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1

The green manure value of seven clover species grown as annual crops on low and high fertility temperate soils.  

SciTech Connect

Annual and perennial clover species may differ in green manure value. Seven clover (Trifolium) species were grown as annual crops on low fertility (Breton) and high fertility 15 (Edmonton) soils in Alberta

Ross, Shirley M.; King, Jane R.; Izaurralde, Roberto C.; O'Donovan, John T.

2009-05-01

2

Effects of climatic factors and soil management on the methane flux in soils from annual and perennial energy crops  

Microsoft Academic Search

Methane flux rates were measured on a loamy sand soil within perennial and annual energy crops in northeast Germany. The study\\u000a was performed in closed chambers between 2003 and 2005 with four measurements per week. A mixed linear model including the\\u000a fixed effects of year, rotation period, crop and fertilisation was applied to determine the influence of climatic factors\\u000a and

Jürgen Kern; Hans Jürgen Hellebrand; Michael Gömmel; Christian Ammon; Werner Berg

3

Crop Production: Annual Summary  

NSDL National Science Digital Library

The National Agricultural Statistics Service (NASS) (described in the June 4, 1998 Scout Report for Business and Economics) of the United States Department of Agriculture (USDA) has recently released the annual summary of US crop production. Available in text or .pdf format, the summary contains "annual US data for acreage, yield, and production by crop." In addition to statistical tables, the report includes reviews of crop progress and the weather in 1998. Reports from 1995-98 are also available in text format only.

4

Role of Cover Crops in Improving Soil and Row Crop Productivity  

Microsoft Academic Search

Cover crops play an important role in improving productivity of subsequent row crops by improving soil physical, chemical, and biological properties. The objective of this article is to review recent advances in cover crops practice, in the context of potential benefits and drawbacks for annual crop production and sustained soil quality. Desirable attributes of a cover crop are the ability

N. K. Fageria; V. C. Baligar; B. A. Bailey

2005-01-01

5

Contrasting grain crop and grassland management effects on soil quality properties for a north-central Missouri claypan soil landscape  

Microsoft Academic Search

Crop management has the potential to either enhance or degrade soil quality, which in turn impacts on crop production and the environment. Few studies have investigated how crop management affects soil quality over different landscape positions. The objective of the present study was to investigate how 12 years of annual cropping system (ACS) and conservation reserve program (CRP) practices impacted soil

Won Kyo Jung; Newell R. Kitchen; Kenneth A. Sudduth; Robert J. Kremer

2008-01-01

6

Influence of Herbicide-Desiccated Cover Crops on Biological Soil Quality in the Mississippi Delta  

Microsoft Academic Search

The effect of crop residue management (CRM) systems on selected biological properties (microbial biomass\\/populations and soil enzyme activity) of Dundee soils under two cropping systems was investigated. In a cotton (Gossypium hirsutum L.) study, the influence of conventional tillage (CT) and no-tillage (NT) with and without an annual ryegrass cover crop (Lolium multiforum Lam.) on these properties was determined. Annual

S. C. Wagner; R. M. Zablotowicz; M. A. Locke; R. J. Smeda; C. T. Bryson

7

Reduction of Nitrate Leaching in Agricultural Soils via Cover Crops.  

National Technical Information Service (NTIS)

Field experiments on a Coastal Plain soil (Norfolk loamy sand) served as a basis for characterizing NO3 leaching potential and the subsequent potential of winter annual cover crops (crimson clover, rye, spring oat, wheat, and native weeds) to recover and ...

M. G. Wagger

1996-01-01

8

INSECTICIDE RESIDUES IN COTTON CROP SOIL  

Microsoft Academic Search

Dimethoate, monocrotophos, triazophos, deltamethrin, cypermethrin and endosulfan were applied to a cotton crop soil located at Nurpur village, Punjab, India. The insecticides were applied sequentially at recommended dosages in cotton fields by foliar application in 1995, 1996 and 1998. Soil samples were collected from the cotton crop farms and extracted with acetone. The extracted material was analysed by a gas

Komal Vig; Dileep K. Singh; H. C. Agarwal; A. K. Dhawan; Prem Dureja

2001-01-01

9

Nitrogen mineralization and availability of mixed leguminous and non-leguminous cover crop residues in soil  

Microsoft Academic Search

Whereas non-leguminous cover crops such as cereal rye (Secale cereale) or annual ryegrass (Lolium multiflorium) are capable of reducing nitrogen (N) leaching during wet seasons, leguminous cover crops such as hairy vetch (Vicia villosa) improve soil N fertility for succeeding crops. With mixtures of grasses and legumes as cover crop, the goal of reducing\\u000a N leaching while increasing soil N

S. Kuo; U. M. Sainju

1998-01-01

10

Remote sensing of crop residue cover and soil tillage intensity  

Microsoft Academic Search

Crop residues on the soil surface reduce soil erosion and affect water infiltration, evaporation, and soil temperatures. Crop residues also influence the flow of nutrients, carbon, water, and energy in agricultural ecosystems. Current methods of measuring crop residue cover are inadequate for monitoring large areas. One promising remote sensing approach for discriminating crop residues from soil is based on a

C. S. T. Daughtry; P. C. Doraiswamy; A. L. Russ

2003-01-01

11

Carbon dynamics of perennial grassland conversion for annual cropping  

NASA Astrophysics Data System (ADS)

Sequestering atmospheric carbon in soil is an attractive option for mitigation of rising atmospheric carbon dioxide concentrations through agriculture. Perennial crops are more likely to gain carbon while annual crops are more likely to lose carbon. A pair of eddy covariance towers were set up near Winnipeg Manitoba, Canada to measure carbon flux over adjacent fertilized long-term perennial grass hay fields with high soil organic carbon. In 2009 the forage stand of one field (Treatment) was sprayed with herbicide, cut and bailed; following which cattle manure was applied and the land was tilled. The forage stand in the other field (Control) continued to be cut and bailed. Differences between net ecosystem productivity of the fields were mainly due to gross primary productivity; ecosystem respiration was similar for both fields. When biomass removals and manure applications are included in the carbon balance, the Treatment conversion lost 149 g C m-2 and whereas the Control sequestered 96 g C m-2, for a net loss of 245 g C m-2 over the June to December period (210 days). This suggests that perennial grass converted for annual cropping can lose more carbon than perennial grasses can sequester in a season.

Fraser, Trevor J.

12

Winter cover crops in a vegetable cropping system: Impacts on nitrate leaching, soil water, crop yield, pests and management costs  

Microsoft Academic Search

Plant-soil relationships in the surface soil layer affect other processes in agroecosystems, including crop productivity, nitrate leaching and plant-pest interactions. This study investigated the effect of altering surface soil dynamics, using a winter cover crop rotation, on biotic and abiotic characteristics of the soil profile. Two cover crop treatments, phacelia and Merced rye (Phacelia tanacetifolia cv. ‘Phaci’, and Secale cereale

L. J. Wyland; L. E. Jackson; W. E. Chaney; K. Klonsky; S. T. Koike; B. Kimple

1996-01-01

13

Cropping systems and control of soil erosion in a Mediterranean environment  

NASA Astrophysics Data System (ADS)

The research has been carried out over the years 1996-2010 in an area of the internal hill of Sicily region (Enna, c.da Geracello, 550 m a. s. l. 37° 23' N. Lat, 14° 21' E. Long) in the center of Mediterranean Sea, mainly devoted to durum wheat cultivation, using the experimental plots, established in 1996 on a slope of 26-28%, equipped to determine surface runoff and soil losses. The establishment consists of twelve plots, having 40 m length and 8 m width. In order to study the effect of different field crop systems in controlling soil erosion in slopes subjected to water erosion, the following systems were studied: permanent crops, tilled annual crops, no-tilled annual crops, set-aside. The used crops were: durum wheat, faba bean, rapeseed, subterranean clover, Italian ryegrass, alfalfa, sweetvetch, moon trefoil, barley, sweet sorghum, sunflower. The results pointed out that the cropping systems with perennial crops allowed to keep low the soil loss, while annual crop rotation determined a high amount of soil loss. Sod seeding showed promising results also for annual crop rotations.

Cosentino, Salvatore; Copani, Venera; Testa, Giorgio; Scalici, Giovanni

2013-04-01

14

Micronutrients in Soils, Crops, and Livestock  

NASA Astrophysics Data System (ADS)

Micronutrient concentrations are generally higher in the surface soil and decrease with soil depth. In spite of the high concentration of most micronutrients in soils, only a small fraction is available to plants. Micronutrients, also known as trace elements, are required in microquantities but their lack can cause serious crop production and animal health problems. Crops vary considerably in their response to various micronutrients. Brassicas and legumes are highly responsive to molybdenum (Mo) and boron (B), whereas corn and other cereals are more responsive to zinc (Zn) and copper (Cu). Micronutrient deficiencies are more common in humid temperate regions, as well as in humid tropical regions, because of intense leaching associated with high precipitation. Soil pH is one of the most important factors affecting the availability of micronutrients to plants. With increasing pH, the availability of these nutrients is reduced with the exception of Mo whose availability increases as soil pH increases. In most plant species, leaves contain higher amounts of nutrients than other plant parts. Therefore, whenever possible, leaves should be sampled to characterize the micronutrient status of crops. Deficiency symptoms for most micronutrients appear on the younger leaves at the top of the plant, whereas toxicity symptoms generally appear on the older leaves of plants. As summarized by Deckers and Steinnes, micronutrient deficiencies are widespread in developing countries, which have much poorer soil resources than the fertile soils of Europe and North America. Many of these areas lie in the humid tropics with extremely infertile, highly weathered, and/or highly leached soils, which are intensely deficient in nutrients. The rest of such soils are in the semiarid and areas adjacent to the latter, where alkaline and calcareous soil conditions severely limit the availability of micronutrients to plants. Frequently, the Cu, iron (Fe), manganese (Mn), Zn, and selenium (Se) levels in forages, which are sufficient for optimum crop yields, are not adequate to meet the needs of livestock. Selenium is a trace mineral, which is not required by plants, and maximum forage yields can be obtained on soils with very low amounts of soil Se. However, if animals are fed feed crops and forages with low Se, they could suffer from serious muscular disorders and other diseases. White muscle disease caused by Se deficiency is the most common disorder and is found in calves and lambs. Sufficiency levels of micronutrients for crops have been discussed in relation to the animal requirement.

Gupta, Umesh C.; Wu, Kening; Liang, Siyuan

15

Management of cruciferous cover crops by mowing for soil and water conservation in southern Spain  

Microsoft Academic Search

In recent years, the use of cover crops in Mediterranean olive orchards has increased due to serious soil erosion problems and surface water contamination by herbicides. In these areas, the annual precipitation regime is strongly seasonal, with dry summers that require killing the cover crop before it competes with the trees for water. Cruciferous species are being introduced as cover

C. Alcántara; A. Pujadas; M. Saavedra

2011-01-01

16

Influence of crop rotation and tillage intensity on soil physical properties and functions  

NASA Astrophysics Data System (ADS)

Soil tillage intensity can vary concerning tillage depth, frequency, power input into the soil and degree of soil turn-over. Conventional tillage systems where a plough is regularly used to turn over the soil can be differentiated from reduced tillage systems without ploughing but with loosening the upper soil and no tillage systems. Between conventional tillage and no tillage is a wide range of more or less reduced tillage systems. In our case the different tillage intensities are not induced by different agricultural machinery or techniques, but result from varying crop rotations with more or less perennial crops and therefore lower or higher tillage frequency. Our experimental area constitutes of quite unstructured substrates, partly heavily compacted. The development of a functioning soil structure and accumulation of nutrients and organic matter are of high importance. Three different crop rotations induce varying tillage intensities and frequencies. The first crop rotation (Alfalfa monoculture) has only experienced seed bed preparation once and subsequently is wheeled once a year to cut and chaff the biomass. The second crop rotation contains perennial and annual crops and has therefore been tilled more often, while the third crop rotation consists only of annual crops with annual seedbed preparation. Our results show that reduced tillage intensity/frequency combined with the intense root growth of Alfalfa creates the most favourable soil physical state of the substrate compared to increased tillage and lower root growth intensity of the other crop rotations. Soil tillage disturbs soil structure development, especially when the substrate is mechanically unstable as in our case. For such problematic locations it is recommendable to reduce tillage intensity and/or frequency to allow the development of soil structure enhanced by root growth and thereby the accumulation of organic matter and nutrients within the rooting zone.

Krümmelbein, Julia

2013-04-01

17

Effects of bioenergy crop cultivation on earthworm communities—A comparative study of perennial ( Miscanthus) and annual crops with consideration of graded land-use intensity  

Microsoft Academic Search

Energy crops are of growing importance in agriculture worldwide. This field study aimed to investigate earthworm communities of different intensively cultivated soils during a 2-year period, with special emphasis on annual and perennial energy crops like rapeseed, maize, and Miscanthus. These were compared with cereals, grassland, and fallow sites. Distribution patterns of earthworm abundance, species, and ecological categories were analysed

Daniel Felten; Christoph Emmerling

2011-01-01

18

Impacts of crop growth dynamics on soil quality at the regional scale  

NASA Astrophysics Data System (ADS)

Agricultural land use and in particular crop growth dynamics can greatly affect soil quality. Both the amount of soil lost from erosion by water and soil organic matter are key indicators for soil quality. The aim was to develop a modelling framework for quantifying the impacts of crop growth dynamics on soil quality at the regional scale with test case Flanders. A framework for modelling the impacts of crop growth on soil erosion and soil organic matter was developed by coupling the dynamic crop cover model REGCROP (Gobin, 2010) to the PESERA soil erosion model (Kirkby et al., 2009) and to the RothC carbon model (Coleman and Jenkinson, 1999). All three models are process-based, spatially distributed and intended as a regional diagnostic tool. A geo-database was constructed covering 10 years of crop rotation in Flanders using the IACS parcel registration (Integrated Administration and Control System). Crop allometric models were developed from variety trials to calculate crop residues for common crops in Flanders and subsequently derive stable organic matter fluxes to the soil. Results indicate that crop growth dynamics and crop rotations influence soil quality for a very large percentage. soil erosion mainly occurs in the southern part of Flanders, where silty to loamy soils and a hilly topography are responsible for soil loss rates of up to 40 t/ha. Parcels under maize, sugar beet and potatoes are most vulnerable to soil erosion. Crop residues of grain maize and winter wheat followed by catch crops contribute most to the total carbon sequestered in agricultural soils. For the same rotations carbon sequestration is highest on clay soils and lowest on sandy soils. This implies that agricultural policies that impact on agricultural land management influence soil quality for a large percentage. The coupled REGCROP-PESERA-ROTHC model allows for quantifying the impact of seasonal and year-to-year crop growth dynamics on soil quality. When coupled to a multi-annual crop rotation database both spatial and temporal analysis becomes possible and allows for decision support at both farm and regional level. The framework is therefore suited for further scenario analysis and impact assessment. The research is funded by the Belgian Science Policy Organisation (Belspo) under contract nr SD/RI/03A.

Gobin, Anne

2014-05-01

19

Phosphorus management for perennial crops in central Amazonian upland soils  

Microsoft Academic Search

The present contribution discusses the soil P status of central Amazonian upland soils, the effects of tree crops on soil P availability and the factors controlling soil P cycling in land use systems with tree crops. Soil fertility management has to target the prevalent P deficiency by adequate P fertilization, especially in southern and northern municipalities of central Amazônia where

Johannes Lehmann; Manoel da Silva Cravo; Jeferson Luiz; Vasconselos de Macêdo

2001-01-01

20

Soil carbon sequestration via cover crops- A meta-analysis  

NASA Astrophysics Data System (ADS)

Agricultural soils are depleted in soil organic carbon (SOC) and have thus a huge potential to sequester SOC. This can primarily be achieved by increasing carbon inputs into the soil. Replacing winter fallows by cover crop cultivation for green manure has many benefits for the soil and forms an additional carbon input. An increase in carbon concentration has been reported in several studies worldwide. However, the effect on SOC stocks, as well as the influence of environmental parameters and management on SOC dynamics is not known. We therefore conducted a meta-analysis to investigate those issues. A total of 33 studies, comprising 47 sites and 147 plots were compiled. A pedotransfer function was used to estimate bulk densities and calculate SOC stocks. SOC stock change was found to be a linear function of time since introduction, with an annual sequestration rate of 0.32 Mg C ha-1 yr-1. Since no saturation was visible in the observations, we used the model RothC to estimate a new steady state level and the resulting total SOC stock change for an artificial "average cropland". The total average SOC stock change with an annual input of 1.87 Mg C ha-1 yr-1 was 16.76 Mg C ha-1 for the average soil depth of 22 cm. We estimated a potential global SOC sequestration of 0.12±0.03 Pg C yr-1, which would compensate for 8 % of the direct annual greenhouse gas emissions from agriculture.

Poeplau, Christopher; Don, Axel

2014-05-01

21

Pendimethalin Wash?Off from Cover Crop Residues and Degradation in a Loessial Soil  

Microsoft Academic Search

Tillage and cover crops affect soil biological, chemical and physical properties that control the fate of herbicides in soil. Effects of conventional tillage (CT) and no tillage (NT) and either native winter annual vegetation, hairy vetch (Vicia villosa) or wheat (Triticum aestivum) on degradation of pendimethalin [N?(1?ethylpropyl)?3,4?dimethyl?2,6?dinitrobenzenamine] were investigated. Effect of pendimethalin sorption on residues of these cover crops on

L. A. Gaston; D. J. Boquet; M. A. Bosch

2003-01-01

22

Remote sensing of crop residue cover and soil tillage intensity  

Microsoft Academic Search

Management of plant litter or crop residues in agricultural fields is an important consideration for reducing soil erosion and increasing soil organic C. Current methods of quantifying crop residue cover are inadequate for characterizing the spatial variability of residue cover within fields or across large regions. Our objectives were to evaluate several spectral indices for measuring crop residue cover using

C. S. T. Daughtry; P. C. Doraiswamy; E HUNTJR; A. J. Stern; J MCMURTREYIII; J. H. Prueger

2006-01-01

23

Discriminating Crop Residues from Soil by Shortwave Infrared Reflectance  

Microsoft Academic Search

in the line-transect method with a sensor designed to identify crop residue based on its reflectance character- Quantifying crop residue cover on the soil surface is important for istics have had only limited success. The reflectance of evaluating the effectiveness of conservation tillage practices. Current methods of measuring residue cover are inadequate in characterizing both soils and crop residues lack

Craig S. T. Daughtry

2001-01-01

24

Earthworms and weed seed distribution in annual crops  

Microsoft Academic Search

A field study was conducted to determine if earthworm activity would affect the abundance and composition of weed seed banks in annual row-crops. The abundance of weed seeds in surface-deposited earthworm casts was determined in continuous monocultures and rotations that included corn, soybean, and winter wheat, with or without cover crop. Casts were collected weekly over the growing season and

R. G. Smith; K. L. Gross; S. Januchowski

2005-01-01

25

Short-term incorporation of organic manures and biofertilizers influences biochemical and microbial characteristics of soils under an annual crop [Turmeric ( Curcuma longa L.)  

Microsoft Academic Search

The study was conducted to determine whether short-term incorporation of organic manures and biofertilizers influence biochemical and microbial variables reflecting soil quality. For the study, soils were collected from a field experiment conducted on turmeric (Curcuma longa L.) involving organic nutrient management (ONM), chemical nutrient management (CNM) and integrated nutrient management (INM). The findings revealed that application of organic manures

R. Dinesh; V. Srinivasan; S. Hamza; A. Manjusha

2010-01-01

26

Measuring and modelling soil evaporation in wheat crops  

Microsoft Academic Search

Soil evaporation is often an important component of the total water loss from plant canopies, but is poorly estimated in many SVAT models. This paper reports the use of micrometeorological and lysimetric methods to measure soil evaporation (Es) in the canopy of a wheat crop over a period of 7 weeks as the crop matured and green leaf area index

O. T. Denmead; F. X. Dunin; R. Leuning; M. R. Raupach

1996-01-01

27

Fractions of organic carbon in soils under different crop rotations, cover crops and fertilization practices  

Microsoft Academic Search

We investigated the long-term effects (13–48 years) of crop rotations, cover crops and fertilization practices on soil organic carbon fractions. Two long-term experiments conducted on a clay loam soil in southeastern Norway were used. From the crop rotation experiment, two rotations, one with two years grain + four years grass and the second with grain alone (both for 6 years),

Z. Yang; B. R. Singh; B. K. Sitaula

2004-01-01

28

Impact of crop rotation and phenological periods on rhodanese activity and free sulfuric amino acids concentrations in soils under continuous rye cropping and crop rotation  

Microsoft Academic Search

Rhodanese activity as well as the concentrations of free sulfuric amino acids in soil under continuous rye cropping and crop rotation were studied. Experiments were carried out in different phenological periods of plants. In soil under continuous rye cropping, higher concentrations of free sulfuric amino acid and higher values of rhodanese activity were found than in soil under crop rotation.

Lech Szajdak

1996-01-01

29

Impacts of crop rotations on soil organic carbon sequestration  

NASA Astrophysics Data System (ADS)

Agricultural land use and crop rotations can greatly affect the amount of carbon sequestered in the soil. We developed a framework for modelling the impacts of crop rotations on soil carbon sequestration at the field scale with test case Flanders. A crop rotation geo-database was constructed covering 10 years of crop rotation in Flanders using the IACS parcel registration (Integrated Administration and Control System) to elicit the most common crop rotation on major soil types in Flanders. In order to simulate the impact of crop cover on carbon sequestration, the Roth-C model was adapted to Flanders' environment and coupled to common crop rotations extracted from the IACS geodatabases and statistical databases on crop yield. Crop allometric models were used to calculate crop residues from common crops in Flanders and subsequently derive stable organic matter fluxes to the soil (REGSOM). The REGSOM model was coupled to Roth-C model was run for 30 years and for all combinations of seven main arable crops, two common catch crops and two common dosages of organic manure. The common crops are winter wheat, winter barley, sugar beet, potato, grain maize, silage maize and winter rapeseed; the catch crops are yellow mustard and Italian ryegrass; the manure dosages are 35 ton/ha cattle slurry and 22 ton/ha pig slurry. Four common soils were simulated: sand, loam, sandy loam and clay. In total more than 2.4 million simulations were made with monthly output of carbon content for 30 years. Results demonstrate that crop cover dynamics influence carbon sequestration for a very large percentage. For the same rotations carbon sequestration is highest on clay soils and lowest on sandy soils. Crop residues of grain maize and winter wheat followed by catch crops contribute largely to the total carbon sequestered. This implies that agricultural policies that impact on agricultural land management influence soil carbon sequestration for a large percentage. The framework is therefore suited for further scenario analysis and impact assessment in order to support agri-environmental policy decisions.

Gobin, Anne; Vos, Johan; Joris, Ingeborg; Van De Vreken, Philippe

2013-04-01

30

Long-term effects of agronomic practices on soil organic carbon and crop productivity in the internal hills of Sicily  

NASA Astrophysics Data System (ADS)

In the hilly areas of Mediterranean environment the high intensity of autumnal rains determines high level of soil erosion losses in agricultural field reducing the soil fertility in the long run. In Sicily region this phenomenon have been emphasized by the crop management and by the orography of the territory. The experimental farm of UNICT for the collection of surface runoff is located in the c.da Manca di Geracello, Enna (550 m a.s.l, 37° 21'N, 14°16'E). The establishment consists of 12 plots. In the last sixteen years (1996-2011) the study of the impact assessment of various herbaceous cropping systems, both in terms of crop rotation (one crop, alternating different crops), crop habit (annual or perennials), types of soil tillage (traditional, minimum tillage, no tillage) on the dynamics of soil organic matter was carried out. The soil organic matter content, according to the depth of measurement (0-30 and 31-60 cm), the portion on the plot where the sample was taken (high, medium, low), and the season (winter and summer), was found significantly different according to the different cropping systems. The variation of organic matter in time was depending upon the soil tillage (plowing or not and sod seeding), the habitus of crop (annual or perennial). In the case of perennial the organic matter increased from 1.2 to 2.2%. The sod seeding allowed to take the organic matter around 1.8-2.0%

Cosentino, Salvatore; Copani, Venera; Testa, Giorgio; Scordia, Danilo

2013-04-01

31

Impact of Corn Residue Removal on Crop and Soil Productivity  

NASA Astrophysics Data System (ADS)

Over-reliance on imported fuels, increasing atmospheric levels of greenhouses and sustaining food production for a growing population are three of the most important problems facing society in the mid-term. The US Department of Energy and private enterprise are developing technology necessary to use high cellulose feedstock, such as crop residues, for ethanol production. Based on production levels, corn (Zea mays L.) residue has potential as a biofuel feedstock. Crop residues are a renewable and domestic fuel source, which can reduce the rate of fossil fuel use (both imported and domestic) and provide an additional farm commodity. Crop residues protect the soil from wind and water erosion, provide inputs to form soil organic matter (a critical component determining soil quality) and play a role in nutrient cycling. Crop residues impact radiation balance and energy fluxes and reduce evaporation. Therefore, the benefits of using crop residues as fuel, which removes crop residues from the field, must be balanced against negative environmental impacts (e.g. soil erosion), maintaining soil organic matter levels, and preserving or enhancing productivity. All ramifications of new management practices and crop uses must be explored and evaluated fully before an industry is established. There are limited numbers of long-term studies with soil and crop responses to residue removal that range from negative to negligible. The range of crop and soil responses to crop residue removal was attributed to interactions with climate, management and soil type. Within limits, corn residue can be harvested for ethanol production to provide a renewable, domestic source of energy feedstock that reduces greenhouse gases. Removal rates must vary based on regional yield, climatic conditions and cultural practices. Agronomists are challenged to develop a protocol (tool) for recommending maximum permissible removal rates that ensure sustained soil productivity.

Johnson, J. M.; Wilhelm, W. W.; Hatfield, J. L.; Voorhees, W. B.; Linden, D.

2003-12-01

32

Soil carbon, soil nitrate, and soil emissions of nitrous oxide during cultivation of energy crops  

Microsoft Academic Search

Carbon (C) sequestration and soil emissions of nitrous oxide (N2O) affect the carbon dioxide (CO2) advantage of energy crops. A long-term study has been performed to evaluate the environmental effects of energy crop cultivation\\u000a on the loamy sand soil of the drier northeast region of Germany. The experimental field, established in 1994, consisted of\\u000a columns (0.25 ha each) cultivated with short

Hans J. Hellebrand; Martin Strähle; Volkhard Scholz; Jürgen Kern

2010-01-01

33

Restoration of soil organic carbon with cultivation of perennial biofuel crops  

NASA Astrophysics Data System (ADS)

A biofuel crop that can restore soil quality and maximize terrestrial carbon (C) sequestration would add substantial value to the sustainability of biofuel production chains. Currently in the Midwestern USA, Zea mays is the dominant biofuel feedstock despite a history of soil degradation associated with this crop. We compared soil organic carbon (SOC) storage and microbial communities in Zea mays L. (corn), Panicum virgatum L. (switchgrass), Miscanthus x giganteus Greef et Deuter (miscanthus), and native prairie sites at seven locations that spanned a range of temperatures, precipitation, and soil types in Illinois, USA. By comparing annually harvested switchgrass and miscanthus plots to conventional corn agro-ecosystems and native prairies, we determined the SOC restoration potential of perennial biofuel crops. We also calculated SOC accumulation using the ?13C isotope composition of the soil as a tracer for C4 plant-derived SOC additions. SOC differences among plant species varied significantly among sites, but on average, seven-year-old plots of miscanthus and switchgrass had 73% and 57% greater SOC in the top meter of soil than conventional corn crops, respectively, and had 50-63% greater SOC than the younger (four-year-old) miscanthus and switchgrass plots. The ?13C isotope signature of soil in miscanthus and switchgrass plots also indicated an accumulation of SOC. Plant species and SOC variability among sites explained 40-62% of the variation in microbial communities across sites. Microbial communities associated with annually harvested switchgrass and miscanthus differ from communities found in conventional corn agriculture and prairies. Thus, the potential to restore SOC to agriculturally depleted soils of the Midwest is not dependent on a soil microbial community that mimics prairie soil communities. Planting perennial grasses as biofuel crops can lead to an increase in SOC and a change in soil microbial communities. Conventional agricultural soils might be restored in less than 10 years to SOC levels of undisturbed prairies if miscanthus or switchgrass crops were planted and harvested annually, but this response varies with geographic location.

Davis, S. C.; Yannarell, A.; Masters, M.; Anderson-Teixeira, K.; Drake, J. E.; Darmody, R.; Mackie, R.; David, M.; Delucia, E. H.

2009-12-01

34

Estimation of net greenhouse gas balance using crop- and soil-based approaches: two case studies.  

PubMed

The net greenhouse gas balance (NGHGB), estimated by combining direct and indirect greenhouse gas (GHG) emissions, can reveal whether an agricultural system is a sink or source of GHGs. Currently, two types of methods, referred to here as crop-based and soil-based approaches, are widely used to estimate the NGHGB of agricultural systems on annual and seasonal crop timescales. However, the two approaches may produce contradictory results, and few studies have tested which approach is more reliable. In this study, we examined the two approaches using experimental data from an intercropping trial with straw removal and a tillage trial with straw return. The results of the two approaches provided different views of the two trials. In the intercropping trial, NGHGB estimated by the crop-based approach indicated that monocultured maize (M) was a source of GHGs (-1315 kg CO?(-eq)ha(-1)), whereas maize-soybean intercropping (MS) was a sink (107 kg CO?(-eq)ha(-1)). When estimated by the soil-based approach, both cropping systems were sources (-3410 for M and -2638 kg CO?(-eq)ha(-1) for MS). In the tillage trial, mouldboard ploughing (MP) and rotary tillage (RT) mitigated GHG emissions by 22,451 and 21,500 kg CO?(-eq)ha(-1), respectively, as estimated by the crop-based approach. However, by the soil-based approach, both tillage methods were sources of GHGs: -3533 for MP and -2241 kg CO?(-eq)ha(-1) for RT. The crop-based approach calculates a GHG sink on the basis of the returned crop biomass (and other organic matter input) and estimates considerably more GHG mitigation potential than that calculated from the variations in soil organic carbon storage by the soil-based approach. These results indicate that the crop-based approach estimates higher GHG mitigation benefits compared to the soil-based approach and may overestimate the potential of GHG mitigation in agricultural systems. PMID:23619090

Huang, Jianxiong; Chen, Yuanquan; Sui, Peng; Gao, Wansheng

2013-07-01

35

Factors affecting soil microbial community structure in tomato cropping systems  

Microsoft Academic Search

Soil and rhizosphere microbial communities in agroecosystems may be affected by soil, climate, plant species, and management. The management and environmental factors controlling microbial biomass and community structure were identified in a three-year field experiment. The experiment consisted of a tomato production agroecosystem with the following nine treatments: bare soil, black polyethylene mulch, white polyethylene mulch, vetch cover crop, vetch

Jeffrey S. Buyer; John R. Teasdale; Daniel P. Roberts; Inga A. Zasada; Jude E. Maul

2010-01-01

36

Crop Response to Soil Salinity and Sodicity.  

National Technical Information Service (NTIS)

This report provides the effects of salinity on crop germination, development and yield, nutrient, water, carbohydrate, protein, fat and hormone metabolisms, relative tolerance of crop species/varieties, and also their tolerance at different growth stages...

U. S. Gupta

1975-01-01

37

Influence of cover crops and soil amendments on okra (Abelmoschus esculentus L.) production and soil nematodes  

Microsoft Academic Search

A pot experiment to determine the effects of summer cover crops and soil amendments on okra yields and population densities of various soil nematode taxa was conducted in two consecutive growing seasons in a subtropical region. Two cover crops, sunn hemp (Crotalaria juncea) and sorghum sudangrass (Sorghum bicolorrS. bicolor var. sudanense), were grown and returned to the soil with fallow

Qingren Wang; Yuncong Li; Waldemar Klassen; Zafar Handoo

2007-01-01

38

Mobilization of soil and fertilizer phosphate by cover crops  

Microsoft Academic Search

Incorporation of cover crops into cropping systems may contribute to a more efficient utilization of soil and fertilizer P\\u000a by less P-efficient crops through exudation of P-mobilizing compounds by the roots of P-efficient plant species. The main\\u000a objective of the present work was to test this hypothesis. First a method has been developed which allows the quantification\\u000a of organic anion

Mahmoud Kamh; Walter J. Horst; Fathi Amer; Hamida Mostafa; Peter Maier

1999-01-01

39

Nitrogen Mineralization of Cover Crop Residues in Calcareous Gravelly Soil  

Microsoft Academic Search

Tropical legumes like sunn hemp (Crotolaria juncea L.) and aeschynomene (Aeschynomene evenia L.) have potential as alternative cover crops in tropical regions. The objective of this study was to evaluate the N mineralization rates of three cover crops [aeschynomene (AE), sorghum sudangrass (Sorghum sudanense L.), and sunn hemp (SH)] residues used to amend a calcareous gravelly soil in order to

R. B. Rao; Y. C. Li

2003-01-01

40

Soil Erodibility Parameters Under Various Cropping Systems of Maize  

NASA Astrophysics Data System (ADS)

For four years, runoff and soil loss from seven cropping systems of fodder maize have been measured on experimental plots under natural and simulated rainfall. Besides runoff and soil loss, several variables have also been measured, including rainfall kinetic energy, degree of slaking, surface roughness, aggregate stability, soil moisture content, crop cover, shear strength and topsoil porosity. These variables explain a large part of the variance in measured runoff, soil loss and splash erosion under the various cropping systems. The following conclusions were drawn from the erosion measurements on the experimental plots (these conclusions apply to the spatial level at which the measurements were carried out). (1) Soil tillage after maize harvest strongly reduced surface runoff and soil loss during the winter; sowing of winter rye further reduced winter erosion, though the difference with a merely tilled soil is small. (2) During spring and the growing season, soil loss is reduced strongly if the soil surface is partly covered by plant residues; the presence of plant residue on the surface appeared to be essential in achieving erosion reduction in summer. (3) Soil loss reductions were much higher than runoff reductions; significant runoff reduction is only achieved by the straw system having flat-lying, non-fixed plant residue on the soil surface; the other systems, though effective in reducing soil loss, were not effective in reducing runoff.

van Dijk, P. M.; van der Zijp, M.; Kwaad, F. J. P. M.

1996-08-01

41

Fertiliser induced nitrous oxide emissions during energy crop cultivation on loamy sand soils  

NASA Astrophysics Data System (ADS)

Nitrous oxide (N 2O) fluxes from a loamy sand soil have been collected at an experimental field since 1999. To study the nitrogen (N) fertiliser induced emissions, annual crops and perennial plants received three different levels of N fertilisation: 0, 75, and 150 kg N ha -1. N 2O was measured by gas chromatography and closed chamber technique. Water content of the soil was determined gravimetrically and the soil content of mineral N by ion chromatography. The N 2O fluxes were below 30 ?g N 2O m -2 h -1 during the winter season and varied from 10 to more than 1000 ?g N 2O m -2 h -1 in the course of the vegetation season. N 2O emissions after N fertilisation were assigned to fertiliser induced emissions. High N 2O emissions at the end of the vegetation period are the result of increased mineralisation of soil organic matter. N 2O emissions from freeze-thaw cycles gave only a small contribution to the total annual N 2O emission budget from all blocks studied. Since the mean soil moisture content is very low (10%) and the water-filled pore space (WFPS) correlates negatively with N 2O emissions, nitrification is considered the main source for N 2O emissions. Evaluation of the data regarding dependence on fertilisation level indicates that N 2O fluxes are positively correlated to soil NO 3-N content. The N 2O fluxes from annual crop plots are higher than those from plots with perennial plants (grass, willow, poplar). The mean N 2O-N emission factor for fertiliser induced emissions from tilled soil is 1.0% in contrast to that of non-tilled soil with 0.7%. The mean fertiliser induced N 2O-N emissions, averaged over all crops and the total period of nine years, are in the range of 0.8 ± 0.2% of the N fertiliser applied.

Hellebrand, Hans J.; Scholz, Volkhard; Kern, Jürgen

42

Soil-to-crop transfer factors of tellurium.  

PubMed

Stable tellurium (Te) concentrations in 148 sets of agricultural soil and associated crop samples were measured in this study to obtain soil-to-crop transfer factor (TF) of Te. We used a recently developed simple method that applies digestion of samples with aqua regia and sector field inductively coupled plasma mass spectrometry to measure low Te levels in these samples. Geometric mean (GM) concentrations of Te in soil and crops were 75?gkg(-1)-dry (range: 15-850?gkg(-1)-dry) and 1.8?gkg(-1)-dry (range: 0.1-120?gkg(-1)-dry), respectively; the Te concentration range was significantly wider in crops than in soil. Using these data, we calculated TFs and obtained their range from 1.3×10(-3) to 1.1×10(-1). The GM of TF for upland field crops was calculated to be 2.0×10(-2) and for brown rice was 3.1×10(-2); all crop types had the similar GMs of their TF values. Data comparison for TF of Te was carried out with six elements, which are present in anionic forms in soil environment like Te is, i.e. P, Br, As, Se, Mo, and I. TFs of Te and I showed the highest correlation factor for upland field crops by t-test (r=0.577, p<0.001), but no correlation was found for brown rice. We considered it likely that different water management practices in upland fields and paddy fields affected the Te transfer from soil to crops. PMID:24997965

Yang, Guosheng; Zheng, Jian; Tagami, Keiko; Uchida, Shigeo

2014-09-01

43

Microbial Biomass and Activities in Soil Aggregates Affected by Winter Cover Crops  

Microsoft Academic Search

vegetable cropping systems (Burket et al., 1997); how- ever, it is unclear whether legumes or nonlegumes are Winter cover crops may increase soil organic matter (SOM) and the most suitable for this task. Leguminous winter cover improve soil structure in intensively managed summer vegetable crop- ping systems. Our study examined the influence of three cover crop crops have the potential

I. C. Mendes; A. K. Bandick; R. P. Dick; P. J. Bottomley

1999-01-01

44

Soil Water: Advanced Crop and Soil Science. A Course of Study.  

ERIC Educational Resources Information Center

The course of study represents the fourth of six modules in advanced crop and soil science and introduces the agriculture student to the topic of soil water. Upon completing the three day module, the student will be able to classify water as to its presence in the soil, outline the hydrological cycle, list the ways water is lost from the soil,…

Miller, Larry E.

45

Effect of mixed and single crops on disease suppressiveness of soils  

Microsoft Academic Search

The effect of mixed cropping on disease suppressiveness of soils was tested for two cropping systems, Brussels sprouts¿barley and triticale¿white clover. Disease suppressiveness of field soils was evaluated in bioassays for the soilborne pathogens Rhizoctonia solani, Fusarium oxysporum f. sp. lini, and Gaeumannomyces graminis var. tritici. For both cropping systems, mixed cropping did not enhance disease suppressiveness of the soils.

Gerbert A. Hiddink; Aad J. Termorshuizen; Jos M. Raaijmakers; Bruggen van A. H. C

2005-01-01

46

Winter cover cropping influence on nitrogen mineralization, presidedress soil nitrate test, and corn yields  

Microsoft Academic Search

The mineralization and availability of cover crop N to the succeeding crop are critical components in the management of soil N to reduce N leaching. The effects of several leguminous and non-leguminous cover crops on soil N availability, N mineralization potential, and corn (Zea mays L.) yield were examined. The cover crops had variable effects on soil N availability and

S. Kuo; U. M. Sainju; E. Jellum

1996-01-01

47

Crop residues and soil testing results of samples collected by using different soil samplers on no-tillage system  

Microsoft Academic Search

One of the prominent features of no-till system is the accumulation of crop residues left on the soil surface. Although the technical recommendation for sampling soil for testing purpose states that the crop residues should be removed from the soil surface, it is not feasible when sampling the soil with a geo-referenced hydraulic soil- coring probe. The soil samples may

Pedro Alexandre Varella Escosteguy; Daniel Henkin; Márcio Henkes Caldeira; Jair Pimentel; Adriana Pezarico Arns

2005-01-01

48

Crop Performance and Soil Properties in Two Artificially-Eroded Soils in North-Central Alberta  

SciTech Connect

Field experiments were conducted from 1991 to 1995 at Josephburg (Orthic Black Chernozem, Typic Cryoboroll) and Cooking Lake (Orthic Gray Luvisol, Typic Cryoboralf), Alberta, to determine impact of topsoil removal on selected soil properties, N-mineralization potential and crop yield, and effectiveness of various amendments for restoring the productivity of eroded soils. The simulated-erosion levels were established in the autumn of 1990 by removing 20 cm topsoil in 5-cm depth increments. The four amendments were: control, addition of 5 cm of topsoil, fertilizers to supply 100 kg N ha-1 and 20 kg P ha-1, and cattle manure at 75 Mg ha-1. Topsoil and manure were applied once in the autumn of 1990, while fertilizers were applied annually from 1991 to 1995. Available N and P, total C, N and P, and N-mineralization potential decreased, while bulk density increased with increasing depth of topsoil removal. Tiller number, plant height, spike density, thousand kernel weight, and leaf area index decreased with simulated erosion. Grain yield reductions due to simulated soil erosion were either linear or curvilinear functions of nutrient removal. Application of N and P fertilizers and manure improved grain yield and reduced the impact of yield loss due to erosion. Return of 5 cm of topsoil also increased grain yield, but to a lesser extent than manure or fertilizers. Grain yields were maximized when fertilizers were also applied to organic amendment treatments. In conclusion, the findings suggest the importance of integrated use of organic amendments and chemical fertilizers for best crop yields on severely-eroded soils.

Izaurralde, R Cesar C.; Malhi, S. S.; Nyborg, M.; Solberg, E. D.; Quiroga Jakas, Maria C.

2006-09-01

49

[Effects of different cropping modes on crop root growth, yield, and rhizosphere soil microbes' number].  

PubMed

A multi-year field experiment was conducted to study the variation features of rhizosphere environment and crop root growth under the cropping modes of wheat-soybean (A1), wheat-sweet potato (A2), maize (A3), wheat/maize/soybean (A4), and wheat/maize/sweet potato (A). Among the five modes, A4 increased the plant biomass, root activity, and root dry mass of wheat, maize, and soybean at their flowering and maturing stages, and the quantity of rhizosphere soil bacteria, fungi, and actinomycetes. The biomass and quantity of rhizosphere soil microbes were relay strip intercropping > single cropping, soybean > sweet potato, and fringe row > center row. It was suggested that wheat/maize/soybean relay trip intercropping could improve rhizosphere environment, promote the crops root growth and increase their aboveground biomass, and accordingly, realize yield-increasing. PMID:22489489

Yong, Tai-Wen; Yang, Wen-Yu; Xiang, Da-Bing; Chen, Xiao-Rong

2012-01-01

50

Long-term winter cover cropping effects on corn (Zea mays L.) production and soil nitrogen availability  

Microsoft Academic Search

This study was conducted to determine effects of long-term winter cover cropping with hairy vetch, cereal rye and annual\\u000a ryegrass on soil N availability and corn productivity. From 1987 to 1995, with the exception of the first year of the study,\\u000a the cover crops were seeded each year in late September or early October after the corn harvest and incorporated

S. Kuo; E. J. Jellum

2000-01-01

51

Modified Soil Adjusted Crop Residue Index (MSACRI): a new index for mapping crop residue  

Microsoft Academic Search

The authors present a new index for mapping and estimating the crop residue cover fraction: the MSACRI (Modified Soil Adjusted Crop Residue Index). This index exploits the mid infrared channels: 1.55 ?m to 1.75 ?m and 2.10 ?m to 2.35 ?m. Compared to the visible, these channels are characterized by large transparence in relation to atmospheric constituents. In extreme atmospheric

K. Bannari; D. Haboudane; H. McNairn; F. Bonn

2000-01-01

52

[Use of Remote Sensing for Crop and Soil Analysis  

NASA Technical Reports Server (NTRS)

The primary agricultural objective of this research is to determine what soil and crop information can be verified from remotely sensed images during the growing season. Specifically: (1) Elements of crop stress due to drought, weeds, disease and nutrient deficiencies will be documented with ground truth over specific agricultural sites and (2) Use of remote sensing with GPS and GIS technology for providing a safe and environmentally friendly application of fertilizers and chemicals will be documented.

Johannsen, Chris J.

1997-01-01

53

Herbaceous Energy Crops Program. Annual progress report for FY 1985  

SciTech Connect

This report describes the activities and accomplishments of the Herbaceous Energy Crops Program (HECP) for the year ending September 30, 1985. HECP emphasizes lignocellulosic forage crops. In FY 1985 screening and selection trails began on seven species of perennial and annual grasses and legumes in five projects in the Southeast and the Midwest-Lake State regions. Research also continued on the development of winter rapeseed as a disel-fuel substitute. Activities in FY 1985 included crosses and selections to incorporate atrazine resistance and reduced vernalization requirements in genotypes with desirable seed and oil qualities. Exploratory research efforts in FY 1985 included the physiology and biochemistry of hydrocarbon production in latex bearing plants, the productivity of cattail stands under sustained harvesting, and the development of tissue culture techniques for hard-to-culture sorghum genotypes. Environmental and economic analyses in FY 1985 included completion of a resource assessment of the southwestern United States, a study on successful new crop introductions, and initiation of studies on near-term markets for lignocellulosic energy crops and on vegetable oil extraction facilities. 8 figs., 2 tabs.

Cushman, J.H.; Turhollow, A.F.; Johnston, J.W.

1986-04-01

54

Remote sensing of agricultural crops and soils  

NASA Technical Reports Server (NTRS)

Research in the correlative and noncorrelative approaches to image registration and the spectral estimation of corn canopy phytomass and water content is reported. Scene radiation research results discussed include: corn and soybean LANDSAT MSS classification performance as a function of scene characteristics; estimating crop development stages from MSS data; the interception of photosynthetically active radiation in corn and soybean canopies; costs of measuring leaf area index of corn; LANDSAT spectral inputs to crop models including the use of the greenness index to assess crop stress and the evaluation of MSS data for estimating corn and soybean development stages; field research experiment design data acquisition and preprocessing; and Sun-view angles studies of corn and soybean canopies in support of vegetation canopy reflection modeling.

Bauer, M. E. (principal investigator)

1983-01-01

55

Sunn Hemp: A Cover Crop for Southern and Tropical Farming Systems. Soil Quality-Agronomy Technical Note No. 10.  

National Technical Information Service (NTIS)

Do you want a cover crop that will increase organic matter, provide nitrogen, grow in low fertility sandy soils, and does not harbor nematodes. Sunn hemp (Crotalaria juncea L.) is a legume that when grown as a summer annual can produce over 5,000 pounds o...

1999-01-01

56

Integrated soil-crop system management for food security  

PubMed Central

China and other rapidly developing economies face the dual challenge of substantially increasing yields of cereal grains while at the same time reducing the very substantial environmental impacts of intensive agriculture. We used a model-driven integrated soil–crop system management approach to develop a maize production system that achieved mean maize yields of 13.0 t ha?1 on 66 on-farm experimental plots—nearly twice the yield of current farmers’ practices—with no increase in N fertilizer use. Such integrated soil–crop system management systems represent a priority for agricultural research and implementation, especially in rapidly growing economies.

Chen, Xin-Ping; Cui, Zhen-Ling; Vitousek, Peter M.; Cassman, Kenneth G.; Matson, Pamela A.; Bai, Jin-Shun; Meng, Qing-Feng; Hou, Peng; Yue, Shan-Chao; Romheld, Volker; Zhang, Fu-Suo

2011-01-01

57

A comparison between continuous and controlled grazing on a red duplex soil. II. Subsequent effects on seedbed conditions, crop establishment and growth  

Microsoft Academic Search

The effects of past grazing management practice on subsequent seedbed condition, draft requirements, fuel consumption, crop establishment and growth, and grain yield and quality were examined using three tillage systems on two sowing dates. The crop was wheat (Triticum aestivum), sown on a fragile sandy clay loam (red duplex soil) in a dryland agricultural area (307 mm average annual rainfall)

A. P. B. Proffitt; S. Bendotti; G. P. Riethmuller

1995-01-01

58

Crop Management for Soil Carbon Sequestration  

Microsoft Academic Search

Reducing emissions of greenhouse gases (GHG) from agriculture is related to increasing and protecting soil organic matter (SOM) concentration. Agricultural soils can be a significant sink for atmospheric carbon (C) through increase of the SOM concentration. The natural ecosystems such as forests or prairies, where C gains are in equilibrium with losses, lose a large fraction of the antecedent C

Marek K. Jarecki; Rattan Lal

2003-01-01

59

Chemical Features of Soil: Advanced Crop and Soil Science. A Course of Study.  

ERIC Educational Resources Information Center

The course of study represents the fifth of six modules in advanced crop and soil science and introduces the agriculture student to chemical features of the soil. Upon completing the four day lesson, the student will be able to: (1) list macro- and micro-nutrients, (2) define pH and its effect on plants, (3) outline Cation Exchange of the soil,…

Miller, Larry E.

60

Spectral properties of agricultural crops and soils measured from space, aerial, field, and laboratory sensors  

NASA Technical Reports Server (NTRS)

Investigations of the multispectral reflectance characteristics of crops and soils as measured from laboratory, field, aerial, and satellite sensor systems are reviewed. The relationships of important biological and physical characteristics to the spectral properties of crops and soils are addressed.

Bauer, M. E. (principal investigator); Vanderbilt, V. C.; Robinson, B. F.; Daughtry, C. S. T.

1981-01-01

61

ANIMAL WASTE EFFECTS UPON CROP PRODUCTION, SOIL AND RUNOFF WATERS  

EPA Science Inventory

This investigation was initiated to study the effects of application of differing rates of manure to land on crops, soil, and runoff water. The study was conducted under field conditions in the sub-humid climate of the Northern Great Plains. Manure application rates included leve...

62

Matrices to Revise Crop, Soil, and Environmental Sciences Undergraduate Curricula  

ERIC Educational Resources Information Center

Undergraduate curricula for natural resource and agronomic programs have been introduced and revised during the past several decades with a desire to stay current with emerging issues and technologies relevant to constituents. For the past decade, the Department of Crop, Soil, and Environmental Sciences (CSES) faculty at the University of Arkansas…

Savin, Mary C.; Longer, David; Miller, David M.

2005-01-01

63

Water use efficiency of perennial and annual bioenergy crops in central Illinois  

NASA Astrophysics Data System (ADS)

Sustainable bioenergy production depends upon the efficiency with which crops use available water to produce biomass and store carbon belowground. Therefore, water use efficiency (WUE; productivity vs. annual evapotranspiration, ET) is a key metric of bioenergy crop performance. We evaluate WUE of three potential perennial grass bioenergy crops, Miscanthus × giganteus (miscanthus), Panicum virgatum (switchgrass), and an assemblage of prairie species (28 species), and Zea mays-Glycine max rotation, during the establishment phase in Illinois. Ecosystem WUE (EWUE; net ecosystem productivity vs. ET) was highest in miscanthus, reaching a maximum value of 12.8 ± 0.3 kg ha-1 mm-1 in the third year, followed by switchgrass (7.5 ± 0.3 kg ha-1 mm-1) and prairie (3.9 ± 0.3 kg ha-1 mm-1); the row crop was the lowest. Besides EWUE, harvest-WUE (HWUE, harvested biomass vs. ET) and net biome productivity-WUE (BWUE, calculated as net ecosystem production - harvest vs. ET) were also estimated for all crops and years. After three years of establishment, HWUE and BWUE were highest in miscanthus (9.0 ± 2 and 3.8 ± 2.9 kg ha-1 mm-1, respectively) providing a net benefit to the carbon balance, while the row crops had a negative carbon balance and a negative BWUE. BWUE for maize/soybean indicate that this ecosystem would deplete the soil carbon stocks while using the water resources. Switchgrass had the second highest BWUE, while prairie was almost neutral indicating that long-term carbon sequestration for this agro-ecosystem would be sensitive to harvest timing with an early harvest removing more biomass, and thus carbon, from the field.

Zeri, Marcelo; Hussain, Mir Zaman; Anderson-Teixeira, Kristina J.; Delucia, Evan; Bernacchi, Carl J.

2013-06-01

64

9 - SOIL HYDRAULIC PROPERTIES OF SIEROZEM SOILS AND FIELD CROP OBSERVATIONS FOR RZWQM APPLICATION IN FERGANA  

Microsoft Academic Search

Located in the Aral Sea Basin, Uzbekistan suffers from environmental problems related to soil salinization and water scarcity. Under conditions of limited resources, crop production must be maintained at expense of minimum inputs but aiming the achievement of maximum returns. The search of the best combination between the available resources and crop yield can be eased by the interactive use

G. V. Stulina; M. R. Cameira

65

Effects of soil composition and mineralogy on remote sensing of crop residue cover  

Microsoft Academic Search

The management of crop residues (non-photosynthetic vegetation) in agricultural fields influences soil erosion and soil carbon sequestration. Remote sensing methods can efficiently assess crop residue cover and related tillage intensity over many fields in a region. Although the reflectance spectra of soils and crop residues are often similar in the visible, near infrared, and the lower part of the shortwave

Guy Serbin; Craig S. T. Daughtry; E. Raymond Hunt; James B. Reeves; David J. Brown

2009-01-01

66

Direct drilling of sugar beet ( Beta vulgaris L.) into a cover crop: effects on soil physical conditions and crop establishment  

Microsoft Academic Search

Direct drilling of sugar beet (Beta vulgaris L.) into an autumn sown cover crop may reduce field work in spring and environmental damage, such as soil erosion and nitrate leaching, but the balance of its negative and positive effects on crop establishment is unknown. This study compared the effects of drilling sugar beet directly into a cover crop of wheat

G. Richard; J. Boiffin; Y. Duval

1995-01-01

67

Soil microbial, fungal, and nematode responses to soil fumigation and cover crops under potato production  

Microsoft Academic Search

Sodium N-methyldithiocarbamate (metam sodium) and 1,3 dichloropropene are widely used in potato production for the control of soil-borne\\u000a pathogens, weeds, and plant parasitic nematodes that reduce crop yield and quality. Soil fumigation with metam sodium has\\u000a been shown in microcosm studies to significantly reduce soil microbial populations and important soil processes such as C\\u000a and N mineralization. However, few published

H. P. Collins; A. Alva; R. A. Boydston; R. L. Cochran; P. B. Hamm; A. McGuire; E. Riga

2006-01-01

68

Effect of winter cover crops on soil nitrogen availability, corn yield, and nitrate leaching.  

PubMed

Biculture of nonlegumes and legumes could serve as cover crops for increasing main crop yield, while reducing NO3 leaching. This study, conducted from 1994 to 1999, determined the effect of monocultured cereal rye (Secale cereale L.), annual ryegrass (Lolium multiflorum), and hairy vetch (Vicia villosa), and bicultured rye/vetch and ryegrass/vetch on N availability in soil, corn (Zea mays L.) yield, and NO3-N leaching in a silt loam soil. The field had been in corn and cover crop rotation since 1987. In addition to the cover crop treatments, there were four N fertilizer rates (0, 67, 134, and 201 kg N ha(-1), referred to as N0, N1, N2, and N3, respectively) applied to corn. The experiment was a randomized split-block design with three replications for each treatment. Lysimeters were installed in 1987 at 0.75 m below the soil surface for leachate collection for the N 0, N 2, and N 3 treatments. The result showed that vetch monoculture had the most influence on soil N availability and corn yield, followed by the bicultures. Rye or ryegrass monoculture had either no effect or an adverse effect on corn yield and soil N availability. Leachate NO3-N concentration was highest where vetch cover crop was planted regardless of N rates, which suggests that N mineralization of vetch N continued well into the fall and winter. Leachate NO3-N concentration increased with increasing N fertilizer rates and exceeded the U.S. Environmental Protection Agency's drinking water standard of 10 mg N l(-1) even at recommended N rate for corn in this region (coastal Pacific Northwest). In comparisons of the average NO3-N concentration during the period of high N leaching, monocultured rye and ryegrass or bicultured rye/vetch and ryegrass/vetch very effectively decreased N leaching in 1998 with dry fall weather. The amount of N available for leaching (determined based on the presidedress nitrate test, the amount of N fertilizer applied, and N uptake) correlated well with average NO3-N during the high N leaching period for vetch cover crop treatment and for the control without the cover crops. The correlation, however, failed for other cover crops largely because of variable effectiveness of the cover crops in reducing NO3 leaching during the 5 years of this study. Further research is needed to determine if relay cover crops planted into standing summer crops is a more appropriate approach than fall seeding in this region to gain sufficient growth of the cover crop by fall. Testing with other main crops that have earlier harvest dates than corn is also needed to further validate the effectiveness of the bicultures to increase soil N availability while protecting the water quality. PMID:12805863

Kuo, S; Huang, B; Bembenek, R

2001-10-25

69

Influence of agronomic management of legume crops on soil accumulation with nitrate  

Microsoft Academic Search

Nitrate is known to accumulate under legume crops. The effects of legume crop, inoculation, row width, sowing rate, sowing\\u000a date, and intra-cropping with wheat, on the amount and soil distribution of mineral N, residual soil water, crop biomass and\\u000a crop N were studied at Wagga Wagga in south-east Australia. After removal of most of the above-ground plant material, the\\u000a treatment

Gerard E. O’Connor; Jeffrey Evans; Scott Black; Neil Fettell; Beverley Orchard; Ron Theo

2010-01-01

70

National Crop Loss Assessment Network (NCLAN) 1983 Annual Report.  

National Technical Information Service (NTIS)

The National Crop Loss Assessment Network (NCLAN) consists of a group of organizations cooperating in field work, crop modeling, and economic studies to assess the immediate and long-term consequences of air pollution on crop production. Two primary objec...

W. W. Heck O. C. Taylor R. M. Adams J. E. Miller E. M. Preston

1985-01-01

71

Soil Erosion: Advanced Crop and Soil Science. A Course of Study.  

ERIC Educational Resources Information Center

The course of study represents the last of six modules in advanced crop and soil science and introduces the agriculture student to the topic of soil erosion. Upon completion of the two day lesson, the student will be able to: (1) define conservation, (2) understand how erosion takes place, and (3) list ways of controlling wind and water erosion.…

Miller, Larry E.

72

The short-term cover crops increase soil labile organic carbon in southeastern Australia  

Microsoft Academic Search

Little information is available about the effects of cover crops on soil labile organic carbon (C), especially in Australia.\\u000a In this study, two cover crop species, i.e., wheat and Saia oat, were broadcast-seeded in May 2009 and then crop biomass was\\u000a crimp-rolled onto the soil surface at anthesis in October 2009 in southeastern Australia. Soil and crop residue samples were

Xiaoqi Zhou; Chengrong Chen; Shunbao Lu; Yichao Rui; Hanwen Wu; Zhihong Xu

73

Short-term effects of cover crop incorporation on soil carbon pools and nitrogen availability  

Microsoft Academic Search

Winter cover crops are increasingly used to maintain water quality and\\u000a agoecosystem productivity. Cover crop incorporation influences transient\\u000a soil microbial dynamics and nutrient availability at an early growth\\u000a stage of subsequent crops. Short-term (less than or equal to 35 d)\\u000a effects of cover crop incorporation on soil C pools and N availability\\u000a were evaluated using sandy loam soils from organically

S Hu; NJ Grunwald; AHC vanBruggen; GR Gamble; LE Drinkwater; C Shennan; MW Demment

1997-01-01

74

Soil physical properties, water depletion and crop development under traditional and conservation tillage in southern Spain  

Microsoft Academic Search

Tillage methods affect soil physical properties and, thus, have a direct influence on the replenishment and depletion of soil water storage and crop performance. This study was conducted to determine the effects of traditional and conservation tillage on soil physical properties, soil water replenishment and depletion, and crop development and yield under southern Spanish conditions. The experiments were carried out

F. Moreno; F. Pelegrín; J. E. Fernández; J. M. Murillo

1997-01-01

75

Cover crops enhance soil organic matter, carbon dynamics and microbiological function in a vineyard agroecosystem  

Microsoft Academic Search

Impacts of soil tillage and cover crops on soil carbon (C) dynamics and microbiological function were investigated in a vineyard grown in California's mediterranean climate. We (1) compared soil organic matter (SOM), C dynamics and microbiological activity of two cover crops [Trios 102 (Triticale×Triosecale) (‘Trios’), Merced Rye (Secale cereale) (‘Rye’)] with cultivation (‘Cultivation’) and (2) evaluated seasonal effects of soil

Kerri Steenwerth; K. M. Belina

2008-01-01

76

Effects of agricultural practices of three crops on the soil communities under Mediterranean conditions: field evaluation.  

NASA Astrophysics Data System (ADS)

Sustainable agricultural production relies on soil communities as the main actors in key soil processes necessary to maintain sustainable soil functioning. Soil biodiversity influences soil physical and chemical characteristics and thus the sustainability of crop and agro-ecosystems functioning. Agricultural practices (e.g.: soil tillage, pesticides and fertilizer applications, irrigation) may affects negatively or positively soil biodiversity and abundances by modifying the relationships between organisms in the soil ecosystem. The present study aimed to study the influence of agricultural practices of three crops (potato, onion and maize) under Mediterranean climate conditions on soil macro- and mesofauna during their entire crop cycles. Effects on soil communities were assessed at a higher tier of environmental risk assessment comprising field testing of indigenous edaphic communities in a selected study-site located in a major agriculture region of Central Portugal, Ribatejo e Oeste, neighbouring protected wetlands. A reference site near the agricultural field site was selected as a Control site to compare the terrestrial communities' composition and variation along the crop cycle. The field soil and Control site soil are sandy loam soils. Crops irrigation was performed by center-pivot (automated sprinkler that rotates in a half a circle area) and by sprinklers. Soil macro- and mesofauna were collected at both sites (field and Control) using two methodologies through pitfall trapping and soil sampling. The community of soil macro- and mesofauna of the three crops field varied versus control site along the crops cycles. Main differences were due to arachnids, coleopterans, ants and adult Diptera presence and abundance. The feeding activity of soil fauna between control site and crop areas varied only for potato and onion crops vs. control site but not among crops. Concentration of pesticides residues in soil did not cause apparent negative effects on the soil communities. Significant differences of soil communities from potato and onion crops with the one from control site were observed at the beginning and during the crop cycle, but similarities were observed at the last sampling date after harvesting. The same was observed for the maize crop, indicating that soil communities recovered from the agricultural disturbances associated with crops management. An integrated approach such as the one adopted in present study, taking into consideration soil community's abundances, feeding activity and time variations along entire crop cycles of several crops under Mediterranean conditions, as well as soil exposure to pesticides residues, may contribute to decision making towards a sustainability of crop areas, including pesticide use and management practices.

Leitão, Sara; José Cerejeira, Maria; Abreu, Manuela; Sousa, José Paulo

2014-05-01

77

Measuring and modelling soil evaporation in wheat crops  

NASA Astrophysics Data System (ADS)

Soil evaporation is often an important component of the total water loss from plant canopies, but is poorly estimated in many SVAT models. This paper reports the use of micrometeorological and lysimetric methods to measure soil evaporation ( Es) in the canopy of a wheat crop over a period of 7 weeks as the crop matured and green leaf area index ( L) declined from 3.8 to 0.2. Simultaneous measurements of total canopy evaporation ( E) were made by eddy correlation. The within-canopy micrometeorological methods employed a variance ratio approach and an inverse Lagrangian analysis. The pooled micrometeorological and lysimetric data conformed very well to the relationship {E s}/{E} = exp(-0.61L) with an r2 value of 0.95. The relationship should be a useful empirical means for estimating daily or weekly Es in SVAT studies.

Denmead, O. T.; Dunin, F. X.; Leuning, R.; Raupach, M. R.

1996-05-01

78

Toxicity of naturally-contaminated manganese soil to selected crops.  

PubMed

The impact of manganese excess using naturally contaminated soil (Mn-soil, pseudototal Mn 6494 vs 675 ?g g(-1) DW in control soil) in the shoots of four crops was studied. Mn content decreased in the order Brassica napus > Hordeum vulgare > Zea mays > Triticum aestivum. Growth was strongly depressed just in Brassica (containing 13?696 ?g Mn g(-1) DW). Some essential metals (Zn, Fe) increased in Mn-cultured Brassica and Zea, while macronutrients (K, Ca, Mg) decreased in almost all species. Toxic metals (Ni and Cd) were rather elevated in Mn-soil. Microscopy of ROS, NO, lipid peroxidation, and thiols revealed stimulation in all Mn-cultured crops, but changes were less visible in Triticum, a species with low shoot Mn (2363 ?g g(-1) DW). Antioxidative enzyme activities were typically enhanced in Mn-cultured plants. Soluble phenols increased in Brassica only while proteins rather decreased in response to Mn excess. Inorganic anions (chloride, sulfate, and phosphate) were less accumulated in almost all Mn-cultured crops, while the nitrate level rather increased. Organic anions (malate, citrate, oxalate, acetate, and formate) decreased or remained unaffected in response to Mn-soil culture in Brassica, Hordeum, and Triticum but not in Zea. However, the role of organic acids in Mn uptake in these species is not assumed. Because control and Mn-soil differed in pH (6.5 and 3.7), we further studied its impact on Mn uptake in solution culture (using Mn concentration ?5 mM deducted from water-soluble fraction of Mn-soil). Shoot Mn contents in Mn-treated plants were similar to those observed in soil culture (high in Brassica and low in Triticum) and pH had negligible impact. Fluorescence indicator of "general ROS" revealed no extensive or pH-dependent impact either in control or Mn-cultured roots. Observed toxicity of Mn excess to common crops urges for selection of cultivars with higher tolerance. PMID:24965550

Ková?ik, Jozef; St?rbová, Dagmar; Babula, Petr; Svec, Pavel; Hedbavny, Josef

2014-07-23

79

Spatial Variation of Corn Canopy Temperature as Dependent Upon Soil Texture and Crop Rooting Characteristics.  

National Technical Information Service (NTIS)

A soil plant atmosphere model for corn (Zea mays L.) together with the scaling theory for soil hydraulic heterogeneity are used to study the sensitivity of spatial variation of canopy temperature to field averaged soil texture and crop rooting characteris...

B. J. Choudhury

1983-01-01

80

The partitioning of fertilizer-N between soil and crop: Comparison of ammonium and nitrate applications  

Microsoft Academic Search

Field experiments were carried out in 1987 on winter wheat crops grown on three types of soil. 15N-labelled urea, 15NH4NO3 or NH415NO3 (80 kg N ha-1) was applied at tillering. The soils (chalky soil, hydromorphic loamy soil, sandy clay soil) were chosen to obtain a range of nitrogen dynamics, particularly nitrification. Soil microbial N immobilization and crop N uptake were

Sylvie Recous; J. M. Machet; B. Mary

1992-01-01

81

[Effects of transgenic Bt crops on non-target soil animals].  

PubMed

Transgenic Bt crops are widely planted around the world. With the quick development and extension of genetically modified crops, it is needed to make a deep study on the effects of Bt crops on soil ecosystem. This paper reviewed the research progress on the effects of transgenic Bt crops on the population dynamics and community structure of soil animals, e.g., earthworm, nematode, springtail, mite, and beetle, etc. The development history of Bt crops was introduced, the passway the Bt protein comes into soil as well as the residual and degradation of Bt protein in soil were analyzed, and the critical research fields about the ecological risk analysis of transgenic Bt crops on non-target soil animals in the future were approached, which would provide a reference for the research of the effects of transgenic Bt crops on non-target soil animals. PMID:20707123

Yuan, Yi-gang; Ge, Feng

2010-05-01

82

The effects of cover crops on soil physical properties and nutrient cycling  

Microsoft Academic Search

Cover crops improve soil aggregate stability, increase water infiltration, and legume cover crops also fix nitrogen and scavenge nutrients that are subject to leaching. Greenhouse and field experiments were conducted in Indiana to measure growth of different cover crops and their effects on soil properties. The objective of the greenhouse experiment was to study the response of three varieties of

Mohammad Zaman Amini

2011-01-01

83

Using a basin-scale hydrological model to estimate crop transpiration and soil evaporation  

Microsoft Academic Search

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

G. Kite

2000-01-01

84

Ruminant Grazing of Cover Crops: Effects on Soil Properties and Agricultural Production  

ERIC Educational Resources Information Center

Integrating livestock into a cropping system by allowing ruminant animals to graze cover crops may yield economic and environmental benefits. The effects of grazing on soil physical properties, soil organic matter, nitrogen cycling and agricultural production are presented in this literature review. The review found that grazing cover crops

Poffenbarger, Hanna

2010-01-01

85

Phosphorus accumulation in cultivated soils from long-term annual applications of cattle feedlot manure.  

PubMed

Historically, manure has been recognized as an excellent soil amendment that can improve soil quality and provide nutrients for crop production. In areas of high animal density, however, the potential for water pollution resulting from improper storage or disposal of manure may be significant. The objective of this study was to determine the P balance of cultivated soils under barley (Hordeum vulgare L.) production that have received long-term annual manure amendments. Nonirrigated soils at the study site in Lethbridge, AB, Canada, have received 0, 30, 60, or 90 Mg manure ha(-1) (wet wt. basis) while irrigated plots received 0, 60, 120, and 180 Mg ha(-1) annually for 16 yr. The amount of P removed in barley grain and straw during the 16-yr period was between 5 and 18% of the cumulative manure P applied. There was a balance between P applied in manure and P recovered in crops and soils (to the 150-cm depth) of nonirrigated plots during the 16-yr study. In irrigated plots, as much as 1.4 Mg P ha(-1) added (180 Mg ha(-1) yr(-1) treatment) was not recovered over 16 yr, and was probably lost through leaching. The risk of ground water contamination with P from manure was greater in irrigated than nonirrigated plots that have received long-term annual manure amendments. Manure application rates should be reduced in nonirrigated and irrigated plots to more closely match manure P inputs to crop P requirements. PMID:11215658

Whalen, J K; Chang, C

2001-01-01

86

Crop residues as soil amendments and feedstock for bioethanol production.  

PubMed

Traditional solid fuels account for more than 90% of the energy supply for 3 billion people in developing countries. However, liquid biofuels (e.g., ethanol) are perceived as an important alternative to fossil fuel. Global crop residue production is estimated at about 4 billion Mg for all crops and 3 billion Mg per annum for lignocellulosic residues of cereals. One Mg of corn stover can produce 280L of ethanol, compared with 400L from 1Mg of corn grains; 1Mg of biomass is also equivalent to 18.5GJ of energy. Thus, 3 billion Mg of residues are equivalent to 840 billion L of ethanol or 56x10(9)GJ of energy. However, removal of crop residues exacerbates soil degradation, increases net emission of CO2, and aggravates food insecurity. Increasing the SOC pool by 1 Mg C ha(-1)yr(-1) through residue retention on soil can increase world food grain production by 24-40 million Mg yr(-1), and root/tuber production by 6-11 million Mg yr(-1). Thus, identifying alternate sources of biofuel feedstock (e.g., biofuel plantations, animal waste, municipal sold waste) is a high priority. Establishing biofuel plantations on agriculturally marginal or degraded lands can off-set 3.5-4 Pg Cyr(-1). PMID:18053700

Lal, R

2008-01-01

87

Effects of irrigation on crops and soils with Raft River geothermal water  

SciTech Connect

The Raft River Irrigation Experiment investigated the suitability of using energy-expended geothermal water for irrigation of selected field-grown crops. Crop and soil behavior on plots sprinkled or surface irrigated with geothermal water was compared to crop and soil behavior on plots receiving water from shallow irrigation wells and the Raft River. In addition, selected crops were produced, using both geothermal irrigation water and special management techniques. Crops irrigated with geothermal water exhibited growth rates, yields, and nutritional values similar to comparison crops. Cereal grains and surface-irrigated forage crops did not exhibit elevated fluoride levels or accumulations of heavy metals. However, forage crops sprinkled with geothermal water did accumulate fluorides, and leaching experiments indicate that new soils receiving geothermal water may experience increased salinity, exchangeable sodium, and decreased permeability. Soil productivity may be maintained by leaching irrigations.

Stanley, N.E.; Schmitt, R.C.

1980-01-01

88

Soil survey versus crop production as a measure of soil productivity: Soil-strength effects on row-crop yields. Final report  

SciTech Connect

The objective of the study was to examine the use of a recording cone penetrometer as a predictor of crop yield for constructed soils. State-of-the-art reclaimed land in Illinois is capable of producing good corn and soybean yields. Previous research has examined observable features of constructed soils ranging from those which are highly drought sensitive to those which are highly productive for causes of the observed crop performance differences. The studies have made it increasingly evident that poor soil physical condition is the major factor limiting row crop productivity following surface mining in Illinois. Efforts to build significant yield prediction models based on penetrometer data were successful. Too much yield variation remained unaccounted for to use these models alone to predict productivity of reclaimed land for reclamation law enforcement.

Jansen, I.J.; Vance, S.L.; Walker, W.M.

1985-12-30

89

Quantification of compaction effects on soil physical properties and crop growth  

Microsoft Academic Search

A quantitative description of soil compaction effects is required to improve soil management for reducing compaction problems in crop production and environment. Our objective is to provide a review of indices and methods used to quantify the effects of compaction on soil physical properties and crop growth. The paper starts with the description of available methods to quantify stress and

J. Lipiec; R. Hatano

2003-01-01

90

Soil macrofauna affect crop nitrogen and water use efficiencies in semi-arid West Africa  

Microsoft Academic Search

It is increasingly recognised that soil fauna have a significant role in soil processes affecting nutrient availability and crop performance. A field experiment was conducted in southern Burkina Faso (West Africa) to investigate the contribution of soil fauna to nutrient availability and crop performance after application of different organic materials with contrasting qualities. A split plot design with four replications

E. Ouédraogo; A. Mando; L. Brussaard

2006-01-01

91

Summer cover crops and soil amendments to improve growth and nutrient uptake of okra  

SciTech Connect

A pot experiment with summer cover crops and soil amendments was conducted in two consecutive years to elucidate the effects of these cover crops and soil amendments on 'Clemson Spineless 80' okra (Abelmoschus esculentus) yields and biomass production, and the uptake and distribution of soil nutrients and trace elements. The cover crops were sunn hemp (Crotalaria juncea), cowpea (Vigna unguiculata), velvetbean (Mucuna deeringiana), and sorghum sudan-grass (Sorghum bicolor x S. bicolor var. sudanense) with fallow as the control. The organic soil amendments were biosolids (sediment from wastewater plants), N-Viro Soil (a mixture of biosolids and coal ash), coal ash (a combustion by-product from power plants), co-compost (a mixture of 3 biosolids: 7 yard waste), and yard waste compost (mainly from leaves and branches of trees and shrubs, and grass clippings) with a soil-incorporated cover crop as the control. As a subsequent vegetable crop, okra was grown after the cover crops, alone or together with the organic soil amendments, had been incorporated. All of the cover crops, except sorghum sudangrass in 2002-03, significantly improved okra fruit yields and the total biomass production. Both cover crops and soil amendments can substantially improve nutrient uptake and distribution. The results suggest that cover crops and appropriate amounts of soil amendments can be used to improve soil fertility and okra yield without adverse environmental effects or risk of contamination of the fruit. Further field studies will be required to confirm these findings.

Wang, Q.R.; Li, Y.C.; Klassen, W. [University of Florida, Homestead, FL (United States). Center for Tropical Research & Education

2006-04-15

92

NATIONAL CROP LOSS ASSESSMENT NETWORK (NCLAN) 1981 ANNUAL REPORT  

EPA Science Inventory

The National Crop Loss Assessment Network (NCLAN) consists of a group of cooperating organizations engaged in field work, crop modeling, and economic studies to assess the immediate and long-term economic consequences of the effects of air pollution on crop production. The progra...

93

NATIONAL CROP LOSS ASSESSMENT NETWORK (NCLAN) 1985 ANNUAL REPORT  

EPA Science Inventory

The National Crop Loss Assessment Network (NCLAN) consists of a group of organizations cooperating in field work, crop modeling, and economic studies to assess the immediate and long-term economic consequences of air pollution on crop production. Two primary objectives are (1) to...

94

NATIONAL CROP LOSS ASSESSMENT NETWORK (NCLAN) 1983 ANNUAL REPORT  

EPA Science Inventory

The National Crop Loss Assessment Network (NCLAN) consists of a group of organizations cooperating in field work, crop modeling, and economic studies to assess the immediate and long-term consequences of air pollution on crop production. Two primary objectives are (1) to define r...

95

Agroforestry systems and soil surface management of a tropical alfisol: I: Soil moisture and crop yields  

Microsoft Academic Search

Field experiments were conducted on a tropical Alfisol at Ibadan, Nigeria, to evaluate the effects on soil moisture and crop yields of three agroforestry systems. Effects of agroforestry treatments involving two perennial shrubs (Leucaena leucocephala and Gliricidia sepium), each at 2-m and 4-m row spacings, were compared with no-till and plow-till systems of seedbed preparation. Measurements were made for soil

R. Lal

1989-01-01

96

Productivity of annual cropping and agroforestry systems on a shallow Alfisol in semi-arid India  

Microsoft Academic Search

An experiment was conducted at ICRISAT Center, Patancheru, India from June 1984 to April 1988 on a shallow Alfisol to determine whether the productivity of annual\\u000a crop systems can be improved by adding perennial species such as Leucaena leucocephala managed as hedgerows. Except in the first year, crop yields were suppressed by Leucaena due to competition for moisture. The severity

M. R. Rao; C. K. Ong; P. Pathak; M. M. Sharma

1991-01-01

97

C and N accumulations in soil aggregates determine nitrous oxide emissions from cover crop treated rice paddy soils during fallow season.  

PubMed

Combination of leguminous and non-leguminous plant residues are preferably applied in rice paddy soils to increase the rate of organic matter mineralization and to improve plant growth. However, organic matter addition facilitates methane (CH4) emission from rice paddy soil. Mineralization of organic nitrogen (N) increases NO3-N concentrations in soil, which are precursors for the formation of nitrous oxide (N2O). However, N2O is a minor greenhouse gas emitted from submerged rice field and hence is not often considered during calculation of total global warming potential (GWP) during rice cultivation. The hypothesis of this study was that fluxes of N2O emissions might be changed after removal of flooded water from rice field and the effect of cover crops on N2O emissions in the fallow season might be interesting. However, the effects of N-rich plant residues on N2O emission rates in the fallow season and its effect on annual GWP were not studied before. In this experiment, combination of barley (non-leguminous) and hairy vetch (leguminous) biomasses were applied at 9Mgha(-1) and 27Mgha(-1) rates in rice paddy soil. Cover crop application significantly increased CH4 emission flux while decreased N2O emissions during rice cultivation. The lowest N2O emission was observed in 27Mgha(-1) cover crop treated plots. Cover crop applications increased N contents in soil aggregates especially in smaller aggregates (<250?m), and that proportionately increased the N2O emission potentials of these soil aggregates. Fluxes of N2O emissions in the fallow season were influenced by the N2O emission potentials of soil aggregates and followed opposite trends as those observed during rice cultivation. Therefore, it could be concluded that the doses of cover crop applications for rice cultivation should not be optimized considering only CH4, but N2O should also be considered especially for fallow season to calculate total GWP. PMID:24880551

Pramanik, Prabhat; Haque, Md Mozammel; Kim, Sang Yoon; Kim, Pil Joo

2014-08-15

98

Effects of Continuous Cropping of Rye on Soil Biota and Biochemistry  

Microsoft Academic Search

Long-term studies on the ecological effects of continuous rye cultivations carried out in Poland are summarized. It was shown that in continuous cropping of rye, despite the decrease of crop yields, no significant difference was observed in annual primary production rates compared with estimates found for rye fields cultivated in diversified crop rotation patterns. In continuous cultivation of rye fauna

Lech Ryszkowski; Lech Szajdak; Jerzy Karg

1998-01-01

99

Separating soil evaporation and crop transpiration to improve crop water use efficiency  

NASA Astrophysics Data System (ADS)

A network of a FAO/IAEA Coordinated Research Project (CRP) on "Managing Irrigation Water to Enhance Crop Productivity under Water-Limiting Conditions: A Role for Isotopic Techniques", involving seven countries was implemented from 2007 to 2012, to identify approaches to improve crop water productivity (production per unit of water input) under water-limiting conditions using isotopic and related techniques. This paper presents findings from the two of the studied sites, one in China and another in Morocco, in using both isotopic and conventional techniques to separate soil evaporation (E) and crop transpiration (T) from total water losses in evapotranspiration (ET) for winter wheat grown under different climatic conditions and methods of irrigation management practices. In the North China Plain (NCP), the estimated E/ET of winter wheat by the isotopic method (Keeling plot using delta oxygen-18 (?18O)) was in agreement with that obtained by conventional methods (eddy covariance and micro-lysimeter). The high correlation between these methods (R2=0.85, n=27) showed that the E from wheat-growing field contributes an average of 30% of water losses for the whole growing season (Nov-June), with higher E percentage (68%) can be expected before elongation stage due to incomplete canopy cover. The results also showed that through deficit irrigation and improved irrigation scheduling, soil E losses could be reduced by 10-30% of the total water loss compared with full irrigation. In Morocco, field Keeling plot isotopic E and T separation study was carried out for two days in spring of 2012 at Sidi Rahal. The percentage contribution of T to total ET was approximately 73%. The experimental results obtained from both China and Moroccan sites were used to validate FAO's AquaCrop model for E and T, and for improving irrigation scheduling and agronomic practices. Good correlation (R2=0.83) was obtained between measured (isotopic) and AquaCrop simulated ET from NCP. The measured and simulated E and T results from Morocco also compared well; the difference in E between the two approaches was only 5-12% over the two-day study.

Heng, Lee; Nguyen, Long; Gong, Daozhi; Mei, Xurong; Amenzou, Noureddine

2014-05-01

100

A comparison of the carbon dioxide fluxes of two annual cropping systems and a perennial hay field in southern Manitoba over 30 months  

NASA Astrophysics Data System (ADS)

The eddy-covariance method was used to measure net ecosystem productivity over three adjacent fields from 2009 to 2011: two annual cropping systems (oat-canola-oat and hay-oat-fallow) recently converted from perennial cropping, and a perennial hay/pasture. We compared the management practises, determined the net carbon budget, and examined the effects of inter-annual variability. Carbon accumulation began earlier in the spring and continued later in the fall at the perennial site, compared with the annual crop sites, due to a longer growing season and continual plant cover. Cumulative cropping season net ecosystem productivity at the perennial site ranged from 40 to 240 g C m-2 because of variable weather. Including harvest removals and manure additions, the perennial site gained 120 g carbon m-2 and the annual sites lost 240 and 415 g carbon m-2, respectively, over the 30-month period. This indicates that the annual cropping systems would decrease soil carbon at this location.

Taylor, Amanda M.

101

[Soil and water loss from cultivated slope land derived from granite under different cropping systems in Three-Gorges reservoir areas].  

PubMed

The water and soil loss caused by cultivation on slope land derived from granite under different cropping systems in the Three-Gorges reservoir area was analyzed based on the data from localized observation. The results showed that in this area, proximately 60% of total annual rainfall, distributed in May to August, and 60% of soil erosion occurred in these four months, with 50% in June and July. The coverage rates under different cropping systems differed significantly, e.g., triple-cropping systems and inter-croping system with perennial plants (grass and day lily) had a bigger covering than double-cropping systems. The soil loss under cropping system with peanut was much lower than that with sweet potato, because the covering rate of the former was higher than that of the latter in summer raining season. The sequence of soil and nutrient loss for different cropping systems was rape (wheat) sweet potato > rape(wheat)/corn/sweet potato > rape(wheat)/corn/peanut/rape(wheat)/grass/peanut/rape(wheat)/day lily/peanut. It was concluded that soil loss from cultivated slope land could be controlled below a permissible value, if rational cropping and management systems were adopted. PMID:11813432

Xiang, W; Liang, C; Li, W

2001-02-01

102

Interaction between soil mineralogy and the application of crop residues on aggregate stability and hydraulic conductivity of the soil  

NASA Astrophysics Data System (ADS)

One of the main goals of modern agriculture is to achieve sustainability by maintaining crop productivity while avoiding soil degradation. Intensive cultivation could lead to a reduction in soil organic matter that could affect the structure stability and hydraulic conductivity of the soil. Moreover, crops extract nutrients from the soil that are taken away from the field when harvested, and as a consequence, the addition of fertilizers to the soil is necessary to maintain crop productivity. One way to deal with these problems is to incorporate crop residues into the soil after harvest. Crop residues are a source of organic matter that could improve soil physical properties, such as aggregate stability and soil hydraulic conductivity. However, this effect could vary according to other soil properties, such as clay content, clay mineralogy, and the presence of other cementing materials in the soil (mainly carbonates and aluminum and iron oxides). In the present work, the interaction between the addition of chickpea crop residues to the soil and clay mineralogy on aggregate stability and saturated hydraulic conductivity were studied. Chickpea plant residues were added at a rate of 0.5% (w/w) to smectitic, kaolinitic, illitic and non-phyllosilicate soils from different regions. The soils without (control) and with chickpea residues were incubated for 0, 3, 7 and 30 days, and the saturated hydraulic conductivity of the soils was measured in columns after each incubation time. The response of hydraulic conductivity to the addition of residues and incubation time was different in the soils with various mineralogies, although in general, the addition of chickpea residues increased the saturated hydraulic conductivity as compared with the control soils. This positive effect of crop residues on hydraulic conductivity was mainly a result of improved aggregate stability and resistance to slaking during wetting.

Lado, M.; Kiptoon, R.; Bar-Tal, A.; Wakindiki, I. I. C.; Ben-Hur, M.

2012-04-01

103

Influence of Soil Tillage Systems on Soil Respiration and Production on Wheat, Maize and Soybean Crop  

NASA Astrophysics Data System (ADS)

Soil respiration leads to CO2 emissions from soil to the atmosphere, in significant amounts for the global carbon cycle. Soil capacity to produce CO2 varies depending on soil, season, intensity and quality of agrotechnical tillage, soil water, cultivated plant, fertilizer etc. The data presented in this paper were obtained on argic-stagnic Faeoziom (SRTS, 2003). These areas were was our research, presents a medium multiannual temperature of 8.20C, medium of multiannual rain drowns: 613 mm. The experimental variants chosen were: A. Conventional system (CS): V1-reversible plough (22-25 cm)+rotary grape (8-10 cm); B. Minimum tillage system (MT): V2 - paraplow (18-22 cm) + rotary grape (8-10 cm); V3 - chisel (18-22 cm) + rotary grape (8-10 cm);V4 - rotary grape (10-12 cm); C. No-Tillage systems (NT): V5 - direct sowing. The experimental design was a split-plot design with three replications. In one variant the area of a plot was 300 m2. The experimental variants were studied in the 3 years crop rotation: maize - soy-bean - autumn wheat. To soil respiration under different tillage practices, determinations were made for each crop in four vegetative stages (spring, 5-6 leaves, bean forming, harvest) using ACE Automated Soil CO2 Exchange System. Soil respiration varies throughout the year for all three crops of rotation, with a maximum in late spring (1383 to 2480 mmoli m-2s-1) and another in fall (2141 to 2350 mmoli m-2s-1). The determinations confirm the effect of soil tillage system on soil respiration, the daily average is lower at NT (315-1914 mmoli m-2s-1), followed by MT (318-2395 mmoli m-2s-1) and is higher in the CS (321-2480 mmol m-2s-1). Productions obtained at MT and NT don't have significant differences at wheat and are higher at soybean. The differences in crop yields are recorded at maize and can be a direct consequence of loosening, mineralization and intensive mobilization of soil fertility. Acknowledgments: This work was supported by CNCSIS-UEFISCSU, project number PN II-RU 273/2010.

Moraru, P. I.; Rusu, T.

2012-04-01

104

Cover crop effects on the fate of N following soil application of swine manure  

Microsoft Academic Search

Cereal grain cover crops increase surface cover, anchor corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] residues, increase infiltration, reduce both rill and interrill erosion, scavenge excess nutrients from the soil, and are easily obtained and inexpensive compared to other cover crop options. The use of cereal grain cover crops in fields where manure application occurs should increase

T. B. Parkin; T. C. Kaspar; J. W. Singer

2006-01-01

105

Simulation of Hail and Soil Type Effects on Crop Yield Losses in Kansas, USA  

Microsoft Academic Search

Computer simulation was used for predictive analysis of the effects of weather and soil type on crop yield in the U.S. crop insurance program. The Environmental Policy Integrated Climate (EPIC) model was modified to include hail weather events, which completed the modifications necessary to simulate the four most frequent causes of crop yield loss (hail, excessive wet, excessive cold, and

Er-Da WANG; B. B. LITTLE; J. A. WILLIAMS; Yang YU; M. SCHUCKING

2009-01-01

106

Crop responses to compacted soil: capture and efficiency in the use of water and radiation  

Microsoft Academic Search

We combined field and modelling experiments to investigate crop-level responses to soil compaction. Our working hypotheses are that the effect of soil compaction on crop growth is (i) primarily mediated by reduction in capture of water and photosynthetically active radiation (PAR), and (ii) secondarily affected by reduced transpiration efficiency (biomass per unit transpiration) and radiation-use efficiency (biomass per unit intercepted

Víctor O. Sadras; Garry J. O’Leary; David K. Roget

2005-01-01

107

Soil Organic Carbon Sequestration Rates by Tillage and Crop Rotation: A Global Data Analysis  

Microsoft Academic Search

tices include, but are not limited to, reducing tillage intensity, decreasing or ceasing the fallow period, using Changes in agricultural management can potentially increase the a winter cover crop, changing from monoculture to rota- accumulation rate of soil organic C (SOC), thereby sequestering CO2 from the atmosphere. This study was conducted to quantify potential tion cropping, or altering soil inputs

Tristram O. West; Wilfred M. Post

2002-01-01

108

Cover crop effect on soil carbon fractions under conservation tillage cotton  

Microsoft Academic Search

Cover crops may influence soil carbon (C) sequestration and microbial biomass and activities by providing additional residue C to soil. We examined the influence of legume [crimson clover (Trifolium incarnatum L.)], nonlegume [rye (Secale cereale L.)], blend [a mixture of legumes containing balansa clover (Trifolium michelianum Savi), hairy vetch (Vicia villosa Roth), and crimson clover], and rye+blend mixture cover crops

Upendra M. Sainju; Harry H. Schomberg; Bharat P. Singh; Wayne F. Whitehead; P. Glynn Tillman; Sharon L. Lachnicht-Weyers

2007-01-01

109

Cover crop and tillage effects on soil enzyme activities following tomato  

Microsoft Academic Search

Increasing numbers of vegetable growers are adopting conservation tillage practices and including cover crops into crop rotations. The practice helps to increase or maintain an adequate level of soil organic matter and improves vegetable yields. The effects of the practices, however, on enzyme activities in southeastern soils of the United States have not been well documented. Thus, the objectives of

Said A. Hamido; K. Kpomblekou-A

2009-01-01

110

Developing a Foundation for Constructing New Curricula in Soil, Crop, and Turfgrass Sciences  

ERIC Educational Resources Information Center

Some soil and crop science university programs undergo curricula revision to maintain relevancy with their profession and/or to attract the best students to such programs. The Department of Soil and Crop Sciences at Texas A&M University completed a thorough data gathering process as part of its revision of the undergraduate curriculum and degree…

Jarvis, Holly D.; Collett, Ryan; Wingenbach, Gary; Heilman, James L.; Fowler, Debra

2012-01-01

111

Soil Carbon and Nitrogen Changes in Long-Term Continuous Lowland Rice Cropping  

Microsoft Academic Search

Rice (Oryza sativa L.), the main staple food in Asia, is typically produced on submerged anaerobic soils, which generally have slower decomposition of soil organic matter (SOM) than aerobic soils. We sampled four long-term experiments in the Philippines, with two or three rice crops grown each year with continuous or near-continuous soil submergence, to determine the effect of fertil- izer

Mirasol F. Pampolino; Eufrocino V. Laureles; Hermenegildo C. Gines; Roland J. Buresh

2008-01-01

112

Temporal stability of soil moisture in irrigated carrot crops in Northeast Brazil  

Microsoft Academic Search

Soil water content plays an important role on crop productivity, mainly in the semiarid zones of the world. Given the importance of water resources to agricultural systems, investigations of soil moisture spatio-temporal variability can contribute to soil management, especially at highly heterogeneous irrigated soils occurring in alluvial valleys of the Brazilian northeast. In this sense, techniques which allow identifying and

Edivan Rodrigues de Souza; Suzana Maria Gico Montenegro

2011-01-01

113

Soil nitrous oxide emissions in long-term cover crops-based rotations under subtropical climate  

Microsoft Academic Search

It has been shown that cover crops can enhance soil nitrous oxide (N2O) emissions, but the magnitude of increase depends on the quantity and quality of the crop residues. Therefore, this study aimed to evaluate the effect of long-term (19 and 21 years) no-till maize crop rotations including grass [black oat (Avena strigosa Schreb)] and legume cover crops [vetch (Vigna

Juliana Gomes; Cimélio Bayer; Falberni de Souza Costa; Marisa de Cássia Piccolo; Josiléia Acordi Zanatta; Frederico Costa Beber Vieira; Johan Six

2009-01-01

114

Crop residue management to reduce erosion and improve soil quality: Northern Great plains. Conservation research report  

SciTech Connect

This publication summarizes research and experience that show the potential benefits and problems related to decreasing tillage and leaving more residues on the soil surface. Experts discuss the equipment, management practices, crop protection chemicals, crop rotations, cover crops, and cropping systems that will enable farmers to control erosion on their lands-so they are in Federal conservation compliance-while simultaneously optimizing their net returns and improving the environment and natural resources.

Moldenhauer, W.C.; Black, A.L.

1994-09-01

115

Short Rotation Woody Crops Program. Annual Progress Report for 1985.  

National Technical Information Service (NTIS)

This report describes the technical progress and accomplishments in the Short Rotation Woody Crops Program (SRWCP) for the year ending September 30, 1985. The SRWCP is sponsored by the US Department of Energy's Biofuels and Municipal Waste Technology Divi...

J. W. Ranney J. L. Trimble L. L. Wright P. A. Layton R. D. Perlack

1986-01-01

116

Herbaceous energy crops program: Annual progress report for FY 1987  

SciTech Connect

This report describes the activities and accomplishments of the Herbaceous Energy Crops Program (HECP) for the year ending September 30, 1987. The HECP is one of three research programs on the production of biomass energy crops supported by the US Department of Energy's Biofuels and Municipal Waste Technology Division. It is devoted to research on the development of terrestrial, nonwoody plant species for use as energy feedstocks. Oak Ridge National Laboratory provides field management for the HECP and has overall responsibility for its research. The HECP focuses on the types of crops that appear most promising for producing fuels or feedstocks for fuels. The research program emphasizes lignocellulosic energy crops as feedstocks for biochemical and thermochemical conversion to liquid and gaseous fuels. In FY 1987 screening and selection trials continued for a third year at five institutions in the Southeast and Midwest/Lake States, and two new projects were initiated in the Great Plains. 18 refs., 7 figs., 15 tabs.

Cushman, J.H.; Turhollow, A.F.; Johnston, J.W.

1989-01-01

117

Does agricultural crop diversity enhance soil microbial biomass and organic matter dynamics? A meta-analysis.  

PubMed

Our increasing dependence on a small number of agricultural crops, such as corn, is leading to reductions in agricultural biodiversity. Reductions in the number of crops in rotation or the replacement of rotations by monocultures are responsible for this loss of biodiversity. The belowground implications of simplifying agricultural plant communities remain unresolved; however, agroecosystem sustainability will be severely compromised if reductions in biodiversity reduce soil C and N concentrations, alter microbial communities, and degrade soil ecosystem functions as reported in natural communities. We conducted a meta-analysis of 122 studies to examine crop rotation effects on total soil C and N concentrations, and the faster cycling microbial biomass C and N pools that play key roles in soil nutrient cycling and physical processes such as aggregate formation. We specifically examined how rotation crop type and management practices influence C and N dynamics in different climates and soil types. We found that adding one or more crops in rotation to a monoculture increased total soil C by 3.6% and total N by 5.3%, but when rotations included a cover crop (i.e., crops that are not harvested but produced to enrich the soil and capture inorganic N), total C increased by 8.5% and total N 12.8%. Rotations substantially increased the soil microbial biomass C (20.7%) and N (26.1%) pools, and these overwhelming effects on microbial biomass were not moderated by crop type or management practices. Crop rotations, especially those that include cover crops, sustain soil quality and productivity by enhancing soil C, N, and microbial biomass, making them a cornerstone for sustainable agroecosystems. PMID:24834741

McDaniel, M D; Tiemann, L K; Grandy, A S

2014-04-01

118

Carbon mineralization in the soils under different cover crops and residue management in an intensive protected vegetable cultivation  

Microsoft Academic Search

Continuous cropping under plastic greenhouses, a common practice in intensive Chinese vegetable production systems, has led to the decline of soil productivity and crop yields. A 4-year greenhouse experiment on cucumber double-cropping systems was conducted in Changping country, Beijing, China, to investigate the effects of summer cover crops and residue management on soil microbial biomass carbon (MBC), C mineralization and

Yongqiang Tian; Juan Liu; Xuhui Wang; Lihong Gao

2011-01-01

119

Carbon and N mineralization as affected by soil cultivation and crop residue in a calcareous wetland ecosystem in Central Iran  

Microsoft Academic Search

Mineralization of soil organic matter plays a key role in supplying nutrient elements essential to plant growth. Soil cultivation and crop residue affect C mineralization and nutrient availability in wetland ecosystems. This study evaluated the combined impacts of soil cultivation and crop residue on C and N mineralization in a calcareous wetland soil (Luvic Calcisol) in Central Iran. Soil samples

Fayez Raiesi

2006-01-01

120

No-tillage, crop residue additions, and legume cover cropping effects on soil quality characteristics under maize in Patzcuaro watershed (Mexico)  

Microsoft Academic Search

Intensive maize (Zea mays L.) cropping based on conventional tillage practices has resulted in soil quality degradation in the Patzcuaro Watershed in central Mexico. A field experiment with seven soil management treatments was implemented on a sandy loam Andisol to evaluate the impact on soil quality of maize cropping with conventional tillage, no-tillage with varying percentages of surface residue coverage

A. Roldán; F. Caravaca; M. T. Hernández; C. Garc??a; C. Sánchez-Brito; M. Velásquez; M. Tiscareño

2003-01-01

121

Changes of Soil Microbial Biomass Carbon and Nitrogen with Cover Crops and Irrigation in a Tomato Field  

Microsoft Academic Search

In order to understand how soil microbial biomass was influenced by incorporated residues of summer cover crops and by water regimes, soil microbial biomass carbon (C) and nitrogen (N) were investigated in tomato field plots in which three leguminous and a non-leguminous cover crop had been grown and incorporated into the soil. The cover crops were sunn hemp (Crotalaria juncea

Q. R. Wang; Y. C. Li; W. Klassen

2007-01-01

122

SOIL ECOLOGICAL AND ECONOMIC EVALUATION OF GENETICALLY MODIFIED CROPS - ECOGEN Hierarchical classification of environmental factors and agricultural practices affecting soil fauna under cropping systems using Bt maize  

Microsoft Academic Search

Summary The population dynamics of soil organisms under agricultural field conditions are influenced by many factors, such as pedology and climate, but also farming practices such as crop type, tillage and the use of pesticides. To assess the real effects of farming practices on soil organisms it is necessary to rank the influence of all of these parameters. Bt maize

Marko Debeljaka; Paul H. Kroghd; Saso Dzeroskia; Batiment Villemin

123

COTORAN WASH-OFF FROM COVER CROP RESIDUES AND DEGRADATION IN GIGGER SOIL  

Microsoft Academic Search

Cover crop residues on no-till soil will intercept a portion of applied herbicides. Thus, herbicide efficacy in no-till systems depends,in part, on rainfall to wash the herbicide onto the soil. Tillage and cover crop residue may also influence degradation of a herbicide in soil. This series of studies examined Cotoran (fluometuron, N,N ­ dimethyl-Nr-(3-(trifluoromethyl)phenyl) urea) wash- off from native vegetation,

L. A. Gaston; D. J. Boquet; S. D. Dotch; M. A. Bosch

124

Are landscape complexity and farm specialisation related to land-use intensity of annual crop fields?  

Microsoft Academic Search

Little is known about the predictive value of landscape complexity and farm specialisation for land-use intensity, although this is critical for regional agri–environmental schemes and conservation of biodiversity. Here, we analysed land-use intensity of annual crop fields of 30 farms in northern Germany that were located in 15 landscapes differing in structural complexity ranging from 65% non-crop habitats. The proportion

Indra Roschewitz; Carsten Thies; Teja Tscharntke

2005-01-01

125

Stone bunds for soil conservation in the northern Ethiopian highlands: Impacts on soil fertility and crop yield  

Microsoft Academic Search

In the Ethiopian highlands, large-scale stone bund building programs are implemented to curb severe soil erosion. Development of soil fertility gradients is often mentioned as the major drawback of stone bund implementation, as it would result in a dramatic lowering of crop yield. Therefore, the objectives of this study are to assess soil fertility gradients on progressive terraces and their

Karen Vancampenhout; Jan Nyssen; Desta Gebremichael; Jozef Deckers; Jean Poesen; Mitiku Haile; Jan Moeyersons

2006-01-01

126

Short Rotation Woody Crops Program. Annual progress report for 1985  

Microsoft Academic Search

This report describes the technical progress and accomplishments in the Short Rotation Woody Crops Program (SRWCP) for the year ending September 30, 1985. The SRWCP is sponsored by the US Department of Energy's Biofuels and Municipal Waste Technology Division. The SRWCP is an integrated program of 17 resarch projects aimed at improving the productivity and economic efficiency of short-rotation intensive

J. W. Ranney; J. L. Trimble; L. L. Wright; P. A. Layton; R. D. Perlack; C. R. Wenzel; D. T. Curtin

1986-01-01

127

Examining Changes in Soil Organic Carbon with Oat and Rye Cover Crops Using Terrain Covariates  

Microsoft Academic Search

Winter cover crops have the potential to increase soil organic C in the corn (Zea mays L.)-soybean (Glycine max (L.) Merr.) rotation in the upper Midwest. Management effects on soil C, however, are often difficult to measure because of the spatial variation of soil C across the landscape. The objective of this study was to determine the effect of oat

T. C. Kaspar; T. B. Parkin; D. B. Jaynes; C. A. Cambardella; D. W. Meek; Y. S. Jung

2006-01-01

128

Evaporation from soils below sparse crops in contour hedgerow agroforestry in semi-arid Kenya  

Microsoft Academic Search

In many agricultural systems in the semi-arid tropics, crops use only a small fraction of the total rainfall. Agroforestry can greatly reduce some losses, especially on hill slopes, where soil evaporation, runoff and soil losses are important. This paper reports on soil evaporation from a rotation of intercropped maize and cowpea between contour hedgerows of pruned Senna siamea trees as

J. M. Kinama; C. J. Stigter; C. K. Ong; J. K. Ng’ang’a; F. N. Gichuki

2005-01-01

129

Influence of crop residues on trifluralin mineralization in a silty clay loam soil.  

PubMed

Trifluralin is typically applied onto crop residues (trash, stubble) at the soil surface, or onto the bare soil surface after the incorporation of crop residues into the soil. The objective of this study was to quantify the effect of the type and amount of crop residues in soil on trifluralin mineralization in a Wellwood silty clay loam soil. Leaves and stubble of Potato (Solanum tuberosum) (P); Canola (Brassica napus) (C), Wheat (Triticum aestivum) (W), Oats (Avena sativa), (O), and Alfalfa (Medicago sativa) (A) were added to soil microcosms at rates of 2%, 4%, 8% and 16% of the total soil weight (25 g). The type and amount of crop residues in soil had little influence on the trifluralin first-order mineralization rate constant, which ranged from 3.57E-03 day(-1) in soil with 16% A to 2.89E-02 day(-1) in soil with 8% W. The cumulative trifluralin mineralization at 113 days ranged from 1.15% in soil with 16% P to 3.21% in soil with 4% C, again demonstrating that the observed differences across the treatments are not of agronomic or environmental importance. PMID:17454379

Farenhorst, Annemieke

2007-01-01

130

Predicting greenhouse gas emissions and soil carbon from changing pasture to an energy crop.  

PubMed

Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L.) is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O) fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46-76 Mg dry mass · ha(-1)). Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq · m(-2) over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions. PMID:23991028

Duval, Benjamin D; Anderson-Teixeira, Kristina J; Davis, Sarah C; Keogh, Cindy; Long, Stephen P; Parton, William J; DeLucia, Evan H

2013-01-01

131

Measurement of the fluorescence of crop residues: A tool for controlling soil erosion  

NASA Technical Reports Server (NTRS)

Management of crop residues, the portion of a crop left in the field after harvest, is an important conservation practice for minimizing soil erosion and for improving water quality. Quantification of crop residue cover is required to evaluate the effectiveness of conservation tillage practices. Methods are needed to quantify residue cover that are rapid, accurate, and objective. The fluorescence of crop residue was found to be a broadband phenomenon with emission maxima at 420 to 495 nm for excitations of 350 to 420 nm. Soils had low intensity broadband emissions over the 400 to 690 nm region for excitations of 300 to 600 nm. The range of relative fluorescence intensities for the crop residues was much greater than the fluorescence observed of the soils. As the crop residues decompose their blue fluorescence values approach the fluorescence of the soil. Fluorescence techniques are concluded to be less ambiguous and better suited for discriminating crop residues and soils than reflectance methods. If properly implemented, fluorescence techniques can be used to quantify, not only crop residue cover, but also photosynthetic efficiency in the field.

Daughtry, C. S. T.; Mcmurtrey, J. E., III; Chappelle, E. W.; Hunter, W. J.

1994-01-01

132

SOIL AND CROP MANAGEMENT Grass and Legume Cover Crop Effects on Dry Matter and Nitrogen Accumulation  

Microsoft Academic Search

concentration of the cover crop mixture through biologi- cal N fixation and minimizing the potential for short- Careful cover crop management during the spring growth period term N immobilization (Ranells and Wagger, 1997). may allow farmers to maximize dry matter (DM) yield and N accumu- lation for the subsequent crop. A 2-yr study was conducted to deter- In cool northern

Jude J. O. Odhiambo; Arthur A. Bomke

133

Comparative soil and plant metabolism of carbosulfan, furathiocarb and carbofuran in Brussels sprouts, cauliflower and sugar beet crops  

Microsoft Academic Search

Brussels sprouts and cauliflower crops were soil treated at planting by one of the insecticides carbosulfan, furathiocarb, or carbofuran; moreover, a sugar beet crop was soil treated by carbofuran applied in the sowing furrow. In the soil, carbosulfan and furathiocarb were transformed into carbofuran, which then was transformed mainly into 3?ketocarbofuran, carbofuran phenol, and 3?ketocarbofuran phenol. In the soil of

Jean Rouchaud; Fabrice Gustin; Frans van de Steene; Christian Pelerents; Luc Vanparys; Michel de Proft; Edgard Seutin; Joel Gillet; Frans Benoit; Norbert Ceustermans

1990-01-01

134

Microbial community composition and carbon cycling within soil microenvironments of conventional, low-input, and organic cropping systems.  

PubMed

This study coupled stable isotope probing with phospholipid fatty acid analysis ((13)C-PLFA) to describe the role of microbial community composition in the short-term processing (i.e., C incorporation into microbial biomass and/or deposition or respiration of C) of root- versus residue-C and, ultimately, in long-term C sequestration in conventional (annual synthetic fertilizer applications), low-input (synthetic fertilizer and cover crop applied in alternating years), and organic (annual composted manure and cover crop additions) maize-tomato (Zea mays - Lycopersicum esculentum) cropping systems. During the maize growing season, we traced (13)C-labeled hairy vetch (Vicia dasycarpa) roots and residues into PLFAs extracted from soil microaggregates (53-250 ?m) and silt-and-clay (<53 ?m) particles. Total PLFA biomass was greatest in the organic (41.4 nmol g(-1) soil) and similar between the conventional and low-input systems (31.0 and 30.1 nmol g(-1) soil, respectively), with Gram-positive bacterial PLFA dominating the microbial communities in all systems. Although total PLFA-C derived from roots was over four times greater than from residues, relative distributions (mol%) of root- and residue-derived C into the microbial communities were not different among the three cropping systems. Additionally, neither the PLFA profiles nor the amount of root- and residue-C incorporation into the PLFAs of the microaggregates were consistently different when compared with the silt-and-clay particles. More fungal PLFA-C was measured, however, in microaggregates compared with silt-and-clay. The lack of differences between the mol% within the microbial communities of the cropping systems and between the PLFA-C in the microaggregates and the silt-and-clay may have been due to (i) insufficient differences in quality between roots and residues and/or (ii) the high N availability in these N-fertilized cropping systems that augmented the abilities of the microbial communities to process a wide range of substrate qualities. The main implications of this study are that (i) the greater short-term microbial processing of root- than residue-C can be a mechanistic explanation for the higher relative retention of root- over residue-C, but microbial community composition did not influence long-term C sequestration trends in the three cropping systems and (ii) in spite of the similarity between the microbial community profiles of the microaggregates and the silt-and-clay, more C was processed in the microaggregates by fungi, suggesting that the microaggregate is a relatively unique microenvironment for fungal activity. PMID:22267876

Kong, Angela Y Y; Scow, Kate M; Córdova-Kreylos, Ana Lucía; Holmes, William E; Six, Johan

2011-01-01

135

Microbial community composition and carbon cycling within soil microenvironments of conventional, low-input, and organic cropping systems  

PubMed Central

This study coupled stable isotope probing with phospholipid fatty acid analysis (13C-PLFA) to describe the role of microbial community composition in the short-term processing (i.e., C incorporation into microbial biomass and/or deposition or respiration of C) of root- versus residue-C and, ultimately, in long-term C sequestration in conventional (annual synthetic fertilizer applications), low-input (synthetic fertilizer and cover crop applied in alternating years), and organic (annual composted manure and cover crop additions) maize-tomato (Zea mays – Lycopersicum esculentum) cropping systems. During the maize growing season, we traced 13C-labeled hairy vetch (Vicia dasycarpa) roots and residues into PLFAs extracted from soil microaggregates (53–250 ?m) and silt-and-clay (<53 ?m) particles. Total PLFA biomass was greatest in the organic (41.4 nmol g-1 soil) and similar between the conventional and low-input systems (31.0 and 30.1 nmol g-1 soil, respectively), with Gram-positive bacterial PLFA dominating the microbial communities in all systems. Although total PLFA-C derived from roots was over four times greater than from residues, relative distributions (mol%) of root- and residue-derived C into the microbial communities were not different among the three cropping systems. Additionally, neither the PLFA profiles nor the amount of root- and residue-C incorporation into the PLFAs of the microaggregates were consistently different when compared with the silt-and-clay particles. More fungal PLFA-C was measured, however, in microaggregates compared with silt-and-clay. The lack of differences between the mol% within the microbial communities of the cropping systems and between the PLFA-C in the microaggregates and the silt-and-clay may have been due to (i) insufficient differences in quality between roots and residues and/or (ii) the high N availability in these N-fertilized cropping systems that augmented the abilities of the microbial communities to process a wide range of substrate qualities. The main implications of this study are that (i) the greater short-term microbial processing of root- than residue-C can be a mechanistic explanation for the higher relative retention of root- over residue-C, but microbial community composition did not influence long-term C sequestration trends in the three cropping systems and (ii) in spite of the similarity between the microbial community profiles of the microaggregates and the silt-and-clay, more C was processed in the microaggregates by fungi, suggesting that the microaggregate is a relatively unique microenvironment for fungal activity.

Kong, Angela Y.Y.; Scow, Kate M.; Cordova-Kreylos, Ana Lucia; Holmes, William E.; Six, Johan

2012-01-01

136

Perfluoroalkyl Acid Distribution in Various Plant Compartments of Edible Crops Grown in Biosolids-Amended soils.  

PubMed

Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var. dulce), tomato (Lycopersicon lycopersicum), and sugar snap pea (Pisum sativum var. macrocarpon) from an industrially impacted biosolids-amended soil, a municipal biosolids-amended soil, and a control soil. Individual concentrations of PFAAs, on a dry weight basis, in mature, edible portions of crops grown in soil amended with PFAA industrially impacted biosolids were highest for perfluorooctanoate (PFOA; 67 ng/g) in radish root, perfluorobutanoate (PFBA; 232 ng/g) in celery shoot, and PFBA (150 ng/g) in pea fruit. Comparatively, PFAA concentrations in edible compartments of crops grown in the municipal biosolids-amended soil and in the control soil were less than 25 ng/g. Bioaccumulation factors (BAFs) were calculated for the root, shoot, and fruit compartments (as applicable) of all crops grown in the industrially impacted soil. BAFs were highest for PFBA in the shoots of all crops, as well as in the fruit compartment of pea. Root-soil concentration factors (RCFs) for tomato and pea were independent of PFAA chain length, while radish and celery RCFs showed a slight decrease with increasing chain length. Shoot-soil concentration factors (SCFs) for all crops showed a decrease with increasing chain length (0.11 to 0.36 log decrease per CF2 group). The biggest decrease (0.54-0.58 log decrease per CF2 group) was seen in fruit-soil concentration factors (FCFs). Crop anatomy and PFAA properties were utilized to explain data trends. In general, fruit crops were found to accumulate fewer long-chain PFAAs than shoot or root crops presumably due to an increasing number of biological barriers as the contaminant is transported throughout the plant (roots to shoots to fruits). These data were incorporated into a preliminary conceptual framework for PFAA accumulation in edible crops. In addition, these data suggest that edible crops grown in soils conventionally amended for nutrients with biosolids (that are not impacted by PFAA industries) are unlikely a significant source of long-chain PFAA exposure to humans. PMID:24918303

Blaine, Andrea C; Rich, Courtney D; Sedlacko, Erin M; Hundal, Lakhwinder S; Kumar, Kuldip; Lau, Christopher; Mills, Marc A; Harris, Kimberly M; Higgins, Christopher P

2014-07-15

137

Impact of cover crops and tillage on porosity of podzolic soil  

NASA Astrophysics Data System (ADS)

The aim of the study was to determine the influence of cover crops biomass, mixed with the soil on different dates and with the use of different tools in field conditions. The cover crop biomass had a beneficial influence on the total porosity of the 0-20 cm layer of the soil after winter. The highest porosity was achievedwith cover crops of buckwheat, phacelia and mustard, the lowest with rye. During the vegetation period the highest porosity of soil was observed in the ridges. Among the remaining non-ploughing cultivations, pre-winter use of stubble cultivator proved to have a beneficial influence on the soil porosity, providing results comparable to those achieved in conventional tillage. The differential porosity of the soil was modified not only by the catch crops and the cultivation methods applied, but also by the sample collection dates, and it did change during the vegetation period. The highest content of macropores after winter was observed for the phacelia cover crop, and the lowest in the case of cultivation without any cover crops. Pre-winter tillage with the use of a stubble cultivator increased the amount of macropores in soil in spring, and caused the biggest participation of mesopores as compared with other non-ploughing cultivation treatments of the soil. The smallest amount of mesopores was found in the ridges.

B?a?ewicz-Wo?niak, M.; Konopiñski, M.

2013-09-01

138

Influence of tillage, residue management, and crop rotation on soil microbial biomass and catabolic diversity  

Microsoft Academic Search

The densely populated, intensively cropped subtropical highlands of the world have agricultural sustainability problems from soil erosion and fertility decline. In 1991, the International Maize and Wheat Improvement Center (CIMMYT) initiated a long-term field experiment at its semi-arid highland experiment station in Mexico (2240masl; 19.31°N, 98.50°W; Cumulic Phaeozem) to investigate the long-term effects of tillage\\/seeding practices, crop rotations, and crop

Bram Govaerts; Monica Mezzalama; Yusuke Unno; Ken D. Sayre; Marco Luna-Guido; Katrien Vanherck; Luc Dendooven; Jozef Deckers

2007-01-01

139

Crop Residue Management to Reduce Erosion and Improve Soil Quality: Northern Great Plains.  

National Technical Information Service (NTIS)

This publication summarizes research and experience that show the potential benefits and problems related to decreasing tillage and leaving more residues on the soil surface. Experts discuss the equipment, management practices, crop protection chemicals, ...

W. C. Moldenhauer A. L. Black

1994-01-01

140

Exploring soil bacterial communities in different peanut-cropping sequences using multiple molecular approaches.  

PubMed

Soil bacterial communities have significant influence on soilborne plant pathogens and, thus, crop health. The present study focuses on ribotyping soil bacterial communities in different peanut-cropping sequences in Alabama. The objective was to identify changes in microbial assemblages in response to cropping sequences that can play a role in managing soilborne plant pathogens in peanut. Four peanut-cropping sequences were sampled at the Wiregrass Research Station, Headland, AL in 2006 and 2007, including continuous peanut, 4 years of bahiagrass followed by peanut, peanut-cotton, and peanut-corn-cotton. Soil sampling was done at early and mid-season and at harvest. Bacterial community structure was assessed using ribosomal intergenic spacer analysis (RISA) combined with 16S rRNA cloning and sequencing. RISA results indicated >70% dissimilarities among different cropping sequences. However, 90% similarities were noticed among replicated plots of the same cropping sequences. Cropping sequences and time of soil sampling had considerable effect on soil microbial community structure. Bahiagrass rotation with peanut was found to have the highest bacterial diversity, as indicated by a high Shannon Weaver Diversity index. Overall, higher bacterial diversity was observed with bahiagrass and corn rotations compared with continuous peanut. The bacterial divisions Proteobacteria, Acidobacteria, Firmicutes, Bacteroidetes, and Actinomycetes were the predominant bacterial phyla found in all peanut-cropping sequences. The Proteobacteria taxa in these soils were negatively correlated with the abundance of members of division Firmicutes but, conversely, had a significant positive correlation with Gemmatimonadetes taxa. The prevalence of the division Actinomycetes was negatively correlated with the relative abundance of members of division Verrucomicrobia. These results indicate complex interactions among soil bacteria that are important contributors to crop health. PMID:21281114

Sudini, Hari; Liles, Mark R; Arias, Covadonga R; Bowen, Kira L; Huettel, Robin N

2011-07-01

141

Sensitivity of crop model predictions to entire meteorological and soil input datasets highlights vulnerability to drought  

Microsoft Academic Search

Crop growth models are increasingly used as part of research into areas such as climate change and bioenergy, so it is particularly important to understand the effects of environmental inputs on model results. Rather than investigating the effects of separate input parameters, we assess results obtained from a crop growth model using a selection of entire meteorological and soil input

Mark Pogson; Astley Hastings; Pete Smith

142

Phosphorus acquisition and cycling in crop and pasture systems in low fertility tropical soils  

Microsoft Academic Search

Soil-plant processes which enhance P acquisition and cycling in low-P Oxisols were investigated in a crop rotations and ley pasture systems experiment on the Colombian eastern plains. Comparison of rooting patterns indicated that, despite low available P at depth, there are important differences in root size and distribution among native savanna, introduced forage and crop species which affect their ability

D. K. Friesen; I. M. Rao; R. J. Thomas; A. Oberson; J. I. Sanz

1997-01-01

143

Climate change and the flowering time of annual crops.  

PubMed

Crop production is inherently sensitive to variability in climate. Temperature is a major determinant of the rate of plant development and, under climate change, warmer temperatures that shorten development stages of determinate crops will most probably reduce the yield of a given variety. Earlier crop flowering and maturity have been observed and documented in recent decades, and these are often associated with warmer (spring) temperatures. However, farm management practices have also changed and the attribution of observed changes in phenology to climate change per se is difficult. Increases in atmospheric [CO(2)] often advance the time of flowering by a few days, but measurements in FACE (free air CO(2) enrichment) field-based experiments suggest that elevated [CO(2)] has little or no effect on the rate of development other than small advances in development associated with a warmer canopy temperature. The rate of development (inverse of the duration from sowing to flowering) is largely determined by responses to temperature and photoperiod, and the effects of temperature and of photoperiod at optimum and suboptimum temperatures can be quantified and predicted. However, responses to temperature, and more particularly photoperiod, at supraoptimal temperature are not well understood. Analysis of a comprehensive data set of time to tassel initiation in maize (Zea mays) with a wide range of photoperiods above and below the optimum suggests that photoperiod modulates the negative effects of temperature above the optimum. A simulation analysis of the effects of prescribed increases in temperature (0-6 degrees C in +1 degree C steps) and temperature variability (0% and +50%) on days to tassel initiation showed that tassel initiation occurs later, and variability was increased, as the temperature exceeds the optimum in models both with and without photoperiod sensitivity. However, the inclusion of photoperiod sensitivity above the optimum temperature resulted in a higher apparent optimum temperature and less variability in the time of tassel initiation. Given the importance of changes in plant development for crop yield under climate change, the effects of photoperiod and temperature on development rates above the optimum temperature clearly merit further research, and some of the knowledge gaps are identified herein. PMID:19505929

Craufurd, P Q; Wheeler, T R

2009-01-01

144

[Difference of several major nutrients accumulation in vegetable and cereal crop soils].  

PubMed

Investigation and determination of several major nutrients in different types of vegetable and cereal crop soils were carried out in the Guanzhong Plain in Shaanxi Province. The results showed that organic matter, nitrogen, phosphorus and potassium accumulated more in the 0-200 cm profile of vegetable soils than in that of cereal crop soils. However, the accumulation degrees were different with different nutrient forms. The total amount of nitrate-N in the soil profile of plastic greenhouse and usual vegetable field was 1520.9 kg.hm-2 and 1358.8 kg.hm-2, being 5.2 and 4.5 times higher than that in the cereal crop fields respectively. The total amount of available-P was respectively 978.1 kg.hm-2 and 503.3 kg.hm-2 in the two vegetable soils, and 136.2 kg.hm-2 in cereal crop soils, and the former two were 6.2 and 2.7 times higher than the latter. For other nutrients, organic matter in cereal crop soil was 249.4 Mg.hm-2, and that in plastic greenhouse and usual vegetable soil was 280.5 Mg.hm-2 and 269.3 Mg.hm-2, respectively, which were only 12.5% and 8.0% higher than that in cereal crop soils. The total-N in plastic greenhouse and usual vegetable soils was 37.5 Mg.hm-2 and 32.7 Mg.hm-2, which was 36.2% and 18.6% higher than that (27.5 Mg.hm-2) in cereal crop soils, respectively. The ammonium-N was 211.5 kg.hm-2 and 197.8 kg.hm-2, which was 29.6% and 21.2% higher than that (163.2 kg.hm-2) in cereal crop soils. The available-K was 6567.8 kg.hm-2 and 5523.6 kg.hm-2, which was 30.6% and 9.8% higher than that (5029.7 kg.hm-2) in cereal crop soils. Furthermore, serious nutrient leaching occurred in vegetable soil profiles due to over-fertilization and irrigation. PMID:12561168

Wang, Zhaohui; Zong, Zhiqiang; Li, Shengxiu

2002-09-01

145

Micronutrient Constraints to Crop Production in Soils with Mediterranean-type Characteristics: A Review  

Microsoft Academic Search

Mediterranean-type soils generally have free CaCO3, high pH, and low organic matter. Consequently, nutrient disorders in these soils are the most important limiting factor to crop production, second only to moisture stress. Major problems are deficiencies of nitrogen and phosphorus; however, recent research has revealed that micronutrient problems are also hampering crop production. Unlike major nutrient deficiencies, micronutrient problems are

A. Rashid; J. Ryan

2004-01-01

146

Impact of untreated wastewater irrigation on soils and crops in Shiraz suburban area, SW Iran  

Microsoft Academic Search

In this study an assessment is made of the negative impacts of wastewater irrigation on soils and crops sampled along the\\u000a Khoshk River channel in suburban area of Shiraz City, SW Iran. For this purpose, samples of soil profiles (0–60 cm in depth)\\u000a and crops were collected from two wastewater irrigated sites and a tube well-irrigated (control) site. Total concentrations\\u000a of

Afshin Qishlaqi; Farid Moore; Giti Forghani

2008-01-01

147

Effects of fertilisation and edaphic properties on soil-associated Collembola in crop rotation  

Microsoft Academic Search

In this study, the Collembola population and their seasonal fluctuations were measured on light-textured field soils (Cambic Arenosol and Stagnic Luvisol) in Southern Estonia. A ten-year-old field experiment with potato and spring cereals in crop rotation under different fertilisation was the main sampling area. Additional research was carried out on sandy soils cropped with spring barley. There was also considerable

A. Kanal

2004-01-01

148

Selenium content of Belgian cultivated soils and its uptake by field crops and vegetables.  

PubMed

A series of 695 food crops were collected on 539 soils throughout Belgium. All samples were collected on commercial production fields, omitting private gardens. All crops were analyzed for their selenium (Se) concentration. The soils represent different soil types occurring in Belgium, with soil textures ranging from sand to silt loam, and including a few clay soils. They were analyzed for Se concentration, organic carbon content, cation exchange capacity and extractable sulphur (S) concentration. The Se concentrations in the soils were low (range 0.14-0.70 mg kg(-1) dw), but increasing soil Se concentrations were observed with increasing clay content. Stepwise multiple regressions were applied to determine relations between Se concentrations in crops and soil characteristics. Among field crops, wheat is the most important accumulator of selenium but the concentration remains rather low on the Belgian low Se-soils. Based on dry weight, leafy vegetables contain more Se than wheat. The soil is the most important source of Se and the element is transported with the water stream to the leaves, where it is accumulated. Vegetables rich in S, e.g. some Brassica and Allium species, have a higher capacity to accumulate Se as it can replace S in the proteins, although this accumulation is still limited at low soil Se concentrations. In loamy soils, weak correlations were found between the soil Se concentration and its concentration in wheat and potato. The uptake of Se increased with increasing pH. The Se concentrations in Belgian soils are far too low to generate a driving force on Se uptake. General climatic conditions such as temperature, air humidity and soil moisture are also important for the transfer of Se within the plant, and plant linked factors such as cultivar, growth stage and edible part are important as well, although their influence remains limited at low soil Se concentrations. PMID:24013513

De Temmerman, Ludwig; Waegeneers, Nadia; Thiry, Céline; Du Laing, Gijs; Tack, Filip; Ruttens, Ann

2014-01-15

149

Transfer of cadmium, lead, and zinc from industrially contaminated soil to crop plants: A field study  

Microsoft Academic Search

The documeneed adverse health effects of soil Cd and Pb have led to public concern over soil contamination with metals. A 4-year field experiment was conducted to study the transfer of Cd, Pb, and Zn from soil contaminated by smelter flue-dust to crop plants grown in a rotation. The soil was amended with Pb?Zn smelter flue-dust (2–66.8 kg per 10

S. Dudka; M. Piotrowska; H. Terelak

1996-01-01

150

Role of manures and crop residue in alleviating soil fertility constraints to crop production: With special reference to the Sahelian and Sudanian zones of West Africa  

Microsoft Academic Search

In the West African semi-arid tropics (WASAT), continuous cultivation leads to drastically reduced levels of soil organic matter. Such reductions in the level of soil organic matter have resulted in decreased soil productivity. The addition of organic materials either in the form of manures or crop residue has beneficial effects on the soils' chemical and physical properties. For many of

A. Bationo; A. U. Mokwunye

1991-01-01

151

Dissipation and mobility of flumetsulam in the soil of corn crops.  

PubMed

The triazolopyrimidine sulfonanilide herbicide flumetsulam has been applied pre- or post-emergence at the rate of 20 g a.i. ha-1 on corn crops grown on sandy-loam or loamy-sand soils. A procedure has been developed for the analysis of flumetsulam in soil using gas-chromatography and gas-chromatography combined with mass spectrometry, after methylation of flumetsulam and purification of the soil extracts by repeated thin-layer chromatographies. The dissipation of flumetsulam in the 0-8 cm surface soil layer followed a first order kinetics. The flumetsulam soil half-life was about 41 days for the crops grown on sandy-loam soil, and 30 days for the crop grown on loamy-sand soil. At the corn harvest in September, only 9 to 13% of the applied dose of flumetsulam remained in soil, what is a common value for the herbicides at the crop harvest. The heavy rains and the soft temperatures of the autumn should dissipate these low residues within the one or two months period after the harvest. When applied at the rate of 20 g a.i. ha-1, the persistence of flumetsulam in field soil thus was moderate. During the crops and until the harvest, in the 8-15 cm surface soil layer, low concentrations of flumetsulam at the limit of the analytical sensitivity (0.3 microgram flumetsulam kg-1 dry soil) were observed temporarily; in the 15-20 cm surface soil layer, flumetsulam was never detected, showing that flumetsulam was strongly adsorbed onto the soil and its organic matter. PMID:12696407

Rouchaud, J; Neus, O; Eelen, H; Bulcke, R

2002-01-01

152

Spatial variation of corn canopy temperature as dependent upon soil texture and crop rooting characteristics  

NASA Technical Reports Server (NTRS)

A soil plant atmosphere model for corn (Zea mays L.) together with the scaling theory for soil hydraulic heterogeneity are used to study the sensitivity of spatial variation of canopy temperature to field averaged soil texture and crop rooting characteristics. The soil plant atmosphere model explicitly solves a continuity equation for water flux resulting from root water uptake, changes in plant water storage and transpirational flux. Dynamical equations for root zone soil water potential and the plant water storage models the progressive drying of soil, and day time dehydration and night time hydration of the crop. The statistic of scaling parameter which describes the spatial variation of soil hydraulic conductivity and matric potential is assumed to be independent of soil texture class. The field averaged soil hydraulic characteristics are chosen to be representative of loamy sand and clay loam soils. Two rooting characteristics are chosen, one shallow and the other deep rooted. The simulation shows that the range of canopy temperatures in the clayey soil is less than 1K, but for the sandy soil the range is about 2.5 and 5.0 K, respectively, for the shallow and deep rooted crops.

Choudhury, B. J.

1983-01-01

153

Alternative soil quality indices for evaluating the effect of intensive cropping, fertilisation and manuring for 31 years in the semi-arid soils of India  

Microsoft Academic Search

Soil quality assessment provides a tool for evaluating the sustainability of alternative soil management practices. Our objective\\u000a was to develop the most sensitive soil quality index for evaluating fertilizer, farm yard manure (FYM), and crop management\\u000a practices on a semiarid Inceptisol in India. Soil indicators and crop yield data from a long-term (31 years) fertilizer, manure,\\u000a and crop rotation (maize, wheat,

Reginald Ebhin Masto; Pramod K. Chhonkar; Dhyan Singh; Ashok K. Patra

2008-01-01

154

Estimating soil moisture and the relationship with crop yield using surface temperature and vegetation index  

NASA Astrophysics Data System (ADS)

Soil moisture availability affects rainfed crop yield. Therefore, the development of methods for pre-harvest yield prediction is essential for the food security. A study was carried out to estimate regional crop yield using the Temperature Vegetation Dryness Index (TVDI). Triangular scatters from land surface temperature (LST) and enhanced vegetation index (EVI) space from MODIS (Moderate Resolution Imaging Spectroradiometer) were utilized to obtain TVDI and to estimate soil moisture availability. Then soybean and wheat crops yield was estimated on four agro-climatic zones of Argentine Pampas. TVDI showed a strong correlation with soil moisture measurements, with R2 values ranged from 0.61 to 0.83 and also it was in agreement with spatial pattern of soil moisture. Moreover, results showed that TVDI data can be used effectively to predict crop yield on the Argentine Pampas. Depending on the agro-climatic zone, R2 values ranged from 0.68 to 0.79 for soybean crop and 0.76 to 0.81 for wheat. The RMSE values were 366 and 380 kg ha-1 for soybean and they varied between 300 and 550 kg ha-1 in the case of wheat crop. When expressed as percentages of actual yield, the RMSE values ranged from 12% to 13% for soybean and 14% to 22% for wheat. The bias values indicated that the obtained models underestimated soybean and wheat yield. Accurate crop grain yield forecast using the developed regression models was achieved one to three months before harvest. In many cases the results were better than others obtained using only a vegetation index, showing the aptitude of surface temperature and vegetation index combination to reflect the crop water condition. Finally, the analysis of a wide range of soil moisture availability allowed us to develop a generalized model of crop yield and dryness index relationship which could be applicable in other regions and crops at regional scale.

Holzman, M. E.; Rivas, R.; Piccolo, M. C.

2014-05-01

155

Effects of mulching and catch cropping on soil temperature, soil moisture and wheat yield on the Loess Plateau of China  

Microsoft Academic Search

Soil management can notably influence crop production under dryland farming in semiarid areas. Field experiments were conducted, from October 2001 to September 2004, with an attempt to evaluate the effects of field management regimes on thermal status at an upland site; and soil water and wheat production in a winter wheat (Triticum aestivum L.) system at upland, terrace land and

Shulan Zhang; Lars Lövdahl; Harald Grip; Yanan Tong; Xueyun Yang; Quanjiu Wang

2009-01-01

156

[Fungal population structure and its biological effect in rhizosphere soil of continuously cropped potato].  

PubMed

Continuous cropping obstacle is one of the main restriction factors in potato industry. In order to explore the mechanisms of potato's continuous cropping obstacle and to reduce the impact on potato's tuber yield, a field experiment combined with PCR-DGGE molecular fingerprinting was conducted to investigate the fungal population structure and its biological effect in rhizosphere soil of continuously cropped potato. With the increasing year of potato' s continuous cropping, the numbers of visible bands in rhizosphere fungal DGGE profiles increased obviously. As compared with that of CK (rotation cropping), the operational taxonomic unit (OTU) in treatments of one to five years continuous cropping was increased by 38.5%, 38.5%, 30.8%, 46.2%, and 76.9% respectively, indicating that potato's continuous cropping caused an obvious increase in the individual numbers of dominant fungal populations in rhizosphere soil. Also with the increasing year of potato's continuous cropping, the similarity of the fungal population structure among the treatments had a gradual decrease. The sequencing of the fungal DGGE bands showed that with the increasing year of continuous cropping, the numbers of the potato's rhizosphere soil-borne pathogens Fusarium oxysporum and F. solani increased obviously, while the number of Chaetomium globosum, as a biocontrol species, had a marked decrease in the fifth year of continuous cropping. It was suggested that potato' s continuous cropping caused the pathogen fungal populations become the dominant microbial populations in rhizosphere soil, and the rhizosphere micro-ecological environment deteriorated, which in turn affected the root system, making the root vigor and its absorption area reduced, and ultimately, the tuber yield decreased markedly. PMID:23431794

Meng, Pin-Pin; Liu, Xing; Qiu, Hui-Zhen; Zhang, Wen-Ming; Zhang, Chun-Hong; Wang, Di; Zhang, Jun-Lian; Shen, Qi-Rong

2012-11-01

157

Global sensitivity analysis measures the quality of parameter estimation: The case of soil parameters and a crop model  

Microsoft Academic Search

One common limitation of the use of crop models for decision making in precise crop management is the need for accurate values of soil parameters for a whole field. Estimating these parameters from data observed on the crop, using a crop model, is an interesting possibility. Nevertheless, the quality of the estimation depends on the sensitivity of model output variables

Hubert Varella; Martine Guérif; Samuel Buis

2010-01-01

158

Detecting crop yield reduction due to irrigation-induced soil salinization in South-West Russia  

NASA Astrophysics Data System (ADS)

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.

Argaman, E.; Beets, W.; Croes, J.; Keesstra, S.; Verzandvoort, S.; Zeiliguer, A.

2012-04-01

159

Phytotoxicity of Ryegrass and Clover Cover Crops, and a Lucerne Alley Crop for No-till Vegetable Production  

Microsoft Academic Search

Experiments were conducted under controlled conditions to test whether the residues of cover crops or alley crops were phytotoxic to vegetable seedlings in a no-tillage cropping system. Soil and residue samples were collected from a field experiment where subterranean clover Trifolium subterrcmeum L. var. brachycalycinum and annual ryegrass Lolium rigidum Gand. were grown as cover crops, and lucerne Medicago sativa

R. J. Stirzaker; D. G. Bunn

1996-01-01

160

Effect of crop residue incorporation on soil organic carbon (SOC) and greenhouse gas (GHG) emissions in European agricultural soils  

NASA Astrophysics Data System (ADS)

Soil organic matter (SOM) improves soil physical (e.g. increased aggregate stability), chemical (e.g. cation exchange capacity) and biological (e.g. biodiversity, earthworms) properties. The sequestration of soil organic carbon (SOC) may mitigate climate change. However, as much as 25-75% of the initial SOC in world agricultural soils may have been lost due to intensive agriculture (Lal, 2013). The European Commission has described the decline of organic matter (OM) as one of the major threats to soils (COM(2006) 231). Incorporation of crop residues may be a sustainable and cost-efficient management practice to maintain the SOC levels and to increase soil fertility in European agricultural soils. Especially Mediterranean soils that have low initial SOC concentrations, and areas where stockless croplands predominate may be suitable for crop residue incorporation. In this study, we aim to quantify the effects of crop residue incorporation on SOC and GHG emissions (CO2 and N2O) in different environmental zones (ENZs, Metzger et al., 2005) in Europe. Response ratios for SOC and GHG emissions were calculated from pairwise comparisons between crop residue incorporation and removal. Specifically, we investigated whether ENZs, clay content and experiment duration influence the response ratios. In addition, we studied how response ratios of SOM and crop yields were correlated. A total of 718 response ratios (RR) were derived from a total of 39 publications, representing 50 experiments (46 field and 4 laboratory) and 15 countries. The SOC concentrations and stocks increased by approximately 10% following crop residue incorporation. In contrast, CO2 emissions were approximately six times and N2O emissions 12 times higher following crop residue incorporation. The effect of ENZ on the response ratios was not significant. For SOC concentration, the >35% clay content had significantly approximately 8% higher response ratios compared to 18-35% clay content. As the duration of the experiment rose, RR for SOC concentration and stock increased. For N2O emissions, RR was significantly higher in <5 years experiment duration compared to 11-15 years experiment duration. For GHG emissions, the RRs were significantly higher when vegetable crop residues were incorporated instead of cereal crop residues. No significant correlations were found between RR for SOC concentration and yields, but differences between sites could be detected. We conclude that crop residue incorporation is an important management practice for maintaining SOC concentrations and stocks. Its influence in increasing GHG emissions should not be overlooked as the data availability from field experiments on GHG emissions is still scarce.

Lehtinen, Taru; Schlatter, Norman; Baumgarten, Andreas; Bechini, Luca; Krüger, Janine; Grignani, Carlo; Zavattaro, Laura; Costamagna, Chiara; Spiegel, Heide

2014-05-01

161

Dynamic Succession of Soil Bacterial Community during Continuous Cropping of Peanut (Arachis hypogaea L.)  

PubMed Central

Plant health and soil fertility are affected by plant–microbial interactions in soils. Peanut is an important oil crop worldwide and shows considerable adaptability, but growth and yield are negatively affected by continuous cropping. In this study, 16S rRNA gene clone library analyses were used to study the succession of soil bacterial communities under continuous peanut cultivation. Six libraries were constructed for peanut over three continuous cropping cycles and during its seedling and pod-maturing growth stages. Cluster analyses indicated that soil bacterial assemblages obtained from the same peanut cropping cycle were similar, regardless of growth period. The diversity of bacterial sequences identified in each growth stage library of the three peanut cropping cycles was high and these sequences were affiliated with 21 bacterial groups. Eight phyla: Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Gemmatimonadetes, Planctomycetes, Proteobacteria and Verrucomicrobia were dominant. The related bacterial phylotypes dynamic changed during continuous cropping progress of peanut. This study demonstrated that the bacterial populations especially the beneficial populations were positively selected. The simplification of the beneficial microbial communities such as the phylotypes of Alteromonadales, Burkholderiales, Flavobacteriales, Pseudomonadales, Rhizobiales and Rhodospirillales could be important factors contributing to the decline in peanut yield under continuous cropping. The microbial phylotypes that did not successively changed with continuous cropping, such as populations related to Rhizobiales and Rhodospirillales, could potentially resist stress due to continuous cropping and deserve attention. In addition, some phylotypes, such as Acidobacteriales, Chromatiales and Gemmatimonadales, showed a contrary tendency, their abundance or diversity increased with continuous peanut cropping progress. Some bacterial phylotypes including Acidobacteriales, Burkholderiales, Bdellovibrionales, and so on, also were affected by plant age.

Chen, Mingna; Li, Xiao; Yang, Qingli; Chi, Xiaoyuan; Pan, Lijuan; Chen, Na; Yang, Zhen; Wang, Tong; Wang, Mian; Yu, Shanlin

2014-01-01

162

Intraseasonal dynamics of soil moisture variability within a small agricultural maize cropped field  

Microsoft Academic Search

The spatio-temporal dynamics of soil water content was investigated within a small agricultural maize cropped field located in Belgium. Soil moisture measurements were intensively made between May 30 and September 13, 1999 on 28 sampling locations at different depths (from 0 to 125cm) with both TDR and neutron probe. The adopted sampling scheme resulted in a comprehensive data set of

F. Hupet; M Vanclooster

2002-01-01

163

Nutrient transformation in soil due to addition of organic manure and growing crops  

Microsoft Academic Search

Maintaining organic pools of nitrogen (N) in soil is important for providing a steady flux of N in soil solution. Bioslurry, which is the product obtained from anaerobically digested (methanised) farm yard manure (FYM), is an efficient source of organic manure with capability to supply nutrients, particularly N to crops. A study was conducted to see the equilibrium relationship between

K. L. Sharma; J. C. Bajaj; S. K. Das; U. M. B. Rao; K. Ramalingaswami

1992-01-01

164

Modeling regional crop yield and irrigation demand using SMAP type of soil moisture data  

NASA Astrophysics Data System (ADS)

Agricultural models, such as Decision Support System for Agrotechnology Transfer - Cropping Systems Model (DSSAT-CSM) (Tsuji, et al., 1994), have been developed to predict the yield of various crops at field and regional scales. The model simulations of crop yields provide essential information for water resources management. One key input of the agricultural models is soil moisture. So far there are no observed soil moisture data covering the entire US with adequate time (daily) and space (1 km or less) resolutions preferred for model simulation of crop yields. Spatially and temporally downscaled data from the upcoming Soil Moisture Active Passive (SMAP) mission can fill this data gap through the generation of fine resolution soil moisture maps that can be incorporated into DSSAT-CSM model. This study will explore the impact downscaled remotely-sensed soil moisture data can have on agricultural model forecasts of agricultural yield and irrigation demand using synthetically generated data sets exhibiting statistical characteristics (uncertainty) similar to the upcoming SMAP products. It is expected that incorporating this data into agricultural model will prove especially useful for cases in which soil water conductivity characteristics and/or precipitation amount at a specific site of interest are not fully known; furthermore, a proposed Bayesian analysis is expected to generate a soil moisture sequence that reduces the uncertainty in modeled yield and irrigation demand compared to using downscaled remotely-sensed soil moisture or precipitation data alone. References Tsuji, G., Uehara, G., and Balas, S. (1994). DSSAT V3, University of Hawaii, Honolulu.

El Sharif, H. A.; Wang, J.; Georgakakos, A. P.; Bras, R. L.

2013-12-01

165

Geophysical Tools and Digital Elevation Models: Tools for Understanding Crop Yield and Soil Variability  

Microsoft Academic Search

Since the adoption of precision agriculture land managers require tools to map soils at a finer scale to understand variability in yield maps. The increasing input costs to horticultural crops are also instigating the need for finer detailed soil information to enable land managers to profit from variable rate technology. This paper discusses electromagnetic induction (EMI), gamma ray spectrometry (GRS)

Paul Rampant; M Abuzar

166

TOMATO YIELD AND SOIL QUALITY AS INFLUENCED BY TILLAGE, COVER CROPPING, AND NITROGEN FERTILIZATION  

Microsoft Academic Search

Tomato yield and soil quality may be influenced by management practices and climatic conditions. We examined the effects of tillage (no-till, chisel plowing, and moldboard plowing), cover crop (hairy vetch (Vicia villosa Roth) and no hairy vetch), and N fertilization (0, 80, and 160 lb N acre-1) on tomato yield and N uptake, root growth, and soil C and N

Upendra M. Sainju; Bharat P. Singh; Sidat Yaffa

167

Spatial variation of soil enzyme activities and microbial functional diversity in temperate alley cropping systems  

Microsoft Academic Search

Spatially dependent patterns in microbial properties may exist in temperate alley cropping systems due to differences in litter quality and microclimate in areas under trees compared to those in the alleys. The effect of tree row location was evaluated for its impact on soil enzyme activities and Biolog substrate use patterns. Soils were sampled to a depth of 30 cm at

Nancy W. Mungai; Peter P. Motavalli; Robert J. Kremer; Kelly A. Nelson

2005-01-01

168

Effects of tillage and winter cover cropping on microbial substrate-induced respiration and soil aggregation in two Japanese fields  

Microsoft Academic Search

We hypothesized that cover cropping could increase soil microbial activities under various tillage systems and that increased microbial activities would improve soil properties. Soil sampling was conducted at two fields in Japan in 2009. At the Ibaraki field (Andosol, clay loam), three tillage practices (no-tillage, plowing to 30?cm, and rotary tillage to 15?cm) and three types of winter cover cropping

Tomomi Nakamoto; Masakazu Komatsuzaki; Toshiyuki Hirata; Hajime Araki

2012-01-01

169

Mitigating the effects of soil and residue water contents on remotely sensed estimates of crop residue cover  

Microsoft Academic Search

Crop residues on the soil surface decrease soil erosion and increase soil organic carbon and the management of crop residues is an integral part of many conservation tillage systems. Current methods of measuring residue cover are inadequate for characterizing the spatial variability of residue cover over large fields. The objectives of this research were to determine the effects of water

C. S. T. Daughtry; E HUNTJR

2008-01-01

170

Farmers' Perception of Integrated Soil Fertility and Nutrient Management for Sustainable Crop Production: A Study of Rural Areas in Bangladesh  

ERIC Educational Resources Information Center

This study aimed to determine farmers' perception of integrated soil fertility and nutrient management for sustainable crop production. Integrated soil fertility (ISF) and nutrient management (NM) is an advanced approach to maintain soil fertility and to enhance crop productivity. A total number of 120 farmers from eight villages in four districts…

Farouque, Md. Golam; Takeya, Hiroyuki

2007-01-01

171

Effect of tillage systems and P-fertilization on soil physical and chemical properties, crop yield and nutrient uptake  

Microsoft Academic Search

Data from a long-term fertilization trial at the Institute for Crop and Soil Science in Braunschweig, Germany were used to evaluate the influence of tillage systems and phosphorus (P) fertilization on the physical and chemical properties of soil, P accumulation in soils, yield of various crops, and P uptake. The trial was set up in 1985. In 1998 two tillage

Iris Vogeler; Jutta Rogasik; Ute Funder; Kerstin Panten; Ewald Schnug

2009-01-01

172

Effect of soil acidity factors on yields and foliar composition of tropical root crops  

SciTech Connect

Tropical root crops, a major source of food for subsistence farmers, varied in their sensitivity to soil acidity factors. Tolerance to soil acidity is an important characteristic of crops for the humid tropics where soils are often very acid and lime-scarce and expensive. Experiments on two Ultisols and an Oxisol showed that three tropical root crops differed markedly in sensitivity to soil acicity factors. Yams (Dioscorea alata L.) were very sensitive to soil acidity with yields on a Ultisol decreasing from 70% of maximum when Al saturation of the effective cation exchange capacity of the soil was 10 to 25% of maximum when Al saturation was 40%. On the other hand, cassava (Manihot esculenta Crantz) was very tolerant to high levels of soil acidity, yielding about 85% of maximum with 60% Al saturation. Taniers (Xanthosoma sp.) were intermediate between yams and cassava in their tolerance to soil acidity yielding about 60% of maximum with 50% Al saturation of the soil. Foliar composition of cassava was not affected by soil acidity levels and that of yams and taniers was also unaffected except for Ca content which decreased with decreasing soil pH and increasing Al saturation.Response of these tropical root crops to soil acidity components was far more striking on Ultisols than on the Oxisol. For yams, soils should be limed to about pH 5.5 with essentially no exhangeable Al/sup 3 +/ present whereas high yields of taniers can be obtained at about pH 4.8 with 20% exchangeable Al/sup 3 +/ and of cassava at pH as low as 4.5 with 60% exchangeable Al/sup 3 +/.

Abruna-Rodriguez, F.; Vicente-Chandler, J.I. Rivera, E.; Rodriguez, J.

1982-09-01

173

Uptake of soil cadmium by three field crops and its prediction by a pH-dependent Freundlich sorption model  

Microsoft Academic Search

Crop contamination with cadmium is a function of soil contamination. Here we study the applicability of the soil solution\\u000a bioavailability hypothesis to Cd: that is, whether uptake of Cd was more directly related to its concentration or activity\\u000a in the soil solution than in the soil solid phase. Experimental data from past soil-crop surveys for Cd were used to test

P. Del Castilho; W. J. Chardon

1995-01-01

174

Long-term changes in organic matter of woodland soils cleared for arable cropping in Zimbabwe  

Microsoft Academic Search

Subsistence farmers in Africa depend largely on the soil organic matter to sustain crop productivity. Long-term changes in soil organic carbon and nitrogen were measured after woodland clearance for smallholder subsistence farming or for commercial farming. The contents of organic carbon and nitrogen in soil under reference woodlands were largest (53.3 t C ha-1, 4.88 t N ha-1) in a

S. Zingore; C. Manyame; P. Nyamugafata; K. E. Giller

2005-01-01

175

Soil microbial diversity and community structure under wheat as influenced by tillage and crop rotation  

Microsoft Academic Search

Soil microbial diversity is important to sustainable agriculture because microbes mediate many processes that support agricultural production. The BIOLOG™ system for detection of specific patterns of substrate utilization by bacteria was used to investigate the effects of tillage and crop rotation on the diversity and community structure of soil bacteria. In each of 2yr, soil was sampled (0–7.5cm) in the

N. Z. Lupwayi; W. A. Rice; G. W. Clayton

1998-01-01

176

Activity of protease extracted from rice-rhizosphere soils under double cropping of rice and wheat  

Microsoft Academic Search

Protease-active extracts were prepared from 2 rice-rhizosphere and non-rhizosphere soil samples 3 proteolytic isolates from the soil samples which were taken from water logged paddy fields (Gray Lowland Soils) under double cropping of rice and wheat that had been treated with chemical fertilizer (CF) or organic manure (OM). The activities were assayed and characterized using an artificial substrate, benzyloxycarbonyl-L-phenylalanyl-L-tyrosyl-L-leucine (ZFTL).

Koichi Hayano; Katsuji Watanabe; Susumu Asakawa

1995-01-01

177

Effect of Cropping System and Contouring or Download Sowing on Soil Water Erosion under no Tillage  

NASA Astrophysics Data System (ADS)

Water erosion is the main responsible factor of soil and water losses, thus also causing soil degradation, especially on agricultural land, and it is also one factor of degradation outside the place of the origin of erosion. No tillage agriculture has been practiced in the last few decades for the purposes of water erosion control in various regions of Brazil. However, it has been shown that no tillage does not adequately control water erosion unless other complementary conservationist practices such as contour tillage or terracement. Although the erosion problem is widely recognized, there are still difficulties in estimating their magnitude, the environmental impact and the economic consequences, especially when it occurs in a conservation system like no tillage. The aim of this study was to quantify runoff and soil losses by water erosion under five different soil tillage treatments at Santa Catarina State, Southern Brazil. A field study was carried out using a rotating-boom rainfall simulator with 64 mmh-1 rainfall intensity for 90 minutes. Four rainfall tests were applied over the experimental period, one in each of the successive soybean and maize crop stages. Both soil cover by surface crop residue and soil cover by soybean and maize plant canopy were measured immediately before each rainfall test. Soil and water losses were smaller when sowing in contour than when sowing downslope. Contouring has promoted an average reduction of 42% in soil losses and 20% in water losses. Maize crop has promoted an average reduction of 19% in soil losses and 12% in water losses, in relation to the soybean crop. Therefore runoff rates and soil losses were higher in the downslope plots and in the soybean crop. Soil cover by previous crop residue was an important factor for reducing soil losses. Runoff rates were influenced by the soil water content before each rainfall test (R2= 0.78). The highest runoff occurred during the third simulated rainfall test, with the 83% of the total rain applied; immediately before the test the soil moisture was 36%. The smallest losses occurred in the fourth test, with 55% of the total rain applied where the soil moisture immediately before the rainfall test was 25%.

Marioti, J.; Padilha, J.; Bertol, I.; Barbosa, F. T.; Ramos, J. C.; Werner, R. S.; Vidal Vázquez, E.; Tanaka, M. S.

2012-04-01

178

The Importance of Soil Protein Fate to PIP Crop Registration  

EPA Science Inventory

Plant Incorporated Protectant (PIP) crops are registered under the authority of the Federal Insecticide Fungicide and Rodenticide Act (FIFRA) and as part of this registration certain environmental fate information is required to properly judge the environmental compatibility of n...

179

Crop residues as soil amendments and feedstock for bioethanol production  

Microsoft Academic Search

Traditional solid fuels account for more than 90% of the energy supply for 3 billion people in developing countries. However, liquid biofuels (e.g., ethanol) are perceived as an important alternative to fossil fuel. Global crop residue production is estimated at about 4billionMg for all crops and 3billionMg per annum for lignocellulosic residues of cereals. One Mg of corn stover can

R. Lal

2008-01-01

180

Calibration approaches of cosmic-ray neutron sensing for soil moisture measurement in cropped fields  

NASA Astrophysics Data System (ADS)

Measurement of soil moisture at the plot or hill-slope scale is an important link between local vadose-zone hydrology and catchment hydrology. This study evaluates the applicability of the cosmic-ray neutron sensing for soil moisture in cropped fields. Measurements of cosmic-ray neutrons (fast neutrons) were performed at a lowland farmland in Bornim (Brandenburg, Germany) cropped with sunflower and winter rye. Three field calibration approaches and four different ways of integration the soil moisture profile to an integral value for cosmic-ray neutron sensing were evaluated in this study. The cosmic-ray sensing (CRS) probe was calibrated against a network of classical point-scale soil moisture measurements. A large CRS parameter variability was observed by choosing calibration periods within the different growing stages of sunflower and winter rye. Therefore, it was not possible to identify a single set of parameters perfectly estimating soil moisture for both sunflower and winter rye periods. On the other hand, CRS signal and its parameter variability could be understood by some crop characteristics and by predicting the attenuated neutrons by crop presence. This study proves the potentiality of the cosmic-ray neutron sensing at the field scale; however, its calibration needs to be adapted for seasonal vegetation in cropped fields.

Rivera Villarreyes, C. A.; Baroni, G.; Oswald, S. E.

2013-04-01

181

Aggregating available soil water holding capacity data for crop yield models  

NASA Technical Reports Server (NTRS)

The total amount of water available to plants that is held against gravity in a soil is usually estimated as the amount present at -0.03 MPa average water potential minus the amount present at -1.5 MPa water potential. This value, designated available water-holding capacity (AWHC), is a very important soil characteristic that is strongly and positively correlated to the inherent productivity of soils. In various applications, including assessing soil moisture status over large areas, it is necessary to group soil types or series as to their productivity. Current methods to classify AWHC of soils consider only total capacity of soil profiles and thus may group together soils which differ greatly in AWHC as a function of depth in the profile. A general approach for evaluating quantitatively the multidimensional nature of AWHC in soils is described. Data for 902 soil profiles, representing 184 soil series, in Indiana were obtained from the Soil Characterization Laboratory at Purdue University. The AWHC for each of ten 150-mm layers in each soil was established, based on soil texture and parent material. A multivariate clustering procedure was used to classify each soil profile into one of 4, 8, or 12 classes based upon ten-dimensional AWHC values. The optimum number of classes depends on the range of AWHC in the population of oil profiles analyzed and on the sensitivity of a crop to differences in distribution of water within the soil profile.

Seubert, C. E.; Daughtry, C. S. T.; Holt, D. A.; Baumgardner, M. F.

1984-01-01

182

Soil moisture mapping in an alley cropping system in Quebec, Canada  

NASA Astrophysics Data System (ADS)

Alley cropping is an agroforestry practice whereby trees are planted in rows, thus creating alleyways within which companion crops are grown. The alley cropping systems as we call them may not only influence the local thermal energy balance by changes in airflow and solar irradiance, but also affect water uptake in plant roots and evapotranspiration. However, our understanding of the soil water balance and regulating mechanisms in alley cropping systems is very limited compared to what we know about the more common monoculture farming. Root systems of the trees are known to interact with soil water dynamics, in that they tend to grow in the direction of soil layers with a water content corresponding to a pF between 2-2.4, and conversely, water flows in the direction of decreasing hydraulic head, which, close to the root system, is in the direction of the roots when the trees absorb water by applying a suction gradient. As such, the trees in alley cropping systems either improve the resilience to drought by retaining more water in the upper soil layers, or they compete with the crops for water. With the eye on the future environmental conditions that may result from a shift in the local climate in southern Quebec, Canada, our objective is to characterize and evaluate the influence of alley cropping systems on soil water dynamics under various climate conditions. In order to evaluate the interaction between root system and soil water dynamics, we adopt an approach divided into three steps: (i) a field campaign where we monitor soil water patterns on an alley cropping site during the growing season; (ii) simulation of these soil water patterns with the HYDRUS model for two-dimensional movement of water; and (iii) the evolution of these patterns for a given scenario of climate change. Our submission focuses on the field campaign in which we used forty-five frequency domain reflectometers (FDR) along a 25-m transect perpendicular to the tree rows in order to monitor moisture patterns within the first 100 cm of the soil. Analysis showed that the presence of trees has a pronounced influence on the water distribution within the soil. (This submission is part of Climate Change Action Plan 26 funded by Ouranos-ICAR.)

Hallema, D. W.; Rousseau, A. N.; Gumiere, S. J.

2012-12-01

183

NUTRIENT STOCKS ,N UTRIENT CYCLING, AND SOIL CHANGES IN COCOA ECOSYSTEMS :AR EVIEW  

Microsoft Academic Search

It is generally assumed that agricultural systems with perennial crops are more sustainable than systems with annual crops. Soil erosion is negligible and perennial crops have more closed nutrient cycling. Moreover, inorganic fertilizers are used more commonly in cash crops such as perennial crops so that soil fertility decline and nutrient mining are less likely to occur. In the past

Alfred E. Hartemink

184

Contribution of Multi-Frequency, MultiSensor, and Multi-Temporal Radar Data to Operational Annual Crop Mapping  

Microsoft Academic Search

Agriculture is an important economic sector in Canada. As a federal government department, Agriculture and Agri- Food Canada (AAFC) is responsible for delivering agricultural programs that promote economic and environmental sustainability. In order to make well-informed and targeted agricultural policies, information on agricultural land use (crop inventory) is needed on an annual basis. The information on crop inventory should be

Jiali Shang; Heather McNairn; Catherine Champagne; Xianfeng Jiao

2008-01-01

185

Strip-tilled cover cropping for managing nematodes, soil mesoarthropods, and weeds in a bitter melon agroecosystem.  

PubMed

A field trial was conducted to examine whether strip-tilled cover cropping followed by living mulch practice could suppress root-knot nematode (Meloidogyne incognita) and enhance beneficial nematodes and other soil mesofauna, while suppressing weeds throughout two vegetable cropping seasons. Sunn hemp (SH), Crotalaria juncea, and French marigold (MG), Tagetes patula, were grown for three months, strip-tilled, and bitter melon (Momordica charantia) seedlings were transplanted into the tilled strips; the experiment was conducted twice (Season I and II). Strip-tilled cover cropping with SH prolonged M. incognita suppression in Season I but not in Season II where suppression was counteracted with enhanced crop growth. Sunn hemp also consistently enhanced bacterivorous and fungivorous nematode population densities prior to cash crop planting, prolonged enhancement of the Enrichment Index towards the end of both cash crop cycles, and increased numbers of soil mesoarthropods. Strip-tilled cover cropping of SH followed by clipping of the living mulch as surface mulch also reduced broadleaf weed populations up to 3 to 4 weeks after cash crop planting. However, SH failed to reduce soil disturbance as indicated by the Structure Index. Marigold suppressed M. incognita efficiently when planted immediately following a M. incognita-susceptible crop, but did not enhance beneficial soil mesofauna including free-living nematodes and soil mesoarthropods. Strip-tilled cover cropping of MG reduced broadleaf weed populations prior to cash crop planting in Season II, but this weed suppression did not last beyond the initial cash crop cycle. PMID:22736847

Marahatta, Sharadchandra P; Wang, Koon-Hui; Sipes, Brent S; Hooks, Cerruti R R

2010-06-01

186

Effects of soil tillage and management of crop residues on soil properties: abundance, biomass and diversity of earthworms, soil structure and nutrient evolutions  

NASA Astrophysics Data System (ADS)

The living soil is represented by soil biota that interacts with aboveground biota and with the abiotic environment, soil structure, soil reaction, organic matter, nutrient contents, aso. Maintenance of soil organic matter through integrated soil fertility management is an important issue to conciliate soil quality and agricultural productivity. Earthworms are key actors in soil structure formation through the production of casts and the incorporation of soil organic matter in the soil. Research is still needed about the interactive effects of various tillage and crop residue management practices on earthworm populations and physical and chemical properties of soil. To investigate the impacts of two tillage management systems and two cropping systems on earthworm populations, soil structure evolution and nutrient dynamics, we carried out a three years study in an experimental field. The aims of this experimentation, were to assess the effects of the tillage systems (ploughing versus reduced tillage) and the availability of crop residues (export versus no export) on (i) the abundance, biomass and diversity of earthworms, on the soil structure and on the temporal variation of water extractable nutrients and organic carbon. The first results show that tillage management did significantly affect earthworm abundance and biomass. However, crop residue management did not affect abundance, biomass and diversity of earthworms. Regarding soil physical properties, the tillage affected the compaction profiles within the top 30cm. The analysis of nutrient and organic carbon dynamics show divergent trends (decrease of calcium and magnesium, increase of hot water extractable carbon and phosphorus…) but no clear effect of the studied factors could be identified. The question of the initial soil variability raised as a crucial point in the discussion.

lemtiri, Aboulkacem

2013-04-01

187

Towards understanding the effects of crop production practices on soil nitrogen fixation and denitrification  

NASA Astrophysics Data System (ADS)

Soil productivity can be highly influenced by the composition and activity of its microbial communities. Certain crop production practices suppress microbial processes, e.g. nitrogen fixation is suppressed due to excessive application of chemical supplements of N (ammonium, nitrate), whereas removal of nitrogen by denitrification may be enhanced by such conditions. We optimise and use PCR-based techniques to analyse the soil potential for nitrogen fixation and denitrification and seek ways to enhance microbial nitrogen fixation by managing the amount and form of N applied to the soil. These techniques are being optimised for Australian cotton production soils and will also be useful for determining the effects of different crop production strategies on microbial nitrogen cycling in such soils.

Pereg, Lily; McMillan, Mary; Renz, Katrin

2014-05-01

188

Nitrous oxide release from arable soil: Importance of N-fertilization, crops and temporal variation  

Microsoft Academic Search

Throughout 33months nitrous oxide (N2O) release rates were measured from a field experiment comparing crop and N-fertilization treatments laid out on a luvisol derived from loess. Winter wheat, winter barley, winter rape and sugar beet were cultivated using conventional soil management. Each crop was fertilized at three rates of N application (N 1.0: usual, N 0.5: 50% of usual, N

E.-A. Kaiser; K. Kohrs; M. Kücke; E. Schnug; O. Heinemeyer; J. C. Munch

1998-01-01

189

Salt tolerance classification of crops according to soil salinity and to water stress day index  

Microsoft Academic Search

The observations of a long-term experiment on the use of saline water were used to compare the crop tolerance to salinity. Salinity affected significantly yield, evapotranspiration, pre-dawn leaf water potential and stomatal conductance. The higher the salinity, the lower the yield, evapotranspiration, pre-dawn leaf water potential and stomatal resistance. The crop classification, based on soil salinity, corresponds with the classification

N. Katerji; J. W. van Hoorn; A. Hamdy; M. Mastrorilli

2000-01-01

190

Management of lignite fly ash for improving soil fertility and crop productivity.  

PubMed

Lignite fly ash (LFA), being alkaline and endowed with excellent pozzolanic properties, a silt loam texture, and plant nutrients, has the potential to improve soil quality and productivity. Long-term field trials with groundnut, maize, and sun hemp were carried out to study the effect of LFA on growth and yield. Before crop I was sown, LFA was applied at various doses with and without press mud (an organic waste from the sugar industry, used as an amendment and source of nutrients). LFA with and without press mud was also applied before crops III and V were cultivated. Chemical fertilizer, along with gypsum, humic acid, and biofertilizer, was applied in all treatments, including the control. With one-time and repeat applications of LFA (with and without press mud), yield increased significantly (7.0-89.0%) in relation to the control crop. The press mud enhanced the yield (3.0-15.0%) with different LFA applications. The highest yield LFA dose was 200 t/ha for one-time and repeat applications, the maximum yield being with crop III (combination treatment). One-time and repeat application of LFA (alone and in combination with press mud) improved soil quality and the nutrient content of the produce. The highest dose of LFA (200 t/ha) with and without press mud showed the best residual effects (eco-friendly increases in the yield of succeeding crops). Some increase in trace- and heavy-metal contents and in the level of gamma-emitters in soil and crop produce, but well within permissible limits, was observed. Thus, LFA can be used on a large scale to boost soil fertility and productivity with no adverse effects on the soil or crops, which may solve the problem of bulk disposal of fly ash in an eco-friendly manner. PMID:17705037

Ram, Lal C; Srivastava, Nishant K; Jha, Sangeet K; Sinha, Awadhesh K; Masto, Reginald E; Selvi, Vetrivel A

2007-09-01

191

Effect of long-term phosphorus fertilization on soil Se and transfer of soil Se to crops in northern Japan.  

PubMed

Phosphorus (P) fertilizer can potentially serve as a source for Se accumulation in croplands. Furthermore, it has been reported that the addition of P fertilizer to soil may enhance Se availability. Japanese agricultural soils are typically enriched in P as a result of long-term, excessive P fertilization. Therefore, we conducted a three-year field experiment in order to evaluate the effect of P fertilization on the Se content of soils and crops. Potato, wheat and barley were cultivated with and without P fertilization at two field sites in Hokkaido (northern Japan) with different levels of historical P accumulation. The first field site consisted of an Andosol soil with low available P and the second site, a Cambisol soil with high available P. The three years of continuous P fertilization over the course of the experiment did not result in a significant increase in the Se content of soils or plants. The Se content of soils and plants, however, was higher in soil samples from the Cambisol field site than from the Andosol field site, and total soil Se was significantly correlated with available soil P. Soluble soil Se and the soil-plant transfer factor for Se were not affected by P fertilization. Thus, we concluded that the higher plant Se content at the Cambisol field site was primarily due to the higher levels of accumulated Se in the soil at the site and that historical excess P fertilization typical of agricultural soils in Japan contributes to increased Se uptake by crops. PMID:24875865

Altansuvd, Javkhlantuya; Nakamaru, Yasuo M; Kasajima, Shinya; Ito, Hirotake; Yoshida, Hozumi

2014-07-01

192

Simulation of crop yield variability by improved root-soil-interaction modelling  

NASA Astrophysics Data System (ADS)

Understanding the processes and factors that govern the within-field variability in crop yield has attached great importance due to applications in precision agriculture. Crop response to environment at field scale is a complex dynamic process involving the interactions of soil characteristics, weather conditions and crop management. The numerous static factors combined with temporal variations make it very difficult to identify and manage the variability pattern. Therefore, crop simulation models are considered to be useful tools in analyzing separately the effects of change in soil or weather conditions on the spatial variability, in order to identify the cause of yield variability and to quantify the spatial and temporal variation. However, tests showed that usual crop models such as CERES-Wheat and CERES-Maize were not able to quantify the observed within-field yield variability, while their performance on crop growth simulation under more homogeneous and mainly non-limiting conditions was sufficent to simulate average yields at the field-scale. On a study site in South Germany, within-field variability in crop growth has been documented since years. After detailed analysis and classification of the soil patterns, two site specific factors, the plant-available-water and the O2 deficiency, were considered as the main causes of the crop growth variability in this field. Based on our measurement of root distribution in the soil profile, we hypothesize that in our case the insufficiency of the applied crop models to simulate the yield variability can be due to the oversimplification of the involved root models which fail to be sensitive to different soil conditions. In this study, the root growth model described by Jones et al. (1991) was adapted by using data of root distributions in the field and linking the adapted root model to the CERES crop model. The ability of the new root model to increase the sensitivity of the CERES crop models to different enviromental conditions was then evaluated by means of comparison of the simualtion results with measured data and by scenario calculations.

Duan, X.; Gayler, S.; Priesack, E.

2009-04-01

193

Simply Obtained Global Radiation, Soil Temperature and SoilMoisture in an Alley Cropping System in Semi-Arid Kenya  

Microsoft Academic Search

Summary  ?Global radiation, soil temperature and soil moisture data were obtained from a 4–6 year old Cassia siamea\\/maize (CM) alley cropping (or hedgerow intercropping) system, at a semi-arid site at Machakos, Kenya, in the late eighties.\\u000a With the growing need to explore and manage variations in agro-ecosystems these results deserve new attention. They quantify,\\u000a in a simple but detailed manner, the

D. N. Mungai; C. J. Stigter; C. L. Coulson; J. K. Ng’ang’a

2000-01-01

194

Tillage and crop effects on seasonal dynamics of soil CO 2 evolution, water content, temperature, and bulk density  

Microsoft Academic Search

Crop management practices impact soil productivity by altering the soil environment, which in turn affects microbial growth and decomposition processes that transform plant-produced C to soil organic matter (SOM) or CO2. Long-term reduced tillage increases SOM, but little is known about the seasonal dynamics of soil CO2 evolution as affected by tillage and crop. The objectives were as follows: (1)

A. J. Franzluebbers; F. M. Hons; D. A. Zuberer

1995-01-01

195

Soil properties estimation by inversion of a crop model and observations on crops improves the prediction of agro-environmental variables  

Microsoft Academic Search

Using data observed on crop status to inverse a crop model is an interesting way of estimating the soil parameters, which are rather difficult to determine. Nevertheless, the results of parameter estimation depend on the observation set and the results of the predictions made with the model are also affected. The goal of this study is to assess the quality

Hubert Varella; Martine Guérif; Samuel Buis; Nicolas Beaudoin

2010-01-01

196

Optimizing root system architecture in biofuel crops for sustainable energy production and soil carbon sequestration  

PubMed Central

Root system architecture (RSA) describes the dynamic spatial configuration of different types and ages of roots in a plant, which allows adaptation to different environments. Modifications in RSA enhance agronomic traits in crops and have been implicated in soil organic carbon content. Together, these fundamental properties of RSA contribute to the net carbon balance and overall sustainability of biofuels. In this article, we will review recent data supporting carbon sequestration by biofuel crops, highlight current progress in studying RSA, and discuss future opportunities for optimizing RSA for biofuel production and soil carbon sequestration.

To, Jennifer PC; Zhu, Jinming; Benfey, Philip N

2010-01-01

197

Effects of cropping systems on soil organic matter in a pair of conventional and biodynamic mixed cropping farms in Canterbury, New Zealand  

Microsoft Academic Search

Effects of cropping systems on soil organic matter (SOM) in a pair of conventional and biodynamic mixed cropping farms were\\u000a investigated. Soil samples (0–75 and 75–150-mm depths) were analysed for total carbon (TC), total nitrogen (TN), microbial\\u000a biomass C (BC) and microbial biomass N (BN), and sequentially extracted for labile and stable SOM using cold water, hot water,\\u000a acid mixtures

T. Murata; K. M. Goh

1997-01-01

198

Effects of Winter Cover Crops Residue Returning on Soil Enzyme Activities and Soil Microbial Community in Double-Cropping Rice Fields  

PubMed Central

Residue management in cropping systems is useful to improve soil quality. However, the studies on the effects of residue management on the enzyme activities and microbial community of soils in South China are few. Therefore, the effects of incorporating winter cover crop residue with a double-cropping rice (Oryza sativa L.) system on soil enzyme activities and microbial community in Southern China fields were studied. The experiment has conducted at the experimental station of the Institute of Soil and Fertilizer Research, Hunan Academy of Agricultural Science, China since winter 2004. Four winter cropping systems were used: rice–rice–ryegrass (Lolium multiflorum L.) (R-R-Ry), rice–rice–Chinese milk vetch (Astragalus sinicus L.) (R-R-Mv), rice–rice–rape (Brassica napus L.) (R-R-Ra) and rice–rice with winter fallow (R-R-Fa). The result indicated that the enzyme activities in the R-R-Ry, R-R-Mv and R-R-Ra systems were significantly higher (P<0.05) than in the R-R-Fa system during the early and late rice season. The ?-glucosidase activities reached peak values at the tillering stage after residue application, and alkaline phosphatase activities reached peak values at the booting stage after residue application, respectively, the activities of ?-glucosidase and alkaline phosphatase gradually decreased after this. Arylsulfatase activities reached peak values at the maturity stage. Arylamidase activities reached peak values at the maturity stage. The numbers of aerobic bacteria, actinomycete and fungus of residue treatments were significantly higher (P<0.05) than that the R-R-Ra system. However, the number of anaerobic bacteria under the R-R-Ry and R-R-Mv systems was significantly lower (P<0.05) than that under the R-R-Fa system during early rice and late rice growth stage. Thus, incorporation of winter cover crops into rotations may increase enzyme activities and microbial community in soil and therefore improve soil quality.

Hai-Ming, Tang; Xiao-Ping, Xiao; Wen-Guang, Tang; Ye-Chun, Lin; Ke, Wang; Guang-Li, Yang

2014-01-01

199

Effects of winter cover crops residue returning on soil enzyme activities and soil microbial community in double-cropping rice fields.  

PubMed

Residue management in cropping systems is useful to improve soil quality. However, the studies on the effects of residue management on the enzyme activities and microbial community of soils in South China are few. Therefore, the effects of incorporating winter cover crop residue with a double-cropping rice (Oryza sativa L.) system on soil enzyme activities and microbial community in Southern China fields were studied. The experiment has conducted at the experimental station of the Institute of Soil and Fertilizer Research, Hunan Academy of Agricultural Science, China since winter 2004. Four winter cropping systems were used: rice-rice-ryegrass (Lolium multiflorum L.) (R-R-Ry), rice-rice-Chinese milk vetch (Astragalus sinicus L.) (R-R-Mv), rice-rice-rape (Brassica napus L.) (R-R-Ra) and rice-rice with winter fallow (R-R-Fa). The result indicated that the enzyme activities in the R-R-Ry, R-R-Mv and R-R-Ra systems were significantly higher (P<0.05) than in the R-R-Fa system during the early and late rice season. The ?-glucosidase activities reached peak values at the tillering stage after residue application, and alkaline phosphatase activities reached peak values at the booting stage after residue application, respectively, the activities of ?-glucosidase and alkaline phosphatase gradually decreased after this. Arylsulfatase activities reached peak values at the maturity stage. Arylamidase activities reached peak values at the maturity stage. The numbers of aerobic bacteria, actinomycete and fungus of residue treatments were significantly higher (P<0.05) than that the R-R-Ra system. However, the number of anaerobic bacteria under the R-R-Ry and R-R-Mv systems was significantly lower (P<0.05) than that under the R-R-Fa system during early rice and late rice growth stage. Thus, incorporation of winter cover crops into rotations may increase enzyme activities and microbial community in soil and therefore improve soil quality. PMID:24956152

Hai-Ming, Tang; Xiao-Ping, Xiao; Wen-Guang, Tang; Ye-Chun, Lin; Ke, Wang; Guang-Li, Yang

2014-01-01

200

Long-term effects of fallow systems and lengths on crop production and soil fertility maintenance in West Africa  

Microsoft Academic Search

In the development of short fallow systems as alternatives to shifting cultivation in West Africa, a long-term trial was established at the International Institute of Tropical Agriculture (IITA) on an Alfisol in the forest-savanna transitional zone of southwestern Nigeria, comparing three fallow systems; natural regrowth fallow, cover crop fallow and alley cropping on soil productivity and crop yield sustainability. The

G. Tian; B. T. Kang; G. O. Kolawole; P. Idinoba; F. K. Salako

2005-01-01

201

Carbon Supply and Storage in Tilled and Nontilled Soils as Influenced by Cover Crops and Nitrogen Fertilization  

Microsoft Academic Search

Soil carbon (C) sequestration in tilled and nontilled areas can be influenced by crop management practices due to differences in plant C inputs and their rate of mineralization. We examined the influence of four cover crops {legume (hairy vetch (Vicia villosa Roth)), non- legume (rye (Secale cereale L.)), biculture of legume and nonlegume (vetch and rye), and no cover crops

Upendra M. Sainju; Bharat P. Singh; Wayne F. Whitehead; Shirley Wang

2006-01-01

202

Assimilation of AMSR-E Soil Moisture Retrievals into the USDA Global Crop Production Decision Support System  

Microsoft Academic Search

Soil moisture is a fundamental data source used in crop growth stage and crop stress models. The accuracy of these models is highly dependent upon the data sources used; particularly the accuracy, consistency, and spatial and temporal coverage of the land and climatic forcing data. The U. S. Department of Agriculture (USDA) Production Estimates and Crop Assessment Division (PECAD) state

J. Bolten; W. Crow; X. Zhan; T. Jackson; C. Reynolds; B. Doorn

2006-01-01

203

Effects of crop residue on soil and plant water evaporation in a dryland cotton system  

NASA Astrophysics Data System (ADS)

Dryland agricultural cropping systems emphasize sustaining crop yields with limited use of fertilizer while conserving both rain water and the soil. Conservation of these resources may be achieved with management systems that retain residues at the soil surface simultaneously modifying both its energy and water balance. A conservation practice used with cotton grown on erodible soils of the Texas High Plains is to plant cotton into chemically terminated wheat residues. In this study, the partitioning of daily and seasonal evapotranspiration ( E t) into soil and plant water evaporation was compared for a conventional and a terminated-wheat cotton crop using the numerical model ENWATBAL. The model was configured to account for the effects of residue on the radiative fluxes and by introducing an additional resistance to latent and sensible heat fluxes derived from measurements of wind speed and vapor conductance from a soil covered with wheat-stubble. Our results showed that seasonal E t was similar in both systems and that cumulative soil water evaporation was 50% of E t in conventional cotton and 31% of E t in the wheat-stubble cotton. Calculated values of E t were in agreement with measured values. The main benefit of the wheat residues was to suppress soil water evaporation by intercepting irradiance early in the growing season when the crop leaf area index (LAI) was low. In semiarid regions LAI of dryland cotton seldom exceeds 2 and residues can improve water conservation. Measured soil temperatures showed that early in the season residues reduced temperature at 0.1 m depth by as much as 5°C and that differences between systems diminished with depth and over time. Residues increased lint yield per unit of E t while not modifying seasonal E t and reducing cumulative soil water evaporation.

Lascano, R. J.; Baumhardt, R. L.

1996-03-01

204

Determination of potential management zones from soil electrical conductivity, yield and crop data*  

PubMed Central

One approach to apply precision agriculture to optimize crop production and environmental quality is identifying management zones. In this paper, the variables of soil electrical conductivity (EC) data, cotton yield data and normalized difference vegetation index (NDVI) data in an about 15 ha field in a coastal saline land were selected as data resources, and their spatial variabilities were firstly analyzed and spatial distribution maps constructed with geostatistics technique. Then fuzzy c-means clustering algorithm was used to define management zones, fuzzy performance index (FPI) and normalized classification entropy (NCE) were used to determine the optimal cluster numbers. Finally one-way variance analysis was performed on 224 georeferenced soil and yield sampling points to assess how well the defined management zones reflected the soil properties and productivity level. The results reveal that the optimal number of management zones for the present study area was 3 and the defined management zones provided a better description of soil properties and yield variation. Statistical analyses indicate significant differences between the chemical properties of soil samples and crop yield in each management zone, and management zone 3 presented the highest nutrient level and potential crop productivity, whereas management zone 1 the lowest. Based on these findings, we conclude that fuzzy c-means clustering approach can be used to delineate management zones by using the given three variables in the coastal saline soils, and the defined management zones form an objective basis for targeting soil samples for nutrient analysis and development of site-specific application strategies.

Li, Yan; Shi, Zhou; Wu, Ci-fang; Li, Hong-yi; Li, Feng

2008-01-01

205

Soil, crop and emission responses to seasonal-controlled traffic in organic vegetable farming on loam soil  

Microsoft Academic Search

Some organic arable and vegetable farms in the Netherlands use cm-precise guidance of machinery to restrict wheel traffic to fixed traffic lanes and to achieve non-trafficked cropping zones with optimized soil structure in between the lanes. Contrary to controlled traffic farming (CTF) the traffic lanes are not yet used for harvesting and primary tillage. Therefore, the system is called a

G. D. Vermeulen; J. Mosquera

2009-01-01

206

Parameter Estimation for a crop model: separate and joint calibration of soil and plant parameters  

NASA Astrophysics Data System (ADS)

Vegetation plays a major role both in the atmospheric and terrestrial water cycle. A great deal of vegetation cover in the developed world consists of agricultural used land (i.e. 44 % of the territory of the EU). Therefore, crop models have become increasingly prominent for studying the impact of Global Change both on economic welfare as well as on influence of vegetation on climate, and feedbacks with hydrological processes. By doing so, it is implied that crop models properly reflect the soil water balance and vertical exchange with the atmosphere. Although crop models can be incorporated in Surface Vegetation Atmosphere Transfer Schemes for that purpose, their main focus has traditionally not been on predicting water and energy fluxes, but yield. In this research we use data from two lysimeters in Brandis (Saxony, Germany), which have been planted with the crops of the surrounding farm, to test the capability of the crop model in SWAP. The lysimeters contain different natural soil cores, leading to substantially different yield. This experiment gives the opportunity to test, if the crop model is portable - that is if a calibrated crop can be moved between different locations. When using the default parameters for the respective environment, the model does neither quantitatively nor qualitatively reproduce the difference in yield and LAI for the different lysimeters. The separate calibration of soil and plant parameter was poor compared to the joint calibration of plant and soil parameters. This suggests that the model is not portable, but needs to be calibrated for individual locations, based on measurements or expert knowledge.

Hildebrandt, A.; Jackisch, C.; Luis, S.

2008-12-01

207

Global scale DAYCENT model analysis of greenhouse gas emissions and mitigation strategies for cropped soils  

NASA Astrophysics Data System (ADS)

Conversion of native vegetation to cropland and intensification of agriculture typically result in increased greenhouse gas (GHG) emissions (mainly N 2O and CH 4) and more NO 3 leached below the root zone and into waterways. Agricultural soils are often a source but can also be a sink of CO 2. Regional and larger scale estimates of GHG emissions are usually obtained using IPCC emission factor methodology, which is associated with high uncertainty. To more realistically represent GHG emissions we used the DAYCENT biogeochemical model for non-rice major crop types (corn, wheat, soybean). IPCC methodology estimates N losses from croplands based solely on N inputs. In contrast, DAYCENT accounts for soil class, daily weather, historical vegetation cover, and land management practices such as crop type, fertilizer additions, and cultivation events. Global datasets of weather, soils, native vegetation, and cropping fractions were mapped to a 1.9° × 1.9° resolution. Non-spatial data (e.g., rates and dates of fertilizer applications) were assumed to be identical within crop types across regions. We compared model generated baseline GHG emissions and N losses for irrigated and rainfed cropping with land management alternatives intended to mitigate GHG emissions. Reduced fertilizer resulted in lower N losses, but crop yields were reduced by a similar proportion. Use of nitrification inhibitors and split fertilizer applications both led to increased (~ 6%) crop yields but the inhibitor led to a larger reduction in N losses (~ 10%). No-till cultivation, which led to C storage, combined with nitrification inhibitors, resulted in reduced GHG emissions of ~ 50% and increased crop yields of ~ 7%.

Del Grosso, Stephen J.; Ojima, Dennis S.; Parton, William J.; Stehfest, Elke; Heistemann, Maik; DeAngelo, Benjamin; Rose, Steven

2009-05-01

208

Tillage intensity effects on soil properties and crop yields in a long-term trial on morainic loam soil in southeast Norway  

Microsoft Academic Search

Many tillage studies focus primarily on grain crops, whereas other important agricultural crops receive little attention. This paper presents yield results for various crops grown in the tenth to sixteenth year of a long-term tillage trial on loam soil in southeast Norway. Traditional plough tillage was compared with deep and shallow tine cultivation and with minimum tillage, and the residual

E. Ekeberg; H. C. F. Riley

1997-01-01

209

Arsenic, boron, molybdenum, and selenium in successive cuttings of forage crops field grown on fly ash amended soil  

Microsoft Academic Search

Alfalfa, birdsfoot trefoil, brome, orchard grass, and timothy were grown on soil amended with 112.5 metric tons per hectare of coal fly ash and untreated soil. Five successive cuttings of each crop were analyzed for arsenic, boron, molybdenum, and selenium. Of the fly ash treated crops boron showed a consistent increase mainly in the legumes, while selenium increased mainly in

Walter H. Gutenmann; Irene S. Pakkala; Dorothy J. Churey; William C. Kelly; Donald J. Lisk

1979-01-01

210

Burning, tillage and herbicide effects on the soil microflora in a wheat-soybean double-crop system  

Microsoft Academic Search

As sustainable crop management systems are developed, an assessement of the effects of these practices on the soil microflora is essential to ensure maximum productivity. A 3-year field study was established to determine the effects of crop residue burning, no-till management and four preemergence herbicides on soil microorganisms. Numbers of actinomycetes, algae, bacteria, fungi and nitrifiers were evaluated during the

Pamela A. Harris; Harry H. Schomberg; Philip A. Banks; Joel Giddens

1995-01-01

211

Cover crops and cultivation: Impacts on soil N dynamics and microbiological function in a Mediterranean vineyard agroecosystem  

Microsoft Academic Search

Impacts of cover crops, tillage and abiotic factors on soil nitrogen (N) dynamics, greenhouse gas emissions, and microbiological functions were investigated in a vineyard in California's Mediterranean climate. Treatments had been established in fall 2001 and were composed of two cover crops [Trios 102 (Triticale×Triosecale), (‘Trios’), Merced Rye (Secale cereale), (‘Rye’)] and cultivation (‘Cultivation’). Soils were sampled every 2–3 weeks

Kerri Steenwerth; K. M. Belina

2008-01-01

212

Recycling of organic matter through mulch in relation to chemical and microbiological properties of soil and crop yields  

Microsoft Academic Search

Summary Field experiments were conducted to investigate the effect of organic mulching on the nutrient status, microbiological properties and the yield of maize and green gram crops. Soil organic carbon and humin and humus carbon of the fallow and the cropped soils were augmented by mulching. More of nitrogen, available phosphorus and ammoniacal and nitrate nitrogen were found in mulched

A. C. Gaur; D. Mukherjee

1980-01-01

213

Use of compost to improve soil properties and crop productivity under low input agricultural system in West Africa  

Microsoft Academic Search

Lack of adequate nutrient supply and poor soil structure are the principal constraints to crop production under low input agriculture systems of West Africa. Experiments at two sites (Mediga and Yimtenga) were conducted in Burkina Faso to assess the impact of compost on improving crop production and soil properties. In the first experiment, compost was applied at the rate of

E. Ouédraogo; A. Mando; N. P. Zombré

2001-01-01

214

Preliminary Analysis of First Crop of Plants Grown in Seven Soils Uniformly Contaminated with Four Transuranic Elements Simultaneously.  

National Technical Information Service (NTIS)

A forage crop and a grain crop of wheat were harvested from a replicated experiment with about 200 kg soil per container in which seven soils from different locations throughout the U.S.A. were spiked with four different transuranic elements simultaneousl...

A. Wallace E. M. Romney H. Nishita E. K. Schultz

1979-01-01

215

Persistence of Mycobacterium avium subsp. paratuberculosis in soil, crops, and ensiled feed following manure spreading on infected dairy farms  

PubMed Central

The goal of this study was to determine the persistence of Mycobacterium avium subsp. paratuberculosis (MAP) in soil, crops, and ensiled feeds following manure spreading. This bacterium was often found in soil samples, but less frequently in harvested feeds and silage. Spreading of manure on fields used for crop harvest is preferred to spreading on grazing pastures.

Fecteau, Marie-Eve; Hovingh, Ernest; Whitlock, Robert H.; Sweeney, Raymond W.

2013-01-01

216

Water-saving ground cover rice production system reduces net greenhouse gas fluxes in an annual rice-based cropping system  

NASA Astrophysics Data System (ADS)

To safeguard food security and preserve precious water resources, the technology of water-saving ground cover rice production system (GCRPS) is being increasingly adopted for the rice cultivation. However, changes in soil water status and temperature under GCRPS may affect soil biogeochemical processes that control the biosphere-atmosphere exchanges of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). The overall goal of this study is to better understand how net ecosystem greenhouse gas exchanges (NEGE) and grain yields are affected by GCRPS in an annual rice-based cropping system. Our evaluation was based on measurements of the CH4 and N2O fluxes and soil heterotrophic respiration (CO2 emission) over a complete year, as well as the estimated soil carbon sequestration intensity for six different fertilizer treatments for conventional paddy and GCRPS. The fertilizer treatments included urea application and no N fertilization for both conventional paddy (CUN and CNN) and GCRPS (GUN and GNN), solely chicken manure (GCM) and combined urea and chicken manure applications (GUM) for GCRPS. Averaging across all the fertilizer treatments, GCRPS increased annual N2O emission and grain yield by 40% and 9%, respectively, and decreased annual CH4 emission by 69%, while GCRPS did not affect soil CO2 emissions relative to the conventional paddy. The annual direct emission factors of N2O were 4.01, 0.087 and 0.50% for GUN, GCM and GUM, respectively, and 1.52% for the conventional paddy (CUN). The annual soil carbon sequestration intensity under GCRPS was estimated to be an average of -1.33 Mg C ha-1 yr-1, which is approximately 44% higher than the conventional paddy. The annual NEGE were 10.80-11.02 Mg CO2-eq ha-1 yr-1 for the conventional paddy and 3.05-9.37 Mg CO2-eq ha-1 yr-1 for the GCRPS, suggesting the potential feasibility of GCRPS in reducing net greenhouse effect from rice cultivation. Using organic fertilizers for GCRPS considerably reduced annual emissions of CH4 and N2O and increased soil carbon sequestration, resulting in the lowest NEGE (3.05-5.00 Mg CO2-eq ha-1 yr-1). Accordingly, water-saving GCRPS with organic fertilizer amendments was considered the most promising management regime for simultaneously achieving relatively high grain yield and reduced net greenhouse gas emission.

Yao, Z.; Du, Y.; Tao, Y.; Zheng, X.; Liu, C.; Lin, S.; Butterbach-Bahl, K.

2014-06-01

217

Soil respiration at mean annual temperature predicts annual total across vegetation types and biomes.  

PubMed

Soil respiration (SR) constitutes the largest flux of CO(2) from terrestrial ecosystems to the atmosphere. However, there still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 80 site-years for 57 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SR(MAT)), irrespective of the type of ecosystem and biome. This is theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q(10)). We further show that for seasonally dry sites where annual precipitation (P) is lower than potential evapotranspiration (PET), annual SR can be predicted from wet season SR(MAT) corrected for a factor related to P/PET. Our finding indicates that it can be sufficient to measure SR(MAT) for obtaining a well constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution of soil CO(2) emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatial resolution of a major component of the global carbon cycle. PMID:23293656

Bahn, M; Reichstein, M; Davidson, E A; Grünzweig, J; Jung, M; Carbone, M S; Epron, D; Misson, L; Nouvellon, Y; Roupsard, O; Savage, K; Trumbore, S E; Gimeno, C; Yuste, J Curiel; Tang, J; Vargas, R; Janssens, I A

2010-07-01

218

Plant uptake and in-soil degradation of PCB-5 under varying cropping conditions.  

PubMed

A 60-d greenhouse experiment was conducted to investigate the uptake and in-soil degradation of PCB-5 under single cropping and intercropping conditions involving three crop plant species: pumpkin, soybean and corn. Volatilization of PCB-5 from the soil surface was also tested. The results show that while uptake of PCB-5 by the test plant species is possible and the root concentration of PCB-5 had a control on the upward transport of PCB-5 to the above-ground portion of the plants, the PCB-5 extracted by the plants mainly accumulated in the root materials. Phytoextraction contributed insignificantly toward the loss of the soil-borne PCB-5. Volatilization of PCB-5 from the soil was recorded but it appeared that this did not result in a marked loss of PCB-5 in the bulk soil though it might cause remarkable removal of PCB-5 in a thin layer of the topsoil (1 mm). It is likely that the in-soil biodegradation contributed markedly to the observed reduction in soil-borne PCB-5. The in-soil biodegradation of PCB-5 was significantly enhanced under intercropping conditions, which appeared to be related to increased microbial activities, particularly bacterial activities. The soil residual PCB-5 was correlated with the activity of the following enzymes: catalase (CAT), polyphenol oxidase (PPO) and peroxidase (POD). PMID:21724228

Li, Huashou; Liu, Longyuan; Lin, Chuxia; Wang, Shaorui

2011-08-01

219

Mapping Surface Soil Organic Carbon for Crop Fields with Remote Sensing  

NASA Technical Reports Server (NTRS)

The organic C concentration of surface soil can be used in agricultural fields to vary crop production inputs. Organic C is often highly spatially variable, so that maps of soil organic C can be used to vary crop production inputs using precision farming technology. The objective of this research was to demonstrate the feasibility of mapping soil organic C on three fields, using remotely sensed images of the fields with a bare surface. Enough soil samples covering the range in soil organic C must be taken from each field to develop a satisfactory relationship between soil organic C content and image reflectance values. The number of soil samples analyzed in the three fields varied from 22 to 26. The regression equations differed between fields, but gave highly significant relationships with R2 values of 0.93, 0.95, and 0.89 for the three fields. A comparison of predicted and measured values of soil organic C for an independent set of 2 soil samples taken on one of the fields gave highly satisfactory results, with a comparison equation of % organic C measured + 1.02% organic C predicted, with r2 = 0.87.

Chen, Feng; Kissel, David E.; West, Larry T.; Rickman, Doug; Luvall, J. C.; Adkins, Wayne

2004-01-01

220

The impact of long-term nitrogen fertilizer applications on soil organic carbon in a dryland cereal cropping system of the Loess Plateau  

NASA Astrophysics Data System (ADS)

Concerns over food security and global climate change require an improved understanding of how to achieve optimal crop yields whilst minimizing net greenhouse gas emissions from agriculture. In the semi-arid Loess Plateau region of China, as elsewhere, fertilizer nitrogen (N) inputs are necessary to increase yields and improve local food security. In a dryland annual cropping system, we evaluated the effects of N fertilizers on crop yield, its long term impact on soil organic carbon (SOC) concentrations and stock sizes, and the distribution of carbon (C) within various aggregate-size fractions. A current version (RothC) of the Rothamsted model for the turnover of organic C in soil was used to simulate SOC measurements. Five N application rates [0 (N0), 45 (N45), 90 (N90), 135 (N135), and 180 (N180) kg N ha-1] were applied to plots for 25 years (1984-2009) on a loam soil (Cumulic Haplustoll) at the Changwu State Key Agro-Ecological Experimental Station, Shaanxi, China. Crop yield varied with year, but increased over time in the fertilized plots. Average annual grain yields were 1.15, 2.46, 3.11, 3.49, and 3.55 Mg ha-1 with the increasing N application rates, respectively. Long-term N fertilizer application significantly (P<0.05) increased SOC concentrations and stocks in the 0-20 cm horizon. Using RothC, the calculated annual inputs of plant C (in roots, stubble, root exudates, etc.) to the soil were 0.61, 0.74, 0.78, 0.86, and 0.97 t C ha-1 year-1 in N0, N45, N90, N135 and N180 treatments, respectively. The modeled turnover time of SOC (excluding inert organic C) in the continuous wheat cropping system was 26 years. The SOC accumulation rate was estimated to be 40.0, 48.0, 68.0, and 100.0 kg C ha-1 year-1 for the N45, N90, N135 and N180 treatments over 25 years, respectively. As aboveground biomass was removed, the increases in SOC stocks with higher N application are attributed to increased inputs of root biomass and root exudates. Increasing N application rates significantly improved C concentrations in the macroaggregate fractions (>1 mm). The increase in SOC with N fertilizer applications contributed to improved soil quality as well as crop productivity.

Guo, S.

2011-12-01

221

INFLUENCE OF TWENTY-THREE ANNUAL APPLICATIONS OF NITROGEN AND SULFUR FERTILIZERS, AND ONE-TIME LIMING ON DRY MATTER YIELD OF GRASS AND SOME SOIL PROPERTIES ON A DARK GRAY CHERNOZEM SOIL  

Microsoft Academic Search

Most soils in the Prairie Provinces of Canada are deficient in plant-available nitrogen (N), and many soils in the Parkland region also contain insufficient amounts of plant-available sulfur (S) for high crop production. A field experiment with perennial grass stand was conducted to determine the effects of long-term annual N (112 kg N ha), S (11 kg S ha) and

S. S. Malhi; M. Nyborg; E. Solberg; Zhao-Hui Wang; B. Henriquez

2011-01-01

222

Soil microbial activity, aggregation and nutrient responses to straw pulping liquor in corn cropping  

Microsoft Academic Search

The cereal and grass seed cropping systems of the Pacific northwestern USA generate a valuable fiber source for papermaking.\\u000a Pulping straw with KOH produces black liquor, an organic waste effluent with potential as a K source and soil amendment. The\\u000a objectives of this study were to determine if black liquor from wheat straw pulping with KOH improves soil quality including

C. Xiao; R. Stevens; M. Fauci; R. Bolton; M. Lewis; W. T. McKean; D. F. Bezdicek; W. L. Pan

2007-01-01

223

Cover crops alter phosphorus soil fractions and organic matter accumulation in a Peruvian cacao agroforestry system  

Microsoft Academic Search

In many tropical soils, excessive weathering of primary minerals confounded by intense agricultural production has resulted\\u000a in the depletion of organic matter and plant available forms of phosphorus (P). Long-term growth of cover crops in tropical\\u000a agroforestry systems have been shown to influence nutrient cycling, and soil organic matter pools. The objective of this experiment\\u000a was to assess the affect

Hollie Hall; Yuncong Li; Nicholas Comerford; Enrique Arévalo Gardini; Luis Zuniga Cernades; Virupax Baligar; Hugh Popenoe

2010-01-01

224

Properties of compacted fine-textured soils as affected by crop rotation and reduced tillage  

Microsoft Academic Search

The effects of crop rotation and reduced tillage on physical properties of compacted soil were investigated in field experiments on two fine-textured soils. Field experiments were established in 1990 when trial plots were compacted to 0.45–0.50m depth by three passes with high axle load traffic. Control plots were not loaded. Both compacted (CO) and control (NC) plots were then ploughed

Laura Alakukku

1998-01-01

225

PHYTOEXTRACTION OF Pb AND Cd FROM A SUPERFUND SOIL: EFFECTS OF AMENDMENTS AND CROPPINGS  

Microsoft Academic Search

In a growth chamber, maize (Zea mays) and Indian mustard (Brassica juncea) were grown over two croppings in soil from a Superfund site (PbTotal = 65,200 mg\\/kg and CdTotal = 52 mg\\/kg). Soil treatments consisted of ethylenediaminetetraacetic acid, sodium citrate and composted sewage sludge, each at two rates (EDTA .05%, EDTA .2%, citrate .05%, citrate .2%, CSS 5% and CSS

Timothy J. Bricker; John Pichtel; Hugh J. Brown; Misty Simmons

2001-01-01

226

Soil temperature in a sugar-cane crop as a function of the management system  

Microsoft Academic Search

Air and soil temperatures are, by far, the most important state variables of agroecosystems. In the case of sugar-cane (Saccharum officinarum L.) they affect plant development, maturation and a series of biological and physical-chemical soil processes. This paper presents a comparative study of three management practices, applied to the first ratoon of a sugar-cane crop established on a Rhodic Kandiudox

J. C. M. Oliveira; L. C. Timm; T. T. Tominaga; F. A. M. Cássaro; K. Reichardt; O. O. S. Bacchi; D. Dourado-Neto; G. M. de S. Câmara

2001-01-01

227

Soil microbial biomass carbon and nitrogen as affected by cropping systems  

Microsoft Academic Search

The impacts of crop rotations and N fertilization on microbial biomass C (Cmic) and N (Nmic) were studied in soils of two long-term field experiments initiated in 1978 at the Northeast Research Center (NERC) and in\\u000a 1954 at the Clarion-Webster Research Center (CWRC), both in Iowa. Surface soil samples were taken in 1996 and 1997 from plots\\u000a of corn (Zea

J. M. Moore; S. Klose; M. A. Tabatabai

2000-01-01

228

Phosphorus Mass Balances for Successive Crops of Fertilised Rainfed Rice on a Sandy Lowland Soil  

Microsoft Academic Search

Raising and sustaining rice yields in the rainfed lowlands requires an understanding of nutrient inputs and outputs. On sandy\\u000a lowland rice soils, managing phosphorus (P) supply is a key factor in achieving increased yields and sustainable production.\\u000a Phosphorus inputs, rice yields, and crop P uptake were used to quantify P requirements of rice: together with results on soil\\u000a P fractions,

Sovuthy Pheav; R. W. Bell; P. F. White; G. J. D. Kirk

2005-01-01

229

How do soil physical conditions for crop growth vary over time under established contrasting tillage regimes?  

NASA Astrophysics Data System (ADS)

When plant breeders develop modern cereal varieties for the sustainable intensification of agriculture, insufficient thought is given to the impact of tillage on soil physical conditions for crop production. In earlier work, we demonstrated that barley varieties that perform best in ploughed soil (the approach traditionally used for breeding trials) were not the same as those performing best under shallow non-inversion or zero-tillage. We also found that the Quantitative Trait Loci (QTL) associated with improved phosphorus uptake, and hence useful for marker assisted breeding, were not robust between different tillage regimes. The impact of the soil environment had greater impact than the genetics in GxE interactions. It is obvious that soil tillage should be considered when breeding the next generation of crops. Tillage may also have important impacts on carbon storage, but we found that despite greater soil carbon at shallow depths under non-inversion tillage, the carbon stored throughout the soil profile was not affected by tillage. Studies on soil tillage impacts to crop productivity and soil quality are often performed in one season, on single sites that have had insufficient time to develop. Our current research explores multiple sites, on different soils, with temporal measurements of soil physical conditions under contrasting tillage regimes. We use the oldest established contemporary tillage experiments in the United Kingdom, with all sites sharing ploughed and shallow (7cm) non-inversion tillage treatments. In eastern Scotland (Mid Pilmore), the site also has zero tillage and deep ploughing (40 cm) treatments, and was established 11 years ago. In east England there are two sites, both also having a deep non-inversion tillage treatment, and they were established 6 (New Farm Systems) and 8 (STAR) years ago. We measure a range of crop and soil properties at sowing, one month after sowing and post-harvest, including rapid lab based assays that allow high-throughput. Samples are taken over the rooting zone in the topsoil, plough pan and subsoil. The first year's dataset from this comprehensive project will be presented. Early data identified plough pans under shallow non-inversion tillage that will limit root growth at all sites. Aggregate stabilities vary as expected, with plough soils at shallow depth being less stable than non-inversion tillage, but greater stability in plough soils at greater depth due to incorporated organic matter. Very rapidly following cultivation, the seedbeds coalesce, resulting in a more challenging physical environment for crop growth. We are exploring the mechanisms in soil structure temporal dynamics in greater detail, including the resilience of seedbeds to structural degradation through natural weathering and the action of plants. These profound differences in soil conditions will impact the root ideotype of crops for these different conditions. This has implications for the way in which breeding and genotype selection is performed in the future. Ultimately, we aim to identify crop varieties suited to local soil conditions and management, possibly with root traits that boost yields and soil physical quality.

Hallett, Paul; Stobart, Ron; Valentine, Tracy; George, Timothy; Morris, Nathan; Newton, Adrian; McKenzie, Blair

2014-05-01

230

Diversity of Rhizosphere Soil Arbuscular Mycorrhizal Fungi in Various Soybean Cultivars under Different Continuous Cropping Regimes  

PubMed Central

Recent studies have shown that continuous cropping in soybean causes substantial changes to the microbial community in rhizosphere soil. In this study, we investigated the effects of continuous cropping for various time periods on the diversity of rhizosphere soil arbuscular mycorrhizal (AM) fungi in various soybean cultivars at the branching stage. The soybean cultivars Heinong 37 (an intermediate cultivar), Heinong 44 (a high-fat cultivar) and Heinong 48 (a high-protein cultivar) were seeded in a field and continuously cropped for two or three years. We analyzed the diversity of rhizosphere soil AM fungi of these soybean plants at the branching stage using morphological and denaturing gradient gel electrophoresis (DGGE) techniques. The clustering analysis of unweighted pair-group method with arithmetic averages (UPGMA) was then used to investigate the AM fungal community shifts. The results showed that increasing the number of years of continuous cropping can improve the colonization rate of AM fungi in different soybean cultivars at the branching stage. The dominant AM fungi in the experimental fields were Funneliformismosseae and Glomus spp. The number of years of continuous cropping and the soybean cultivar both had obvious effects on the diversity of AM fungi, which was consistent with the results of colonization rate analysis. This study establishes a basis for screening dominant AM fungi of soybean. In addition, the results of this study may be useful for the development of AM fungal inoculants.

Jie, Weiguang; Liu, Xiaorui; Cai, Baiyan

2013-01-01

231

Identification of "ever-cropped" land (1984-2010) using Landsat annual maximum NDVI image composites: Southwestern Kansas case study  

PubMed Central

A time series of 230 intra- and inter-annual Landsat Thematic Mapper images was used to identify land that was ever cropped during the years 1984 through 2010 for a five county region in southwestern Kansas. Annual maximum Normalized Difference Vegetation Index (NDVI) image composites (NDVIann-max) were used to evaluate the inter-annual dynamics of cropped and non-cropped land. Three feature images were derived from the 27-year NDVIann-max image time series and used in the classification: 1) maximum NDVI value that occurred over the entire 27 year time span (NDVImax), 2) standard deviation of the annual maximum NDVI values for all years (NDVIsd), and 3) standard deviation of the annual maximum NDVI values for years 1984–1986 (NDVIsd84-86) to improve Conservation Reserve Program land discrimination. Results of the classification were compared to three reference data sets: County-level USDA Census records (1982–2007) and two digital land cover maps (Kansas 2005 and USGS Trends Program maps (1986–2000)). Area of ever-cropped land for the five counties was on average 11.8 % higher than the area estimated from Census records. Overall agreement between the ever-cropped land map and the 2005 Kansas map was 91.9% and 97.2% for the Trends maps. Converting the intra-annual Landsat data set to a single annual maximum NDVI image composite considerably reduced the data set size, eliminated clouds and cloud-shadow affects, yet maintained information important for discriminating cropped land. Our results suggest that Landsat annual maximum NDVI image composites will be useful for characterizing land use and land cover change for many applications.

Maxwell, Susan K.; Sylvester, Kenneth M.

2012-01-01

232

Identification of "ever-cropped" land (1984-2010) using Landsat annual maximum NDVI image composites: Southwestern Kansas case study.  

PubMed

A time series of 230 intra- and inter-annual Landsat Thematic Mapper images was used to identify land that was ever cropped during the years 1984 through 2010 for a five county region in southwestern Kansas. Annual maximum Normalized Difference Vegetation Index (NDVI) image composites (NDVI(ann-max)) were used to evaluate the inter-annual dynamics of cropped and non-cropped land. Three feature images were derived from the 27-year NDVI(ann-max) image time series and used in the classification: 1) maximum NDVI value that occurred over the entire 27 year time span (NDVI(max)), 2) standard deviation of the annual maximum NDVI values for all years (NDVI(sd)), and 3) standard deviation of the annual maximum NDVI values for years 1984-1986 (NDVI(sd84-86)) to improve Conservation Reserve Program land discrimination.Results of the classification were compared to three reference data sets: County-level USDA Census records (1982-2007) and two digital land cover maps (Kansas 2005 and USGS Trends Program maps (1986-2000)). Area of ever-cropped land for the five counties was on average 11.8 % higher than the area estimated from Census records. Overall agreement between the ever-cropped land map and the 2005 Kansas map was 91.9% and 97.2% for the Trends maps. Converting the intra-annual Landsat data set to a single annual maximum NDVI image composite considerably reduced the data set size, eliminated clouds and cloud-shadow affects, yet maintained information important for discriminating cropped land. Our results suggest that Landsat annual maximum NDVI image composites will be useful for characterizing land use and land cover change for many applications. PMID:22423150

Maxwell, Susan K; Sylvester, Kenneth M

2012-06-01

233

Phytoextraction of Pb and Cd from a superfund soil: effects of amendments and croppings.  

PubMed

In a growth chamber, maize (Zea mays) and Indian mustard (Brassica juncea) were grown over two croppings in soil from a Superfund site (PbTotal = 65,200 mg/kg and CdTotal = 52mg/kg). Soil treatments consisted of ethylenediaminetetraacetic acid, sodium citrate and composted sewage sludge, each at two rates (EDTA .05%, EDTA .2%, citrate .05%, citrate .2%, CSS 5% and CSS 10%, respectively). In most cases, the EDTA and citrate treatments were superior in terms of solubilizing soil Pb for root uptake and translocation into above-ground biomass. In the first maize crop, the EDTA .2% treatment resulted in 2,435 and 9,389mg/kg Pb in shoot and root tissues, respectively. The CSS treatments typically resulted in lowest Pb and Cd removal efficiencies. Lead remaining in the soil after two croppings was mainly associated with the carbonate, organic, and residual fractions, which represent the less bioavailable forms. Soil Cd was generally more mobile for plant uptake than soil Pb. The EDTA .2% and citrate treatments were most successful in promoting Cd uptake by both maize and mustard. Although Pb concentrations (mg/kg tissue) were lower for maize than mustard, the former removed more total Pb (0.2 mg per pot, mean over all treatments), compared to mustard (0.03 mg), by virtue of its higher biomass production. PMID:11688677

Bricker, T J; Pichtel, J; Brown, H J; Simmons, M

2001-01-01

234

Enzyme dynamics in paddy soils of the rice district (NE Italy) under different cropping patterns  

NASA Astrophysics Data System (ADS)

The recent widespread interest on soil enzymes is due to the need to develop sensitive indicators of soil quality that reflect the effects of land management on soil and assist land managers in promoting long-term sustainability of terrestrial ecosystems. The activities of six important enzymes involved in C, N, P, and S cycling were investigated in a paddy soil from the Veneto region, Italy, in four different rotation systems (rice-rice-rice: R-R-R; soya-rice-rice: S-R-R; fallow-rice: F-R; pea-soya-rice: P-S-R) with three replications in April (after field preparation, field moist condition), June (after seedling, waterlogged soil condition), August (after tillering stage of rice, waterlogged soil condition) and October (after rice harvesting, drained soil condition) over the 2012 growing season. Our results demonstrated that enzyme activities varied with rotation systems and growth stages in paddy soil. Compared with field moist soil, drained soil condition resulted in a significant increase (P < 0.05) of ?-glucosidase, arylsulfatase, alkaline and acid phosphatases, leucine aminopeptidase (except of fallow-rice), and chitinase activities in all rotations, while compared with drained soil, early waterlogging (in month of June) significantly decreased (P moist soil> late waterlogged>early waterlogged. There was an inhibitory effect of waterlogging (except P-S-R rotation) for both alkaline and acid phosphatases due to high pH and redox conditions. However, the response of enzymes to waterlogging differed with the chemical species and the cropping pattern. The best rotation system for chitinase, leucine aminopeptidase and ?-glucosidase activity (C and N cycles) proved R-R-R, while for arylsulfatase, alkaline and acid phosphatases (P and S cycles) it was the S-R-R. Key Words: enzyme activity, paddy soil, Crop Rotation System, Italy __ Corresponding Author: Mandana Nadimi-Goki, Tel.: +39 3891356251 E-mail address: mandy.nadimi@gmail.com

Bini, Claudio; Nadimi-Goki, Mandana; Kato, Yoichi; Fornasier, Flavio; Wahsha, Mohammad; Spiandorello, Massimo

2014-05-01

235

Effects of three species of Chihuahuan Desert ants on annual plants and soil properties  

Microsoft Academic Search

We tested the hypothesis that ant species, which occupy the same nest for a decade or longer, would modify nest soils by increasing soil nutrients and microorganisms resulting in increased biomass, density, cover and species richness of annual plants. We measured soil properties and annual plants on nest soils of three species of Chihuahuan Desert ants (Pogonomyrmex rugosus—seed harvester, Aphaenogaster

W. G. Whitford; G. Barness; Y. Steinberger

2008-01-01

236

Effects of wheat cover crop desiccation times on soil physical properties and early growth of corn under no-till and conventional tillage systems  

Microsoft Academic Search

Cover crops can improve soil physical properties but can present challenges for subsequent cash crop growth. The objectives of this research were to investigate the influence of a winter wheat (Triticum aestivum) cover crop on selected soil physical properties and early development of corn in a corn (Zea mays)-soybean (Glycine max) crop rotation. The measurements were conducted on two Indiana

Bojan Stipesevic

2003-01-01

237

Soil Carbon Changes in Transitional Grain Crop Production Systems in South Dakota  

NASA Astrophysics Data System (ADS)

Corn-C (Zea Mays L.), soybean-S (Glycine max L.) and spring wheat-W (Triticum aestivum L.) crops were seeded as a component of either a C-S, S-W, or C-S-W crop rotation on silt-loam textured soils ranging from 3.0-5.0% organic matter. Conservation tillage(chisel plow-field cultivator) was applied to half of the plots. The other plots were direct seeded as a no-till (zero-tillage) treatment. Grain yield and surface crop residues were weighed from each treatment plot. Crop residue (stover and straw) was removed from half of the plots. After four years, soil samples were removed at various increments of depth and soil organic carbon (C) and nitrogen (N) was measured. The ranking of crop residue weights occurred by the order corn>>soybean>wheat. Surface residue accumulation was also greatest with residue treatments that were returned to the plots, those rotations in which maize was a component, and those without tillage. Mean soil organic carbon levels in the 0-7.5cm depth decreased from 3.41% to 3.19% (- 0.22%) with conventional tillage (chisel plow/field cultivator) as compared to a decrease from 3.19% to 3.05% (-0.14%) in plots without tillage over a four year period. Organic carbon in the 0-7.5cm depth decreased from 3.21% to 3.01% (- 0.20%) after residue removed as compared to a decrease from 3.39% to 3.23% (-0.17%) in plots without tillage applied after four years. The soil C:N ratio (0-7.5cm) decreased from 10.63 to 10.37 (-0.26 (unitless)) in the tilled plots over a four-year period. Soil C:N ratio at the 0-7.5cm depth decreased from 10.72 to 10.04 (-0.68) in the no-till plots over a four year period. Differences in the soil C:N ratio comparing residue removed and residue returned were similar (-0.51 vs. -0.43 respectively). These soils are highly buffered for organic carbon changes. Many cropping cycles are required to determine how soil carbon storage is significantly impacted by production systems.

Woodard, H. J.

2004-12-01

238

Modeling soil–root water transport and competition for single and mixed crops  

Microsoft Academic Search

A knowledge of above and below ground plant interactions for water is essential to understand the performance of intercropped systems. In this work, root water potential dynamics and water uptake partitioning were compared between single crops and intercrops, using a simulation model. Four root maps having 498, 364, 431 and 431 soil-root contacts were used. In the first and second

F. Lafolie; L. Bruckler; H. Ozier-Lafontaine; R. Tournebize; A. Mollier

1999-01-01

239

Vinasse Rate, Time of Application and Compaction Effect on Soil Properties and Durum Wheat Crop  

Microsoft Academic Search

The results of an experiment studying the effects of vinasse (an alcohol industry waste) recycling in agriculture are reported in this work. Vinasse was applied in a durum wheat crop by a trailed vinasse sprayer system compacting about 10% of the field. The experiment was carried out in Central Greece, on two soils (a clay and a silty clay loam)

T. A. Gemtos; N. Chouliaras

1999-01-01

240

What Does Undergraduate Enrollment in Soil and Crop Sciences Mean for the Future of Agronomy?  

Microsoft Academic Search

Soil and crop science programs at land-grant colleges have histori- cally relied on appropriated funding from state and federal sources and tuition to support the tripartite mission of research, extension, and teaching. However, due to declining funding from state and federal sources, tuition and fees are becoming increasingly important sources. As tuition revenue becomes more important, student enrollment be- comes

Neil Hansen; Sarah Ward; Raj Khosla; Jack Fenwick; Bill Moore

2007-01-01

241

No-Till Corn\\/Soybean Systems Including Winter Cover Crops: Effects on Soil Properties  

Microsoft Academic Search

The use of winter cover crops (WCC) such as hairy vetch (Vicia villosa Roth) and cereal rye (Secale cereale L.), in a corn (Zea mays L.)-soybean (Glycine max (L.) Merr.) rotation provides long-term benefits that are generally overlooked. There is a particular lack of information regarding the effects of WCC on soil physical and chemi- cal properties. The objective of

M. B. Villamil; G. A. Bollero; R. G. Darmody; F. W. Simmons; D. G. Bullock

242

State-space dynamic hydrological modeling of soil-crop-climate interactions  

NASA Astrophysics Data System (ADS)

The basic biological and hydrological processes of plant growth, such as CO2 assimilation, transpiration, growth, maintenance, and water uptake are discussed and quantified mathematically. A model is constructed in state-space form to simulate the seasonal growth of a crop under variable climatic forcing. The model takes into account the soil moisture and salinity profiles in a soil column. Salinity and moisture profiles are obtained by numerically solving the relevant mass transport equations. The morphology of the root system, which controls sink terms in the equation for transient unsaturated-saturated water transport, is explicitly determined by distributing the produced root biomass over depth so that the water uptake rate is maximized. The salinity concentration profile is used for predicting osmotic effects on the behavior of roots. A case study for maize is presented. It is shown that the crop response depends drastically on the climatic forcing, the soil salinity, and the irrigation practice. Necessary conditions for optimal growth are investigated. The temporal variation of many crop and soil variables is discussed. Finally, the ability of the model to produce the crop production function is demonstrated.

Protopapas, Angelos L.; Bras, Rafael L.

1988-10-01

243

Effect of cover crops management in aggregate stability of a vineyard in Central Spain  

Microsoft Academic Search

Our research focuses in cover crop treatments used to avoid soil degradation in hillsides. The soil-plant interaction can influence the soil structure. In this study we pay special attention to the soil aggregates in a hillside vineyard (average slope of 14%), under Mediterranean semiarid climatic conditions (average annual temperature 14°C, annual rainfall around 400 mm), in the South East of

Marta Ruiz-Colmenero; Ramon Bienes; Maria-Jose Marques

2010-01-01

244

Impact of topography and soil factors on crop suitability in two Mediterranean areas (Egypt and Spain)  

NASA Astrophysics Data System (ADS)

The aim of this research is to study the influence of topography and soil factors on crop suitability two Mediterranean areas: Sevilla (southern Spain) and El-Fayoum (northern Egypt). The Shuttle Radar Topography Mission (SRTM) images were processed using ENVI 4.7 software to extract elevation data, slope gradient and slope direction. North-south toposequences from both areas were extracted and studied using Arc-GIS 9.3 software. Soil characteristics along these toposequences were extracted from regional soil maps, as well as land surveying and laboratory analyses. The Almagra model (included in the agro-ecological system MicroLEIS DSS) was used to evaluate agricultural soil suitability using soil factors of useful depth, texture, drainage, carbonate content, salinity, sodium saturation, and degree of development of the profile. Changes of soil characteristics through the toposequences are discussed. The results of Almagra model indicate that the crop suitability main limiting factors are soil texture, drainage, soil salinity and sodium saturation percent and topography factors elevation, slope gradient, slope direction.

Abd-Elmabod, S. K.; Jordán, A.; Anaya-Romero, M.; Ali, R. R.; Muñoz-Rojas, M.; Zavala, L. M.; de la Rosa, D.

2012-04-01

245

Dryland Soil Greenhouse Gas Emissions Influenced by Tillage, Cropping Sequence, and Nitrogen Fertilization  

NASA Astrophysics Data System (ADS)

Management practices are needed to reduce greenhouse gas emissions from dryland agroecosystems. The effect of tillage, cropping sequence, and N fertilization on soil CO2, N2O, and CH4 fluxes was evaluated on a dryland loam soil from March to November, 2008 to 2010 in eastern Montana. Treatments were three cropping sequences [no-tilled continuous malt barley (NTCB), no-tilled malt barley-pea (NTB-P), and conventional-tilled malt barley-fallow (CTB-F)] and two N fertilization rates (0 and 80 kg N ha-1). The CO2 and N2O fluxes increased immediately following substantial precipitation during increased temperature in the summer from May to August. During this period, CO2 flux was greater in NTCB and NTB-P than in CTB-F and greater with 80 than with 0 kg N ha-1. The N2O flux varied with tillage and cropping sequence but was greater with 80 than with 0 kg N ha-1. Total CO2 flux from March to November was greater in NTCB than in CTB-F in all years and greater with 80 than with 0 kg N ha-1 in 2009 and 2010. Total N2O flux was not influenced by tillage, cropping sequence, and N fertilization. Both CO2 and N2O fluxes were greater in 2008 than in 2010. The CH4 flux remained negative at most measurement dates in all years. Increased root respiration and biomass production due to continuous cropping and N fertilization probably increased CO2 emissions under dryland cropping systems. Similarly, increased N availability probably increased N2O emissions during active crop growth. Increased soil water content due to greater rainfall probably increased CO2 and N2O emissions in 2008 than in 2010.

Sainju, U. M.; Biogeosciences

2011-12-01

246

SOIL PHYSICAL PROPERTIES AND CROP PRODUCTIVITY OF AN ERODED SOIL AMENDED WITH CATTLE MANURE  

Microsoft Academic Search

Erosion changes soil properties, especially physical properties, mainly because it removes surface soil rich in organic materials and exposes lower soil layers. In 1988, a study was established to determine the effects of soil erosion and long-term manure applications on selected soil phys­ ical properties and corn (Zea mays L.) production. After 10 years of an­ nual manure applications, soil

Francisco J. Arriaga; Birl Lowery

2003-01-01

247

Horizontal soil water potential heterogeneity: simplifying approaches for crop water dynamics models  

NASA Astrophysics Data System (ADS)

Soil water potential (SWP) is known to affect plant water status, and even though observations demonstrate that SWP distribution around roots may limit plant water availability, its horizontal heterogeneity within the root zone is often neglected in hydrological models. As motive, using a horizontal discretisation significantly larger than one centimetre is often essential for computing time considerations, especially for large-scale hydrodynamics models. In this paper, we simulate soil and root system hydrodynamics at the centimetre scale and evaluate approaches to upscale variables and parameters related to root water uptake (RWU) for two crop systems: a densely seeded crop with an average uniform distribution of roots in the horizontal direction (winter wheat) and a wide-row crop with lateral variations in root density (maize). In a first approach, the upscaled water potential at soil-root interfaces was assumed to equal the bulk SWP of the upscaled soil element. Using this assumption, the 3-D high-resolution model could be accurately upscaled to a 2-D model for maize and a 1-D model for wheat. The accuracy of the upscaled models generally increased with soil hydraulic conductivity, lateral homogeneity of root distribution, and low transpiration rate. The link between horizontal upscaling and an implicit assumption on soil water redistribution was demonstrated in quantitative terms, and explained upscaling accuracy. In a second approach, the soil-root interface water potential was estimated by using a constant rate analytical solution of the axisymmetric soil water flow towards individual roots. In addition to the theoretical model properties, effective properties were tested in order to account for unfulfilled assumptions of the analytical solution: non-uniform lateral root distributions and transient RWU rates. Significant improvements were however only noticed for winter wheat, for which the first approach was already satisfying. This study confirms that the use of 1-D spatial discretisation to represent soil-plant water dynamics is a worthy choice for densely seeded crops. For wide-row crops, e.g. maize, further theoretical developments that better account for horizontal SWP heterogeneity might be needed in order to properly predict soil-plant hydrodynamics in 1-D.

Couvreur, V.; Vanderborght, J.; Beff, L.; Javaux, M.

2014-05-01

248

Spatial distribution and controlling factors of heavy metals contents in paddy soil and crop grains of rice-wheat cropping system along highway in East China.  

PubMed

There is consensus concerning the heavy metal pollution from traffic emission on roadside agricultural land. However, few efforts have been paid on examining the contamination characteristics of heavy metals in roadside paddy-upland rotation field, and especially in combination with detailed quantitative analysis. In this study, we investigated the concentrations of heavy metals (Pb, Cd, Cr and Zn) in soil and crop grains of the rice-wheat cropping system along a major highway in East China in 2008 and analyzed the spatial distribution characteristics of heavy metals and their influencing factors with GIS and Classification and Regression Trees (CART). Significantly elevated levels of heavy metals in soil, rice and wheat grains indicated the heavy metals contamination of traffic emission in roadside rice-wheat rotation field. The contamination levels of Cd, Cr and Zn in wheat grain were higher than rice grain, while that of Pb showed an opposite trend. Obvious dissimilarities in the spatial distributions of heavy metals contents were found between in the soil, rice and wheat grains, indicating that the heavy metals contents in the roadside crop grains were not only determined by the concentrations of heavy metals in the paddy soil. Results of CART analysis showed that the spatial variation of the heavy metals contents in crop grains was mainly affected by the soil organic matter or soil pH, followed by the distance from highway and wind direction. Our findings have important implications for the environmental assessment and crop planning for food security along the highway. PMID:22527116

Feng, Jinfei; Zhao, Jian; Bian, Xinmin; Zhang, Weijian

2012-10-01

249

Interactions of soil conditioner with other limiting factors to achieve high crop yields. [Lycopersicon esculentum  

SciTech Connect

Tomato (Lycopersicon esculentum Mill. cv. Tropic) was used as a test plant in evaluating the interactions for simultaneously correcting deficiencies of N and P and improving physical properties of soil with a soil conditioner. The three limiting factors were improved singly and in all possible combinations. There was response to each input. The least response to the soil conditioner was with N and P, and the most response was when N and P were also used. The combined effect appeared to be synergistic. The results emphasize that the best crop management system involves overcoming as many limiting factors as possible. This is the key to high-yield agriculture.

Wallace, A.; Abouzamzam, A.M.

1986-05-01

250

The influence of cover crops and tillage on actual and potential soil erosion in an olive grove  

NASA Astrophysics Data System (ADS)

The study was carried out in an olive grove in central Spain (South of Madrid; Tagus River Basin). In this semi-arid zone, the annual mean temperature is 13.8 ºC and the annual precipitation is 395 mm. Olive groves are planted in an erosion prone area due to steep slopes up to 15%. Soil is classified as Typic Haploxerept with clay loam texture. The land studied was formerly a vineyard, but it was replaced by the studied olive grove in 2004. It covers approximately 3 ha and olive trees are planted every 6 x 7 metres. They were usually managed by tillage to decrease weed competition. This conventional practice results in a wide surface of bare soil prone to erosion processes. In the long term soil degradation may lead to increase the desertification risk in the area. Storms have important consequences in this shallow and vulnerable soil, as more than 90 Mg ha-1 have been measured after one day with 40 mm of rainfall. In order to avoid this situation, cover crops between the olive trees were planted three years ago: sainfoin (Onobrychis viciifolia), barley (Hordeum vulgare), and purple false brome (Brachypodium distachyon), and they were compared with annual spontaneous vegetation after a minimum tillage treatment (ASV). The results regarding erosion control were positive. We observed (Oct. 2012/Sept. 2013) annual soil loss up to 11 Mg ha-1 in ASV, but this figure was reduced in the sown covers, being 8 Mg ha-1 in sainfoin treatment, 3,7 Mg ha-1 in barley treatment, and only 1,5 Mg ha-1 in false brome treatment. Those results are used to predict the risk of erosion in long term. Moreover, soil organic carbon (SOC) increased with treatments, this is significant as it reduces soil erodibility. The increases were found both in topsoil (up to 5 cm) and more in depth, in the root zone (from 5 to 10 cm depth). From higher to lower SOC values we found the false brome (1.05%), barley (0.92%), ASV (0.79%) and sainfoin (0.71%) regarding topsoil. In the root zone (5-10 cm depth) we found 0.76% in false brome and ASV, 0.70% in barley and 0.58% in sainfoin. Other important variable to estimate erosion processes is soil permeability. During the period of study there were no significant differences between treatments. An average of 45±20 mm h-1 was measured. This study addresses the comparison between soil erosion rates measured on the ground with soil erosion risk estimated by models. Mapping soil risk can provide the evidence to demonstrate that economic investments in research, good practices and agri-environment payments are worth to achieve sustainable land management. The use of case studies is usually recommended to help in the dissemination of research. This case also includes the influence of treatments in production and quality of olive oil to respond to the needs of land users.

Sastre, Blanca; Bienes, Ramón; García-Díaz, Andrés; Panagopoulos, Thomas; José Marqués, Maria

2014-05-01

251

Impact of different bioenergy crops on N-cycling bacterial and archaeal communities in soil.  

PubMed

Biomass production for bioenergy may change soil microbes and influence ecosystem properties. To explore the impact of different bioenergy cropping systems on soil microorganisms, the compositions and quantities of soil microbial communities (16S rRNA gene) and N-cycling functional groups (nifH, bacterial amoA, archaeal amoA and nosZ genes) were assessed under maize, switchgrass and Miscanthus x giganteus at seven sites representing a climate gradient (precipitation and temperature) in Illinois, USA. Overall, the site-to-site variation in community composition surpassed the variation due to plant type, and microbial communities under each crop did not converge on a 'typical' species assemblage. Fewer than 5% of archaeal amoA, bacterial amoA, nifH and nosZ OTUs were significantly different among these crops, but the largest differences observed at each site were found between maize and the two perennial grasses. Quantitative PCR revealed that the abundance of the nifH gene was significantly higher in the perennial grasses than in maize, and we also found significantly higher total N in the perennial grass soils than in maize. Thus, we conclude that cultivation of these perennial grasses, instead of maize, as bioenergy feedstocks can improve soil ecosystem nitrogen sustainability by increasing the population size of N-fixing bacteria. PMID:22891790

Mao, Yuejian; Yannarell, Anthony C; Davis, Sarah C; Mackie, Roderick I

2013-03-01

252

Implementation of Sustainable Soil Management Practices to Improve Crop Production in the Different Ethiopian Agro Systems  

NASA Astrophysics Data System (ADS)

Agriculture in Ethiopia is one of first priority since close to 10 In this context, the Ethiopian crop production faces to the following soil management challenges: lack of updated soil data, macro and micro nutrient depletion, acidity, salinity and soil surface erosion and crusting. One of the biggest issues is the loss of arable land, above 137 T/yr, reaching during some particularly dried periods until 300 T/yr. In this context, the authors constituted a working group of experts from Spanish and Ethiopian universities, local producers and international and governmental organisms to analyse the problems related to the different agro ecological zones found in Ethiopia and the management practices of different local producers. The study produced the trends to implement in the different areas to improve soil management practices in order to contribute to increase the crop production mainly to achieve food security problems. The analyse produced different working fields for the next years for addressing soil degradation, improving land resources management practices, increasing agricultural productivity, updating the available soil data, developing an international program of education, transferring of knowledge from similar study cases and implementing economical tools to help producers to assure income after severe edapho-climatic events. The practical work and the projects developed for the next period is addressed to smallholder farms belonging to the different 34 agro ecological zones identified in Ethiopia, each of them with very specific environmental, cultural and soil management practices.

García Moreno, R.; Gameda, S.; Diaz Alvarez, M. C.; Selasie, Y. G.

2012-04-01

253

Removal of arsenic from Janghang smelter site and energy crops-grown soil with soil washing using magnetic iron oxide  

NASA Astrophysics Data System (ADS)

Arsenic compounds are considered carcinogen and easily enter drinking water supplies with their natural abundance. US Environmental Protection Agency is finalizing a regulation to reduce the public health risks from arsenic in drinking water by revising the current drinking water standard for arsenic from 50 ppb to 10 ppb in 2001 (USEPA, 2001). Therefore, soil remediation is also growing field to prevent contamination of groundwater as well as crop cultivation. Soil washing is adjusted as ex-situ soil remediation technique which reduces volume of the contaminated soil. The technique is composed of physical separation and chemical extraction to extract target metal contamination in the soil. Chemical extraction methods have been developed solubilizing contaminants containing reagents such as acids or chelating agents. And acid extraction is proven as the most commonly used technology to treat heavy metals in soil, sediment, and sludge (FRTR, 2007). Due to the unique physical and chemical properties, magnetic iron oxide have been used in diverse areas including information technology and biomedicine. Magnetic iron oxides also can be used as adsorbent to heavy metal enhancing removal efficiency of arsenic concentration. In this study, magnetite is used as the washing agent with acid extraction condition so that the injected oxide can be separated by magnetic field. Soil samples were collected from three separate areas in the Janghang smelter site and energy crops-grown soil to have synergy effect with phytoremediation. Each sample was air-dried and sieved (2mm). Soil washing condition was adjusted on pH in the range of 0-12 with hydrogen chloride and sodium hydroxide. After performing soil washing procedure, arsenic-extracted samples were analyzed for arsenic concentration by inductively coupled plasma optical emission spectrometer (ICP-OES). All the soils have exceeded worrisome level of soil contamination for region 1 (25mg/kg) so the soil remediation techniques are needed to be applied. The objective of this study is to investigate soil washing efficiency using magnetic iron oxide and derive the availability of the washing technique to the arsenic-contaminated field soils. Acknowledgement This study was supported by Korea Ministry of Environment as 'Knowledge-based environmental service (Waste to Energy) Human Resource Development Project'.

Han, Jaemaro; Zhao, Xin; Lee, Jong Keun; Kim, Jae Young

2014-05-01

254

Illinois biomass resources: annual crops and residues; canning and food-processing wastes. Preliminary assessment  

SciTech Connect

Illinois, a major agricultural and food-processing state, produces vast amounts of renewable plant material having potential for energy production. This biomass, in the form of annual crops, crop residues, and food-processing wastes, can be converted to alternative fuels (such as ethanol) and industrial chemicals (such as furfural, ethylene, and xylene). The present study provides a preliminary assessment of these Illinois biomass resources, including (a) an appraisal of the effects of their use on both agriculture and industry; (b) an analysis of biomass conversion systems; and (c) an environmental and economic evaluation of products that could be generated from biomass. It is estimated that, of the 39 x 10/sup 6/ tons of residues generated in 1978 in Illinois from seven main crops, about 85% was collectible. The thermal energy equivalent of this material is 658 x 10/sup 6/ Btu, or 0.66 quad. And by fermenting 10% of the corn grain grown in Illinois, some 323 million gallons of ethanol could have been produced in 1978. Another 3 million gallons of ethanol could have been produced in the same year from wastes generated by the state's food-processing establishments. Clearly, Illinois can strengthen its economy substantially by the development of industries that produce biomass-derived fuels and chemicals. In addition, a thorough evaluation should be made of the potential for using the state's less-exploitable land for the growing of additional biomass.

Antonopoulos, A A

1980-06-01

255

Soil, Water, and Greenhouse-gas Impacts of Alternative Biomass Cropping Systems  

NASA Astrophysics Data System (ADS)

Through the 2008 Energy Independence and Security Act and other state and federal mandates, the U.S. is embarking on an aggressive agenda to reduce dependency on fossil fuels. While grain-derived ethanol will be used to largely meet initial renewable fuels targets, advanced biofuels derived from lignocellulosic materials are expected to comprise a growing proportion of the renewable energy portfolio and provide a more sustainable solution. As part of our interdisciplinary research, we are assessing the environmental impacts of four lignocellulosic biomass cropping systems and comparing them to a conventional corn cropping system. This comparison is conducted using a randomized, replicated experiment initiated in fall 2008, which compares the five cropping systems across a toposequence (i.e., floodplain, toeslope, backslope, shoulder, summit). In addition to assessing herbaceous and woody biomass yields, we are evaluating the environmental performance of these systems through changes in water quality, greenhouse-gas emissions, and carbon pools. Initial results document baseline soil parameters, including the capacity of the soils to sequester carbon across the toposequence, and the impacts of landscape heterogeneity and cropping system on soil moisture and nitrate-nitrogen levels in the vadose zone. Additional results on greenhouse-gas emissions and carbon dynamics are forthcoming from this year’s field research. The fuller understanding of the environmental performance of these systems will help inform federal and state policies seeking to incentivize the development of a sustainable bioenergy industry.

Schulte Moore, L. A.; Bach, E.; Cambardella, C.; Hargreaves, S.; Helmers, M.; Hofmockel, K.; Isenhart, T.; Kolka, R. K.; Ontl, T.; Welsh, W.; Williams, R.; Landscape Biomass Team

2010-12-01

256

The potential of agricultural practices to increase C storage in cropped soils: an assessment for France  

NASA Astrophysics Data System (ADS)

Though large progress has been achieved in the last decades, net GHG emissions from the agricultural sector are still more poorly quantified than in other sectors. In this study, we examined i) technical mitigation options likely to store carbon in agricultural soils, ii) their potential of additional C storage per unit surface area and iii) applicable areas in mainland France. We considered only agricultural practices being technically feasible by farmers and involving no major change in either production systems or production levels. Moreover, only currently available techniques with validated efficiencies and presenting no major negative environmental impacts were taken into account. Four measures were expected to store additional C in agricultural soils: - Reducing tillage: either a switch to continuous direct seeding, direct seeding with occasional tillage once every five years, or continuous superficial (<15 cm) tillage. - Introducing cover crops in cropping systems: sown between two cash crops on arable farms, in orchards and vineyards (permanent or temporary cover cropping) . - Expanding agroforestry systems; planting of tree lines in cultivated fields and grasslands, and hedges around the field edges. - Increasing the life time of temporary sown grasslands: increase of life time to 5 years. The recent literature was reviewed in order to determine long term (>20yrs) C storage rates (MgC ha-1 y-1,) of cropping systems with and without the proposed practice. Then we analysed the conditions for potential application, in terms of feasibility, acceptance, limitation of yield losses and of other GHG emissions. According to the literature, additional C storage rates were 0.15 (0-0.3) MgC ha-1 y-1 for continuous direct seeding, 0.10 (0-0.2) MgC ha-1 y-1for occasional tillage one year in five, and 0.0 MgC ha-1 y-1 for superficial tillage. Cover crops were estimated to store 0.24 (0.13-0.37) MgC ha-1 y-1 between cash crops and 0.49 (0.23-0.72) MgC ha-1 y-1 when associated with vineyards. Hedges (i.e 60 m ha-1) stored 0.15 (0.05-0.26) Mg C ha-1 y-1. Very few estimates were available for temperate agroforestry system, and we proposed a value of 1.01 (0.11-1.36) Mg C ha-1 y-1for C stored in soil and in the tree biomass for systems comprising 30-50 trees ha-1. Increasing the life time of temporary sown grassland increased C stocls by 0.11 (0.07-0.22) Mg C ha-1 y-1. In general, practices with increased C inputs to soil through additional plant biomass (agroforestry, hedges and cover crops) resulted in higher additional C storage rates, while the reduction of soil organic matter mineralisation through reduced tillage seemed less effective. When applied to the French agricultural sector, excluding areas with soils with major technical constraints or negative environmental consequences (e.g. poorly aerated soils with high N2O emissions), the measures considered here allowed to increase French soil C stocks by 0 to more than 1 Tg C y-1. However, our estimates are associated with high uncertainties, due to the high variability in soil C storage associated with pedo-climatic conditions and cropping systems, and on the very few studies available for some practices such as agroforestry under temperate conditions.

Chenu, Claire; Angers, Denis; Métay, Aurélie; Colnenne, Caroline; Klumpp, Katja; Bamière, Laure; Pardon, Lenaic; Pellerin, Sylvain

2014-05-01

257

Assessing Effects of Transgenic Crops on Soil Microbial Communities  

Microsoft Academic Search

Deleterious effects of transgenic plants on soils represent an often expressed concern, which has\\u000a catalyzed numerous studies in the recent past. In this literature review, studies addressing this question\\u000a have been compiled. A total of 60 studies has been found, and their findings as well as their analytical\\u000a approaches are summarized. These studies analyzed the effects of seven different types of

Franco Widmer

258

Evaluating energy sorghum harvest thresholds and tillage cropping systems to offset negative environmental impacts and harvesting equipment-induced soil compaction  

NASA Astrophysics Data System (ADS)

Energy sorghum (Sorghum bicolor L. Moench) could be the ideal feedstock for the cellulosic ethanol industry because of its robust establishment, broader adaptability and drought tolerance, water and nutrient use efficiency, and the relatively high annual biomass yields. Of concern, however, is the limited research data on harvest thresholds, subsequent environmental impacts and the potential cumulative effects of harvesting equipment-induced soil compaction. Indiscriminate harvests of the high volume wet energy sorghum biomass, coupled with repeated field passes, could cause irreparable damage to the soil due to compaction. Furthermore, biomass harvests result in lower soil organic matter returns to the soil, making the soil even more susceptible to soil compaction. Compacted soils result in poor root zone aeration and drainage, more losses of nitrogen from denitrification, and restricted root growth, which reduces yields. Given the many positive attributes of conservation tillage and crop residue retention, our research and extension expectations are that sustainable energy sorghum cropping systems ought to include some form of conservation tillage. The challenge is to select cropping and harvesting systems that optimize feedstock production while ensuring adequate residue biomass to sustainably maintain soil structure and productivity. Producers may have to periodically subsoil-till or plow-back their lands to alleviate problems of soil compaction and drainage, weeds, insects and disease infestations. Little, however, is known about the potential impact of these tillage changes on soil productivity, environmental integrity, and sustainability of bioenergy agro-ecosystems. Furthermore, 'safe' energy sorghum feedstock removal thresholds have yet to be established. We will apply the ALMANAC biophysical model to evaluate permissible energy sorghum feedstock harvest thresholds and the effects of subsoil tillage and periodically plowing no-tilled (NT) energy sorghum fields. The presentation will provide long-term insights into the sustainability of the proposed interventions with regards to 'safe' harvest thresholds, feedstock yields, SOC storage and rate of change, and sediment and nutrient (N&P) losses. Model calibration and validation datasets have already been compiled from rainfed and irrigated energy sorghum field studies conducted in Arkansas and Alabama during the years: 2008 to 2010. We compiled energy sorghum crop parameters based on data extracted from the literature, expert judgment and field experiments. Simulations will be made for combinations of biomass harvest rates, tillage systems, weather, soil type, and dryland production over a 51-year time series (1960-2010).

Meki, M. N.; Snider, J. L.; Kiniry, J. R.; Raper, R. L.; Rocateli, A. C.

2011-12-01

259

Gap filling strategies and error in estimating annual soil respiration.  

PubMed

Soil respiration (Rsoil ) is one of the largest CO2 fluxes in the global carbon (C) cycle. Estimation of annual Rsoil requires extrapolation of survey measurements or gap filling of automated records to produce a complete time series. Although many gap filling methodologies have been employed, there is no standardized procedure for producing defensible estimates of annual Rsoil . Here, we test the reliability of nine different gap filling techniques by inserting artificial gaps into 20 automated Rsoil records and comparing gap filling Rsoil estimates of each technique to measured values. We show that although the most commonly used techniques do not, on average, produce large systematic biases, gap filling accuracy may be significantly improved through application of the most reliable methods. All methods performed best at lower gap fractions and had relatively high, systematic errors for simulated survey measurements. Overall, the most accurate technique estimated Rsoil based on the soil temperature dependence of Rsoil by assuming constant temperature sensitivity and linearly interpolating reference respiration (Rsoil at 10 °C) across gaps. The linear interpolation method was the second best-performing method. In contrast, estimating Rsoil based on a single annual Rsoil - Tsoil relationship, which is currently the most commonly used technique, was among the most poorly-performing methods. Thus, our analysis demonstrates that gap filling accuracy may be improved substantially without sacrificing computational simplicity. Improved and standardized techniques for estimation of annual Rsoil will be valuable for understanding the role of Rsoil in the global C cycle. PMID:23504959

Gomez-Casanovas, Nuria; Anderson-Teixeira, Kristina; Zeri, Marcelo; Bernacchi, Carl J; DeLucia, Evan H

2013-06-01

260

Determine metrics and set targets for soil quality on agriculture residue and energy crop pathways  

SciTech Connect

There are three objectives for this project: 1) support OBP in meeting MYPP stated performance goals for the Sustainability Platform, 2) develop integrated feedstock production system designs that increase total productivity of the land, decrease delivered feedstock cost to the conversion facilities, and increase environmental performance of the production system, and 3) deliver to the bioenergy community robust datasets and flexible analysis tools for establishing sustainable and viable use of agricultural residues and dedicated energy crops. The key project outcome to date has been the development and deployment of a sustainable agricultural residue removal decision support framework. The modeling framework has been used to produce a revised national assessment of sustainable residue removal potential. The national assessment datasets are being used to update national resource assessment supply curves using POLYSIS. The residue removal modeling framework has also been enhanced to support high fidelity sub-field scale sustainable removal analyses. The framework has been deployed through a web application and a mobile application. The mobile application is being used extensively in the field with industry, research, and USDA NRCS partners to support and validate sustainable residue removal decisions. The results detailed in this report have set targets for increasing soil sustainability by focusing on primary soil quality indicators (total organic carbon and erosion) in two agricultural residue management pathways and a dedicated energy crop pathway. The two residue pathway targets were set to, 1) increase residue removal by 50% while maintaining soil quality, and 2) increase soil quality by 5% as measured by Soil Management Assessment Framework indicators. The energy crop pathway was set to increase soil quality by 10% using these same indicators. To demonstrate the feasibility and impact of each of these targets, seven case studies spanning the US are presented. The analysis has shown that the feedstock production systems are capable of simultaneously increasing productivity and soil sustainability.

Ian Bonner; David Muth

2013-09-01

261

Transfer factors of radioiodine from volcanic-ash soil (Andosol) to crops.  

PubMed

In order to obtain soil-to-plant transfer factors (TFs) of radioiodine from volcanic-ash soil to agricultural crops, we carried out radiotracer experiments. The mean values of TFs (on a wet weight basis) of radioiodine from Andosol to edible parts of crops were as follows: water dropwort, 0.24; lettuce, 0.00098; onion, 0.0011; radish, 0.0044; turnip, 0.0013 and eggplant, 0.00010. The mean value of the TFs of radioiodine for edible parts of wheat (on a dry weight basis) was 0.00015. We also studied the distributions of iodine in crops. There was a tendency for the TFs of leaves to be higher than those of tubers, fruits and grains. A very high TF was found for water dropwort, because this plant was cultivated under a waterlogged condition, in which iodine desorbed from soil into soil solution with a drop in the Eh value. The data obtained in this study should be helpful to assess the long-lived 129I (half life: 1.57 x 10(7) yr) pathway related to the fuel cycle. PMID:12841595

Ban-Nai, Tadaaki; Muramatsu, Yasuyuki

2003-03-01

262

Black oat cover crop management effects on soil temperature and biological properties on a Mollisol in Texas, USA  

Microsoft Academic Search

Management of a black oat (Avena strigosa [Schreb.]) cover crop by mowing method (none, flail mowing, or sickle bar mowing) affected soil micro environmental conditions and soil microbial and chemical properties. Soil temperatures at depths of 0, 5, 10 and 20 cm were highest in flail mowed treatment plots (up to near 45 °C at 5 cm depth), followed by sickle bar mowed

L. M. Zibilske; D. J. Makus

2009-01-01

263

Soil microbial activities in tree-based cropping systems and natural forests of the Central Amazon, Brazil  

Microsoft Academic Search

Little information is available about the factors controlling soil C and N transformations in natural tropical forests and tree-based cropping systems. The aim of this work was to study the effects of single trees on soil microbiological activities from plantations of timber and non-timber species as well as species of primary and secondary forests in the Central Amazon. Soil samples

Oleg V. Menyailo; Johannes Lehmann; Manoel da Silva Cravo; Wolfgang Zech

2003-01-01

264

Irrigation with treated wastewater: effects on soil, lettuce (Lactuca sativa L.) crop and dynamics of microorganisms.  

PubMed

The aim of this study was to evaluate the applicability of treated wastewater for horticultural crops, assess the effects of continuous use of treated water on soil and crops, and analyse the physical, chemical and biological effects of irrigation with recycled water. Two lettuce plots watered with drinking water and treated wastewater were monitored over a three year period. Nutrients, heavy metal and the dynamics of pathogen and indicator microorganism content in soil and foliar tissues were analysed. Wastewater irrigation had a high influence on soil parameters: organic matter, N, P, Ca, Al, Fe, Pb and Zn. Indicator and pathogenic microorganisms were detected in soil and plants grown in the wastewater-irrigated plot, and persisted in the soil for 27 days during the study under humid conditions. N, P, Pb and Al content were significantly higher in plant tissues of wastewater-irrigated plots than in the control after 3 years of irrigation. Harvest was significantly higher in the wastewater-irrigated plot. Wastewater can be a resource for agricultural irrigation. In any case, the possible heavy metal accumulation in soils and presence of pathogenic organisms require careful management of this alternative resource: use of a drip irrigation system, previous wastewater disinfection and a limited irrigation period are recommended. PMID:19847714

Mañas, Pilar; Castro, Elena; de Las Heras, Jorge

2009-10-01

265

Soil survey versus crop production as a measure of soil productivity: Soil characteristics as predictors of corn and soybean yields, NCSS (National Cooperative Soil Survey) data base. Final report  

SciTech Connect

Information has been assembled concerning land as a resource for farming and other endeavors. Major land resources areas (MLRAs) consist of geographically associated land resource units characterized by particular patterns of soil, climate, use and type of farming. The National Cooperative Soil Survey data base contains information concerned with crop yield and soil characteristics associated with MLRAs. Within MLRAs are various soils that have different chemical and physical properties such as soil pH, percent organic matter and texture, and that have different characteristics such as erosion and slope. A major objective of the project was to establish and evaluate a general, quantitative relationship between soil characteristics and yields for MLRAs in Iowa and Illinois. Statistical model building procedures were the methodology used in the evaluation and the test crops were corn and soybeans since these crops are widely produced in both states and on most soils.

Jansen, I.J.; Vance, S.L.; Walker, W.M.

1985-12-30

266

Influence of field histories of continuous soil insecticide treatments on the rate of soil biodegradation of Carbofuran in cauliflower, Brussels sprouts, Chinese cabbage and sugar beet crops  

Microsoft Academic Search

In the soil of cauliflower, Brussels sprouts, Chinese cabbage and sugar beet crops, carbofuran was metabolized into the insecticide compounds 3?hydroxycarbofuran and 3?ketocarbofuran, and into the non insecticide carbofuran phenol and 3?ketocarbofuran phenol. The rate of soil biodegradation of carbofuran and of the sum of insecticide carbamate compounds was multiplied by 3 when continuous monoculture and soil treatments with organophosphorus

Jean Rouchaud; Marc Metsue; Frans van de Steene; Christian Pelerents; Frans Benoit; Norbert Ceustermans; Luc Vanparys; Joël Gillet; Edgard Seutin

1989-01-01

267

Effect of cover crops and tillage system on symphylan (Symphlya: Scutigerella immaculata, Newport) and Pergamasus quisquiliarum Canestrini (Acari: Mesostigmata) populations, and other soil organisms in agricultural soils  

Microsoft Academic Search

The garden symphylan (Scutigerella immaculata: Newport) is a common myriapod soil pest of vegetable crops in the Pacific Northwest and other regions of the US. Symphylans consume germinating seeds, plant roots, and above-ground plant parts in contact with the soil. Factors regulating symphylan populations in agricultural soil systems are poorly understood, particularly the effects of farming practices such as cover

R. E Peachey; A Moldenke; R. D William; R Berry; E Ingham; Eric Groth

2002-01-01

268

Season and soil management affect soil microbial communities estimated using phospholipid fatty acid analysis in a continuous cabbage (Brassica oleracea var. capitata) cropping system  

Microsoft Academic Search

The effects of soil management on seasonal changes in soil microbial communities were examined in a continuously cropped field of cabbage (Brassica oleracea var. capitata) using phospholipid fatty acid (PLFA) analysis. Soil samples from each plot treated with cattle manure compost (CMC), grass compost (GRC) and chemical fertilizers (CHF) were taken at monthly intervals from April 2003 to March 2004.

Hiroyasu Tabuchi; Kotaro Kato; Ichio Nioh

2008-01-01

269

Scenarios of organic amendment use to increase soil carbon stocks and nitrogen availability in cropped soils at the territory scale: spatial and temporal simulations with the NCSOIL/CERES-EGC crop model  

NASA Astrophysics Data System (ADS)

The application of Exogenous Organic Matter (EOM) on cropped soils is a promising way to increase soil organic carbon and available nitrogen for crops while recycling organic agricultural and urban wastes. In peri-urban territories where the specialization of agriculture limits the resource in organic amendments since livestock farming is scarce, a better management of EOM land application from all origins at the territory scale could be thought to maximize their benefits. The objective was to predict the effect of various EOM types and uses on C and N fluxes and crop production for each homogeneous spatial unit of the territory, first step for the territorial optimization of EOM land application. The study area, located 30km west of Paris, covers 221km² and is mostly characterized by croplands. The effects of repeated EOM applications were studied using a mechanistic crop model: CERES-EGC accounting for soil characteristics, crop production systems, and climate. The whole territory was divided into homogeneous spatial units, each defined by soil and crop production system characteristics. Four different soil types were characterized, mapped and parameterized in the model. Kinetics of C and N mineralization during soil incubations were used to optimize soil organic matter characteristics and parameters in the sub-model NCSOIL of CERES-EGC. Crop production systems were defined and spatially inferred using the French land parcel identification system. Climatic data measured on the territory were used to make a 20 year-meteorological scenario. Based on these initial informations, crop yields and C and N fluxes were simulated for the actual crop productions and soil type combinations of the territory. Then, different scenarios of EOM uses were also simulated based on different EOM types, added quantities and frequencies of application within the crop successions respecting the 170kgN/ha/yr legal limit. All the parameters studied, crop yields, N outputs, carbon storage increased with increasing amounts of applied EOM but to different extents depending on added EOM, soil type and crop production system. Based on all the simulated results obtained, the EOM land application will be optimized to maximize carbon storage, crop production and limit N pollutions at the territory scale, taking into account other constraints such as EOM availability.

Noirot-Cosson, Paul-Emile; Vaudour, Emmanuelle; Aubry, Christine; Gilliot, Jean-Marc; Gabrielle, Benoît; Houot, Sabine

2014-05-01

270

Assessment of the Impacts of Rice Cropping through a Soil Quality Index  

NASA Astrophysics Data System (ADS)

In Entre Ríos (Argentina), rice cultivation is carried out mainly in Vertisols. Several factors, such as the use of sodium bicarbonate waters for irrigation, the excessive tillage required, and the lack of proper planning for land use, mainly regarding the crop sequence, cause serious impacts on the soil and have an effect on sustainable agriculture. Thus, the development of methodologies to detect these impacts has become a priority. The aim of this study was to standardize soil quality indicators (SQI) and integrate them into an index to evaluate the impacts of the rice production system on soil, at the farm scale. The study was conducted in farms of the traditional rice cultivation area of Entre Ríos province, Argentina. We evaluated a minimum data set consisting of six indicators: structural stability and percolation, total organic matter content (TOM), exchangeable sodium content (ESC), electrical conductivity of saturation extract (ECe) and reaction of the soil (pH). From a database from 75 production lots, we determined the reference values, i.e. limits to ensure the maintenance of long-term productivity and the allowable thresholds for each indicator. The indicators were standardized and integrated into a soil quality index. Five ranges of soil quality were established: very low, low, moderate, high and very high, depending on the values assigned to each SQI. This index allowed differentiating the impact of different crop sequences and showed that the increased participation of rice crop in the rotation resulted in a deterioration of the soil structure due to the decrease in the TOM and to the cumulative increase in ESC caused by the sodium bicarbonate water used for irrigation. Soil management strategies should aim to increase TOM values and to reduce the input of sodium to the exchange complex. A rotation with 50% to 60% of pasture and 40 to 50% of agriculture with a participation of rice lower than 20 to 25% would allow the sustainability of the production system. The use of the so called SQI, i.e. soil quality index, for rice crop production will allow generating early warning of degradation and thus adopting recovery measures.

Sione, S. M.; Wilson, M. G.; Paz González, A.

2012-04-01

271

The drought of 2012: Effects on photosynthesis and soil respiration in bioenergy cropping systems of the Midwest USA  

NASA Astrophysics Data System (ADS)

Climate change is predicted to increase the frequency and severity of drought conditions across the central US. This heightened risk on producers and economies alike also supports the need to improve our understanding of how extreme environmental conditions impact other ecosystem services such as carbon sequestration, which is directly linked to net ecosystem exchange (NEE). In doing so, the scientific community aims to improve the realism of ecosystem models that are relied upon to project changes in large scale and long-term land surface-atmosphere carbon exchange as they are affected by continued land management change and climate change. One such large-scale land management change of the next several decades in the Midwest US could be the expansion of bioenergy cropping systems across the landscape. A wide range of bioenergy cropping systems (e.g., miscanthus, switchgrass, diverse prairie, hybrid poplar) are now targeted to support a feedstock supply chain for production of cellulosic biofuels. Many of these agroecosystems have only recently begun to appear as functional types in dynamic ecosystem models, and a general lack of observational data across a wide range of soils and climate has hampered model development and validation. In response to this shortcoming, from 2009 through 2012, component measurements of ecosystem carbon exchange (total soil respiration and leaf level photosynthetic rates) have been made along with measurements of other soil and meteorological variables in three model bioenergy cropping systems (continuous corn, hybrid poplar and switchgrass) at the Great Lakes Bioenergy Research Center (GLBRC) field trial at Arlington, Wisconsin. The three cropping systems encompass a wide range of growth (e.g. C3 vs. C4, annual vs. perennial) and management (e.g., tillage, harvesting) strategies that are predicted to impart different controls on NEE given likely varying biological responses to extreme weather events. Throughout the study period, the field site has been exposed to extreme variations in precipitation and temperature, from what might be considered an ideal/wet year in 2010 to a catastrophic drought in 2012. Measurements of soil temperature during the growing season of 2012 show an increase of 1.7°C to 4.6°C when compared to 2010 and concurrent measurements of volumetric water content decreased from 0.34 in 2010 to 0.05 in 2012. We compare and contrast component measurements of NEE (i.e. soil respiration and leaf level photosynthesis), using chamber-based methods in the field, and their responses to environmental conditions. Some preliminary results show that soil respiration measurements during summer 2012 exhibited a 20% increase to a 43% decrease compared to similar measurements taken in 2010. During the middle of the growing season, the maximum rate of photosynthesis was reduced in 2012 in comparison to 2010 by 36%, 53% and 66% for corn, switchgrass and hybrid poplar, respectively, for light saturated leaves with a temperature near 30°C. These data will aid in the development of better numerical functions in ecosystem models that aim to represent the influence of temperature and soil water potential on the exchange of CO2 between the land surface and the atmosphere in agroecosystems.

Cruse, M.; Kucharik, C. J.

2012-12-01

272

Gopher mound soil reduces growth and affects ion uptake of two annual grassland species  

Microsoft Academic Search

Portions of an annual serpentine grassland community in California are subject to frequent gopher mound formation. Consequently, studies were undertaken to characterize the effects of mound soils on plant growth and ion uptake. For two of the dominant annual species (Bromus mollis L. and Plantago erecta Morris), growth was reduced in gopher mound soil relative to that in inter-mound soil.

R. T. Koide; L. F. Huenneke; H. A. Mooney

1987-01-01

273

Interacting Effects of Heat Stress and Soil Moisture Stress on Crop Yield Losses in Dryland Agriculture  

NASA Astrophysics Data System (ADS)

Increased interannual variability and greater frequency of extreme events place new pressures on subsistence farmers as a direct result of climate change. Of particular concern are farmers practicing rainfed agriculture in dryland ecosytems, where food security is closely linked to climate. In these areas, an improved understanding of the occurrence of extreme events as well as their effects on crop yields is essential. The main goals of this research are to identify the relative importance and possible coupling of heat stress and soil moisture stress in determining dryland crop yield losses. In particular, we are interested in determining the extent to which irrigation is an effective buffer against drought and heat stress in dryland regions. While irrigation can protect against soil moisture stress, its ability to mitigate heat stress, or the combined effects of the two stresses, is uncertain. Our study focuses on the Eastern and Southern provinces of Zambia as characteristic regions of dryland agriculture. Sites in the study area are identified based on farming type (irrigated versus rainfed). As irrigation is assumed to negate soil moisture stress, this approach enables separate analysis of heat stress and soil moisture stress, as well as their combined effects. To quantify the effects of heat stress, distributions of daily minimum and maximum temperatures are used to identify the frequency and severity of anomalously warm periods and their correlation with resulting crop yield losses. We also utilize Standardized Precipitation Index (SPI) data and soil moisture data derived from the Variable Infiltration Capacity (VIC) macroscale hydrologic model to examine the effects of meteorological drought and hydrological drought, respectively, on crop yields. To quantify crop yield losses, we employ yield estimates derived from the integration of time series of 250 meter resolution Normalized Difference Vegetation Index (NDVI) images collected by the Moderate Resolution Imaging Spectrometer (MODIS) for 11 consecutive growing seasons, beginning in the 2000-2001 season and ending in 2011-2012. The NDVI data also allows us to study the sensitivity of crops to extreme events during particular stages of their lifecycle, as well as triggers for early senescence.

Debats, S. R.; Caylor, K. K.; Estes, L. D.; Chaney, N.; Sheffield, J.

2012-12-01

274

Procedures for the description of agricultural crops and soils in optical and microwave remote sensing studies  

NASA Technical Reports Server (NTRS)

This paper describes procedures for characterizing agricultural crops and soils in remote sensing studies. The procedures are based on the accumulated experience of a number of researchers active in this field. Therefore, they represent a compromise between the theoretically desirable and the practically feasible, and should thus be an effective aid in further studies of this type. Although the guidelines were prepared specifically for microwave studies, adjustments were made to render the procedures applicable to optical studies as well. Given the increasing number of research teams involved in remote sensing applied to agriculture, there is an opportunity to acquire a broad data base on soils and crops in various geographic regions. To allow intercomparisons of such data, they must be obtained in a consistent manner. By following the proposed procedures and reporting results using the parameters described here, such intercomparisons should be possible on a continental or a global scale.

Cihlar, J.; Dobson, M. C.; Schmugge, T.; Hoogeboom, P.; Janse, A. R. P.

1987-01-01

275

The Effects of Manure and Nitrogen Fertilizer Applications on Soil Organic Carbon and Nitrogen in a High-Input Cropping System  

PubMed Central

With the goal of improving N fertilizer management to maximize soil organic carbon (SOC) storage and minimize N losses in high-intensity cropping system, a 6-years greenhouse vegetable experiment was conducted from 2004 to 2010 in Shouguang, northern China. Treatment tested the effects of organic manure and N fertilizer on SOC, total N (TN) pool and annual apparent N losses. The results demonstrated that SOC and TN concentrations in the 0-10cm soil layer decreased significantly without organic manure and mineral N applications, primarily because of the decomposition of stable C. Increasing C inputs through wheat straw and chicken manure incorporation couldn't increase SOC pools over the 4 year duration of the experiment. In contrast to the organic manure treatment, the SOC and TN pools were not increased with the combination of organic manure and N fertilizer. However, the soil labile carbon fractions increased significantly when both chicken manure and N fertilizer were applied together. Additionally, lower optimized N fertilizer inputs did not decrease SOC and TN accumulation compared with conventional N applications. Despite the annual apparent N losses for the optimized N treatment were significantly lower than that for the conventional N treatment, the unchanged SOC over the past 6 years might limit N storage in the soil and more surplus N were lost to the environment. Consequently, optimized N fertilizer inputs according to root-zone N management did not influence the accumulation of SOC and TN in soil; but beneficial in reducing apparent N losses. N fertilizer management in a greenhouse cropping system should not only identify how to reduce N fertilizer input but should also be more attentive to improving soil fertility with better management of organic manure.

Ren, Tao; Wang, Jingguo; Chen, Qing; Zhang, Fusuo; Lu, Shuchang

2014-01-01

276

Anaerobic digestate from biogas production as a resource for improving soil fertility: effects on crop yield and soil properties  

NASA Astrophysics Data System (ADS)

Soil fertility is fundamental in determining crops productivity in all farming systems. Production of biogas through anaerobic digestion of energy crops generates residues that can represent a valuable resource to sustain and improve soil fertility and to increase soil organic matter content. Residues from anaerobic digestion contain organic fractions and available nutrients, that can thus be returned to the cultivation soil as fertilizer and soil conditioner. However, some unknown aspects of digested residues utilization remain to explore: i) the nutrient supply and the real potential for mineral fertilization substitution, ii) the impact on the structure and functioning of soil microbial communities, iii) the direct and indirect effects on soil structure, organic matter and C mineralization. The aim of the present research was to gain a better understanding of these aspects, evaluating the effects of anaerobic digestate application on soil properties and maize yield. With the main focus of comparing mineral fertilization (250 Kg N ha-1) with digested residues addition (at the dose of 25 % and 50 % of mineral fertilizer), a triplicate sets of plots were designed in a field experiment on a silty-clay loam soil in the southern Po Valley (Italy). The amount of applied residues was calculated according to its N content in order to fertilizer each plots with the same amount of total nitrogen. Residues from digestion showed a N content of 0.4 % (60 % as N-NH4) and a C/N ratio of 3. Changes in soil quality after residues application were studied with a holistic approach, involving microbiological, physical and chemical aspects of soil fertility. In particular, we determined: the abundance and diversity of bacterial and fungal soil communities; the soil organic matter content, its distribution within soil aggregates and the C mineralization potential; cation exchange capacity; the main macro and micro nutrients; bulk density; aggregate stability. No significant differences among treatments were registered in the above ground maize biomass. Molecular analysis conducted on microbial soil communities suggested that the application of digested residues to soil contributes to substantial modifications of both bacterial and fungal community structure. Soil organic C and total N increased in soils treated with digested residues addition, with no significant differences between the two doses of digestate. Cation exchange capacity did not show significant differences among treatments, remaining stable during the maize vegetative cycle. Differently, some variations occurred in the exchangeable cation pool. In particular, K content increased under digestate treatments, while Na and Mg contents increased with time irrespective of the fertilization treatment. No significant variations were observed in soil microelement levels, except for an increase in Zn content at the highest digestate dose. Moreover, digested residue addition had a positive impact on aggregates stability. From the first results, the absence of negative effects in plant productivity and soil fertility after residues application, at both doses, is a promising indication for the potential use of anaerobic digestate as substitute of mineral fertilizers.

Pastorelli, Roberta; Lagomarsino, Alessandra; Vignozzi, Nadia; Valboa, Giuseppe; Papini, Rossella; Fabiani, Arturo; Simoncini, Stefania; Mocali, Stefano; Piccolo, Raimondo

2013-04-01

277

Effect of different kinds of crop residues on aggregate-protected soil organic matter fractions.  

NASA Astrophysics Data System (ADS)

Organic matter content of soils determines many important soil properties, such as soil structure, fertility and water-management. To improve its fertility and quality, returning different kinds of organic matter to soil has a long historical tradition. Ameliorating of soil and enhancing its fertility by enhancing its carbon stock with organic matter incorporation (like farmyard manure, crop residues or green manure) are general practices, but the extent of the amelioration depends much on several factors such as quantity, quality of the used organic matters. Quality of soil organic matters is affected by their chemical build-up, which differs by their origin (i.e. plant species); and their decomposability is affected by particle-size, protection by soil aggregates and the extent of their association to mineral surfaces. In our paper we investigated the effect of three different kinds of organic matter incorporation on aggregate-protected organic matter fractions: (1) Maize stem (M), (2) Wheat straw (W), and (3) Maize stem & Wheat straw (MW). Our samples were originated from Keszthely, Western Hungary, where the texture of the investigated soil is Sandy loam, the type of soil is Eutric Cambisol (soil type FAO), or Alfisol (soil type USDA). SOM fractions might be isolated and measured by physical fractionation of soil (Cambardella and Elliott (1992), Jensen et al. (1992)). Firstly, microaggregates were separated according to their particle-size with physical fractionation (i.e. wet sieving) (Six et al. (2000a)). Each sample was pre-treated by capillary wetting and was sieved for 2 min in an analytic sieve shaker machine with the following aperture sizes: 2 mm, 250 ?m, 53 ?m. Therefore 4 fractions were resulted: (1) the >2000 ?m large macro-, (2) the 250-2000 ?m small macro-, (3) the 53-250 ?m microaggregates, and (4) the

Huisz, A.

2009-04-01

278

Stable isotope analysis reveals whether soil-living elaterid larvae move between agricultural crops  

PubMed Central

Tracking the movement of soil-living herbivores is difficult, albeit important for understanding their spatial ecology as well as for pest management. In this study the movement of Agriotes obscurus larvae between plots harbouring isotopically different plants was examined. Neither between maize and wheat nor between maize and grassland movement could be detected. These data suggest that Agriotes larvae rarely disperse between crops as long as local food supply is sufficient. Moreover, the current approach provides a new means to study the dispersal of soil invertebrates in situ.

Schallhart, N.; Tusch, M.J.; Staudacher, K.; Wallinger, C.; Traugott, M.

2011-01-01

279

Soil respiration, labile carbon pools, and enzyme activities as affected by tillage practices in a tropical rice-maize-cowpea cropping system.  

PubMed

In order to identify the viable option of tillage practices in rice-maize-cowpea cropping system that could cut down soil carbon dioxide (CO2) emission, sustain grain yield, and maintain better soil quality in tropical low land rice ecology soil respiration in terms of CO2 emission, labile carbon (C) pools, water-stable aggregate C fractions, and enzymatic activities were investigated in a sandy clay loam soil. Soil respiration is the major pathway of gaseous C efflux from terrestrial systems and acts as an important index of ecosystem functioning. The CO2-C emissions were quantified in between plants and rows throughout the year in rice-maize-cowpea cropping sequence both under conventional tillage (CT) and minimum tillage (MT) practices along with soil moisture and temperature. The CO2-C emissions, as a whole, were 24 % higher in between plants than in rows, and were in the range of 23.4-78.1, 37.1-128.1, and 28.6-101.2 mg m(-2) h(-1) under CT and 10.7-60.3, 17.3-99.1, and 17.2-79.1 mg m(-2) h(-1) under MT in rice, maize, and cowpea, respectively. The CO2-C emission was found highest under maize (44 %) followed by rice (33 %) and cowpea (23 %) irrespective of CT and MT practices. In CT system, the CO2-C emission increased significantly by 37.1 % with respect to MT on cumulative annual basis including fallow. The CO2-C emission per unit yield was at par in rice and cowpea signifying the beneficial effect of MT in maintaining soil quality and reduction of CO2 emission. The microbial biomass C (MBC), readily mineralizable C (RMC), water-soluble C (WSC), and permanganate-oxidizable C (PMOC) were 19.4, 20.4, 39.5, and 15.1 % higher under MT than CT. The C contents in soil aggregate fraction were significantly higher in MT than CT. Soil enzymatic activities like, dehydrogenase, fluorescein diacetate, and ?-glucosidase were significantly higher by 13.8, 15.4, and 27.4 % under MT compared to CT. The soil labile C pools, enzymatic activities, and heterotrophic microbial populations were in the order of maize?>?cowpea?>?rice, irrespective of the tillage treatments. Environmental sustainability point of view, minimum tillage practices in rice-maize-cowpea cropping system in tropical low land soil could be adopted to minimize CO2-C emission, sustain yield, and maintain soil health. PMID:24609455

Neogi, S; Bhattacharyya, P; Roy, K S; Panda, B B; Nayak, A K; Rao, K S; Manna, M C

2014-07-01

280

Zinc in soils, crops, and meals in the Niger Inland Delta, Mali.  

PubMed

Zinc deficiency is a problem in developing countries and not least so in Africa. This concerns both agriculture and human food provision. Zinc deficiency in soils may severely decrease yields, whereas insufficient zinc in food intake primarily affects the immune defense, notably in children. The present investigation concerned zinc availability in soils, crops, and food in the Niger inland delta in Mali. Agricultural soils are largely deficient in plant-available zinc, however, soils in close vicinity to habitation show elevated zinc concentrations. The zinc concentrations in crops are low; in rice, they are about half of reference ranges. Zinc intake assessed from a number of sampled meals was about half the recommended requirement. When zinc concentration is higher phytate was also high, which made the zinc less available. In spite of a recorded sufficient intake of iron, anemia is common and is most likely because of the high phytate concentration in the cereal-dominated diet. Increasing zinc and iron availability would be possible through the use of malting, fermentation, and soaking in food preparation. Finally, in the long run, any trace element deficiency, especially that of zinc in agricultural soils needs to be amended by addition of appropriate amounts in commercial fertilizers. PMID:19860157

Gårdestedt, Caroline; Plea, Mama; Nilsson, Gertrud; Jacks, Birgitta; Jacks, Gunnar

2009-09-01

281

Effect of sustained saline irrigation on soil salinity and crop yields  

Microsoft Academic Search

Field studies were conducted for a period of ten years (1974 to 1984) on Typic Ustochrept to determine the sustained effects of saline irrigation water electrical conductivity (ECiw) 3.2 dS\\/m, sodium adsorption ratio (SAR) 21 (mmol\\/1)1\\/2 and residual sodium carbonate (RSC) 4me\\/1, on the build up of salinity in the soil profile and yield of crops grown under fixed rice-wheat

M. S. Bajwa; A. S. Josan; G. S. Hira; N. T. Singh

1986-01-01

282

Chlorimuron ethyl sorption and desorption kinetics in soils and herbicide-desiccated cover crop residues  

Microsoft Academic Search

Interaction between a herbicide and plant residue on the soil surface in plant residue management systems such as no-tillage or cover crop is of interest in terms of environmental fate of the herbicide. This study was designed to evaluate sorption and desorption of chlorimuron ethyl {ethyl 2-(((((4- chloro-6-methoxy-2-pyrimidinyl)aminolc~bonyll~olsulfonyllbenzoic acid} in herbicide-desiccated rye (Secale cereale L.) and hairy vetch (Vicia villosa

Krishna N. Reddy; Martin A. Locke; Stephen C. Wagner; Robert M. Zablotowicz; Lewis A. Gaston; Reid J. Smeda

1995-01-01

283

Bacterial Indicator of Agricultural Management for Soil under No-Till Crop Production  

PubMed Central

The rise in the world demand for food poses a challenge to our ability to sustain soil fertility and sustainability. The increasing use of no-till agriculture, adopted in many areas of the world as an alternative to conventional farming, may contribute to reduce the erosion of soils and the increase in the soil carbon pool. However, the advantages of no-till agriculture are jeopardized when its use is linked to the expansion of crop monoculture. The aim of this study was to survey bacterial communities to find indicators of soil quality related to contrasting agriculture management in soils under no-till farming. Four sites in production agriculture, with different soil properties, situated across a west-east transect in the most productive region in the Argentinean pampas, were taken as the basis for replication. Working definitions of Good no-till Agricultural Practices (GAP) and Poor no-till Agricultural Practices (PAP) were adopted for two distinct scenarios in terms of crop rotation, fertilization, agrochemicals use and pest control. Non-cultivated soils nearby the agricultural sites were taken as additional control treatments. Tag-encoded pyrosequencing was used to deeply sample the 16S rRNA gene from bacteria residing in soils corresponding to the three treatments at the four locations. Although bacterial communities as a whole appeared to be structured chiefly by a marked biogeographic provincialism, the distribution of a few taxa was shaped as well by environmental conditions related to agricultural management practices. A statistically supported approach was used to define candidates for management-indicator organisms, subsequently validated using quantitative PCR. We suggest that the ratio between the normalized abundance of a selected group of bacteria within the GP1 group of the phylum Acidobacteria and the genus Rubellimicrobium of the Alphaproteobacteria may serve as a potential management-indicator to discriminate between sustainable vs. non-sustainable agricultural practices in the Pampa region.

Rosa, Silvina M.; Simonetti, Leandro; Duval, Matias E.; Galantini, Juan A.; Bedano, Jose C.; Wall, Luis G.; Erijman, Leonardo

2012-01-01

284

Selenium concentrations of common weeds and agricultural crops grown in the seleniferous soils of northwestern India.  

PubMed

The plants grown in seleniferous soils constitute a major source of toxic selenium levels in the food chain of animals and human beings. Greenhouse and field experiments were conducted to study selenium concentrations of weeds, forages and cereals grown on seleniferous soils located between 31.0417 degrees to 31.2175 degrees N and 76.1363 degrees to 76.4147 degrees E in northwestern India. Eleven winter season (November-April) weed plants were grown in the greenhouse in a soil treated with different levels of selenate-Se. Selenium concentrations of weed plants increased progressively with the levels of selenate-Se in soil. The highest Se concentration was recorded by Silene gallica (246 mgkg(-1)) and the lowest by Avena ludoviciana (47 mgkg(-1)) at 2.5 mg Sekg(-1) soil. A.ludoviciana and Spergula arvensis proved highly tolerant to the presence of 1.25 and 2.5 mg selenate-Sekg(-1) soil and the remaining weeds were sensitive to Se. Dry matter yield of Se-sensitive weed plants was 25 to 62% of the yield in the no-Se control at 1.25mg selenate-Sekg(-1) and 6 to 40% at 2.5mg selenate-Sekg(-1) soil. Other symptoms like change in leaf colour and size, burning of leaf tips and margins, and delayed flowering were also observed due to Se. Dry matter yield of Se-sensitive weed plants expressed as percentage of yield in the no-Se control at both the Se levels was inversely correlated with their Se content (r=-0.731, p<0.01, N=17). Among the weed plants grown in seleniferous soils under field situations, Mentha longifolia accumulated the highest Se (365 mgkg(-1)) and Phalaris minor the lowest (34 mgkg(-1)). Among agricultural crops grown on a naturally contaminated soil in the greenhouse, Se concentrations were the highest for oilseed crops (19-29 mgkg(-1)), followed by legumes (6-13 mgkg(-1)) and cereals (2-18 mgkg(-1)). Helianthus annuus among the oilseed crops, A.ludoviciana among the winter season weeds, M.longifolia among the summer season (May-October) weeds and Cirsium arvense among the perennial weeds can be used for phytoremediation of seleniferous soils as these accumulate the highest amounts of Se. PMID:19800657

Dhillon, Karaj S; Dhillon, Surjit K

2009-12-01

285

Effectiveness of Perennial Vegetation Strips in Reducing Runoff in Annual Crop Production Systems  

NASA Astrophysics Data System (ADS)

In many parts of the world, unprecedented high crop yields have been attained by conversion of native perennial grasslands to intensively managed annual cropping systems. However, these achievements have often been accompanied by significant environmental impacts with far-reaching social and economic costs. Perhaps nowhere is this situation revealed more acutely than in the Midwestern US, where landscape-scale transformation of native tallgrass prairie to rowcrop corn and soybeans has dramatically altered the hydrologic cycle, increased nutrient and sediment loss, and diminished ecosystem services. The objective of this study was to assess the potential for reducing negative impacts of rowcrop agriculture on water quality and flow by incorporating native prairie vegetation in strategic locations within conventional rowcrop agriculture. Specifically, we tested the hypothesis that small amounts of prairie vegetation strategically located in agricultural landscapes would lead to disproportionate benefits by reducing runoff and nutrient and sediment loss. The study was conducted at the Neal Smith National Wildlife Refuge (Iowa), and consisted of a fully balanced, replicated, incomplete block design whereby twelve small experimental catchments (0.43 - 3.19 ha) received four treatments consisting of varying proportions (0%, 10%, and 20%) of prairie vegetation located in different watershed positions (downslope “toe” vs. contour strips). Pre- treatment data were collected in 2005, treatments installed in 2006, and post-treatment responses monitored annually (April-October) thereafter. Volume and rate of surface runoff were measured with an H-Flume installed in each catchment, and automated ISCO samplers used to collect event-based runoff samples that were analyzed for sediment, nitrate (N), and phosphorus (P) concentration. A total of 102 rainfall events were registered during the study period (April-October, 2008 and 2009), accounting for a total rainfall amount of 792 mm and 684 mm, in 2008 and 2009, respectively. Eighty-eight of the rainfall events were runoff-producing in at least one of the watersheds. A highly significant linear relationship between rainfall and runoff was found and the slopes of equations were always higher for 100% crops and lower for watersheds with prairie vegetation. Peak flows occurred earlier and higher peaks were observed in the watersheds with 100% crops than in the mixed crop-prairie watersheds. There was a trend of greatest runoff reduction occurring in watersheds with 10% of prairie in toeslope and 20% of prairie in contour strips, compared to the other treatments. Sediment, N, and P loss was approximately 25, 5.5, and 9 times greater, respectively, from the 100% rowcrop watersheds compared to the mixed crop-prairie watersheds. In conclusion, the results suggest that the incorporation of strategically placed small amounts of diverse perennial vegetation (10% at toeslope and 20% strips) can significantly reduce runoff volume and loss of sediment and nutrients from rowcrop agriculture.

Hernandez-Santana, V.; Zhou, X.; Helmers, M.; Asbjornsen, H.; Kolka, R. K.

2010-12-01

286

A Comparison of Risk and Return Characteristics of Efficient Crop Portfolios for the Brown Soil Zones Saskatchewan and Mecklenburg, Germany  

Microsoft Academic Search

Two efficient farms are constructed for the brown soils of Saskatchewan, Canada and for Mecklenburg, Germany based on producer panels. Both farms feature highly integrated cropping systems which take advantage of cropping synergies. However, farm risk is inherently different between the two because differences in 1) climate that gives rise to very different yield risk and cost structure, and 2)

Richard A. Schoney; Christof Moeller

2005-01-01

287

Cover crop nitrogen availability to conventional and no?till corn: Soil mineral nitrogen, corn nitrogen status, and corn yield  

Microsoft Academic Search

Understanding seasonal soil nitrogen (N) availability patterns is necessary to assess corn (Zea mays L.) N needs following winter cover cropping. Therefore, a field study was initiated to track N availability for corn in conventional and no?till systems and to determine the accuracy of several methods for assessing and predicting N availability for corn grown in cover crop systems. The

Jeffrey D. Vaughan; Greg D. Hoyt; Arthur G. Wollum II

2000-01-01

288

Effect of cover crop on soil physical and chemical properties of an alfisol in the Sudan savannah of Burkina faso  

Microsoft Academic Search

The effect of several leguminous and graminaceous cover crops on soil physical and chemical properties was studied on a moderately eroded Alfisol in the Sudan savannah of Burkina Faso during the growing seasons of 1986 and 1987. Cover crops sown in 1986 were Macroptilium artropurpureum, M. lathyroides, Vigna radiata var. radiata, Cajanus cajan, Alysicarpus vaginalis, Lablab purpureus, Psophocarpus palustris, Digitaria

N. R. Hulugalle

1988-01-01

289

Influence of Cover Crops and Inorganic Nitrogen Fertilization on Tomato and Snap Bean Production and Soil Nitrate Distribution  

Microsoft Academic Search

Commercial vegetable production depends almost solely on inorganic fertilizers. In an era of environmental sensitivity, enrichment of soils with green manures and cover crops may reduce the dependence on these fertilizers while maintaining and enhancing crop yields. The objectives of this research were to determine (1) if supplemental nitrogen (N) at 60 or 120 kg · ha following winter cover

Robert J. Dufault; Dennis R. Decoteau; J. Thomas Garrett; K. Dean Batal; Darbie Granberry; Jeanine M. Davis; Greg Hoyt; Douglas Sanders

2000-01-01

290

Assessing the effect of soil management on soil functioning: a meta-regression analysis on European crop yields under conservation agriculture.  

NASA Astrophysics Data System (ADS)

Many strategies exist to combat soil degradation through erosion and compaction on agricultural fields. One of these strategies is conservation agriculture (CA). Reduced or zero tillage techniques, together with crop residue management and crop rotation are the pillars of CA. The term reduced tillage covers a range of tillage practices but it never involves inverting the soil. In this way, soil disturbance is minimised and crop residues are left on the soil. As CA also requires less wheel traffic that can increase soil bulk density and reduces infiltration rates, CA has the potential to reduce degradation and improve soil functioning. Studies in many European countries have shown that CA can indeed be very effective in combating soil erosion. However, soil and water conservation do not appear as main drivers in farmers' decisions to shift or not to CA. Economic factors tend to be more important, but there are a lot of uncertainties on this domain. Studies show that production costs are mostly reduced, mainly by reduced fuel costs. However, on production outcome, i.e. crop yield, a lot of uncertainties exist. To ensure proper functioning of agricultural soils that are prone to degradation, it is clear that these uncertainties have to be quantified. Many European studies have investigated the effect of reduced soil tillage on crop yields. However, the anecdotic evidence is often contradictory and therefore difficult to interpret. Most of them only cover a small range of field experiments, in one region. We present a meta-regression analysis (47 European studies, 565 observations) that compares crop yields under conventional tillage (CT), reduced tillage (RT) and zero tillage (ZT) techniques. We analysed the possible influence on the relative yield ((RT or ZT)/CT) of crop type, tillage depth, climate, CT yield and length of application of RT/ZT. ZT reduces crop yield on average with 8.5%. However, RT leads to a reduction in crop yields for maize and winter cereals only. By applying a linear mixed model, the importance of tillage depth and crop type as classification effects could be confirmed. Our analysis also allowed to identify some effects that are not always in agreement with common beliefs. For instance, yields under CA tend to decline with time, especially for monoculture maize. An effect of climate on relative crop yields could only be distinguished in the case of zero tillage: there is a positive relationship between crop yield and the seasonal water balance, contradicting the idea that CA is more efficient in dry areas due to more efficient water conservation.

van den Putte, An; Govers, Gerard; Diels, Jan; Gillijns, Katleen; Demuzere, Matthias

2010-05-01

291

Cover crops influence soil properties and tree performance in an organic apple ( Malus domestica Borkh) orchard in northern Patagonia  

Microsoft Academic Search

Little is known about the effects of cover crops on soil properties in organic orchards. To fill this gap, this work aimed\\u000a at examining the effects of several cover crops on soil fertility, nitrate dynamics, populations of nematodes and tree performance\\u000a in an organic orchard of apple cv. Royal Gala\\/EM 26 planted in 1994 at 4 × 2 m. In 1999 the following

E. E. Sánchez; A. Giayetto; L. Cichón; D. Fernández; M. C. Aruani; M. Curetti

2007-01-01

292

Process-based modeling of nitrous oxide emissions from wheat-cropped soils at the subregional scale  

Microsoft Academic Search

Arable soils are a large source of nitrous oxide (N2O) emissions, making up half of the biogenic emissions worldwide. Estimating their source strength requires methods capable of capturing the spatial and temporal variability of N2O emissions, along with the effects of crop management. Here we applied a process-based model, Crop Environmental REsources Synthesis (CERES), with geo-referenced input data on soils,

B. Gabrielle; P. Laville; O. Duval; B. Nicoullaud; J. C. Germon; C. Hénault

2006-01-01

293

The effects of soil sterilisation with steam-air mixtures on the development of some glasshouse crops  

Microsoft Academic Search

The undesirable side effects in lettuce crops grown on soils sterilised at 100°C, do not occur on soils sterilised with steam-air mixtures at 70°C. Both in pot experiments and in field trials, significantly higher yields were obtained on soil sterilised at 70°C than on soil sterilised at 100°C. In the pot experiments the average head weight of lettuce obtained from

C. Sonneveld; S. Voogt

1973-01-01

294

Optimizing the rate and timing of phosphogypsum application to magnesium-affected soils for crop yield and water productivity enhancement  

Microsoft Academic Search

The levels of magnesium (Mg2+) in irrigation waters and soils are increasing in several irrigation schemes worldwide. Excess levels of Mg2+ in irrigation waters and\\/or in soils negatively affect soil physical properties (infiltration rate and hydraulic conductivity) and ultimately crop growth and yield. Although few studies have been undertaken on productivity enhancement of magnesium-affected soils by adding a source of

F. Vyshpolsky; K. Mukhamedjanov; U. Bekbaev; S. Ibatullin; T. Yuldashev; A. D. Noble; A. Mirzabaev; A. Aw-Hassan; M. Qadir

2010-01-01

295

Space agriculture: the effect of micro- and hypogravity on soil hydraulics and biogeochemistry in a bioregenerative soil-based cropping unit  

Microsoft Academic Search

Abstract Increasing interest has developed towards growing plants in soil-based cropping modules as a long-term bioregenerative life support system in space and planetary explorations. Contrary to hydroponics, zeoponics and aeroponics, soil-based cropping would offer an effective approach to sustain food and oxygen production, decompose organic wastes, sequester carbon dioxide, and filter water for the crew. The hydraulic and biogeochemical functioning

F. Maggi; C. E. Pallud

2010-01-01

296

Food safety assessment of planting patterns of four vegetable-type crops grown in soil contaminated by electronic waste activities.  

PubMed

A field experiment was conducted to assess the effect of crop and planting pattern on levels of cadmium (Cd), lead (Pb), and copper (Cu) in crops grown in soil contaminated by electronic waste. The crops were maize (Zea mays L. var. Shentian-1), tomato (Solanum lycopersicum L. var. Zhongshu-4), cabbage (Brassica oleracea L. var. Jingfeng-1), and pakchoi (Brassica chinensis (L.) Makino. var. Youdonger-Hangzhou). The planting patterns were crop monoculture, crop co-planted with a legume, and crop co-planted with another crop. Metal concentrations in the edible parts of the crops varied with types of metals and crops. Pb concentration was higher in leafy vegetables (cabbage and pakchoi) than in maize or tomato, Cd concentration was higher in tomato and pakchoi than in maize or cabbage, and Cu concentration was higher in maize and pakchoi than in tomato or cabbage. Metal concentrations in the edible part were also influenced by planting pattern. Relative to monoculture, co-planting and especially co-planting with Japanese clover tended to decrease Pb accumulation and increase Cd accumulation. According to the maximum permissible concentration (MPC) standard of the National Standard Agency in China, only maize (under all planting patterns) could be safely consumed. Because co-planting tended to increase Cd accumulation even in maize, however, the results suggest that maize monoculture is the optimal crop and planting pattern for this kind of contaminated soil. PMID:22054567

Liu, Ling; Hu, Liangliang; Tang, Jianjun; Li, Yuefang; Zhang, Qian; Chen, Xin

2012-01-01

297

The effects of crop rotation and fertilization on wheat productivity in the Pampean semiarid region of Argentina. 1. Soil physical and chemical properties  

Microsoft Academic Search

Wheat in the semiarid region of Argentina has often been grown as a low-input crop. Rainfall scarcity and distribution are the main characteristics of this region. The knowledge of the combined effects of crop rotation and fertilization on soil physical and chemical properties are the key for a sustainable crop production. Soil properties for an Entic Haplustoll in the semiarid

A. M Miglierina; J. O Iglesias; M. R Landriscini; J. A Galantini; R. A Rosell

2000-01-01

298

Soil microbial biomass, crop yields, and bacterial community structure as affected by long-term fertilizer treatments under wheat-rice cropping  

Microsoft Academic Search

Soil microbial biomass carbon (SMBC) and nitrogen (SMBN), soil microbial community structure, and crop yields were studied in a long-term (1982–2004) fertilization experiment carried out in Suining, Sichuan province of PR China. Eight treatments included three chemical fertilizer (CF) treatments (N, NP, NPK), three CF+farmyard manure (M) treatments (NM, NPM, NPKM), M alone and no fertilizer (CK) as control. The

Yunfu Gu; Xiaoping Zhang; Shihua Tu; Kristina Lindström

2009-01-01

299

Spatial variation in soil penetration resistance according to the structural states of the soil and soybean crop yield  

NASA Astrophysics Data System (ADS)

The soil penetration resistance (PR) is used to identify and characterize soil layers densified by effects of tilling, and the results obtained are related to root growth and crop productivity. The aims of this work were: (i) to analyze the spatial variation in PR through resistance isolines in an Aquic Argiudoll with different long-term cropping sequences under no tillage (NT), (ii) to compare the information generated from the lines with the same PR values with the analysis of the cultural profile and (iii) to study the spatial variability in the PR and the bulk density (BD) in a 10-ha plot, and their relationship with soybean crop yield. An experiment was carried out in an Aquic Argiudoll in 100-m2 plots (4 m wide x 25 m long), with different long-term cropping sequences, under NT for 15 years. The treatments tested were: soybean and maize monocultures, wheat/soybean, wheat/soybean-maize and a permanent pasture as a reference. A digital penetrologger Eijkelkamp ® was used to take 20 measurements of the PR in each plot, through the design of a grid 5 m long and 0.66 m wide, centimeter-wise until 20 cm, totaling n= 400. In addition, an observation well (1 m wide by 30 cm deep) was analyzed by means of the technique of the cultural profiles. Besides, two sampling grids in a 10-ha plot with maize-wheat/soybean sequence were used to measure PR every 30 m and BD every 60 m. The variability in the soil properties was assessed using descriptive statistical analysis, determining normality and spatial variability with the adjustment to the theoretical semivariograms. At 10-15 and 15-20 cm, wheat/soybean-maize and wheat/soybean showed the highest PR values, differentiating from the soybeans and maize monocultures and pasture. The lines with the same PR values allowed observing structural changes in the soil profile, such as surface granular structures and subsequent layers of laminar structure, sometimes discontinuous, from 1.0 to 1.5 MPa between 5 and 8 cm in depth, and massive structures located in the profile up to 2.6 MPa. In the 10-ha plot, the PR identified a hardened layer at 05-12 cm, with a maximum value of 1.45 MPa; the PR also showed greater spatial variation in the plot than the BD, with maximum values of 2.58 MPa and 1.52 g cm-3, respectively. Although with varying thickness, platy structures were present in all the treatments of the crop sequences under NT. The identification of compaction areas at subsurface level, with reduction of macropores, coincided with the traffic. The crop sequences that presented high compaction were wheat/soybean and wheat/soybean-maize, attributable to the greater number of passes of agricultural machinery in the plot. We thus recommend controlled traffic. The results provide tools to identify areas for homogeneous soil management and detect constraints on soybean crop yield.

Wilson, Marcelo; Sasal, María Carolina; Oszust, José; Gabioud, Emmanuel; Melchiori, Ricardo

2013-04-01

300

Effects of Crop Rotation and Irrigation on Verticillium dahliae Microsclerotia in Soil and Wilt in Cauliflower.  

PubMed

ABSTRACT Experiments were conducted in field plots to evaluate the effects of broccoli residue on population dynamics of Verticillium dahliae in soil and on Verticillium wilt development on cauliflower under furrow and subsurface-drip irrigation and three irrigation regimes in 1994 and 1995. Treatments were a factorial combination of three main plots (broccoli crop grown, harvested, and residue incorporated in V.dahliae-infested plots; no broccoli crop or residue in infested plots; and fumigated control plots), two subplots (furrow and subsurface-drip irrigation), and three sub-subplots (deficit, moderate, and excessive irrigation regimes) arranged in a split-split-plot design with three replications. Soil samples collected at various times were assayed for V. dahliae propagules using the modified Anderson sampler technique. Incidence and severity of Verticillium wilt on cauliflower were assessed at 7- to 10-day intervals beginning a month after cauliflower transplanting and continuing until harvest. Number of propagules in all broccoli plots declined significantly (P < 0.05) after residue incorporation and continued to decline throughout the cauliflower season. The overall reduction in the number of propagules after two broccoli crops was approximately 94%, in contrast to the fivefold increase in the number of propagules in infested main plots without broccoli after two cauliflower crops. Disease incidence and severity were both reduced approximately 50% (P < 0.05) in broccoli treatments compared with no broccoli treatments. Differences between furrow and subsurface-drip irrigation were not significant, but incidence and severity were significantly (P < 0.05) lower in the deficit irrigation regime compared with the other two regimes. Abundance of microsclerotia of V. dahliae on cauliflower roots about 8 weeks after cauliflower harvest was significantly (P < 0.05) lower in treatments with broccoli compared with treatments without broccoli. Rotating broccoli with cauliflower and incorporating broccoli residues into the soils is a novel means of managing Verticillium wilt on cauliflower and perhaps on other susceptible crops. This practice would be successful regardless of the irrigation methods or regimes followed on the susceptible crops. PMID:18944816

Xiao, C L; Subbarao, K V; Schulbach, K F; Koike, S T

1998-10-01

301

Energy crop (Sida hermaphrodita) fertilization using digestate under marginal soil conditions: A dose-response experiment  

NASA Astrophysics Data System (ADS)

The global demand for energy security and the mitigation of climate change are the main drivers pushing energy-plant production in Germany. However, the cultivation of these plants can cause land use conflicts since agricultural soil is mostly used for plant production. A sustainable alternative to the conventional cultivation of food-based energy-crops is the cultivation of special adopted energy-plants on marginal lands. To further increase the sustainability of energy-plant cultivation systems the dependency on synthetic fertilizers needs to be reduced via closed nutrient loops. In the presented study the energy-plant Sida hermaphrodita (Malvaceae) will be used to evaluate the potential to grow this high potential energy-crop on a marginal sandy soil in combination with fertilization via digestate from biogas production. With this dose-response experiment we will further identify an optimum dose, which will be compared to equivalent doses of NPK-fertilizer. Further, lethal doses and deficiency doses will be observed. Two weeks old Sida seedlings were transplanted to 1L pots and fertilized with six doses of digestate (equivalent to a field application of 5, 10, 20, 40, 80, 160t/ha) and three equivalent doses of NPK-fertilizer. Control plants were left untreated. Sida plants will grow for 45 days under greenhouse conditions. We hypothesize that the nutrient status of the marginal soil can be increased and maintained by defined digestate applications, compared to control plants suffering of nutrient deficiency due to the low nutrient status in the marginal substrate. The dose of 40t/ha is expected to give a maximum biomass yield without causing toxicity symptoms. Results shall be used as basis for further experiments on the field scale in a field trial that was set up to investigate sustainable production systems for energy crop production under marginal soil conditions.

Nabel, Moritz; Bueno Piaz Barbosa, Daniela; Horsch, David; Jablonowski, Nicolai David

2014-05-01

302

Effects of Cropping Sequences on Population Densities of Meloidogyne hapla and Carrot Yield in Organic Soil.  

PubMed

The influence of various cropping sequences on population densities of Meloidogyne hapla and carrot yield was studied in organic soil under microplot-and field conditions. Spinach, radish, barley, oat, and wheat were poor or nonhosts for M. hapla. Population densities of M. hapla were maintained or increased on cabbage, celery, lettuce, leek, marigold, and potato. Marketable percent-age and root weight of carrots were greater following spinach, oat, radish, and fallow-onion than those following two crops of onion or carrot in microplots. Under field conditions, the carrot-onion-oat-carrot cropping sequence decreased M. hapla population densities and provided a 282% increase in marketable yield of carrot compared to a carrot monoculture. Two consecutive years of onion increased M. hapla population densities causing severe root galling and a 50% yield loss in the following crop of carrot. Based on root-gall indices, carrots could be grown economically for 2 years following radish, spinach, and oat, but not following onion and carrot without the use of nematicides. PMID:19283022

Bélair, G

1992-09-01

303

Enhanced irreversible sorption of carbaryl to soils amended with crop-residue-derived biochar.  

PubMed

The irreversible sorption-desorption of carbaryl in five soil types with crop-residue-derived biochar (CBC) amendment was determined. CBC has lower surface area and micropores volume than wood-based biochar and charcoal. However, CBC amendment (0.5%) still significantly enhanced the hysteresis effect on soils, with a 1.7- to 2.8-fold increase in the hysteresis index (HI) values. The HI values increased exponentially with the increased amount of CBC but decreased exponentially with the increased amount of soil organic matter (SOM%). Furthermore, the irreversible carbaryl sorption (qirr) and the irreversibility index (Iirr) values were proportional to the amount of CBC (0-1.0%) in soils. Likewise, the SOM-rich soil (S3) was washed ten times to reduce its SOM% to evaluate the influence of the dissolved organic matter (DOM) in the soils on the irreversible sorption. The Iirr values of the unamended S3 increased as the number of sorption-desorption cycles increased, whereas those of the 1.0% CBC-amended S3 decreased. In addition, the Iirr values of the unwashed S3 were lower than those of the washed S3. By contrast, the Iirr values of the 1.0% CBC-amended S3 soil were higher in the unwashed samples than in the washed samples. These results suggested that DOM had opposite effects on the irreversible carbaryl sorption by unamended and CBC-amended soils. The DOM release may expose more irreversible adsorption sites in the soils and may cover the surface of the CBC to form a desorption-resistant fraction in its mesopore or macropore regions, thereby preventing the desorption of adsorbed carbaryl molecules. PMID:23711410

Qiu, Yuping; Wu, Minwei; Jiang, Jing; Li, Liang; Sheng, G Daniel

2013-09-01

304

DIVISION S-6—SOIL & WATER MANAGEMENT & CONSERVATION Tillage and Crop Influences on Physical Properties for an Epiaqualf  

Microsoft Academic Search

tillage usually has been found to increase b compared with moldboard and chisel plow (Kitur et al., 1993; Lal, Tillage impacts on soil properties differ among soils. This study 1999). Bulk density usually is lowest immediately after investigated tillage, cropping, and wheel traffic (WT) effects of 13-yr of no-tillage (NT), chisel plow (CP), and moldboard plow (MP) under tillage and

Humberto Blanco-Canqui; C. J. Gantzer; S. H. Anderson; E. E. Alberts

305

A minimum data set for soil quality assessment of wheat and maize cropping in the highlands of Mexico  

Microsoft Academic Search

The objective was to establish a minimum soil quality dataset for a long-term tillage, residue management and rotation trial for wheat (Triticum aestivum L.) and maize (Zea mays L.) production systems. Based on this soil quality evaluation, sustainable management practices could be selected for transferring technologies to farmers in the region. A long-term experiment was conducted with 16 different crop

Bram Govaerts; Ken D. Sayre; Jozef Deckers

2006-01-01

306

Legume cover cropping effects on early growth and soil nitrogen supply in eucalypt plantations in south-western India  

Microsoft Academic Search

Growth and soil N supply in young Eucalyptus tereticornis stands at two sites in Kerala, India, were examined in response to cover cropping with three legume species ( Pueraria phaseoloides, Stylosanthes hamata, and Mucuna bracteata). The effects of legume residues on soil N supply were investigated in a long-term (392 day) laboratory incubation using leaching micro-lysimeters. Residues from the eucalypt and

D. S. Mendham; S. Kumaraswamy; M. Balasundaran; K. V. Sankaran; M. Corbeels; T. S. Grove; A. M. O’Connell; S. J. Rance

2004-01-01

307

Phytoavailability and fractionation of copper, manganese, and zinc in soil following application of two composts to four crops  

Microsoft Academic Search

Two experiments were conducted to evaluate the effect of compost addition to soil on fractionation and bioavailability of Cu, Mn, and Zn to four crops. Soils growing Swiss chard (Beta vulgaris var. cicla L.) and basil (Ocimum basilicum L.) were amended (by volume) with 0, 20, 40, and 60% Source-Separated Municipal Solid Waste (SS-MSW) compost, and dill (Anethum graveolens L.)

Valtcho D. Zheljazkov; Phil R. Warman

2004-01-01

308

The influence of the different members of a crop-rotation system on the biodynamics of soil  

Microsoft Academic Search

Summary The thought that a soil under prevailing climatic conditions receives the most significant impulse from its vegetational cover together with the biochemical activity of micro-organisms living in it, has suggested the study of soil biodynamics under the different members of a crop-rotation system.

F. W. Pauli

1968-01-01

309

Evaluation of soil erosion protective cover by crop residues using vegetation indices and spectral mixture analysis of multispectral and hyperspectral data  

Microsoft Academic Search

Crop residues are efficient in reducing erosion and surface water runoff on agricultural soils. Evaluating the crop residue cover fraction and its spatial distribution is important to scientists involved in the modelling of soil erosion and surface runoff, and also to authorities wishing to assess soil conservation adoption by farmers. This study focuses on the evaluation of four remote sensing

Éric Arsenault; Ferdinand Bonn

2005-01-01

310

Annual soil respiration in broadleaf forests of northern Wisconsin: influence of moisture and site biological, chemical, and physical characteristics  

Microsoft Academic Search

Soil temperature and moisture influence soil respiration at a range of temporal and spatial scales. Although soil temperature and moisture may be seasonally correlated, intra and inter-annual variations in soil moisture do occur. There are few direct observations of the influence of local variation in species composition or other stand\\/site characteristics on seasonal and annual variations in soil moisture, and

Jonathan G. Martin; Paul V. Bolstad

2005-01-01

311

Sweet corn production and efficiency of nitrogen use in high cover crop residue  

Microsoft Academic Search

In the humid, temperate mid-Atlantic area of the USA, crop production that leaves the soil uncovered can lead to undesirable\\u000a soil and nutrient losses to the surrounding Chesapeake Bay watershed. To cope with this issue, winter annual cover crops could\\u000a provide soil cover both during winter months and, as surface residue in no-tillage cropping systems, during summer months.\\u000a Legume cover

John R. Teasdale; Aref A. Abdul-Baki; Yong Bong Park

2008-01-01

312

Simulation of nitrous oxide effluxes, crop yields and soil physical properties using the LandscapeDNDC model in managed ecosystem  

NASA Astrophysics Data System (ADS)

Modeling of nitrous oxide emissions from soil is very complex. Many different biological and chemical processes take place in soils which determine the amount of emitted nitrous oxide. Additionaly, biogeochemical models contain many detailed factors which may determine fluxes and other simulated variables. We used the LandscapeDNDC model in order to simulate N2O emissions, crop yields and soil physical properties from mineral cultivated soils in Poland. Nitrous oxide emissions from soils were modeled for fields with winter wheat, winter rye, spring barley, triticale, potatoes and alfalfa crops. Simulations were carried out for the plots of the Brody arable experimental station of Poznan University of Life Science in western Poland and covered the period 2003 - 2012. The model accuracy and its efficiency was determined by comparing simulations result with measurements of nitrous oxide emissions (measured with static chambers) from about 40 field campaigns. N2O emissions are strongly dependent on temperature and soil water content, hence we compared also simulated soil temperature at 10cm depth and soil water content at the same depth with the daily measured values of these driving variables. We compared also simulated yield quantities for each individual experimental plots with yield quantities which were measured in the period 2003-2012. We conclude that the LandscapeDNDC model is capable to simulate soil N2O emissions, crop yields and physical properties of soil with satisfactorily good accuracy and efficiency.

Nyckowiak, Jedrzej; Lesny, Jacek; Haas, Edwin; Juszczak, Radoslaw; Kiese, Ralf; Butterbach-Bahl, Klaus; Olejnik, Janusz

2014-05-01

313

Remote sensing in Iowa agriculture. [land use, crop identification, and soil mapping  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. Analysis of 1972 single-date coverage indicated that a complete crop classification was not attainable at the test sites. Good multi-date coverage during 1973 indicates that many of the problems encountered in 1972 will be minimized. In addition, the compilation of springtime imagery covering the entire state of Iowa has added a new dimension to interpretation of Iowa's natural resources. ERTS-1 has provided data necessary to achieve the broad synoptic view not attainable through other means. This should provide soils and crop researchers and land use planners a base map of Iowa. Granted and due to the resolution of ERTS-1, not all details are observable for many land use planning needs, but this gives a general and current view of Iowa.

Mahlstede, J. P. (principal investigator); Carlson, R. E.; Fenton, T. E.

1974-01-01

314

Effects of crop abandonment and grazing exclusion on available soil water and other soil properties in a semi-arid Mongolian grassland  

Microsoft Academic Search

Improper cropping and overgrazing have led to land degradation in semi-arid regions, resulting in desertification. During desertification, vegetation changes have been widely observed, and are likely controlled to some extent by soil water. The purpose of this study was to investigate changes in soil physical properties, organic C, and vegetation induced by land-use changes, with special reference to the dynamics

A. Hoshino; K. Tamura; H. Fujimaki; M. Asano; K. Ose; T. Higashi

2009-01-01

315

DNA fingerprinting reveals links among agricultural crops, soil properties, and the composition of soil microbial communities  

Microsoft Academic Search

Rapid methods for characterizing soil microbial communities are essential to assess responses to perturbations and to improved management practices. This study compared the composition of microbial communities in 47 agricultural soil and adjacent land use samples collected in the San Joaquin Valley, CA. Microbial communities were characterized by DNA fingerprinting of the Intergenic Transcribed Spacer (ITS) region, using primers universal

M. J. Johnson; K. Y. Lee; K. M. Scow

2003-01-01

316

Characterization and crop production efficiency of diazotrophic bacterial isolates from coastal saline soils.  

PubMed

Use of eco-friendly area specific salt tolerant bioinoculants is better alternatives to chemical fertilizer for sustainable agriculture in coastal saline soils. We isolated diverse groups of diazotrophic bacteria from coastal saline soils of different forest and agricultural lands in the Sundarbans, West Bengal, India, to study their effect on crop productivity in saline soils. Phenotypic, biochemical and molecular identifications of the isolates were performed. The isolates produced indole acetic acid, phosphatase, and solubilized insoluble phosphates. Sequence analysis of 16S rDNA identified the SUND_BDU1 strain as Agrobacterium and the strains SUND_LM2, Can4 and Can6 belonging to the genus Bacillus. The ARA activity, dinitrogen fixation and presence of nifH genes indicated they were diazotrophs. Field trials with these strains as bioinoculants were carried out during 2007-2009, with rice during August-December followed by Lady's finger during April-June. Microplots, amended with FYM inoculated with four bioinoculants individually were compared against sole FYM (5 t ha(-1)) and a sole chemical fertilizer (60:30:30 kg ha(-1) NPK) treated plot. The strain Can6 was by far the best performer in respect of yield attributes and productivity of studied crops. PMID:21596539

Barua, Shilajit; Tripathi, Sudipta; Chakraborty, Ashis; Ghosh, Sagarmoy; Chakrabarti, Kalyan

2012-01-20

317

Effect of sewage sludge-borne cadmium on crop production and on soil and plant composition  

SciTech Connect

Teller sandy loan (fine-loamy, mixed, thermic, Udic Agriustolls) and Norge loam (fine-silty, mixed, thermic, Udic Paleustolls) were used in a greenhouse study with rates of cadmium (Cd) in sewage sludge. Two sewage sludges were mixed to produce a range of Cd treatments of 7 to 120 mg Cd kg/sup -1/ in a 44 mt ha/sup -1/ sludge treatment rate. Application depths of 0 to 15 cm and 15 to 30 cm for grain sorghum (Sorghum bicolor) and soybean (Glycine max) for two successive crops were included as experimental variables. Statistical design was a lattice square with five replications. Fresh and dry weights of plant materials were determined and analyzed for total content of Fe, Mn, Zn, and Cd after digestion. Soil samples from 0 to 7.5, 7.5 to 15, and 15 to 30 cm depths were taken after the second crop was harvested and analyzed for DTPA extractable Fe, Zn, and Cd. The soil pH and percent organic matter were determined, also, and compared to original soil analysis.

Al-Solaimani, S.G.

1986-01-01

318

Short-term cover crop decomposition in organic and conventional soils: Soil microbial and nutrient cycling indicator variables associated with different levels of soil suppressiveness to Pythium aphanidermatum  

Microsoft Academic Search

Stages of oat-vetch cover crop decomposition were characterized over\\u000a time in terms of carbon and nitrogen cycling, microbial activity and\\u000a community dynamics in organically and conventionally managed soils in a\\u000a field experiment and a laboratory incubation experiment. We subsequently\\u000a determined which variables describing soil microbial community dynamics,\\u000a C and N cycling could be used as predictors of Pythium aphanidermatum\\u000a damping-off

N. J. Grünwald; S. Hu; A. H. C. van Bruggen

2000-01-01

319

Effects of soil and water conservation on crop productivity: Evidences from Anjenie watershed, Ethiopia  

NASA Astrophysics Data System (ADS)

Widespread soil and water conservation activities have been implemented in many parts of eastern Africa to control soil erosion by water and improve land productivity for the last few decades. Following the 1974 severe drought, soil and water conservation became more important to Ethiopia and the approach shifted to watershed based land management initiatives since the 1980s. To capture long-term impacts of these initiatives, a study was conducted in Anjenie Watershed of Ethiopia, assessing fanya juu terraces and grass strips constructed in a pilot project in 1984, and which are still functional nearly 30 years later. Data were collected from government records, field observations and questionnaire surveys administered to 60 farmers. Half of the respondents had terraced farms in the watershed former project area (with terrace technology) and the rest were outside the terraced area. The crops assessed were teff, barley and maize. Cost-benefit analyses were used to determine the economic benefits with and without terraces, including gross and net profit values, returns on labour, water productivity and impacts on poverty. The results indicated that soil and water conservation had improved crop productivity. The average yield on terraced fields was 0.95 t ha?1 for teff (control 0.49), 1.86 t ha?1 for barley (control 0.61), and 1.73 t ha?1 for maize (control 0.77). The net benefit was significantly higher on terraced fields, recording US 20.9 (US ?112 control) for teff, US 185 (US ?41 control) for barley and US ?34.5 (US ? 101 control) ha?1 yr?1 for maize. The returns on family labour were 2.33 for barley, 1.01 for teff, and 0.739 US per person-day for maize grown on terraced plots, compared to US 0.44, 0.27 and 0.16 per person-day for plots without terraces, respectively. Using a discount rate of 10%, the average net present value (NPV) of barley production with terrace was found to be about US 1542 over a period of 50 years. In addition, the average financial internal rate of return (FIRR) was 301%. Other long-term impacts of terracing included farmers' growing of maize on terraced fields as a result of water conservation. Currently, farmers also grow barley on terraced fields for two crop seasons per year unlike the experiences on farms without terraces. Household incomes and food security had improved and soil erosion drastically reduced. Many farmers had adopted terracing doubling the original area under the soil conservation pilot project and consequently improving environmental conservation in the watershed.

Adgo, Enyew; Teshome, Akalu

2014-05-01

320

Sustainability of soil fertility and the use of lignocellulosic crop harvest residues for the production of biofuels: a literature review.  

PubMed

Use of lignocellulosic crop harvest residues for liquid or gaseous biofuel production may impact soil quality, long-term soil fertility and the major determinants of the latter, stocks of soil organic carbon and nutrients. When soil organic carbon stocks of mineral cropland soils are to be maintained, there is scope for the removal of lignocellulosic harvest residues in several systems with much reduced tillage or no tillage. The scope for such removal might be increased when suitably treated residues from the conversion of harvest residues into biofuel are returned to cropland soils. For mineral cropland soils under conventional tillage, the scope for the production of liquid biofuels from harvest residues is likely to be less than in the case of no-till systems. When fertility of cropland soils is to be sustainable, nutrients present in suitably treated biofuel production residues have to be returned to these soils. Apparently, the actual return of carbon and nutrients present in residues of biofuel production from crop harvest residues to arable soils currently predominantly concerns the application of digestates of anaerobic digestion. The effects thereof on soil fertility and quality need further clarification. Further clarification about the effects on soil fertility and quality of chars and of co-products of lignocellulosic ethanol production is also needed. PMID:24350430

Reijnders, L

2013-01-01

321

Understanding the potential impact of climate change on long term soil carbon dynamics in tropical cropping systems - evidence from West Africa  

NASA Astrophysics Data System (ADS)

Long term experiments offer a unique opportunity to assess sustainability and temporal dynamics of biogeochemical cycles in agriculture, as well as the gradual impact on these of relatively slow processes such as climate change. Two long term experiments on annual cropping systems representing locally common crop rotations and cultural practices were established on two contrasting agroecological zones in Ivory Coast (in 1971) and in Mali (in 1965). These experiments were designed to assess the long-term productivity of these systems under different organic matter and nutrient management regimes, applying organic and mineral soil amendments alone or in combination. Organic soil amendments - such as animal manure, compost or plant material collected from the surroundings - were included in the experiments with the double purpose of adding nutrients for immediate crop production and adding organic matter inputs to the soil to restore (or maintain) its organic C content. Here, we provide an overview of the major trends in crop productivity and soil organic C observed in these experiments that illustrates the potential impact of climate change on the effectiveness of different measures to sustain agricultural productivity. Materials and methods Both experiments compared crop productivity on control plots without any soil amendment versus plots receiving organic matter, mineral fertilisers or both combined. The experiment at Gagnoa (southern Ivory Coast) was conducted during 23 years in a zone characterised by a bimodal rainfall regime (c. 1300 mm year-1) that allows two cropping seasons per year (Alfisols 15% clay). Every year maize was planted during the first rainy season. Organic matter was added as compost at a rate of 10 t ha-1 year-1, with or without application of 160 kg N ha-1 year-1 in mineral fertiliser (Chabalier, 1986). The experiment at N'Tarla (southern Mali) was conducted during 24 years in a zone of mono-modal rainfall (c. 900 mm year-1); Alfisols 5% clay), and consisted of quadrennial/triennial rotations of cotton (2x), sorghum and groundnuts. Organic matter was added as straw collected from adjacent fallow fields at a rate of 15 t ha-1 every three years, with and without application of N-P-K mineral fertilisers at an average rate of 30, 20 and 40 kg ha-1 year-1, respectively (Kone, 1989). In both experiments crop residues were incorporated in the soil every year. Results At both sites yields of the main crops were larger than the control on plots receiving organic and/or mineral soil amendments, and in both experiments crop yields were comparable when either organic or mineral fertilisers were applied. In the case of maize, partial additive effects of organic and mineral fertilisers applied in combination were observed. In the case of cotton, plots receiving only mineral fertilisers tended to yield less than those receiving organic amendments during the second half of the experiment. Soil organic C declined in control plots and in those receiving only mineral fertilisers in Gagnoa (Ivory Coast), and less markedly also in N'Tarla (Mali). Addition of 10 t ha-1 year-1 of organic matter with or without addition of mineral N led to greater soil C contents in Gagnoa, but yet a decline was observed over the 23 years. Addition of 15 t ha-1 year-1 of organic matter with or without fertilisers in N'Tarla had only a marginal effect on soil C content. In spite of the observed decline in soil C contents, maize yields tended to increase in Gagnoa in the last years of the experiment. Discussion Important differences were observed between sites in the size of the stocks and flows of carbon in and through the cropping system, which were the result of a different agroecological potential. Maize is a C4 species that produces large amounts of biomass; two cropping seasons per year allow fixing greater amounts of C from the atmosphere through photosynthesis. Although soil C inputs via crop residues were thus larger in Gagnoa, climatic conditions at this site favoured also a faster mineralisation of soil organic matter. The addit

Cretenet, Michel; Tittonell, Pablo; Guibert, Herve

2010-05-01

322

Winter soil CO 2 efflux and its contribution to annual soil respiration in different ecosystems of a forest-steppe ecotone, north China  

Microsoft Academic Search

Most soil respiration measurements are conducted during the growing season. In tundra and boreal forest ecosystems, cumulative winter soil CO2 fluxes are reported to be a significant component of their annual carbon budgets. However, little information on winter soil CO2 efflux is known from mid-latitude ecosystems. Therefore, comparing measurements of soil respiration taken annually versus during the growing season will

Wei Wang; Shushi Peng; Tao Wang; Jingyun Fang

2010-01-01

323

Influence of soil properties and climate characteristics on transpirable soil water for two varieties with differences in their crop cycle timing  

NASA Astrophysics Data System (ADS)

This paper presents an analysis of soil water content in two vineyards planted with Chardonnay and Cabernet Sauvignon in the Penedès Designation of Origin (DO). Climate is Mediterranean with maritime influence. The main soil types are Typic Xerorthent and Fluventic Haploxerept and soil is bare most of the time to avoid the competition of weeds for water. The plantation pattern was uniform in both cultivars, 1.3*3m. Soil moisture was analysed at each area from 10 to 90 cm every 20 cm, using TDF probes during two crop growing cycles (2010-2012). Soil water balance for years with different rainfall amount and distribution throughout the year was simulated using the Soil and Water Assessment Tool (SWAT). Differences in phenology of about one month existed among both varieties. In addition, the soil hydrological properties variability, resulted from land levelling operations before vineyard establishment, affects crop's soil water availability. These two facts made that, under the same rainfall amount and distribution, water available during the crop cycle were different for both varieties. The transpirable soil water fraction reached very low values, close to 0.1, particularly in the variety with early phenology timing. This pattern was repeated in different years depending on rainfall distribution, which affected grape production with significant yield reductions (up to 38% in relation to the average were found in some years).

Ramos, Maria C.

2014-05-01

324

Water Erosion in Relation with Soil Management System and Crop Sequence during 20 Years on an Inceptisol in South Brazil  

NASA Astrophysics Data System (ADS)

Soil erosion still remains persistent at the world scale, even if big efforts have been done to control and reduce it, mainly using soil crop residues to protect soil surface. Although in South Brazil the main management system for most crops is no tillage and direct drilling, water erosion prevails as the most important soil erosion type, which is due both, to the high erosivity and the evenly distribution of rainfall over the year. Moreover, some crops are still grown under soil tillage systems consisting of ploughing, harrowing and less frequently chiselling. Starting 1992, a field experiment under natural rainfall has been conducted on an Inceptisol located in Lages, Santa Catarina State, Brazil, which objective was to assess rainfall water erosion. Two soil cover conditions and four soil management systems were studied: I) a crop rotation, which included oats (Avena strigosa), soybean (Glycine max), common vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and common bean (Phaseolus vulgaris) under the following soil management types: 1) ploughing plus two levelling operations (CT), chiselling plus levelling (RT) and direct drilling with no tillage (NT), and II) bare soil (BS) without crop cover tilled by ploughing plus two levelling. In more than 90% of the study cases, soil losses were collected for single rain events with erosive power, whose erosivity was calculated. Total rain recorded during the 20 year experimental period was approximately 66,400 mm, which is equivalent to roughly 105,700, MJ mm ha-1 h-1 (EI30), whereas soil losses in the BS treatment were higher than 1,700 t.ha-1. On average, soil losses under RT treatment showed a 92% reduction in relation with BS, whereas under CT the reduction in relation to BS was about 66%. Soil management by direct drilling (NT) was the most efficient system to minimize water erosion, as soil losses decreased about 98% when compared with BS. Moreover, soil management systems with a crop rotation, i.e., RT, CT, and NT, showed a lower efficiency in the reduction of water losses with regard to the efficiency of soil losses decrease. So many rainfall events during our experimental period showed similar water losses for all the management and crop systems, which was mainly true for rainfalls causing high volumes of runoff and with a small time interval between successive events. During the autumn-winter seasons water losses were lower than in the spring-summer seasons, whereas greater soil losses in the spring-summer season were solely recorded in the CT and BS treatments. Heavy water losses by runoff recorder under conservation tillage, specifically in the NT management system suggest the need for adoption of additional structural conservation practices, such as for example terracing, in order to supplement the positive effect of soil cover by crop residues in controlling water erosion. Soil losses showed a positive correlation with rainfall erosivity and the significance of this relationship decreased as the efficiency of soil management system for the control of soil erosion increased.

Bertol, I.; Schick, J.; Barbosa, F. T.; Paz-Ferreiro, J.; Flores, M. T.; Paz González, A.

2012-04-01

325

Arsenic behaviour from groundwater and soil to crops: impacts on agriculture and food safety.  

PubMed

High levels of As in groundwater commonly found in Bangladesh and other parts of Asia not only pose a risk via drinking water consumption but also a risk in agricultural sustainability and food safety. This review attempts to provide an overview of current knowledge and gaps related to the assessment and management of these risks, including the behaviour of As in the soil-plant system, uptake, phytotoxicity, As speciation in foods, dietary habits, and human health risks. Special emphasis has been given to the situation in Bangladesh, where groundwater via shallow tube wells is the most important source of irrigation water in the dry season. Within the soil-plant system, there is a distinct difference in behaviour of As under flooded conditions, where arsenite (AsIII) predominates, and under nonflooded conditions, where arsenate (AsV) predominates. The former is regarded as most toxic to humans and plants. Limited data indicate that As-contaminated irrigation water can result in a slow buildup of As in the topsoil. In some cases the buildup is reflected by the As levels in crops, in others not. It is not yet possible to predict As uptake and toxicity in plants based on soil parameters. It is unknown under what conditions and in what time frame As is building up in the soil. Representative phytotoxicity data necessary to evaluate current and future soil concentrations are not yet available. Although there are no indications that crop production is currently inhibited by As, long-term risks are clearly present. Therefore, with concurrent assessments of the risks, management options to further prevent As accumulation in the topsoil should already have been explored. With regard to human health, data on As speciation in foods in combination with food consumption data are needed to assess dietary exposure, and these data should include spatial and seasonal variability. It is important to control confounding factors in assessing the risks. In a country where malnutrition is prevalent, levels of inorganic As in foods should be balanced against the nutritional value of the foods. Regarding agriculture, As is only one of the many factors that may pose a risk to the sustainability of crop production. Other risk factors such as nutrient depletion and loss of organic matter also must be taken into account to set priorities in terms of research, management, and overall strategy. PMID:17193736

Heikens, Alex; Panaullah, Golam M; Meharg, Andy A

2007-01-01

326

Water erosion during a 17-year period under two crop rotations in four soil management systems on a Southbrazilian Inceptisol  

NASA Astrophysics Data System (ADS)

Soil erosion still remains a persistent issue in the world, and this in spite of the efforts to ameliorate soil management systems taken into account the point of view of environmental protection against soil losses. In South Brazil water erosion is mainly associated to rainfall events with a great volume and high intensity, which are more or less evenly distributed all over the year. Nowadays, direct drilling is the most widely soil management system used for the main crops of the region. However, some crops still are grown on conventionally tilled soils, which means mainly ploughing and harrowing and less frequently chisel ploughing. In Lages-Santa Catarina State, Brazil, a plot experiment under natural rain was started in 1992 on an Inceptisol with the aim of quantifying soil and water losses. Treatments included bare and vegetated plots. The crop succession was: oats (Avena strigosa), soybean (Glycine max), vetch (Vicia sativa), maize (Zea mays), fodder radish (Raphanus sativus) and beans (Phaseolus vulgaris). Soil tillage systems investigated in this study were: i) conventional tillage (CT), ii) reduced tillage (MT), iii) no tillage (NT) under crop rotation and iv) conventional tillage on bare soil (BS). Treatments CT and BS involved ploughing plus twice harrowing, whereas MT involved chisel ploughing plus harrowing. Rainfall erosivity from January 1 1992 to December 31 2009 was calculated. Soil losses from the BS treatment along the 17 year study period were higher than 1200 Mg ha-1. Crop cover significantly reduced erosion, so that under some crops soil losses in the CT treatment were 80% lower than in the BS treatment. In turn soil losses in the MT treatment, where tillage was performed by chiselling and harrowing, were on average about 50% lower than in the CT treatment. No tillage was the most efficient soil management system in reducing soil erosion, so that soil losses in the NT treatment were about 98% lower than in the BS treatment. The three vegetated treatments, CT, MT and NT showed a lower efficiency in reducing water losses than soil losses. Water losses by runoff during a number of events were of the same order of magnitude for all the management systems studied here; which was mainly true when the volume of rainfall was high and the lag between successive events was small. In general, soil losses in the autumn-winter seasons were lower than under the spring-summer seasons. Soil losses showed a positive correlation with rainfall erosivity. However, the degree of dependence between these two variables decreased as the efficiency of soil management in controlling soil erosion increased. The large soil and water losses in the BS and CT treatments suggest that there is a need to implement soil conservation measures in the study region. In this context soil conservation would take advantage from soil cover by previous crop residue as well as from terrace building. Acknowledgement: This work was partly supported by Spanish Ministry of Education (Project CGL2005-08219-C02).

Bertol, Ildegardis; Vidal Vázquez, Eva; Paz Ferreiro, Jorge

2010-05-01

327

The role of vegetation and soil properties on the spatio-temporal variability of the surface soil moisture in a maize-cropped field  

NASA Astrophysics Data System (ADS)

Soil moisture dynamics are affected by complex interactions among several factors. Understanding the relative importance of these factors is still an important challenge in the study of water fluxes and solute transport in unsaturated media. In this study, the spatio-temporal variability of surface soil moisture was investigated in a 10 ha flat cropped field located in northern Italy. Soil moisture was measured on a regular 50 × 50 m grid on seven dates during the growing season. For each measurement campaign, the spatial variability of the soil moisture was compared with the spatial variability of the soil texture and crop properties. In particular, to better understand the role of the vegetation, the spatio-temporal variability of two different parameters - leaf area index and crop height - was monitored on eight dates at different crop development stages. Statistical and geostatistical analysis was then applied to explore the interactions between these variables. In agreement with other studies, the results show that the soil moisture variability changes according to the average value within the field, with the standard deviation reaching a maximum value under intermediate mean soil moisture conditions and the coefficient of variation decreasing exponentially with increasing mean soil moisture. The controls of soil moisture variability change according to the average soil moisture within the field. Under wet conditions, the spatial distribution of the soil moisture reflects the variability of the soil texture. Under dry conditions, the spatial distribution of the soil moisture is affected mostly by the spatial variability of the vegetation. The interaction between these two factors is more important under intermediate soil moisture conditions. These results confirm the importance of considering the average soil moisture conditions within a field when investigating the controls affecting the spatial variability of soil moisture. This study highlights the importance of considering the spatio-temporal variability of the vegetation in investigating soil moisture dynamics, especially under intermediate and dry soil moisture conditions. The results of this study have important implications in different hydrological applications, such as for sampling design, ranking stability application, indirect measurements of soil properties and model parameterisation.

Baroni, G.; Ortuani, B.; Facchi, A.; Gandolfi, C.

2013-05-01

328

Soil Labile Organic Matter under Long-term Crop Rotation System  

NASA Astrophysics Data System (ADS)

Temperate grassland soils, typically Mollisols, have remained agriculturally productive with limited inputs for many years, despite the mining of energy and nutrients reserves contained within the soil organic fraction (Janzen, 1987; Tiessen et al., 1994). Such system can be considered resilient, at least initially, but one must question for how long such systems can be sustained. Effect of long-term land-use on biologically active fractions of soil organic matter is not well understood. Investigations were conducted in more than 40-year static experiments in northern Kazakhstan. We examined five fallow-wheat (Triticum aestivum L.) cropping systems with different frequencies of the fallow phase: continuous wheat (CW), 6-y rotation (6R), 4-y rotation (4R), 2-y rotation (2R) and continuous fallow (CF). A unique sample from nationally protected virgin steppe near the experimental field was sampled for comparison with long-term cultivated soils. Soil samples were collected from the two phases of each rotation, pre- and post-fallow, and analyzed for biological soil properties that are potentially mineralizable C (PMC), potentially mineralizable N (PMN), microbial biomass C (MBC) and N (MBN) and "light fraction" C (LFC) and N (LFN). Potentially mineralizable C was inversely proportional to the frequency of fallow and was highest in CW. Potentially mineralizable N was more responsive to rotation phase than other indices of SOM. Light fraction OM was negatively correlated to the frequency of fallow and was higher in pre-fallow than in post-fallow phases. All studied biological characteristics were drastically greater in the soil from the natural steppe. The results suggested that the yearly input of plant residues in a less frequently fallowed system built up more PMC, whereas PMN was closely correlated to recent inputs of substrate added as plant residue. We concluded that a frequent fallowing for long period may deplete SOM via accelerated mineralization. The results may provide prediction of SOM response to fallow frequency in wheat-fallow based cropping systems in semi-arid regions.

Saljnikov, E.

2009-04-01

329

Climate Change and Sustainability for the High Plains Aquifer: Quantifying Impacts to Water, Soil, and Crop Yields (Invited)  

NASA Astrophysics Data System (ADS)

Water usage across much of the High Plains aquifer is far from sustainable due to extensive pumping for irrigated crop production. Climate changes are expected to increase the water challenges for such regions due to projected increases in both temperature and variability in precipitation. In addition, increasing temperatures will reduce crop yields unless new land management strategies and crop cultivars are developed to offset such changes. In this project we use process-based hydrology and crop models to synthesize a vast array of data including remote sensing products (Leaf Area Index, Digital Elevation Model, land cover maps, Crop Data Layers, and NEXRAD precipitation estimates), and station data (e.g., soil property maps, climate observations, and water levels). We use these models to predict groundwater levels, streamflows, and crop yields across the entire High Plains Aquifer and compare simulated results to decades of measured flow, water level, and county crop yield data. We quantify the relative importance of historic changes in climate, land cover, and land management practices on flows and levels, and then simulate the impacts of projected changes in climate on water resources and crops. We also examine the potential for various management strategies to move toward sustainable water resources and crop yields across this important agricultural area.

Hyndman, D. W.; Kendall, A. D.; Basso, B.; Whittemore, D. O.; Butler, J. J.

2013-12-01

330

Phosphorus benefits from grain-legume crops to subsequent maize grown on acid soils of southern Cameroon  

Microsoft Academic Search

We conducted field experiments over 2 years on two acid soils of southern Cameroon to test whether efficient uptake and use\\u000a of phosphorus (P) from less available sources by grain legume genotypes could benefit subsequent rotational maize. We grew\\u000a two crops each year. For the first crop we grew 4 genotypes of soybean and of cowpea, plus maize. For the second

M. Jemo; R. C. Abaidoo; C. Nolte; M. Tchienkoua; N. Sanginga; W. J. Horst

2006-01-01

331

Modelling crop canopy and residue rainfall interception effects on soil hydrological components for semi-arid agriculture  

NASA Astrophysics Data System (ADS)

Crop canopies and residues have been shown to intercept a significant amount of rainfall. However, rainfall or irrigation interception by crops and residues has often been overlooked in hydrologic modelling. Crop canopy interception is controlled by canopy density and rainfall intensity and duration. Crop residue interception is a function of crop residue type, residue density and cover, and rainfall intensity and duration. We account for these controlling factors and present a model for both interception components based on Merriam's approach. The modified Merriam model and the current modelling approaches were examined and compared with two field studies and one laboratory study. The Merriam model is shown to agree well with measurements and was implemented within the Agricultural Research Service's Root Zone Water Quality Model (RZWQM). Using this enhanced version of RZWQM, three simulation studies were performed to examine the quantitative effects of rainfall interception by corn and wheat canopies and residues on soil hydrological components. Study I consisted of 10 separate hypothetical growing seasons (1991-2000) for canopy effects and 10 separate non-growing seasons (1991-2000) for residue effects for eastern Colorado conditions. For actual management practices in a no-till wheat-corn-fallow cropping sequence at Akron, Colorado (study II), a continuous 10-year RZWQM simulation was performed to examine the cumulative changes on water balance components and crop growth caused by canopy and residue rainfall interception. Finally, to examine a higher precipitation environment, a hypothetical, no-till wheat-corn-fallow rotation scenario at Corvallis, Oregon, was simulated (study III). For all studies, interception was shown to decrease infiltration, runoff, evapotranspiration from soil, deep seepage of water and chemical transport, macropore flow, leaf area index, and crop/grain yield. Because interception decreased both infiltration and soil evapotranspiration, no significant change in soil water storage was simulated. Nonetheless, these findings and the new interception models are significant new contributions for hydrologists. Published in 2006 John Wiley & Sons, Ltd.

Kozak, Joseph A.; Ahuja, Lajpat R.; Green, Timothy R.; Ma, Liwang

2007-01-01

332

CONTENT AND REMOVAL OF Cu AND Zn WITH HARVESTED CROPS GROWN ON SOIL FERTILIZED WITH COMPOSTED MUNICIPAL SEWAGE SLUDGE  

Microsoft Academic Search

The purpose of the study has been to determine the direct and residual effect of far- myard manure and composts made from sewage sludge on the content and uptake of cop- per and zinc by crops growing in a four-field crop rotation system. In 2004-2007, a field experiment was established on proper grey-brown podzolic soil, originating from light boul- der

Teresa Bowszys; Jadwiga Wierzbowska; Justyna Bowszys

2009-01-01

333

Carbon sequestration in dryland soils and plant residue as influenced by tillage and crop rotation.  

PubMed

Long-term use of conventional tillage and wheat (Triticum aestivum L.)-fallow systems in the northern Great Plains have resulted in low soil organic carbon (SOC) levels. We examined the effects of two tillage practices [conventional till (CT) and no-till (NT)], five crop rotations [continuous spring wheat (CW), spring wheat-fallow (W-F), spring wheat-lentil (Lens culinaris Medic.) (W-L), spring wheat-spring wheat-fallow (W-W-F), and spring wheat-pea (Pisum sativum L.)-fallow (W-P-F)], and Conservation Reserve Program (CRP) planting on plant C input, SOC, and particulate organic carbon (POC). A field experiment was conducted in a mixture of Scobey clay loam (fine-loamy, mixed, Aridic Argiborolls) and Kevin clay loam (fine, montmorillonitic, Aridic Argiborolls) from 1998 to 2003 in Havre, MT. Total plant biomass returned to the soil from 1998 to 2003 was greater in CW (15.5 Mg ha(-1)) than in other rotations. Residue cover, amount, and C content in 2004 were 33 to 86% greater in NT than in CT and greater in CRP than in crop rotations. Residue amount (2.47 Mg ha(-1)) and C content (0.96 Mg ha(-1)) were greater in NT with CW than in other treatments, except in CT with CRP and W-F and in NT with CRP and W-W-F. The SOC at the 0- to 5-cm depth was 23% greater in NT (6.4 Mg ha(-1)) than in CT. The POC was not influenced by tillage and crop rotation, but POC to SOC ratio at the 0- to 20-cm depth was greater in NT with W-L (369 g kg(-1) SOC) than in CT with CW, W-F, and W-L. From 1998 to 2003, SOC at the 0- to 20-cm depth decreased by 4% in CT but increased by 3% in NT. Carbon can be sequestered in dryland soils and plant residue in areas previously under CRP using reduced tillage and increased cropping intensity, such as NT with CW, compared with traditional practice, such as CT with W-F system, and the content can be similar to that in CRP planting. PMID:16825454

Sainju, Upendra M; Lenssen, Andrew; Caesar-Thonthat, Thecan; Waddell, Jed

2006-01-01

334

Elevated atmospheric COâ and soil nutrients alter competitive performance of California annual grassland species  

Microsoft Academic Search

Atmospheric COâ and soil nutrients altered interspecific competitive performance of three grassland annuals, all exhibiting the Câ metabolic pathway. Plantago erecta, an herbaceous dicot dominant in low-fertility serpentine grassland, was the superior interspecific competitor at low soil nutrients. Bromus hordeaceus, an introduced grass dominant in higher fertility sandstone grassland, was the superior interspecific competitor at high soil nutrients. Interspecific competitive

H. L. Reynolds; F. S. Chapin; C. B. Field

1995-01-01

335

Changes in soil carbon cycling accompanying conversion of row-crop fields to grazing dairy pastures  

NASA Astrophysics Data System (ADS)

Increasingly, the dairy industry in the eastern US is transitioning from total confinement dairy systems (TCD) toward pasture-based, management intensive grazing dairy (MiGD) systems. This transition is driven by the fact that MiGDs require substantially less operating capital and are more economically efficient than TCD systems. Consequently, the impact of this transition and shift in land-use practice on carbon dynamics may be considerable. Land-use in a Management intensive Grazing Dairy (MiGD) system is fundamentally different than conventional confinement dairies and conventional no-till pastures. The forage system involves rotational grazing at optimal digestibility, when the plants are immature (~20-days) and consequently protein-rich. MiGD cows spend >90% of their time in the field and deposit > 90% of their waste directly to the soil surface. Thus, little above ground plant residues are directly returned to the soil, but rather substantial C inputs derive from bovine manure. We sampled a MiGD-chronosequence of row-crop to MiGD conversion established in 2007 in eastern Georgia. All soils across the MiGD-chronosequence, all occur in relative (40 km) close proximity to one another, are deep, well-drained, fine and fine sandy loam Ultisols formed on Coastal Plain sediments. Prior to MiGD established, the soils were farmed for > 50 yrs using conventional tillage techniques. Our current sampling to 1m depths captures fields at 0, 2, 3, and 5 yrs since conversion. Total soil carbon (C) and the carbon concentration of the clay fraction increased following conversion, with the greatest increases occurring between 3 and 5 yrs since conversion. These C increases were limited to the upper 40cm of the soil, with minimal change occurring at depth. Characterization of the protein and ligand content of these soils via 13C NMR and chemolytic techniques as a function of soil particle density and size is in progress and will be presented along with estimates of carbon dioxide and methane fluxes across the MiGD chronosequence. Our broad goal is to quantify ruminal methane emissions and changes to soil C-stocks and stability associated with this land-use shift. Our preliminary data suggest such a land-use change will likely improve soil health and increase C-stocks. Balancing this against potential increases in methane emissions is a key knowledge gap for future southeastern U.S. C-cycling estimates.

Thompson, A.; Kramer, M. G.; Hill, N.; Machmuller, M. B.; Cyle, K.

2011-12-01

336

Rehabilitating acid soils for increasing crop productivity through low-cost liming material.  

PubMed

Productivity of red and lateritic soils is low because of their acidity and deficiencies in few essential nutrients viz., nitrogen, phosphorus, calcium, zinc, boron, molybdenum etc. We compared the effectiveness of basic slag, a low-cost liming material, with that of calcite as an ameliorant for these soils using mustard followed by rice as test crops. Experiments were conducted with three levels of each of basic slag and calcite along with a control on farmers' fields at 14 different locations. Influence of farmyard manure (FYM) and poultry manure (PM) on the effectiveness of the slag was also tested. On an average, basic slag performed better than calcite in increasing yields of both mustard and rice and left over higher amounts of available Ca, Si and Zn in residual soils. The slag also improved N, P, K and Ca nutrition of mustard and Si and Zn nutrition of rice with a favorable benefit:cost (B:C) ratio over the calcite (4.82 vs. 1.44). Effectiveness of the basic slag improved when it was applied in combination with FYM or PM (B:C, 5.83 and 6.27). Basic slag can, therefore, be advocated for use in the acidic red and lateritic soils for economically improving their productivity. PMID:20659758

Bhat, Javid Ahmad; Kundu, Manik Chandra; Hazra, Gora Chand; Santra, Gour Hari; Mandal, Biswapati

2010-09-15

337

Feed the crop not the soil: rethinking phosphorus management in the food chain.  

PubMed

Society relies heavily on inorganic phosphorus (P) compounds throughout its food chain. This dependency is not only very inefficient and increasingly costly but is depleting finite global reserves of rock phosphate. It has also left a legacy of P accumulation in soils, sediments and wastes that is leaking into our surface waters and contributing to widespread eutrophication. We argue for a new, more precise but more challenging paradigm in P fertilizer management that seeks to develop more sustainable food chains that maintain P availability to crops and livestock but with reduced amounts of imported mineral P and improved soil function. This new strategy requires greater public awareness of the environmental consequences of dietary choice, better understanding of soil-plant-animal P dynamics, increased recovery of both used P and unutilized legacy soil P, and new innovative technologies to improve fertilizer P recovery. In combination, they are expected to deliver significant economic, environmental, and resource-protection gains, and contribute to future global P stewardship. PMID:24840064

Withers, Paul J A; Sylvester-Bradley, Roger; Jones, Davey L; Healey, John R; Talboys, Peter J

2014-06-17

338

Bare soil erosion modelling with rainfall simulations: experiments on crop and recently burned areas  

NASA Astrophysics Data System (ADS)

The use of numerical models is of fundamental importance in the comprehension and prediction of soil erosion. At the very basis of the calibration process of the numerical models are the direct measurements of the governing parameters, carried out during field or laboratory tests. To measure and model soil erosion rainfall simulations can be used, that allow the reproduction of project rainfall having chosen characteristics of intensity and duration. The main parameters that rainfall simulators can measure are hydraulic conductivity, parameters of soil erodibility, rate and features of splash erosion, discharge coefficient and sediment yield. Other important parameters can be estimated during the rainfall simulations through the use of photogrammetric instruments able to memorize high definition stereographic models of the soil plot under analysis at different time steps. In this research rainfall simulator experiments (rse) were conducted to measure and quantify runoff and erosion processes on selected bare soil plots. The selected plots are located in some vineyards, olive groves and crops in central Italy and in some recently burned areas in north-central Portugal, affected by a wildfire during early July 2005 and, at the time, largely covered by commercial eucalypt plantations. On the Italian crops the choice of the rainfall intensities and durations were performed on the basis of the previous knowledge of the selected test areas. The procedure was based on an initial phase of soil wetting and a following phase of 3 erosion cycles. The first should reproduce the effects of a normal rainfall with a return time of 2 years (23 mm/h). The second should represent a serious episode with a return time of 10 years (34 mm/h). The third has the objective to reproduce and understand the effects of an intense precipitation event, with a return time of 50 years (41 mm/h). During vineyards experiments some photogrammetric surveys were carried out as well. In the Portugal burned areas, to measure the influence of rain intensities, two rainfall simulations have been carried out simultaneously, one with an intensity of 45 mm/h and one with 85 mm/h. In both cases, before the experiments, soil and vegetation cover description have been made and soil samples have been taken. During the simulations soil samples leaving the parcels were taken at suitable time intervals to measure the sediment yield and the runoff. The rse data have been thought to provide a sufficient basis for erosion modelling at the small-plot scale and, through upscaling, for predicting erosion rates at the slope scale. For this purpose two soil erosion models, WEPP and MEFIDIS, have been selected and then compared. The comparison has shown a certain degree of uncertainty in numeric erosion prediction, due to the non linearity of the overland erosion processes, and to technical and conceptual difficulties, including the data collection. In the following laboratory phase high resolution (2 by 2 mm) DEMs of the vineyards plot are being produced for each meaningful processing phase. The digital elevation models will then be analysed to asses calibration parameters such as soil roughness (expressed by standard deviation of elevations, fractal dimension and local relief energy), soil and sediment transfer (hypsometric curves, local elevation and volume differences) and rill network evolution (Horton ordering, stream lengths, contributing area, drainage density, Hack's law)

Catani, F.; Menci, S.; Moretti, S.; Keizer, J.

2006-12-01

339

Effects of Legume Live-Mulch on Crop Performance, Soil Available Nitrogen and Crop N Status in Intensive Tropical Vegetable Production  

Microsoft Academic Search

In an attempt to introduce legume green manure to intensive tropical vegetable production, we studied the effects of live-mulch. Soil nitrogen, crop-N status, and yields were closely monitored in a continuous, year-round vegetable sequence from 1992 to 1995 in the rice-based lowland environment of southern Taiwan. When live-mulch was newly established at high density, vegetable yields were negatively affected. With

V. Kleinhenz; W. H. Schnitzler; D. J. Midmore

1997-01-01

340

Soil carbon and nitrogen variations in wheat-corn double cropping systems under long-term fertilization in China (Invited)  

NASA Astrophysics Data System (ADS)

Long-term field measurements of soil organic carbon (SOC) and total nitrogen (TN) are crucial for understanding soil carbon and nitrogen cycles. In this study, we analyze SOC and TN dynamics at four long-term experiment sites under wheat-corn cropping rotation in East China. Here we choose a control (no fertilization) and two fertilization treatments: chemical fertilization (NPK) and chemical fertilization with manure (NPKM). Our study shows that both SOC and TN decrease with soil depth, which leads to similar values for C/N ratio along soil profile. Long-term fertilization effects on SOC and TN concentrations occur primarily in the surface soil (0-20 cm). Soil organic carbon appears to be sustained over time in the wheat-corn cropping system at most sites, even under no fertilization. Both SOC and TN concentrations of the surface soils are relative stable in the NPK treatments at the Changping and Zhengzhou sites but rise significantly at the Yangling site. However, TN concentration shows a declining trend in the NPK treatment at the Qiyang site. The NPKM treatment increases SOC and TN concentrations in the surface soil depth. The exception is that soil TN concentration at the Qiyang site shows little change over time, fluctuating between 1.05 and 1.48 g kg-1. As a result, at the Qiyang site, surface soil C/N ratio increase significantly over time in the NPK/NPKM treatments. Soil organic carbon and nitrogen dynamics are coupling at the Changping, Zhengzhou, and Yangling sites but uncoupling at the Qiyang site. Fig. 1. Soil organic carbon (SOC) and total nitrogen (TN) dynamics under long-term corn-wheat cropping system at the (a) Changping , (b) Zhengzhou, (c) Yangling and (d) Qiyang. Table 1. The experimental locations and climate characteristics. data from China meteorological sharing service system, http://cdc.cma.gov.cn/

Cong, R.; Xu, M.; Wang, X.; Zhang, W.

2010-12-01

341

Spatial and temporal monitoring of soil water content with an irrigated corn crop cover using surface electrical resistivity tomography  

NASA Astrophysics Data System (ADS)

A nondestructive and spatially integrated multielectrode method for measuring soil electrical resistivity was tested in the Beauce region of France during a period of corn crop irrigation to monitor soil water flow over time and in two-dimensional (2-D) with simultaneous measurements of soil moisture and thermal profiles. The results suggested the potential of surface electrical resistivity tomography (ERT) for improving soil science and agronomy studies. The method was able to produce a 2-D delimitation of soil horizons as well as to monitor soil water movement. Soil drainage through water uptake by the roots, the progression of the infiltration front with preferential flow zones, and the drainage of the plowed horizon were well identified. At the studied stage of corn development (3 months) the soil zones where infiltration and drainage occurred were mainly located under the corn rows. The structural soil characteristics resulting from agricultural practices or the passage of agricultural equipment were also shown. Two-dimensional sections of soil moisture content were calculated using ERT. The estimates were made by using independently established "in situ" calibration relationships between the moisture and electrical resistivity of typical soil horizons. The thermal soil profile was also considered in the modeling. The results showed a reliable linear relationship between the calculated and measured water contents in the crop horizon. The precision of the calculation of the specific soil water content, quantified by the root mean square error (RMSE), was 3.63% with a bias corresponding to an overestimation of 1.45%. The analysis and monitoring of the spatial variability of the soil moisture content with ERT represent two components of a significant tool for better management of soil water reserves and rational irrigation practices.

Michot, Didier; Benderitter, Yves; Dorigny, Abel; Nicoullaud, Bernard; King, Dominique; Tabbagh, Alain

2003-05-01

342

Carbon sequestration in soybean crop soils: the role of hydrogen-coupled CO2 fixation  

NASA Astrophysics Data System (ADS)

Conversion of native vegetation to agricultural land in order to support the world's growing population is a key factor contributing to global climate change. However, the extent to which agricultural activities contribute to greenhouse gas emissions compared to carbon storage is difficult to ascertain, especially for legume crops, such as soybeans. Soybean establishment often leads to an increase in N2O emissions because N-fixation leads to increased soil available N during decomposition of the low C:N legume biomass. However, soybean establishment may also reduce net greenhouse gas emissions by increasing soil fertility, plant growth, and soil carbon storage. The mechanism behind increased carbon storage, however, remains unclear. One explanation points to hydrogen coupled CO2 fixation; the process by which nitrogen fixation releases H2 into the soil system, thereby promoting chemoautotrophic carbon fixation by soil microbes. We used 13CO2 as a tracer to track the amount and fate of carbon fixed by hydrogen coupled CO2 fixation during one-year field and laboratory incubations. The objectives of the research are to 1) quantify rates of 13CO2 fixation in soil collected from a field used for long-term soybean production 2) examine the impact of H2 gas concentration on rates of 13CO2 fixation, and 3) measure changes in ?13C signature over time in 3 soil fractions: microbial biomass, light fraction, and acid stable fraction. If this newly-fixed carbon is incorporated into the acid-stable soil C fraction, it has a good chance of contributing to long-term soil C sequestration under soybean production. Soil was collected in the field both adjacent to root nodules (nodule soil) and >3cm away (root soil) and labelled with 13CO2 (1% v/v) in the presence and absence of H2 gas. After a two week labelling period, ?13C signatures already revealed differences in the four treatments of bulk soil: -17.1 for root, -17.6 for nodule, -14.2 for root + H2, and -6.1 for nodule + H2. Labelled soil was then placed in nylon mesh bags and buried in the field at a depth of 15cm in a soybean field at the Central Experiment Farm in Ottawa, Ontario. Samples will be removed at intervals of 1,2,3,6,9,12, and 15 months, and the ?13C of three soil fractions will be examined to reveal changes in carbon storage over time. Our results will provide insights into the fate of carbon fixed during hydrogen coupled CO2 fixation, and demonstrate whether this CO2 fixation can contribute to the long-term greenhouse gas balance of soybean production systems.

Graham, A.; Layzell, D. B.; Scott, N. A.; Cen, Y.; Kyser, T. K.

2011-12-01

343

Alternative soil quality indices for evaluating the effect of intensive cropping, fertilisation and manuring for 31 years in the semi-arid soils of India.  

PubMed

Soil quality assessment provides a tool for evaluating the sustainability of alternative soil management practices. Our objective was to develop the most sensitive soil quality index for evaluating fertilizer, farm yard manure (FYM), and crop management practices on a semiarid Inceptisol in India. Soil indicators and crop yield data from a long-term (31 years) fertilizer, manure, and crop rotation (maize, wheat, cowpea, pearl millet) study at the Indian Agricultural Research Institute (IARI) near New Delhi were used. Plots receiving optimum NPK, super optimum NPK and optimum NPK + FYM had better values for all the parameters analyzed. Biological, chemical, and physical soil quality indicator data were transformed into scores (0 to 1) using both linear and non-linear scoring functions, and combined into soil quality indices using unscreened transformations, regression equation, or principal component analysis (PCA). Long-term application of optimum inorganic fertilizers (NPK) resulted in higher soil quality ratings for all methods, although the highest values were obtained for treatment, which included FYM. Correlations between wheat (Triticum aestivum L.) yield and the various soil quality indices showed the best relationship (highest r) between yield and a PCA-derived SQI. Differences in SQI values suggest that the control (no NPK, no manure) and N only treatments were degrading, while soils receiving animal manure (FYM) or super optimum NPK fertilizer had the best soil quality, respectively. Lower ratings associated with the N only and NP treatments suggest that one of the most common soil management practices in India may not be sustainable. A framework for soil quality assessment is proposed. PMID:17457684

Masto, Reginald Ebhin; Chhonkar, Pramod K; Singh, Dhyan; Patra, Ashok K

2008-01-01

344

Co-composting of acid waste bentonites and their effects on soil properties and crop biomass.  

PubMed

Acid waste bentonite is a byproduct from vegetable oil bleaching that is acidic (pH < 3.0) and hydrophobic. These materials are currently disposed of in landfills and could potentially have a negative impact on the effective function of microbes that are intolerant of acidic conditions. A study was undertaken using three different sources of acid waste bentonites, namely soybean oil bentonite (SB), palm oil bentonite (PB), and rice bran oil bentonite (RB). These materials were co-composted with rice husk, rice husk ash, and chicken litter to eliminate their acid reactivity and hydrophobic nature. The organic carbon (OC) content, pH, exchangeable cations, and cation exchange capacity (CEC) of the acid-activated bentonites increased significantly after the co-composting phase. In addition, the hydrophobic nature of these materials as measured using the water drop penetration time (WDPT) decreased from >10 800 s to 16 to 80 s after composting. Furthermore, these composted materials showed positive impacts on soil physical attributes including specific surface area, bulk density, and available water content for crop growth. Highly significant increases in maize biomass (Zea mays L.) production over two consecutive cropping cycles was observed in treatments receiving co-composted bentonite. The study clearly demonstrates the potential for converting an environmentally hazardous material into a high-quality soil conditioner using readily available agricultural byproducts. It is envisaged that the application of these composted acid waste bentonites to degraded soils will increase productivity and on-farm income, thus contributing toward food security and poverty alleviation. PMID:17071900

Soda, Wannipa; Noble, Andrew D; Suzuki, Shinji; Simmons, Robert; Sindhusen, La-Ait; Bhuthorndharaj, Suwannee

2006-01-01

345

EDGA amendment of slightly heavy metal loaded soil affects heavy metal solubility, crop growth and microbivorous nematodes but not bacteria and herbivorous nematodes  

Microsoft Academic Search

Phytoextraction of heavy metals is a promising technology to remediate slightly and moderately contaminated soils. To enhance crops' uptake of heavy metals, chelates such as EDGA are being tested as soil additives. Heavy metal loaded EDGA can affect soil organisms such as bacteria and nematodes in various ways: directly via the soil solution surrounding the organisms and indirectly by changing

L. A. Bouwman; J. Bloem; P. F. A. M. Römkens; J. Japenga

2005-01-01

346

Modeling crop production on the soil-like substrate in CELSS  

NASA Astrophysics Data System (ADS)

Use of plants and soils in bioregenerative life support systems (BLSS) is accompanied by mod-eling of nutrient dynamics and gas exchange to analyze data and plan the experiments. In this connection a mathematical model, based on a deterministic differential equation framework, was developed. Our simulations were validated by comparing their predictions with the results obtained during the laboratory experiments with wheat (Triticum aestivum) grown on the soil-like substrate (SLS). The components of the model were the atmospheric carbon dioxide, humus, mineral nitrogen, microbial biomass and extracellular enzymes of SLS as well as the foliage, stems, roots, grains, straw and root exudates of wheat. Impact of photoperiod, daily photosynthetic photon flux, atmospheric volume, carbon and nitrogen content of SLS, decom-position rate of SLS organic matter on the crop production was simulated. When available SLS nitrogen content was sufficient and circulating carbon mass of BLSS was constant, the increase of light intensity from the certain level provoked the decrease of plant harvest index. Decompo-sition rate of SLS organic matter could be increased under nitrogen limiting conditions owing to active synthesis of extracellular microbial enzymes. Possible applications of the modeling for the improvement of plant growing in BLSS are discussed. Keywords: wheat, soil-like substrate, modeling, nitrogen

Polonskiy, Vadim; Manukovsky, Nickolay; Kovalev, Vladimir

347

Growth of Crops on Fly Ash Treated Soils: Relationship Between Crop Yield and Variation in Chemical Properties as Well as Leaching of Elements from Fly Ash/Soil Mixture.  

National Technical Information Service (NTIS)

As a part of effective utilization and mass disposal of fly ash, this study aimed at examining relationship among growth and yield of crops grown on the fly ash treated fluvial soil, absorption of inorganic elements and variation of chemical properties of...

M. Aoki T. Umezawa A. Nakaoka T. Seki

1987-01-01

348

Dynamic Model for the Effects of Soil P and Fertilizer P on Crop Growth, P Uptake and Soil P in Arable Cropping: Experimental Test of the Model for Field Vegetables  

Microsoft Academic Search

In a previous paper (Greenwood et al. Annals of Botany88: 279–291, 2001), we described a mechanistic model that calculates the effects of extractable soil P and fertilizer P on daily increments in dry matter yield and P uptake of field crops. This paper describes the calibration of that model for six different species and subsequent tests of the calibrated model

D. J. Greenwood; D. A. Stone; T. V. Karpinets

2001-01-01

349

Crop yield and soil water restoration on 9-year-old alfalfa pasture in the semiarid Loess Plateau of China  

Microsoft Academic Search

The alfalfa pastureland in the semiarid Loess Plateau region of Northwest China usually has dry soil layers. A field experiment was conducted from October 2000 to October 2004 to examine soil water recovery and crop productivity on a 9-year-old alfalfa pasture. This experiment included six treatments: alfalfa pasture for 10–14 years, a conventional farming system without prior alfalfa planting, and

Xiao-Ling Wang; Guo-Jun Sun; Yu Jia; Feng-Min Li; Jin-Zhang Xu

2008-01-01

350

Soil carbon and nitrogen variations in wheat-corn double cropping systems under long-term fertilization in China (Invited)  

Microsoft Academic Search

Long-term field measurements of soil organic carbon (SOC) and total nitrogen (TN) are crucial for understanding soil carbon and nitrogen cycles. In this study, we analyze SOC and TN dynamics at four long-term experiment sites under wheat-corn cropping rotation in East China. Here we choose a control (no fertilization) and two fertilization treatments: chemical fertilization (NPK) and chemical fertilization with

R. Cong; M. Xu; X. Wang; W. Zhang

2010-01-01

351

Effect of continuous compost application on humus composition and nitrogen fertility of soils in a field subjected to double cropping  

Microsoft Academic Search

We investigated the effect of continuous compost application on humus composition and N fertility of soils in a field subjected to double cropping (paddy rice and barley) for 25 years. Soil samples were collected from three different plots: (a) No-NF, fertilizer containing P and K but no N; (b) F, fertilizer containing N, P, and K; and (c) F+C, fertilizer plus

Haruo Shindo; Osamu Hirahara; Miho Yoshida; Akio Yamamoto

2006-01-01

352

Plant-Based Assessment of Inherent Soil Productivity and Contributions to China's Cereal Crop Yield Increase since 1980  

PubMed Central

Objective China’s food production has increased 6-fold during the past half-century, thanks to increased yields resulting from the management intensification, accomplished through greater inputs of fertilizer, water, new crop strains, and other Green Revolution’s technologies. Yet, changes in underlying quality of soils and their effects on yield increase remain to be determined. Here, we provide a first attempt to quantify historical changes in inherent soil productivity and their contributions to the increase in yield. Methods The assessment was conducted based on data-set derived from 7410 on-farm trials, 8 long-term experiments and an inventory of soil organic matter concentrations of arable land. Results Results show that even without organic and inorganic fertilizer addition crop yield from on-farm trials conducted in the 2000s was significantly higher compared with those in the 1980s — the increase ranged from 0.73 to 1.76 Mg/ha for China’s major irrigated cereal-based cropping systems. The increase in on-farm yield in control plot since 1980s was due primarily to the enhancement of soil-related factors, and reflected inherent soil productivity improvement. The latter led to higher and stable yield with adoption of improved management practices, and contributed 43% to the increase in yield for wheat and 22% for maize in the north China, and, 31%, 35% and 22% for early and late rice in south China and for single rice crop in the Yangtze River Basin since 1980. Conclusions Thus, without an improvement in inherent soil productivity, the ‘Agricultural Miracle in China’ would not have happened. A comprehensive strategy of inherent soil productivity improvement in China, accomplished through combining engineering-based measures with biological-approaches, may be an important lesson for the developing world. We propose that advancing food security in 21st century for both China and other parts of world will depend on continuously improving inherent soil productivity.

Fan, Mingsheng; Lal, Rattan; Cao, Jian; Qiao, Lei; Su, Yansen; Jiang, Rongfeng; Zhang, Fusuo

2013-01-01

353

7 CFR 205.203 - Soil fertility and crop nutrient management practice standard.  

Code of Federal Regulations, 2010 CFR

...prohibited for use in organic crop production; and (5) A plant or...allowed for use in organic crop production established in § 205.601...allowed for use in organic crop production; (2) Sewage sludge (biosolids) as defined...

2013-01-01

354

Remote sensing in Iowa agriculture. [cropland inventory, soils, forestland, and crop diseases  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. Results include the estimation of forested and crop vegetation acreages using the ERTS-1 imagery. The methods used to achieve these estimates still require refinement, but the results appear promising. Practical applications would be directed toward achieving current land use inventories of these natural resources. This data is presently collected by sampling type surveys. If ERTS-1 can observe this and area estimates can be determined accurately, then a step forward has been achieved. Cost benefit relationship will have to be favorable. Problems still exist in these estimation techniques due to the diversity of the scene observed in the ERTS-1 imagery covering other part of Iowa. This is due to influence of topography and soils upon the adaptability of the vegetation to specific areas of the state. The state mosaic produced from ERTS-1 imagery shows these patterns very well. Research directed to acreage estimates is continuing.

Mahlstede, J. P. (principal investigator); Carlson, R. E.

1973-01-01

355

Effects of different potato cropping system approaches and water management on soilborne diseases and soil microbial communities.  

PubMed

Four different potato cropping systems, designed to address specific management goals of soil conservation, soil improvement, disease suppression, and a status quo standard rotation control, were evaluated for their effects on soilborne diseases of potato and soil microbial community characteristics. The status quo system (SQ) consisted of barley underseeded with red clover followed by potato (2-year). The soil-conserving system (SC) featured an additional year of forage grass and reduced tillage (3-year, barley/timothy-timothy-potato). The soil-improving system (SI) added yearly compost amendments to the SC rotation, and the disease-suppressive system (DS) featured diverse crops with known disease-suppressive capability (3-year, mustard/rapeseed-sudangrass/rye-potato). Each system was also compared with a continuous potato control (PP) and evaluated under both irrigated and nonirrigated conditions. Data collected over three potato seasons following full rotation cycles demonstrated that all rotations reduced stem canker (10 to 50%) relative to PP. The SQ, SC, and DS systems reduced black scurf (18 to 58%) relative to PP; SI reduced scurf under nonirrigated but not irrigated conditions; and scurf was lower in DS than all other systems. The SQ, SC, and DS systems also reduced common scab (15 to 45%), and scab was lower in DS than all other systems. Irrigation increased black scurf and common scab but also resulted in higher yields for most rotations. SI produced the highest yields under nonirrigated conditions, and DS produced high yields and low disease under both irrigation regimes. Each cropping system resulted in distinctive changes in soil microbial community characteristics as represented by microbial populations, substrate utilization, and fatty acid methyl-ester (FAME) profiles. SI tended to increase soil moisture, microbial populations, and activity, as well result in higher proportions of monounsaturated FAMEs and the FAME biomarker for mycorrhizae (16:1 ?6c) relative to most other rotations. DS resulted in moderate microbial populations and activity but higher substrate richness and diversity in substrate utilization profiles. DS also resulted in relatively higher proportions of FAME biomarkers for fungi (18:2 ?6c), actinomycetes, and gram-positive bacteria than most other systems, whereas PP resulted in the lowest microbial populations and activity; substrate richness and diversity; proportions of monounsaturated and polyunsaturated FAME classes; and fungal, mycorrhizae, and actinomycete FAME biomarkers of all cropping systems. Overall, soil water, soil quality, and soilborne diseases were all important factors affecting productivity, and cropping systems addressing these constraints improved production. Cropping system approaches will need to balance these factors to achieve sustainable production and disease management. PMID:20839965

Larkin, Robert P; Honeycutt, C Wayne; Griffin, Timothy S; Olanya, O Modesto; Halloran, John M; He, Zhongqi

2011-01-01

356

Insecticide soil persistence and efficiency in cauliflower field crops: Influence of organic fertilizer and organic matter properties  

Microsoft Academic Search

Cauliflower crops were treated some days after planting against the root fly by pouring onto soil around the plant stem an emulsion of chlorpyrifos or of carbofuran in water. The fields were divided into plots; each plot was treated with one of the organic fertilizers: cow manure, city refuse compost, or mushroom cultivation compost; there were also control plots not

Jean Rouchaud; Fabrice Gustin; Marc Metsue; Roland Touillaux; Frans van de Steene; Christian Pelerents; Joel Gillet; Frans Benoit; Norbert Ceustermans

1992-01-01

357

Salinity evolution and crop response to secondary soil salinity in two agro-climatic zones in Lebanon  

Microsoft Academic Search

This paper reviews the human impact on land degradation through the integrated effect of fertilization and irrigation on secondary salinization for the different cropping patterns and agro-climatic zones of Lebanon. Agricultural operations in the semiarid northern areas of Lebanon are characterized by intensive open field and low tunnel production. Soil degradation has occurred because of the combined effect of mismanaged

T. Darwish; T. Atallah; M. El Moujabber; N. Khatib

2005-01-01

358

Long-term effect of tillage, nitrogen fertilization and cover crops on soil organic carbon and total nitrogen content  

Microsoft Academic Search

No-tillage, N fertilization and cover crops are known to play an important role in conserving or increasing SOC and STN but the effects of their interactions are less known.In order to evaluate the single and combined effects of these techniques on SOC and STN content under Mediterranean climate, a long term experiment started in 1993 on a loam soil (Typic

Marco Mazzoncini; Tek Bahadur Sapkota; Paolo Bàrberi; Daniele Antichi; Rosalba Risaliti

2011-01-01

359

Allelopathic potential of rhizosphere soil of Croton bonplandianum on growth and establishment of some crop and weed plants  

Microsoft Academic Search

This experiment was carried out to study various biological and ecological features of Croton bonplandianum Baill and physico-chemical characteristics of its rhizosphere soil, and determine the effect on the growth of some crop and weed plants that is Triticum aestivum L., Brassica rapa L., Brassica oleracea var. botrytis L. and Spinacea oleracea L., Melilotus alba Medik., Vicia sativa L., and

Swapnal Sisodia; M. Badruzzaman Siddiqui

360

Soil type, management history and current resource allocation: Three dimensions regulating variability in crop productivity on African smallholder farms  

Microsoft Academic Search

Soil fertility varies markedly within and between African smallholder farms, both as a consequence of inherent factors and differential management. Fields closest to homesteads (homefields) typically receive most nutrients and are more fertile than outlying fields (outfields), with implications for crop production and nutrient use efficiencies. Maize yields following application of 100kgNha?1 and different rates and sources of P were

S. Zingore; H. K. Murwira; R. J. Delve; K. E. Giller

2007-01-01

361

Effect of Direct and Residual Effects of Different Sulfur Fertilizers on Groundnut and Wheat Cropping System on Typic Haplaquent Soils  

Microsoft Academic Search

A field experiment was conducted on sulfur deficient soil during kharif dry seasons of 1993, 1994, and 1995 to study the comparative efficacy of selected sources of sulfur to groundnut (Arachis hypogaea L.). The results of the experiment were tested on farm trial in cultivator's field during the kharif season of 1999. The yield of groundnut crop in experimental field

B. Prasad

2003-01-01

362

Arylsulphatase activity of different latosol soils of Ghana cropped to cocoa ( Theobroma cacao ) and coffee ( Coffea canephora var. robusta )  

Microsoft Academic Search

A study was undertaken to investigate arylsulphatase activity in 15 soils cropped to cocoa (Theobroma cacao) and coffee (Coffea canephora var. robusta) in Ghana. The arylsulphatase activity was correlated positively and significantly with organic C, total N, and cation exchange capacity, and correlated negatively with acetate soluble sulphate. The enzyme was deactivated at an incubation temperature of over 60°C. Preheating

M. R. Appiah; Y. Ahenkorah

1989-01-01

363

An annual model of SSM/I radiobrightness for dry soil  

NASA Technical Reports Server (NTRS)

An annual model is presented of the temperature structure within a homogeneous, dry soil halfspace that is subject to both diurnal and annual insolation, radiant heating from the atmosphere, sensible heat exchange with the atmosphere, and radiant cooling. The thermal constitutive properties of the soil are assumed to be constant so that the heat flow equation can be solved analytically. For computational economy, a variable time interval Laplace transform method is developed to predict the temperature.

Liou, Yuei-An; England, A. W.

1992-01-01

364

Modeling soil water movement with water uptake by roots  

Microsoft Academic Search

Soil water movement with root water uptake is a key process for plant growth and transport of water and chemicals in the soil-plant\\u000a system. In this study, a root water extraction model was developed to incorporate the effect of soil water deficit and plant\\u000a root distributions on plant transpiration of annual crops. For several annual crops, normalized root density distribution

Jinquan Wu; Renduo Zhang; Shengxiang Gui

1999-01-01

365

Physiological Responses to Tillage Systems, Cover Crops, and Residue Management  

Microsoft Academic Search

Tillage refers to mechanical manipulation of the soil, and a tillage system refers to a specific set of operations that manipulate\\u000a the soil to produce a crop. Tillage operations modify the edaphic environment of cotton and may thus affect physiological\\u000a determinants of yield. Winter annual cover crops and management of their residue may also affect the growth, development,\\u000a and yields

C. O. Gwathmey; J. F. Bradley; A. Y. Chambers; D. D. Howard; D. D. Tyler

366

Potential of very high spatial resolution Pleiades images for discriminating between crops at early growth stage and bare agricultural soils  

NASA Astrophysics Data System (ADS)

This study was carried out in the framework of the Optical and Radar Federated Earth Observation (ORFEO) accompaniment program of the French Space Agency (CNES). It is also part of the other projects (Prostock-Gessol3, BASC-SOCSENSIT) aiming at spatially monitoring the effects of exogenous organic matter land application on soil organic carbon sequestration, and necessitating for this purpose the gathering of spatial data about crops and crop successions as inputs into mechanistic crop models. The aim of this study was to assess the contribution of very high spatial resolution (VHSR) Pleiades images (2 m -spatial resolution) to the mapping of different crops at various growth stages and various bare soil surface conditions related to tillage operations over an agricultural region in the western peri-urban suburbs of Paris: the Versailles plain (Yvelines, France). About 300 field observations describing soil surface conditions or crop phenological stages were collected at ~150 agricultural fields spread over 21 km², synchronously with the Pleiades images acquisitions of 3 and 24 April 2013. Field data were GIS-structured and used as a basis for delimitating within-field training and test zones. The performance of various classifiers was compared either on the spectral bands with or without NDVI or on the principal components of a series of spectral and textural features of an object-based classifier (ENVI FX®): the Bayesian maximum likelihood classifier (ML), the neural network classifier (NN), the support vector machine classifier with polynomial function kernel (SVM). The overall accuracy of the SVM classifier computed on the 4 spectral bands and the NDVI and followed by a median filter and class recombination according to crops reached about 78% for the Pleiades image of 3 April and 82% for that of 24 April. Tillage operations were very well detected (>77%, user's or producer's accuracies) as well as winter cereals (>70%, user's or producer's accuracies). Both Pleiades images enabled to perfectly discriminate between early stage winter cereals and bare cropped soils. They brought unique information about within-field spatial heterogeneity of crop varieties, seedbed preparation and crop development stages and enabled to detect practices of organic amendment application.

Vaudour, Emmanuelle; Noirot-Cosson, Paul-Emile; Membrive, Olivier; Hadjar, Dalila

2014-05-01

367

Application of the Tasseled Cap concept to simulated thematic mapper data. [transformation for MSS crop and soil imagery  

NASA Technical Reports Server (NTRS)

Thematic Mapper signal counts in the six reflective bands (i.e., excluding the thermal band) are simulated using field and laboratory spectrometer measurements of a variety of crops, crop conditions, and soil types. The Dave atmospheric model and prelaunch sensor characteristics comprise the other components of the simulation. The simulated data are found to occupy essentially three dimensions, two of which are equivalent to the MSS Tasseled Cap Greennes and Brightness features, and a third which is substantially influenced by the mid-infrared bands of the TM. This new dimension is primarily related to soil characteristics, including soil moisture. The nature and characteristics of each dimension are discussed, as are some of the expected information gains (over MSS data) resulting from the additional dimensionality of the data.

Crist, E. P.; Cicone, R. C.

1984-01-01

368

Availability of cadmium to rats from crops grown on cadmium-enriched soil  

SciTech Connect

The research was initiated to enhance understanding of the availability to animals of Cd present in edible plants. Such information is of considerable importance since agricultural crops can accumulate high concentrations of the metal when grown in certain soils or with sewage sludge as a fertilizer. Edible plants were labeled with /sup 109/Cd by growing them on /sup 109/CdCl/sup 2/ treated soil. The availability of /sup 109/Cd to male and female rats was then determined by feeding semisynthetic diets containing either freeze-dried radioactive spinach, lettuce, soybean, carrots, tomatoes, or wheat flour, or comparable nonradioactive plant powders spiked with /sup 109/CdCl/sup 2/. Retention of /sup 109/Cd by liver and kidney was determined after a 14-day feeding period. With the exception of spinach, Cd accumulation by rats was not found to be significantly influenced by the form of Cd in the diet whether supplied as plant-bound /sup 109/Cd or added to nonradioactive diets as /sup 109/CdCl/sup 2/. The mean retention of Cd in liver and kidney was 0.17% of the dose consumed for males and 0.26% for females consuming diets containing wheat, soybean, carrots, lettuce, or tomatoes.

Buhler, D.R.; Tinsley, I.J.

1987-07-01

369

An Image Segmentation Based on a Genetic Algorithm for Determining Soil Coverage by Crop Residues  

PubMed Central

Determination of the soil coverage by crop residues after ploughing is a fundamental element of Conservation Agriculture. This paper presents the application of genetic algorithms employed during the fine tuning of the segmentation process of a digital image with the aim of automatically quantifying the residue coverage. In other words, the objective is to achieve a segmentation that would permit the discrimination of the texture of the residue so that the output of the segmentation process is a binary image in which residue zones are isolated from the rest. The RGB images used come from a sample of images in which sections of terrain were photographed with a conventional camera positioned in zenith orientation atop a tripod. The images were taken outdoors under uncontrolled lighting conditions. Up to 92% similarity was achieved between the images obtained by the segmentation process proposed in this paper and the templates made by an elaborate manual tracing process. In addition to the proposed segmentation procedure and the fine tuning procedure that was developed, a global quantification of the soil coverage by residues for the sampled area was achieved that differed by only 0.85% from the quantification obtained using template images. Moreover, the proposed method does not depend on the type of residue present in the image. The study was conducted at the experimental farm “El Encín” in Alcalá de Henares (Madrid, Spain).

Ribeiro, Angela; Ranz, Juan; Burgos-Artizzu, Xavier P.; Pajares, Gonzalo; Sanchez del Arco, Maria J.; Navarrete, Luis

2011-01-01

370

Short-term cover crop decomposition in organic and conventional soils: Characterization of soil C, N, microbial and plant pathogen dynamics  

Microsoft Academic Search

Stages of oat-vetch cover crop decomposition were characterized over\\u000a time in terms of carbon and nitrogen cycling, microbial activity and\\u000a damping-off pathogen dynamics in organically and conventionally managed\\u000a soils in a field and a controlled incubation experiment. A measurement\\u000a of relative growth consisting of radial growth of a fungal colony over\\u000a non-sterilized soil divided by that over sterilized soil was

NJ Grunwald; S. Hu; A. H. C. van Bruggen

2000-01-01

371

Effects of Irrigating with Treated Oil and Gas Product Water on Crop Biomass and Soil Permeability  

SciTech Connect

Demonstrating effective treatment technologies and beneficial uses for oil and gas produced water is essential for producers who must meet environmental standards and deal with high costs associated with produced water management. Proven, effective produced-water treatment technologies coupled with comprehensive data regarding blending ratios for productive long-term irrigation will improve the state-of-knowledge surrounding produced-water management. Effective produced-water management scenarios such as cost-effective treatment and irrigation will discourage discharge practices that result in legal battles between stakeholder entities. The goal of this work is to determine the optimal blending ratio required for irrigating crops with CBNG and conventional oil and gas produced water treated by ion exchange (IX), reverse osmosis (RO), or electro-dialysis reversal (EDR) in order to maintain the long term physical integrity of soils and to achieve normal crop production. The soils treated with CBNG produced water were characterized with significantly lower SAR values compared to those impacted with conventional oil and gas produced water. The CBNG produced water treated with RO at the 100% treatment level was significantly different from the untreated produced water, while the 25%, 50% and 75% water treatment levels were not significantly different from the untreated water. Conventional oil and gas produced water treated with EDR and RO showed comparable SAR results for the water treatment technologies. There was no significant difference between the 100% treated produced water and the control (river water). The EDR water treatment resulted with differences at each level of treatment, which were similar to RO treated conventional oil and gas water. The 100% treated water had SAR values significantly lower than the 75% and 50% treatments, which were similar (not significantly different). The results of the greenhouse irrigation study found the differences in biomass production between each soil were significant for Western Wheatgrass and Alfafla. The Sheridan sandy loam soil resulted in the highest production for western wheatgrass and alfalfa while the X-ranch sandy loam had the lowest production rate for both plants. Plant production levels resulting from untreated CBNG produced water were significantly higher compared to untreated conventional oil and gas produced water. However, few differences were found between water treatments. The biomass produced from the greenhouse study was analyzed for elemental composition and for forage value. Elemental composition indentified several interesting findings. Some of the biomass was characterized with seemly high boron and sodium levels. High levels of boron found in some of the biomass was unexpected and may indicate that alfalfa and western wheatgrass plants may have been impacted by either soil or irrigation water containing high boron levels. Plants irrigated with water treated using EDR technology appeared to contain higher levels of boron with increased levels of treatment. Forage evaluations were conducted using near infrared reflectance spectroscopy. The data collected show small differences, generally less than 10%, between produced water treatments including the no treatment and 100% treatment conditions for each plant species studied. The forage value of alfalfa and western wheatgrass did not show significant tendencies dependent on soil, the amount of produced water treatment, or treatment technology.

Terry Brown; Jeffrey Morris; Patrick Richards; Joel Mason

2010-09-30

372

[Effect of land management in winter crop season on seasonal variations of CH4 emissions from rice paddy soils].  

PubMed

A pot experiment in greenhouse was carried out to study seasonal variations of CH4 fluxes from rice paddy soils and the effect of land management in winter crop season on the seasonal variations. The results showed that four emission peaks occurred respectively 13 days after flooding and 7, 40, 91 days after rice transplanting, and CH4 emission amounts during the first 30 days after flooding accounted for as high as 67.5%, 35.5% and 33.3% of the total emission amounts during the observing period of 133 days for treatments with dry fallow but rice straw being applied just before flooding, alfalfa, and flooded fallow in winter crop season. However, for treatments with dry fallow but rice straw being applied before winter crop cultivating and winter wheat in winter crop season, CH4 emission amounts during the first 50 days after flooding just accounted for 0.27% and 6.74 of the total emission amounts during the observing period, and CH4 fluxes thereafter were also very small. Difference in the seasonal variation patterns of soil Eh due to land management in winter crop season was the main reason why seasonal variation patterns of CH4 fluxes from different treatments were different. PMID:11767598

Xu, H; Cai, Z; Li, X; Tsuruta, H

2000-04-01

373

Effects of land use on annual runoff and soil loss -a meta-analysis of a European and Mediterranean plot database-  

NASA Astrophysics Data System (ADS)

Runoff and soil loss caused by water erosion are important desertification processes. While previous studies have shown the important effect of land use on annual soil loss (SLa), quantification of these effects based on field-measured data is limited and the effect of land use on annual runoff (Ra) and the relation between Ra and SLa has largely been neglected in the past. Nevertheless, runoff generation plays an equally important role as soil loss in desertification, especially in drier areas, where water is a key resource. Hence, sustainable land management practices to mitigate interrill and rill erosion should also consider the effects on runoff. Therefore, in the framework of the FP6 project DESIRE (http://www.desire-project.eu), the largest currently available database of plot runoff and soil loss data in Europe and the Mediterranean was compiled to investigate effects of land use on Ra, annual runoff coefficient (RCa) and SLa. This database comprises 227 plot-measuring sites in Europe and the Mediterranean, with SLa for 1061 plots (PL) representing 7 234 plot-years and Ra for 807 PL representing 5 357 plot-years. Bare soil, vineyards and tree crops were found to have high mean RCa (5-10 %) and mean SLa (10-20 Mg.ha-1.yr-1). Cropland and fallow show similar mean annual RCa (8.0 and 7.3 %), but lower SLa (6.5 and 5.8 Mg.ha-1.yr-1). Plots with (semi-)natural vegetation cover show the lowest mean annual RC (

Maetens, W.; Poesen, J.; Vanmaercke, M.

2012-04-01

374

Effect of soil pH on availability to crops of metals in sewage sludge-treated soils. II. Cadmium uptake by crops and implications for human dietary intake.  

PubMed

Appropriate pH-related permissible soil-limit concentrations for cadmium in sewage sludge-treated agricultural soils were estimated from the proportional changes in concentrations of cadmium in potatoes, oats and ryegrass grown on two sludge-amended soils and at different pH values. Implications for potential human dietary intake of cadmium were also assessed. Yields of crops increased with increasing soil pH, probably in response to decreasing uptake of zinc as soil pH value was raised. In general, cadmium concentrations in peeled potato tubers, potato peelings, oat straw and ryegrass decreased as simple linear functions of increasing soil pH over the range of pH values measured (pH 3.9-7.6). Cadmium concentrations in potato peel were particularly sensitive to changing pH conditions, whereas cadmium levels in oat grain were independent of soil pH. On the basis that a highly precautionary approach is adopted in setting soil standards for heavy metals, appropriate permissible concentrations of cadmium in sludge-treated agricultural soil which protect the human food chain were determined as 2.0 and 2.5 mg Cd Kg(-1) for banded pH ranges of 5.0-5.5 and 5.5-6.0, respectively. PMID:15091643

Smith, S R

1994-01-01

375

Effects of snow-cover on annual and seasonal soil respiration from a temperate mountain forest soil  

NASA Astrophysics Data System (ADS)

Climate change will alter the duration and magnitude of snow cover, especially in temperate areas at lower altitude, where wintertime air temperatures often fluctuate around freezing. A five years time series of consecutive soil respiration measurements was used to assess the effects of duration and magnitude of cold season snow-cover on annual and seasonal soil CO2 efflux. The temperature sensitivity of soil CO2 efflux during the cold season was assessed from seasonal data as well as from high frequency measurements during periods when air/soil temperatures showed high fluctuation. Substrate limitation as a potential driver of soil CO2 efflux during the cold season was tested by periodic amendment of sucrose followed by measurement and determination of the isotopic signature (13C) of the substrate induced soil respiration in the field. First results will be presented at the conference.

Schindlbacher, Andreas; Jandl, Robert; Schindlbacher, Sabine

2013-04-01

376

Assessment of crop growth and soil water modules in SWAT2000 using extensive field experiment data in an irrigation district of the Yellow River Basin  

USGS Publications Warehouse

SWAT, a physically-based, hydrological model simulates crop growth, soil water and groundwater movement, and transport of sediment and nutrients at both the process and watershed scales. While the different versions of SWAT have been widely used throughout the world for agricultural and water resources applications, little has been done to test the performance, variability, and transferability of the parameters in the crop growth, soil water, and groundwater modules in an integrated way with multiple sets of field experimental data at the process scale. Using an multiple years of field experimental data of winter wheat (Triticum aestivum L.) in the irrigation district of the Yellow River Basin, this paper assesses the performance of the plant-soil-groundwater modules and the variability and transferability of SWAT2000. Comparison of the simulated results by SWAT to the observations showed that SWAT performed quite unsatisfactorily in LAI predictions during the senescence stage, in yield predictions, and in soil-water estimation under dry soil-profile conditions. The unsatisfactory performance in LAI prediction might be attributed to over-simplified senescence modeling; in yield prediction to the improper computation of the harvest index; and in soil water under dry conditions to the exclusion of groundwater evaporation from the soil water balance in SWAT. In this paper, improvements in crop growth, soil water, and groundwater modules in SWAT were implemented. The saturated soil profile was coupled to the oscillating groundwater table. A variable evaporation coefficient taking into account soil water deficit index, groundwater depth, and crop root depth was used to replace the fixed coefficient in computing groundwater evaporation. The soil water balance included the groundwater evaporation. The modifications improved simulations of crop evapotranspiration and biomass as well as soil water dynamics under dry soil-profile conditions. The evaluation shows that the crop growth and soil water components of SWAT could be further refined to better simulate the hydrology of agricultural watersheds. ?? 2008 Elsevier B.V. All rights reserved.

Luo, Y.; He, C.; Sophocleous, M.; Yin, Z.; Hongrui, R.; Ouyang, Z.

2008-01-01

377

A review of the effects of tillage systems on some soil physical properties, water content, nitrate availability and crops yield in the Argentine Pampas  

Microsoft Academic Search

The Argentine Pampas is one of the most important cropping regions of the World. Limited tillage systems, and specially no-till, had widespread in recent years, occupying actually around 70% of the surface devoted to annual crops. We review results produced in field experiments installed along the Pampas to determine the effect of the adoption of these tillage systems on some

R. Alvarez; H. S. Steinbach

2009-01-01

378

Influence of soil organic matter on the sensitivity of selected wild and crop species to common herbicides.  

PubMed

Current regulatory protocols for assessing herbicide effects on plants rely heavily on the use of crops grown under controlled greenhouse conditions to indicate risks to wild vegetation. Guideline test protocols call for low levels of soil nutrients, approximately 3% organic matter (OM), to test the worst-case scenario for non-target species growing in poor soils. However, species sensitivity to herbicides may be affected by growing conditions, especially soil nutrient levels. The purpose of this study was to assess the impact of high and low soil OM content on the sensitivity of plants to several common agricultural herbicides (glyphosate, chlorimuron ethyl and dicamba). Ten plant species (wild and crop) with high (nitrophilous) or low (non-nitrophilous) affinity for nitrogen were grown under greenhouse conditions in soil with two levels of OM (3 and 9%) and were exposed to seven doses of the three herbicides in concurrent experiments. Results showed that most species were more sensitive to glyphosate under high OM conditions while chlorimuron ethyl and dicamba results were mixed with respect to OM levels. Overall, 15 species-herbicide combinations were more sensitive in high OM soil, while 11 were more sensitive in low OM soil. No clear pattern in sensitivity emerged among nitrophilous and non-nitrophilous species. Several species showed a difference in response at herbicide levels expected to reach non-target habitats adjacent to crop fields through drift (5% commonly and 25% occasionally). In terms of regulatory testing, guidelines may need alteration to allow testing with nutrient levels that more accurately reflect natural environments. PMID:23996626

Allison, Jane E; Boutin, Céline; Carpenter, David

2013-10-01

379

Relations between the metabolism of the insecticide carbofuran in the soil and in the plant of cauliflower and Brussels sprouts crops made in the field  

Microsoft Academic Search

The insecticide carbofuran was applied at planting onto soil around the stem of cauliflower and brussels sprouts plants of field crops made in different regions and seasons of culture. Carbofuran and its metabolites were measured several times in soil and plant growth. In the soil, carbofuran was metabolized into 3?ketocarbofuran, 3?hydroxycarbofuran, carbofuran phenol and 3?ketocarbofuran phenol. The rate of carbofuran

Jean Rouchaud; Fabrice Gustin; Frans van de Steene; Christian Pelerents; Frans Benoit; Norbert Ceustermans; Joel Gillet; Luc Vanparys

1989-01-01

380

Effects of soil sterilization, inoculation with vesicular-arbuscular mycorrhizal fungi and cropping history on peanut ( Arachis hypogaea L.) growth in an oxisol from subtropical Australia  

Microsoft Academic Search

The effects of soil sterilization and inoculation with vesicular-arbuscular mycorrhizal fungi (VAMF) on VAMF colonization, nutrition and growth of peanut plants (cv. Virginia Bunch) were investigated in an Oxisol soil in pots in the glasshouse. Sterilization, nutrient and inoculation treatments were applied to soil with a history of either continuous summer cropping (>50 years) or continuous grass pasture.

K. J. Middleton; M. J. Bell; J. P. Thompson

1989-01-01

381

Radium-226 transfer factor from soils to crops and its simple estimation method using uranium and barium concentrations.  

PubMed

Radium-226 ((226)Ra) should be assessed to determine the safety of geological disposal of high-level radioactive and transuranic wastes. Among the environmental transfer parameters that have been used in mathematical models for the environmental safety assessment, soil-to-plant transfer factor (F(v)) is of importance; it is defined as the plant/soil concentration ratio. Reported F(v) data for (226)Ra are still limited due to the low concentration of (226)Ra in plants in the natural environment. In this study, we collected F(v) of (226)Ra (F(v)-Ra) for crops and then applied a statistical approach to estimate F(v)-Ra instead of directly measuring the radionuclide. We found high correlations between (226)Ra and U concentrations in soils (because (226)Ra is a progeny in the (238)U series), and between (226)Ra and Ba concentrations in plants (because they are chemically similar in plant uptake). Using U in soil and Ba in plant values, we could estimate F(v)-Ra with good accuracy; the difference between estimated and measured F(v)-Ra values was a factor of 1.2 on average for crops. The method could estimate F(v)-Ra for the soil-to-plant systems where (226)Ra and Ba concentrations in soil are within the normal range, e.g. 8-100 Bq kg(-1)-dry for (226)Ra and 84-960 mg kg(-1)-dry for Ba. PMID:19501875

Tagami, Keiko; Uchida, Shigeo

2009-09-01

382

Fecal bacteria and sex hormones in soil and runoff from cropped watersheds amended with poultry litter.  

PubMed

The application of poultry litter to agricultural fields can provide plant nutrients for crops and forage production, but fecal bacteria and the sex hormones estradiol and testosterone are components of litter that can be detrimental to the environment. Our objective was to determine if applications of poultry litter to small watersheds would contribute to the load of fecal bacteria and sex hormones to soil and runoff. We, therefore, investigated the fate and transport of fecal bacteria, estradiol and testosterone from surface applied poultry litter to four small watersheds. Poultry litter was applied to meet the nitrogen requirements of pearl millet (Pennisetum glaucum L.) in 2000 and grain sorghum [Sorgham bicolor (L.) Moench] in 2001. Neither Salmonella nor Campylobacter were detected in the litter but the fecal indicator bacteria were. The average load of total coliforms,Escherichia coli, and fecal enterococci applied with the litter was 12.2, 11.9, and 12.7 log10 cells ha(?1), respectively. The average load of estradiol and testosterone was 3.1 and 0.09 mg ha(-1), respectively.Runoff events first occurred seven months after the first litter application in 2000, and three weeks after the second application in 2001.Only for the 25 July 2001 runoff event three weeks after the second litter application, were the concentrations of total coliforms, E. coli,and fecal enterococci in runoff greater than background concentrations which were on average 5.2, 1.1, and 2.9 log10 MPN 100 ml(?1),respectively [corrected]. Average background levels of total coliforms, fecal enterococci,and E. coli in surface soil were 8.2, 7.9, and 3.5 log (10) cells kg(?1) soil. At the rate of litter application the concentrations of estradiol and testosterone in the litter did not appear to impact the background levels in the soil and runoff. Because concentrations of sex hormones in litter from other broiler operations are known to be greater than in the litter we applied, further study on the connection between concentrations of sex hormones in poultry litter and operational practices is recommended. PMID:15927239

Jenkins, Michael B; Endale, Dinku M; Schomberg, Harry H; Sharpe, Ronald R

2006-04-01

383

High Phosphorus Soils: Management Issues in Eastern Canada  

Microsoft Academic Search

High P soils are an asset for crop production since farmers do not have to spend for additional P fertilizers to produce their annual crop. This is a challenge for farmers which have to manage manure on a limited land base. High P soils become a source of P, especially when they are near sensitive water bodies. Surface waters that

Régis R. Simard

384

Discriminating Crop, Weeds and Soil Surface with a Terrestrial LIDAR Sensor  

PubMed Central

In this study, the evaluation of the accuracy and performance of a light detection and ranging (LIDAR) sensor for vegetation using distance and reflection measurements aiming to detect and discriminate maize plants and weeds from soil surface was done. The study continues a previous work carried out in a maize field in Spain with a LIDAR sensor using exclusively one index, the height profile. The current system uses a combination of the two mentioned indexes. The experiment was carried out in a maize field at growth stage 12–14, at 16 different locations selected to represent the widest possible density of three weeds: Echinochloa crus-galli (L.) P.Beauv., Lamium purpureum L., Galium aparine L.and Veronica persica Poir.. A terrestrial LIDAR sensor was mounted on a tripod pointing to the inter-row area, with its horizontal axis and the field of view pointing vertically downwards to the ground, scanning a vertical plane with the potential presence of vegetation. Immediately after the LIDAR data acquisition (distances and reflection measurements), actual heights of plants were estimated using an appropriate methodology. For that purpose, digital images were taken of each sampled area. Data showed a high correlation between LIDAR measured height and actual plant heights (R2 = 0.75). Binary logistic regression between weed presence/absence and the sensor readings (LIDAR height and reflection values) was used to validate the accuracy of the sensor. This permitted the discrimination of vegetation from the ground with an accuracy of up to 95%. In addition, a Canonical Discrimination Analysis (CDA) was able to discriminate mostly between soil and vegetation and, to a far lesser extent, between crop and weeds. The studied methodology arises as a good system for weed detection, which in combination with other principles, such as vision-based technologies, could improve the efficiency and accuracy of herbicide spraying.

Andujar, Dionisio; Rueda-Ayala, Victor; Moreno, Hugo; Rosell-Polo, Joan Ramon; Escola, Alexandre; Valero, Constantino; Gerhards, Roland; Fernandez-Quintanilla, Cesar; Dorado, Jose; Griepentrog, Hans-Werner

2013-01-01

385

Effects of Acidic Deposition on Agricultural Crops: Task D. Annual Report.  

National Technical Information Service (NTIS)

The objectives of this experiment were to determine the effects of the acidity of simulated precipitation on soybean growth and yield, and to determine the effects of ambient rain exclusion on field crop response to simulated acid rain. Increasing the aci...

D. T. DuBay A. S. Heagle

1983-01-01

386

Growth Suppression of Annual Weeds by Deleterious Rhizobacteria Integrated with Cover Crops  

Microsoft Academic Search

Development and rapid acceptance of biological control is challenged by factors lim- iting the spectrum of activity, efficacy, and reliability. Effectiveness of biological control may be best demonstrated as a component in an overall biological weed management sys- tem. Cover crops as components of biological weed management may be used for inte- grating biological control agents by promoting establishment in

R. J. KREMER

387

Phytoavailability and fractionation of copper, manganese, and zinc in soil following application of two composts to four crops.  

PubMed

Two experiments were conducted to evaluate the effect of compost addition to soil on fractionation and bioavailability of Cu, Mn, and Zn to four crops. Soils growing Swiss chard (Beta vulgaris var. cicla L.) and basil (Ocimum basilicum L.) were amended (by volume) with 0, 20, 40, and 60% Source-Separated Municipal Solid Waste (SS-MSW) compost, and dill (Anethum graveolens L.) and peppermint (Mentha X piperita L.) were amended with 0, 20, 40, and 60% of high-Cu manure compost (by volume). The SS-MSW compost applications increased the concentration of Cu and Zn in all fractions, increased Mn in acid extractable (ACID), iron and manganese oxides (FeMnOX), and organic matter (OM) fractions, but decreased slightly exchangeable-Mn. Addition of 60% high-Cu manure compost to the soil increased Cu EXCH, ACID, FeMnOX, and OM fractions, but decreased EXCH-Mn, and did not change EXCH-Zn. Addition of both composts to soil reduced bioavailability and transfer factors for Cu and Zn. Our results suggest that mature SS-MSW and manure composts with excess Cu and Zn could be safely used as soil conditioners for agricultural crops. PMID:15234085

Zheljazkov, Valtcho D; Warman, Phil R

2004-09-01

388

Soil organic carbon (SOC) management for sustainable productivity of cropping and agro-forestry systems in Eastern and Southern Africa  

Microsoft Academic Search

In Eastern and Southern Africa, the shifting from the no-external input agriculture (shifting cultivation through slash and\\u000a burn) to intensified agricultural systems has resulted in widespread agro-ecosystems with high soil organic carbon and nutrient\\u000a depletion. This is quite evident in farming systems with reduced fallow period or those that practice continuous cropping\\u000a without or with little inputs. Long-term experiments indicate

Stephen M. Nandwa

2001-01-01

389

Prospects of Arbuscular Mycorrhiza in Sustainable Management of Root and Soil-Borne Diseases of Vegetable Crops  

Microsoft Academic Search

Vegetable crops are highly prone to a number of root and soil borne diseases causing great losses in yield and quality. Indiscriminate\\u000a use of fungicides and pesticides in controlling the diseases has polluted the environment and produce. Thus, there is need\\u000a of proper management of these diseases at reduced doses of pesticides to sustain the vegetable production. Biological control\\u000a of

M. Sharma; A. Gaur; Tanu; O. Sharma

390

Effect of rotation, nitrogen fertilization and management of crop residues on some chemical, microbiological and biochemical properties of soil  

Microsoft Academic Search

A long-term experiment, which started in 1971 near Perugia, central Italy, was performed to investigate the effect of different\\u000a crop residue management practices and rotation systems on some soil properties. Twenty years after the beginning of the experiment,\\u000a chemical (organic C, total N, humified organic C, humic and fulvic acids), microbiological and biochemical parameters (microbial\\u000a biomass, global hydrolase activity, dehydrogenase

P. Perucci; U. Bonciarelli; R. Santilocchi; A. A. Bianchi

1997-01-01

391

Effects of summer cover crop and residue management on cucumber growth in intensive Chinese production systems: soil nutrients, microbial properties and nematodes  

Microsoft Academic Search

Yield increases of cucumber following cover crops in a rotation system have been previously reported for intensive Chinese\\u000a agricultural production. However, little information is available as to how this system affects soil microbial properties\\u000a and nematodes. A 4-year field experiment on a greenhouse cucumber double-cropping system was conducted to investigate the\\u000a effects of four different summer cover crops on cucumber

Yongqiang Tian; Xueyan Zhang; Jun Liu; Lihong Gao

2011-01-01

392

Effect of conjoint use of bio-organics and chemical fertilizers on yield, soil properties under French bean–cauliflower-based cropping system  

Microsoft Academic Search

This study investigates the effect of conjoint use of bio-organics (biofertilizers + crop residues + FYM) and chemical fertilizers on yield, physical–chemical and microbial properties of soil in a ‘French bean–cauliflower’-based cropping system of mid hills of the north-western Himalayan Region (NWHR) of India. Conjoint bio-organics at varied levels of NPK chemical fertilizers increased yield of ‘cauliflower’ over corresponding single application. Incorporation of crop

Satish Kumar Bhardwaj; Som Dev Sharma; Pramod Kumar

2012-01-01

393

Effect of conjoint use of bio-organics and chemical fertilizers on yield, soil properties under French bean–cauliflower-based cropping system  

Microsoft Academic Search

This study investigates the effect of conjoint use of bio-organics (biofertilizers + crop residues + FYM) and chemical fertilizers on yield, physical–chemical and microbial properties of soil in a ‘French bean–cauliflower’-based cropping system of mid hills of the north-western Himalayan Region (NWHR) of India. Conjoint bio-organics at varied levels of NPK chemical fertilizers increased yield of ‘cauliflower’ over corresponding single application. Incorporation of crop

Satish Kumar Bhardwaj; Som Dev Sharma; Pramod Kumar

2011-01-01

394

Effect of Incorporation of Crop Residues on a Maize–Groundnut Sequence in the Humid Tropics. II. Soil Physical and Chemical Properties  

Microsoft Academic Search

A two?year study (1997–1999) was conducted on a sandy clay loam (Typic Paleudult) at the experimental farm of the Universiti Putra to determine the effects of application of crop residues on changes of some soil properties in a maize (Zea mays L.)–groundnut (Arachis hypogaea) crop rotation system. Five crops of a rotation of sweet corn–groundnut–sweet corn–groundnut–sweet corn were sown with

A. R. Mubarak; A. B. Rosenani; A. R. Anuar; D. Siti Zauyah

2003-01-01

395

Long-term tillage and maize monoculture effects on a tropical Alfisol in western Nigeria. I. Crop yield and soil physical properties  

Microsoft Academic Search

A wide range of tillage methods (e.g. mouldboard ploughing, discing, harrowing, chiselling, notill, ridge till, and their combinations) are used for continuous maize (Zea mays L.) cropping in western Nigeria without the benefits of experimental data on their comparative effects on soil properties and crop response. Therefore, the main objective of this experiment was to evaluate the impact of a

R. Lal

1997-01-01

396

Soil salinity: Irrigation practices and effects on crops and ground water. (Latest citations from the Selected Water Resources Abstracts database). Published Search  

SciTech Connect

The bibliography contains citations concerning the effect of saline irrigation waters on crops and groundwater. The salt tolerance of crops, including beans, grains, and citrus fruits, is examined. The salinity of soils, groundwater, and surface water is discussed, and the sources of brackish waters are considered. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1993-03-01

397

[Effects of rape cropping in summer fallow period on dryland soil moisture content and winter wheat yield].  

PubMed

Taking the fallow land with wheat stubble after harvesting as the control, a 4-year field experiment was conducted in a dryland of east Gansu, Northwest China to investigate the effects of rape cropping in summer fallow period on the soil moisture content, wheat yield, and water use efficiency (WUE). The rape was sown at 6 dates. There was a significant difference (P < 0.05) in the soil moisture content in summer fallow period when the rape was sown at different dates. When the rape was sown on August 5, the soil water storage efficiency was 58.5%, and the wheat yield and WUE were increased by 7.5% and 5.9%, respectively, as compared with the control. Averagely, cropping rape in fallow period could increase the wheat yield by 16. 1% in dry year and 6.8% in normal year. It was suggested that rape cropping in summer fallow period would benefit the wheat yield and drought resistance of drylands in Northwest China. PMID:24483074

Zhao, Gang; Fan, Ting-Lu; Li, Shang-Zhong; Zhang, Jian-Jun; Wang, Yong; Dang, Yi; Wang, Lei

2013-10-01

398

Use of Green Manure\\/Cover Crops and Conservation Tillage in Santa Catarina, Brazil  

Microsoft Academic Search

The shallow, heavy soils, hilly topography and high rainfall of Santa Catarina contribute to intense erosion when management\\u000a of soil cover is inadequate. Increasingly, hillside farmers practicing annual cropping leave plant residues on the soil surface\\u000a to minimize erosion and to reduce fluctuations of soil water and temperature. Over time, repeated additions of fresh, high-quality\\u000a green manures to the soil

L. Prado Wildner; V. Hercilio Freitas; M. McGuire

399

Plant-soil interactions in multistrata agroforestry in the humid tropics  

Microsoft Academic Search

Multistrata agroforestry systems with tree crops comprise a variety of land use systems ranging from plantations of coffee, cacao or tea with shade trees to highly diversified homegardens and multi-storey tree gardens. Research on plant-soil interactions has concentrated on the former. Tree crop-based land use systems are more efficient in maintaining soil fertility than annual cropping systems. Certain tree crop

G. Schroth; J. Lehmann; M. R. L. Rodrigues; E. Barros; J. L. V. Macêdo

2001-01-01

400

Plant-soil interactions in multistrata agroforestry in the humid tropicsa  

Microsoft Academic Search

Multistrata agroforestry systems with tree crops comprise a variety of land use systems ranging from plantations of coffee,\\u000a cacao or tea with shade trees to highly diversified homegardens and multi-storey tree gardens. Research on plant-soil interactions\\u000a has concentrated on the former. Tree crop-based land use systems are more efficient in maintaining soil fertility than annual\\u000a cropping systems. Certain tree crop

G. Schroth; J. Lehmann; M. R. L. Rodrigues; E. Barros; J. L. V. Macêdo

2001-01-01