M.; Kendall, A. D.; Hyndman, D. W.
2017-12-01
The High Plains Aquifer (HPA) is the most extensively irrigated aquifer in the continental United States and is the largest major aquifer in North America with an area of 500,000 km2. Increased demand for agricultural products has led to expanded irrigation extent, but brought with it declining groundwater levels that have made irrigation unsustainable in some locations. Understanding these irrigation dynamics and mapping irrigated areas through time are essential for future sustainable agricultural practices and hydrological modeling. Map products using remote sensing have only recently been able to track annual dynamics at relatively high spatial resolution (30 m) for a large portion of the northern HPA. However follow-on efforts to expand these maps to the entire HPA have met with difficulty due to the challenge of distinguishing irrigation in crop types that are commonly deficit- or partially-irrigated. Expanding these maps to the full HPA requires addressing unique features of partially irrigated fields and irrigated cotton, a major water user in the southern HPA. Working in Google Earth Engine, we used all available Landsat imagery to generate annual time series of vegetation indices. We combined this information with climate covariables, planting dates, and crop specific training data to algorithmically separate fully irrigated, partially irrigated, and non-irrigated field locations. The classification scheme was then applied to produce annual maps of irrigation across the entire HPA. The extensive use of ancillary data and the "greenness" time series for the algorithmic classification generally increased accuracy relative to previous efforts. High-accuracy, representative map products of irrigation extent capable of detecting crop type and irrigation intensity within aquifers will be an essential tool to monitor the sustainability of global aquifers and to provide a scientific bases for political and economic decisions affecting those aquifers.
Evaluating deficit irrigation management strategies for grain sorghum using AquaCrop
USDA-ARS?s Scientific Manuscript database
Many wells in the US Central Plains can no longer meet full crop water requirements due to declines in Ogallala aquifer water levels. A study was conducted in Southwest Kansas to determine optimum limited irrigation strategies for grain sorghum. Objectives were to (1) calibrate and validate the Aqua...
7 CFR 1437.104 - Assigned production.
Code of Federal Regulations, 2011 CFR
2011-01-01
.... (4) The crop is planted after the STC-established final planting date according to § 1437.103. (5) Irrigation equipment is not capable of supplying adequate water to sustain the expected production of a... practice is not used. (7) For normal irrigated annual and biennial crops, the supply of available water at...
Deficit irrigation: Arriving at the crop water stress index via gas exchange measurements
USDA-ARS?s Scientific Manuscript database
Plant gas exchange provides a highly sensitive measure of the degree of drought stress. Canopy temperature (Tc) provides a much easier to acquire indication of crop water deficit that has been used in irrigation scheduling systems, but interpretation of this measurement has proven difficult. Our goa...
Vegetable Response to Herbicides Applied to Low-Density Polyethylene Mulch Prior to Transplant
USDA-ARS?s Scientific Manuscript database
Few herbicides are available for weed control in vegetables. The elimination of methyl bromide increases the need for herbicides. An experiment was conducted to evaluate crop injury from herbicides applied to LDPE mulch prior to transplant. Irrigation (1 cm) or no irrigation following crop transplan...
43 CFR 2610.0-5 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-10-01
... irrigation as an attendant act. (c) Desert lands means unreclaimed lands which will not, without irrigation... ordinary crop of hay in usual seasons, are not desert lands. Lands which will produce an agricultural crop... are not desert. Lands containing sufficient moisture to produce a natural growth of trees are not to...
43 CFR 2610.0-5 - Definitions.
Code of Federal Regulations, 2012 CFR
2012-10-01
... irrigation as an attendant act. (c) Desert lands means unreclaimed lands which will not, without irrigation... ordinary crop of hay in usual seasons, are not desert lands. Lands which will produce an agricultural crop... are not desert. Lands containing sufficient moisture to produce a natural growth of trees are not to...
43 CFR 2610.0-5 - Definitions.
Code of Federal Regulations, 2013 CFR
2013-10-01
... irrigation as an attendant act. (c) Desert lands means unreclaimed lands which will not, without irrigation... ordinary crop of hay in usual seasons, are not desert lands. Lands which will produce an agricultural crop... are not desert. Lands containing sufficient moisture to produce a natural growth of trees are not to...
Investigating strategies to improve crop germination when using SDI
USDA-ARS?s Scientific Manuscript database
As the nation's population increases and available irrigation water decreases, new technologies are being developed to maintain or increase production on fewer acres. One of these advancements has been the use of subsurface drip irrigation (SDI) on field crops. Research has shown that SDI is the m...
Integrated Adaptive Scenarios for Ariculture: Synergies and Tradeoffs.
NASA Astrophysics Data System (ADS)
Malek, K.; Rajagopalan, K.; Adam, J. C.; Brady, M.; Stockle, C.; Liu, M.; Kruger, C. E.
2017-12-01
A wide variety of factors can drive adaptation of the agricultural production sector in response to climate change. Warming and increased growing season length can lead to adoption of newer plant varieties as well as increases in double cropping systems. Changes in expectations of drought frequency or economic factors could lead to adoption of new technology (such as irrigation technology or water trading systems) or crop choices with a view of reducing farm-level risk, and these choices can result in unintended system wide effects. These are all examples of producer adaptation decisions made with a long-term (multiple decades) view. In addition, producers respond to short-term (current year) shocks - such as drought events - through management strategies that include deficit irrigation, fallowing, nutrient management, and engaging in water trading. The effects of these short- and long-term decisions are not independent, and can drive or be driven by the other. For example, investment in new irrigation systems (long-term) can be driven by expectations of short-term crop productivity losses in drought years. Similarly, the capacity to manage for short-term shocks will depend on crop type and variety as well as adopted irrigation technologies. Our overarching objective is to understand the synergies and tradeoffs that exist when combining three potential long-term adaptation strategies and two short-term adaptation strategies, with a view of understanding the synergies and tradeoffs. We apply the integrated crop-hydrology modeling framework VIC-CropSyst, along with the water management module Yakima RiverWare to address these questions over our test area, the Yakima River basin. We consider adoption of a) more efficient irrigation technologies, slower growing crop varieties, and increased prevalence of double cropping systems as long-term adaptation strategies; and b) fallowing and deficit irrigation as short-term responses to droughts. We evaluate the individual and combined effect of these strategies on agricultural production. Preliminary results indicate that long-term adaptation strategies impact short-run adaptive capacities to drought shocks. The strategies are complementary under certain situations and results in tradeoffs in other situations, and we characterize these differences.
Synergetic Use of Sentinel-1 and 2 to Improve Agro-Hydrological Modeling
NASA Astrophysics Data System (ADS)
Ferrant, Sylvain; Kerr, Yann; Al-Bitar, Ahmad; Le Page, Michel; Selles, Adrien; Mermoz, Stephane; Bouvet, Alexandre; Marechal, Jean-Christophe; Tomer, Sat; Sekhar, Muddu; Dedieu, Gerard; Le Toan, Thuy; Bustillo, Vincent
2016-08-01
In the context of global changes and population growth, agricultural activities are a growing factor influencing water resources availability in term of quantity and quality. Water management strategies have to be analyzed at a regional catchment scales. Yet, agricultural practices, crop water and nutrient consumption that drive the main water and nutrient fluxes at the catchment scale have to be monitored at a high spatial (crop extension) and temporal resolution (crop growth period). This proceeding describes some advances in the framework of a co-funded ESA Living Planet Fellowship project, called ―agro-hydrology from space‖, which aims at demonstrating the improvement brought by synergetic observations of Sentinel-1 (S1) and Sentinel-2 (S2) satellite mission in agro- hydrological studies. Geo-information time-series of vegetation and water index with multi-spectral optical detection S2 together with surface roughness time series with C-band radar detection S1 are used to re-set soil water holding capacity parameters (depth, porosity) and agricultural practices (sowing date, irrigated area extent) of a crop model coupled with a hydrological model in two contrasted water management issues: stream water nitrate pollution in Gascogne region in south-west of France and groundwater depletion and shortages for irrigation in Deccan Plateau, in south-India.
NASA Astrophysics Data System (ADS)
Ghazouani, Hiba; Autovino, Dario; Douh, Boutheina; Boujelben, Abdel Hamid; Provenznao, Giuseppe; Rallo, Giovanni
2014-05-01
The main objective of the work is to assess the emitters optimal position for Eggplant crop (Solanum melongena L.) in a sandy loam soil irrigated with surface or subsurface drip irrigation systems, by means of field measurements and simulations carried out with Hydrus-2D model. Initially, the performance of the model is evaluated on the basis of the comparison between simulated soil water contents (SWC) and the corresponding measured in two plots, in which laterals with coextruded emitters are laid on the soil surface (T0) and at 20 cm depth (T20), respectively. In order to choose the best position of the lateral, the results of different simulation runs, carried out by changing the installation depth of the lateral (5 cm, 15 cm and 45 cm) were compared in terms of ratio between actual transpiration and total amount of water provided during the entire growing season (WUE). Experiments were carried out, from April to June 2007, at Institut Supérieur Agronomique de Chott Mériem (Sousse, Tunisia). In the two plots, plants were spaced 0.40 m along the row and 1.2 m between the rows. Each plot was irrigated by means of laterals with coextruded emitters spaced 0.40 m and discharging a flow rate equal to 4.0 l h-1 at a nominal pressure of 100 kPa. In each plot, spatial and temporal variability of SWCs were acquired with a Time Domain Reflectometry probe (Trime-FM3), on a total of four 70 cm long access tubes, installed along the direction perpendicular to the plant row, at distances of 0, 20, 40 and 60 cm from the emitter. Irrigation water was supplied, accounting for the rainfall, every 7-10 days at the beginning of the crop cycle (March-April) and approximately once a week during the following stages till the harvesting (May-June), for a total of 15 one-hour watering. To run the model, soil evaporation, Ep, and crop transpiration, Tp were determined according to the modified FAO Penman-Monteith equation and the dual crop coefficient approach, whereas soil hydraulics and rooting system parameters were experimentally determined. Simulated SWCs resulted fairly close to the corresponding measured at different distances from the emitter and therefore the model was able to predict SWCs in the root zone with values of the Root Mean Square Error generally lower than 4%. This result is consequent to the appropriate schematization of the root distribution, as well as of the root water uptake. Simulations also evidenced the contribute of soil evaporation losses when laterals are installed from the soil surface to a 20 cm depth, whereas significant water losses by deep percolation occured at the highest installation depth. The values of WUE associated to the different examined installation depths tend to a very slight increase when the position of the lateral rises from 0 to 15 cm and start to decrease for the higher depths.
NASA Astrophysics Data System (ADS)
Yu, B.; Shang, S.
2016-12-01
Food shortage is one of the major challenges that human beings are facing. It is urgent to improve the monitoring of the plantation and distribution of the main crops to solve the following economic and social issues. Recently, with the extensive use of remote sensing satellite data, it has provided favorable conditions for crop identification in large irrigation district with complex planting structure. Difference of different crop phenology is the main basis for crop identification, and the normalized difference vegetation index (NDVI) time-series could better delineate crop phenology cycle. Therefore, the key of crop identification is to obtain high quality NDVI time-series. MODIS and Landsat TM satellite images are the most frequently used, however, neither of them could guarantee high temporal and spatial resolutions at once. Accordingly, this paper makes use of NDVI time-series extracted from China Environment Satellites data, which has two-day-repeat temporal and 30m spatial resolutions. The NDVI time-series are fitted with an asymmetric logistic curve, the fitting effect is good and the correlation coefficient is greater than 0.9. The phonological parameters are derived from NDVI fitting curves, and crop identification is carried out by different relation ellipses between NDVI and its phonological parameters of different crops. This paper takes Hetao Irrigation District of Inner Mongolia as an example, to identify multi-year maize and sunflower in the district, and the identification result is good. Compared with the official statistics, the relative errors are both lower than 5%. The results show that the NDVI time-series dataset derived from HJ-1A/1B CCD could delineate the crop phenology cycle accurately and demonstrate its application in crop identification in irrigated district.
Marella, Richard L.; Dixon, Joann F.
2015-09-18
The irrigated acreage estimated for Jackson County in 2014 (31,608) is about 47 percent higher than the 2012 estimated acreage published by the USDA (21,508 acres). The estimates of irrigated acreage field verified during 2014 for Calhoun and Gadsden Counties are also higher than those published by the USDA for 2012 (86 percent and 71 percent, respectively). In Calhoun County the USDA reported 1,647 irrigated acres while the current study estimated 3,060 acres, and in Gadsden County the USDA reported 2,650 acres while the current study estimated 4,547 acres. For Houston County the USDA-reported value of 9,138 acres in 2012 was 13 percent below the 10,333 acres field verified in the current study. Differences between the USDA 2012 values and 2014 field verified estimates in these two datasets may occur because (1) irrigated acreage for some specific crops increased or decreased substantially during the 2-year interval due to commodity prices or economic changes, (2) irrigated acreage calculated for the current study may be estimated high because irrigation was assumed if an irrigation system was present and therefore the acreage was counted as irrigated, when in fact that may not have been the case as some farmers may not have used their irrigation systems during this growing period even if they had a crop in the field, or (3) the amount of irrigated acreages published by the USDA for selected crops may be underestimated in some cases.
Johnson, A. W.; Young, J. R.; Wright, W. C.
1986-01-01
Phenamiphos (6.7 kg a.i./ha) was applied via an irrigation simulator to squash at planting (AP) and 2 weeks after planting (PP), and to corn AP and 1 week PP to manage root-knot nematodes (Meloidogyne incognita). The nematicide was applied with 0.25, 0.64, 1.27, and 1.91 cm surface water/ ha to a Lakeland sand in which the soil moisture was at or near field capacity. Based on efficacy and crop response, no additional benefits resulted when phenamiphos was applied in volumes of water greater than 0.25 crn/ha. The cost of applying each 0.25 cm of water over a hectare is approximately $1.08, or a 92% reduction in nematicide application cost over conventional methods ($13.50/ha). Low root-gall indices and high yields from squash and corn indicate more effective nematode management when phenamiphos was applied AP rather than PP. Results from this method of applying phenamiphos suggest that certain nematicides could be used as salvage alternatives when nematodes are detected in crops soon after planting. For multiple-pest management, nematicides, other compatible biocides, and fertilizers could be applied simultaneously with sprinkler irrigation. PMID:19294192
Chiou, Ren-Jie
2008-07-01
The reuse of treated municipal wastewater should be one of the new water resource target areas. The suitability of the reuse of wastewater for agricultural irrigation has to consider health risk, soil contamination and the influence of the reclaimed water on crop growth. In this work the aim is to use quantitative risk analysis to assess the health effects related to reclaimed water quality and to calculate the loading capacity of reclaimed wastewater in terms of the heavy metal accumulation. The results of chemical risk assessment show there would be slightly significant health risk and what risk there is can be limited within an acceptable level. The following exposure pathway: reclaimed water-->surface water-->fish (shellfish)-->human, and arsenic risks are of more concern. In terms of reuse impact in soil contamination, the most possible heavy metal caused accumulation is arsenic. The irrigative quantity has to reach 13,300 m(3)/ha to cause arsenic accumulation. However, only 12,000 m(3)/ha is essential for rice paddy cropland. The high total nitrogen of reclaimed water from secondary treatment makes it unfavorable for crop growth. The recommended dilution ratio is 50% during the growth period and 25% during the maturity period.
NASA Astrophysics Data System (ADS)
Zaragosa, I.; Melton, F. S.; Dexter, J.; Post, K.; Haffa, A.; Kortman, S.; Spellenberg, R.; Cahn, M.
2017-12-01
In efforts to provide tools to allow farmers to optimize and quantify water usage and fertilizer applications, University of California Cooperative Extension (UCCE) developed the CropManage irrigation and nitrogen scheduling tool that provides real time evapotranspiration (ETc) based irrigation recommendations and fertilizer recommendations on a per field basis. CropManage incorporates satellite based estimates of fractional cover from web data services from the Satellite Irrigation Management Information Support (SIMS) system developed by NASA Ames Research Center in collaboration with California State University Monterey Bay (CSUMB). In this study, we conducted field trials to quantify the benefits of using these tools to support best management practices (BMPs) for irrigation and nutrient management in strawberries and lettuce in the Salinas Valley, California. We applied two different irrigation treatments based on full replacement (100%) of crop evapotranspiration (ETc), and irrigation at 130% of ETc replacement to approximate irrigation under business as usual irrigation management. Both field studies used a randomized block design with four replicates each. We used CropManage to calculate the 100% and 130% ETc replacement requirements prior to each irrigation event. We collected drainage volume and samples and analyzed them for 8500 to nitrate as (NO3-) concentrations. Experimental results for both strawberries and lettuce showed a significant decrease in the percentage of applied nitrogen leached for the 100% ETc replacement treatment against the 130% ETc replacement treatment. For strawberries, we observed that 24% of applied nitrogen was leached under the 100% ETc replacement treatment, versus 51% of applied nitrogen that was leached under the 130% ETc replacement treatment. For lettuce, we observe that 2% of the applied nitrogen leached bellow the soil profile, versus 6% of the applied nitrogen for the 130%ETc replacement treatment. In both experiments, we observed significant differences in the amount of leached nitrogen, both as in terms of total volume and as a percent of nitrogen applied, with no significant differences in yield.
Gumma, Murali Krishna; Thenkabail, Prasad S.; Muralikrishna, I.V.; Velpuri, Naga Manohar; Gangadhararao, P.T.; Dheeravath, V.; Biradar, C.M.; Nalan, S.A.; Gaur, A.
2011-01-01
The objective of this study was to investigate the changes in cropland areas as a result of water availability using Moderate Resolution Imaging Spectroradiometer (MODIS) 250 m time-series data and spectral matching techniques (SMTs). The study was conducted in the Krishna River basin in India, a very large river basin with an area of 265 752 km2 (26 575 200 ha), comparing a water-surplus year (2000–2001) and a water-deficit year (2002–2003). The MODIS 250 m time-series data and SMTs were found ideal for agricultural cropland change detection over large areas and provided fuzzy classification accuracies of 61–100% for various land‐use classes and 61–81% for the rain-fed and irrigated classes. The most mixing change occurred between rain-fed cropland areas and informally irrigated (e.g. groundwater and small reservoir) areas. Hence separation of these two classes was the most difficult. The MODIS 250 m-derived irrigated cropland areas for the districts were highly correlated with the Indian Bureau of Statistics data, with R 2-values between 0.82 and 0.86.The change in the net area irrigated was modest, with an irrigated area of 8 669 881 ha during the water-surplus year, as compared with 7 718 900 ha during the water-deficit year. However, this is quite misleading as most of the major changes occurred in cropping intensity, such as changing from higher intensity to lower intensity (e.g. from double crop to single crop). The changes in cropping intensity of the agricultural cropland areas that took place in the water-deficit year (2002–2003) when compared with the water-surplus year (2000–2001) in the Krishna basin were: (a) 1 078 564 ha changed from double crop to single crop, (b) 1 461 177 ha changed from continuous crop to single crop, (c) 704 172 ha changed from irrigated single crop to fallow and (d) 1 314 522 ha changed from minor irrigation (e.g. tanks, small reservoirs) to rain-fed. These are highly significant changes that will have strong impact on food security. Such changes may be expected all over the world in a changing climate.
SEBAL Model Using to Estimate Irrigation Water Efficiency & Water Requirement of Alfalfa Crop
NASA Astrophysics Data System (ADS)
Zeyliger, Anatoly; Ermolaeva, Olga
2013-04-01
The sustainability of irrigation is a complex and comprehensive undertaking, requiring an attention to much more than hydraulics, chemistry, and agronomy. A special combination of human, environmental, and economic factors exists in each irrigated region and must be recognized and evaluated. A way to evaluate the efficiency of irrigation water use for crop production is to consider the so-called crop-water production functions, which express the relation between the yield of a crop and the quantity of water applied to it or consumed by it. The term has been used in a somewhat ambiguous way. Some authors have defined the Crop-Water Production Functions between yield and the total amount of water applied, whereas others have defined it as a relation between yield and seasonal evapotranspiration (ET). In case of high efficiency of irrigation water use the volume of water applied is less than the potential evapotranspiration (PET), then - assuming no significant change of soil moisture storage from beginning of the growing season to its end-the volume of water may be roughly equal to ET. In other case of low efficiency of irrigation water use the volume of water applied exceeds PET, then the excess of volume of water applied over PET must go to either augmenting soil moisture storage (end-of-season moisture being greater than start-of-season soil moisture) or to runoff or/and deep percolation beyond the root zone. In presented contribution some results of a case study of estimation of biomass and leaf area index (LAI) for irrigated alfalfa by SEBAL algorithm will be discussed. The field study was conducted with aim to compare ground biomass of alfalfa at some irrigated fields (provided by agricultural farm) at Saratov and Volgograd Regions of Russia. The study was conducted during vegetation period of 2012 from April till September. All the operations from importing the data to calculation of the output data were carried by eLEAF company and uploaded in Fieldlook web geo database and used for experiment program managment. Quite good agreement between measured and calculated biomass and LAI were obtained. Estimation of effectiveness of water efficiency as well as estimation of applied water losses were done in the base of supplied irrigation water provided by local operating irrigation water supply companies and data of soil moisture monitoring. Following analyse of the remote sensing use to estimate of crop water requirement will be presented. ACKNOWLEDGMENTS. This study was financially supported by G2G project
Estimated water use in Puerto Rico, 2000
Molina-Rivera, Wanda L.
2005-01-01
Water-use data were compiled for the 78 municipios of the Commonwealth of Puerto Rico for 2000. Five offstream categories were considered: public-supply water withdrawals, domestic self-supplied water use, industrial self-supplied withdrawals, crop irrigation water use, and thermoelectric power fresh water use. Two additional categories also were considered: power generation instream use and public wastewater treatment return-flows. Fresh water withdrawals for offstream use from surface- and ground-water sources in Puerto Rico were estimated at 617 million gallons per day. The largest amount of fresh water withdrawn was by public-supply water facilities and was estimated at 540 million gallons per day. Fresh surface- and ground-water withdrawals by domestic self-supplied users was estimated at 2 million gallons per day and the industrial self-supplied withdrawals were estimated at 9.5 million gallons per day. Withdrawals for crop irrigation purposes were estimated at 64 million gallons per day, or approximately 10 percent of all offstream fresh water withdrawals. Saline instream surface-water withdrawals for cooling purposes by thermoelectric power facilities was estimated at 2,191 million gallons per day, and instream fresh water withdrawals by hydroelectric facilities at 171 million gallons per day. Total discharge from public wastewater treatment facilities was estimated at 211 million gallons per day.
Chung, N J; Cho, J Y; Park, S W; Park, B J; Hwang, S A; Park, T I
2008-08-01
The effects of domestic wastewater application on the translocation and accumulation of polycyclic aromatic hydrocarbons (PAHs) in soil and crops (rice, lettuce, and barley) were investigated by Wagner's pot experiment. In the soils and crops after domestic wastewater irrigation, high-molecular weight PAHs (5 to 6 ring) were not detected, but low-molecular weight PAHs (3 to 4 ring) were only detected at trace levels.
Influence of crop load on almond tree water status and its importance in irrigation scheduling
NASA Astrophysics Data System (ADS)
Puerto Conesa, Pablo; Domingo Miguel, Rafael; Torres Sánchez, Roque; Pérez Pastor, Alejandro
2014-05-01
In the Mediterranean area water is the main factor limiting crop production and therefore irrigation is essential to achieve economically viable yields. One of the fundamental techniques to ensure that irrigation water is managed efficiently with maximum productivity and minimum environmental impact is irrigation scheduling. The fact that the plant water status integrates atmospheric demand and soil water content conditions encourages the use of plant-based water status indicators. Some researchers have successfully scheduled irrigation in certain fruit trees by maintaining the maximum daily trunk diameter shrinkage (MDS) signal intensity at threshold values to generate (or not) water stress. However MDS not only depends on the climate and soil water content, but may be affected by tree factors such as age, size, phenological stage and fruit load. There is therefore a need to quantify the influence of these factors on MDS. The main objective of this work was to study the effects of crop load on tree water relations for scheduling purposes. We particularly focused on MDS vs VPD10-15 (mean air vapor pressure deficit during the period 10.00-15.00 h solar time) for different loads and phenological phases under non-limiting soil water conditions. The experiment was carried out in 2011 in a 1 ha plot in SE Spain with almond trees (Prunus dulcis (Mill.) D.A. Webb cv. 'Marta'). Three crop load treatments were studied according to three crop load levels, i) T100, high crop load, characteristic crop load, ii) T50, medium crop load, in which 50% of the fruits were removed and iii) T0, practically without fruits. Fruits were manually thinned. Each treatment, randomly distributed in blocks, was run in triplicate. Plant water status was assessed from midday stem water potential (Ψs), MDS, daily trunk growth rate (TGR), leaf turgor potential Ψp, fruit water potential (Ψf), stomatal conductance (gs) and photosynthesis (Pn) and transpiration rates (E). Yield, pruning weights and reserve sugar concentration were also evaluated. Trees were drip irrigated in order to satisfy the maximum crop water requirements. Variations in MDS were compared with changes in Ψs and VPD10-15 in the three treatments at the end of fruit growth stage (stage III), kernel filling stage (stage IV) and postharvest (stage V). Our results highlighted that crop load affects almond tree water status. We observed a greater effect of crop load on MDS and TGR than on Ψs. In T0 trees, Ψs was 16% higher than in T50 and T100. MDS was 36% and 49% lower in the low (T50) and almost nil-cropping trees (T0) than in the high-cropping trees (T100). The slope of MDS vs VPD10-15 forced to the origin increased with crop load, suggesting that different relationships are needed to estimate tree water status. TGR was 33% higher in T0 than in the cropping trees. In the same way, the presence of fruits, as reflected by the source/sink relationship, increased gas exchange parameters. Also pruning weights reflected competition between fruits and shoots for photoassimilates. Nevertheless the reserve sugar concentration at the base of the main branches was unaffected by the crop load. All this implies that it is necessary to consider the crop load in irrigation scheduling based on MDS signal intensity.
Schmidt, Anja; John, Katharina; Arida, Gertrudo; Auge, Harald; Brandl, Roland; Horgan, Finbarr G; Hotes, Stefan; Marquez, Leonardo; Radermacher, Nico; Settele, Josef; Wolters, Volkmar; Schädler, Martin
2015-01-01
Decomposers provide an essential ecosystem service that contributes to sustainable production in rice ecosystems by driving the release of nutrients from organic crop residues. During a single rice crop cycle we examined the effects of four different crop residue management practices (rice straw or ash of burned straw scattered on the soil surface or incorporated into the soil) on rice straw decomposition and on the abundance of aquatic and soil-dwelling invertebrates. Mass loss of rice straw in litterbags of two different mesh sizes that either prevented or allowed access of meso- and macro-invertebrates was used as a proxy for decomposition rates. Invertebrates significantly increased total loss of litter mass by up to 30%. Initially, the contribution of invertebrates to decomposition was significantly smaller in plots with rice straw scattered on the soil surface; however, this effect disappeared later in the season. We found no significant responses in microbial decomposition rates to management practices. The abundance of aquatic fauna was higher in fields with rice straw amendment, whereas the abundance of soil fauna fluctuated considerably. There was a clear separation between the overall invertebrate community structure in response to the ash and straw treatments. However, we found no correlation between litter mass loss and abundances of various lineages of invertebrates. Our results indicate that invertebrates can contribute to soil fertility in irrigated paddy fields by decomposing rice straw, and that their abundance as well as efficiency in decomposition may be promoted by crop residue management practices.
Schmidt, Anja; John, Katharina; Arida, Gertrudo; Auge, Harald; Brandl, Roland; Horgan, Finbarr G.; Hotes, Stefan; Marquez, Leonardo; Radermacher, Nico; Settele, Josef; Wolters, Volkmar; Schädler, Martin
2015-01-01
Decomposers provide an essential ecosystem service that contributes to sustainable production in rice ecosystems by driving the release of nutrients from organic crop residues. During a single rice crop cycle we examined the effects of four different crop residue management practices (rice straw or ash of burned straw scattered on the soil surface or incorporated into the soil) on rice straw decomposition and on the abundance of aquatic and soil-dwelling invertebrates. Mass loss of rice straw in litterbags of two different mesh sizes that either prevented or allowed access of meso- and macro-invertebrates was used as a proxy for decomposition rates. Invertebrates significantly increased total loss of litter mass by up to 30%. Initially, the contribution of invertebrates to decomposition was significantly smaller in plots with rice straw scattered on the soil surface; however, this effect disappeared later in the season. We found no significant responses in microbial decomposition rates to management practices. The abundance of aquatic fauna was higher in fields with rice straw amendment, whereas the abundance of soil fauna fluctuated considerably. There was a clear separation between the overall invertebrate community structure in response to the ash and straw treatments. However, we found no correlation between litter mass loss and abundances of various lineages of invertebrates. Our results indicate that invertebrates can contribute to soil fertility in irrigated paddy fields by decomposing rice straw, and that their abundance as well as efficiency in decomposition may be promoted by crop residue management practices. PMID:26225556
NASA Astrophysics Data System (ADS)
Albano, Raffaele; Manfreda, Salvatore; Celano, Giuseppe
The paper introduces a minimalist water-driven crop model for sustainable irrigation management using an eco-hydrological approach. Such model, called MY SIRR, uses a relatively small number of parameters and attempts to balance simplicity, accuracy, and robustness. MY SIRR is a quantitative tool to assess water requirements and agricultural production across different climates, soil types, crops, and irrigation strategies. The MY SIRR source code is published under copyleft license. The FOSS approach could lower the financial barriers of smallholders, especially in developing countries, in the utilization of tools for better decision-making on the strategies for short- and long-term water resource management.
Liu, Jing; Wu, Pute; Wang, Yubao; Zhao, Xining; Sun, Shikun; Cao, Xinchun
2014-11-01
Analysis of cropping patterns is a prerequisite for their optimisation, and evaluation of virtual water flows could shed new light on water resources management. This study is intended to explore the effects of cropping pattern changes between 1960 and 2008 on virtual water flows related to crops transfer in the Hetao irrigation district, China. (1) The sown area of crops increased at an average rate of 3.57 × 10(3) ha year(-1) while the proportion of sown grain crops decreased from 92.83% in the 1960s to 50.22% in the 2000s. (2) Virtual water content decreased during the study period while net virtual water exports increased since the 1980s. (3) Assuming that the cropping pattern was constant and was equal to the average 1960s value, accumulated net virtual water export in 1980-2008 would have been 4.76 × 10(9) m(3) greater than that in the actual cropping pattern scenario. Cropping pattern changes in the Hetao irrigation district could not only be seen as resulting from the pursuit for higher economic returns, but also as a feedback response to limited water resources. A systematic framework is still needed for future cropping pattern planning by taking food security, continued agricultural expansion and other constraints into consideration. © 2014 Society of Chemical Industry.
UV Light Inactivation of Human and Plant Pathogens in Unfiltered Surface Irrigation Water
Jones, Lisa A.; Worobo, Randy W.
2014-01-01
Fruit and vegetable growers continually battle plant diseases and food safety concerns. Surface water is commonly used in the production of fruits and vegetables and can harbor both human- and plant-pathogenic microorganisms that can contaminate crops when used for irrigation or other agricultural purposes. Treatment methods for surface water are currently limited, and there is a need for suitable treatment options. A liquid-processing unit that uses UV light for the decontamination of turbid juices was analyzed for its efficacy in the treatment of surface waters contaminated with bacterial or oomycete pathogens, i.e., Escherichia coli, Salmonella enterica, Listeria monocytogenes, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, and Phytophthora capsici. Five-strain cocktails of each pathogen, containing approximately 108 or 109 CFU/liter for bacteria or 104 or 105 zoospores/liter for Ph. capsici, were inoculated into aliquots of two turbid surface water irrigation sources and processed with the UV unit. Pathogens were enumerated before and after treatment. In general, as the turbidity of the water source increased, the effectiveness of the UV treatment decreased, but in all cases, 99.9% or higher inactivation was achieved. Log reductions ranged from 10.0 to 6.1 and from 5.0 to 4.2 for bacterial pathogens and Ph. capsici, respectively. PMID:24242253
UV light inactivation of human and plant pathogens in unfiltered surface irrigation water.
Jones, Lisa A; Worobo, Randy W; Smart, Christine D
2014-02-01
Fruit and vegetable growers continually battle plant diseases and food safety concerns. Surface water is commonly used in the production of fruits and vegetables and can harbor both human- and plant-pathogenic microorganisms that can contaminate crops when used for irrigation or other agricultural purposes. Treatment methods for surface water are currently limited, and there is a need for suitable treatment options. A liquid-processing unit that uses UV light for the decontamination of turbid juices was analyzed for its efficacy in the treatment of surface waters contaminated with bacterial or oomycete pathogens, i.e., Escherichia coli, Salmonella enterica, Listeria monocytogenes, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, and Phytophthora capsici. Five-strain cocktails of each pathogen, containing approximately 10(8) or 10(9) CFU/liter for bacteria or 10(4) or 10(5) zoospores/liter for Ph. capsici, were inoculated into aliquots of two turbid surface water irrigation sources and processed with the UV unit. Pathogens were enumerated before and after treatment. In general, as the turbidity of the water source increased, the effectiveness of the UV treatment decreased, but in all cases, 99.9% or higher inactivation was achieved. Log reductions ranged from 10.0 to 6.1 and from 5.0 to 4.2 for bacterial pathogens and Ph. capsici, respectively.
Abu-Dieyeh, Mohammed H; Diab, Mahmoud; Al-Ghouti, Mohammad A
2017-06-01
The goal of this study was to evaluate the impact of using yeast wastewater (YW) on weed communities. The study showed that all ecological parameters including species richness, dispersion, density, frequency, and % of vegetation cover were significantly increased in the site irrigated with YW compared to a natural rain fed site and another site irrigated with fresh water. The vegetation cover (%) was significantly increased by 2-folds in the site irrigated with YW (52%) than the one irrigated with fresh water (27%). Species richness increases to 23 in the site irrigated with yeast wastewater compared to 12 species in natural rain fed site and 7 species in areas irrigated with fresh water. The 10 studied weed species germinated better at 10 and 20% dilutions of baker's YW. However, only five species achieved few germination (3-25%) at 50% of YW and the two species Sisymbrim irio and Cardariia droba achieved (6-13%) germination using 100% YW. No germination occurred for the crop seeds (tomato, squash, lentil, and barley) at 50 and 100% YW. For tomato, 10 and 20% of YW achieved better germination (82 and 63%, respectively) than the seeds of other species, followed by barley with 80 and 53% of germination. Squash showed the lowest germination percentage with 59 and 42% at 10 and 20% of YW, respectively. Yeast wastewater seems to be crop specific and can affect weed species composition and relative abundances and care should be taken before using the effluent for irrigation of tree plantations and crops.
Willingness to pay for more efficient irrigation techniques in the Lake Karla basin, Greece.
NASA Astrophysics Data System (ADS)
Mylopoulos, Nikitas; Fafoutis, Chrysostomos
2014-05-01
Thessaly, the second largest plain of Greece, is an intensively cultivated agricultural region. The intense and widespread agriculture of hydrophilic crops, such as cotton, has led to a remarkable water demand increase, which is usually covered by the overexploitation of groundwater resources. The Lake Karla basin is a prominent example of this unsustainable practice. Competition for the limited available freshwater resources in the Lake Karla basin is expected to increase in the near future as demand for irrigation water increases and drought years are expected to increase due to climate change. Together with the Unions of Agricultural Cooperatives, the Local Organizations of Land Reclamation is planning to introduce more efficient, water saving automated drip irrigation in the area among farmers who currently use non-automated drip irrigation, in order to ensure that these farmers can better cope with drought years and that water will be used more efficiently in crop production. Saving water use in irrigated agriculture is expected to be beneficial to both farmers and the restoration of Lake Karla and its wildlife like plants and birds. The aim of this study is to understand and record the farmers' opinions regarding the use of irrigation water and the restoration of Lake Karla, and to extract valuable conclusions and perform detailed analysis of the criteria for a new irrigation method. A general choice experiment with face-to-face interviews was conducted, using a random sample of 150 open field farmers from the study area. The farmers, who use the non-automated drip irrigation method and their farms are located within the watershed of Lake Karla, were interviewed regarding their willingness to switch to more efficient irrigation techniques, such as automated and controlled drip irrigation.The most important benefits of automated drip irrigation are an increase in crop yield, as plants are given water in a more precise way (based on their needs during the growing season) and a saving in water use. The choice experiment displays to the farmers two possible options for automated drip irrigation, described in terms of expected increase in crop yield, expected water saving, the duration of the restoration of Lake Karla to its original state before it was drained in the 1960s and the corresponding investment cost. The survey results show that socio-demographic factors and the average annual income influence the criteria and the views of farmers on a possible investment in the new method of automated drip irrigation. Moreover, there is a positive demand and willingness to pay for automated drip irrigation from the farmers in order to increase crop yield and speed up restoration of Lake Karla, considering that they are highly dependent on it.
NASA Astrophysics Data System (ADS)
Aouade, Ghizlane; Jarlan, Lionel; Ezzahar, Jamal; Er-raki, Salah; Napoly, Adrien; Benkaddour, Abdelfettah; Khabba, Said; Boulet, Gilles; Chehbouni, Abdelghani; Boone, Aaron
2016-04-01
The Haouz region, typical of southern Mediterranean basins, is characterized by a semi-arid climate, with average annual rainfall of 250, whilst evaporative demand is about 1600 mm per year. Under these conditions, crop irrigation is inevitable for growth and development. Irrigated agriculture currently consumes the majority of total available water (up to 85%), making it critical for more efficient water use. Flood irrigation is widely practiced by the majority of the farmers (more than 85 %) with an efficiency which does not exceed 50%. In this context, a good knowledge of the partitioning of evapotranspiration (ET) into soil evaporation and plant transpiration is of crucial need for improving the irrigation scheduling and thus water use efficiency. In this study, the ISBA (Interactions Soil-Biosphere-Atmosphere) model was used for estimating ET and its partition over an olive orchard and a wheat field located near to the Marrakech City (Centre of Morocco). Two versions were evaluated: standard version which simulates a single energy balance for the soil and vegetation and the recently developed multiple energy balance (MEB) version which solves a separate energy balance for each of the two sources. Eddy covariance system, which provides the sensible and latent heat fluxes and meteorological instruments were operated during years 2003-2004 for the Olive Orchard and during years 2013 for wheat. The transpiration component was measured using a Sap flow system during summer over the wheat crop and stable isotope samples were gathered over wheat. The comparison between ET estimated by ISBA model and that measured by the Eddy covariance system showed that MEB version yielded a remarkable improvement compared to the standard version. The root mean square error (RMSE) and the correlation coefficient (R²) were about 45wm-2 and 0.8 for MEB version. By contrast, for the standard version, the RMSE and R² were about 60wm-2 and 0.7, respectively. The result also showed that MEB version simulates more accurately the crop transpiration compared to the standard version. The RMSE and R² were about 0.79 mm and 0.67 for MEB and 1.37mm and 0.65 for standard version. An in-depth analysis of the results points out : (1) a deficiency of the standard version in simulating soil evaporation, in particular after an irrigation event, that directly impact the latent heat fluxes prediction because of two much energy reaching the soil and (2) a significant improvement of the surface temperature predictions with the double energy balance version; an interesting feature in the context of data assimilation; (3) a poor parameterization of the stomatal conductance in the A-gs photosynthetic module that is corrected thanks to a stochastic parameter identification approach. Results have direct implication for the prediction of evapotranspiration and its partition over irrigated crops in semi-arid areas of the South Mediterranean region.
NASA Astrophysics Data System (ADS)
Roy, A.; Inamdar, A. B.
2017-12-01
Major parts of Upper Godavari River Basin are intensely drought prone and climate vulnerable in Maharashtra State, India. The economy of the state depends on the agronomic productivity of this region. So, it is necessary to monitor and regulate the effects of climate change and anthropogenic activity on agricultural land in that region. This study investigates and maps the barren-lands and alteration of agricultural lands, their decadal deviations with the multi-temporal LANDSAT satellite images; and finally quantifies the agricultural adaptations. This work involves the utilization of remote sensing and GIS tools and modeling. First, climatic trend analysis is carried out with dataset obtained from India Meteorological Department. Then, multi-temporal LANDSAT images are classified (Level I, hybrid classification technique are followed) to determine the decadal Land Use Land Cover (LULC) changes and correlated with the agricultural water demand. Finally, various LANDSAT band analysis is conducted to determine irrigated and non-irrigated cropping area estimation and identifying the agricultural adaptations. The analysis of LANDSAT images shows that barren-lands are most increased class during the study period. The overall spatial extent of barren-lands are increased drastically during the study period. The geospatial study (class-to-class conversion study) shows that, most of the conversion of the barren-lands are from the agricultural land and reserve or open forests. The barren-lands are constantly increasing and the agricultural land is linearly decreasing. Hence, there is an inverse correlation between barren-lands and agricultural land. Moreover, there is a shift to non-irrigated and less water demanding crops, from more water demanding crops, which is a noticeable adaptation. The surface-water availability is highly dependent on rainfall and/or climatic conditions. It is changing either way in a random fashion based upon the quantity of rainfall occurred in near preceding years. The agricultural lands are densely replenished around the dams and natural water bodies which serve as the water supply stations for the irrigation purposes. Hence, the study shows there are alteration in LULC, agricultural practices and surface-water availability and expansion of barren-lands.
Pumpage data from irrigation wells in eastern Laramie County, Wyoming, and Kimball County, Nebraska
Avery, Charles
1983-01-01
Quantitative information concerning pumpage by irrigation wells is an integral component of the U.S. Geological Survey High Plains Regional Aquifer System Analysis. Thus, operation time, discharge rate, and irrigated acreage were measured at approximately 450 randomly selected irrigation wells within 10 areas of the High Plains during the 1980 irrigation season. The data were used to estimate the seasonal mean application of water to crops and to project total pumpage by irrigation wells in 1980 throughout the High Plains area. As part of the sampling effort, 50 irrigation wells were randomly chosen from the area of eastern Laramie County, Wyoming, and Kimball County, Nebraska. Required information was collected on only 40 of the wells. For these wells, the seasonal mean application of water on the irrigated land was 15.2 inches. For the major crop types, the seasonal mean application, in inches, were as follows: alfalfa, 19.8; corn, 15.4; potatoes, 13.8; beans, 12.8; and small grains 10.2. (USGS)
NASA Astrophysics Data System (ADS)
Kloss, Sebastian; Schuetze, Niels; Schmitz, Gerd H.
2010-05-01
The strong competition for fresh water in order to fulfill the increased demand for food worldwide has led to a renewed interest in techniques to improve water use efficiency (WUE) such as controlled deficit irrigation. Furthermore, as the implementation of crop models into complex decision support systems becomes more and more common, it is imperative to reliably predict the WUE as ratio of water consumption and yield. The objective of this paper is the assessment of the problems the crop models - such as FAO-33, DAISY, and APSIM in this study - face when maximizing the WUE. We applied these crop models for calculating the risk in yield reduction in view of different sources of uncertainty (e.g. climate) employing a stochastic framework for decision support for the planning of water supply in irrigation. The stochastic framework consists of: (i) a weather generator for simulating regional impacts of climate change; (ii) a new tailor-made evolutionary optimization algorithm for optimal irrigation scheduling with limited water supply; and (iii) the above mentioned models for simulating water transport and crop growth in a sound manner. The results present stochastic crop water production functions (SCWPF) for different crops which can be used as basic tools for assessing the impact of climate variability on the risk for the potential yield. Case studies from India, Oman, Malawi, and France are presented to assess the differences in modeling water stress and yield response for the different crop models.
Improving irrigation efficiency : the need for a relevant sequence of the management tools
NASA Astrophysics Data System (ADS)
Fayolle, Y.
2009-04-01
With 70 % of worldwide withdrawals, irrigation efficiency is a key issue in the overall problem of water resources. Management of water dedicated to agriculture should be improved to secure food production and save water to deal with increasing domestic and industrial demands. This paper is based on the results of a collaborative research project conducted in India with a local NGO (the Aga Khan Rural Support Programme, AKRSP(I)) during which GIS were tested. It is aimed at analyzing the efficiency of water usage in a water development programme conducted by the partner NGO in the semi-arid margins of Gujarat state. The analysis raises the question of the articulation of legal, institutional, economical, and technical tools to improve water efficiency. The NGO supervises the construction of surface water harvesting structures for irrigation purposes. Following a participatory approach, it creates and trains user groups to which the management of dams would then be devolved. User group membership depends on financial contribution to the building costs. A legal vacuum regarding surface water management combined with unequal investment capacities favor the concentration of water resources in the hands of a limited number of farmers. This causes low water use efficiency, irrigation choices being mostly oriented to high water consumptive crops and recipient farmers showing no interest in investing in water saving techniques. Our observations favor equality of access and paying more attention to the sequence in which management tools are articulated. On a national scale, as a prerequisite, water user rights as well as NGO's intervention legal framework should be clarified. On a project scale, before construction, information systems could help to identify all potential beneficiaries and optimize equality of access. It aims at reducing the volume of water per farmer to encourage them to irrigate low water consumptive crops and invest in water saving techniques. Depending on individual investment capacities, financial support could be proposed to favor investments in micro-irrigation devices. Finally, we suggest delaying the use of economic tools, giving up financial participation to the building costs (to limit their discriminating effect on user groups access), and limiting their applications to watering charges to cover maintenance expenses.
Modeling salt movement and halophytic crop growth on marginal lands with the APEX model
NASA Astrophysics Data System (ADS)
Goehring, N.; Saito, L.; Verburg, P.; Jeong, J.; Garrett, A.
2016-12-01
Saline soils negatively impact crop productivity in nearly 20% of irrigated agricultural lands worldwide. At these saline sites, cultivation of highly salt-tolerant plants, known as halophytes, may increase productivity compared to conventional salt-sensitive crops (i.e., glycophytes), thereby increasing the economic potential of marginal lands. Through a variety of mechanisms, halophytes are more effective than glycophytes at excluding, accumulating, and secreting salts from their tissues. Each mechanism can have a different impact on the salt balance in the plant-soil-water system. To date, little information is available to understand the long-term impacts of halophyte cultivation on environmental quality. This project utilizes the Agricultural Policy/Environmental Extender (APEX) model, developed by the US Department of Agriculture, to model the growth and production of two halophytic crops. The crops being modeled include quinoa (Chenopodium quinoa), which has utilities for human consumption and forage, and AC Saltlander green wheatgrass (Elymus hoffmannii), which has forage utility. APEX simulates salt movement between soil layers and accounts for the salt balance in the plant-soil-water system, including salinity in irrigation water and crop-specific salt uptake. Key crop growth parameters in APEX are derived from experimental growth data obtained under non-stressed conditions. Data from greenhouse and field experiments in which quinoa and AC Saltlander were grown under various soil salinity and irrigation salinity treatments are being used to parameterize, calibrate, and test the model. This presentation will discuss progress on crop parameterization and completed model runs under different salt-affected soil and irrigation conditions.
USDA-ARS?s Scientific Manuscript database
Agriculture is one of the most important sources of nutrient contamination, mainly inorganic nitrogen (N) fertilization of intensive crops, such as corn (Zea mays L). Proper irrigation and nutrient management can reduce nutrient leaching while maintaining crop yield, which is critical in enhancing t...
USDA-ARS?s Scientific Manuscript database
Crop growth simulation models can address a variety of agricultural problems, but their use to directly assist in-season irrigation management decisions is less common. Confidence in model reliability can be increased if models are shown to provide improved in-season management recommendations, whi...
USDA-ARS?s Scientific Manuscript database
Reduced input systems such as alternating wetting and drying (AWD) and furrow irrigation can potentially reduce water costs and limit the release of greenhouse gases in rice production, but also can introduce unwanted crop stresses that compromise crop yield and quality, as well as introducing compl...
USDA-ARS?s Scientific Manuscript database
This research analyzes two groundwater conservation policies in the Kansas High Plains located within the Ogallala aquifer: 1) cost-share assistance to increase irrigation efficiency; and 2) incentive payments to convert irrigated crop production to dryland crop production. To compare the cost-effec...
Soil Water Sensing-Focus on Variable Rate Irrigation
USDA-ARS?s Scientific Manuscript database
Irrigation scheduling using soil water sensors is an exercise in maintaining the water content of the crop root zone soil above a lower limit defined by the management allowed depletion (MAD) for that soil and crop, but not so wet that too much water is lost to deep percolation. The management allow...
Uncertainty analysis of an irrigation scheduling model for water management in crop production
USDA-ARS?s Scientific Manuscript database
Irrigation scheduling tools are critical to allow producers to manage water resources for crop production in an accurate and timely manner. To be useful, these tools need to be accurate, complete, and relatively reliable. The current work presents the uncertainty analysis and its results for the Mis...
USDA-ARS?s Scientific Manuscript database
An improved ant colony optimization (ACO) formulation for the allocation of crops and water to different irrigation areas is developed. The formulation enables dynamic adjustment of decision variable options and makes use of visibility factors (VFs, the domain knowledge that can be used to identify ...
USDA-ARS?s Scientific Manuscript database
Little information exists about sources and sinks of greenhouse gases (GHGs) affected by management practices to account for net emissions from agroecosystems. We evaluated the effects of irrigation, tillage, crop rotation, and N fertilization on net global warming potential (GWP) and greenhouse gas...
78 FR 13454 - Common Crop Insurance Regulations; Pecan Revenue Crop Insurance Provisions
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-28
... farming practices, as applicable, must be exhausted before any action against FCIC for judicial review may... irrigated, non-irrigated and organic farming practice are contained in section 34(c) of the Basic Provisions... the size of their farming operation. For instance, all producers are required to submit an application...
Adaptability and performance of short-season maize hybrids in the southern high plains
USDA-ARS?s Scientific Manuscript database
Drought incidences change with year and location, and are prevalent in the Southern High Plains where annual rainfall is low and highly variable and most maize and other crops are irrigated. The low rainfall and groundwater overuse are leading to shortages of water for crop irrigation in this regio...
Leaf temperature of maize and crop water stress index with variable irrigation and nitrogen supply
USDA-ARS?s Scientific Manuscript database
Water scarcity due to changing climate, population growth, and economic development is a major threat to the sustainability of irrigated agriculture in the Western United States and other regions around the world. Water stress indices based on crop canopy temperature can be useful for assessing plan...
Deficit irrigation strategies and their impact on yield and nutritional quality of pomegranate fruit
USDA-ARS?s Scientific Manuscript database
In arid regions of the world, farmers use deficit irrigation (DI) strategies to supply water at levels below full crop evapotranspiration throughout the growing season or at specific phenological stages. In water-sensitive regions, growing crops that are water stress-resistant and tolerant of arid e...
Impacts of climate change on cropping patterns in a tropical, sub-humid watershed
Zwart, Sander J.; Hein, Lars
2018-01-01
In recent decades, there have been substantial increases in crop production in sub-Saharan Africa (SSA) as a result of higher yields, increased cropping intensity, expansion of irrigated cropping systems, and rainfed cropland expansion. Yet, to date much of the research focus of the impact of climate change on crop production in the coming decades has been on crop yield responses. In this study, we analyse the impact of climate change on the potential for increasing rainfed cropping intensity through sequential cropping and irrigation expansion in central Benin. Our approach combines hydrological modelling and scenario analysis involving two Representative Concentration Pathways (RCPs), two water-use scenarios for the watershed based on the Shared Socioeconomic Pathways (SSPs), and environmental water requirements leading to sustained streamflow. Our analyses show that in Benin, warmer temperatures will severely limit crop production increases achieved through the expansion of sequential cropping. Depending on the climate change scenario, between 50% and 95% of cultivated areas that can currently support sequential cropping or will need to revert to single cropping. The results also show that the irrigation potential of the watershed will be at least halved by mid-century in all scenario combinations. Given the urgent need to increase crop production to meet the demands of a growing population in SSA, our study outlines challenges and the need for planned development that need to be overcome to improve food security in the coming decades. PMID:29513753
NASA Astrophysics Data System (ADS)
Fischer, M. L.; Billesbach, D. P.; Riley, W. J.; Berry, J. A.; Torn, M. S.
2004-12-01
Accurate prediction of the regional responses of carbon and water fluxes to changing climate, land use, and management requires models that are parameterized and tested against measurements made in multiple land cover types and over seasonal and inter-annual time scales. In particular, modelers predicting fluxes for un-irrigated agriculture are posed with the additional challenge of characterizing the onset and severity of water stress. We report results from three years of an ongoing series of measurement campaigns that quantify the spatial heterogeneity of land surface-atmosphere exchanges of carbon dioxide, water, and energy. Eddy covariance flux measurements were made in pastures and dominant crop types surrounding the US-DOE Atmospheric Radiation Measurement Program central facility near Lamont, Oklahoma (36.605 N, 97.485 W). Ancillary measurements included radiation budget, meteorology, soil moisture and temperature, leaf area index, plant biomass, and plant and soil carbon and nitrogen content. Within a given year, the dominant spatial variation in fluxes of carbon, water, and energy are caused by variations of land cover due to the distinct phenology of winter-spring (winter wheat) versus summer crops (e.g., pasture, sorghum, soybeans). Within crop and yearly variations were smaller. In 2002, variations in net ecosystem carbon exchange (NEE), for three closely spaced winter wheat fields was 10-20%. Variations between years for the same crop types were also large. Net primary production (NPP) of winter wheat in the spring of 2003 versus 2002 increased by a factor of two, while NEE increased by 35%. The large increase in production and NEE are positively correlated with precipitation, integrated over the previous summer-fall periods. We discuss the implications of these results by extracting and comparing factors relevant for parameterization of land surface models and by comparing crop yield with historic variations in yield at the landscape scale.
NASA Astrophysics Data System (ADS)
Nelson, K.; Burchfield, E. K.
2017-12-01
California's Central Valley region is one of the most productive agricultural systems on the planet. The high levels of agricultural production in this region require large amounts of fresh water for irrigation. However, the long-term availability of water required to sustain such levels of agricultural production has been questioned following the latest drought in California. In this study, we use Bayesian multilevel spatiotemporal modeling techniques to examine the influence of the institutional structure of surface water rights in the Central Valley on agricultural production during the recent drought. The R-INLA package is employed to account for spatial processes that have the potential to influence the effects of water right structures on crop productivity as well as on extent of cultivation. Model results suggest that seniority in surface water access significantly improves crop productivity on cultivated lands, but does not directly affect the ability to maintain cultivated extent. In addition, results suggest that areas with more junior surface water rights tend to reduce extent of cultivation, but maintain crop productivity, as cumulative drought stress increases.
NASA Astrophysics Data System (ADS)
Malek, Keyvan; Stöckle, Claudio; Chinnayakanahalli, Kiran; Nelson, Roger; Liu, Mingliang; Rajagopalan, Kirti; Barik, Muhammad; Adam, Jennifer C.
2017-08-01
Food supply is affected by a complex nexus of land, atmosphere, and human processes, including short- and long-term stressors (e.g., drought and climate change, respectively). A simulation platform that captures these complex elements can be used to inform policy and best management practices to promote sustainable agriculture. We have developed a tightly coupled framework using the macroscale variable infiltration capacity (VIC) hydrologic model and the CropSyst agricultural model. A mechanistic irrigation module was also developed for inclusion in this framework. Because VIC-CropSyst combines two widely used and mechanistic models (for crop phenology, growth, management, and macroscale hydrology), it can provide realistic and hydrologically consistent simulations of water availability, crop water requirements for irrigation, and agricultural productivity for both irrigated and dryland systems. This allows VIC-CropSyst to provide managers and decision makers with reliable information on regional water stresses and their impacts on food production. Additionally, VIC-CropSyst is being used in conjunction with socioeconomic models, river system models, and atmospheric models to simulate feedback processes between regional water availability, agricultural water management decisions, and land-atmosphere interactions. The performance of VIC-CropSyst was evaluated on both regional (over the US Pacific Northwest) and point scales. Point-scale evaluation involved using two flux tower sites located in agricultural fields in the US (Nebraska and Illinois). The agreement between recorded and simulated evapotranspiration (ET), applied irrigation water, soil moisture, leaf area index (LAI), and yield indicated that, although the model is intended to work on regional scales, it also captures field-scale processes in agricultural areas.
Satellite Estimation of Fractional Cover in Several California Specialty Crops
NASA Technical Reports Server (NTRS)
Johnson, Lee; Cahn, Michael; Rosevelt, Carolyn; Guzman, Alberto; Farrara, Barry; Melton, Forrest S.
2016-01-01
Past research in California and elsewhere has revealed strong relationships between satellite NDVI, photosynthetically active vegetation fraction (Fc), and crop evapotranspiration (ETc). Estimation of ETc can support efficiency of irrigation practice, which enhances water security and may mitigate nitrate leaching. The U.C. Cooperative Extension previously developed the CropManage (CM) web application for evaluation of crop water requirement and irrigation scheduling for several high-value specialty crops. CM currently uses empirical equations to predict daily Fc as a function of crop type, planting date and expected harvest date. The Fc prediction is transformed to fraction of reference ET and combined with reference data from the California Irrigation Management Information System to estimate daily ETc. In the current study, atmospherically-corrected Landsat NDVI data were compared with in-situ Fc estimates on several crops in the Salinas Valley during 2011-2014. The satellite data were observed on day of ground collection or were linearly interpolated across no more than an 8-day revisit period. Results will be presented for lettuce, spinach, celery, broccoli, cauliflower, cabbage, peppers, and strawberry. An application programming interface (API) allows CM and other clients to automatically retrieve NDVI and associated data from NASA's Satellite Irrigation Management Support (SIMS) web service. The SIMS API allows for queries both by individual points or user-defined polygons, and provides data for individual days or annual timeseries. Updates to the CM web app will convert these NDVI data to Fc on a crop-specific basis. The satellite observations are expected to play a support role in Salinas Valley, and may eventually serve as a primary data source as CM is extended to crop systems or regions where Fc is less predictable.
Satellite Estimation of Fractional Cover in Several California Specialty Crops
NASA Astrophysics Data System (ADS)
Johnson, L.; Cahn, M.; Rosevelt, C.; Guzman, A.; Lockhart, T.; Farrara, B.; Melton, F. S.
2016-12-01
Past research in California and elsewhere has revealed strong relationships between satellite NDVI, photosynthetically active vegetation fraction (Fc), and crop evapotranspiration (ETc). Estimation of ETc can support efficiency of irrigation practice, which enhances water security and may mitigate nitrate leaching. The U.C. Cooperative Extension previously developed the CropManage (CM) web application for evaluation of crop water requirement and irrigation scheduling for several high-value specialty crops. CM currently uses empirical equations to predict daily Fc as a function of crop type, planting date and expected harvest date. The Fc prediction is transformed to fraction of reference ET and combined with reference data from the California Irrigation Management Information System to estimate daily ETc. In the current study, atmospherically-corrected Landsat NDVI data were compared with in-situ Fc estimates on several crops in the Salinas Valley during 2011-2014. The satellite data were observed on day of ground collection or were linearly interpolated across no more than an 8-day revisit period. Results will be presented for lettuce, spinach, celery, broccoli, cauliflower, cabbage, peppers, and strawberry. An application programming interface (API) allows CM and other clients to automatically retrieve NDVI and associated data from NASA's Satellite Irrigation Management Support (SIMS) web service. The SIMS API allows for queries both by individual points or user-defined polygons, and provides data for individual days or annual timeseries. Updates to the CM web app will convert these NDVI data to Fc on a crop-specific basis. The satellite observations are expected to play a support role in Salinas Valley, and may eventually serve as a primary data source as CM is extended to crop systems or regions where Fc is less predictable.
Khalid, Sana; Shahid, Muhammad; Natasha; Sarwar, Tania; Shah, Ali Haidar
2018-01-01
Population densities and freshwater resources are not evenly distributed worldwide. This has forced farmers to use wastewater for the irrigation of food crops. This practice presents both positive and negative effects with respect to agricultural use, as well as in the context of environmental contamination and toxicology. Although wastewater is an important source of essential nutrients for plants, many environmental, sanitary, and health risks are also associated with the use of wastewater for crop irrigation due to the presence of toxic contaminants and microbes. This review highlights the harmful and beneficial impacts of wastewater irrigation on the physical, biological, and chemical properties of soil (pH, cations and anions, organic matter, microbial activity). We delineate the potentially toxic element (PTEs) build up in the soil and, as such, their transfer into plants and humans. The possible human health risks associated with the use of untreated wastewater for crop irrigation are also predicted and discussed. We compare the current condition of wastewater reuse in agriculture and the associated environmental and health issues between developing and developed countries. In addition, some integrated sustainable solutions and future perspectives are also proposed, keeping in view the regional and global context, as well as the grounded reality of wastewater use for crop production, sanitary and planning issues, remedial techniques, awareness among civil society, and the role of the government and the relevant stakeholders. PMID:29724015
Khalid, Sana; Shahid, Muhammad; Bibi, Irshad; Sarwar, Tania; Shah, Ali Haidar; Niazi, Nabeel Khan
2018-05-01
Population densities and freshwater resources are not evenly distributed worldwide. This has forced farmers to use wastewater for the irrigation of food crops. This practice presents both positive and negative effects with respect to agricultural use, as well as in the context of environmental contamination and toxicology. Although wastewater is an important source of essential nutrients for plants, many environmental, sanitary, and health risks are also associated with the use of wastewater for crop irrigation due to the presence of toxic contaminants and microbes. This review highlights the harmful and beneficial impacts of wastewater irrigation on the physical, biological, and chemical properties of soil (pH, cations and anions, organic matter, microbial activity). We delineate the potentially toxic element (PTEs) build up in the soil and, as such, their transfer into plants and humans. The possible human health risks associated with the use of untreated wastewater for crop irrigation are also predicted and discussed. We compare the current condition of wastewater reuse in agriculture and the associated environmental and health issues between developing and developed countries. In addition, some integrated sustainable solutions and future perspectives are also proposed, keeping in view the regional and global context, as well as the grounded reality of wastewater use for crop production, sanitary and planning issues, remedial techniques, awareness among civil society, and the role of the government and the relevant stakeholders.
Soil nitrogen balance under wastewater management: Field measurements and simulation results
Sophocleous, M.; Townsend, M.A.; Vocasek, F.; Ma, Liwang; KC, A.
2009-01-01
The use of treated wastewater for irrigation of crops could result in high nitrate-nitrogen (NO3-N) concentrations in the vadose zone and ground water. The goal of this 2-yr field-monitoring study in the deep silty clay loam soils south of Dodge City, Kansas, was to assess how and under what circumstances N from the secondary-treated, wastewater-irrigated corn reached the deep (20-45 m) water table of the underlying High Plains aquifer and what could be done to minimize this problem. We collected 15.2-m-deep soil cores for characterization of physical and chemical properties; installed neutron probe access tubes to measure soil-water content and suction lysimeters to sample soil water periodically; sampled monitoring, irrigation, and domestic wells in the area; and obtained climatic, crop, irrigation, and N application rate records for two wastewater-irrigated study sites. These data and additional information were used to run the Root Zone Water Quality Model to identify key parameters and processes that influence N losses in the study area. We demonstrated that NO3-N transport processes result in significant accumulations of N in the vadose zone and that NO3-N in the underlying ground water is increasing with time. Root Zone Water Quality Model simulations for two wastewater-irrigated study sites indicated that reducing levels of corn N fertilization by more than half to 170 kg ha-1 substantially increases N-use efficiency and achieves near-maximum crop yield. Combining such measures with a crop rotation that includes alfalfa should further reduce the accumulation and downward movement of NO3-N in the soil profile. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.
Connecting Groundwater, Crop Price, and Crop Production Variability in India
NASA Astrophysics Data System (ADS)
Pollack, A.; Lobell, D. B.; Jain, M.
2015-12-01
Farmers in India rely on groundwater resources for irrigation and production of staple crops that provide over half of the calories consumed domestically each year. While this has been a productive strategy in increasing agricultural production and maintaining high yields, groundwater resources are depleting at a quicker rate than natural resources can replace. This issue gains relevance as climate variability concurrently adds to yearly fluctuations in farmer demand for irrigation each year, which can create high risk for farmers that depend on consistent yields, but do not have access to dwindling water resources. This study investigates variability in groundwater levels from 2005 to 2013 in relation to crop prices and production by analyzing district-level datasets made available through India's government. Through this analysis, we show the impact of groundwater variability on price variability, crop yield, and production during these years. By examining this nine-year timescale, we extend our analysis to forthcoming years to demonstrate the increasing importance of groundwater resources in irrigation, and suggest strategies to reduce the impact of groundwater shortages on crop production and prices.
Airborne monitoring of crop canopy temperatures for irrigation scheduling and yield prediction
NASA Technical Reports Server (NTRS)
Millard, J. P.; Jackson, R. D.; Goettelman, R. C.; Reginato, R. J.; Idso, S. B.; Lapado, R. L.
1977-01-01
Airborne and ground measurements were made on April 1 and 29, 1976, over a USDA test site consisting mostly of wheat in various stages of water stress, but also including alfalfa and bare soil. These measurements were made to evaluate the feasibility of measuring crop temperatures from aircraft so that a parameter termed stress degree day, SDD, could be computed. Ground studies have shown that SDD is a valuable indicator of a crop's water needs, and that it can be related to irrigation scheduling and yield. The aircraft measurement program required predawn and afternoon flights coincident with minimum and maximum crop temperatures. Airborne measurements were made with an infrared line scanner and with color IR photography. The scanner data were registered, subtracted, and color-coded to yield pseudo-colored temperature-difference images. Pseudo-colored images reading directly in daily SDD increments were also produced. These maps enable a user to assess plant water status and thus determine irrigation needs and crop yield potentials.
Barbagallo, Salvatore; Consoli, Simona; Russo, Alfonso
2009-01-01
Daily evapotranspiration fluxes over the semi-arid Catania Plain area (Eastern Sicily, Italy) were evaluated using remotely sensed data from Landsat Thematic Mapper TM5 images. A one-source parameterization of the surface sensible heat flux exchange using satellite surface temperature has been used. The transfer of sensible and latent heat is described by aerodynamic resistance and surface resistance. Required model inputs are brightness, temperature, fractional vegetation cover or leaf area index, albedo, crop height, roughness lengths, net radiation, air temperature, air humidity and wind speed. The aerodynamic resistance (r(ah)) is formulated on the basis of the Monin-Obukhov surface layer similarity theory and the surface resistance (r(s)) is evaluated from the energy balance equation. The instantaneous surface flux values were converted into evaporative fraction (EF) over the heterogeneous land surface to derive daily evapotranspiration values. Remote sensing-based assessments of crop water stress (CWSI) were also made in order to identify local irrigation requirements. Evapotranspiration data and crop coefficient values obtained from the approach were compared with: (i) data from the semi-empirical approach "K(c) reflectance-based", which integrates satellite data in the visible and NIR regions of the electromagnetic spectrum with ground-based measurements and (ii) surface energy flux measurements collected from a micrometeorological tower located in the experiment area. The expected variability associated with ET flux measurements suggests that the approach-derived surface fluxes were in acceptable agreement with the observations.
Estimated water use in Puerto Rico, 2010
Molina-Rivera, Wanda L.
2014-01-01
Water-use data were aggregated for the 78 municipios of the Commonwealth of Puerto Rico for 2010. Five major offstream categories were considered: public-supply water withdrawals and deliveries, domestic and industrial self-supplied water use, crop-irrigation water use, and thermoelectric-power freshwater use. One instream water-use category also was compiled: power-generation instream water use (thermoelectric saline withdrawals and hydroelectric power). Freshwater withdrawals for offstream use from surface-water [606 million gallons per day (Mgal/d)] and groundwater (118 Mgal/d) sources in Puerto Rico were estimated at 724 million gallons per day. The largest amount of freshwater withdrawn was by public-supply water facilities estimated at 677 Mgal/d. Public-supply domestic water use was estimated at 206 Mgal/d. Fresh groundwater withdrawals by domestic self-supplied users were estimated at 2.41 Mgal/d. Industrial self-supplied withdrawals were estimated at 4.30 Mgal/d. Withdrawals for crop irrigation purposes were estimated at 38.2 Mgal/d, or approximately 5 percent of all offstream freshwater withdrawals. Instream freshwater withdrawals by hydroelectric facilities were estimated at 556 Mgal/d and saline instream surface-water withdrawals for cooling purposes by thermoelectric-power facilities was estimated at 2,262 Mgal/d.
Decadal reduction of Chinese agriculture after a regional nuclear war
NASA Astrophysics Data System (ADS)
Xia, Lili; Robock, Alan; Mills, Michael; Stenke, Andrea; Helfand, Ira
2015-02-01
A regional nuclear war between India and Pakistan could decrease global surface temperature by 1°C-2°C for 5-10 years and have major impacts on precipitation and solar radiation reaching Earth's surface. Using a crop simulation model forced by three global climate model simulations, we investigate the impacts on agricultural production in China, the largest grain producer in the world. In the first year after the regional nuclear war, a cooler, drier, and darker environment would reduce annual rice production by 30 megaton (Mt) (29%), maize production by 36 Mt (20%), and wheat production by 23 Mt (53%). With different agriculture management—no irrigation, auto irrigation, 200 kg/ha nitrogen fertilizer, and 10 days delayed planting date—simulated national crop production reduces 16%-26% for rice, 9%-20% for maize, and 32%-43% for wheat during 5 years after the nuclear war event. This reduction of food availability would continue, with gradually decreasing amplitude, for more than a decade. Assuming these impacts are indicative of those in other major grain producers, a nuclear war using much less than 1% of the current global arsenal could produce a global food crisis and put a billion people at risk of famine.
Food security, irrigation, climate change, and water scarcity in India
NASA Astrophysics Data System (ADS)
Hertel, T. W.; Taheripour, F.; Gopalakrishnan, B. N.; Sahin, S.; Escurra, J.
2015-12-01
This paper uses an advanced CGE model (Taheripour et al., 2013) coupled with hydrological projections of future water scarcity and biophysical data on likely crop yields under climate change to examine how water scarcity, climate change, and trade jointly alter land use changes across the Indian subcontinent. Climate shocks to rainfed and irrigated yields in 2030 are based on the p-DSSAT crop model, RCP 2.6, as reported under the AgMIP project (Rosenzweig et al., 2013), accessed through GEOSHARE (Villoria et al, 2014). Results show that, when water scarcity is ignored, irrigated areas grow in the wake of climate change as the returns to irrigation rise faster than for rainfed uses of land within a given agro-ecological zone. When non-agricultural competition for future water use, as well as anticipated supply side limitations are brought into play (Rosegrant et al., 2013), the opportunity cost of water rises across all river basins, with the increase ranging from 12% (Luni) to 44% (Brahmaputra). As a consequence, irrigated crop production is curtailed in most regions (Figure 1), with the largest reductions coming in the most water intensive crops, namely rice and wheat. By reducing irrigated area, which tends to have much higher yields, the combined effects of water scarcity and climate impacts require an increase in total cropped area, which rises by about 240,000 ha. The majority of this area expansion occurs in the Ganges, Indus, and Brahmari river basins. Overall crop output falls by about 2 billion, relative to the 2030 baseline, with imports rising by about 570 million. The combined effects of climate change and water scarcity for irrigation also have macro-economic consequences, resulting in a 0.28% reduction in GDP and an increase in the consumer price index by about 0.4% in 2030, compared the baseline. The national welfare impact on India amounts to roughly 3 billion (at 2007 prices) in 2030. Assuming a 3% social discount rate, the net present value of the annual reductions in welfare will be about 24.3 billion for 2008 to 2030. This study highlights the importance of considering the interplay between climate and water availability in assessments of food security.
Agricultural practices and irrigation water demand in Uttar Pradesh
NASA Astrophysics Data System (ADS)
O'Keeffe, J.; Buytaert, W.; Brozovic, N.; Mijic, A.
2013-12-01
Changes in farming practices within Uttar Pradesh, particularly advances in irrigation technology, have led to a significant drop in water tables across the region. While the acquisition of monitoring data in India is a challenge, current water use practices point towards water overdraught. This is exacerbated by government and state policies and practices, including the subsidising of electricity, seeds and fertilizer, and an agreement to buy all crops grown, promoting the over use of water resources. Taking India's predicted population growth, increases in industrialisation and climate change into account, both farmland and the water resources it depends upon will be subject to increased pressures in the future. This research is centred around irrigation demands on water resources within Uttar Pradesh, and in particular, quantifying those demands both spatially and temporally. Two aspects of this will be presented; the quantification of irrigation water applied and the characterisation of the spatial heterogeneity of water use practices. Calculating the volumes of applied irrigation water in the absence of observed data presents a major challenge and is achieved here through the use of crop models. Regional crop yields provided by statistical yearbooks are replicated by the crop models AquaCrop and InfoCrop, and by doing so the amount of irrigation water needed to produce the published yields is quantified. In addition, proxy information, for example electrical consumption for agricultural use, is used to verify the likely volumes of water abstracted from tubewells. Statistical analyses of borehole distribution and the characterisation of the spatial heterogeneity of water use practices, particularly farmer decision making, collected during a field trip are also presented. The evolution of agricultural practices, technological advancement and water use for irrigation is reconstructed through the use of multiple regression and principle component analysis, allowing the identification of drivers of current water use practices. The importance of undertaking this research to model set up and for the advancement of overall understanding of the hydrological system is emphasised along with its significance in developing policy and informing water allocation models; a platform for more sustainable future water resource management in the region.
Effect of irrigation and winery waste compost rates in nitrate leaching in vulnerable zones
NASA Astrophysics Data System (ADS)
Requejo, Maria Isabel; Castellanos, Maria Teresa; Villena, Raquel; Ribas, Francisco; Jesús Cabello, Maria; Arce, Augusto; Cartagena, Maria Carmen
2013-04-01
The winery industry is widespread in Spain (3,610,000 tonnes of wine in 2010 (FAO, 2010)), and generates wastes characterized by a high content of organic matter, a notable content in macronutrients and low heavy-metals. These organic wastes could be used for agricultural purposes after a correct stabilization process (e.g. composting).The addition of these organic wastes requires a correct management, especially on semiarid cropped areas of central Spain where environmental degradation of water supplies with high N loads is observed. An integrated optimization of both applied compost dose and amount of irrigation is important to ensure optimum yields and minimum nitrate leaching losses. The purpose of this work was to study the effect of the application of winery waste compost as fertilizer in a melon crop cultivated with different drip irrigation rates. The field experiment was carried out in Ciudad Real, designated "vulnerable zone" by the "Nitrates Directive" 91/676/CEE. Melon crop has been traditionally cultivated in this area with high inputs of water and fertilizers, but no antecedents of application of winery wastes are known. Beside the control treatment (D0), three doses of compost were applied: 6.7 (D1), 13.3 (D2) and 20 T/ha(D3).Irrigation treatments consisted of applying a 100% ETc and an excess irrigation of 120% ETc. The soil was a shallow sandy-loam (Petrocalcic Palexeralfs), with 0.6 m depth and a discontinuous petrocalcic horizon between 0.6 and 0.7 m. Drainage and nitrate concentration on the soil solution were measured weekly to determine N leached during the crop period. Crop yield was also followed by harvesting plots when a significant number of fruits were fully matured. A comparison between nitrate leached and crop production among different treatments and irrigation rates are presented. Acknowledgements: This project has been supported by INIA-RTA2010-00110-C03-01.
Evaluation of the Community Land Model (CLM-Crop) in the United States Corn Belt
NASA Astrophysics Data System (ADS)
Chen, M.; Griffis, T.
2013-12-01
An accurate representation of crop phenology in land surface models is crucial for predicting the carbon, water and energy budgets of managed ecosystems. Soybean and corn are cultivated in approximately 600,000 km2 in the Corn Belt- an area greater than the entire State of California. Accurate prediction of the radiation, energy, and carbon budgets of this region is especially important for understanding its influence on radiative forcing, the thermodynamic properties of the atmospheric boundary layer, and changes in climate. Recently, key algorithms describing crop biophysics and interactive crop management (planting, fertilization, irrigation, harvesting) have been implemented in the Community Land Model (CLM-Crop). CLM-Crop provides a framework for prognostic simulation of crop phenology and evaluation of human management decisions under future climate scenarios. However, there is an important need to evaluate CLM-Crop against a broad range of agricultural site observations in order to understand its limitations and to help optimize the crop biophysical parameterization. Here we evaluated CLM-Crop version 4.5 at 9 AmeriFlux corn/soybean sites that are located within the United States Corn Belt. The following questions were addressed: 1) How well does CLM perform for the 9 crop sites with different management techniques (e.g., tillage vs. no-till, rainfed vs. irrigated)? 2) What are the model's strengths and weaknesses of simulating crop phenology, energy fluxes and carbon fluxes? 3) What steps are needed in order to improve the reliability of the CLM-Crop simulations? Our preliminary results indicate that CLM-Crop can simulate the radiation, energy, and carbon fluxes with reasonable accuracy during the mid growing season. The model performance degrades substantially during the early and late growing seasons, which we attribute to a bias in crop phenology. For instance, we observed that the simulated corn and soybean phenology (LAI) has an earlier phase than the observations by about 15 days at many sites. Here, we show how the optimization of carbon allocation and crop phenology influences the modeled radiation, energy, and carbon fluxes and discuss other model deficiencies associated with the crop biophysics scheme.
Automated irrigation management with soil and canopy sensing
USDA-ARS?s Scientific Manuscript database
Automated irrigation management provides for real time feedback between crop water needs and the delivery of specific amount of irrigation water to specific locations on demand. In addition to the basic components of any irrigation system, e.g. pumps, filters, valves, pipes and tubing, sprinkler he...
Water-use trends in the desert southwest--1950-2000
Konieczki, Alice D.; Heilman, Julie A.
2004-01-01
The population of the Desert Southwest is among the fastest growing in the country. In this area, ground-water supplies have been developed, surface-water resources have been fully appropriated, and conservation and conjunctive water-use measures are being used to meet water-resource needs. Complex networks of water-distribution systems have been developed to deliver surface-water supplies, and interstate agreements, such as the Colorado River Compact of 1922, help manage the distribution of water among many States in the Western United States, including Arizona, California, Nevada, New Mexico, and Utah. The Colorado River, which lies on the borders of Arizona, California, and Nevada, plays an important role in supplying water to the Southwest. Water from the Colorado River is used to irrigate extensive farmland in the southern California deserts and is delivered to southern and central Arizona through the Central Arizona Project canal for domestic and agricultural uses. It is also the source of much of the water used for domestic purposes in southern Nevada. Estimated water-withdrawal and related data were compiled from various sources to identify trends in Arizona, California, Nevada, New Mexico, and Utah. More water is used for agriculture than domestic and industrial use in these five States. From 1950 to 2000, however, the percentage increase in withdrawal for domestic water use exceeded that for agricultural use. The estimated amount of water withdrawn for domestic, agricultural, and industrial purposes in Arizona, California, Nevada, New Mexico, and Utah increased 58 percent, from 39.6 to 62.8 million acre-feet, from 1950 to 2000. During this period withdrawals for domestic water use, which included self-supplied domestic and public supply (all deliveries to residential, commercial, and some industrial users), increased 410 percent from 2.0 million to 10.2 million acre-feet and the population in these five Southwestern States increased 250 percent. From 1965 to 2000, water withdrawals for agriculture, which were primarily for irrigation of crops and livestock uses, increased 14 percent in the five States, from 44.0 to 50.2 million acre-feet, while irrigated acreage increased 12 percent from 12.6 to 14.1 million acres. Water-use trends in the Southwest are dominated by water use in California where crop acreage is more than twice as large as the combined crop acreages in Arizona, Nevada, New Mexico, and Utah, and the population in 2000 was more than three times larger than the combined population of these States. Withdrawals for agriculture in California accounted for 62 percent of the water withdrawals for agriculture in the five States in 1950 and 68 percent in 2000. Water withdrawals for domestic-water use in California declined from 82 percent of the total domestic-water withdrawals in all five States in 1950 to 70 percent in 2000, indicating that the need for domestic withdrawals increased more in Arizona, Nevada, New Mexico, and Utah combined than in California. The population of California is larger than the combined population of Arizona, New Mexico, Nevada, and Utah, but the combined population of these smaller States grew faster than the population of California. From 1950 to 2000 the California population increased 220 percent, but the combined population of the four other States increased 390 percent. From 1960 to 2000, public supply per-capita use increased in Arizona, New Mexico, and California, and decreased in Nevada and Utah. Crop-application rates (water withdrawal for irrigation of crops divided by the irrigated crop acreage) from 1965 to 2000 ranged from 2.32 acre-feet per acre in Utah in 1975 to 6.21 acre-feet per acre in Arizona in 2000. More water is used per acre of irrigated land in Arizona than in the other four States. This could be due to several reasons, including differences in climate, conveyance losses, length of growing season, and type of crops grown. Trends in water
NASA Astrophysics Data System (ADS)
Jiang, Y.; Huang, G., Sr.; Xu, X.; Huang, Q.; Huo, Z.
2015-12-01
Severe water scarcity and unreasonable allocation are threatening the eco-environment in the Heihe River basin (HRB), an arid and semi-arid watershed in Northwest China. The water use in the middle oasis accounts for about 70% of the total water use in the HRB, in which over 85% are consumed by irrigated agriculture. Thus the regional assessment and improvement of irrigation water use are quite essential for water-saving and eco-environmental sustainability. This paper applied a distributed agro-hydrological model (SWAP-EPIC) integrated with ArcGIS to investigate the irrigation water use efficiency (WUE) in the middle oasis. The detailed distributed data in 2012, including soil properties, irrigation schedules, crop pattern and calendar, were collected and used in the regional simulation. The spatial-temporal distribution of LAI and evapotranspiration (ETa) from remote sensing were used as observations to calibrate the model. Results showed that the simulation data was in a good agreement with the observation one. The relative WUE (i.e. divided by the mean value) ranged from 0.77 to 1.33 in different canal command areas. Large spatial variations of WUE were mainly caused by the non-uniform distribution of irrigation water. The present irrigation performance was poor, and only 50% of total irrigation amount was finally utilized through evapotranspiration in the whole district. While nearly 24% of the irrigation water were lost through field deep percolation and 26% were wasted in canal conveyance. Further analysis of water-saving scenarios was conducted through applying the improved irrigation schedule for each crop-soil unites and increasing the canal conveyance efficiency. Prediction showed that 15% of total irrigation amount can be saved without reduction of crop yield.
USDA-ARS?s Scientific Manuscript database
Many of the irrigation systems today in the U.S. Central Great Plains no longer have the capacity to match peak irrigation needs during the summer and must rely on soil water reserves to buffer the crop from water stress. Considerable research was conducted on preseason irrigation in the U.S. Great ...
NASA Astrophysics Data System (ADS)
Quiroga, S.; Fernández-Haddad, Z.; Iglesias, A.
2011-02-01
The increasing pressure on water systems in the Mediterranean enhances existing water conflicts and threatens water supply for agriculture. In this context, one of the main priorities for agricultural research and public policy is the adaptation of crop yields to water pressures. This paper focuses on the evaluation of hydrological risk and water policy implications for food production. Our methodological approach includes four steps. For the first step, we estimate the impacts of rainfall and irrigation water on crop yields. However, this study is not limited to general crop production functions since it also considers the linkages between those economic and biophysical aspects which may have an important effect on crop productivity. We use statistical models of yield response to address how hydrological variables affect the yield of the main Mediterranean crops in the Ebro river basin. In the second step, this study takes into consideration the effects of those interactions and analyzes gross value added sensitivity to crop production changes. We then use Montecarlo simulations to characterize crop yield risk to water variability. Finally we evaluate some policy scenarios with irrigated area adjustments that could cope in a context of increased water scarcity. A substantial decrease in irrigated land, of up to 30% of total, results in only moderate losses of crop productivity. The response is crop and region specific and may serve to prioritise adaptation strategies.
Risk of water scarcity and water policy implications for crop production in the Ebro Basin in Spain
NASA Astrophysics Data System (ADS)
Quiroga, S.; Fernández-Haddad, Z.; Iglesias, A.
2010-08-01
The increasing pressure on water systems in the Mediterranean enhances existing water conflicts and threatens water supply for agriculture. In this context, one of the main priorities for agricultural research and public policy is the adaptation of crop yields to water pressures. This paper focuses on the evaluation of hydrological risk and water policy implications for food production. Our methodological approach includes four steps. For the first step, we estimate the impacts of rainfall and irrigation water on crop yields. However, this study is not limited to general crop production functions since it also considers the linkages between those economic and biophysical aspects which may have an important effect on crop productivity. We use statistical models of yield response to address how hydrological variables affect the yield of the main Mediterranean crops in the Ebro River Basin. In the second step, this study takes into consideration the effects of those interactions and analyzes gross value added sensitivity to crop production changes. We then use Montecarlo simulations to characterize crop yield risk to water variability. Finally we evaluate some policy scenarios with irrigated area adjustments that could cope in a context of increased water scarcity. A substantial decrease in irrigated land, of up to 30% of total, results in only moderate losses of crop productivity. The response is crop and region specific and may serve to prioritise adaptation strategies.
Simón, Luis; Afonin, Alexandr; López-Díez, Lucía Isabel; González-Miguel, Javier; Morchón, Rodrigo; Carretón, Elena; Montoya-Alonso, José Alberto; Kartashev, Vladimir; Simón, Fernando
2014-03-01
Zoonotic filarioses caused by Dirofilaria immitis and Dirofilaria repens are transmitted by culicid mosquitoes. Therefore Dirofilaria transmission depends on climatic factors like temperature and humidity. In spite of the dry climate of most of the Spanish territory, there are extensive irrigated crops areas providing moist habitats favourable for mosquito breeding. A GIS model to predict the risk of Dirofilaria transmission in Spain, based on temperatures and rainfall data as well as in the distribution of irrigated crops areas, is constructed. The model predicts that potential risk of Dirofilaria transmission exists in all the Spanish territory. Highest transmission risk exists in several areas of Andalucía, Extremadura, Castilla-La Mancha, Murcia, Valencia, Aragón and Cataluña, where moderate/high temperatures coincide with extensive irrigated crops. High risk in Balearic Islands and in some points of Canary Islands, is also predicted. The lowest risk is predicted in Northern cold and scarcely or non-irrigated dry Southeastern areas. The existence of irrigations locally increases transmission risk in low rainfall areas of the Spanish territory. The model can contribute to implement rational preventive therapy guidelines in accordance with the transmission characteristics of each local area. Moreover, the use of humidity-related factors could be of interest in future predictions to be performed in countries with similar environmental characteristics. Copyright © 2014 Elsevier B.V. All rights reserved.
Hu, Tiantian; Kang, Shaozhong; Li, Fusheng; Zhang, Jianhua
2011-01-01
Effects of partial root-zone irrigation (PRI) on the hydraulic conductivity in the soil–root system (Lsr) in different root zones were investigated using a pot experiment. Maize plants were raised in split-root containers and irrigated on both halves of the container (conventional irrigation, CI), on one side only (fixed PRI, FPRI), or alternately on one of two sides (alternate PRI, APRI). Results show that crop water consumption was significantly correlated with Lsr in both the whole and irrigated root zones for all three irrigation methods but not with Lsr in the non-irrigated root zone of FPRI. The total Lsr in the irrigated root zone of two PRIs was increased by 49.0–92.0% compared with that in a half root zone of CI, suggesting that PRI has a significant compensatory effect of root water uptake. For CI, the contribution of Lsr in a half root zone to Lsr in the whole root zone was ∼50%. For FPRI, the Lsr in the irrigated root zone was close to that of the whole root zone. As for APRI, the Lsr in the irrigated root zone was greater than that of the non-irrigated root zone. In comparison, the Lsr in the non-irrigated root zone of APRI was much higher than that in the dried zone of FPRI. The Lsr in both the whole and irrigated root zones was linearly correlated with soil moisture in the irrigated root zone for all three irrigation methods. For the two PRI treatments, total water uptake by plants was largely determined by the soil water in the irrigated root zone. Nevertheless, the non-irrigated root zone under APRI also contributed to part of the total crop water uptake, but the continuously non-irrigated root zone under FPRI gradually ceased to contribute to crop water uptake, suggesting that it is the APRI that can make use of all the root system for water uptake, resulting in higher water use efficiency. PMID:21527627
NASA Astrophysics Data System (ADS)
Sharma, S.
2012-12-01
Accurate estimation of water content in the crop root zone is most important for water conservation and management practices like irrigation. The objective of this study is to use the FA0-56 dual crop cefficients: basal crop coefficient Kcb and the soil evaporation coefficient Ke for a large corn/soybean field in the year 2005 at the Mead Turf Farm in the state of Nebraska, USA..Dual crop coefficients can be used to estimate both transpiration from crops and evaporation from soil. The Kcb has a low value of 0.15(K cb, in) during the initial period, increases rapidly to a maximum of 1.14 (K cb, mid) for the entire midseason and decreases rapidly to 0.5 at the end of the corn growing season (K cb,end). When examined together with precipitation, the dual crop coefficient was higher following rainfall or irrigation, as expected. The data suggests that the dual crop coefficient approach is a good estimation of water loss from well-watered crops. Irrigation can be scheduled to replace the loss of water from the crop/soil system. Similarly, when we compared the measured daily ET and the ET calculated from dual crop coefficients, it gives 98 % R2.; Comparision of calculated ET from dual crop coefficient appraoch with Weather Station ET
NASA Astrophysics Data System (ADS)
Rodriguez-Sinobas, Leonor; Amado Mendoza Hidalgo, Edwin
2017-04-01
Within a water scarcity scenario, the irrigated agriculture economic sector would be affected by the reduction on water supply and this might have a negative impact on the National gross income. Water for irrigation in Spain comprises the 75% of total consumption. Therefore, the search for irrigation strategies dealing with sustainable irrigation by saving water and improving the environment quality is encouraged. Within this framework the assessment of water use in the irrigation districts to assist water stakeholder decisions is reinforced. Water resources can be assessed at field scheme or regional scale by analyzing the water use efficiency and the water productivity indicators. Which determine the water availability and the water supply quality in irrigation areas. Among then, the following are broadly used: water productivity WP, and irrigation water productivity IWP, annual relative water supply (ARWS) and the annual relative irrigation water supply (ARIS). Keeping in mind the water scarcity scenario for irrigation in the short and long term and the probably scenario of water allocation for different uses following criteria of efficiency and productivity, this work is aimed at assessing the water use efficiency and water productivity of two modernized Spanish irrigation districts CCRRs: "Canal Toro-Zamora" and "Canal Villagonzalo" from the Duero basin. For that purpose, the above indicators were estimated for years 2014 and 2015. Crop water requirements are needed to calculate the indicators. For this study, maize was chosen since it is the major crop in the area and its water needs were estimated with the FAO program Cropwat. Local crop coefficients (Kc) were determined with the open access application SpiderWebGis (http://maps.spiderwebgis.org/webgis/) which uses satelital images to monitor Kc coefficients in all crops across Spain. In both CCRRs the maize Kc coefficients were similar for all the phenology stages although a slightly spatial variability was observed. Likewise, water use efficiency was good (ARIS = 1) and the other indicators behave reasonably highlighting a good irrigation management. Thus, these indicators, and the methodology proposed to estimate kc, could assist water stakeholder decisions for water management strategies at the irrigation district. Moreover, the results could be references for benchmarking at regional, national or international level.
Pricing irrigation water for drought adaptation in Iran
NASA Astrophysics Data System (ADS)
Nikouei, Alireza; Ward, Frank A.
2013-10-01
This paper examines alternative water pricing arrangements that better manage and more accurately reflect conditions of increased water scarcity experienced during drought in Iran. A comprehensive water balance and crop use model compares the existing below cost water pricing model with an alternative two-tiered pricing approach. The tiers reflect two uses of irrigation water. The uses are (1) subsistence level crop production from farm household production of crops for food security and (2) discretionary cropping. Results of the study offer evidence for a reform of Iranian water pricing principles, subject to caveats described by the authors.
NASA Astrophysics Data System (ADS)
Lüneberg, Kathia; Schneider, Dominik; Daniel, Rolf; Siebe, Christina
2017-04-01
Soil bacteria are important determinants of soil fertility and ecosystem services as they participate in all biogeochemical cycles. Until now the comprehension of compositional and functional response that bacterial communities have to land use change and management, specifically in dry land its limited. Dry lands cover 40% of the world's land surface and its crop production supports one third of the global population. In this regions soil moisture is limited constraining farming to the rainy season or oblige to irrigate, as fresh water resources become scarce, to maintain productivity, treated or untreated wastewater for field irrigation is used. In this study the transformation of semiarid shrubland to agriculture under different land systems regarding quantity and quality of water use for crop irrigation on bacterial communities was investigated. The land systems included maize rain-fed plantations and irrigation systems with freshwater, untreated wastewater stored in a dam and untreated wastewater during dry and rainy season. Bacterial community structure and function was heavily affected by land use system and soil properties, whereas seasonality had a slighter effect. A soil moisture, nutrient and contaminant-content increasing gradient among the land use systems, going from rain fed plantation over fresh water, dam wastewater to untreated wastewater irrigated plantations was detected, this gradient diminished the abundance of Actinobacteria and Cyanobacteria, but enhanced the one from Bacteroidetes and Proteobacteria. Discernible clustering of the dry land soil communities coincides with the moisture, nutrient and contaminant gradient, being shrubland soil communities closer to the rain-fed's system and farer to the one from untreated wastewater irrigated soil. Soil moisture together with sodium content and pH were the strongest drivers of the community structure. Seasonality promoted shifts in the composition of soil bacteria under irrigation with freshwater and untreated wastewater, as these systems showed differences in soil properties between seasons such as P content and electric conductivity. Potential functional profiles revealed that differences in land use systems also influence distinct functional pathways. Nitrogen fixation, nitrification, denitrification pathways and methane metabolism are potentially enhanced in wastewater irrigation systems, while dissimilatory nitrate reduction, anammox, lignin and chitin degradation are diminished. The junction of 16S rRNA data and associated functional profiles provided extensive understanding into the bacterial community responses to changing environmental conditions associated with differences in land use, management and seasonality in drylands. Irrigation with wastewater can be potentially harmful as higher abundance of the pathogens A. baumanni, A. soli, A. junii, A. haemolyticus, A. schindleri, B. thuringiensis/anthracis,cereus and N. flavorosea was recorded in these systems.
Mapping irrigated areas in Afghanistan over the past decade using MODIS NDVI
Pervez, Md Shahriar; Budde, Michael; Rowland, James
2014-01-01
Agricultural production capacity contributes to food security in Afghanistan and is largely dependent on irrigated farming, mostly utilizing surface water fed by snowmelt. Because of the high contribution of irrigated crops (> 80%) to total agricultural production, knowing the spatial distribution and year-to-year variability in irrigated areas is imperative to monitoring food security for the country. We used 16-day composites of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to create 23-point time series for each year from 2000 through 2013. Seasonal peak values and time series were used in a threshold-dependent decision tree algorithm to map irrigated areas in Afghanistan for the last 14 years. In the absence of ground reference irrigated area information, we evaluated these maps with the irrigated areas classified from multiple snapshots of the landscape during the growing season from Landsat 5 optical and thermal sensor images. We were able to identify irrigated areas using Landsat imagery by selecting as irrigated those areas with Landsat-derived NDVI greater than 0.30–0.45, depending on the date of the Landsat image and surface temperature less than or equal to 310 Kelvin (36.9 ° C). Due to the availability of Landsat images, we were able to compare with the MODIS-derived maps for four years: 2000, 2009, 2010, and 2011. The irrigated areas derived from Landsat agreed well r2 = 0.91 with the irrigated areas derived from MODIS, providing confidence in the MODIS NDVI threshold approach. The maps portrayed a highly dynamic irrigated agriculture practice in Afghanistan, where the amount of irrigated area was largely determined by the availability of surface water, especially snowmelt, and varied by as much as 30% between water surplus and water deficit years. During the past 14 years, 2001, 2004, and 2008 showed the lowest levels of irrigated area (~ 1.5 million hectares), attesting to the severe drought conditions in those years, whereas 2009, 2012 and 2013 registered the largest irrigated area (~ 2.5 million hectares) due to record snowpack and snowmelt in the region. The model holds promise the ability to provide near-real-time (by the end of the growing seasons) estimates of irrigated area, which are beneficial for food security monitoring as well as subsequent decision making for the country. While the model is developed for Afghanistan, it can be adopted with appropriate adjustments in the derived threshold values to map irrigated areas elsewhere.
Water and Land Limitations to Future Agricultural Production in the Middle East
NASA Astrophysics Data System (ADS)
Koch, J. A. M.; Wimmer, F.; Schaldach, R.
2015-12-01
Countries in the Middle East use a large fraction of their scarce water resources to produce cash crops, such as fruit and vegetables, for international markets. At the same time, these countries import large amounts of staple crops, such as cereals, required to meet the nutritional demand of their populations. This makes food security in the Middle East heavily dependent on world market prices for staple crops. Under these preconditions, increasing food demand due to population growth, urban expansion on fertile farmlands, and detrimental effects of a changing climate on the production of agricultural commodities present major challenges to countries in the Middle East that try to improve food security by increasing their self-sufficiency rate of staple crops.We applied the spatio-temporal land-use change model LandSHIFT.JR to simulate how an expansion of urban areas may affect the production of agricultural commodities in Jordan. We furthermore evaluated how climate change and changes in socio-economic conditions may influence crop production. The focus of our analysis was on potential future irrigated and rainfed production (crop yield and area demand) of fruit, vegetables, and cereals. Our simulation results show that the expansion of urban areas and the resulting displacement of agricultural areas does result in a slight decrease in crop yields. This leads to almost no additional irrigation water requirements due to the relocation of agricultural areas, i.e. there is the same amount of "crop per drop". However, taking into account projected changes in socio-economic conditions and climate conditions, a large volume of water would be required for cereal production in order to safeguard current self-sufficiency rates for staple crops. Irrigation water requirements are expected to double until 2025 and to triple until 2050. Irrigated crop yields are projected to decrease by about 25%, whereas there is no decrease in rainfed crop yields to be expected.
Tracking antibiotic resistance genes in soil irrigated with dairy wastewater
USDA-ARS?s Scientific Manuscript database
In southern Idaho, the application of dairy wastewater to agricultural soils is a widely used practice to irrigate crops and recycle nutrients. In this study, small-scale field plots were irrigated monthly (6 times) with dairy wastewater (100%), wastewater diluted to 50% with irrigation (canal) wate...
Using Computer Models to Explore Alternative Scenarios for Managing Limited Irrigation Water
USDA-ARS?s Scientific Manuscript database
Crop water stress due to low precipitation and high temperatures are the main limiting factors for agricultural production in the Great Plains. Corn is grown under either rainfed or irrigated regimes. Irrigation can improve corn profitability in this region, but over-irrigation accelerates depletio...
USDA-ARS?s Scientific Manuscript database
Water availability for irrigated agriculture is declining in both China and the United States due to increased use for power generation, municipalities, industries and environmental protection. Persistent droughts have exacerbated the situation, leading to increases in irrigated area as farmers atte...
Reducing water inputs with subsurface drip irrigation may improve alfalfa nutritive value
USDA-ARS?s Scientific Manuscript database
Irrigated alfalfa (Medicago sativa L.) is an important forage crop for western Kansas dairy producers. Concerns over decreasing groundwater supplies have prompted the need to develop more efficient methods of irrigation. We investigated the effects of a subsurface drip irrigation system at three lev...
Increased food production and reduced water use through optimized crop distribution
NASA Astrophysics Data System (ADS)
Davis, Kyle Frankel; Rulli, Maria Cristina; Seveso, Antonio; D'Odorico, Paolo
2017-12-01
Growing demand for agricultural commodities for food, fuel and other uses is expected to be met through an intensification of production on lands that are currently under cultivation. Intensification typically entails investments in modern technology — such as irrigation or fertilizers — and increases in cropping frequency in regions suitable for multiple growing seasons. Here we combine a process-based crop water model with maps of spatially interpolated yields for 14 major food crops to identify potential differences in food production and water use between current and optimized crop distributions. We find that the current distribution of crops around the world neither attains maximum production nor minimum water use. We identify possible alternative configurations of the agricultural landscape that, by reshaping the global distribution of crops within current rainfed and irrigated croplands based on total water consumption, would feed an additional 825 million people while reducing the consumptive use of rainwater and irrigation water by 14% and 12%, respectively. Such an optimization process does not entail a loss of crop diversity, cropland expansion or impacts on nutrient and feed availability. It also does not necessarily invoke massive investments in modern technology that in many regions would require a switch from smallholder farming to large-scale commercial agriculture with important impacts on rural livelihoods.
Monitoring and modeling agricultural drought for famine early warning (Invited)
NASA Astrophysics Data System (ADS)
Verdin, J. P.; Funk, C.; Budde, M. E.; Lietzow, R.; Senay, G. B.; Smith, R.; Pedreros, D.; Rowland, J.; Artan, G. A.; Husak, G. J.; Michaelsen, J.; Adoum, A.; Galu, G.; Magadzire, T.; Rodriguez, M.
2009-12-01
The Famine Early Warning Systems Network (FEWS NET) makes quantitative estimates of food insecure populations, and identifies the places and periods during which action must be taken to assist them. Subsistence agriculture and pastoralism are the predominant livelihood systems being monitored, and they are especially drought-sensitive. At the same time, conventional climate observation networks in developing countries are often sparse and late in reporting. Consequently, remote sensing has played a significant role since FEWS NET began in 1985. Initially there was heavy reliance on vegetation index imagery from AVHRR to identify anomalies in landscape greenness indicative of drought. In the latter part of the 1990s, satellite rainfall estimates added a second, independent basis for identification of drought. They are used to force crop water balance models for the principal rainfed staple crops in twenty FEWS NET countries. Such models reveal seasonal moisture deficits associated with yield reduction on a spatially continuous basis. In 2002, irrigated crops in southwest Asia became a concern, and prompted the implementation of a gridded energy balance model to simulate the seasonal mountain snow pack, the main source of irrigation water. MODIS land surface temperature data are also applied in these areas to directly estimate actual seasonal evapotranspiration on the irrigated lands. The approach reveals situations of reduced irrigation water supply and crop production due to drought. The availability of MODIS data after 2000 also brought renewed interest in vegetation index imagery. MODIS NDVI data have proven to be of high quality, thanks to significant spectral and spatial resolution improvements over AVHRR. They are vital to producing rapid harvest assessments for drought-impacted countries in Africa and Asia. The global food crisis that emerged in 2008 has led to expansion of FEWS NET monitoring to over 50 additional countries. Unlike previous practice, these new countries have no local FEWS NET analysts, requiring increased reliance on remote sensing for detection of agricultural drought and potential food insecurity. USGS is increasing its cooperation with NASA, NOAA, and university partners to meet this challenge. New servers for near real time delivery of MODIS NDVI, satellite rainfall estimates, and gridded snow pack estimates are being established. A custom instance of NASA's Land Information System software is also being developed to create a land data assimilation system specifically for FEWS NET domains, data streams, and monitoring and forecast requirements. The system will take better advantage of remote sensing data, including promising new products from the Soil Moisture Active-Passive (SMAP) mission, by integrating them with surface observations for simulation of land surface processes. In this way, the continuous improvement of monitoring and modeling for famine early warning will advance to a new level of sophistication and effectiveness.
USDA-ARS?s Scientific Manuscript database
No-tillage (NT) residue management provides cover to increase precipitation capture compared with disk tillage (DT) or in the absence of a cover crop. Therefore, NT has the potential to reduce irrigation withdrawals from the declining Ogallala Aquifer. In a 4-year study, we quantified DT and NT effe...
Soil water sensing: Implications of sensor capabilities for variable rate irrigation management
USDA-ARS?s Scientific Manuscript database
Irrigation scheduling using soil water sensors aims at maintaining the soil water content in the crop root zone above a lower limit defined by the management allowed depletion (MAD) for that soil and crop, but not so wet that too much water is lost to deep percolation, evaporation and runoff or that...
USDA-ARS?s Scientific Manuscript database
Liming agents in irrigation water, typically associated with carbonates and bicarbonates of calcium and magnesium, contribute to water alkalinity. Repeated application of LA to container crops can cause media-solution pH to rise overtime, that uncorrected, can lead to a nutrient availability imbalan...
USDA-ARS?s Scientific Manuscript database
On-farm water recycling is in agricultural landscapes today, and a few examples exist in the Great Lakes region. They have been implemented primarily where both irrigation is needed for high value crops and groundwater is inadequate to provide the rates needed. Crop yield benefits of irrigation fr...
USDA-ARS?s Scientific Manuscript database
Due to the differential crop responses to water stress at different growth stages, scheduling irrigation within a crop season is a challenge facing agricultural producers, especially when water availability varies on a monthly, seasonal and yearly basis. The objective of this study was to optimize i...
NASA Astrophysics Data System (ADS)
Al Zayed, Islam Sabry; Elagib, Nadir Ahmed
2017-12-01
This study proposes a novel monitoring tool based on Satellite Remote Sensing (SRS) data to examine the status of water distribution and Water Use Efficiency (WUE) under changing water policies in large-scale and complex irrigation schemes. The aim is to improve our understanding of the water-food nexus in such schemes. With a special reference to the Gezira Irrigation Scheme (GeIS) in Sudan during the period 2000-2014, the tool devised herein is well suited for cases where validation data are absent. First, it introduces an index, referred to as the Crop Water Consumption Index (CWCI), to assess the efficiency of water policies. The index is defined as the ratio of actual evapotranspiration (ETa) over agricultural areas to total ETa for the whole scheme where ETa is estimated using the Simplified Surface Energy Balance model (SSEB). Second, the tool uses integrated Normalized Difference Vegetation Index (iNDVI), as a proxy for crop productivity, and ETa to assess the WUE. Third, the tool uses SSEB ETa and NDVI in an attempt to detect wastage of water. Four key results emerged from this research as follows: 1) the WUE has not improved despite the changing agricultural and water policies, 2) the seasonal ETa can be used to detect the drier areas of GeIS, i.e. areas with poor irrigation water supply, 3) the decreasing trends of CWCI, slope of iNDVI-ETa linear regression and iNDVI are indicative of inefficient utilization of irrigation water in the scheme, and 4) it is possible to use SSEB ETa and NDVI to identify channels with spillover problems and detect wastage of rainwater that is not used as a source for irrigation. In conclusion, the innovative tool developed herein has provided important information on the efficiency of a large-scale irrigation scheme to help rationalize laborious water management processes and increase productivity.
The surface renewal method for better spatial resolution of evapotranspiration measurements
NASA Astrophysics Data System (ADS)
Suvocarev, K.; Fischer, M.; Massey, J. H.; Reba, M. L.; Runkle, B.
2017-12-01
Evaluating feasible irrigation strategies when water is scarce requires measurements or estimations of evapotranspiration (ET). Direct observations of ET from agricultural fields are preferred, and micrometeorological methods such as eddy covariance (EC) provide a high quality, continuous time series of ET. However, when replicates of the measurements are needed to compare irrigation strategies, the cost of such experiments is often prohibitive and limits experimental scope. An alternative micrometeorological approach to ET, the surface renewal (SR) method, may be reduced to a thermocouple and a propeller anemometer (Castellvi and Snyder, 2009). In this case, net radiation, soil and sensible heat flux (H) are measured and latent heat flux (an energy equivalent for ET) is estimated as the residual of the surface energy-balance equation. In our experiment, thermocouples (Type E Fine-Wire Thermocouple, FW3) were deployed next to the EC system and combined with mean horizontal wind speed measurements to obtain H using SR method for three weeks. After compensating the temperature signal for non-ideal frequency response in the wavelet half-plane and correcting the sonic anemometer for the flow distortion (Horst et al., 2015), the SR H fluxes compared well to those measured by EC (r2 = 0.9, slope = 0.92). This result encouraged us to install thermocouples over 16 rice fields under different irrigation treatments (continuous cascade flood, continuous multiple inlet rice irrigation, alternate wetting and drying, and furrow irrigation). The EC measurements with net radiometer and soil heat flux plates are deployed at three of these fields to provide a direct comparison. The measurement campaign will finish soon and the data will be processed to evaluate the SR approach for ET estimation. The results will be used to show better spatial resolution of ET measurements to support irrigation decisions in agricultural crops.
A Real-time Irrigation Forecasting System in Jiefangzha Irrigation District, China
NASA Astrophysics Data System (ADS)
Cong, Z.
2015-12-01
In order to improve the irrigation efficiency, we need to know when and how much to irrigate in real time. If we know the soil moisture content at this time, we can forecast the soil moisture content in the next days based on the rainfall forecasting and the crop evapotranspiration forecasting. Then the irrigation should be considered when the forecasting soil moisture content reaches to a threshold. Jiefangzha Irrigation District, a part of Hetao Irrigation District, is located in Inner Mongolia, China. The irrigated area of this irrigation district is about 140,000 ha mainly planting wheat, maize and sunflower. The annual precipitation is below 200mm, so the irrigation is necessary and the irrigation water comes from the Yellow river. We set up 10 sites with 4 TDR sensors at each site (20cm, 40cm, 60cm and 80cm depth) to monitor the soil moisture content. The weather forecasting data are downloaded from the website of European Centre for Medium-Range Weather Forecasts (ECMWF). The reference evapotranspiration is estimated based on FAO-Blaney-Criddle equation with only the air temperature from ECMWF. Then the crop water requirement is forecasted by the crop coefficient multiplying the reference evapotranspiration. Finally, the soil moisture content is forecasted based on soil water balance with the initial condition is set as the monitoring soil moisture content. When the soil moisture content reaches to a threshold, the irrigation warning will be announced. The irrigation mount can be estimated through three ways: (1) making the soil moisture content be equal to the field capacity; (2) making the soil moisture saturated; or (3) according to the irrigation quota. The forecasting period is 10 days. The system is developed according to B2C model with Java language. All the databases and the data analysis are carried out in the server. The customers can log in the website with their own username and password then get the information about the irrigation forecasting and other information about the irrigation. This system can be expanded in other irrigation districts. In future, it is even possible to upgrade the system for the mobile user.
NASA Astrophysics Data System (ADS)
Serrano-Coronel, Genaro; Chipana-Rivera, René; Fátima Moreno-Pérez, María; Roldán-Cañas, José
2016-04-01
Among the most important hydraulic structures of pre-Hispanic ancestral technology developed in the Andean region, we find the suka kollus, aymara word, called also waru waru, en quechua or raised fields, in English. They are raised platforms surrounded by water canals that irrigate subsurface, but also have the function of draining, to deal with floods because they are surrounding Lake Titicaca. They also have the property of generating a thermoregulatory effect to crops, depending on the configuration of the channels and platforms. Such agro-ecosystems are being abandoned, however, if properly addressed crop management and some drainage canals are replaced by underground drains for increased crop area could be very useful in enabling marginal soils affected by salts and / or excess water. For these reasons, the objective of this study was to evaluate the subsurface irrigation in the potato crop in suka kollus under a system of surface drainage, and mixed drainage (surface and subsurface). The study was conducted in marginal soils of Kallutaca area, located 30 km from the city of La Paz, Bolivia, at a height of 3892 m.a.s.l. The cultivation of the potato (Solanum tuberosum ssp. Andigena) was used. Four treatments were tested with different widths of the platforms: T1 (Control) with drainage through channels; T2 (replacing a channel by a drain); T3 (replacing two channels by two drains); T4 (replacing three channels by three drains). The flow of water into the soil from the water table was predominantly upward, except during periods of high rainfall. In terms of treatments, the flow in T1 was higher, mainly at weeks 8 to 11 after seedling emergence, coinciding with the phenological phases of flowering and at the beginning of the tuber ripening. It was followed by T3, T2 and T4 treatments, respectively. Tuber yield, if one considers that the channels detract arable land, was higher in the T3 treatment,16.4 Mg / ha, followed by T2 treatment, 15.2 Mg / ha, T1 treatment (Control) 7.3 Mg / ha and T4 treatment with 7.1 Mg / ha. Therefore, in the mixed system with two drains the best results were obtained.
NASA Astrophysics Data System (ADS)
Fader, M.; Shi, S.; von Bloh, W.; Bondeau, A.; Cramer, W.
2015-08-01
Irrigation in the Mediterranean is of vital importance for food security, employment and economic development. This study systematically assesses how climate change and increases in atmospheric CO2 concentrations may affect irrigation requirements in the Mediterranean region by 2080-2090. Future demographic change and technological improvements in irrigation systems are accounted for, as is the spread of climate forcing, warming levels and potential realization of the CO2-fertilization effect. Vegetation growth, phenology, agricultural production and irrigation water requirements and withdrawal were simulated with the process-based ecohydrological and agro-ecosystem model LPJmL after a large development that comprised the improved representation of Mediterranean crops. At present the Mediterranean region could save 35 % of water by implementing more efficient irrigation and conveyance systems. Some countries like Syria, Egypt and Turkey have higher saving potentials than others. Currently some crops, especially sugar cane and agricultural trees, consume in average more irrigation water per hectare than annual crops. Different crops show different magnitude of changes in net irrigation requirements due to climate change, being the increases most pronounced in agricultural trees. The Mediterranean area as a whole might face an increase in gross irrigation requirements between 4 and 18 % from climate change alone if irrigation systems and conveyance are not improved (2 °C global warming combined with full CO2-fertilization effect, and 5 °C global warming combined with no CO2-fertilization effect, respectively). Population growth increases these numbers to 22 and 74 %, respectively, affecting mainly the Southern and Eastern Mediterranean. However, improved irrigation technologies and conveyance systems have large water saving potentials, especially in the Eastern Mediterranean, and may be able to compensate to some degree the increases due to climate change and population growth. Both subregions would need around 35 % more water than today if they could afford some degree of modernization of irrigation and conveyance systems and benefit from the CO2-fertilization effect. Nevertheless, water scarcity might pose further challenges to the agricultural sector: Algeria, Libya, Israel, Jordan, Lebanon, Syria, Serbia, Morocco, Tunisia and Spain have a high risk of not being able to sustainably meet future irrigation water requirements in some scenarios. The results presented in this study point to the necessity of performing further research on climate-friendly agro-ecosystems in order to assess, on the one side, their degree of resilience to climate shocks, and on the other side, their adaptation potential when confronted with higher temperatures and changes in water availability.
[Water-saving mechanisms of intercropping system in improving cropland water use efficiency].
Zhang, Feng-Yun; Wu, Pu-Te; Zhao, Xi-Ning; Cheng, Xue-Feng
2012-05-01
Based on the multi-disciplinary researches, and in terms of the transformation efficiency of surface water to soil water, availability of cropland soil water, crop canopy structure, total irrigation volume needed on a given area, and crop yield, this paper discussed the water-saving mechanisms of intercropping system in improving cropland water use efficiency. Intercropping system could promote the full use of cropland water by plant roots, increase the water storage in root zone, reduce the inter-row evaporation and control excessive transpiration, and create a special microclimate advantageous to the plant growth and development. In addition, intercropping system could optimize source-sink relationship, provide a sound foundation for intensively utilizing resources temporally and spatially, and increase the crop yield per unit area greatly without increase of water consumption, so as to promote the crop water use efficiency effectively.
Climate change, water rights, and water supply: The case of irrigated agriculture in Idaho
NASA Astrophysics Data System (ADS)
Xu, Wenchao; Lowe, Scott E.; Adams, Richard M.
2014-12-01
We conduct a hedonic analysis to estimate the response of agricultural land use to water supply information under the Prior Appropriation Doctrine by using Idaho as a case study. Our analysis includes long-term climate (weather) trends and water supply conditions as well as seasonal water supply forecasts. A farm-level panel data set, which accounts for the priority effects of water rights and controls for diversified crop mixes and rotation practices, is used. Our results indicate that farmers respond to the long-term surface and ground water conditions as well as to the seasonal water supply variations. Climate change-induced variations in climate and water supply conditions could lead to substantial damages to irrigated agriculture. We project substantial losses (up to 32%) of the average crop revenue for major agricultural areas under future climate scenarios in Idaho. Finally, farmers demonstrate significantly varied responses given their water rights priorities, which imply that the distributional impact of climate change is sensitive to institutions such as the Prior Appropriation Doctrine.
Optimizing wind pumps system for crop irrigation based on wind data processing
NASA Astrophysics Data System (ADS)
Ruiz, Fernando; Tarquis, Ana M.; Sanchez, Raúl; Garcia, Jose Luis
2015-04-01
Crop irrigation is a major consumer of energy that can be resolved with renewable ones, such as wind, which has experienced recent developments in the area of power generation. Therefore, wind power can play an interesting role in irrigation projects in different areas [1]. A simple methodology has been developed in previous papers for technical evaluation of windmills for irrigation water pumping [2]. This methodology can determine the feasibility of the technology and the levels of daily irrigation demand satisfied by windmills. The present work compared the possibilities of this methodology adjusting the three-hourly wind velocity to the Weibull II distribution function, without considering the time sequence [2], or processing wind data using time series analysis. The study was applied to practical cases of wind pumps for irrigation of crops, both in the outside (corn) and inside greenhouses (tomato). The analysis showed that the use of three hourly time series analysis supplied a more realistic modelling of the situation with a better optimization of the water storage tank of the wind pump facility taking into account the risk of calm periods in which the pumping is null. A factor to consider in this study is available precision of the wind sampling rate. References [1] Díaz-Méndez, R., Adnan Rasheed, M. Peillón, A. Perdigones, R. Sánchez, A.M. Tarquis, José L. García-Fernández. Wind pumps for irrigating greenhouse crops: comparison in different socio-economical frameworks. Biosystems Engineering, 128, 21-28, 2014. [2] Peillón, M., Sánchez, R., Tarquis, A.M., García, J.L. The use of wind pumps for greenhouse microirrigation: A case study for tomato in Cuba. Agricultural Water Management, 120, 107-114, 2013.
Irrigation trends in Kansas, 1991-2011
Kenny, Joan F.; Juracek, Kyle E.
2013-01-01
This fact sheet examines trends in total reported irrigation water use and acres irrigated as well as irrigation water use by crop type and system type in Kansas for the years 1991 through 2011. During the 21-year period, total reported irrigation water diversions varied substantially from year to year as affected primarily by climatic fluctuations. Total reported acres irrigated remained comparatively constant during this time, although acreages of irrigated corn increased and center pivots with drop nozzles became the dominant system type used for irrigation.
Riediger, Jan; Breckling, Broder; Nuske, Robert S; Schröder, Winfried
2014-01-01
By example of a region in Northern Germany (County of Uelzen), this study investigates whether climate change is likely to require adaption of agricultural practices such as irrigation in Central Europe. Due to sandy soils with low water retention capacity and occasional insufficient rainfall, irrigation is a basic condition for agricultural production in the county of Uelzen. Thus, in the framework of the comprehensive research cluster Nachhaltiges Landmanagement im Norddeutschen Tiefland ( NaLaMa-nT ), we investigated whether irrigation might need to be adapted to changing climatic conditions. To this end, results from regionalised climate change modelling were coupled with soil- and crop-specific evapotranspiration models to calculate potential amounts of irrigation to prevent crop failures. Three different runs of the climate change scenario RCP 8.5 were used for the time period until 2070. The results show that the extent of probable necessary irrigation will likely increase in the future. For the scenario run with the highest temperature rise, the results suggest that the amount of ground water presently allowed to be extracted for irrigation might not be sufficient in the future to retain common agricultural pattern. The investigation at hand exemplifies data requirements and methods to estimate irrigation needs under climate change conditions. Restriction of ground water withdrawal by German environmental regulation may require an adaptation of crop selection and alterations in agricultural practice also in regions with comparable conditions.
Small Scale Irrigation within Water, Energy and Food Nexus Framework in Ethiopia.
NASA Astrophysics Data System (ADS)
Gerik, T.; Worqlul, A. W.; Yihun, D.; Bizimana, J. C.; Jeong, J.; Schmitter, P.; Srinivasan, R.; Richardson, J. W.; Clark, N.
2017-12-01
This study presents the nexus of food, energy and water framework in the context of small scale irrigation for vegetable production during the dry season in an irrigated agriculture system in Ethiopia. The study is based on detailed data collected in three sites of the Innovation Lab for Small Scale Irrigation (ILSSI) project in Ethiopia. The sites were Robit, Dangishta and Lemo and detailed field data was collected in 18 households in each site. The field data collected includes crop management (such as irrigation amount and dates, fertilizer rates, tillage practices, irrigation technologies, etc.) and agricultural production (crop yield, biomass, etc.) on tomato, onion and cabbage during the dry season. Four different water lifting technologies - namely rope with pulley and bucket, rope and washer pump, solar pump and motor pump - were used for water withdrawal from shallow groundwater wells. The Soil and Water Assessment Tool (SWAT) and Agricultural Policy Environmental eXtender (APEX) models were used in an integrated manner to assess water resource potential and develop water use efficiency of vegetables, which is a relationship between amount of water applied and vegetable yield. The water use efficiency for each vegetable crops were translated into energy requirement as pumping hours and potential irrigable areas for the water lifting technologies. This integrated approach was found useful to optimize water and energy use for sustainable food production using small scale irrigation. The holistic approach will not only provide a significant contribution to achieving food self-sufficiency, but will also be effective for optimizing agricultural input. Keyword: small scale irrigation, integrated modeling, water lifting technology, East Africa
NASA Astrophysics Data System (ADS)
Mangiarotti, S.; Muddu, S.; Sharma, A. K.; Corgne, S.; Ruiz, L.; Hubert-Moy, L.
2015-12-01
Groundwater is one of the main water reservoirs used for irrigation in regions of scarce water resources. For this reason, crop irrigation is expected to have a direct influence on this reservoir. To understand the time evolution of the groundwater table and its storage changes, it is important to delineate irrigated crops, whose evaporative demand is relatively higher. Such delineation may be performed based on classical classification approaches using optical remote sensing. However, it remains a difficult problem in regions where plots do not exceed a few hectares and exhibit a very heterogeneous pattern with multiple crops. This difficulty is emphasized in South India where two or three months of cloudy conditions during the monsoon period can hide crop growth during the year. An alternative approach is introduced here that takes advantage of such scarce signal. Ten different crops are considered in the present study. A bank of crop models is first established based on the global modeling technique [1]. These models are then tested using original time series (from which models were obtained) in order to evaluate the information that can be deduced from these models in an inverse approach. The approach is then tested on an independent data set and is finally applied to a large ensemble of 10,000 time series of plot data extracted from the Berambadi catchment (AMBHAS site) part of the Kabini River basin CZO, South India. Results show that despite the important two-month gap in satellite observations in the visible band, interpolated vegetation index remains an interesting indicator for identification of crops in South India. [1] S. Mangiarotti, R. Coudret, L. Drapeau, & L. Jarlan, Polynomial search and global modeling: Two algorithms for modeling chaos, Phys. Rev. E, 86(4), 046205 (2012).
Lu, Shibao; Wang, Jianhua; Pei, Liang
2016-01-01
Reclaimed water is an important resource for irrigation, and exploration in making full use of it is an important way to alleviate water shortage. This paper analyzes the effects of irrigation with reclaimed water through field trials on the content and distribution of heavy metals in both tomatoes and the soil. By exploring the effects of reclaimed water after secondary treatment on the content and distribution characteristics of heavy metals in tomatoes and the heavy metal balance in the soil-crop system under different conditions, the study shows that there are no significant differences in the heavy metal content when the quantity of reclaimed water for irrigation varies. Reclaimed water for short-term irrigation does not cause pollution to either the soil environment or the crops. Nor will it cause the accumulation of heavy metals, and the index for the heavy metal content is far below the critical value of the national standard, which indicates that the vegetables irrigated with reclaimed water during their growth turn out to be free of pollutants. The heavy metals brought into the soil by reclaimed water are less than that taken away by the crops. The input and output quantities have only small effects on the heavy metal balance in the soil. This paper provides a reference for the evaluation and safety control of irrigation with reclaimed water. PMID:27005639
Lu, Shibao; Wang, Jianhua; Pei, Liang
2016-03-08
Reclaimed water is an important resource for irrigation, and exploration in making full use of it is an important way to alleviate water shortage. This paper analyzes the effects of irrigation with reclaimed water through field trials on the content and distribution of heavy metals in both tomatoes and the soil. By exploring the effects of reclaimed water after secondary treatment on the content and distribution characteristics of heavy metals in tomatoes and the heavy metal balance in the soil-crop system under different conditions, the study shows that there are no significant differences in the heavy metal content when the quantity of reclaimed water for irrigation varies. Reclaimed water for short-term irrigation does not cause pollution to either the soil environment or the crops. Nor will it cause the accumulation of heavy metals, and the index for the heavy metal content is far below the critical value of the national standard, which indicates that the vegetables irrigated with reclaimed water during their growth turn out to be free of pollutants. The heavy metals brought into the soil by reclaimed water are less than that taken away by the crops. The input and output quantities have only small effects on the heavy metal balance in the soil. This paper provides a reference for the evaluation and safety control of irrigation with reclaimed water.
NASA Astrophysics Data System (ADS)
Vico, Giulia; Porporato, Amilcare
2014-05-01
The field of ecohydrology, traditionally focusing on natural ecosystems, can offer the necessary quantitative tools to assess and compare the sustainability of agriculture across climates, soil types, crops, and irrigation strategies, including rainfall unpredictability. In particular, irrigation is one of the main strategies to enhance and stabilize agricultural productivity, but represents a cost in terms of often scarce water resources. Here, the sustainability of irrigated and rainfed agriculture is assessed by means of water productivity (defined as the ratio between yield and total supplied water), yields, water requirements, and their variability. These indicators are quantified using a probabilistic description of the soil water balance and crop development. Employing this framework, we interpret changes in water productivity as total water input is altered, in two staple crops (maize and wheat) grown under different soils, climates, and irrigation strategies. Climate change scenarios are explored by using the same approach and altering the rainfall statistics. For a given irrigation strategy, intermediate rainfall inputs leads to the highest variability in yield and irrigation water requirement - it is under these conditions that water management is most problematic. When considering the contrasting needs of limiting water requirements while ensuring adequate yields, micro-irrigation emerges as the most sustainable strategy at the field level, although consideration should be given to its profitability and long-term environmental implications.
NASA Astrophysics Data System (ADS)
Zhu, T.; Cai, X.
2013-12-01
Delay in onset of Indian summer monsoon becomes increasingly frequent. Delayed monsoon and occasional monsoon failures seriously affect agricultural production in the northeast as well as other parts of India. In the Vaishali district of the Bihar State, Monsoon rainfall is very skewed and erratic, often concentrating in shorter durations. Farmers in Vaishali reported that delayed Monsoon affected paddy planting and, consequently delayed cropping cycle, putting crops under the risks of 'terminal heat.' Canal system in the district does not function due to lack of maintenance; irrigation relies almost entirely on groundwater. Many small farmers choose not to irrigate when monsoon onset is delayed due to high diesel price, leading to reduced production or even crop failure. Some farmers adapt to delayed onset of Monsoon by planting short-duration rice, which gives the flexibility for planting the next season crops. Other sporadic autonomous adaptation activities were observed as well, with various levels of success. Adaptation recommendations and effective policy interventions are much needed. To explore robust options to adapt to the changing Monsoon regime, we build a stochastic programming model to optimize revenues of farmer groups categorized by landholding size, subject to stochastic Monsoon onset and rainfall amount. Imperfect probabilistic long-range forecast is used to inform the model onset and rainfall amount probabilities; the 'skill' of the forecasting is measured using probabilities of correctly predicting events in the past derived through hindcasting. Crop production functions are determined using self-calibrating Positive Mathematical Programming approach. The stochastic programming model aims to emulate decision-making behaviors of representative farmer agents through making choices in adaptation, including crop mix, planting dates, irrigation, and use of weather information. A set of technological and policy intervention scenarios are tested, including irrigation subsidies, drought and heat-tolerant crop varieties, and enhancing agricultural extension. A portfolio of prioritized adaption options are recommended for the study area.
Influence of local topography on precision irrigation management
USDA-ARS?s Scientific Manuscript database
Precision irrigation management is currently accomplished using spatial information about soil properties through soil series maps or electrical conductivity (EC measurements. Crop yield, however, is consistently influenced by local topography, both in rain-fed and irrigated environments. Utilizing ...
The impacts of climate change on global irrigation water requirements
NASA Astrophysics Data System (ADS)
Zhang, X.; Cai, X.
2011-12-01
Climate change tends to affect the irrigation water requirement of current irrigated agricultural land, and also changes the water availability for current rain-fed land by the end of this century. We use the most up-to-date climatic and crop datasets (e.g., global irrigated/rain-fed crop areas and grid level crop growing calendar (Portmann, Siebert and Döll, 2010, Global Biogeochemical Cycles 24)) to evaluate the requirements of currently irrigated land and the water deficit for rain-fed land for all major crops under current and projected climate. Six general circulation models (GCMs) under two emission scenarios, A1B & B1, are assembled using two methods, the Simple Average Method (SAM) and Root Mean Square Error Ensemble Method (RMSEMM), to deal with the GCM regional variability. It is found that the global irrigation requirement and the water deficit are both going to increase significantly under all scenarios, particularly under the A1B emission scenario. For example, the projected irrigation requirement is expected to increase by about 2500 million m3 for wheat, 3200 million m3 for maize and another 3300 million m3 for rice. At the same time, the water deficit for current rain-fed cropland will be widened by around 3000, 4000, 2100 million m3 for wheat, maize and rice respectively. Regional analysis is conducted for Africa, China, Europe, India, South America and the United States. It is found that the U.S. may expect the greatest rise in irrigation requirements for wheat and maize, while the South America may suffer the greatest increase for rice. In addition, Africa and the U.S. may face a larger water deficit for both wheat and maize on rain-fed land, and South America just for rice. In summary, climate change is likely to bring severe challenges for irrigation systems and make global water shortage even worse by the end of this century. These pressures will call for extensive adaptation measures. The change in crop water requirements and availability will lead to changes in regional food production, demand and trade, and will affect global food markets. It is also likely that the network and paths of the so-called global virtual water flow will be altered due to the impact of climate change on food production at the regional level.