Science.gov

Sample records for agricultural field site

  1. Effects of topography and soil properties on recharge at two sites in an agricultural field

    USGS Publications Warehouse

    Delin, G.N.; Healy, R.W.; Landon, M.K.; Böhlke, J.K.

    2000-01-01

    Field experiments were conducted from 1992 to 1995 to estimate ground water recharge rates at two sites located within a 2.7-hectare agricultural field. The field lies in a sand plain setting in central Minnesota and is cropped continuously in field corn. The sites are located at a topographically high (upland) site and a topographically low (lowland) site in an effort to quantify the effects of depression focusing of recharge. Three site-specific methods were used to estimate recharge rates: well hydrograph analysis, chlorofluorocarbon age dating, and an unsaturated zone water balance. All three recharge methods indicated that recharge rates at the lowland site (annual average of all methods of 29 cm) exceeded those at the upland site (annual average of 18 cm). On an annual basis, estimates by the individual methods ranged from 12 to 44 percent of precipitation at the upland site and from 21 to 83 percent at the lowland site. The difference in recharge rates between the sites is primarily attributed to depression focusing of surface water runon at the lowland site. However, two other factors were also important: the presence of thin lamellae at the upland site, and coarser textured soils below a depth of 1.5 m at the lowland site.

  2. Agricultural Aircraft for Site-Specific Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural aircraft provide a convenient platform to aid in precision agriculture, in which pesticide, fertilizer or other field inputs are applied only where they are needed. This saves on chemical and farm resources, and reduces environmental loading. Remote sensing is used to spot areas of the ...

  3. Modelling field scale water partitioning using on-site observations in sub-Saharan rainfed agriculture

    NASA Astrophysics Data System (ADS)

    Makurira, H.; Savenije, H. H. G.; Uhlenbrook, S.

    2009-08-01

    Smallholder rainfed farming systems generally realise sub-optimal crop yields which are largely attributed to dry spell occurrences during crop growth stages. However, with improved farming practices, it seems possible to significantly increase yield levels even with little and highly variable rainfall. The presented results follow research conducted in the Makanya catchment in northern Tanzania where gross rainfall amounts to less than 400 mm/season which is insufficient to support staple food crops (e.g. maize). Alternative cultivation techniques such as runoff harvesting and in-field micro-storage structures are compared. These techniques aim to reduce soil and nutrient loss from the field but, more importantly, promote in-field infiltration and water retention. Water balance components have been observed in order to study water partitioning processes under different cultivation techniques. Based on rainfall, soil evaporation, transpiration, runoff and soil moisture measurements, a water balance model has been developed to simulate soil moisture variations over the growing season. It appears that about 50% of the diverted water leaves the root zone through deep percolation. Modelling shows that during the field trials the average productive transpiration flow ranged between 1.1-1.4 mm d-1 in the trial plots compared to 0.7-1.0 mm d-1 under traditional tillage practice. Productive transpiration processes accounted for 23-29% while losses to deep percolation accounted for 33-48% of the available water. Conclusions from the research are that the innovations tested are effective in enhancing soil moisture retention at field scale and that diversions allow crop growth moisture conditions to be attained with early rains. It is also concluded that there is more scope for efficient utilisation of the diverted runoff water if storage structures could be installed to regulate water flow to the root zone when required.

  4. Modelling field scale water partitioning using on-site observations in sub-Saharan rainfed agriculture

    NASA Astrophysics Data System (ADS)

    Makurira, H.; Savenije, H. H. G.; Uhlenbrook, S.

    2010-04-01

    Smallholder rainfed farming systems generally realise sub-optimal crop yields which are largely attributed to dry spell occurrences during crop growth stages. However, through the introduction of appropriate farming practices, it is possible to substantially increase yield levels even with little and highly variable rainfall. The presented results follow research conducted in the Makanya catchment in northern Tanzania where gross rainfall amounts to less than 400 mm/season which is insufficient to support staple food crops (e.g. maize). The yields from farming system innovations (SIs), which are basically alternative cultivation techniques, are compared against traditional farming practices. The SIs tested in this research are runoff harvesting used in combination with in-field trenches and soil bunds (fanya juus). These SIs aim to reduce soil and nutrient loss from the field and, more importantly, promote in-field infiltration and water retention. Water balance components have been observed in order to study water partitioning processes for the "with" and "without" SI scenarios. Based on rainfall, soil evaporation, transpiration, runoff and soil moisture measurements, a water balance model has been developed to simulate soil moisture variations over the growing season. Simulation results show that, during the field trials, the average productive transpiration flow ranged between 1.1-1.4 mm d-1 in the trial plots compared to 0.7-1.0 mm d-1 under traditional tillage practice. Productive transpiration processes accounted for 23-29% while losses to deep percolation accounted for 33-48% of the available water. The field system has been successfully modelled using the spreadsheet-based water balance 1-D model. Conclusions from the research are that the SIs that were tested are effective in enhancing soil moisture retention at field scale and that diversions allow crop growth moisture conditions to be attained with early rains. From the partitioning analysis, it is also

  5. Understanding the ecological background of rice agriculture on the Ningshao Plain during the Neolithic Age: pollen evidence from a buried paddy field at the Tianluoshan cultural site

    NASA Astrophysics Data System (ADS)

    Li, Chunhai; Zheng, Yunfei; Yu, Shiyong; Li, Yongxiang; Shen, Huadong

    2012-03-01

    The progressive rise of atmospheric CH4 level since 5 ka has been hypothesized to result from human agricultural activities that turned forested lands, which would otherwise be a carbon sink, into paddy fields. Increasing numbers of Neolithic cultural sites unearthed in coastal eastern China, providing unique opportunities to test this hypothesis. Here, we present detailed pollen data from a buried paddy field at Tianluoshan cultural site on the Ningshao Plain, eastern China, to reconstruct the ecological conditions associated with the establishment of paddy fields. Stratigraphic data, radiocarbon ages, and pollen analyses show that vegetation underwent six phases of evolution and paddy fields were developed from 7000 to 4200 cal. yr BP. We found no evidence of slash-and-burn agriculture at the study site. Together with no presence of the irrigation system, our pollen data suggest the paddy fields at this site originated from wetlands. Hence, our findings do not support the hypothesis that anthropogenic-induced deforestation play ed a significant role in the rise of the atmospheric CH4 rise since the middle Holocene.

  6. Application of ERTS-1 imagery in the fields of geology, agriculture, forestry, and hydrology to selected test sites in Iran

    NASA Technical Reports Server (NTRS)

    Ebtehadj, K.

    1973-01-01

    The preliminary study of the ERTS-1 imagery coverage of Iran, commenced on October 26, 1972. All of the images were carefully examined, and a photomosaic covering approximately ninety-five per cent of the country was prepared. A number of images of selected areas were studied in detail. In the field of geology, a number of large scale faults were identified, which do not figure on geological maps. Furthermore, a preliminary study was carried out on the recent sediments, their possible sources, and origin. A limited number of geological work maps were prepared as well. In the fields of agriculture and forestry, studies based on color composite prints of certain areas were undertaken, with a purpose of identifying potential arable areas. Investigations in the field of water resources resulted in the discovery of a number of small lakes, and streams. Furthermore, fluctuations of the water level in some lakes were observed.

  7. Agricultural fields, Khartoum, Sudan, Africa

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This herringbone pattern of irrigated agricultural fields near Khartoum, Sudan (14.5N, 33.5E) is very distinctive in both size and shape. The region contains thousands of these rectangular fields bounded by canals which carry water from both the White and Blue Nile Rivers. A crop rotation system is used so that some fields are in cotton, millit, sorghum or fallow to conserve moisture and control weeds and insects. See also STS049-96-003.

  8. Field spectroscopy of agricultural crops

    NASA Technical Reports Server (NTRS)

    Bauer, M. E.; Daughtry, C. S. T.; Biehl, L. L.; Kanemasu, E. T.; Hall, F. G.

    1986-01-01

    The development of the full potential of multispectral data acquired from satellites, requires quantitative knowledge, and physical models of the spectral properties of specific earth surface features. Knowledge of the relationships between spectral-radiometric characteristics and important biophysical parameters of agricultural crops and soils can best be obtained by carefully controlled studies of fields or plots. It is important to select plots where data describing the agronomic-biophysical properties of the crop canopies and soil background are attainable, taking into account also the feasibility of frequent timely calibrated spectral measurements. The term 'field spectroscopy' is employed for this research. The present paper is concerned with field research which was sponsored by NASA as part of the AgRISTARS Supporting Research Project. Attention is given to field research objectives, field research instrumentation, measurement procedures, spectral-temporal profile modeling, and the effects of cultural and environmental factors on crop reflectance.

  9. Field site selection

    NASA Technical Reports Server (NTRS)

    Schwarz, D. E.; Ellefsen, R. E.

    1981-01-01

    Several general guidelines should be kept in mind when considering the selection of field sites for teaching remote sensing fundamentals. Proximity and vantage point are two very practical considerations. Only through viewing a broad enough area to place the site in context can one make efficient use of a site. The effects of inclement weather when selecting sites should be considered. If field work is to be an effective tool to illustrate remote sensing principles, the following criteria are critical: (1) the site must represent the range of class interest; (2) the site must have a theme or add something no other site offers; (3) there should be intrasite variation within the theme; (4) ground resolution and spectral signature distinction should be illustrated; and (5) the sites should not be ordered sequentially.

  10. AmeriFlux US-IB1 Fermi National Accelerator Laboratory- Batavia (Agricultural site)

    SciTech Connect

    Matamala, Roser

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-IB1 Fermi National Accelerator Laboratory- Batavia (Agricultural site). Site Description - Two eddy correlation systems are installed at Fermi National Accelerator Laboratory: one on a restored prairie (established October 2004) and one on a corn/soybean rotation agricultural field (established in July 2005). The prairie site had been farmed for more than 100 years, but was converted to prairie in 1989. The agricultural site has likely been farmed for more than 100 years, but the first documented instance of agricultural activity dates back to a picture taken in 1952.

  11. Site Description for the University of Nebraska's Sandhills Agricultural Laboratory

    NASA Technical Reports Server (NTRS)

    Gardner, B. R.; Blad, B. L.

    1985-01-01

    The Sandhills Agricultural Laboratory is operated by the University of Nebraska. The laboratory is located in the south-central part of the Nebraska Sandhills near Tryon, Nebraska (41 deg. 37' N; 100 deg. 50' W). The laboratory is surrounded on the west and south by native rangeland vegetation, on the south by a large field of corn irrigated by a center pivot, and on the east by wheat stubble. This site is appropriate for moisture stress studies since rainfall is almost always inadequate to meet evaporative demands of agricultural crops during most of the growing season and the sandy soils (Valentine fine sand) at the site do not store large quantities of water. Various levels of water stress are achieved through irrigation from solid set sprinklers.

  12. 7 CFR 3434.5 - Agriculture-related fields.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Agriculture-related fields. 3434.5 Section 3434.5 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HISPANIC-SERVING AGRICULTURAL COLLEGES AND UNIVERSITIES CERTIFICATION PROCESS § 3434.5...

  13. 7 CFR 3434.5 - Agriculture-related fields.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Agriculture-related fields. 3434.5 Section 3434.5 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HISPANIC-SERVING AGRICULTURAL COLLEGES AND UNIVERSITIES CERTIFICATION PROCESS § 3434.5...

  14. Site specific irrigation management-Precision agriculture for improved water use efficiency

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision agriculture involves aspects of sensing, crop protection, field sampling, precision tillage and planting, fertilizer application, pest control, irrigation, on-the-go yield monitoring and other emerging applications. Site specific irrigation management (SSIM) focuses on the delivery of app...

  15. Estimation of the degree of soil P saturation from Brazilian Mehlich-1 P data and field investigations on P losses from agricultural sites in Minas Gerais.

    PubMed

    Fischer, P; Pöthig, R; Gücker, B; Venohr, M

    2016-01-01

    The degree of phosphorus saturation (DPS) of agricultural soils is studied worldwide for risk assessment of phosphorus (P) losses. In previous studies, DPS could be reliably estimated from water-soluble P (WSP) for European and Brazilian soils. In the present study, we correlated measured WSP and Mehlich-1 P (M1P) from soils of Minas Gerais (MG) and Pernambuco (PE) (R(2) = 0.94, n = 59) to create a DPS map from monitoring data. The resulting DPS map showed high spatial variability and low values of DPS (54 ± 22%, mean and standard deviation; n = 1,827). Measured soil DPS values amounted to 63 ± 14% and resulted in relatively low dissolved P concentrations measured in a surface runoff study in MG. However, fertilizer grains on the soil surface led to high WSP values (>30 mg/kg) indicating high risks of dissolved P losses. We suppose that small Oxisol particles with Fe and Al hydroxides sorbed most of the dissolved fertilizer P in runoff so that P was mainly exported in particulate form. In soils with lower contents of P sorption and binding partners, e.g. Entisols in PE, this effect may be less dominant. Consequently, superficial fertilizer effects have to be considered in addition to DPS in risk assessment of P losses from agricultural areas in Brazil. PMID:27508374

  16. Distribution and persistence of tricyaclazole in agricultural field soils.

    PubMed

    Jeong, Seul Ah; Thapa, Shree Prasad; Park, Hong Ryeol; Choi, Nam Geon; Hur, Jang Hyun

    2012-12-01

    Soil is the major sink for majority of pesticides applied on agricultural crops and its fate depends on variety of factors. There is little research on fate of pesticide in field soil under different climatic conditions and there is a need of study on the influence of climate on pesticide degradation and persistence in soil. In the present study, the persistence and distribution of tricyclazole was investigated in rice field soil under the influence of cold winter condition. Field experiment was carried at 35 different field sites from 6 provinces in Republic of Korea. Limit of detection and limit of quantification of tricyclazole were found to be 0.005 and 0.0165 mg/kg, respectively. The concentrations of tricyclazole in soil samples ranged from 0.387 mg/kg in sites in Gyeongsangbuk-do areas and lowest 0.021 mg/kg in sites from Chuncheongnam-do areas. In natural environmental conditions, tricyclazole persisted longer than 11 months post application in agricultural field soils. Our result indicates the influence of cold climatic condition on the persistence of tricyclazole. PMID:23014634

  17. Tension on the Farm Fields: The Death of Traditional Agriculture?

    ERIC Educational Resources Information Center

    Oguamanam, Chidi

    2007-01-01

    Taking into account the historic transitions and progressions in agricultural science, this article examines the emergence of the phenomenon of agricultural biotechnology. It identifies pivotal sites of tension between agricultural biotechnology and alternative approaches to agriculture. The article identifies two distinct sources of contemporary…

  18. Methane uptake in agricultural and old-field ecosystems

    SciTech Connect

    Reed, W.L.; Halstead, S.J.; Robertson, G.P. Michigan State Univ., East Lansing )

    1993-06-01

    Atmospheric methane (CH[sub 4]) concentrations are rising approximately 1% per year, with important consequences for the earth's radiation balance and tropospheric chemistry. Sources of this increase are not well known; recent evidence suggests that land conversion to agriculture may play some role in this increase if CH[sub 4] consumption in upland soils is suppressed by agronomic activities. We tested this hypothesis in a series of replicated agricultural and old-field communities at the KBS LTER site in southwest Michigan. We measured CH[sub 4] flux with static chambers in 6 different cropping systems (conventional till and no-till annual crops, ridge-till organic based crops, perennial crops) and in early successional and mid-succession (never tilled) old field communities. Chambers were sampled 17 times over the 1992 growing season and analyzed for CH[sub 4], N[sub 2]O, and CO[sub 2]. We found significant but highly variable CH[sub 4] uptake on some dates in all 8 ecosystem types, with most consistent consumption in the organic based crops and old-field communities.

  19. Zoning of agricultural field using a fuzzy indicators model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zoning of agricultural fields is an important task for utilization of precision farming technology. One method for deciding how to subdivide a field into a few relatively homogenous zones is using applications of fuzzy sets theory. Data collected from a precision agriculture study in central Texas...

  20. Classification and soil moisture determination of agricultural fields

    NASA Technical Reports Server (NTRS)

    Vandenbroek, A. C.; Groot, J. S.

    1993-01-01

    During the Mac-Europe campaign of 1991 several SAR (Synthetic Aperature Radar) experiments were carried out in the Flevoland test area in the Netherlands. The test site consists of a forested and an agricultural area with more than 15 different crop types. The experiments took place in June and July (mid to late growing season). The area was monitored by the spaceborne C-band VV polarized ERS-1, the Dutch airborne PHARS with similar frequency and polarization and the three-frequency PP-, L-, and C-band) polarimetric AIRSAR system of NASA/JPL. The last system passed over on June 15, 3, 12, and 28. The last two dates coincided with the overpasses of the PHARS and the ERS-1. Comparison of the results showed that backscattering coefficients from the three systems agree quite well. In this paper we present the results of a study of crop type classification (section 2) and soil moisture determination in the agricultural area (section 3). For these studies we used field averaged Stokes matrices extracted from the AIRSAR data (processor version 3.55 or 3.56).

  1. Fungal biology and agriculture: revisiting the field

    USGS Publications Warehouse

    Yarden, O.; Ebbole, D.J.; Freeman, S.; Rodriguez, R.J.; Dickman, M. B.

    2003-01-01

    Plant pathology has made significant progress over the years, a process that involved overcoming a variety of conceptual and technological hurdles. Descriptive mycology and the advent of chemical plant-disease management have been followed by biochemical and physiological studies of fungi and their hosts. The later establishment of biochemical genetics along with the introduction of DNA-mediated transformation have set the stage for dissection of gene function and advances in our understanding of fungal cell biology and plant-fungus interactions. Currently, with the advent of high-throughput technologies, we have the capacity to acquire vast data sets that have direct relevance to the numerous subdisciplines within fungal biology and pathology. These data provide unique opportunities for basic research and for engineering solutions to important agricultural problems. However, we also are faced with the challenge of data organization and mining to analyze the relationships between fungal and plant genomes and to elucidate the physiological function of pertinent DNA sequences. We present our perspective of fungal biology and agriculture, including administrative and political challenges to plant protection research.

  2. AmeriFlux US-Br1 Brooks Field Site 10- Ames

    DOE Data Explorer

    Parkin, Tim [USDA; Prueger, John [National Laboratory for Agriculture and the Environment

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Br1 Brooks Field Site 10- Ames. Site Description - The Brooks Field Site 10 - Ames Site is one of three sites (Brooks Field Site 11 and Brooks Field Site 1011) located in a corn/soybean agricultural landscape of central Iowa. The farming systems, associated tillage, and nutrient management practices for soybean/corn production are typical of those throughout Upper Midwest Corn Belt. All three sites are members of the AmeriFlux network. Information for all three can be found in synchronous pages of this website.

  3. AmeriFlux US-Br3 Brooks Field Site 11- Ames

    DOE Data Explorer

    Parkin, Tim [USDA; Prueger, John [National Laboratory for Agriculture and the Environment

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Br3 Brooks Field Site 11- Ames. Site Description - The Brooks Field Site 11 - Ames Site is one of three sites (Brooks Field Site 10 and Brooks Field Site 1011) located in a corn/soybean agricultural landscape of central Iowa. The farming systems, associated tillage, and nutrient management practices for soybean/corn production are typical of those throughout Upper Midwest Corn Belt. All three sites are members of the AmeriFlux network. Information for all three can be found in synchronous pages of this website.

  4. About soil cover heterogeneity of agricultural research stations' experimental fields

    NASA Astrophysics Data System (ADS)

    Rannik, Kaire; Kõlli, Raimo; Kukk, Liia

    2013-04-01

    Depending on local pedo-ecological conditions (topography, (geo) diversity of soil parent material, meteorological conditions) the patterns of soil cover and plant cover determined by soils are very diverse. Formed in the course of soil-plant mutual relationship, the natural ecosystems are always influenced to certain extent by the other local soil forming conditions or they are site specific. The agricultural land use or the formation of agro-ecosystems depends foremost on the suitability of soils for the cultivation of feed and food crops. As a rule, the most fertile or the best soils of the area, which do not present any or present as little as possible constraints for agricultural land use, are selected for this purpose. Compared with conventional field soils, the requirements for the experimental fields' soil cover quality are much higher. Experimental area soils and soil cover composition should correspond to local pedo-ecological conditions and, in addition to that, represent the soil types dominating in the region, whereas the fields should be as homogeneous as possible. The soil cover heterogeneity of seven arable land blocks of three research stations (Jõgeva, Kuusiku and Olustvere) was studied 1) by examining the large scale (1:10 000) digital soil map (available via the internet), and 2) by field researches using the transect method. The stages of soils litho-genetic and moisture heterogeneities were estimated by using the Estonian normal soils matrix, however, the heterogeneity of top- and subsoil texture by using the soil texture matrix. The quality and variability of experimental fields' soils humus status, was studied more thoroughly from the aspect of humus concentration (g kg-1), humus cover thickness (cm) and humus stocks (Mg ha-1). The soil cover of Jõgeva experimental area, which presents an accumulative drumlin landscape (formed during the last glacial period), consist from loamy Luvisols and associated to this Cambisols. In Kuusiku area

  5. Hydrologic Impact Of Subsurface Drainage Of Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Naz, B. S.; Johannsen, C. J.; Bowling, L. C.

    2005-12-01

    automatic detection techniques using meteorological data for 14-years (1990-2004) and 15-years (1985-2000) at both sites respectively. In general, hydrologic outputs predicted by the model were acceptable. In addition to hydrologic response of subsurface drainage network, the model simulation can also be helpful to determine the required accuracy of predicted tile location maps for analyzing hydrologic responses of agricultural fields.

  6. Experimental Evaluation of Field Trips on Instruction in Vocational Agriculture.

    ERIC Educational Resources Information Center

    McCaslin, Norval L.

    To determine the effect of field trips on student achievement in each of four subject matter areas in vocational agriculture, 12 schools offering approved programs were randomly selected and divided into a treatment group and a control group. Uniform teaching outlines and reference materials were provided to each group. While no field trips were…

  7. Temporal stability of soil water content and soil water flux patterns across agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When an agricultural field is repeatedly surveyed for soil water content, sites often can be spotted where soil is consistently wetter or consistently dryer than average across the study area. Temporal stability presents significant interest for upscaling observed soil water content, improving soil ...

  8. Wireless Site-specific Irrigation - The Future of Intelligent Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A wireless site-specific irrigation system was developed with a distributed wireless sensor network. The system allows growers to remotely access field conditions and an irrigation operation at the home or office via wireless radio communication, directing individual sprinklers on how much water to ...

  9. A contemporary decennial global sample of changing agricultural field sizes

    NASA Astrophysics Data System (ADS)

    White, E.; Roy, D. P.

    2011-12-01

    In the last several hundred years agriculture has caused significant human induced Land Cover Land Use Change (LCLUC) with dramatic cropland expansion and a marked increase in agricultural productivity. The size of agricultural fields is a fundamental description of rural landscapes and provides an insight into the drivers of rural LCLUC. Increasing field sizes cause a subsequent decrease in the number of fields and therefore decreased landscape spatial complexity with impacts on biodiversity, habitat, soil erosion, plant-pollinator interactions, diffusion of disease pathogens and pests, and loss or degradation in buffers to nutrient, herbicide and pesticide flows. In this study, globally distributed locations with significant contemporary field size change were selected guided by a global map of agricultural yield and literature review and were selected to be representative of different driving forces of field size change (associated with technological innovation, socio-economic conditions, government policy, historic patterns of land cover land use, and environmental setting). Seasonal Landsat data acquired on a decadal basis (for 1980, 1990, 2000 and 2010) were used to extract field boundaries and the temporal changes in field size quantified and their causes discussed.

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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

  11. CANTON CAFO FIELD SITE STUDY - SITE CHARACTERIZATION AND CONTAMINANT IMPACTS

    EPA Science Inventory

    This presentation of CAFO research concerning the Canton CAFO field site study, including its characterization and contaminant impacts, was given at a NRMRL program review discussion of the CAFO Research Program.

  12. Gypsum use to reduce P loss from agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Public concern regarding agriculture’s contribution to surface water quality impairment has increased in recent years. Repeated manure use on agricultural fields at agronomic N rates has created a redistribution of P in soils which increases the risk of P contribution to surface waters, deteriorat...

  13. Illinois Occupational Skill Standards: Agricultural Laboratory and Field Technician Cluster.

    ERIC Educational Resources Information Center

    Illinois Occupational Skill Standards and Credentialing Council, Carbondale.

    These Illinois skill standards for the agricultural laboratory and field technician cluster are intended to serve as a guide to workforce preparation program providers as they define content for their programs and to employers as they establish the skills and standards necessary for job acquisition. They could also serve as a mechanism for…

  14. Lidar Based Particulate Flux Measurements of Agricultural Field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A three-wavelength portable scanning lidar system was developed to derive information on particulate spatial aerosol distribution over remote distances. The lidar system and retrieval approach has been tested during several field campaigns measuring agricultural emissions from a swine feeding operat...

  15. 7 CFR Appendix A to Part 3434 - List of Agriculture-Related Fields

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false List of Agriculture-Related Fields A Appendix A to Part 3434 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HISPANIC-SERVING AGRICULTURAL COLLEGES AND UNIVERSITIES CERTIFICATION...

  16. 7 CFR Appendix A to Part 3434 - List of Agriculture-Related Fields

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false List of Agriculture-Related Fields A Appendix A to Part 3434 Agriculture Regulations of the Department of Agriculture (Continued) NATIONAL INSTITUTE OF FOOD AND AGRICULTURE HISPANIC-SERVING AGRICULTURAL COLLEGES AND UNIVERSITIES CERTIFICATION PROCESS...

  17. Use of agricultural land evaluation and site assessment in Linn County, Oregon, USA

    NASA Astrophysics Data System (ADS)

    Huddleston, J. Herbert; Pease, James R.; Forrest, William G.; Hickerson, Hugh J.; Langridge, Russell W.

    1987-07-01

    Oregon state law requires each county in the state to identify agricultural land and enact policies and regulations to protect agricultural land use. State guidelines encourage the preservation of large parcels of agricultural land and discourage partitioning of agricultural land and construction of nonfarm dwellings in agricultural areas. A land evaluation and site assessment (LESA) system was developed in Linn County to aid in the identification of agricultural land and provide assistance to decision makers concerning the relative merits of requests to partition existing parcels of ricultural land and introduce nonagricultural uses. Land evaluation was determined by calculating soil potential ratings for each agricultural soil in the county based on the soil potentials for winter wheat, annual ryegrass, permanent pasture, and irrigated sweet corn. Soil potential ratings were expressed on a scale of 0 to 150 points. The land evaluation score for a parcel consists of the weighted average soil potential rating for all of the soils in the parcel, weighted by the percentage of each soil present in the parcel. Site assessment was based on the size of a parcel and on the amount of existing conflict between agricultural and nonagricultural uses, particularly rural residential uses, both adjacent to and in the vicinity of a parcel. Parcel size refers to both size in relation to a typical field and size in relation to a typical farm unit. Conflict takes into account the number of nonfarm dwellings within 1/4 mile (0.4 km) of a parcel, the amount of the perimeter that adjoins conflicting land uses, and the residential density adjacent to the parcel. Empirical scales were derived for assigning points to each of the site assessment factors. Both parcel size and conflict were worth 75 points in the model. For parcel size, 45 points were allocated to field size and 30 points to farm-unit size. For conflict, 30 points were allocated to nonfarm dwellings within 1/4 mile and 45

  18. Pansharpening Landsat 8 Data For Improved Agricultural Field Monitoring

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Roy, D. P.

    2014-12-01

    Satellite data provide a synoptic view and have been used for agricultural applications including cropland distribution mapping, crop condition monitoring, crop production assessment, and yield prediction. The ability of satellite data to monitor agriculture reliably is dependent on many factors but is fundamentally constrained by the satellite spatial resolution relative to the field spatial dimensions. The recently launched Landsat 8 satellite has improved calibration, radiometric resolution, geometry and global data acquisition frequency over previous Landsat sensors. Pansharpening is an established technique to integrate higher spatial resolution panchromatic information with lower spatial resolution multi-spectral information. A new pansharpening algorithm is presented that is specific to Landsat 8 and that models the sensor spectral response functions to provide a universal algorithm that is computationally efficient and applicable to large volume data. Experiments conducted using Landsat 8 data acquired over agricultural regions with markedly different field dimensions in South Dakota, China, and India, are presented to demonstrate and quantify the utility of the 15m pansharpened Landsat 8 data over conventional 30m data.

  19. WIPP site and vicinity geological field trip

    SciTech Connect

    Chaturvedi, L.

    1980-10-01

    The Environmental Evaluation Group (EEG) is conducting an assessment of the radiological health risks to people from the Waste Isolation Pilot Plant (WIPP). As a part of this work, EEG is making an effort to improve the understanding of those geological issues concerning the WIPP site which may affect the radiological consequences of the proposed repository. One of the important geological issues to be resolved is the timing and the nature of the dissolution processes which may have affected the WIPP site. EEG organized a two-day conference of geological scientists, titled Geotechnical Considerations for Radiological Hazard Assessment of WIPP on January 17-18, 1980. During this conference, it was realized that a field trip to the site would further clarify the different views on the geological processes active at the site. The field trip of June 16-18, 1980 was organized for this purpose. This report provides a summary of the field trip activities along with the participants post field trip comments. Important field stops are briefly described, followed by a more detailed discussion of critical geological issues. The report concludes with EEG's summary and recommendations to the US Department of Energy for further information needed to more adequately resolve concerns for the geologic and hydrologic integrity of the site.

  20. Modeling of Movement of Field Gudgeon, Gnathopogon elongatus elongatus, in Agricultural Canals in Yatsu Paddy Fields

    NASA Astrophysics Data System (ADS)

    Takemura, Takeshi; Koizumi, Noriyuki; Mizutani, Masakazu; Mori, Atsushi; Watabe, Keiji

    It is important as quantitative information for making a decision of project sites for networking of water area, to predict reproductive process of fish population when consolidating fish-ways on points dividing fish habitat. To that end, it is necessary to predict the number of individuals migrating to new habitats. Hence, modeling of movement of individuals is necessary as a first step in population modeling. We constructed a mathematical model of movement of field gudgeon in agricultural canals, comparing with observed data obtained by our surveys. A unit time span of this model is 50 days. This model is able to consider existence of 2 types of movement, namely, individuals of sedentary type and individuals of ambulant type. Parameters of the model were decided based on observed data which correspond to 1 unit span. Next, moving distances of 6 individuals for 4 unit span were calculated using those parameters. A histogram of calculated values was similar to that of observed data which correspond to 4 unit span. The model is expected to provide an important immigration component to a population dynamics model which is currently under development. The population model is needed to predict population recovery processes where areas of paddy fields are joined in larger networks through construction of fish-ways.

  1. Natural succession impeded by smooth brome (Bromus inermis) and intermediate wheatgrass (Agropyron intermedium) in an abandoned agricultural field

    SciTech Connect

    Nelson, J.K.

    1997-11-01

    In 1975, an abandoned agricultural field at Rocky Flats Environmental Technology Site (Site) that had been cultivated for more than 38 years, was seeded with smooth brome (Bromus inermis) and intermediate wheatgrass (Agropyron intermedium). Although these species are commonly planted in reclamation and roadside seed mixtures, few studies have documented their impact on the re-establishment of native plant communities. In 1994, species richness, cover, and biomass were sampled in the agricultural field and compared to the surrounding mixed-grass prairie at the Site. The agricultural field contained only 61 plant species (62% native), compared to 143 species (81% native) in the surrounding mixed-grass prairie. Community similarity based on species presence/absence was 0.47 (Sorensen coefficient of similarity). Basal vegetative cover was 11.2% in the agricultural field and 29.1% in the mixed-grass prairie. Smooth brome and intermediate wheatgrass accounted for 93% of the relative foliar cover and 96% of the biomass in the agricultural field. The aggressive nature of these two planted species has impeded the natural succession of the agricultural field to a more native prairie community. Studies of natural succession on abandoned fields and roads in northeastern Colorado have indicated that if left alone, fields would return to their native climax state in approximately 50 years and would be approaching their native state after 20--25 years. Based on the results of this study, this agricultural field may take more than 100 years to return to a native mixed-grass prairie state and it may never achieve a native state without human intervention.

  2. Parkinson's Disease Prevalence and Proximity to Agricultural Cultivated Fields

    PubMed Central

    Yitshak Sade, Maayan; Zlotnik, Yair; Kloog, Itai; Novack, Victor; Peretz, Chava; Ifergane, Gal

    2015-01-01

    The risk for developing Parkinson's disease (PD) is a combination of multiple environmental and genetic factors. The Negev (Southern Israel) contains approximately 252.5 km2 of agricultural cultivated fields (ACF). We aimed to estimate the prevalence and incidence of PD and to examine possible geographical clustering and associations with agricultural exposures. We screened all “Clalit” Health Services members in the Negev (70% of the population) between the years 2000 and 2012. Individual demographic, clinical, and medication prescription data were available. We used a refined medication tracer algorithm to identify PD patients. We used mixed Poisson models to calculate the smoothed standardized incidence rates (SIRs) for each locality. We identified ACF and calculate the size and distance of the fields from each locality. We identified 3,792 cases of PD. SIRs were higher than expected in Jewish rural localities (median SIR [95% CI]: 1.41 [1.28; 1.53] in 2001–2004, 1.62 [1.48; 1.76] in 2005–2008, and 1.57 [1.44; 1.80] in 2009–2012). Highest SIR was observed in localities located in proximity to large ACF (SIR 1.54, 95% CI 1.32; 1.79). In conclusion, in this population based study we found that PD SIRs were higher than expected in rural localities. Furthermore, it appears that proximity to ACF and the field size contribute to PD risk. PMID:26357584

  3. Carbon dynamics within agricultural and native sites in the loess region of Western lowa

    USGS Publications Warehouse

    Manies, K.L.; Harden, J.W.; Kramer, L.; Parton, W.J.

    2001-01-01

    In order to quantify the historical changes in carbon storage that result from agricultural conversion, this study compared the carbon dynamics of two sites in the loess region of Iowa: a native prairie and a cropland. Field data were obtained to determine present-day carbon storage and its variability within a landscape (a stable ridgetop vs. eroding upper-midslope vs. depositional lower slope). Models were used to recreate the historical carbon budget of these sites and determine the cropland's potential to be a net CO2 source or sink, relative to the atmosphere. Regardless of slope position, the cropland site contains approximately half the amount of carbon as prairie. Variability in soil carbon storage within a site as a consequence of slope position is as large or larger (variations of 200-300%) than temporal variation (???200% at all slope positions). The most extreme difference in soil carbon storage between the cropland and prairie sites is found in the soil at the upper-midslope, which is the area of greatest erosion. The models estimate that 93-172% of the carbon in the original topsoil has been lost from the cropland's eroding midslope. Much of this carbon is derived from deeper soil horizons. Either a small sink or strong source of carbon to the atmosphere is created, depending on the fate of the eroded sediment and its associated carbon.

  4. The reconnaissance and siting of field hospitals.

    PubMed

    Boreham, A; Bricknell, M C M

    2002-03-01

    This paper describes the reconnaissance function for the siting of deployable field hospitals. It reports two levels of reconnaissance, theatre/operational and tactical. The paper describes the factors to be considered when conducting the reconnaissance and the format of the reconnaissance report. PMID:12024890

  5. Comparison of N2O Emissions from Soils at Three Temperate Agricultural Sites

    NASA Technical Reports Server (NTRS)

    Frolking, S. E.; Moiser, A. R.; Ojima, D. S.; Li, C.; Parton, W. J.; Potter, C. S.; Priesack, E.; Stenger, R.; Haberbosch, C.; Dorsch, P.; Peterson, David L. (Technical Monitor)

    1997-01-01

    Nitrous oxide (N2O) flux simulations by four models were compared with year-round field measurements from five temperate agricultural sites in three countries. The field sites included an unfertilized, semi-arid rangeland with low N2O fluxes in eastern Colorado, USA; two fertilizer treatments (urea and nitrate) on a fertilized grass ley cut for silage in Scotland; and two fertilized, cultivated crop fields in Germany where N2O loss during the winter was quite high. The models used were daily trace gas versions of the CENTURY model, DNDC, ExpertN, and the NASA-Ames version of the CASA model. These models included similar components (soil physics, decomposition, plant growth, and nitrogen transformations), but in some cases used very different algorithms for these processes. All models generated similar results for the general cycling of nitrogen through the agro-ecosystems, but simulated nitrogen trace gas fluxes were quite different. In most cases the simulated N20 fluxes were within a factor of about 2 of the observed annual fluxes, but even when models produced similar N2O fluxes they often produced very different estimates of gaseous N loss as nitric oxide (NO), dinitrogen (N2), and ammonia (NH3). Accurate simulation of soil moisture appears to be a key requirement for reliable simulation of N2O emissions. All models simulated the general pattern of low background fluxes with high fluxes following fertilization at the Scottish sites, but they could not (or were not designed to) accurately capture the observed effects of different fertilizer types on N2O flux. None of the models were able to reliably generate large pulses of N2O during brief winter thaws that were observed at the two German sites. All models except DNDC simulated very low N2O fluxes for the dry site in Colorado. The US Trace Gas Network (TRAGNET) has provided a mechanism for this model and site intercomparison. Additional intercomparisons are needed with these and other models and additional data

  6. Field site evaluation for seismic mine detection

    NASA Astrophysics Data System (ADS)

    Martin, James S.; Larson, Gregg D.; Rogers, Peter H.; Scott, Waymond R., Jr.; McCall, George S., II

    2002-11-01

    A system has been developed that uses audio-frequency surface seismic waves for the detection and imaging of buried landmines. The system is based on the measurement of seismic displacements immediately above buried mines using noncontacting vibrometers that interrogate the surface motion with either radar or ultrasonic signals. In laboratory tests and limited field tests the system has demonstrated the ability to detect a variety of inert antipersonnel and antitank mines with background contrast in excess of 20 dB. Current work on the system is focused on the transition from the laboratory into the field. To facilitate this, a series of experiments has been undertaken to measure the characteristics of several field test sites. The tradeoff between image contrast and scanning speed is of primary concern in evaluating the features of these sites. The field experiments have investigated the nature of ambient seismic noise, input impedance at the seismic source (a ground contacting shaker), modal content of the seismic interrogation signal, and the nature of the nonlinearities in the soil. Observed nonlinear phenomena have included harmonic generation, phase speed slowing, dispersion and spall. Although interesting, the differences between the field sites and the laboratory model do not appear to pose problems for seismic mine detection.

  7. Solid phase electron donors control denitrification in groundwater at agricultural sites

    NASA Astrophysics Data System (ADS)

    Green, C. T.; Liao, L.; Bekins, B. A.; Bohlke, J. K.

    2011-12-01

    Increased concentrations of nitrate in groundwater caused by agricultural use of chemical and organic fertilizers are a concern because of possible risks to environmental and human health. At many sites, these problems are mitigated by natural attenuation of nitrate as a result of microbially mediated denitrification of nitrate to nitrogen gas. Recent studies have clarified the factors affecting the rates and extents of denitrification in groundwater in agricultural areas. Intensive studies were conducted by the US Geological Survey to study agricultural chemicals in California, Nebraska, Washington, and Maryland using laboratory analyses, field measurements, and flow and transport modeling for monitoring well transects (0.5 to 2.5 km in length) and vertical profiles (0 to 50 m in depth). Groundwater analyses included major ion chemistry, dissolved gases, nitrogen and oxygen stable isotopes, and atmospheric age-tracers. Sediments were analyzed for concentrations of potential electron donors for denitrification, including reduced iron and sulfur, and organic carbon. Geochemical data and mass balance calculations indicated that solid-phase electron donors were an important factor controlling denitrification at these sites. To examine the generality of this result, a mathematical model of vertical flux of water, oxygen, and nitrate was developed and applied at these study sites along with 2 new study sites in Iowa and Mississippi and 8 additional sites from previous studies in Nebraska, Texas, Minnesota, Wisconsin, North Carolina, Maryland (2 sites), and New York. Model results confirmed the importance of solid phase electron donors. The normalized reaction rates on an electron flux basis tended to increase with depth from the shallow oxygen reduction zone to the underlying nitrate reduction zone. The pattern of higher rates at depth is consistent with a reaction rate controlled by solid phase donors that are depleted under oxidizing conditions near the surface and in

  8. Comparison of some quality properties of soils around land-mined areas and adjacent agricultural fields.

    PubMed

    Ozturkmen, Ali Rıza; Kavdir, Yasemin

    2012-03-01

    When agricultural lands are no longer used for agriculture and allowed to recover its natural vegetation, soil organic carbon can accumulate in the soil. Measurements of soil organic carbon and aggregate stability changes under various forms of land use are needed for the development of sustainable systems. Therefore, comparison of soil samples taken from both agricultural and nearby area close to land-mined fields where no agricultural practices have been done since 1956 can be a good approach to evaluate the effects of tillage and agriculture on soil quality. The objective of this study was to compare tillage, cropping and no tillage effects on some soil-quality parameters. Four different locations along the Turkey-Syria border were selected to determine effects of tillage and cropping on soil quality. Each location was evaluated separately because of different soil type and treatments. Comparisons were made between non-tilled and non-cropped fallow since 1956 and adjacent restricted lands that were tilled about every 2 years but not planted (T) or adjacent lands tilled and planted with wheat and lentil (P). Three samples were taken from the depths of 0-20 and 20-40 cm each site. Soil organic carbon (SOC), pH ,electrical conductivity, water soluble Ca(++), Mg(++), CO₃⁻² and HCO₃⁻, extractable potassium (K(+)) and sodium (Na(+)), soil texture, ammonium (NH₄⁺-N) and nitrate (NO(3)-N), extractable phosphorous and soil aggregate stability were determined. While the SOC contents of continuous tillage without cropping and continuous tillage and cropping were 2.2 and 11.6 g kg(-1), respectively, it was 30 g kg(-1) in non-tilled and non-planted site. Tillage of soil without the input of any plant material resulted in loss of carbon from the soil in all sites. Soil extractable NO(3)-N contents of non-tilled and non-cropped sites were greatest among all treatments. Agricultural practices increased phosphorus and potassium contents in the soil profile. P(2)O(5

  9. Characterizing phosphorus dynamics in tile-drained agricultural fields of eastern Wisconsin

    NASA Astrophysics Data System (ADS)

    Madison, Allison M.; Ruark, Matthew D.; Stuntebeck, Todd D.; Komiskey, Matthew J.; Good, Lara W.; Drummy, Nancy; Cooley, Eric T.

    2014-11-01

    Artificial subsurface drainage provides an avenue for the rapid transfer of phosphorus (P) from agricultural fields to surface waters. This is of particular interest in eastern Wisconsin, where there is a concentrated population of dairy farms and high clay content soils prone to macropore development. Through collaboration with private landowners, surface and tile drainage was measured and analyzed for dissolved reactive P (DRP) and total P (TP) losses at four field sites in eastern Wisconsin between 2005 and 2009. These sites, which received frequent manure applications, represent a range of crop management practices which include: two chisel plowed corn fields (CP1, CP2), a no-till corn-soybean field (NT), and a grazed pasture (GP). Subsurface drainage was the dominant pathway of water loss at each site accounting for 66-96% of total water discharge. Average annual flow-weighted (FW) TP concentrations were 0.88, 0.57, 0.21, and 1.32 mg L-1 for sites CP1, CP2, NT, and GP, respectively. Low TP concentrations at the NT site were due to tile drain interception of groundwater flow where large volumes of tile drainage water diluted the FW-TP concentrations. Subsurface pathways contributed between 17% and 41% of the TP loss across sites. On a drainage event basis, total drainage explained between 36% and 72% of the event DRP loads across CP1, CP2, and GP; there was no relationship between event drainflow and event DRP load at the NT site. Manure applications did not consistently increase P concentrations in drainflow, but annual FW-P concentrations were greater in years receiving manure applications compared to years without manure application. Based on these field measures, P losses from tile drainage must be integrated into field level P budgets and P loss calculations on heavily manured soils, while also acknowledging the unique drainage patterns observed in eastern Wisconsin.

  10. Observation of soil moisture variability in agricultural and grassland field soils using a wireless sensor network

    NASA Astrophysics Data System (ADS)

    Priesack, Eckart; Schuh, Max

    2014-05-01

    Soil moisture dynamics is a key factor of energy and matter exchange between land surface and atmosphere. Therefore long-term observation of temporal and spatial soil moisture variability is important in studying impacts of climate change on terrestrial ecosystems and their possible feedbacks to the atmosphere. Within the framework of the network of terrestrial environmental observatories TERENO we installed at the research farm Scheyern in soils of two fields (of ca. 5 ha size each) the SoilNet wireless sensor network (Biogena et al. 2010). The SoilNet in Scheyern consists of 94 sensor units, 45 for the agricultural field site and 49 for the grassland site. Each sensor unit comprises 6 SPADE sensors, two sensors placed at the depths 10, 30 and 50 cm. The SPADE sensor (sceme.de GmbH, Horn-Bad Meinberg Germany) consists of a TDT sensor to estimate volumetric soil water content from soil electrical permittivity by sending an electromagnetic signal and measuring its propagation time, which depends on the soil dielectric properties and hence on soil water content. Additionally the SPADE sensor contains a temperature sensor (DS18B20). First results obtained from the SoilNet measurements at both fields sites will be presented and discussed. The observed high temporal and spatial variability will be analysed and related to agricultural management and basic soil properties (bulk density, soil texture, organic matter content and soil hydraulic characteristics).

  11. Site recycling: From Brownfield to football field

    SciTech Connect

    Lee, C.; Haas, W.L.

    1995-07-01

    The Carolina Panther`s new home, Carolinas Stadium, will be impressive. It will include a 75,000-seat stadium, about 2,000 parking spaces, and a practice facility equipped with three full-sized football fields, all located on 30 acres bordering the central business district of Charlotte, NC. Fans of the NFL expansion team may never know that, until recently, 13 of those 30 acres were a former state Superfund site contaminated by a commercial scrapyard that had operated from the early 1930s to 1983. The salvage of nonferrous metals from lead-acid batteries, copper from transformers and other electrical equipment, and ferrous metal scrap from junk automobiles at the Smith Metal and Iron (SMI) site had left a complex contamination legacy. The soil contained lead, polychlorinated biphenyls (PCBs), lesser amounts of semivolatiles (polyaromatic hydrocarbons, or PAHs), and volatile organic compounds and petroleum hydrocarbons. The site had remained dormant, like many former industrial sites that have come be called {open_quotes}brownfields,{close_quotes} for nearly a decade when in 1993, Charlotte was selected as the future home of the Carolina Panthers, a National Football League expansion team. The city was able to attract the team in part by offering to redevelop the site, a prime location adjacent to the downtown area. An eight-month-long site remediation effort by HDR Engineering Inc. was completed March 31, on schedule for a June 1996 unveiling of the team`s new facility.

  12. Assessing the mitigation potential of agricultural systems by optimization of the agricultural management: A modeling study on 8 agricultural observation sites across Europe with the process based model LandscapeDNDC

    NASA Astrophysics Data System (ADS)

    Molina Herrera, Saul; Haas, Edwin; Klatt, Steffen; Kraus, David; Kiese, Ralf; Butterbach-Bahl, Klaus

    2014-05-01

    The use of mineral nitrogen (N) fertilizers increase crop yields but cause the biggest anthropogenic source of nitrous oxide (N2O) emissions and strongly contribute to surface water eutrophication (e.g. nitrate leaching). The necessity to identify affordable strategies that improve crop production while improving ecosystem services are in continuous debate between policy decision makers and farmers. In this line, a lack commitment from farmers to enforce laws might result in the reduction of benefits. For this reason, farmers should aim to increase crop production and to reduce environmental harm by the adoption of precision climate smart agriculture tools applied to management practices for instance. In this study we present optimized strategies for 8 sites (agricultural and grassland ecosystems) with long term field observation across Europe to show the mitigation potential to reduce reactive nitrogen losses under the constrain of keeping yields at observed levels. LandscapeDNDC simulations of crop yields and associated nitrogen losses (N2O emissions and NO3 leaching) were evaluated against long term field measurements. The sites presented different management regimes including the main commodity crops (maize, wheat, barley, rape seeds, etc) and fertilization amendments (synthetic and organic fertilizers) in Europe. The simulations reproduced the observed yields, captured N2O emissions and NO3 leaching losses with high statistical presicion (r2), acurrency (ME) and agreement (RMSPEn). The mitigation potentials to reduce N losses while keeping yields at observed levels for all 8 sites were assesed by Monte Carlo optimizations of the individual underlying multi year agricultural management options (timings of planting and harvest, fertilization & manure applications and rates, residues management). In this study we present for all 8 agricultural observations sites their individual mitigation potentials to reduce N losses for multi year rotations. The conclusions

  13. Optimization of agricultural field workability predictions for improved risk management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Risks introduced by weather variability are key considerations in agricultural production. The sensitivity of agriculture to weather variability is of special concern in the face of climate change. In particular, the availability of workable days is an important consideration in agricultural practic...

  14. Evaluation of the Potential for Agricultural Development at the Hanford Site

    SciTech Connect

    Evans, Robert G.; Hattendorf, Mary J.; Kincaid, Charles T.

    2000-02-25

    By 2050, when cleanup of the Hanford Site is expected to be completed, large worldwide demands to increase the global production of animal and fish protein, food, and fiber are anticipated, despite advancements in crop breeding, genetic engineering, and other technologies. The most likely large areas for expanded irrigation in the Pacific Northwest are the undeveloped East High areas of the Columbia Basin Project and non-restricted areas within the Hanford Site in south-central Washington State. The area known as the Hanford Site has all the components that favor successful irrigated farming. Constraints to agricultural development of the Hanford Site are political and social, not economic or technical. Obtaining adequate water rights for any irrigated development will be a major issue. Numerous anticipated future advances in irrigation and resource conservation techniques such as precision agriculture techniques, improved irrigation systems, and irrigation system controls will greatly minimize the negative environmental impacts of agricultural activities.

  15. Mapping soil fractal dimension in agricultural fields with GPR

    NASA Astrophysics Data System (ADS)

    Oleschko, K.; Korvin, G.; Muñoz, A.; Velazquez, J.; Miranda, M. E.; Carreon, D.; Flores, L.; Martínez, M.; Velásquez-Valle, M.; Brambila, F.; Parrot, J.-F.; Ronquillo, G.

    2008-09-01

    We documented that the mapping of the fractal dimension of the backscattered Ground Penetrating Radar traces (Fractal Dimension Mapping, FDM) accomplished over heterogeneous agricultural fields gives statistically sound combined information about the spatial distribution of Andosol' dielectric permittivity, volumetric and gravimetric water content, bulk density, and mechanical resistance under seven different management systems. The roughness of the recorded traces was measured in terms of a single number H, the Hurst exponent, which integrates the competitive effects of volumetric water content, pore topology and mechanical resistance in space and time. We showed the suitability to combine the GPR traces fractal analysis with routine geostatistics (kriging) in order to map the spatial variation of soil properties by nondestructive techniques and to quantify precisely the differences under contrasting tillage systems. Three experimental plots with zero tillage and 33, 66 and 100% of crop residues imprinted the highest roughness to GPR wiggle traces (mean HR/S=0.15), significantly different to Andosol under conventional tillage (HR/S=0.47).

  16. Agricultural Education Early Field Experience through the Lens of the EFE Model

    ERIC Educational Resources Information Center

    Smalley, Scott W.; Retallick, Michael S.

    2012-01-01

    The purpose of this national study was to describe agricultural teacher education early field experience (EFE) practices using the EFE model. The population for this study was all agricultural education teacher preparation programs (N = 83) listed in the AAAE Directory of University Faculty in Agricultural Education. Data were collected via an…

  17. Engineering and agronomy aspects of a long-term precision agriculture field experiment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Much research has been conducted on specific precision agriculture tools and implementation strategies, but little has been reported on long-term evaluation of integrated precision agriculture field experiments. In 2004 our research team developed and initiated a multi-faceted “precision agriculture...

  18. USER REQUIREMENTS FOR SATELLITE AND OTHER REMOTE SENSING INFORMATION IN THE FIELD OF AGRICULTURAL METEOROLOGY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report presents the current remote sensing technology that is applicable to the field of agricultural meteorology. The information presented is applicable for monitoring and assessment of agricultural crops and grasslands and their impact on agricultural production at regional and national lev...

  19. Forests to fields. Restoring tropical lands to agriculture.

    PubMed

    Wood, D

    1993-04-01

    In discussing land use in tropical forest regions, there is an emphasis on the following topics: the need for the expansion of cropping areas, the precedent for use of the tropical forest for cropping based on past use patterns, the pressure from conservationists against cropping, debunking the mythology that forests are "natural" and refuting the claims that forest clearance is not reversible, the archeological evidence of past forest use for agricultural purposes, abandonment of tropical land to forest, and rotation of forest and field. The assumption is that the way to stop food importation is to increase crop production in the tropics. Crop production can be increased through 1) land intensification or clearing new land, 2) output per unit of land increases, or 3) reallocation to agriculture land previously cleared and overgrown with tropical forest. "Temporary" reuse of land, which reverted back to tropical forest, is recommended. This reuse would ease population pressure, and benefit bioconservation, while populations stabilize and further progress is made in international plant breeding. The land would eventually be returned to a forest state. Conservation of tropical forest areas should be accomplished, after an assessment has been made of its former uses. Primary forests need to identified and conversion to farming ceased. Research needs to be directed to understanding the process of past forest regeneration, and to devising cropping systems with longterm viability. The green revolution is unsuitable for traditional cropping systems, is contrary to demands of international funding agencies for sustainability, and is not affordable by most poor farmers. Only .48 million sq. km of closed forest loss was in tropical rainforests; 6.53 million sq. km was lost from temperate forests cleared for intensive small-scale peasant farming. The use of tropical forest land for farming has some benefits; crops in the wetter tropics are perennial, which would "reduce

  20. Modeling water outflow from tile-drained agricultural fields.

    PubMed

    Kuzmanovski, Vladimir; Trajanov, Aneta; Leprince, Florence; Džeroski, Sašo; Debeljak, Marko

    2015-02-01

    The estimation of the pollution risk of surface and ground water with plant protection products applied on fields depends highly on the reliable prediction of the water outflows over (surface runoff) and through (discharge through sub-surface drainage systems) the soil. In previous studies, water movement through the soil has been simulated mainly using physically-based models. The most frequently used models for predicting soil water movement are MACRO, HYDRUS-1D/2D and Root Zone Water Quality Model. However, these models are difficult to apply to a small portion of land due to the information required about the soil and climate, which are difficult to obtain for each plot separately. In this paper, we focus on improving the performance and applicability of water outflow modeling by using a modeling approach based on machine learning techniques. It allows us to overcome the major drawbacks of physically-based models e.g., the complexity and difficulty of obtaining the information necessary for the calibration and the validation, by learning models from data collected from experimental fields that are representative for a wider area (region). We evaluate the proposed approach on data obtained from the La Jaillière experimental site, located in Western France. This experimental site represents one of the ten scenarios contained in the MACRO system. Our study focuses on two types of water outflows: discharge through sub-surface drainage systems and surface runoff. The results show that the proposed modeling approach successfully extracts knowledge from the collected data, avoiding the need to provide the information for calibration and validation of physically-based models. In addition, we compare the overall performance of the learned models with the performance of existing models MACRO and RZWQM. The comparison shows overall improvement in the prediction of discharge through sub-surface drainage systems, and partial improvement in the prediction of the surface

  1. Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture within the United States is varied and produces a large value ($200 billion in 2002) of production across a wide range of plant and animal production systems. Because of this diversity, changes in climate will likely impact agriculture throughout the United States. Climate affects crop, ...

  2. A quantitative phosphorus loss assessment tool for agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation and nutrient management planners need an assessment tool to accurately predict phosphorus (P) loss from agricultural lands. Available tools are either qualitative indices with limited capability to quantify offsite water quality impacts or prohibitively complex quantitative process-bas...

  3. Occurrence of an herbicide-resistant plant trait in agricultural field margins.

    PubMed

    Gage, Karla L; Gibson, David J; Young, Bryan G; Young, Julie M; Matthews, Joseph L; Weller, Stephen C; Wilson, Robert G

    2015-09-01

    Agricultural environments allow study of evolutionary change in plants. An example of evolution within agroecological systems is the selection for resistance to the herbicide glyphosate within the weed, Conyza canadensis. Changes in survivorship and reproduction associated with the development of glyphosate resistance (GR) may impact fitness and influence the frequency of occurrence of the GR trait. We hypothesized that site characteristics and history would affect the occurrence of GR C. canadensis in field margins. We surveyed GR occurrence in field margins and asked whether there were correlations between GR occurrence and location, crop rotation, GR crop trait rotation, crop type, use of tillage, and the diversity of herbicides used. In a field experiment, we hypothesized that there would be no difference in fitness between GR and glyphosate-susceptible (GS) plants. We asked whether there were differences in survivorship, phenology, reproduction, and herbivory between 2 GR and 2 GS populations of C. canadensis in agrestal and ruderal habitats. We found that geographic location was an important factor in the occurrence of GR C. canadensis in field margins. Although not consistently associated with either glyphosate resistance or glyphosate susceptibility, there were differences in phenology, survivorship, and herbivory among biotypes of C. canadensis. We found equal or greater fitness in GR biotypes, compared to GS biotypes, and GR plants were present in field margins. Field margins or ruderal habitats may provide refugia for GR C. canadensis, allowing reproduction and further selection to occur as seeds recolonize the agrestal habitat. Agricultural practices may select for ecological changes that feed back into the evolution of plants in ruderal habitats. PMID:26445665

  4. Aproaches for mitigation of greenhouse gas emission from agricultural fields

    NASA Astrophysics Data System (ADS)

    Sudo, S.; Itoh, M.

    2009-12-01

    Percentage of atmospheric methane emitted form rice paddy is estimated at 60Tg/yr (20 - 100Tg/yr) which is near 10% of total global methane emission of 535Tg/yr (410 - 660Tg) (IPCC(1995), and which is near 30% of anthropogenic CH4 emission. Thus, mitigation of CH4 emission is required to be speed up. CH4 in paddy soil is emanated by the activities of anaerobic bacteria which is called methane producer through reduction of CO2 or decomposition of acetic acid, and it is transported to atmosphere through soil or paddy water surface. It is effective to control methane emission from rice paddy that period is prolonged on intermittent irrigation drainage, composted rice straw is incorporated as fertilizer instead of flesh one, or other. However, empirical approach of these kinds of experiments had not been sufficient because such a kind of experiment required significant times and efforts. In this study, we conducted demonstrative experiments to verify the effects of water management method differences in order to reduce CH4 emission from rice paddy at 9 experimental sites in 8 prefectures. In this, we used new gas analyzer which can measure CH4, CO2 and N2O at once developed by National Institute for Agro-Environmental Sciences (NIAES), Japan. In this report, we show the preliminary results in first year of this study. Nakaboshi (mid-season-drainage) is one of cultivation methods in rice paddy that surface water in paddy field is once drained for about 10 days and the field is maintained like upland field to give adequate stress to rice plant for better harvest qualities and yields. Our targeted evaluation was dependencies of Nakaboshi periods lengths and Nakaboshi periods to CH4 emission reduction amounts for total cultivation periods within harvest yield maintained. The longer length of Nakaboshi period was prolonged, the lesser emission amounts of CH4 decreased even after when Nakaboshi period lasted, as a whole. In some soil types, for example in Kagoshima

  5. Distribution of uranium in soil components of agricultural fields after long-term application of phosphate fertilizers.

    PubMed

    Yamaguchi, N; Kawasaki, A; Iiyama, I

    2009-02-01

    Long-term application of phosphate fertilizers causes accumulation of U in the surface soil of agricultural fields. We investigated the soil constituents that contribute to the accumulation of U by using chemical extraction methods. Surface soil samples were obtained from upland fields, pastures, and paddy fields cultivated without any phosphate fertilizer (control site), with NPK fertilizer (NPK site), and with both NPK fertilizer and compost (NPK+compost site) for more than 20 years. In addition to the total U (Ut) concentration in soil, the concentrations of pyrophosphate- and acid oxalate-extractable U were determined as a measure of U associated with soil organic matter and poorly crystalline Fe/Al minerals in soil, respectively. The total, pyrophosphate-extractable, and acid oxalate-extractable U concentrations were higher in the soil obtained from the NPK and NPK+compost sites than in that obtained from the control site. The difference in the U concentrations between the NPK or NPK+compost site and the control site corresponded with the increased U concentration observed after the application of the phosphate fertilizer or both the fertilizer and compost. In the upland field and pasture soil, the increase in pyrophosphate-extractable U was 83-94% of that in Ut. On the other hand, the increase in acid oxalate-extractable U was 44-58% of that in Ut in the upland field and pasture soil, but it was almost equivalent to the increase in Ut in the paddy soil with NPK. In conclusion, most of the phosphate fertilizer-derived U was either incorporated into the soil organic matter or poorly crystalline Fe/Al minerals in the surface soil of agricultural fields. Thus, soil organic matter is an important pool of U in upland field and pasture soil, whereas poorly crystalline Fe/Al minerals are important pools of U in paddy soil experiencing alternating changes in redox conditions. PMID:19033080

  6. Rural Housing Site Planning in North Carolina. Agricultural Extension Publication 105.

    ERIC Educational Resources Information Center

    Hester, Randolph T., Jr.; And Others

    Addressing the problems of rural housing site selection and development in North Carolina, this guide is designed for cooperative and coordinated use by: technical assistance personnel employed by the Farmers Home Administration; local lending institutions; Health Departments; the Agricultural Extension Service; the Soil Conservation Service; and…

  7. Multispectral Imaging Systems for Airborne Remote Sensing to Support Site-Specific Agricultural Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Remote sensing has shown promise as a tool for site-specific management in agricultural application and production. Earth-observing satellite systems have an advantage for large-scale analysis at regional levels but are limited in spatial resolution. High-resolution satellite systems have been avail...

  8. Semiparametric Geographically Weighted Response Curves with Application to Site Specific Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lack of basic knowledge about spatial and treatment varying crop response to irrigation hinders irrigation management and economic analysis for site-specific agriculture. One model that has been postulated for relating crop-specific economic quantities to irrigation is a quadratic response curve of...

  9. On-site denitrification beds could reduce indirect greenhouse gas emissions from agricultural drainage waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitrate (NO3-) laden agricultural drainage waters are non-point sources of indirect nitrous oxide (N2O) emissions, which represent a significant fraction of total N2O emissions in the USA. On-site denitrification beds filled with woodchips were used to reduce NO3- under carbon rich anaerobic conditi...

  10. Field experiments to evaluate nitrate-leaching from drained agriculturally used areas

    NASA Astrophysics Data System (ADS)

    Bednorz, Denise; Tauchnitz, Nadine; Christen, Olaf; Rupp, Holger; Meissner, Ralph

    2016-04-01

    Agricultural land use is one of the main sources for diffuse nitrogen (N) inputs into surface- and groundwater. To fulfill the objectives of the European water protection policy it is mandatory to optimize agricultural management and to adopt it to site specific conditions. N present in soil is dominated by organic N, and after mineralization inorganic plant available N, obtaining the components ammonia and nitrate (NO3-N). In the environment, NO3-N occurs as the negatively charged ion NO3- which is generally solved. Thus, NO3-N is the major N-species in waters, whereas its transport is directly influenced by the flow regime. In dependence of soil type and meteorological conditions, subsurface drainage was often installed to prevent water logged zones as a requirement for agricultural use. But drainage systems were often discussed as one of the main sources for NO3-N inputs into surface water due to temporary high discharge rates and short residence time of soil water resulting in limited conditions for NO3-N degradation via denitrification. In the study presented herein, two adjacent tile-drained agriculturally used areas with adjusted agronomic conditions but different soil properties were investigated regarding their flow regime and their N-kinetic from 11/1/2013 until 10/31/2015. Both fields obtained the same size and drainage network (drain depth 0.8 m, gab distance 10 m). Field I was influenced by confined groundwater conditions due to an alternating strata of sandy and loamy layers. Field II was impermeable from a depth of one meter, showing a backwater influenced flow regime. The temporal course of soil moisture (35, 60 and 85 cm depth), drain rate as well as ground- and backwater head was registered continuously at both sites. Furthermore NH4-N- and NO3-N-concentrations (cNO3-N) in each compartment were measured. The experimental results showed that field I revealed significantly lower discharged drain rates and NO3-N-loads (17.1 mm and 2.5 kg N

  11. To and From the Field: Communications and Agriculture.

    ERIC Educational Resources Information Center

    Development Communication Report, 1978

    1978-01-01

    Information on current research and projects, as well as general suggestions and conceptual material, is presented in 11 articles related to communication in rural areas of developing nations. These articles deal with (1) how information flows to small Nepalese farms; (2) an overview of communication in agricultural development projects, with…

  12. Thermal Infrared Imagery for Better Water Conservation in Agricultural Fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water conservation is an issue that involves all citizens in Georgia. Within the agricultural row crop community, water is a very important part of producing a harvestable and profitable product. Although irrigation is used only as a supplement to natural rainfall, it can greatly affect crop yield...

  13. Three Dimensional Modeling of Agricultural Contamination of Groundwater: a Case Study in the Nebraska Management Systems Evaluation Area (MSEA) Site

    NASA Astrophysics Data System (ADS)

    Akbariyeh, S.; Snow, D. D.; Bartelt-Hunt, S.; Li, X.; Li, Y.

    2015-12-01

    Contamination of groundwater from nitrogen fertilizers and pesticides in agricultural lands is an important environmental and water quality management issue. It is well recognized that in agriculturally intensive areas, fertilizers and pesticides may leach through the vadose zone and eventually reach groundwater, impacting future uses of this limited resource. While numerical models are commonly used to simulate fate and transport of agricultural contaminants, few models have been validated based on realistic three dimensional soil lithology, hydrological conditions, and historical changes in groundwater quality. In this work, contamination of groundwater in the Nebraska Management Systems Evaluation Area (MSEA) site was simulated based on extensive field data including (1) lithology from 69 wells and 11 test holes; (2) surface soil type, land use, and surface elevations; (3) 5-year groundwater level and flow velocity; (4) daily meteorological monitoring; (5) 5-year seasonal irrigation records; (6) 5-years of spatially intensive contaminant concentration in 40 multilevel monitoring wells; and (7) detailed cultivation records. Using this data, a three-dimensional vadose zone lithological framework was developed using a commercial software tool (RockworksTM). Based on the interpolated lithology, a hydrological model was developed using HYDRUS-3D to simulate water flow and contaminant transport. The model was validated through comparison of simulated atrazine and nitrate concentration with historical data from 40 wells and multilevel samplers. The validated model will be used to predict potential changes in ground water quality due to agricultural contamination under future climate scenarios in the High Plain Aquifer system.

  14. BIOREMEDIATION FIELD INITIATIVE SITE PROFILE: ESCAMBIA WOOD PRESERVING SITE - BROOKHAVEN

    EPA Science Inventory

    The Escambia Wood Preserving Site—Brookhaven in Brookhaven, Mississippi, is a former wood preserving facility that used pentachlo- rophenol (PCP) and creosote to treat wooden poles. The site contains two pressure treatment cylinders, a wastewater treatment system, five bulk pr...

  15. Assessing and modelling ecohydrologic processes at the agricultural field scale

    NASA Astrophysics Data System (ADS)

    Basso, Bruno

    2015-04-01

    One of the primary goals of agricultural management is to increase the amount of crop produced per unit of fertilizer and water used. World record corn yields demonstrated that water use efficiency can increase fourfold with improved agronomic management and cultivars able to tolerate high densities. Planting crops with higher plant density can lead to significant yield increases, and increase plant transpiration vs. soil water evaporation. Precision agriculture technologies have been adopted for the last twenty years but seldom have the data collected been converted to information that led farmers to different agronomic management. These methods are intuitively appealing, but yield maps and other spatial layers of data need to be properly analyzed and interpreted to truly become valuable. Current agro-mechanic and geospatial technologies allow us to implement a spatially variable plan for agronomic inputs including seeding rate, cultivars, pesticides, herbicides, fertilizers, and water. Crop models are valuable tools to evaluate the impact of management strategies (e.g., cover crops, tile drains, and genetically-improved cultivars) on yield, soil carbon sequestration, leaching and greenhouse gas emissions. They can help farmers identify adaptation strategies to current and future climate conditions. In this paper I illustrate the key role that precision agriculture technologies (yield mapping technologies, within season soil and crop sensing), crop modeling and weather can play in dealing with the impact of climate variability on soil ecohydrologic processes. Case studies are presented to illustrate this concept.

  16. Variability of surface temperature in agricultural fields of central California

    NASA Technical Reports Server (NTRS)

    Hatfield, J. L.; Millard, J. P.; Goettelman, R. C.

    1982-01-01

    In an attempt to evaluate the relationship between hand-held infrared thermometers and aircraft thermal scanners in near-level terrain and to quantify the variability of surface temperatures within individual fields, ground-based and aircraft thermal sensor measurements were made along a 50-km transect on 3 May 1979 and a 20-km transect on 7 August 1980. These comparisons were made on fields near Davis, California. Agreement was within 1 C for fields covered with vegetation and 3.6 C for bare, dry fields. The variability within fields was larger for bare, dry fields than for vegetatively covered fields. In 1980, with improvements in the collection of ground truth data, the agreement was within 1 C for a variety of fields.

  17. Key to GHG fluxes from organic soils: site characteristics, agricultural practices or water table management?

    NASA Astrophysics Data System (ADS)

    Tiemeyer, Bärbel

    2015-04-01

    Drained peatlands are hotspots of greenhouse gas (GHG) emissions. Agriculture is the major land use type for peatlands in Germany and other European countries, but strongly varies in its intensity regarding the groundwater level and the agricultural management. Although the mean annual water table depth is sometimes proposed as an overall predictor for GHG emissions, there is a strong variability of its effects on different peatlands. Furthermore, re-wetting measures generally decrease carbon dioxide emissions, but may strongly increase methane emissions. We synthesized 250 annual GHG budgets for 120 different sites in 13 German peatlands. Carbon dioxide (net ecosystem exchange and ecosystem respiration), nitrous oxide and methane fluxes were measured with transparent and opaque manual chambers. Land management ranged from very intensive use with arable land or grassland with up to five cuts per year to partially or completely re-wetted peatlands. Besides the GHG fluxes, biomass yield, fertilisation, groundwater level, climatic data, vegetation composition and soil properties were measured. Overall, we found a large variability of the total GHG budget ranging from small uptakes to extremely high emissions (> 70 t CO2-equivalents/(ha yr)). At nearly all sites, carbon dioxide was the major component of the GHG budget. Site conditions, especially the nitrogen content of the unsaturated zone and the intra-annual water level distribution, controlled the GHG emissions of the agricultural sites. Although these factors are influenced by natural conditions (peat type, regional hydrology), they could be modified by an improved water management. Agricultural management such as the number of cuts had only a minor influence on the GHG budgets. At the level of individual peatlands, higher water levels always decreased carbon dioxide emissions. In nearly all cases, the trade-off between reduced carbon dioxide and increased methane emissions turned out in favour of the re

  18. Gully evolution in agricultural fields using ground-based LiDar

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Meeting the increasing demand for agricultural products is dependent on maintaining productive soils. Gully erosion in agricultural fields, has been shown in many regions to be as significant as sheet and rill erosion in delivering sediment to streams, rivers and lakes. Soil loss from all erosion ...

  19. Improving our ability to assess risk of phosphorus from agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eutrophication from excess phosphorus (P) loading is widespread among U.S. water bodies with a substantial portion of the P originating from agricultural fields. To reduce the impact agriculture has on water quality, USDA-NRCS includes P-based planning strategies in their 590 Standard to restrict P ...

  20. A contemporary decennial global Landsat sample of changing agricultural field sizes

    NASA Astrophysics Data System (ADS)

    White, Emma; Roy, David

    2014-05-01

    Agriculture has caused significant human induced Land Cover Land Use (LCLU) change, with dramatic cropland expansion in the last century and significant increases in productivity over the past few decades. Satellite data have been used for agricultural applications including cropland distribution mapping, crop condition monitoring, crop production assessment and yield prediction. Satellite based agricultural applications are less reliable when the sensor spatial resolution is small relative to the field size. However, to date, studies of agricultural field size distributions and their change have been limited, even though this information is needed to inform the design of agricultural satellite monitoring systems. Moreover, the size of agricultural fields is a fundamental description of rural landscapes and provides an insight into the drivers of rural LCLU change. In many parts of the world field sizes may have increased. Increasing field sizes cause a subsequent decrease in the number of fields and therefore decreased landscape spatial complexity with impacts on biodiversity, habitat, soil erosion, plant-pollinator interactions, and impacts on the diffusion of herbicides, pesticides, disease pathogens, and pests. The Landsat series of satellites provide the longest record of global land observations, with 30m observations available since 1982. Landsat data are used to examine contemporary field size changes in a period (1980 to 2010) when significant global agricultural changes have occurred. A multi-scale sampling approach is used to locate global hotspots of field size change by examination of a recent global agricultural yield map and literature review. Nine hotspots are selected where significant field size change is apparent and where change has been driven by technological advancements (Argentina and U.S.), abrupt societal changes (Albania and Zimbabwe), government land use and agricultural policy changes (China, Malaysia, Brazil), and/or constrained by

  1. PROBABILISTIC SITE IDENTIFICATION ANALYSIS USING NUPEC RECORDED FREE FIELD MOTIONS.

    SciTech Connect

    XU,J.; COSTANTINO,C.; HOFMAYER,C.; MURPHY,A.; KITADA,Y.

    2002-08-04

    THIS PAPER DESCRIBES A PROBABILISTIC SITE IDENTIFICATION ANALYSIS PERFORMED BY BNL, USING THE FREE FIELD EARTHQUAKE MOTIONS RECORDED AT THE NUPEC TEST SITE. THE BNL ANALYSIS WAS INTENDED TO PROVIDE ADEQUATE CHARACTERIZATION OF THE SOIL PROPERTIES FOR THE TEST SITE TO BE USED FOR SSI ANALYSES. THE FREE FIELD DATA WERE PROVIDED BY NUPEC. THE METHODOLOGY EMPLOYED IN THE BNL PROBABILISTIC ANALYSIS OF SITE IDENTIFICATION INCLUDES THE MONTE CARLO PR...

  2. MAC Europe 1991 campaign: AIRSAR/AVIRIS data integration for agricultural test site classification

    NASA Technical Reports Server (NTRS)

    Sangiovanni, S.; Buongiorno, M. F.; Ferrarini, M.; Fiumara, A.

    1993-01-01

    During summer 1991, multi-sensor data were acquired over the Italian test site 'Otrepo Pavese', an agricultural flat area in Northern Italy. This area has been the Telespazio pilot test site for experimental activities related to agriculture applications. The aim of the investigation described in the following paper is to assess the amount of information contained in the AIRSAR (Airborne Synthetic Aperture Radar) and AVIRIS (Airborne Visible/Infrared Imaging Spectrometer) data, and to evaluate classification results obtained from each sensor data separately and from the combined dataset. All classifications are examined by means of the resulting confusion matrices and Khat coefficients. Improvements of the classification results obtained by using the integrated dataset are finally evaluated.

  3. A Simple Runoff Model Based on Topographic Wetness Indices and Soil Moisture for Central New York Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Hofmeister, K.; Georgakakos, C.; Walter, M. T.

    2014-12-01

    Nonpoint source (NPS) pollution continues to be a leading cause of surface water degradation, especially in agricultural areas. In humid regions where variable source area (VSA) hydrology dominates, such as the Northeastern US, topographic wetness indices (TWI) are good approximations of relative soil moisture patterns. Mapping areas of the landscape likely to generate saturation-excess runoff and carry NPS pollution to surface waters could allow for more efficient, targeted best management practices in agricultural fields. Given the relationship between saturation excess runoff and soil water storage, we used volumetric water content (VWC) measured in five agricultural fields in central New York over two years (2012-2014) to develop runoff probability maps based on a soil topographic index (STI). The relationship between VWC and STI was strongest during the fall season after leaf fall at all sites except one. We calculated the probability of runoff occurring based on soil moisture and precipitation distributions during the sampling period. The threshold for runoff occurs when the depth of soil water and rainfall reach saturation of the soil, and appears to be at the average porosity of the soil at all sites. Counter to our initial hypothesis of a higher probability of saturation excess runoff during the spring when conditions are wetter, some sites showed higher frequencies of runoff during the fall season.

  4. Mapping Agricultural Fields in Sub-Saharan Africa with a Computer Vision Approach

    NASA Astrophysics Data System (ADS)

    Debats, S. R.; Luo, D.; Estes, L. D.; Fuchs, T.; Caylor, K. K.

    2014-12-01

    Sub-Saharan Africa is an important focus for food security research, because it is experiencing unprecedented population growth, agricultural activities are largely dominated by smallholder production, and the region is already home to 25% of the world's undernourished. One of the greatest challenges to monitoring and improving food security in this region is obtaining an accurate accounting of the spatial distribution of agriculture. Households are the primary units of agricultural production in smallholder communities and typically rely on small fields of less than 2 hectares. Field sizes are directly related to household crop productivity, management choices, and adoption of new technologies. As population and agriculture expand, it becomes increasingly important to understand both the distribution of field sizes as well as how agricultural communities are spatially embedded in the landscape. In addition, household surveys, a common tool for tracking agricultural productivity in Sub-Saharan Africa, would greatly benefit from spatially explicit accounting of fields. Current gridded land cover data sets do not provide information on individual agricultural fields or the distribution of field sizes. Therefore, we employ cutting edge approaches from the field of computer vision to map fields across Sub-Saharan Africa, including semantic segmentation, discriminative classifiers, and automatic feature selection. Our approach aims to not only improve the binary classification accuracy of cropland, but also to isolate distinct fields, thereby capturing crucial information on size and geometry. Our research focuses on the development of descriptive features across scales to increase the accuracy and geographic range of our computer vision algorithm. Relevant data sets include high-resolution remote sensing imagery and Landsat (30-m) multi-spectral imagery. Training data for field boundaries is derived from hand-digitized data sets as well as crowdsourcing.

  5. Pathogen transport in surface runoff from manured agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research objective: Manure application to cultivated land is a sustainable approach for enhancing soil fertility and tilth. However, enteric pathogens are often common in manure and can be transported from the application site via runoff and potentially transmitted to livestock and humans. Our objec...

  6. Topographic effects on denitrification in drained agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Denitrification is affected by soil moisture, while soil moisture can be affected by topography. Therefore, denitrification can be spatially correlated to topographic gradients. Three prior converted fields on the Delmarva Peninsula were sampled spatially for denitrification enzyme activity. The up...

  7. Successional trends in Sonoran Desert abandoned agricultural fields in northern Mexico

    USGS Publications Warehouse

    Castellanos, A.E.; Martinez, M.J.; Llano, J.M.; Halvorson, W.L.; Espiricueta, M.; Espejel, I.

    2005-01-01

    Excessive ground-water use and saline intrusion to the aquifer led, in less than three decades, to an increase in abandoned agricultural fields at La Costa de Hermosillo, within the Sonoran Desert. Using a chronosequence from years since abandonment, patterns of field succession were developed. Contrary to most desert literature, species replacement was found, both in fields with and without saline intrusion. Seasonal photosynthetic capacity as well as water and nitrogen use efficiencies were different in dominant early and late successional plant species. These ecological findings provided a framework for a general explanation of species dominance and replacement within abandoned agricultural fields in the Sonoran Desert. ?? 2004 Elsevier Ltd. All rights reserved.

  8. Economical and environmental implications of solid waste compost applications to agricultural fields in Punjab, Pakistan.

    PubMed

    Qazi, M Akram; Akram, M; Ahmad, N; Artiola, Janick F; Tuller, M

    2009-09-01

    Application of municipal solid waste compost (MSWC) to agricultural soils is becoming an increasingly important global practice to enhance and sustain soil organic matter (SOM) and fertility levels. Potential risks associated with heavy metals and phosphorus accumulations in surface soils may be minimized with integrated nutrient management strategies that utilize MSWC together with mineral fertilizers. To explore the economic feasibility of MSWC applications, nutrient management plans were developed for rice-wheat and cotton-wheat cropping systems within the Punjab region of Pakistan. Three-year field trials were conducted to measure yields and to determine the economic benefits using three management strategies and two nutrient doses. Management strategies included the application of mineral fertilizers as the sole nutrient source and application of mineral fertilizers in combination with MSWC with and without pesticide/herbicide treatments. Fertilizer doses were either based on standard N, P and K recommendations or on measured site-specific soil plant available phosphorus (PAP) levels. It was found that combining MSWC and mineral fertilizer applications based on site-specific PAP levels with the use of pesticides and herbicides is an economically and environmentally viable management strategy. Results show that incorporation of MSWC improved soil physical properties such as bulk density and penetration resistance. The PAP levels in the surface layer increased by the end of the trials relative to the initial status. No potential risks of heavy metal (Zn, Cd, Cr, Pb and Ni) accumulation were observed. Treatments comprised of MSWC and mineral fertilizer adjusted to site-specific PAP levels and with common pest management showed highest cumulative yields. A basic economic analysis revealed a significantly higher cumulative net profit and value-to-cost ratio (VCR) for all site-specific doses. PMID:19501499

  9. Pesticide Leaching from Agricultural Fields with Ridges and Furrows

    PubMed Central

    Boesten, Jos J. T. I.

    2010-01-01

    In the evaluation of the risk of pesticide leaching to groundwater, the soil surface is usually assumed to be level, although important crops like potato are grown on ridges. A fraction of the water from rainfall and sprinkler irrigation may flow along the soil surface from the ridges to the furrows, thus bringing about an extra load of water and pesticide on the furrow soil. A survey of the literature reveals that surface-runoff from ridges to furrows is a well-known phenomenon but that hardly any data are available on the quantities of water and pesticide involved. On the basis of a field experiment with additional sprinkler irrigation, computer simulations were carried out with the Pesticide Emission Assessment at Regional and Local scales model for separate ridge and furrow systems in a humic sandy potato field. Breakthrough curves of bromide ion (as a tracer for water flow) and carbofuran (as example pesticide) were calculated for 1-m depth in the field. Bromide ion leached comparatively fast from the furrow system, while leaching from the ridge system was slower showing a maximum concentration of about half of that for the furrow system. Carbofuran breakthrough from the furrow system began about a month after application and increased steadily to substantial concentrations. Because the transport time of carbofuran in the ridge soil was much longer, no breakthrough occurred in the growing season. The maximum concentration of carbofuran leaching from the ridge–furrow field was computed to be a factor of six times as high as that computed for the corresponding level field. The study shows that the risk of leaching of pesticides via the furrow soil can be substantially higher than that via the corresponding level field soil. PMID:21076668

  10. On-site cell field test support program

    NASA Astrophysics Data System (ADS)

    Staniunas, J. W.; Merten, G. P.

    1982-09-01

    Utility sites for data monitoring were reviewed and selected. Each of these sites will be instrumented and its energy requirements monitored and analyzed for one year prior to the selection of 40 Kilowatt fuel cell field test sites. Analyses in support of the selection of sites for instrumentation shows that many building sectors offered considerable market potential. These sectors include nursing home, health club, restaurant, industrial, hotel/motel and apartment.

  11. Multi-frequency and polarimetric radar backscatter signatures for discrimination between agricultural crops at the Flevoland experimental test site

    NASA Technical Reports Server (NTRS)

    Freeman, A.; Villasenor, J.; Klein, J. D.

    1991-01-01

    We describe the calibration and analysis of multi-frequency, multi-polarization radar backscatter signatures over an agriculture test site in the Netherlands. The calibration procedure involved two stages: in the first stage, polarimetric and radiometric calibrations (ignoring noise) were carried out using square-base trihedral corner reflector signatures and some properties of the clutter background. In the second stage, a novel algorithm was used to estimate the noise level in the polarimetric data channels by using the measured signature of an idealized rough surface with Bragg scattering (the ocean in this case). This estimated noise level was then used to correct the measured backscatter signatures from the agriculture fields. We examine the significance of several key parameters extracted from the calibrated and noise-corrected backscatter signatures. The significance is assessed in terms of the ability to uniquely separate among classes from 13 different backscatter types selected from the test site data, including eleven different crops, one forest and one ocean area. Using the parameters with the highest separation for a given class, we use a hierarchical algorithm to classify the entire image. We find that many classes, including ocean, forest, potato, and beet, can be identified with high reliability, while the classes for which no single parameter exhibits sufficient separation have higher rates of misclassification. We expect that modified decision criteria involving simultaneous consideration of several parameters increase performance for these classes.

  12. Infrared-temperature variability in a large agricultural field

    NASA Technical Reports Server (NTRS)

    Millard, J. P.; Goettelman, R. C.; Leroy, M. J.

    1981-01-01

    Dunnigan Agro-Meteorological Experiment airborne thermal scanner images of a large varying-terrain barley field are acquired and analyzed. Temperature variability that may occur within instantaneous fields of view (IFOV) is defined (coefficient of variation: standard deviation/mean temperature in degrees C), and the percentage of the area within various IFOV's within + or - 1, 2, 3, and 5 degrees of the mean is determined. With the exception of very rugged terrain, over 80% of the area within 4, 16, 65 and 258 ha cells was at temperatures within + or - 3 C of the mean cell temperature. Remote measurements of field temperature appeared to be slightly influenced by pixel size in the range 4 ha to 259 ha, and the area percentage within any pixel which contributes within + or - 1, 2, 3, and 5 degrees C of the mean, is nominally the same. In conclusion, no great advantage is found in utilizing a small IFOV instead of a large one for remote sensing of crop temperature.

  13. Identifying diffused nitrate sources in a stream in an agricultural field using a dual isotopic approach.

    PubMed

    Ding, Jingtao; Xi, Beidou; Gao, Rutai; He, Liansheng; Liu, Hongliang; Dai, Xuanli; Yu, Yijun

    2014-06-15

    Nitrate (NO3(-)) pollution is a severe problem in aquatic systems in Taihu Lake Basin in China. A dual isotope approach (δ(15)NNO3(-) and δ(18)ONO3(-)) was applied to identify diffused NO3(-) inputs in a stream in an agricultural field at the basin in 2013. The site-specific isotopic characteristics of five NO3(-) sources (atmospheric deposition, AD; NO3(-) derived from soil organic matter nitrification, NS; NO3(-) derived from chemical fertilizer nitrification, NF; groundwater, GW; and manure and sewage, M&S) were identified. NO3(-) concentrations in the stream during the rainy season [mean±standard deviation (SD)=2.5±0.4mg/L] were lower than those during the dry season (mean±SD=4.0±0.5mg/L), whereas the δ(18)ONO3(-) values during the rainy season (mean±SD=+12.3±3.6‰) were higher than those during the dry season (mean±SD=+0.9±1.9‰). Both chemical and isotopic characteristics indicated that mixing with atmospheric NO3(-) resulted in the high δ(18)O values during the rainy season, whereas NS and M&S were the dominant NO3(-) sources during the dry season. A Bayesian model was used to determine the contribution of each NO3(-) source to total stream NO3(-). Results showed that reduced N nitrification in soil zones (including soil organic matter and fertilizer) was the main NO3(-) source throughout the year. M&S contributed more NO3(-) during the dry season (22.4%) than during the rainy season (17.8%). AD generated substantial amounts of NO3(-) in May (18.4%), June (29.8%), and July (24.5%). With the assessment of temporal variation of diffused NO3(-) sources in agricultural field, improved agricultural management practices can be implemented to protect the water resource and avoid further water quality deterioration in Taihu Lake Basin. PMID:24686140

  14. REDUCING THE ENVIRONMENTAL IMPACT OF AGRICULTURAL AND NON-AGRICULTURAL SYSTEMS: MITIGATING OFF-SITE TRANSPORT OF PESTICIDES WITH RUNOFF

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water quality surveys have detected numerous pesticides in surface waters of urban and agricultural areas. The intense use of pesticides in highly managed turf systems and agriculture is of concern due to their potential adverse effects on the quality of surface waters, impacting drinking water reso...

  15. The Impact of Landscape Complexity on Invertebrate Diversity in Edges and Fields in an Agricultural Area

    PubMed Central

    Evans, Tracy R.; Mahoney, Meredith J.; Cashatt, Everett D.; Noordijk, Jinze; de Snoo, Geert; Musters, C. J. M.

    2016-01-01

    Invertebrate diversity is important for a multitude of ecosystem services and as a component of the larger ecological food web. A better understanding of the factors influencing invertebrate taxonomic richness and diversity at both local and landscape scales is important for conserving biodiversity within the agricultural landscape. The aim of this study was to determine if invertebrate richness and diversity in agricultural field interiors and edges in central Illinois, USA, were related to the complexity of the surrounding landscape. Our results show taxonomic richness and diversity in field edges is positively related to large scale landscape complexity, but the relationship is negative for field interiors. These unexpected results need further study. PMID:26848691

  16. The Impact of Landscape Complexity on Invertebrate Diversity in Edges and Fields in an Agricultural Area.

    PubMed

    Evans, Tracy R; Mahoney, Meredith J; Cashatt, Everett D; Noordijk, Jinze; de Snoo, Geert; Musters, C J M

    2016-01-01

    Invertebrate diversity is important for a multitude of ecosystem services and as a component of the larger ecological food web. A better understanding of the factors influencing invertebrate taxonomic richness and diversity at both local and landscape scales is important for conserving biodiversity within the agricultural landscape. The aim of this study was to determine if invertebrate richness and diversity in agricultural field interiors and edges in central Illinois, USA, were related to the complexity of the surrounding landscape. Our results show taxonomic richness and diversity in field edges is positively related to large scale landscape complexity, but the relationship is negative for field interiors. These unexpected results need further study. PMID:26848691

  17. Herbicide sorption to fine particulate matter suspended downwind of agricultural operations: field and laboratory investigations.

    PubMed

    Clymo, Amelia S; Shin, Jin Young; Holmen, Britt A

    2005-01-15

    Tillage-induced erosion of herbicides bound to airborne soil particles has not been quantified as a mechanism for offsite herbicide transport. This study quantifies the release of two preemergent herbicides, metolachlor and pendimethalin, to the atmosphere as gas- and particle-phase species during soil incorporation operations. Fine particulate matter (PM2.5) and gas-phase samples were collected at three sampling heights during herbicide disking into the soil in Davis, CA, in May 2000 and May 2001 using filter/PUF sampling. Quartz fiber filters (QFFs) were used in May 2000, and Teflon membrane filters (TMFs) were used in May 2001. The field data were combined with laboratory filter/PUF partitioning experiments to account for adsorption to the filter surfaces and quantify the mass of PM2.5-bound herbicides in the field samples. Laboratory results indicate a significant adsorption of metolachlor, but not pendimethalin, to the quartz filter surfaces. Metolachlor partitioning to PM2.5 collected on TMF filters resulted in corrected PM2.5 field partition coefficient values, Kp,corr = Cp/Cg, of approximately 10(-3.5) m3/microg, indicating its preference for the gas phase. Pendimethalin exhibited more semivolatile behavior,with Kp,corr values that ranged from 10(-3) to 10(-1) m3/ microg and increased with sampling height and distance downwind of the operation. An increase in pendimethalin enrichment at a height of 5 m suggests winnowing of finer, more sorptive soil components with corresponding higher transport potential. Pendimethalin was enriched in the PM2.5 samples by up to a factor of 250 compared to the field soil, indicating thatfurther research on the processes controlling the generation of PM-bound herbicides during agricultural operations is warranted to enable prediction of off-site mass fluxes by this mechanism. PMID:15707040

  18. Assessing the Groundwater Quality at a Saudi Arabian Agricultural Site and the Occurrence of Opportunistic Pathogens on Irrigated Food Produce.

    PubMed

    Alsalah, Dhafer; Al-Jassim, Nada; Timraz, Kenda; Hong, Pei-Ying

    2015-10-01

    This study examines the groundwater quality in wells situated near agricultural fields in Saudi Arabia. Fruits (e.g., tomato and green pepper) irrigated with groundwater were also assessed for the occurrence of opportunistic pathogens to determine if food safety was compromised by the groundwater. The amount of total nitrogen in most of the groundwater samples exceeded the 15 mg/L permissible limit for agricultural irrigation. Fecal coliforms in densities > 12 MPN/100 mL were detected in three of the groundwater wells that were in close proximity to a chicken farm. These findings, coupled with qPCR-based fecal source tracking, show that groundwater in wells D and E, which were nearest to the chicken farm, had compromised quality. Anthropogenic contamination resulted in a shift in the predominant bacterial phyla within the groundwater microbial communities. For example, there was an elevated presence of Proteobacteria and Cyanobacteria in wells D and E but a lower overall microbial richness in the groundwater perturbed by anthropogenic contamination. In the remaining wells, the genus Acinetobacter was detected at high relative abundance ranging from 1.5% to 48% of the total groundwater microbial community. However, culture-based analysis did not recover any antibiotic-resistant bacteria or opportunistic pathogens from these groundwater samples. In contrast, opportunistic pathogenic Enterococcus faecalis and Pseudomonas aeruginosa were isolated from the fruits irrigated with the groundwater from wells B and F. Although the groundwater was compromised, quantitative microbial risk assessment suggests that the annual risk incurred from accidental consumption of E. faecalis on these fruits was within the acceptable limit of 10(-4). However, the annual risk arising from P. aeruginosa was 9.55 × 10(-4), slightly above the acceptable limit. Our findings highlight that the groundwater quality at this agricultural site in western Saudi Arabia is not pristine and that better

  19. Assessing the Groundwater Quality at a Saudi Arabian Agricultural Site and the Occurrence of Opportunistic Pathogens on Irrigated Food Produce

    PubMed Central

    Alsalah, Dhafer; Al-Jassim, Nada; Timraz, Kenda; Hong, Pei-Ying

    2015-01-01

    This study examines the groundwater quality in wells situated near agricultural fields in Saudi Arabia. Fruits (e.g., tomato and green pepper) irrigated with groundwater were also assessed for the occurrence of opportunistic pathogens to determine if food safety was compromised by the groundwater. The amount of total nitrogen in most of the groundwater samples exceeded the 15 mg/L permissible limit for agricultural irrigation. Fecal coliforms in densities > 12 MPN/100 mL were detected in three of the groundwater wells that were in close proximity to a chicken farm. These findings, coupled with qPCR-based fecal source tracking, show that groundwater in wells D and E, which were nearest to the chicken farm, had compromised quality. Anthropogenic contamination resulted in a shift in the predominant bacterial phyla within the groundwater microbial communities. For example, there was an elevated presence of Proteobacteria and Cyanobacteria in wells D and E but a lower overall microbial richness in the groundwater perturbed by anthropogenic contamination. In the remaining wells, the genus Acinetobacter was detected at high relative abundance ranging from 1.5% to 48% of the total groundwater microbial community. However, culture-based analysis did not recover any antibiotic-resistant bacteria or opportunistic pathogens from these groundwater samples. In contrast, opportunistic pathogenic Enterococcus faecalis and Pseudomonas aeruginosa were isolated from the fruits irrigated with the groundwater from wells B and F. Although the groundwater was compromised, quantitative microbial risk assessment suggests that the annual risk incurred from accidental consumption of E. faecalis on these fruits was within the acceptable limit of 10−4. However, the annual risk arising from P. aeruginosa was 9.55 × 10−4, slightly above the acceptable limit. Our findings highlight that the groundwater quality at this agricultural site in western Saudi Arabia is not pristine and that better

  20. Assessment of the predictive quality of simple indicator approaches for nitrate leaching from agricultural fields

    NASA Astrophysics Data System (ADS)

    Buczko, Uwe; Kuchenbuch, Rolf

    2010-05-01

    Diffuse N losses from agriculture are a major cause of excessive nitrate concentrations in surface and groundwaters. Leaching through the soil is the main pathway of nitrate loss. For environmental management, an anticipatory assessment and monitoring of nitrate leaching risk by indicator (index) approaches is increasingly being used. Although complex Nitrogen Loss Indicator (NLI) approaches may provide more information, relatively simple NLIs may have advantages in many practical situations, for instance, when data availability is restricted. In this study, we tested four simple NLIs to asses their predictive properties: 1. N balance (Nbal); 2. exchange frequency of soil solution (EF); 3. potential nitrate concentration in leachate (PNCL); 4. a composite NLI (balance exchange frequency product, BEP). Field data of nitrate leaching from two sites in northeast Germany along with published data from several sites in Germany, Scotland and the USA were utilized. Nbal proved to be a relatively poor indicator of N loss for the time frame of one year, whereas its prediction accuracy improved for longterm averaged data. Correlation between calculated EF and experimental data was high for single year data, whereas it was lower for longterm averaged data. PNCL gave no significant correlations with measured data and high deviations. The results for BEP were intermediate between those for Nbal and EF. The results suggest that the use of EF is appropriate for assessing N leaching loss for single year data and specific sites with comparable N input and management practices, whereas for long-term averaged data, Nbal is better suited. BEP is an appropriate NLI both for single year and longterm data which accounts for source and transport factors and thus is more flexible than source based Nbal and transport based EF. However, such simplified NLIs have limitations: 1. the N cycle is not covered completely; 2. processes in the vadose zone and the aquifer are neglected, 3. assessment

  1. A Machine Learning Approach to Mapping Agricultural Fields Across Sub-Saharan Africa

    NASA Astrophysics Data System (ADS)

    Debats, S. R.; Fuchs, T. J.; Thompson, D. R.; Estes, L. D.; Evans, T. P.; Caylor, K. K.

    2013-12-01

    Food production in sub-Saharan Africa is dominated by smallholder agriculture. Rainfed farming practices and the prevailing dryland conditions render crop yields vulnerable to increasing climatic variability. As a result, smallholder farmers are among the poorest and most food insecure groups among the region's population. Quantifying the distribution of smallholder agriculture across sub-Saharan Africa would greatly assist efforts to boost food security. Existing agricultural land cover data sets are limited to estimating the percentage of cropland within a coarse grid cell. The goal of this research is to develop a statistical machine learning algorithm to map individual agricultural fields, mirroring the accuracy of hand-digitization. For the algorithm, a random forest pixel-wise classifier learns by example from training data to distinguish between fields and non-fields. The algorithm then applies this training to classify previously unseen data. These classifications can then be smoothed into coherent regions corresponding to agricultural fields. Our training data set consists of hand-digitized boundaries of agricultural fields in South Africa, commissioned by its government in 2008. Working with 1 km x 1 km scenes across South Africa, the hand-digitized field boundaries are matched with satellite images extracted from Google Maps. To highlight different information contained within the images, several image processing filters are applied. The inclusion of Landsat images for additional training information is also explored. After training and testing the algorithm in South Africa, we aim to expand our mapping efforts across sub-Saharan Africa. Through Princeton's Mapping Africa project, crowdsourcing will produce additional training data sets of hand-digitized field boundaries in new areas of interest. This algorithm and the resulting data sets will provide previously unavailable information at an unprecedented level of detail on the largest and most

  2. Evidence for atmospheric deposition of pesticides to forests bordering agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have evaluated the ability of a forested system to intercept herbicides from the air and deliver them directly by rainfall to the forest floor and then to a receiving stream within the forested area. The study was conducted over a four year period at a site in an agricultural watershed in Maryla...

  3. Global and site specific multimedia (field) studies

    SciTech Connect

    Cutshall, N.H.; Guerin, M.R.

    1987-01-01

    Experience with radioactive fallout, with organic contaminants and with heavy metals has amply demonstrated that cross-media transfers are common and that understanding the transport, cycling, and fate of these contaminants requires a multimedia approach. Nonetheless, pollutants with similar physical and chemical attributes may follow markedly different pathways. The frequency of exceptions to predictions based on simplistic models is also sufficient to show that direct investigation of environmental contamination is essential to confirm validity of models used for conceptualizing a problem or for control. Modeling based on multimedia premises and regulatory controls that encompass multimedia considerations are challenged by a dilemma, however. First, the development of multimedia models or regulatory frameworks represents simplification and generalization. This is true for several reasons: (1) inadequate understanding of physical and environmental factors which control specific cross-media transfer; (2) the absence of specific data on certain multimedia pollutant concentrations; (3) even the most powerful computers do not have sufficient speed and capacity to deal with the known complexities of natural systems. On the other hand, for contaminants such as mercury, it may be necessary to include great detail; the overall distribution in the environment may be less important than the rate of some minor process. With sufficient experience and good judgment of what can be ignored, the simplifications and generalizations can be made. For the present, and for the foreseeable future, however, they absolutely must be accompanied by thorough field validation and monitoring.

  4. Behavior of Buff-Breasted Sandpipers (Tryngites subruficollis) during Migratory Stopover in Agricultural Fields

    PubMed Central

    McCarty, John P.; Jorgensen, Joel G.; Wolfenbarger, L. LaReesa

    2009-01-01

    Background Understanding the behavior of birds in agricultural habitats can be the first step in evaluating the conservation implications of birds' use of landscapes shaped by modern agriculture. The existence and magnitude of risk from agricultural practices and the quality of resources agricultural lands provide will be determined largely by how birds use these habitats. Buff-breasted Sandpipers (Tryngites subruficollis) are a species of conservation concern. During spring migration large numbers of Buff-breasted Sandpipers stopover in row crop fields in the Rainwater Basin region of Nebraska. We used behavioral observations as a first step in evaluating how Buff-breasted Sandpipers use crop fields during migratory stopover. Methodology/Principal Findings We measured behavior during migratory stopover using scan and focal individual sampling to determine how birds were using crop fields. Foraging was the most frequent behavior observed, but the intensity of foraging changed over the course of the day with a distinct mid-day low point. Relative to other migrating shorebirds, Buff-breasted Sandpipers spent a significant proportion of their time in social interactions including courtship displays. Conclusions/Significance Our results show that the primary use of upland agricultural fields by migrating Buff-breasted Sandpipers is foraging while wetlands are used for maintenance and resting. The importance of foraging in row crop fields suggests that both the quality of food resources available in fields and the possible risks from dietary exposure to agricultural chemicals will be important to consider when developing conservation plans for Buff-breasted Sandpipers migrating through the Great Plains. PMID:19956768

  5. Extensive management of field margins enhances their potential for off-site soil erosion mitigation.

    PubMed

    Ali, Hamada E; Reineking, Björn

    2016-03-15

    Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes. PMID:26760443

  6. Argonne Terrestrial Carbon Cycle Data from Batavia Prairie and Agricultural Sites

    DOE Data Explorer

    Matamala, Roser [ANL; Jastrow, Julie D.; Lesht, Barry [ANL; Cook, David [ANL; Pekour, Mikhail [ANL; Gonzalez-Meler, Miquel A. [University of Illinois at Chicago

    Carbon dioxide fluxes and stocks in terrestrial ecosystems are key measurements needed to constrain quantification of regional carbon sinks and sources and the mechanisms controlling them. This information is required to produce a sound carbon budget for North America. This project examines CO2 and energy fluxes from agricultural land and from restored tallgrass prairie to compare their carbon sequestration potentials. The study integrates eddy covariance measurements with biometric measurements of plant and soil carbon stocks for two systems in northeastern Illinois: 1) long-term cultivated land in corn-soybean rotation with conventional tillage, and 2) a 15 year-old restored prairie that represents a long-term application of CRP conversion of cultivated land to native vegetation. The study contributes to the North American Carbon Program (NACP) by providing information on the magnitude and distribution of carbon stocks and the processes that control carbon dynamics in cultivated and CRP-restored land in the Midwest. The prairie site has been functioning since October 2004 and the agricultural site since July 2005. (From http://www.atmos.anl.gov/ FERMI/index.html)

  7. A field guide for well site geologists: Cable tool drilling

    SciTech Connect

    Last, G.V.; Liikala, T.L.

    1987-12-01

    This field is intended for use by Pacific Northwest Laboratory well site geologists who are responsible for data collection during the drilling and construction of monitoring wells on the Hanford Site. This guide presents standardized methods for geologic sample collection and description, and well construction documentation. 5 refs., 5 figs., 2 tabs.

  8. Designing a Marketing Course with Field Site Visits

    ERIC Educational Resources Information Center

    Van Doren, Doris; Corrigan, Hope Bober

    2008-01-01

    A key goal of including field site visits in marketing courses is to give business students increased interaction with industry professionals and community leaders. Site visits give students a concrete idea of how different marketing disciplines work in the business world. Business students gain greater insight into a career in marketing from this…

  9. Unraveling brackish groundwater - surface water interaction in an agricultural field using direct measurements at the field scale

    NASA Astrophysics Data System (ADS)

    Delsman, Joost; Waterloo, Maarten; Groen, Michel; Groen, Koos

    2014-05-01

    Understanding the interaction between groundwater and surface water is important for a myriad of reasons, including flow forecasting, nutrient transport, and water allocation for agriculture and other water users. This understanding is especially important in deep polder areas in the Netherlands, where brackish groundwater seepage (upward flowing regional groundwater) results in a significant salt load to surface water, and may damage crops if salts reach the rootzone in dry summers. Research on groundwater - surface water interaction historically focused on relatively pristine headwater catchments, only recently shifting somewhat to agricultural catchments. The latter pose specific research challenges, as agricultural activities and active water management can have a significant influence on hydrology. A brackish seepage flux, with a different density as precipitation, may significantly influence flow paths to surface water. Research on this specific topic is, however, lacking. We therefore investigated the interaction between groundwater and surface water in an agricultural catchment with a significant brackish seepage flux. In addition, we investigated the effects of intake of fresh water during periods of precipitation deficits, a common management strategy in lowland regions. We instrumented an agricultural ditch to enable direct, 15 min interval measurements of water fluxes and salinity to both agricultural drains and the ditch separately. These measurements are supported by piezometer nests, soil moisture sensors, temperature sensors, geophysics and a meteorological tower. Measurements focused on the summer period and were taken during two measurement periods: May 2012 - November 2012, and April 2013 - October 2013. Our measurements allowed for a direct, high-frequency separation of hydrological flow routes on this agricultural field between flow to agricultural drains and the ditch. The salinity of seepage water allowed for a relatively easy separation of

  10. Geostatistical analysis of the soil and crop parameters in a field experiment on precision agriculture

    NASA Astrophysics Data System (ADS)

    Sidorova, V. A.; Zhukovskii, E. E.; Lekomtsev, P. V.; Yakushev, V. V.

    2012-08-01

    A thorough geostatistical analysis was performed of the spatial variability of the soil properties, the sowing parameters, and the wheat yield in a field experiment under precision agriculture conditions. It was found that most of the soil parameters are significantly correlated and can be successfully mapped using kriging procedures, which ensure the optimum development of agrochemical cartograms for agricultural fields. It was also shown that the sowing parameters had a significantly lower spatial correlation; their cartograms could be drawn, although with worse accuracy. The quality parameters of the wheat grain showed no spatial correlation.

  11. PROBABILISTIC SITE IDENTIFICATION ANALYSIS USING NUPEC RECORDED FREE FIELD MOTIONS.

    SciTech Connect

    XU,J.; COSTANTINO,C.; HOFMAYER,C.; MURPHY,A.; KITADA,Y.

    2002-08-04

    THIS PAPER DESCRIBES A PROBABILISTIC SITE IDENTIFICATION ANALYSIS PERFORMED BY BNL, USING THE FREE FIELD EARTHQUAKE MOTIONS RECORDED AT THE NUPEC TEST SITE. THE BNL ANALYSIS WAS INTENDED TO PROVIDE ADEQUATE CHARACTERIZATION OF THE SOIL PROPERTIES FOR THE TEST SITE TO BE USED FOR SSI ANALYSES. THE FREE FIELD DATA WERE PROVIDED BY NUPEC. THE METHODOLOGY EMPLOYED IN THE BNL PROBABILISTIC ANALYSIS OF SITE IDENTIFICATION INCLUDES THE MONTE CARLO PROCESS IN CONJUNCTION WITH EQUIVALENT LINEARCONVOLUTION ANALYSES FOR GENERATING A LARGE NUMBER OF SITE PROFILES FOR USE IN CONVOLUTION STUDIES FROM WHICH MEAN ESTIMATES OF RESPONSE CAN BE GENERATED. THE RANDOM VARIABLE SELECTED TO CHARACTERIZE THE SITE PROFILE IS THE SHEAR WAVE VELOCITY IN EACH SOIL LAYER OF THE SITE PROFILE. A LOGNORMAL DISTRIBUTION WAS ASSUMED WITH THE STANDARD DEVIATION DETERMINED FROM AVAILABLE SITE DATA AND APPLICABLE REGULATORY REQUIREMENTS. THE CONVOLUTION ANALYSES WERE PERFORMED USING AN APPROPRIATE SOILDEGRADATION MODEL AN D THE OUTCROP INPUT MOTIONS GENERATED FROM THE RECORDED IN ROCK MOTIONS. THE BNL ANALYSIS PRODUCED RESULTS IN TERMS OF THE MEAN, MEDIAN AND VARIOUS FRACTILES OF FREE FIELD SOIL PROPERTIES AT THE TEST SITE, AND THE CORRESPONDING SURFACE RESPONSE SPECTRA, WHICH ARE PRESENTED IN THIS PAPER.

  12. Field Studies Show That In Situ Greenhouse Gas Emission Factors for East African Agriculture Are Less Than IPCC Values

    NASA Astrophysics Data System (ADS)

    Pelster, D.; Butterbach-Bahl, K.; Rufino, M.; Rosenstock, T. S.; Wanyama, G.

    2015-12-01

    Greenhouse gas (GHG) emissions from African agricultural systems are thought to comprise a large portion of total emissions from the continent, however these estimates have been calculated using emission factors (EF) from other regions due to the lack of field studies in Africa, which results in large uncertainties for these estimates. Field measurements from western Kenya calculating emissions over a year in 59 different sites found that GHG emissions from typical smallholder farms ranged from 2.8 to 15.0 Mg CO2-C ha-1, -6.0 to 2.4 kg CH4-C ha-1 and -0.1 to 1.8 kg N2O-N ha-1, and were not affected by management intensity. The lack of a response in N2O emissions to N fertilization suggests that the EF currently used in national inventories overestimates N2O emissions from typical smallholder agriculture. Another study measuring N2O and CH4 emissions from manure deposited by grazing cattle found that the N2O EF ranged from 0.1 to 0.2%, while the CH4 EF ranged from 0.04 to 0.14 Kg CH4-C per 173 kg animal. These suggest that the current IPCC EF overestimate agricultural soil and manure GHG emissions for Kenya, and likely for much of East Africa.

  13. Bird use of agricultural fields under reduced and conventional tillage in the Texas Panhandle

    USGS Publications Warehouse

    Flickinger, Edward L.; Pendleton, G.W.

    1994-01-01

    We conducted bird surveys in reduced-tillage and conventional tillage fields in spring, summer, fall, and winter from 1987 to 1991 in the Texas Panhandle. Eastern meadowlarks, longspurs, and savannah sparrows were more common in reduced-tillage (sorghum and wheat stubble) fields than in conventionally tilled (plowed) fields in at least 1 season. Other species also had patterns suggestive of greater abundance in reduced-tillage fields. Hornedlarks, which prefer habitat with sparse vegetation, were more abundant in plowed fields in all seasons except summer. Bird diversity was greater in reduced-tillage fields than in conventionally tilled fields in summer. Cover density and height were greater in reduced tillage fields in all seasons except spring. Cover density and height rather than cover composition (e.g.,grain stubble or live plants) seemed to be the important factors affecting bird distribution. Patterns of bird abundance between sorghum and wheat stubble fields also were dependent on cover. Herbicide use was not greater in reduced-tillage fields than in conventionally tilled fields. Reduced-tillage agriculture for sorghum and wheat farming should be encouraged in the southern Great Plains as a means of improving the attractiveness of agricultural land to many bird species.

  14. Using GIS to Quantify Riparian Buffer Bypassing on Agricultural Fields in the Chesapeake Bay Watershed

    NASA Astrophysics Data System (ADS)

    Funkhouser, L.; Hancock, G. S.; Kaste, J. M.

    2011-12-01

    Forested riparian buffers are intended to reduce the sediment and nutrient loads to streams delivered by agricultural runoff. Within the Chesapeake Bay Watershed, buffers are mandated to be 100' wide along agricultural fields bordered by perennial streams. When flow into buffers is widely disseminated buffers have the potential to significantly reduce pollutant levels entering streams. However, several studies show that flow across buffers is often concentrated, producing channelized flow that bypasses the buffer and presumably reduces buffer effectiveness. Previous studies have relied on field observations in relatively few locations, however, and the extent of bypassing is not well constrained. We hypothesize that buffer bypassing and the associated reduction in buffer effectiveness is a widespread phenomenon. Here we use GIS to determine flow patterns on agricultural fields and to identify locations of concentrated flow through buffers in the Virginia Coastal Plain within the Chesapeake Bay Watershed. Using DEMs with ≤10m resolution, we determine flow accumulation along field margins and identify points with flow accumulation sufficient to generate concentrated flow into buffers. Preliminary data from ~20 fields has been obtained by creating a field outline attached to flow accumulation points generated in ArcMap. We find that 66% to 91% of the total area draining to the field margins pass through discrete points representing <5% of the field margin length. On-field observations show evidence for surface flow and channelization at approximately 90% of the discrete drainage points identified in our hydrologic analysis using GIS. Our preliminary observations suggest buffer bypassing is widespread in this region of relatively low relief. We will present GIS and field analysis from a total of ~50 fields and attempt to identify the area/slope relationship necessary to generate channelization and bypassing at field margins.

  15. Occurrence and movement of antibiotic resistant bacxteria, in tile-drained agricultural fields receiving swine manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of tylosin at subtherapeutic levels by the swine industry provides selective pressure for the development of antibiotic resistance in gastrointestinal bacteria. The land application of swine manure to drained agricultural fields might accelerate the transport of pathogen indicators such as e...

  16. Use of airborne hyperspectral imagery to map soil parameters in tilled agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil hyperspectral reflectance imagery was obtained from an airborne imaging spectrometer (400 to 2450 nm with ~10 nm resolution, 2.5 m spatial resolution) flown over six tilled (bare soil) agricultural fields on the Eastern Shore of the Chesapeake Bay (Queen Anne’s county, MD). Surface soil samples...

  17. Modeling Long-Term Soil Losses on Agricultural Fields Due to Ephemeral Gully Erosion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It is now recognized worldwide that soil erosion on agricultural fields due to ephemeral gullies may be greater than those losses attributed to sheet and rill erosion processes. Yet it is not known whether the common practice of repairing or obliterating these gullies during annual tillage activitie...

  18. Anthropogenic effects on soil quality in ancient terraced agricultural fields of Chihuahua, Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural soil quality was investigated in ancient field systems near Casas Grandes (also known as Paquimé), one of the largest and most complex prehistoric settlements in the North American Southwest. This research was completed as part of an interdisciplinary study of the anthropogenic ecology...

  19. Simple, Low-Cost Data Collection Methods for Agricultural Field Studies.

    ERIC Educational Resources Information Center

    Koenig, Richard T.; Winger, Marlon; Kitchen, Boyd

    2000-01-01

    Summarizes relatively simple and inexpensive methods for collecting data from agricultural field studies. Describes methods involving on-farm testing, crop yield measurement, quality evaluations, weed control effectiveness, plant nutrient status, and other measures. Contains 29 references illustrating how these methods were used to conduct…

  20. 140° view of two agricultural fields with traces of irrigation ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    140° view of two agricultural fields with traces of irrigation ditches south of the lower holding pond. This negative forms a 360° composite panoramic when joined with AZ-2-75 and AZ-2-76. See AZ-2-86 for color version. - Tassi Ranch, Tassi Springs, Littlefield, Mohave County, AZ

  1. Definition of zones with different levels of productivity within an agricultural field using fuzzy modeling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zoning of agricultural fields is an important task for utilization of precision farming technology. One method for the definition of zones with different levels of productivity is based on fuzzy indicator model. Fuzzy indicator model for identification of zones with different levels of productivit...

  2. Status of Job Motivation and Job Performance of Field Level Extension Agents in Ogun State: Implications for Agricultural Development

    ERIC Educational Resources Information Center

    Fabusoro, E.; Awotunde, J. A.; Sodiya, C. I.; Alarima, C. I.

    2008-01-01

    The field level extension agents (FLEAs) are the lifeline of the agricultural extension system in Nigeria. Their motivation and job performance are therefore important to achieving faster agricultural development in Nigeria. The study identified the factors motivating the FLEAs working with Ogun State Agricultural development programme (OGADEP)…

  3. Californian demonstration and validation of automated agricultural field extraction from multi-temporal Landsat data

    NASA Astrophysics Data System (ADS)

    Yan, L.; Roy, D. P.

    2013-12-01

    The spatial distribution of agricultural fields is a fundamental description of rural landscapes and the location and extent of fields is important to establish the area of land utilized for agricultural yield prediction, resource allocation, and for economic planning. To date, field objects have not been extracted from satellite data over large areas because of computational constraints and because consistently processed appropriate resolution data have not been available or affordable. We present a fully automated computational methodology to extract agricultural fields from 30m Web Enabled Landsat data (WELD) time series and results for approximately 250,000 square kilometers (eleven 150 x 150 km WELD tiles) encompassing all the major agricultural areas of California. The extracted fields, including rectangular, circular, and irregularly shaped fields, are evaluated by comparison with manually interpreted Landsat field objects. Validation results are presented in terms of standard confusion matrix accuracy measures and also the degree of field object over-segmentation, under-segmentation, fragmentation and shape distortion. The apparent success of the presented field extraction methodology is due to several factors. First, the use of multi-temporal Landsat data, as opposed to single Landsat acquisitions, that enables crop rotations and inter-annual variability in the state of the vegetation to be accommodated for and provides more opportunities for cloud-free, non-missing and atmospherically uncontaminated surface observations. Second, the adoption of an object based approach, namely the variational region-based geometric active contour method that enables robust segmentation with only a small number of parameters and that requires no training data collection. Third, the use of a watershed algorithm to decompose connected segments belonging to multiple fields into coherent isolated field segments and a geometry based algorithm to detect and associate parts of

  4. Identification of vulnerable sites in salts affected agricultural soils from South-Eastern Spain

    NASA Astrophysics Data System (ADS)

    Acosta, Jose A.; Faz, Angel; Kalbitz, Karsten; Jansen, Boris; Silvia, Martinez-Martinez

    2010-05-01

    Soil salinization is one of the main problems in many soils under intensive agricultural practices, especially in arid and semiarid zones. Two important reasons for the occurrence of salinization are i) the use of low quality irrigation water and ii) climatic conditions reducing soil quality. The results of salinization can be quite serious. It limits the growing of crops, constrains agricultural productivity, and in severe cases, leads to the abandonment of agricultural soils. There are mainly two kinds of soil salinity: naturally occurring dry-land salinity and human-induced salinity caused by the low quality of irrigation water, excessive water and fertilizer applications. In both cases the development of plants and soil organisms is limited. Natural occurrence of salts in soils is very difficult to handle and requires higher investments than the reduction of human-induced salinity. For these reasons, identification of vulnerable sites is essential for sustainable agricultural management, especially in these semiarid and arid environments. The main aim of this study was to examine spatial and vertical distribution pattern of salts in a semi-arid study site in South-Eastern Spain in order to identify vulnerable sites. In order to achieve this objective, surface soil samples were collected in January and July 2009 at 48 sites located in a representative lemon production area close to City of Murcia, covering a surface area of 44 km2. The area was divided using a square grid of 1000 m and the samples were taken from these squares. The ionic concentrations were used as the input data for distribution maps. The software used for the spatial analysis was Arcview 3.1. An interpolation method called the Inverse Distanced Weighted (IDW) method was adopted for the interpolation of the data. The results indicated that the concentrations of most anions are higher in summer. The difference was particularly large for chloride, most likely because of its high mobility and

  5. Evaluation of the potential for agricultural development at the Hanford Site

    SciTech Connect

    RG Evans; MJ Hattendorf; CT Kincaid

    2000-02-25

    By 2050, when cleanup of the Hanford Site is expected to be completed, large worldwide demands to increase the global production of animalhlish protein, food, and fiber are anticipated, despite advancements in crop breeding, genetic engineering, and other technologies. World population is projected to double to more than 12 billion people, straining already stressed worldwide agricultural resources. The current world surpluses in many commodities will not last when faced with increasing population, decreasing ocean fisheries, and rapid loss of productive lands from soil salivation and erosion. The production of pharmaceuticals from bioengineered plants and animals will undoubtedly add more pressure on the already limited (and declining) arable land base. In addition there will be pressure to produce crops that can help reduce the world's dependence on petroleum and be used for chemical plant feedstock. These external, formidable pressures will necessitate increasing investments in irrigation infi-a-structures in many areas of the world to increase productivity. Intensive greenhouse culture and aqua-culture also will be greatly expanded. There will be large economic and social pressures to expand production in areas such as the Pacific Northwest. Agricultural exports will continue to be important The most likely large areas for expanded irrigation in the Pacific Northwest are the undeveloped East High areas of the Columbia Basin Project and non-restricted areas within the Hanford Site in south-central Washington State. Both of these are potentially highly productive area: for producing food and export capital. The environmental concerns will be large however, the favorable growing conditions, high-quality (low-salinity) abundant water supplies and minimal problems with salivation of soils make the Pacific Northwest a very desirable region for economically sustainable expansion from a world perspective.

  6. Automated Agricultural Field Extraction from Multi-temporal Web Enabled Landsat Data

    NASA Astrophysics Data System (ADS)

    Yan, L.; Roy, D. P.

    2012-12-01

    Agriculture has caused significant anthropogenic surface change. In many regions agricultural field sizes may be increasing to maximize yields and reduce costs resulting in decreased landscape spatial complexity and increased homogenization of land uses with potential for significant biogeochemical and ecological effects. To date, studies of the incidence, drivers and impacts of changing field sizes have not been undertaken over large areas because of computational constraints and because consistently processed appropriate resolution data have not been available or affordable. The Landsat series of satellites provides near-global coverage, long term, and appropriate spatial resolution (30m) satellite data to document changing field sizes. The recent free availability of all the Landsat data in the U.S. Landsat archive now provides the opportunity to study field size changes in a global and consistent way. Commercial software can be used to extract fields from Landsat data but are inappropriate for large area application because they require considerable human interaction. This paper presents research to develop and validate an automated computational Geographic Object Based Image Analysis methodology to extract agricultural fields and derive field sizes from Web Enabled Landsat Data (WELD) (http://weld.cr.usgs.gov/). WELD weekly products (30m reflectance and brightness temperature) are classified into Satellite Image Automatic Mapper™ (SIAM™) spectral categories and an edge intensity map and a map of the probability of each pixel being agricultural are derived from five years of 52 weeks of WELD and corresponding SIAM™ data. These data are fused to derive candidate agriculture field segments using a variational region-based geometric active contour model. Geometry-based algorithms are used to decompose connected segments belonging to multiple fields into coherent isolated field objects with a divide and conquer strategy to detect and merge partial circle

  7. Re-writing the historical perceptions of semi-arid agriculture at the abandoned site of Engaruka, NE Tanzania

    NASA Astrophysics Data System (ADS)

    Lang, Carol; Stump, Daryl

    2016-04-01

    Archaeological excavations and surveys recognised as early as the 1960s that the extensive area of archaeological remains at Engaruka in northeast Tanzania were the remnants of former settlements overlooking c. 2000ha of agricultural fields and terraces served by a complex network of irrigation canals. Given that the area is now semi-arid and receives c. 400mm of rain per year, it was naturally assumed that this irrigation was necessary in order to undertake arable cultivation. However, recent and ongoing geoarchaeological research - including stratigraphy, micromorphology and geochemistry, complemented by archaeobotany and modelling of hydrology and sediment transport - demonstrates that the site was formerly much wetter. So much wetter, in fact, that farmers built fields containing soils with paddy-like characteristics, and constructed sediment traps that accumulated vast quantities of alluvium entrained within watercourses, resulting in deposits up to 60cm deep over an area of c. 900ha, and up to 2m deep (totally some 16,000 m3) within just one large terrace covering c. 0.6ha. This paper presents the stratigraphy, micromorphology and geochemistry of the site, discusses the importance of relating this wet phase (or phases) to broader palaeoclimatic signatures covering the period of the site's occupation between the 14th and mid- to late 18th century AD, and questions if and how data of this sort can inform assessments of systemic sustainability or resilience. Acknowledgements: European Research Council Starter Grand Scheme (FP/200702013/) ERC Grant Agreement No. ERC-StG-2012-337128-AAREA

  8. Hydrogeologic and agricultural-chemical data for the South Skunk River alluvial aquifer at a site in Story County, Iowa, 1992-93

    USGS Publications Warehouse

    Buchmiller, R.C.

    1995-01-01

    A reconnaissance study was conducted during 1992-93 to collect background hydrogeologic and agricultural-chemical data for the South Skunk River alluvial aquifer near Ames, Iowa. Observation wells were drilled to characterize the surficial geologic materials of a field-scale study site and to provide locations for collecting waterlevel and agricultural-chemical data. Walnut Creek, a tributary to the South Skunk River, forms a lateral boundary on the northern edge of the field site. Water-level measurements showed a hydraulic-head gradient towards the South Skunk River under both wet and dry conditions at the study site. Walnut Creek appears to be losing water to the aquifer during most hydrologic conditions. More than 20 milligrams per liter of nitrate as nitrogen were present consistently in water from the southeastern part of the study site. Nitrate-as-nitrogen concentrations in water samples from other locations routinely did not exceed 10 milligrams per liter. The herbicide atrazine was detected most often, 36 of 38 times, in water samples collected from observation wells adjacent to Walnut Creek. Atrazine was not used on the study site during 1992-93 but was found frequently in water samples from Walnut Creek. Therefore, Walnut Creek appears to be a source of herbicide contamination to the alluvial aquifer.

  9. Optical modeling of agricultural fields and rough-textured rock and mineral surfaces

    NASA Technical Reports Server (NTRS)

    Suits, G. H.; Vincent, R. K.; Horwitz, H. M.; Erickson, J. D.

    1973-01-01

    Review was made of past models for describing the reflectance and/or emittance properties of agricultural/forestry and geological targets in an effort to select the best theoretical models. An extension of the six parameter Allen-Gayle-Richardson model was chosen as the agricultural plant canopy model. The model is used to predict the bidirectional reflectance of a field crop from known laboratory spectra of crop components and approximate plant geometry. The selected geological model is based on Mie theory and radiative transfer equations, and will assess the effect of textural variations of the spectral emittance of natural rock surfaces.

  10. Deriving a per-field land use and land cover map in an agricultural mosaic catchment

    NASA Astrophysics Data System (ADS)

    Seo, B.; Bogner, C.; Poppenborg, P.; Martin, E.; Hoffmeister, M.; Jun, M.; Koellner, T.; Reineking, B.; Shope, C. L.; Tenhunen, J.

    2014-09-01

    Detailed data on land use and land cover constitute important information for Earth system models, environmental monitoring and ecosystem services research. Global land cover products are evolving rapidly; however, there is still a lack of information particularly for heterogeneous agricultural landscapes. We censused land use and land cover field by field in the agricultural mosaic catchment Haean in South Korea. We recorded the land cover types with additional information on agricultural practice. In this paper we introduce the data, their collection and the post-processing protocol. Furthermore, because it is important to quantitatively evaluate available land use and land cover products, we compared our data with the MODIS Land Cover Type product (MCD12Q1). During the studied period, a large portion of dry fields was converted to perennial crops. Compared to our data, the forested area was underrepresented and the agricultural area overrepresented in MCD12Q1. In addition, linear landscape elements such as waterbodies were missing in the MODIS product due to its coarse spatial resolution. The data presented here can be useful for earth science and ecosystem services research. The data are available at the public repository Pangaea (doi:110.1594/PANGAEA.823677).

  11. Site study plan for cultural resources, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-06-01

    The Cultural Resources Site Study Plan describes a field program to identify and evaluate the archaeological, historical, and Native American Indian resources of the site on local and regional perspectives; monitor and manage discovered cultural resources; and establish a worker education program. The archaeological field program consists of three pedestrian surveys: Survey 1 includes two EDBH seismic survey lines and the area within the exploratory shaft facility (ESF); Survey 2 includes the remainder of the site plus a 1/4 to 3/4-mi border area; and Survey 3 includes an assortment of offsite areas. The historical studies will identify and evaluate known and discovered historical sites and structures and the Native American Indian will identify and evaluate cultural and religious concerns expressed by Indian tribal groups. Prehistoric and historic sites will be evaluated to determine if they meet eligibility criteria for listing on the National Register of Historic Places. This site study plan describes the need for each study; its design and design rationale; analysis, management, and use of data; schedule of field activities; organization of field personnel and sample management; and quality assurance requirements. The cultural resource studies will provide data for satisfying the Programmatic Agreement, engineering design needs, and SRP requirements for permits and approvals, and for minimizing effects to any cultural properties discovered during site characterization. 75 refs., 10 figs., 2 tabs.

  12. Field analytical technology verification: The ETV Site Characterization Program

    SciTech Connect

    Einfeld, W.; Jenkins, R.A.; Dindal, A.B.

    1998-06-01

    Innovative field characterization and monitoring technologies are often slow to be adopted by the environmental engineering/consulting community because of concerns that their performance has not been proven by an independent testing body, and/or they have not received the EPA`s blessing on a regional or national level. The purpose of the EPA Environmental Technology Verification (ETV) Site Characterization Pilot, a joint effort between EPA and DOE, is to accelerate the acceptance of technologies that reduce the cost and increase the speed of environmental clean-up and monitoring. Technology verifications that have been completed or are underway include: in situ technologies for the characterization of sub-surface hydrocarbon plumes, field-portable GC/MS systems, field-portable X-ray fluorescence analyzers, soil sampling technologies, field-portable PCB analyzers, analyzers for VOC analysis at the wellhead, and decision support software systems to aid site sample collection and contaminant plume definition. The verification process follows a somewhat generic pathway. A user-community need is identified, the vendor community is canvassed, and relevant, interested companies are selected. A demonstration plan is prepared by the verification organization and circulated to participants prior to the field activities. Field trials are normally held at two geologically or environmentally different sites and typically require one week at each site. Samples (soil, soil gas, water, surface wipe etc.) provided to the vendor at the demonstration include site-specific samples and standards or performance evaluation samples. Sample splits are sent to a pre-selected laboratory for analysis using a reference method. Laboratory data are used for comparison with field technology results during the data analysis phase of the demonstration.

  13. Radionuclide concentrations in agricultural products near the Hanford Site, 1982 through 1992

    SciTech Connect

    Antonio, E.J.

    1994-06-01

    The Pacific Northwest Laboratory reviewed monitoring data for agricultural products collected from 1982 through 1992 near the Hanford Site to determine radionuclide concentration trends. While samples were collected and analyzed, and results reported annual in Hanford Site environmental reports, an 11-year data set was reviewed for this report to increase the ability to assess trends and potential Hanford effects. Products reviewed included milk, chicken, eggs, beef, vegetables, fruit, wine, wheat, and alfalfa. To determine which radionuclides were detected sufficiently often to permit analysis for trends and effects, each radionuclide concentration and its associated uncertainty were ratioed. Radionuclides were considered routinely detectable if more than 50% of the ratios were between zero and one. Data for these radionuclides were then analyzed statistically, using analyses of variance. The statistical analyses indicated the following: for the most part, there were no measurable effects for Hanford operations; radionuclide concentrations in all products reviewed remained relatively low when compared to concentrations that would result in a 1-mrem effective dose equivalent to an individual; radionuclide concentrations are decreasing in general; however, {sup 90}Sr concentrations in all media and {sup 129}I in milk increased from 1982 to 1986, then decreased gradually for the remainder of the review period. The {sup 129}I concentrations may be correlated with processing of irradiated reactor fuel at the Plutonium-Uranium Extraction (PUREX) Plant.

  14. The impact of groundwater and agricultural expansion on the archaeological sites at Luxor, Egypt

    NASA Astrophysics Data System (ADS)

    Ahmed, Ayman A.; Fogg, Graham E.

    2014-07-01

    Pharaonic monuments represent the most valuable source of ancient Egypt, covering the period of approximately 3000-300 B.C. Karnak and Luxor temples represent the monuments of the east bank of Thebes, the old capital of Egypt. These monuments are currently threatened due to rising groundwater levels as a result of agricultural expansion after construction of the High Dam in the 1970s. Deterioration of archaeological sites at Luxor includes disintegration and exfoliation of stones, dissolution of building materials, loss of moral paintings, crystallization of salts in walls and columns, stone bleeding, destruction of wall paintings and texts, decreasing the durability of monumental stones, and discoloring. The hydrogeologic and climatic conditions combined with irrigation practices facilitated the weathering processes to take part in deterioration of archaeological sites at Luxor area. Many varieties of salt species are found in groundwater at the study area which react with country rocks including the archaeological foundations. These salts are not in equilibrium but in a dissolution and/or dissolution-precipitation phases which are responsible for the different types of deterioration features of Luxor and karnak temples including dissolution of the salts or minerals of the building stones and/or precipitation and crystallization of new salts.

  15. Modelling site-specific N2O emission factors from Austrian agricultural soils for targeted mitigation measures (NitroAustria)

    NASA Astrophysics Data System (ADS)

    Amon, Barbara; Zechmeister-Boltenstern, Sophie; Kasper, Martina; Foldal, Cecilie; Schiefer, Jasmin; Kitzler, Barbara; Schwarzl, Bettina; Zethner, Gerhard; Anderl, Michael; Sedy, Katrin; Gaugitsch, Helmut; Dersch, Georg; Baumgarten, Andreas; Haas, Edwin; Kiese, Ralf

    2016-04-01

    Results from a previous project "FarmClim" highlight that the IPCC default emission factor is not able to reflect region specific N2O emissions from Austrian arable soils. The methodology is limited in identifying hot spots and hot moments of N2O emissions. When estimations are based on default emission factors no recommendations can be given on optimisation measures that would lead to a reduction of soil N2O emissions. The better the knowledge is about Nitrogen and Carbon budgets in Austrian agricultural managed soils the better the situation can be reflected in the Austrian GHG emission inventory calculations. Therefore national and regionally modelled emission factors should improve the evidence for national deviation from the IPCC default emission factors and reduce the uncertainties. The overall aim of NitroAustria is to identify the drivers for N2O emissions on a regional basis taking different soil types, climate, and agricultural management into account. We use the LandscapeDNDC model to update the N2O emission factors for N fertilizer and animal manure applied to soils. Key regions in Austria were selected and region specific N2O emissions calculated. The model runs at sub-daily time steps and uses data such as maximum and minimum air temperature, precipitation, radiation, and wind speed as meteorological drivers. Further input data are used to reflect agricultural management practices, e.g., planting/harvesting, tillage, fertilizer application, irrigation and information on soil and vegetation properties for site characterization and model initialization. While at site scale, arable management data (crop cultivation, rotations, timings etc.) is obtained by experimental data from field trials or observations, at regional scale such data need to be generated using region specific proxy data such as land use and management statistics, crop cultivations and yields, crop rotations, fertilizer sales, manure resulting from livestock units etc. The farming

  16. Utility of thermal image sharpening for monitoring field-scale evapotranspiration over rainfed and irrigated agricultural regions

    NASA Astrophysics Data System (ADS)

    Agam, Nurit; Kustas, William P.; Anderson, Martha C.; Li, Fuqin; Colaizzi, Paul D.

    2008-01-01

    The utility of a thermal image sharpening algorithm (TsHARP) in providing fine resolution land surface temperature data to a Two-Source-Model for mapping evapotranspiration (ET) was examined over two agricultural regions in the U.S. One site is in a rainfed corn and soybean production region in central Iowa. The other lies within the Texas High Plains, an irrigated agricultural area. It is concluded that in the absence of fine (sub-field scale) resolution thermal data, TsHARP provides an important tool for monitoring ET over rainfed agricultural areas. In contrast, over irrigated regions, TsHARP applied to kilometer-resolution thermal imagery is unable to provide accurate fine resolution land surface temperature due to significant sub-pixel moisture variations that are not captured in the sharpening procedure. Consequently, reliable estimation of ET and crop stress requires thermal imagery acquired at high spatial resolution, resolving the dominant length-scales of moisture variability present within the landscape.

  17. Use of Field Research Sites to Teach Field Techniques in Graduate Level Soil Physics.

    ERIC Educational Resources Information Center

    Cassel, D. K.

    1986-01-01

    Describes how a field research site provides grauduate soil physics students with practical field-oriented experiences. Explains the structure of the course and the nature of the course's investigations. Assesses the advantages and obstacles associated with the field research technique. (ML)

  18. A site-specific agricultural water requirement and footprint estimator (SPARE:WATER 1.0) for irrigation agriculture

    NASA Astrophysics Data System (ADS)

    Multsch, S.; Al-Rumaikhani, Y. A.; Frede, H.-G.; Breuer, L.

    2013-01-01

    The water footprint accounting method addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). Most of current water footprint assessments focus on global to continental scale. We therefore developed the spatial decision support system SPARE:WATER that allows to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirement and water footprints are assessed on a grid-basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume in-efficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water can be defined as the water to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr-1 for 2008 with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional water footprint assessments.

  19. Soil hydrological and soil property changes resulting from termite activity on agricultural fields in Burkina Faso

    NASA Astrophysics Data System (ADS)

    Mettrop, I.; Cammeraat, L. H.; Verbeeten, E.

    2009-04-01

    Termites are important ecosystem-engineers in subtropical and tropical regions. The effect of termite activity affecting soil infiltration is well documented in the Sahelian region. Most studies find increased infiltration rates on surfaces that are affected by termite activity in comparison to crusted areas showing non-termite presence. Crusted agricultural fields in the Sanmatenga region in Burkina Faso with clear termite activity were compared to control fields without visual ground dwelling termite activity. Fine scale rainfall simulations were carried out on crusted termite affected and control sites. Furthermore soil moisture change, bulk density, soil organic matter as well as general soil characteristics were studied. The top soils in the study area were strongly crusted (structural crust) after the summer rainfall and harvest of millet. They have a loamy sand texture underlain by a shallow sandy loam Bt horizon. The initial soil moisture conditions were significantly higher on the termite plots when compared to control sites. It was found that the amount of runoff produced on the termite plots was significantly higher, and also the volumetric soil moisture content after the experiments was significantly lower if compared to the control plots. Bulk density showed no difference whereas soil organic matter was significantly higher under termite affected areas, in comparison to the control plots. Lab tests showed no significant difference in hydrophobic behavior of the topsoil and crust material. Micro and macro-structural properties of the topsoil did not differ significantly between the termite sites and the control sites. The texture of the top 5 cm of the soil was also found to be not significantly different. The infiltration results are contradictory to the general literature, which reports increased infiltration rates after prolonged termite activity although mostly under different initial conditions. The number of nest entrances was clearly higher in

  20. Use of vegetated agricultural drainage ditches to decrease pesticide transport from tomato and alfalfa fields in California, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation and storm water runoff from agricultural fields has the potential to cause impairment to downstream aquatic receiving systems. Over the last several years, scientists have discovered the benefit of using edge-of-field practices, such as vegetated agricultural drainage ditches, in the mit...

  1. Deriving a per-field land use and land cover map in an agricultural mosaic catchment

    NASA Astrophysics Data System (ADS)

    Seo, B.; Bogner, C.; Poppenborg, P.; Martin, E.; Hoffmeister, M.; Jun, M.; Koellner, T.; Reineking, B.; Shope, C. L.; Tenhunen, J.

    2014-04-01

    Detailed data on land use and land cover constitutes important information for Earth system models, environmental monitoring and ecosystem services research. Global land cover products are evolving rapidly, however, there is still a lack of information particularly for heterogeneous agricultural landscapes. We censused land use and land cover field by field in an agricultural mosaic catchment Haean, South Korea. We recorded the land cover types with additional information on agricultural practice and make this data available at the public repository Pangaea (doi:10.1594/PANGAEA.823677). In this paper we introduce the data, its collection and the post-processing protocol. During the studied period, a large portion of dry fields was converted to perennial crops. A comparison between our dataset and MODIS Land Cover Type (MCD12Q1) suggested that the MODIS product was restricted in this area since it does not distinguish irrigated fields from general croplands. In addition, linear landscape elements such as water bodies were not detected in the MODIS product due to its coarse spatial resolution. The data presented here can be useful for earth science and ecosystem services research.

  2. A mobile app for delivering in-field soil data for precision agriculture

    NASA Astrophysics Data System (ADS)

    Isaacs, John P.; Stojanovic, Vladeta; Falconer, Ruth E.

    2015-04-01

    In the last decade precision agriculture has grown from a concept to an emerging technology, largely due to the maturing of GPS and mobile mapping. We investigated methods for reliable delivery and display of appropriate and context aware in-field farm data on mobile devices by developing a prototype android mobile app. The 3D app was developed using OpenGL ES 2.0 and written in Java, using the Android Development Tools (ADT) SDK. The app is able to obtain GPS coordinates and automatically synchronise the view and load relevant data based on the user's location. The intended audience of the mobile app is farmers and agronomists. Apps are becoming an essential tool in an agricultural professional's arsenal however most existing apps are limited to 2D display of data even though the modern chips in mobile devices can support the display of 3D graphics at interactive rates using technologies such as webGL. This project investigated the use of games techniques in the delivery and 3D display of field data, recognising that this may be a departure from the way the field data is currently delivered and displayed to farmers and agronomists. Different interactive 3D visualisation methods presenting spatial and temporal variation in yield values were developed and tested. It is expected that this app can be used by farmers and agronomists to support decision making in the field of precision agriculture and this is a growing market in UK and Europe.

  3. Long-term monitoring of nitrate transport to drainage from three agricultural clayey till fields

    NASA Astrophysics Data System (ADS)

    Ernstsen, V.; Olsen, P.; Rosenbom, A. E.

    2015-08-01

    The application of nitrogen (N) fertilisers to crops grown on tile-drained fields is required to sustain most modern crop production, but it poses a risk to the aquatic environment since tile drains facilitate rapid transport pathways with no significant reduction in nitrate. To maintain the water quality of the aquatic environment and the provision of food from highly efficient agriculture in line with the EU's Water Framework Directive and Nitrates Directive, field-scale knowledge is essential for introducing water management actions on-field or off-field and producing an optimal differentiated N-regulation in future. This study strives to provide such knowledge by evaluating on 11 years of nitrate-N concentration measurements in drainage from three subsurface-drained clayey till fields (1.3-2.3 ha) representing approximately 71 % of the surface sediments in Denmark dominated by clay. The fields differ in their inherent hydrogeological field settings (e.g. soil-type, geology, climate, drainage and groundwater table) and the agricultural management of the fields (e.g. crop type, type of N fertilisers and agricultural practices). The evaluation revealed three types of clayey till fields characterised by: (i) low net precipitation, high concentration of nitrate-N, and short-term low intensity drainage at air temperatures often below 5 °C; (ii) medium net precipitation, medium concentration of nitrate-N, and short-term medium-intensity drainage at air temperatures often above 5 °C; and (iii) high net precipitation, low concentration of nitrate-N and long-term high intensity drainage at air temperatures above 5 °C. For each type, on-field water management actions, such as the selection of crop types and introduction of catch crops, appeared relevant, whereas off-field actions only seemed relevant for the latter two field types given the temperature-dependent reduction potential of nitrate off-field. This initial well-documented field-scale knowledge from fields

  4. Profiling Nematode Communities in Unmanaged Flowerbed and Agricultural Field Soils in Japan by DNA Barcode Sequencing

    PubMed Central

    Morise, Hisashi; Miyazaki, Erika; Yoshimitsu, Shoko; Eki, Toshihiko

    2012-01-01

    Soil nematodes play crucial roles in the soil food web and are a suitable indicator for assessing soil environments and ecosystems. Previous nematode community analyses based on nematode morphology classification have been shown to be useful for assessing various soil environments. Here we have conducted DNA barcode analysis for soil nematode community analyses in Japanese soils. We isolated nematodes from two different environmental soils of an unmanaged flowerbed and an agricultural field using the improved flotation-sieving method. Small subunit (SSU) rDNA fragments were directly amplified from each of 68 (flowerbed samples) and 48 (field samples) isolated nematodes to determine the nucleotide sequence. Sixteen and thirteen operational taxonomic units (OTUs) were obtained by multiple sequence alignment from the flowerbed and agricultural field nematodes, respectively. All 29 SSU rDNA-derived OTUs (rOTUs) were further mapped onto a phylogenetic tree with 107 known nematode species. Interestingly, the two nematode communities examined were clearly distinct from each other in terms of trophic groups: Animal predators and plant feeders were markedly abundant in the flowerbed soils, in contrast, bacterial feeders were dominantly observed in the agricultural field soils. The data from the flowerbed nematodes suggests a possible food web among two different trophic nematode groups and plants (weeds) in the closed soil environment. Finally, DNA sequences derived from the mitochondrial cytochrome oxidase c subunit 1 (COI) gene were determined as a DNA barcode from 43 agricultural field soil nematodes. These nematodes were assigned to 13 rDNA-derived OTUs, but in the COI gene analysis were assigned to 23 COI gene-derived OTUs (cOTUs), indicating that COI gene-based barcoding may provide higher taxonomic resolution than conventional SSU rDNA-barcoding in soil nematode community analysis. PMID:23284767

  5. Mechanisation of large-scale agricultural fields in developing countries - a review.

    PubMed

    Onwude, Daniel I; Abdulstter, Rafia; Gomes, Chandima; Hashim, Norhashila

    2016-09-01

    Mechanisation of large-scale agricultural fields often requires the application of modern technologies such as mechanical power, automation, control and robotics. These technologies are generally associated with relatively well developed economies. The application of these technologies in some developing countries in Africa and Asia is limited by factors such as technology compatibility with the environment, availability of resources to facilitate the technology adoption, cost of technology purchase, government policies, adequacy of technology and appropriateness in addressing the needs of the population. As a result, many of the available resources have been used inadequately by farmers, who continue to rely mostly on conventional means of agricultural production, using traditional tools and equipment in most cases. This has led to low productivity and high cost of production among others. Therefore this paper attempts to evaluate the application of present day technology and its limitations to the advancement of large-scale mechanisation in developing countries of Africa and Asia. Particular emphasis is given to a general understanding of the various levels of mechanisation, present day technology, its management and application to large-scale agricultural fields. This review also focuses on/gives emphasis to future outlook that will enable a gradual, evolutionary and sustainable technological change. The study concludes that large-scale-agricultural farm mechanisation for sustainable food production in Africa and Asia must be anchored on a coherent strategy based on the actual needs and priorities of the large-scale farmers. © 2016 Society of Chemical Industry. PMID:26940194

  6. Polyoxyethylene Tallow Amine, a Glyphosate Formulation Adjuvant: Soil Adsorption Characteristics, Degradation Profile, and Occurrence on Selected Soils from Agricultural Fields in Iowa, Illinois, Indiana, Kansas, Mississippi, and Missouri.

    PubMed

    Tush, Daniel; Meyer, Michael T

    2016-06-01

    Polyoxyethylene tallow amine (POEA) is an inert ingredient added to formulations of glyphosate, the most widely applied agricultural herbicide. POEA has been shown to have toxic effects to some aquatic organisms making the potential transport of POEA from the application site into the environment an important concern. This study characterized the adsorption of POEA to soils and assessed its occurrence and homologue distribution in agricultural soils from six states. Adsorption experiments of POEA to selected soils showed that POEA adsorbed much stronger than glyphosate; calcium chloride increased the binding of POEA; and the binding of POEA was stronger in low pH conditions. POEA was detected on a soil sample from an agricultural field near Lawrence, Kansas, but with a loss of homologues that contain alkenes. POEA was also detected on soil samples collected between February and early March from corn and soybean fields from ten different sites in five other states (Iowa, Illinois, Indiana, Missouri, Mississippi). This is the first study to characterize the adsorption of POEA to soil, the potential widespread occurrence of POEA on agricultural soils, and the persistence of the POEA homologues on agricultural soils into the following growing season. PMID:27163278

  7. Biodiversity in Organic Farmland - How Does Landscape Context Influence Species Diversity in Organic Vs. Conventional Agricultural Fields?

    NASA Astrophysics Data System (ADS)

    Seufert, V.; Wood, S.; Reid, A.; Gonzalez, A.; Rhemtulla, J.; Ramankutty, N.

    2014-12-01

    The most important current driver of biodiversity loss is the conversion of natural habitats for human land uses, mostly for the purpose of food production. However, by causing this biodiversity loss, food production is eroding the very same ecosystem services (e.g. pollination and soil fertility) that it depends on. We therefore need to adopt more wildlife-friendly agricultural practices that can contribute to preserving biodiversity. Organic farming has been shown to typically host higher biodiversity than conventional farming. But how is the biodiversity benefit of organic management dependent on the landscape context farms are situated in? To implement organic farming as an effective means for protecting biodiversity and enhancing ecosystem services we need to understand better under what conditions organic management is most beneficial for species. We conducted a meta-analysis of the literature to answer this question, compiling the most comprehensive database to date of studies that monitored biodiversity in organic vs. conventional fields. We also collected information about the landscape surrounding these fields from remote sensing products. Our database consists of 348 study sites across North America and Europe. Our analysis shows that organic management can improve biodiversity in agricultural fields substantially. It is especially effective at preserving biodiversity in homogeneous landscapes that are structurally simplified and dominated by either cropland or pasture. In heterogeneous landscapes conventional agriculture might instead already hold high biodiversity, and organic management does not appear to provide as much of a benefit for species richness as in simplified landscapes. Our results suggest that strategies to maintain biodiversity-dependent ecosystem services should include a combination of pristine natural habitats, wildlife-friendly farming systems like organic farming, and high-yielding conventional systems, interspersed in structurally

  8. Abundance of denitrification genes under different peizometer depths in four Irish agricultural groundwater sites.

    PubMed

    Barrett, Maria; Jahangir, Mohammad M R; Lee, Changsoo; Smith, Cindy J; Bhreathnach, Niamh; Collins, Gavin; Richards, Karl G; O'Flaherty, Vincent

    2013-09-01

    This study examined the relationship between the abundance of bacterial denitrifiers in groundwater at four sites, differing with respect to overlaying land management and peizometer depth. Groundwater was sourced from 36 multilevel piezometers, which were installed to target different groundwater zones: (1) subsoil, (2) subsoil to bedrock interface, and (3) bedrock. The gene copy concentrations (GCCs), as gene copies per liter, for bacterial 16S rRNA genes and the denitrifying functional genes, nirK, nirS, and nosZ, were determined using quantitative polymerase chain reaction assays. The results were related to gaseous nitrogen emissions and to the physicochemical properties of the four sites. Overall, nirK and nirS abundance appeared to show no significant correlation to N2O production (P = 0.9989; P = 0.3188); and no significant correlation was observed between nosZ and excess N2 concentrations (P = 0.0793). In the majority of piezometers investigated, the variation of nirK and nirS gene copy concentrations was considered significant (P < 0.0001). Dissolved organic carbon (DOC) decreased with aquifer depth and ranged from 1.0-4.0 mg l(-1), 0.9-2.4 mg l(-1), and 0.8-2.4 mg l(-1) within piezometers located in the subsoil, subsoil/bedrock interface, and bedrock depths, respectively. The availability of increasing DOC and the depth of the water table were positively correlated with increasing nir and nosZ GCCs (P = 0.0012). A significant temporal correlation was noted between nirS and piezometer depth (P < 0.001). Interestingly, the nirK, nirS, and nosZ GCCs varied between piezometer depths within specific sites, while GCCs remained relatively constant from site to site, thus indicating no direct impact of agricultural land management strategies investigated on denitrifier abundance. PMID:23625052

  9. FIELD APPLICATIONS OF ROBOTIC SYSTEMS IN HAZARDOUS WASTE SITE OPERATIONS

    EPA Science Inventory

    The cleanup of hazardous waste sites is a challenging and complex field that offers numerous opportunities for the application of robotic technology. he contamination problem, long in the making, will take decades to resolve. ur ingenuity in developing robotic tools to assist in ...

  10. DENSE GAS PLUME FIELD MEASUREMENTS AT THE NEVADA TEST SITE

    EPA Science Inventory

    Field experiments on dense gas diffusion carried out at the Spills Test Facility on the Nevada Test Site are briefly described, including four "baseline" releases made in July 1993 and two new series planned for August-September 1995. he first series will target neutral to very s...

  11. Multi-Sited Ethnography and the Field of Educational Research

    ERIC Educational Resources Information Center

    Pierides, Dean

    2010-01-01

    This paper responds to the challenge of how educational research might be practised in a contemporary world that is no longer necessarily organised by nearness and unity. Focusing on ethnography, it argues for what a multi-sited imaginary contributes to research in the field of education. By giving prominence to the notion of multi-sited…

  12. Development of the ClearSky smoke dispersion forecast system for agricultural field burning in the Pacific Northwest

    NASA Astrophysics Data System (ADS)

    Jain, Rahul; Vaughan, Joseph; Heitkamp, Kyle; Ramos, Charleston; Claiborn, Candis; Schreuder, Maarten; Schaaf, Mark; Lamb, Brian

    The post-harvest burning of agricultural fields is commonly used to dispose of crop residue and provide other desired services such as pest control. Despite careful regulation of burning, smoke plumes from field burning in the Pacific Northwest commonly degrade air quality, particularly for rural populations. In this paper, ClearSky, a numerical smoke dispersion forecast system for agricultural field burning that was developed to support smoke management in the Inland Pacific Northwest, is described. ClearSky began operation during the summer through fall burn season of 2002 and continues to the present. ClearSky utilizes Mesoscale Meteorological Model version 5 (MM5v3) forecasts from the University of Washington, data on agricultural fields, a web-based user interface for defining burn scenarios, the Lagrangian CALPUFF dispersion model and web-served animations of plume forecasts. The ClearSky system employs a unique hybrid source configuration, which treats the flaming portion of a field as a buoyant line source and the smoldering portion of the field as a buoyant area source. Limited field observations show that this hybrid approach yields reasonable plume rise estimates using source parameters derived from recent field burning emission field studies. The performance of this modeling system was evaluated for 2003 by comparing forecast meteorology against meteorological observations, and comparing model-predicted hourly averaged PM 2.5 concentrations against observations. Examples from this evaluation illustrate that while the ClearSky system can accurately predict PM 2.5 surface concentrations due to field burning, the overall model performance depends strongly on meteorological forecast error. Statistical evaluation of the meteorological forecast at seven surface stations indicates a strong relationship between topographical complexity near the station and absolute wind direction error with wind direction errors increasing from approximately 20° for sites in

  13. Magnetic field survey at PG&E photovoltaic sites

    SciTech Connect

    Chang, G.J.; Jennings, C.

    1994-08-01

    Public awareness has aroused concerns over the possible effects of magnetic fields on human health. While research continues to determine if magnetic fields do, in fact, affect human health, concerned individuals are requesting data on magnetic field sources in their environments to base personal decisions about limiting their exposure to these sources. Timely acceptance and implementation of photovoltaics (PV), particularly for distributed applications such as PV rooftops, windows, and vehicles, may be hampered by the lack of PV magnetic field data. To address this situation, magnetic flux density was measured around equipment at two PVUSA (Photovoltaics for Utility Scale Applications) project sites in Kerman and Davis, California. This report documents the data and compares the PV magnetic fields with published data on more prevalent magnetic field sources. Although not comprehensive, electric and magnetic field (EMF) data taken at PVUSA indicate that 60-Hz magnetic fields (the EMF type of greatest public concern) are significantly less for PV arrays than for household applications. Therefore, given the present EMF research knowledge, PV array EMF may not merit considerable concern. The PV system components exhibiting significant AC magnetic fields are the transformers and power conditioning units (PCUs). However, the AC magnetic fields associated with these components are localized and are not detected at PV system perimeters. Concern about transformer and PCU EMF would apply to several generation and storage technologies.

  14. A GPS Backpack System for Mapping Soil and Crop Parameters in Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Stafford, J. V.; Lebars, J. M.

    Farmers are having to gather increasing amounts of data on their soils and crops. Precision agriculture metre-by-metre is based on a knowledge of the spatial variation of soil and crop parameters across a field. The data has to be spatially located and GPS is an effective way of doing this. A backpack data logging system with GPS position tagging is described which has been designed to aid a fanner in the manual collection of data.

  15. Agricultural PM 10 emissions from cotton field disking in Las Cruces, NM

    NASA Astrophysics Data System (ADS)

    Kasumba, John; Holmén, Britt A.; Hiscox, April; Wang, Junming; Miller, David

    2011-03-01

    Various studies have shown a relationship between elevated levels of inhalable particulate matter (PM) and agricultural practices, especially in the vicinity of agricultural fields. Airborne particle concentrations and meteorological variables were measured during nine agricultural field events on a cotton field in Las Cruces, NM in March 2008. A variety of real-time and integrated PM 10 and total suspended particles (TSP) samplers were used during sampling. The field events were designed to measure particle concentrations at different heights, near (4 m) and far (20-100 m) from a disking tractor. Particle concentrations decreased with increasing distance from the ground for near-source disking events, whereas particle concentrations were almost independent of height for background events. Near-source disking event particle concentrations were 4-7 times higher than those for far-source disking and background events. Near-source disking events had PM 10 emission factors ranging from 78 to 239 mg m -2, while those for far-source disking events ranged from 8 to 89 mg m -2. PM 10 plume heights for near-source disking events were between 4 and 5.7 m, whereas those for far-source disking events were between 12 and 15 m. Meteorological variables were found to influence emission factors, with wind speed showing a nonlinear relationship with emission factors. No clear relationship was found between soil moisture content and emission factors probably because the range of soil moisture was small. Impactor data indicated 10-40% of the total mass of agricultural PM collected was less than 1 μm in diameter for the clay loam soil type. Vertical PM 10 concentration profiles showed maxima at sampling heights between 1 and 2 m above the ground.

  16. Large field excursions from a few site relaxion model

    NASA Astrophysics Data System (ADS)

    Fonseca, N.; de Lima, L.; Machado, C. S.; Matheus, R. D.

    2016-07-01

    Relaxion models are an interesting new avenue to explain the radiative stability of the Standard Model scalar sector. They require very large field excursions, which are difficult to generate in a consistent UV completion and to reconcile with the compact field space of the relaxion. We propose an N -site model which naturally generates the large decay constant needed to address these issues. Our model offers distinct advantages with respect to previous proposals: the construction involves non-Abelian fields, allowing for controlled high-energy behavior and more model building possibilities, both in particle physics and inflationary models, and also admits a continuum limit when the number of sites is large, which may be interpreted as a warped extra dimension.

  17. Assessment of soil erosion and deposition rates in a Moroccan agricultural field using fallout 137Cs and 210Pbex.

    PubMed

    Benmansour, M; Mabit, L; Nouira, A; Moussadek, R; Bouksirate, H; Duchemin, M; Benkdad, A

    2013-01-01

    In Morocco land degradation - mainly caused by soil erosion - is one of the most serious agroenvironmental threats encountered. However, only limited data are available on the actual magnitude of soil erosion. The study site investigated was an agricultural field located in Marchouch (6°42' W, 33° 47' N) at 68 km south east from Rabat. This work demonstrates the potential of the combined use of (137)Cs, (210)Pb(ex) as radioisotopic soil tracers to estimate mid and long term erosion and deposition rates under Mediterranean agricultural areas. The net soil erosion rates obtained were comparable, 14.3 t ha(-1) yr(-1) and 12.1 ha(-1) yr(-1) for (137)Cs and (210)Pb(ex) respectively, resulting in a similar sediment delivery ratio of about 92%. Soil redistribution patterns of the study field were established using a simple spatialisation approach. The resulting maps generated by the use of both radionuclides were similar, indicating that the soil erosion processes has not changed significantly over the last 100 years. Over the previous 10 year period, the additional results provided by the test of the prediction model RUSLE 2 provided results of the same order of magnitude. Based on the (137)Cs dataset established, the contribution of the tillage erosion impact has been evaluated with the Mass Balance Model 3 and compared to the result obtained with the Mass Balance Model 2. The findings highlighted that water erosion is the leading process in this Moroccan cultivated field, tillage erosion under the experimental condition being the main translocation process within the site without a significant and major impact on the net erosion. PMID:22898495

  18. Vegetation Water Content Mapping in a Diverse Agricultural Landscape: National Airborne Field Experiment 2006

    NASA Technical Reports Server (NTRS)

    Cosh, Michael H.; Jing Tao; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2011-01-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE 06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE 06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/sq m. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy. Keywords: Vegetation, field experimentation, thematic mapper, NDWI, agriculture.

  19. Rapid Assessment of Ecosystem Services Provided by Two Mineral Extraction Sites Restored for Nature Conservation in an Agricultural Landscape in Eastern England

    PubMed Central

    Blaen, Phillip J.; Jia, Li; Peh, Kelvin S.-H.; Field, Rob H.; Balmford, Andrew; MacDonald, Michael A.; Bradbury, Richard B.

    2015-01-01

    Despite growing recognition that mineral sites restored for nature conservation can enhance local biodiversity, the wider societal benefits provided by this type of restoration relative to alternative options are not well understood. This study addresses this research gap by quantifying differences in ecosystem services provision under two common mineral site after-uses: nature conservation and agriculture. Using a combination of site-specific primary field data, benefits transfer and modelling, we show that for our sites restoration for nature conservation provides a more diverse array of ecosystem services than would be delivered under an agricultural restoration scenario. We also explore the effects of addressing different conservation targets, which we find alter the provision of ecosystem services on a service-specific basis. Highly species-focused intervention areas are associated with increased carbon storage and livestock grazing provision, whereas non-intervention areas are important for carbon sequestration, fishing, recreation and flood risk mitigation. The results of this study highlight the wider societal importance of restored mineral sites and may help conservation managers and planners to develop future restoration strategies that provide benefits for both biodiversity and human well-being. PMID:25894293

  20. Rapid assessment of ecosystem services provided by two mineral extraction sites restored for nature conservation in an agricultural landscape in eastern England.

    PubMed

    Blaen, Phillip J; Jia, Li; Peh, Kelvin S-H; Field, Rob H; Balmford, Andrew; MacDonald, Michael A; Bradbury, Richard B

    2015-01-01

    Despite growing recognition that mineral sites restored for nature conservation can enhance local biodiversity, the wider societal benefits provided by this type of restoration relative to alternative options are not well understood. This study addresses this research gap by quantifying differences in ecosystem services provision under two common mineral site after-uses: nature conservation and agriculture. Using a combination of site-specific primary field data, benefits transfer and modelling, we show that for our sites restoration for nature conservation provides a more diverse array of ecosystem services than would be delivered under an agricultural restoration scenario. We also explore the effects of addressing different conservation targets, which we find alter the provision of ecosystem services on a service-specific basis. Highly species-focused intervention areas are associated with increased carbon storage and livestock grazing provision, whereas non-intervention areas are important for carbon sequestration, fishing, recreation and flood risk mitigation. The results of this study highlight the wider societal importance of restored mineral sites and may help conservation managers and planners to develop future restoration strategies that provide benefits for both biodiversity and human well-being. PMID:25894293

  1. Net carbon balance of three full crop rotations at an agricultural site near Gebesee, Germany

    NASA Astrophysics Data System (ADS)

    Hurkuck, M.; Brümmer, C.; Kolle, O.; Kutsch, W. L.; Moffat, A. M.; Mukwashi, K.; Truckenbrodt, S. C.; Herbst, M.

    2015-12-01

    Continuous eddy-covariance (EC) measurements of biosphere-atmosphere CO2 and H2O exchange have been conducted since 2001 at an agricultural site near Gebesee, Germany, thus providing one of the longest EC time series of European croplands. During the experimental period, winter wheat and winter barley were alternately planted with potatoes, sugar beet, rape, and peppermint covering three full crop rotations (2001-2004, 2005-2009, and 2010-2014). In this study, data of 14 years of net ecosystem CO2 exchange (NEE) and evapotranspiration (E) were re-calculated. Based on these data, we present the net carbon (C) balance (net biome production, NBP) accounting for any additional C input by fertilization and C output by harvest. Further emphasis was placed on the sensitivity of water use efficiency (WUE) and E to climate and crop type. The main aim was to investigate the interannual variability in both NBP and WUE, thus disentangling the impacts of climatic conditions and land management on the net C balance as well as on WUE and E.

  2. Identifying Landscape Areas Prone to Generating Storm Runoff in Central New York Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Hofmeister, K.; Walter, M. T.

    2015-12-01

    Nonpoint source (NPS) pollution continues to be a leading cause of surface water degradation, especially in agricultural areas. In humid regions where variable source area (VSA) hydrology dominates storm runoff, NPS pollution is generated where VSAs coincide with polluting activities. Mapping storm runoff risks could allow for more precise and informed targeting of NPS pollution mitigation practices in agricultural landscapes. Topographic wetness indices (TWI) provide good approximations of relative soil moisture patterns and relative storm runoff risks. Simulation models are typically used in conjunction with TWIs to quantify VSA behavior. In this study we use empirically derived relationships between TWI values, volumetric water content (VWC) and rainfall frequencies to develop runoff probability maps. Rainfall and soil VWC were measured across regionally representative agricultural areas in central New York over three years (2012-2015) to determine the volume of runoff generated from agricultural fields in the area. We assumed the threshold for storm runoff occurs when the combination of antecedent soil water and rainfall are sufficient to saturate the soil. We determined that approximately 50% of the storm runoff volume is generated from 10% of the land area during spring, summer, and autumn seasons, while the risk of storm runoff generation is higher in the spring and autumn seasons than in the summer for the same area of land.

  3. Field site selection: getting it right first time around.

    PubMed

    Malcolm, Colin A; El Sayed, Badria; Babiker, Ahmed; Girod, Romain; Fontenille, Didier; Knols, Bart G J; Nugud, Abdel Hameed; Benedict, Mark Q

    2009-01-01

    The selection of suitable field sites for integrated control of Anopheles mosquitoes using the sterile insect technique (SIT) requires consideration of the full gamut of factors facing most proposed control strategies, but four criteria identify an ideal site: 1) a single malaria vector, 2) an unstructured, relatively low density target population, 3) isolation of the target population and 4) actual or potential malaria incidence. Such a site can exist in a diverse range of situations or can be created. Two contrasting SIT field sites are examined here: the desert-flanked Dongola Reach of the Nile River in Northern State, Sudan, where malaria is endemic, and the island of La Reunion, where autochthonous malaria is rare but risk is persistent. The single malaria-transmitting vector at both sites is Anopheles arabiensis. In Sudan, the target area is a narrow 500 km corridor stretching from the rocky terrain at the Fourth Cataract--just above the new Merowe Dam, to the northernmost edge of the species range, close to Egypt. Vector distribution and temporal changes in density depend on the Nile level, ambient temperature and human activities. On La Reunion, the An. arabiensis population is coastal, limited and divided into three areas by altitude and exposure to the trade winds on the east coast. Mosquito vectors for other diseases are an issue at both sites, but of primary importance on La Reunion due to the recent chikungunya epidemic. The similarities and differences between these two sites in terms of suitability are discussed in the context of area-wide integrated vector management incorporating the SIT. PMID:19917079

  4. Field site selection: getting it right first time around

    PubMed Central

    Malcolm, Colin A; El Sayed, Badria; Babiker, Ahmed; Girod, Romain; Fontenille, Didier; Knols, Bart GJ; Nugud, Abdel Hameed; Benedict, Mark Q

    2009-01-01

    The selection of suitable field sites for integrated control of Anopheles mosquitoes using the sterile insect technique (SIT) requires consideration of the full gamut of factors facing most proposed control strategies, but four criteria identify an ideal site: 1) a single malaria vector, 2) an unstructured, relatively low density target population, 3) isolation of the target population and 4) actual or potential malaria incidence. Such a site can exist in a diverse range of situations or can be created. Two contrasting SIT field sites are examined here: the desert-flanked Dongola Reach of the Nile River in Northern State, Sudan, where malaria is endemic, and the island of La Reunion, where autochthonous malaria is rare but risk is persistent. The single malaria-transmitting vector at both sites is Anopheles arabiensis. In Sudan, the target area is a narrow 500 km corridor stretching from the rocky terrain at the Fourth Cataract - just above the new Merowe Dam, to the northernmost edge of the species range, close to Egypt. Vector distribution and temporal changes in density depend on the Nile level, ambient temperature and human activities. On La Reunion, the An. arabiensis population is coastal, limited and divided into three areas by altitude and exposure to the trade winds on the east coast. Mosquito vectors for other diseases are an issue at both sites, but of primary importance on La Reunion due to the recent chikungunya epidemic. The similarities and differences between these two sites in terms of suitability are discussed in the context of area-wide integrated vector management incorporating the SIT. PMID:19917079

  5. Pre-Columbian Agriculture: Construction history of raised fields in Bermeo, in the Bolivian Lowlands

    NASA Astrophysics Data System (ADS)

    Rodrigues, Leonor; Fehr, Seraina; Lombardo, Umberto; Veit, Heinz

    2013-04-01

    Since the beginning of the 1960s, research in the Amazon has revealed that in Pre-Columbian times, landscapes that were viewed as challenging living environments were nevertheless altered in several ways. Raised fields agriculture is one of the most impressive phenomena that can be found in South-eastern Amazonia. Pre-Columbian raised fields are earth platforms of differing shape and dimension that are elevated above the landscape's natural surface. The Llanos de Moxos, situated in the Bolivian Lowlands is one of the areas with the highest density of raised fields. In spite of the high interest in raised field agriculture, very few field-based investigations have been performed. As a result, there remains little explanation as to how they were constructed, managed or for what time frame they were in use. Recently, more detailed investigations have been performed on raised fields located in the indigenous community of Bermeo, in the vicinity of San Ignacio de Moxos. Combined data from fieldwork and laboratory analysis including particle size distribution, thin section micromorphology and radiocarbon analyses as well as optically stimulated luminescence analysis has given an insight into the history of their construction. Applied to the Bolivian Lowlands, the current study provides for the first time data showing aspects of the Pre-Columbian management of the raised fields, and a chronological sequence of utilization and abandonment of these fields. Radiocarbon dating has shown that the raised fields had been in use since as early as 900 AD. Two distinct paleosols identified in the field sequence point to the existence of two separate prolonged soil formation periods. The paleosols are characterized by initial stages of Bt-horizons. Each soil sequence indicates therefore a particular stable period of the field during which no new earth was heaped up. This suggests that contrary to the well supported theory that raised fields were managed through continuous

  6. Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Sites, 1993

    SciTech Connect

    None, None

    1994-10-21

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2,668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling environmental remediation, i.e., the U.S. DOE, the Nuclear Regulatory Commission (NRC), and the California State Department of Health Services (DHS) Radiologic Health Branch (RHB). For that reason, information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major area of interest is radiological, this report also includes a discussion of nonoradiological monitoring at SSFL.

  7. Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Site, 1991

    SciTech Connect

    none,

    1992-12-03

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2.668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling operations with nuclear fuel or nuclear reactors. i.e., the U.S. DOE and the California State Department of Health Services (DHS). Radiologic Health Branch (RHB). For that reason. information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major area of interest is radiological, this report also includes a discussion of nonradiological monitoring at SSFL.

  8. Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Sites, 1992

    SciTech Connect

    none,

    1993-12-14

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2,668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling environmental remediation, i.e., the U.S. DOE, the Nuclear Regulatory Commission (NRC), and the California State Department of Health Services (DHS) Radiologic Health Branch (RHB). For that reason, information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major area of interest is radiological, this report also includes a discussion of nonradiological monitoring at SSFL.

  9. A comparison of rating and dating techniques to estimate the threat of soil erosion to archaeological monuments under agricultural fields

    NASA Astrophysics Data System (ADS)

    van Soest, Maud; Huisman, Hans; Schoorl, Jeroen; Reimann, Tony; Temme, Arnaud; Wallinga, Jakob; de Kort, Jan-Willem; van der Heiden, Menno; van Os, Bertil; van Egmond, Fenny; Ketteren, Michael

    2015-04-01

    For the protection of Dutch archaeological sites against degradation, the TOPsites project is investigating the rate, extent and mitigation of the most important processes involved. One of these processes is soil translocation or soil redistribution. For many Dutch archaeological sites the actual extent and rate of soil erosion is not yet known. In this study different techniques for dating and estimating rates have been compared on three archaeological sites on tilled fields with gentle slopes: (multi-temporal LiDar, profiles and spatial distribution of 137Cs, anthropogenic Pb, and 239+240Pu, and moreover OSL. In addition, the added value of the combination of several of these techniques together will be evaluated. Preliminary results show evidence for colluvium formation (deposition) on two of the sites. Lead contents in a buried soil on one of these sites suggest a subrecent to recent date. 137Cs profiles and spatial mapping, however, do not show clear evidence for recent erosion or re-deposition patterns. These first results suggest that in these agricultural settings with typical Dutch gentle slopes, erosion may only occur in rare, catastrophic, events with local high erosion and re-deposition rates instead of a more or less continuous process with lower rates. Consequently, the impact of ploughing might be limited to mixing of the plough layer, while the effect of damaging soil translocation, for these selected archaeological sites, seems less important. Forthcoming analysis and results of Pu and OSL will provide enough data for further discussion and possible falsification of these preliminary conclusions.

  10. Multiple routes of pesticide exposure for honey bees living near agricultural fields.

    PubMed

    Krupke, Christian H; Hunt, Greg J; Eitzer, Brian D; Andino, Gladys; Given, Krispn

    2012-01-01

    Populations of honey bees and other pollinators have declined worldwide in recent years. A variety of stressors have been implicated as potential causes, including agricultural pesticides. Neonicotinoid insecticides, which are widely used and highly toxic to honey bees, have been found in previous analyses of honey bee pollen and comb material. However, the routes of exposure have remained largely undefined. We used LC/MS-MS to analyze samples of honey bees, pollen stored in the hive and several potential exposure routes associated with plantings of neonicotinoid treated maize. Our results demonstrate that bees are exposed to these compounds and several other agricultural pesticides in several ways throughout the foraging period. During spring, extremely high levels of clothianidin and thiamethoxam were found in planter exhaust material produced during the planting of treated maize seed. We also found neonicotinoids in the soil of each field we sampled, including unplanted fields. Plants visited by foraging bees (dandelions) growing near these fields were found to contain neonicotinoids as well. This indicates deposition of neonicotinoids on the flowers, uptake by the root system, or both. Dead bees collected near hive entrances during the spring sampling period were found to contain clothianidin as well, although whether exposure was oral (consuming pollen) or by contact (soil/planter dust) is unclear. We also detected the insecticide clothianidin in pollen collected by bees and stored in the hive. When maize plants in our field reached anthesis, maize pollen from treated seed was found to contain clothianidin and other pesticides; and honey bees in our study readily collected maize pollen. These findings clarify some of the mechanisms by which honey bees may be exposed to agricultural pesticides throughout the growing season. These results have implications for a wide range of large-scale annual cropping systems that utilize neonicotinoid seed treatments. PMID

  11. Operation of agricultural test fields for study of stressed crops by remote sensing

    NASA Technical Reports Server (NTRS)

    Toler, R. W.

    1974-01-01

    A test site for the study of winter wheat development and collection of ERTS data was established in September of 1973. The test site is a 10 mile square area located 12.5 miles west of Amarillo, Texas on Interstate Hwy. 40, in Randall and Potter counties. The center of the area is the Southwestern Great Plains Research Center at Bushland, Texas. Within the test area all wheat fields were identified by ground truth and designated irrigated or dryland. The fields in the test area other than wheat were identified as to pasture or the crop that was grown. A ground truth area of hard red winter wheat was established west of Hale Center, Texas. Maps showing the location of winter wheat fields in excess of 40 acres in size within a 10 mile radius were supplied NASA. Satellite data was collected for this test site (ERTS-1).

  12. Ca. Nitrososphaera and Bradyrhizobium are inversely correlated and related to agricultural practices in long-term field experiments.

    PubMed

    Zhalnina, Kateryna; de Quadros, Patricia D; Gano, Kelsey A; Davis-Richardson, Austin; Fagen, Jennie R; Brown, Christopher T; Giongo, Adriana; Drew, Jennifer C; Sayavedra-Soto, Luis A; Arp, Dan J; Camargo, Flavio A O; Daroub, Samira H; Clark, Ian M; McGrath, Steve P; Hirsch, Penny R; Triplett, Eric W

    2013-01-01

    Agricultural land management, such as fertilization, liming, and tillage affects soil properties, including pH, organic matter content, nitrification rates, and the microbial community. Three different study sites were used to identify microorganisms that correlate with agricultural land use and to determine which factors regulate the relative abundance of the microbial signatures of the agricultural land-use. The three sites included in this study are the Broadbalk Experiment at Rothamsted Research, UK, the Everglades Agricultural Area, Florida, USA, and the Kellogg Biological Station, Michigan, USA. The effects of agricultural management on the abundance and diversity of bacteria and archaea were determined using high throughput, barcoded 16S rRNA sequencing. In addition, the relative abundance of these organisms was correlated with soil features. Two groups of microorganisms involved in nitrogen cycle were highly correlated with land use at all three sites. The ammonia oxidizing-archaea, dominated by Ca. Nitrososphaera, were positively correlated with agriculture while a ubiquitous group of soil bacteria closely related to the diazotrophic symbiont, Bradyrhizobium, was negatively correlated with agricultural management. Analysis of successional plots showed that the abundance of ammonia oxidizing-archaea declined and the abundance of bradyrhizobia increased with time away from agriculture. This observation suggests that the effect of agriculture on the relative abundance of these genera is reversible. Soil pH and NH3 concentrations were positively correlated with archaeal abundance but negatively correlated with the abundance of Bradyrhizobium. The high correlations of Ca. Nitrososphaera and Bradyrhizobium abundances with agricultural management at three long-term experiments with different edaphoclimatic conditions allowed us to suggest these two genera as signature microorganisms for agricultural land use. PMID:23641242

  13. Ca. Nitrososphaera and Bradyrhizobium are inversely correlated and related to agricultural practices in long-term field experiments

    PubMed Central

    Zhalnina, Kateryna; de Quadros, Patricia D.; Gano, Kelsey A.; Davis-Richardson, Austin; Fagen, Jennie R.; Brown, Christopher T.; Giongo, Adriana; Drew, Jennifer C.; Sayavedra-Soto, Luis A.; Arp, Dan J.; Camargo, Flavio A. O.; Daroub, Samira H.; Clark, Ian M.; McGrath, Steve P.; Hirsch, Penny R.; Triplett, Eric W.

    2013-01-01

    Agricultural land management, such as fertilization, liming, and tillage affects soil properties, including pH, organic matter content, nitrification rates, and the microbial community. Three different study sites were used to identify microorganisms that correlate with agricultural land use and to determine which factors regulate the relative abundance of the microbial signatures of the agricultural land-use. The three sites included in this study are the Broadbalk Experiment at Rothamsted Research, UK, the Everglades Agricultural Area, Florida, USA, and the Kellogg Biological Station, Michigan, USA. The effects of agricultural management on the abundance and diversity of bacteria and archaea were determined using high throughput, barcoded 16S rRNA sequencing. In addition, the relative abundance of these organisms was correlated with soil features. Two groups of microorganisms involved in nitrogen cycle were highly correlated with land use at all three sites. The ammonia oxidizing-archaea, dominated by Ca. Nitrososphaera, were positively correlated with agriculture while a ubiquitous group of soil bacteria closely related to the diazotrophic symbiont, Bradyrhizobium, was negatively correlated with agricultural management. Analysis of successional plots showed that the abundance of ammonia oxidizing-archaea declined and the abundance of bradyrhizobia increased with time away from agriculture. This observation suggests that the effect of agriculture on the relative abundance of these genera is reversible. Soil pH and NH3 concentrations were positively correlated with archaeal abundance but negatively correlated with the abundance of Bradyrhizobium. The high correlations of Ca. Nitrososphaera and Bradyrhizobium abundances with agricultural management at three long-term experiments with different edaphoclimatic conditions allowed us to suggest these two genera as signature microorganisms for agricultural land use. PMID:23641242

  14. Edge-of-field research to quantify the impacts of agricultural practices on water quality in Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage is needed to sustain agricultural production to meet the demands of a growing global population, but it also transports nutrients from fields to surface water bodies. The State of Ohio is facing the tremendous challenge of maintaining agricultural production while protecting the environment...

  15. Dispersion characteristics and sinks for methyl bromide vapors downwind of treated agricultural fields

    SciTech Connect

    Seiber, J.N.; Woodrow, J.E.; Dowling, K.

    1995-12-31

    A study of methyl bromide volatilization and fate from a treated agricultural field was conducted in Monterey County, California, in 1994. Air concentrations were measured above and downwind from the field with the objective of comparing vertical and horizontal flux terms. Another objective was to compare observed downwind concentrations with those predicted by the Industrial Source Complex model, to begin the process of identifying potential sinks which might scavenge methyl bromide from the atmosphere. The final objective was to determine the limit of detection of our analytical method for airborne methyl bromide using field samples representing a wide range of concentrations. A description of the methods and results of the study will be presented, along with a discussion of data quality and interpretation.

  16. Preparing students for higher education and careers in agriculture and related fields: An ethnography of an urban charter school

    NASA Astrophysics Data System (ADS)

    Henry, Kesha Atasha

    This study explored the preparation of students for higher education and careers in agriculturally-related fields at an urban charter high school. The data were collected through interviews, observations, and field notes. The data were analyzed by qualitative methodology with phenomenology as the theoretical framework. Findings indicated that administrators thought it was important to incorporate agricultural science courses into urban school curricula. They stated that agricultural science courses gave urban students a different way of looking at science and helped to enhance the science and technology focus of the school. Further, agricultural science courses helped to break urban students' stereotypes about agriculture and helped to bring in more state funding for educational programs. However they thought that it was more challenging to teach agricultural science in urban versus rural schools and they focused more on Science, Technology, Engineering, and Mathematics (STEM) related careers. The students had mixed views about higher education and careers in agriculture. This was based on their limited knowledge and stereotypes about agricultural majors and career options. The students highlighted several key reasons why they chose to enroll in agricultural science courses. This included the benefits of dual science credits and the ability to earn an associate degree upon successful completion of their program. Students also loved science and appreciated the science intensive nature of the agricultural courses. Additionally, they thought that the agricultural science courses were better than the other optional courses. The results also showed that electronic media such as radio and TV had a negative impact on students' perceptions about higher education and careers in agriculturally-related fields. Conclusions and recommendations are presented.

  17. Influence of a riparian wetland on nitrate and herbicides exported from an agricultural field.

    PubMed

    Angier, Jonathan T; McCarty, Gregory W; Rice, Clifford P; Bialek, Krystyna

    2002-07-17

    Agrochemicals are a major source of nonpoint pollution. Forested corridors along stream channels (riparian zones) are thought to be potential sites for removal of agricultural contaminants from ground and surface waters. First-order riparian wetlands are reputed to be especially effective at groundwater remediation. The study site is a fairly typical (for eastern Maryland) small, first-order stream in an agricultural watershed. Preferential flow supplies most of the stream water within the riparian headwater wetland. This upstream area also contains the highest average stream N and pesticide loads in the entire first-order riparian system. Zones of active groundwater emergence onto the surface display high concentrations of nitrate throughout the soil profile and in the exfiltrating water, whereas inactive areas (where there is no visible upwelling) show rapid attenuation of nitrate with decreasing depths. Atrazine degradation products appear to penetrate more readily through the most active upwelling zones, and there is a correlation between zones of high nitrate and high atrazine metabolite levels. Deethylatrazine/atrazine ratios (DAR) seem to indicate that stream flow is dominated by ground water and that much of the ground water may have reached the stream via preferential flow. Remediative processes appear to be very complex, heterogeneous, and variable in these systems, so additional research is needed before effective formulation and application of riparian zone initiatives and guidelines can be accomplished. PMID:12105980

  18. Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Sites, 1994

    SciTech Connect

    none,

    1995-09-30

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation (Rocketdyne). These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2.668 acres), warrants comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring of DOE-sponsored activities to the regulatory agencies. i.e., the U.S. DOE, the Nuclear Regulatory Commission (NRC), and the California State Department of Health Services (DHS) Radiologic Health Branch (RHB). For that reason, information concentrates on Area IV at SSFL. which is the only area where DOE activities have been performed. While the major focus of attention is radiological, this report also includes a discussion of nonradiological monitoring at SSFL.

  19. Rocketdyne Division annual site environmental report Santa Susana Field Laboratory and Desoto sites 1995

    SciTech Connect

    1996-07-30

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation (Rocketdyne). These are identified as the Santa Susana Field Laboratory (SSFL) and the DeSoto site. The sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The DeSoto site essentially comprises office space and light industry with no remaining radiological operations, and has little potential impact on the environment. The SSFL site, because of its large size (2,668 acres), warrants comprehensive monitoring to assure protection of the environment. SSFL consists of four administrative areas used for research, development, and test operations as well as a buffer zone. A portion of Area I and all of Area II are owned by the U.S. Government and assigned to the National Aeronautics and Space Administration (NASA). A portion of Area IV is under option for purchase by the Department of Energy (DOE).

  20. Hydrological and erosion processes in terraced agricultural fields: observations from a wet Mediterranean region in northern Portugal

    NASA Astrophysics Data System (ADS)

    Nunes, João Pedro; Bernard-Jannin, Léonard; Rodriguez-Blanco, María Luz; Marisa Santos, Juliana; Oliveira Alves Coelho, Celeste; Keizer, Jan Jacob

    2015-04-01

    Traditional agriculture in the mountainous humid regions of the northwestern Iberian peninsula has relied on terraces for soil retention. In the last decades, a strong afforestation (in many cases with commercial species) has led to the appearance of large forest areas coexisting with traditional agricultural landscapes. Soil erosion research in this region has therefore focused on the impact of forest management practices and associated disturbances such as wildfires. However, there has been little research on the impacts of traditional terracing practices on erosion, and therefore it has been difficult to connect forest research with the wider issue of sediment connectivity in this complex agroforestry landscape. This work tried to address this research gap by monitoring an agricultural terrace in the Caramulo mountains, northern Portugal, during two years. The field site is located in a humid Mediterranean climate region, with c. 1500 mm/y rainfall, overlaying granite bedrock; agricultural practices are a traditional rotation between winter pasture and summer (irrigated) corn cultivation. During this period, the soil properties of the terrace were characterized, and there was a continuous monitoring of rainfall, soil moisture and surface runoff at the outlet, as well as 1 or 2-weekly collections of runoff to measure sediment yield. Occasional measurements of vegetation cover and erosion features (rills) within the plot were also made. Preliminary results indicate that runoff generation occurred mostly due to saturation-excess, possibly linked with the accumulation of groundwater in the lower layers of the soil. After one of the largest events, there was a clear inflow of runoff from outside the terrace, through either the irrigation network linking all terraces or by resurfacing of groundwater. Sediment yield was linked with runoff, but sediment concentration was linked with vegetation cover and was highest during the early stages of pasture growth. However

  1. The Role Of Management Of The Field-Forest Boundary In Poland's Process Of Agricultural Restructuring

    NASA Astrophysics Data System (ADS)

    Woch, Franciszek; Borek, Robert

    2015-01-01

    The aim of the work described here has been to point to the relationships between the field-forest boundary and crop productivity as regards the present agrarian land-use structure in Poland, and to provide new opportunities for arranging the agrarian process and the spatial planning of the rural landscape in the context of the sustainable shaping of the field-forest boundary. Impacts of forests and woodlands on crop productivity have been assessed using available data from relevant Polish literature. An assessment of the plot-distribution pattern characterising farms in Poland was made on the basis of reference data from the Agency for the Restructuring and Modernisation of Agriculture. Finally, the possibility of afforestation of agricultural land has been evaluated within the existing legal framework, and on the basis of available data, with attention paid to the need to include organization of the field-forest boundary within the comprehensive management and planning of rural areas, and to preserve woody elements in patchy landscapes. This all creates an opportunity to test innovative approaches to integrated land use which combines the creation of public goods and local products based on participatory learning processes that bring in local stakeholders and decision-makers.

  2. Integrated analysis of root microbiomes of soybean and wheat from agricultural fields

    PubMed Central

    Rascovan, Nicolás; Carbonetto, Belén; Perrig, Diego; Díaz, Marisa; Canciani, Wilter; Abalo, Matías; Alloati, Julieta; González-Anta, Gustavo; Vazquez, Martín P.

    2016-01-01

    Root associated bacteria are critical for plant growth and health. Understanding the composition and role of root microbiota is crucial toward agricultural practices that are less dependent on chemical fertilization, which has known negative effects on the environment and human health. Here we analyzed the root-associated microbiomes of soybean and wheat under agricultural field conditions. We took samples from 11 different production fields across a large geographic area. We used 16S rRNA pyrosequencing to explore root microbial communities and also obtained 2,007 bacterial isolates from rhizospheres, which were tested for the presence of plant growth promoting (PGP) traits in-vitro. We observed that pH and nitrate content correlated with beta diversity variability of rhizospheric bacterial communities despite the variable field conditions. We described the dominant bacterial groups associated to roots from both crops at a large geographic scale and we found that a high proportion of them (60–70%) showed more than 97% similarity to bacteria from the isolated collection. Moreover, we observed that 55% of the screened isolates presented PGP activities in vitro. These results are a significant step forward in understanding crop-associated microbiomes and suggest that new directions can be taken to promote crop growth and health by modulating root microbiomes. PMID:27312589

  3. Integrated analysis of root microbiomes of soybean and wheat from agricultural fields.

    PubMed

    Rascovan, Nicolás; Carbonetto, Belén; Perrig, Diego; Díaz, Marisa; Canciani, Wilter; Abalo, Matías; Alloati, Julieta; González-Anta, Gustavo; Vazquez, Martín P

    2016-01-01

    Root associated bacteria are critical for plant growth and health. Understanding the composition and role of root microbiota is crucial toward agricultural practices that are less dependent on chemical fertilization, which has known negative effects on the environment and human health. Here we analyzed the root-associated microbiomes of soybean and wheat under agricultural field conditions. We took samples from 11 different production fields across a large geographic area. We used 16S rRNA pyrosequencing to explore root microbial communities and also obtained 2,007 bacterial isolates from rhizospheres, which were tested for the presence of plant growth promoting (PGP) traits in-vitro. We observed that pH and nitrate content correlated with beta diversity variability of rhizospheric bacterial communities despite the variable field conditions. We described the dominant bacterial groups associated to roots from both crops at a large geographic scale and we found that a high proportion of them (60-70%) showed more than 97% similarity to bacteria from the isolated collection. Moreover, we observed that 55% of the screened isolates presented PGP activities in vitro. These results are a significant step forward in understanding crop-associated microbiomes and suggest that new directions can be taken to promote crop growth and health by modulating root microbiomes. PMID:27312589

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

    NASA Technical Reports Server (NTRS)

    Bauer, M. E.; Vanderbilt, V. C.; Robinson, B. F.; Daughtry, C. S. T.

    1980-01-01

    It is pointed out that in order to develop the full potential of multispectral measurements acquired from satellite or aircraft sensors to monitor, map, and inventory agricultural resources, increased knowledge and understanding of the spectral properties of crops and soils are needed. The present state of knowledge is reviewed, emphasizing current investigations of the multispectral reflectance characteristics of crops and soils as measured from laboratory, field, aerial, and satellite sensor systems. The relationships of important biological and physical characteristics to their spectral properties of crops and soils are discussed. Future research needs are also indicated.

  5. The radiocaesium interception potential (RIP) at an agricultural site in Germany.

    PubMed

    Schimmack, W; Auerswald, K

    2004-01-01

    Erosion and accumulation sites differ in the amount of fallout 137Cs due to its particulate translocation together with the soil. To examine whether these sites differ also in the radiocaesium interception potential (RIP) of the soil, the RIP of the plough horizon and the first layer of the B horizon was determined at 60 nodes of a 25 m x 25 m grid of a field in Scheyern, Germany, where erosion has been observed in earlier studies (e.g. J. Environ. Radioact. 53 (2001) 41). Upslope of the slope inflection point, the RIP values in the Ap and B horizons were significantly greater than downslope. Moreover, the RIP of the Ap horizon was positively correlated with the elevation a.s.l. of the points indicating an effect of erosion processes on the RIP. This assumption was supported by the soil morphology and the highly significant correlation of the RIP with soil erosion rates determined earlier by radiotracer quantification [Naturwissenschaften 89 (2002) 43] if four of 31 soil erosion points located close together were omitted. These results indicate that erosion not only modifies the pattern of fallout Cs but also the pattern of RIP. PMID:15312700

  6. CHEMICAL AND BIOLOGICAL CHARACTERIZATION OF PRODUCTS OF INCOMPLETE COMBUSTION FROM THE SIMULATED FIELD BURNING OF AGRICULTURAL PLASTIC

    EPA Science Inventory

    The article describes chemical and biological analyses performed to characterize products of incomplete combustion emitted during the simulated open field burning of agricultural plastic. The study highlights the benefits of a combined chemical/biological approach to characteizin...

  7. Detection of Binding Site Molecular Interaction Field Similarities.

    PubMed

    Chartier, Matthieu; Najmanovich, Rafael

    2015-08-24

    Protein binding-site similarity detection methods can be used to predict protein function and understand molecular recognition, as a tool in drug design for drug repurposing and polypharmacology, and for the prediction of the molecular determinants of drug toxicity. Here, we present IsoMIF, a method able to identify binding site molecular interaction field similarities across protein families. IsoMIF utilizes six chemical probes and the detection of subgraph isomorphisms to identify geometrically and chemically equivalent sections of protein cavity pairs. The method is validated using six distinct data sets, four of those previously used in the validation of other methods. The mean area under the receiver operator curve (AUC) obtained across data sets for IsoMIF is higher than those of other methods. Furthermore, while IsoMIF obtains consistently high AUC values across data sets, other methods perform more erratically across data sets. IsoMIF can be used to predict function from structure, to detect potential cross-reactivity or polypharmacology targets, and to help suggest bioisosteric replacements to known binding molecules. Given that IsoMIF detects spatial patterns of molecular interaction field similarities, its predictions are directly related to pharmacophores and may be readily translated into modeling decisions in structure-based drug design. IsoMIF may in principle detect similar binding sites with distinct amino acid arrangements that lead to equivalent interactions within the cavity. The source code to calculate and visualize MIFs and MIF similarities are freely available. PMID:26158641

  8. Site Characterization for a Deep Borehole Field Test

    NASA Astrophysics Data System (ADS)

    Kuhlman, K. L.; Hardin, E. L.; Freeze, G. A.; Sassani, D.; Brady, P. V.

    2015-12-01

    The US Department of Energy Office of Nuclear Energy is at the beginning of 5-year Deep Borehole Field Test (DBFT) to investigate the feasibility of constructing and characterizing two boreholes in crystalline basement rock to a depth of 5 km (16,400 ft). The concept of deep borehole disposal for radioactive waste has some advantages over mined repositories, including incremental construction and loading, the enhanced natural barriers provided by deep continental crystalline basement, and reduced site characterization. Site characterization efforts need to determine an eligible site that does not have the following disqualifying characteristics: greater than 2 km to crystalline basement, upward vertical fluid potential gradients, presence of economically exploitable natural resources, presence of high permeability connection to the shallow subsurface, and significant probability of future seismic or volcanic activity. Site characterization activities for the DBFT will include geomechanical (i.e., rock in situ stress state, and fluid pressure), geological (i.e., rock and fracture infill lithology), hydrological (i.e., quantity of fluid, fluid convection properties, and solute transport mechanisms), and geochemical (i.e., rock-water interaction and natural tracers) aspects. Both direct (i.e., sampling and in situ testing) and indirect (i.e., borehole geophysical) methods are planned for efficient and effective characterization of these site aspects and physical processes. Borehole-based characterization will be used to determine the variability of system state (i.e., stress, pressure, temperature, and chemistry) with depth, and interpretation of material and system parameters relevant to numerical site simulation. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE

  9. Could Crop Roughness Impact the Wind Resource at Agriculturally Productive Wind Farm Sites?

    NASA Astrophysics Data System (ADS)

    Vanderwende, B. J.; Lundquist, J. K.

    2014-12-01

    The high concentration of both large-scale agriculture and wind power production in the United States Midwest region raises new questions concerning the interaction of the two activities. For instance, it is known from internal boundary layer theory that changes in the roughness of the land-surface resulting from crop choices could modify the momentum field aloft. Upward propagation of such an effect might impact the properties of the winds encountered by modern turbines, which typically span a layer from about 40 to 120 meters above the surface. As direct observation of such interaction would require impractical interference in the planting schedules of farmers, we use numerical modeling to quantify the magnitude of crop-roughness effects. To simulate a collocated farm and turbine array, we use version 3.4.1 of the Weather Research and Forecasting model (WRF). The hypothetical farm is inserted near the real location of the 2013 Crop Wind Energy Experiment (CWEX). Reanalyses provide representative initial and boundary conditions. A month-long period spanning August 2013 is used to evaluate the differences in flows above corn (maize) and soybean crops at the mature, reproductive stage. Simulations are performed comparing the flow above each surface regime, both in the absence and presence of a wind farm, which consists of a parameterized 11x11 array of 1.8 MW Vestas V90 turbines. Appreciable differences in rotor-layer wind speeds emerge. The use of soybeans results in an increase in wind speeds and a corresponding reduction in rotor-layer shear when compared to corn. Despite the turbulent nature of flow within a wind farm, high stability reduces the impact of crop roughness on the flow aloft, particularly in the upper portion of the rotor disk. We use these results to estimate the economic impact of crop selection on wind power producers.

  10. A modeling study on mitigation of N2O emissions and NO3 leaching at different agricultural sites across Europe using LandscapeDNDC.

    PubMed

    Molina-Herrera, Saúl; Haas, Edwin; Klatt, Steffen; Kraus, David; Augustin, Jürgen; Magliulo, Vincenzo; Tallec, Tiphaine; Ceschia, Eric; Ammann, Christof; Loubet, Benjamin; Skiba, Ute; Jones, Stephanie; Brümmer, Christian; Butterbach-Bahl, Klaus; Kiese, Ralf

    2016-05-15

    The identification of site-specific agricultural management practices in order to maximize yield while minimizing environmental nitrogen losses remains in the center of environmental pollution research. Here, we used the biogeochemical model LandscapeDNDC to explore different agricultural practices with regard to their potential to reduce soil N2O emissions and NO3 leaching while maintaining yields. In a first step, the model was tested against observations of N2O emissions, NO3 leaching, soil micrometeorology as well as crop growth for eight European cropland and grassland sites. Across sites, LandscapeDNDC predicts very well mean N2O emissions (r(2)=0.99) and simulates the magnitude and general temporal dynamics of soil inorganic nitrogen pools. For the assessment of site-specific mitigation potentials of environmental nitrogen losses a Monte Carlo optimization technique considering different agricultural management options (i.e., timing of planting, harvest and fertilization, amount of applied fertilizer as well as residue management) was used. The identified optimized field management practices reduce N2O emissions and NO3 leaching from croplands on average by 21% and 31%, respectively. Likewise, average reductions of 55% for N2O emissions and 16% for NO3 leaching are estimated for grasslands. For mitigating environmental loss - while maintaining yield levels - it was most important to reduce fertilizer application rates by in average 10%. Our analyses indicate that yield scaled N2O emissions and NO3 leaching indicate possible improvements of nitrogen use efficiencies in European farming systems. Moreover, the applied optimization approach can be used also in a prognostic way to predict optimal timings and fertilization options (rates and splitting) upon accurate weather forecasts combined with the knowledge of modeled soil nutrient availability and plant nitrogen demand. PMID:26909705

  11. Validation of SMAP Radar Vegetation Data Cubes from Agricultural Field Measurements

    NASA Astrophysics Data System (ADS)

    Tsang, L.; Xu, X.; Liao, T.; Kim, S.; Njoku, E. G.

    2012-12-01

    The NASA Soil Moisture Active/Passive (SMAP) Mission will be launched in October 2014. The objective of the SMAP mission is to provide global measurements of soil moisture and its freeze/thaw state. These measurements will be used to enhance understanding of processes that link the water, energy and carbon cycles, and to extend the capabilities of weather and climate prediction models. In the active algorithm, the retrieval is performed based on the backscattering data cube, which are characterized by two surface parameters, which are soil moisture and soil surface rms height, and one vegetation parameter, the vegetation water content. We have developed a physical-based forward scattering model to generate the data cube for agricultural fields. To represent the agricultural crops, we include a layer of cylinders and disks on top of the rough surface. The scattering cross section of the vegetation layer and its interaction with the underground soil surface were calculated by the distorted Born approximation, which give explicitly three scattering mechanisms. A) The direct volume scattering B) The double bounce effect as, and C) The double bouncing effects. The direct volume scattering is calculated by using the Body of Revolution code. The double bounce effects, exhibited by the interaction of rough surface with the vegetation layer is considered by modifying the rough surface reflectivity using the coherent wave as computed by Numerical solution of Maxwell equations of 3 Dimensional simulations (NMM3D) of bare soil scattering. The rough surface scattering of the soil was calculated by NMM3D. We have compared the physical scattering models with field measurements. In the field campaign, the measurements were made on soil moisture, rough surface rms heights and vegetation water content as well as geometric parameters of vegetation. The three main crops lands are grassland, cornfield and soybean fields. The corresponding data cubes are validated using SGP99, SMEX02

  12. Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California

    USGS Publications Warehouse

    Fujii, Roger; Deverel, S.J.; Hatfield, D.B.

    1988-01-01

    Soils from three agricultural fields in the Panoche Creek alluvial fan area in the western San Joaquin Valley, California, were analyzed for soluble, adsorbed, and total concentrations of selenium (Se) to assess the distribution and forms of Se in relation to the leaching of Se from soils. This assessment is needed to evaluate the importance of soil Se in affecting ground water concentrations. Soil samples were collected from three fields with drainage systems of different ages (6, 15, 1.5 yr) and different Se concentrations in drain water (58, 430, 3700 µg L−1, respectively). Concentrations of soluble Se and salinity were highest in soils from the field drained for 1.5 yr and lowest in the field drained for 6 yr. Of the total concentration of soil Se from all three fields, the proportion of adsorbed and soluble Se ranged from 1 to 11% and 2 > 0.68) in saturation extracts of soils sampled from below the water table. In contrast, most soluble salts and Se apparently have been leached from the unsaturated soils in the fields drained for 6 and 15 yr. For the leached soils, dissolution and precipitation of evaporite minerals containing Se may no longer control concentrations of soluble Se.

  13. Mapping the soil health of agricultural fields via soil electrical conductivity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Claypan soils in the central USA have experienced severe erosion as a result of tillage practices of the late 1800s and 1900s. Because of the site-specific nature of erosion processes within claypan fields, research is needed to achieve cost-effective sensing and mapping of soil and landscape proper...

  14. Temporal stability of estimated soil water flux patterns across agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When a field or a small watershed is repeatedly surveyed for soil water content, sites often can be spotted where soil is consistently wetter or consistently dryer than average across the study area. This phenomenon has been called time stability, temporal stability, temporal persistence, or rank st...

  15. Site Study Plan for Aesthetics, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-06-01

    The Aesthetic Site Study Plan describes a field program consisting of identification of the visually affected area; determination of scenic quality, visual sensitivity, and visual management classes of the site and vicinity; and analysis of the level of visual contrast that would be created by the project. Field ratings of scenic quality, visual sensitivity, and visual contrast will be supplemented by a public perception survey designed to incorporate the views of the public. This plan describes the need for the study, the study design, data management and use, schedule for proposed activities, and quality assurance program. This study will provide data needed to satisfy requirements contained in, or derived from, SRPO Requirement Document (SRP-RD). 35 refs., 6 figs., 2 tabs.

  16. Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California

    USGS Publications Warehouse

    Fujii, Roger; Deverel, S.J.; Hatfield, D.B.

    1987-01-01

    Soils from three agricultural fields in the western San Joaquin Valley were analyzed for soluble, adsorbed, and total concentrations of selenium (Se) to assess the distribution and forms of Se, and the relation of the distribution and forms of Se to the leaching of Se from soils. Soil samples were collected in three fields with drainage systems of different ages (6, 15, 1.5 yr) and different Se concentrations in drain water (58, 430, 3700 micrograms/L respectively). Preliminary methods to determine total Se and estimate adsorbed Se were developed. Of the three fields, concentrations of soluble Se and salinity were highest in soils from the field drained for 1.5 yr and lowest in the field drained for 6 yr. The field drained for 1.5 yr also had the highest concentration of total Se in soil; a median of 1.2 microgram/gm. Of the total concentration of Se in soil from all three fields, the proportion of adsorbed Se and soluble Se ranged from 1 to 11% and < 1 to 63%, respectively. Most of the variance in soluble Se is explained by salinity ( r sq > 0.68) in saturation extracts of soils sampled from below the water table, reflecting evaporative concentration of Se and salinity. In contrast, most soluble salts and Se apparently have been leached from the unsaturated soils in the fields drained for 6 and 15 yr; therefore, the correlation was lower between Se and salinity in saturation extracts of those soils (r sq < 0.33). Among soils from all three fields, the ratio of Se to salinity in saturation extracts increased with increasing salinity. (Author 's abstract)

  17. Plot and Catchment Scale Hydrological Impacts of Agricultural Field Boundary Features

    NASA Astrophysics Data System (ADS)

    Coates, Victoria; Pattison, Ian

    2015-04-01

    Natural flood management aims to reduce downstream flow levels by delaying the movement of water through a catchment and increasing the amount of soil infiltration. Field boundary features such as hedgerows and dry stone walls are common features in the rural landscape. It is hypothesised that there presence could reduce runoff connectivity and change the soil moisture levels by altering the soil structure and porosity. The use of larger agricultural machinery has resulted in the removal of field boundaries and the subsequent increase in field sizes over the 20th Century. This change in the rural landscape is likely to have changed the partitioning of rainfall into runoff and the hydrological pathways throughout the catchment. However, the link between field boundaries and catchment scale flood risk has not yet been proven. We aim to address this need for evidence to support natural flood management by focussing on these widespread features in the rural landscape. Firstly, we quantify the change in the density of field boundaries over the past 120 years for the Skell catchment, Northern England using historical OS maps. The analysis has shown that field size has approximately doubled in the Skell catchment since 1892, due to the removal of field boundaries. Secondly, we assess the effect of field boundaries on local soil characteristics and hydrological processes through plot scale continuous monitoring of the hydrological processes along a 20m transect through the linear boundary features. For the summer period results show that soil moisture levels are lower immediately next to the hedgerow compared to distances greater than 1m from the hedgerow. Finally, we use this data to parameterise and validate a catchment scale hydrological model. The model is then applied to test the impact of a network of field boundaries on river flow extremes at the catchment scale.

  18. Trichoderma Biodiversity of Agricultural Fields in East China Reveals a Gradient Distribution of Species

    PubMed Central

    Chen, Jing; Mao, Li-Juan; Feng, Xiao-Xiao; Zhang, Chu-Long; Lin, Fu-Cheng

    2016-01-01

    We surveyed the Trichoderma (Hypocreales, Ascomycota) biodiversity in agricultural fields in four major agricultural provinces of East China. Trichoderma strains were identified based on molecular approaches and morphological characteristics. In three sampled seasons (spring, summer and autumn), 2078 strains were isolated and identified to 17 known species: T. harzianum (429 isolates), T. asperellum (425), T. hamatum (397), T. virens (340), T. koningiopsis (248), T. brevicompactum (73), T. atroviride (73), T. fertile (26), T. longibrachiatum (22), T. pleuroticola (16), T. erinaceum (16), T. oblongisporum (2), T. polysporum (2), T. spirale (2), T. capillare (2), T. velutinum (2), and T. saturnisporum (1). T. harzianum, T. asperellum, T. hamatum, and T. virens were identified as the dominant species with dominance (Y) values of 0.057, 0.052, 0.048, and 0.039, respectively. The species amount, isolate numbers and the dominant species of Trichoderma varied between provinces. Zhejiang Province has shown the highest diversity, which was reflected in the highest species amount (14) and the highest Shannon–Wiener diversity index of Trichoderma haplotypes (1.46). We observed that relative frequencies of T. hamatum and T. koningiopsis under rice soil were higher than those under wheat and maize soil, indicating the preference of Trichoderma to different crops. Remarkable seasonal variation was shown, with summer exhibiting the highest biodiversity of the studied seasons. These results show that Trichoderma biodiversity in agricultural fields varies by region, crop, and season. Zhejiang Province (the southernmost province in the investigated area) had more T. hamatum than Shandong Province (the northernmost province), not only in isolate amounts but also in haplotype amounts. Furthermore, at haplotype level, only T. hamatum showed a gradient distribution from south to north in correspondence analysis among the four dominant species. The above results would contribute to the

  19. Earthworm tolerance to residual agricultural pesticide contamination: field and experimental assessment of detoxification capabilities.

    PubMed

    Givaudan, Nicolas; Binet, Françoise; Le Bot, Barbara; Wiegand, Claudia

    2014-09-01

    This study investigates if acclimatization to residual pesticide contamination in agricultural soils is reflected in detoxification, antioxidant enzyme activities and energy budget of earthworms. Five fields within a joint agricultural area exhibited different chemical and farming histories from conventional cultivation to organic pasture. Soil multiresidual pesticide analysis revealed up to 9 molecules including atrazine up to 2.4 ng g(-1) dry soil. Exposure history of endogeic Aporrectodea caliginosa and Allolobophora chlorotica modified their responses to pesticides. In the field, activities of soluble glutathione-S-transferases (sGST) and catalase increased with soil pesticide contamination in A. caliginosa. Pesticide stress was reflected in depletion of energy reserves in A. chlorotica. Acute exposure of pre-adapted and naïve A. caliginosa to pesticides (fungicide Opus(®), 0.1 μg active ingredient epoxiconazole g(-1) dry soil, RoundUp Flash(®), 2.5 μg active ingredient glyphosate g(-1) dry soil, and their mixture), revealed that environmental pre-exposure accelerated activation of the detoxification enzyme sGST towards epoxiconazole. PMID:24874794

  20. Gully evolution in field crops on vertic soils under conventional agriculture

    NASA Astrophysics Data System (ADS)

    Castillo, Carlos; Pérez, Rafael; Mora, Jose; Gómez, Jose A.

    2015-04-01

    Gully erosion is a major process contributing to soil degradation on cultivated areas. Its effects are especially intense in farms under conventional agriculture characterised by the use of heavy machinery for land levelling and herbicides leading to the depletion of natural vegetation in valley locations. When the soil (e.g. vertic soils) and parent material conditions (e.g. soft erodible marls) are favourable to incision, gully features may present large dimensions, producing the loss of significant proportions of productive land. This study evaluates the evolution of several gully networks located in Córdoba (Spain) within the Campiña area (a rolling landscape on Miocene marls) with conventional agriculture and gully filling operations as the predominant farm practices. The area of the catchments ranged from 10 to 100 ha, they were covered by field crops (mostly bean, sunflower and wheat) on vertic soils. Firstly, we carried out a historical analysis of the gully development during the last six decades by aerial image interpretation. Secondly, a number of field surveys were conducted to characterise the evolution of the gully morphology in a period of five years (2010-2014). For this purpose, a range of measurement techniques were used: pole and tape, differential GPS and 3D photo-reconstruction. Finally, the influence of topography (slope and drainage area) on gully dimensions along the longitudinal profile was assessed.

  1. Vegetation water content mapping in a diverse agricultural landscape: National Airborne Field Experiment 2006

    NASA Astrophysics Data System (ADS)

    Cosh, Michael H.; Tao, Jing; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2010-05-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE'06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE'06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/m2. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy.

  2. Meteorological and associated data collected over agricultural fields in Pinal County, Arizona, 1989 and 1990

    USGS Publications Warehouse

    Owen-Joyce, Sandra J.; Brown, Paul W.

    1995-01-01

    Data were collected at temporary meteorological stations installed in agricultural fields in Pinal County, Arizona, to evaluate the spatial and temporal variability of point data and to examine how station location affects ground-based meteorological data and the resulting values of evapotranspiration calculated using remotely sensed multispectral data from satellites. Time-specific data were collected to correspond with satellite overpasses from April to October 1989, and June 27-28, 1990. Meteorological data consisting of air temperature, relative humidity, wind speed, solar radiation, and net radiation were collected at each station during all periods of the project. Supplementary measurements of soil temperature, soil heat flux density, and surface or canopy temperature were obtained at some locations during certain periods of the project. Additional data include information on data-collection periods, station positions, instrumentation, sensor heights, and field dimensions. Other data, which correspond to the extensive field measurements made in con- junction with satellite overpasses in 1989 and 1990, include crop type, canopy cover, canopy height, irrigation, cultivation, and orientation of rows. Field boundaries and crop types were mapped in a 2- to 3-square-kilometer area surrounding each meteorological station. Field data are presented in tabular and graphic form. Meteorological and supplementary data are available, upon request, in digital form.

  3. Scaling preferential flow processes in agricultural soils affected by tillage and trafficking at the field scale

    NASA Astrophysics Data System (ADS)

    Filipović, Vilim; Coquet, Yves

    2016-04-01

    There is an accumulation of experimental evidences that agricultural soils, at least the top horizons affected by tillage practices, are not homogeneous and present a structure that is strongly dependent on farming practices like tillage and trafficking. Soil tillage and trafficking can create compacted zones in the soil with hydraulic properties and porosity which are different from those of the non-compacted zones. This spatial variability can strongly influence transport processes and initiate preferential flow. Two or three dimensional models can be used to account for spatial variability created by agricultural practices, but such models need a detailed assessment of spatial heterogeneity which can be rather impractical to provide. This logically raises the question whether and how one dimensional model may be designed and used to account for the within-field spatial variability in soil structure created by agricultural practices. Preferential flow (dual-permeability) modelling performed with HYDRUS-1D will be confronted to classical modelling based on the Richards and convection-dispersion equations using HYDRUS-2D taking into account the various soil heterogeneities created by agricultural practices. Our goal is to derive one set of equivalent 1D soil hydraulic parameters from 2D simulations which accounts for soil heterogeneities created by agricultural operations. A field experiment was carried out in two phases: infiltration and redistribution on a plot by uniform sprinkle irrigation with water or bromide solution. Prior to the field experiment the soil structure of the tilled layer was determined along the face of a large trench perpendicular to the tillage direction (0.7 m depth and 3.1 m wide). Thirty TDR probes and tensiometers were installed in different soil structural zones (Δ compacted soil and Γ macroporous soil) which ensured soil water monitoring throughout the experiment. A map of bromide was constructed from small core samples (4 cm diam

  4. Field and laboratory tests for assessing the feasibility on the use of municipal treated wastewater for agricultural irrigation

    NASA Astrophysics Data System (ADS)

    Gallardo, Helena; Lovera, Raúl; Himi, Mahjoub; Sendrós, Alexandre; Marguí, Eva; Tapias, Josefina C.; Queralt, Ignasi; Casas, Albert

    2014-05-01

    he scarcity of water resources in many regions of the planet in the XXIst century is a challenge which concerns the current societies. Water use has been growing during the last decades. Therefore, different strategies of water management in many water-deficient regions are being carried out, especially in densely populated areas, in coastal zones or in regions under arid or semi-arid climate. During the last years, there has been a growing interest in the use of the subsurface for water storage though shallow percolating ponds. Moreover, on a best-practices basis, the use of reclaimed wastewater for different purposes is becoming more usual. The irrigation with municipal treated wastewater (MTWW) is an interesting strategy especially in the agricultural sector, which represents the main water user in contrast with other socioeconomic activities. The study area is located near Castellbisbal, on the lower stretches of the Llobregat River close to the Metropolitan area of Barcelona (Catalonia, Spain). The site consists on a percolating pond and agricultural fields around. In order to assess the feasibility of using reclaimed wastewater for different uses in this site, several experiments both on field and at the laboratory were carried out. First of all, a detailed non-destructive geophysical survey was conducted using electrical resistivity tomography (ERT) technique. Geophysical data were constrained by geological and hydrogeological properties from boreholes and water wells. On the other hand, laboratory experiments were carried out through batch and column assays, focused on the detailed water-mineral particles interrelationships that can occur at the vadose zone. Soil samples from the crop fields around and water samples from the nearest well, as from the municipal wastewater treatment plant were used. Chemical and mineralogical composition of the soils were determined by using non-destructive spectroscopic techniques as x-ray fluorescence (XRF) and x-ray powder

  5. SITE IVESTIGATIONS (SI) AND FIELD INVESTIGATIONS (FI) OF REGION 4 SUPERFUND HAZARDOUS WASTE SITES: OCTOBER 2005 – SEPTEMBER 2006

    EPA Science Inventory

    Site Investigations (SIs) and expanded Field Investigations (FIs) conducted by the Region 4 Science and Ecosystem Support Division (SESD) require developing and implementing work plans which include a Project Operations Plan, Field Sampling and Analysis Plan, Quality Assurance Pl...

  6. SITE IVESTIGATIONS (SI) AND FIELD INVESTIGATIONS (FI) OF REGION 4 SUPERFUND HAZARDOUS WASTE SITES: AUGUST 2007 – SEPTEMBER 2008

    EPA Science Inventory

    Site Investigations (SIs) and Field Investigations (FIs) conducted by the Region 4 Science and Ecosystem Support Division (SESD) require developing and implementing work plans which include a Project Operations Plan, Field Sampling and Analysis Plan, Quality Assurance Project Pla...

  7. SITE INVESTIGATIONS (SI) AND FIELD INVESTIGATIONS (FI) OF REGION 4 SUPERFUND HAZARDOUS WASTE SITES: OCTOBER 2006 – JULY 2007

    EPA Science Inventory

    Site Investigations (SIs) and Field Investigations (FIs) conducted by the Region 4 Science and Ecosystem Support Division (SESD) require developing and implementing work plans which include a Project Operations Plan, Field Sampling and Analysis Plan, Quality Assurance Project Pla...

  8. Evaluation of agricultural best-management practices in the Conestoga River headwaters, Pennsylvania; hydrology of a small carbonate site near Ephrata, Pennsylvania, prior to implementation of nutrient management

    USGS Publications Warehouse

    Koerkle, E.H.; Hall, D.W.; Risser, D.W.; Lietman, P.L.; Chichester, D.C.

    1997-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture and Pennsylvania Department of Environmental Protection, investigated the effects of agricultural best-management practices on water quality in the Conestoga River headwaters watershed. This report describes environmental factors and the surface-water and ground-water quality of one 47.5-acre field site, Field-Site 2, from October 1984 through September 1986, prior to implementation of nutrient management. The site is partially terraced agricultural cropland underlain by carbonate rock. Twenty-seven acres are terraced, pipe-drained, and are under no-till cultivation. The remaining acreage is under minimum-till cultivation. Corn is the primary crop. The average annual rate of fertilization at the site was 480 pounds per acre of nitrogen and 110 pounds per acre of phosphorus. An unconfined limestone and dolomitic aquifer underlies the site, Depth to bedrock ranges from 5 to 30 feet below land surface. Estimated specific yields range from 0.05 to 0.10, specific capacities of wells range from less than 1 to about 20 gallons per minute per foot of drawdown, and estimates of transmissivities range from 10 to 10,000 square feet per day. Average ground-water recharge was estimated to be about 23 inches per year. The specific capacity and transmissivity data indicate that two aquifer regimes are present at the site. Wells drilled into dolomites in the eastern part of the site have larger specific capacities (averaging 20 gallons per minute per foot of drawdown) relative to specific capacities (averaging less than 1 gallon per minute per foot of drawdown) of wells drilled into limestones in the western part of the site. Median concentrations of soil-soluble nitrate and soluble phosphorus in the top 4 feet of silt- or silty-clay-loam soil ranged from 177 to 329 and 8.5 to 35 pounds per acre, respectively. Measured runoff from the pipe-drained terraces ranged from 10 to 48,000 cubic feet and was

  9. Monitoring soil moisture dynamics via ground-penetrating radar survey of agriculture fields after irrigation

    NASA Astrophysics Data System (ADS)

    Muro, G.

    2015-12-01

    It is possible to examine the quality of ground-penetrating radar (GPR) as a measure of soil moisture content in the shallow vadose zone, where roots are most abundant and water conservation best management practices are critical in active agricultural fields. By analyzing temporal samplings of 100 Mhz reflection profiles and common-midpoint (CMP) soundings over a full growing season, the variability of vertical soil moisture distribution directly after irrigation events are characterized throughout the lifecycle of a production crop. Reflection profiles produce high-resolution travel time data and summed results of CMP sounding data provide sampling depth estimates for the weak, but coherent reflections amid strong point scatterers. The high ratio of clay in the soil limits the resolution of downward propagation of infiltrating moisture after irrigation; synthetic data analysis compared against soil moisture lysimeter logs throughout the profile allow identification of the discrete soil moisture content variation in the measured GPR data. The nature of short duration irrigation events, evapotranspiration, and drainage behavior in relation to root depths observed in the GPR temporal data allow further examination and comparison with the variable saturation model HYDRUS-1D. After retrieving soil hydraulic properties derived from laboratory measured soil samples and simplified assumptions about boundary conditions, the project aims to achieve good agreement between simulated and measured soil moisture profiles without the need for excessive model calibration for GPR-derived soil moisture estimates in an agricultural setting.

  10. Mycotoxins in the environment: I. Production and emission from an agricultural test field.

    PubMed

    Schenzel, Judith; Forrer, Hans-Rudolf; Vogelgsang, Susanne; Hungerbühler, Konrad; Bucheli, Thomas D

    2012-12-18

    Mycotoxins are secondary metabolites that are naturally produced by fungi which infest and contaminate agricultural crops and commodities (e.g., small grain cereals, fruits, vegetables, and organic soil material). Although these compounds have extensively been studied in food and feed, only little is known about their environmental fate. Therefore, we investigated over nearly two years the occurrence of various mycotoxins in a field cropped with winter wheat of the variety Levis, which was artificially inoculated with Fusarium spp., as well as their emission via drainage water. Mycotoxins were regularly quantified in whole wheat plants (0.1-133 mg/kg(dry weight), for deoxynivalenol), and drainage water samples (0.8 ng/L to 1.14 μg/L, for deoxynivalenol). From the mycotoxins quantified in wheat (3-acetyl-deoxynivalenol, deoxynivalenol, fusarenone-X, nivalenol, HT-2 toxin, T-2 toxin, beauvericin, and zearalenone), only the more hydrophilic ones or those prevailing at high concentrations were detected in drainage water. Of the total amounts produced in wheat plants (min: 2.3; max: 292 g/ha/y), 0.5-354 mg/ha/y, i.e. 0.002-0.12%, were emitted via drainage water. Hence, these compounds add to the complex mixture of natural and anthropogenic micropollutants particularly in small rural water bodies, receiving mainly runoff from agricultural areas. PMID:23145781

  11. Long-term comparison of energy flux calculation methods over an agricultural field

    NASA Astrophysics Data System (ADS)

    Kolle, O.

    1996-05-01

    Since March 1990 micrometeorological measurements were carried out over an agricultural field with varying land use (wheat, barley, sunflowers, mustard) using a profile mast and an energy balance mast with an eddy correlation system for the sensible heat flux. Soil temperature, soil heat flux, soil moisture and precipitation were measured as well. Long-term measurements allow statistical analysis of the energy fluxes and comparisons of different methods for their calculation (eddy correlation, flux profile, Bowen ratio and the residual method). For the sensible heat flux a good agreement was found using these different methods after applying all necessary corrections. The latent heat flux shows greater deviations in the daily cycle between the flux profile method and the residual method due to the shape of the humidity profiles which often and especially at night show a maximum at heights between 1 m and 4 m, even if the soil is free of vegetation. This could be a consequence of the patchiness of the agricultural area, the position of the station on top of a hillock or high water absorption of the soil, respectively. The residual method seems to give more reliable results for the actual evapotranspiration than the flux profile method or the Bowen ratio method if an eddy correlation system is used to determine the sensible heat flux. Differences in the soil heat flux measured with heat flux plates and determined using the profiles of soil temperature and soil moisture can be explained by the heat flux plates being a disturbance to the soil matrix.

  12. Site study plan for ecology, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary Draft

    SciTech Connect

    Not Available

    1987-06-01

    The Ecology Site Study Plan describes a field program consisting of studies which include surveys for endangered, threatened, and candidate species; vegetation characterization, including mapping and cover typing, plant succession, wetlands description, and preexisting stresses; and wildlife community characterization, including availability and quality of habitats and descriptions of mammal, bird, reptile, amphibian, and invertebrate populations. The plan for each study describes the need for the study, study design, data management and use, schedule and personnel requirements, and quality assurance. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Project Requirements Document (SRP-RD). 83 refs., 3 tabs.

  13. On dealing with the pollution costs in agriculture: A case study of paddy fields.

    PubMed

    Yaqubi, Morteza; Shahraki, Javad; Sabouhi Sabouni, Mahmood

    2016-06-15

    The main purpose of this study is to evaluate marginal abatement cost of the main agricultural pollutants. In this sense, we construct three indices including Net Global Warming Potential (NGWP) and Nitrogen Surplus (NS), simulated by a biogeochemistry model, and also an Environmental Impact Quotient (EQI) for paddy fields. Then, using a Data Envelopment Analysis (DEA) model, we evaluate environmental inefficiencies and shadow values of these indices. The results show that there is still room for improvement at no extra cost just through a better input management. Besides, enormous potential for pollution reduction in the region is feasible. Moreover, in paddy cultivation, marginal abatement cost of pesticides and herbicides are much bigger than nitrogen surplus and greenhouse gasses. In addition, in the status quo, the mitigation costs are irrelevant to production decisions. Finally, to deal with the private pollution costs, market-based instruments are proved to be better than command-and-control regulation. PMID:26998602

  14. Reactive transport studies at the Raymond Field Site

    SciTech Connect

    Freifeld, B.; Karasaki, K.; Solbau, R.; Cohen, A.

    1995-12-01

    To ensure the safety of a nuclear waste repository, an understanding of the transport of radionuclides from the repository nearfield to the biosphere is necessary. At the Raymond Field Site, in Raymond, California, tracer tests are being conducted to test characterization methods for fractured media and to evaluate the equipment and tracers that will be used for Yucca Mountain`s fracture characterization. Recent tracer tests at Raymond have used reactive cations to demonstrate transport with sorption. A convective-dispersive model was used to simulate a two-well recirculating test with reasonable results. However, when the same model was used to simulate a radially convergent tracer test, the model poorly predicted the actual test data.

  15. Evaluation of Three Models for Simulating Pesticide Runoff from Irrigated Agricultural Fields.

    PubMed

    Zhang, Xuyang; Goh, Kean S

    2015-11-01

    Three models were evaluated for their accuracy in simulating pesticide runoff at the edge of agricultural fields: Pesticide Root Zone Model (PRZM), Root Zone Water Quality Model (RZWQM), and OpusCZ. Modeling results on runoff volume, sediment erosion, and pesticide loss were compared with measurements taken from field studies. Models were also compared on their theoretical foundations and ease of use. For runoff events generated by sprinkler irrigation and rainfall, all models performed equally well with small errors in simulating water, sediment, and pesticide runoff. The mean absolute percentage errors (MAPEs) were between 3 and 161%. For flood irrigation, OpusCZ simulated runoff and pesticide mass with the highest accuracy, followed by RZWQM and PRZM, likely owning to its unique hydrological algorithm for runoff simulations during flood irrigation. Simulation results from cold model runs by OpusCZ and RZWQM using measured values for model inputs matched closely to the observed values. The MAPE ranged from 28 to 384 and 42 to 168% for OpusCZ and RZWQM, respectively. These satisfactory model outputs showed the models' abilities in mimicking reality. Theoretical evaluations indicated that OpusCZ and RZWQM use mechanistic approaches for hydrology simulation, output data on a subdaily time-step, and were able to simulate management practices and subsurface flow via tile drainage. In contrast, PRZM operates at daily time-step and simulates surface runoff using the USDA Soil Conservation Service's curve number method. Among the three models, OpusCZ and RZWQM were suitable for simulating pesticide runoff in semiarid areas where agriculture is heavily dependent on irrigation. PMID:26641333

  16. Green house gas emissions from open field burning of agricultural residues in India.

    PubMed

    Murali, S; Shrivastava, Rajnish; Saxena, Mohini

    2010-10-01

    In India, about 435.98 MMT of agro-residues are produced every year, out of which 313.62 MMT are surplus. These residues are either partially utilized or un-utilised due to various constraints. To pave the way for subsequent season for agriculture activity, the excess crop residues are burnt openly in the fields, unmindful of their ill effects on the environment. The present study has been undertaken to evaluate the severity of air pollution through emission of green house gases (GHGs) due to open field burning of agro-residues in India. Open field burning of surplus agro-residues in India results in the emission of GHG. Emissions of CH4 and N2O in 1997-98 and 2006-07 have been 3.73 and 4.06 MMT CO2 equivalent, which is an increase of 8.88% over a decade. About three-fourths of GHG emissions from agro-residues burning were CH4 and the remaining one-fourth were N2O. Burning of wheat and paddy straws alone contributes to about 42% of GHGs. These GHG emissions can be avoided once the agro-residues are employed for sustainable, cost-effective and environment- friendly options like power generation. PMID:22312795

  17. Agricultural and Management Practices and Bacterial Contamination in Greenhouse versus Open Field Lettuce Production

    PubMed Central

    Holvoet, Kevin; Sampers, Imca; Seynnaeve, Marleen; Jacxsens, Liesbeth; Uyttendaele, Mieke

    2014-01-01

    The aim of this study was to gain insight into potential differences in risk factors for microbial contamination in greenhouse versus open field lettuce production. Information was collected on sources, testing, and monitoring and if applicable, treatment of irrigation and harvest rinsing water. These data were combined with results of analysis on the levels of Escherichia coli as a fecal indicator organism and the presence of enteric bacterial pathogens on both lettuce crops and environmental samples. Enterohemorragic Escherichia coli (EHEC) PCR signals (vt1 or vt2 positive and eae positive), Campylobacter spp., and Salmonella spp. isolates were more often obtained from irrigation water sampled from open field farms (21/45, 46.7%) versus from greenhouse production (9/75, 12.0%). The open field production was shown to be more prone to fecal contamination as the number of lettuce samples and irrigation water with elevated E. coli was significantly higher. Farmers comply with generic guidelines on good agricultural practices available at the national level, but monitoring of microbial quality, and if applicable appropriateness of water treatment, or water used for irrigation or at harvest is restricted. These results indicate the need for further elaboration of specific guidelines and control measures for leafy greens with regard to microbial hazards. PMID:25546272

  18. Export of radioactive cesium from agricultural fields under simulated rainfall in Fukushima.

    PubMed

    Thai, Phong K; Suka, Yuma; Sakai, Masaru; Nanko, Kazuki; Yen, Jui-Hung; Watanabe, Hirozumi

    2015-06-01

    In this study, we investigated the impact of rainfall on runoff, soil erosion and consequently on the discharge of radioactive cesium in agricultural fields in Fukushima prefecture using a rainfall simulator. Simulated heavy rainfalls (50 mm h(-1)) generated significant runoff and soil erosion. The average concentration of radioactive cesium (the sum of (134)Cs and (137)Cs) in the runoff sediments was ∼3500 Bq kg(-1) dry soil, more than double the concentrations measured in the field soils which should be considered in studies using the (137)Cs loss to estimate long-term soil erosion. However, the estimated mass of cesium discharged through one runoff event was less than 2% of the cesium inventory in the field. This suggested that cesium discharge via soil erosion is not a significant factor in reducing the radioactivity of contaminated soils in Fukushima prefecture. However, the eroded sediment carrying radioactive cesium will deposit into the river systems and potentially pose a radioactivity risk for aquatic living organisms. PMID:25976360

  19. Use of airborne hyperspectral imagery to map soil parameters in tilled agricultural fields

    USGS Publications Warehouse

    Hively, W. Dean; McCarty, Gregory W.; Reeves, James B., III; Lang, Megan W.; Oesterling, Robert A.; Delwiche, Stephen R.

    2011-01-01

    Soil hyperspectral reflectance imagery was obtained for six tilled (soil) agricultural fields using an airborne imaging spectrometer (400–2450 nm, ~10 nm resolution, 2.5 m spatial resolution). Surface soil samples (n = 315) were analyzed for carbon content, particle size distribution, and 15 agronomically important elements (Mehlich-III extraction). When partial least squares (PLS) regression of imagery-derived reflectance spectra was used to predict analyte concentrations, 13 of the 19 analytes were predicted with R2 > 0.50, including carbon (0.65), aluminum (0.76), iron (0.75), and silt content (0.79). Comparison of 15 spectral math preprocessing treatments showed that a simple first derivative worked well for nearly all analytes. The resulting PLS factors were exported as a vector of coefficients and used to calculate predicted maps of soil properties for each field. Image smoothing with a 3 × 3 low-pass filter prior to spectral data extraction improved prediction accuracy. The resulting raster maps showed variation associated with topographic factors, indicating the effect of soil redistribution and moisture regime on in-field spatial variability. High-resolution maps of soil analyte concentrations can be used to improve precision environmental management of farmlands.

  20. Microbial respiration and kinetics of extracellular enzymes activities through rhizosphere and detritusphere at agricultural site

    NASA Astrophysics Data System (ADS)

    Löppmann, Sebastian; Blagodatskaya, Evgenia; Kuzyakov, Yakov

    2014-05-01

    Rhizosphere and detritusphere are soil microsites with very high resource availability for microorganisms affecting their biomass, composition and functions. In the rhizosphere low molecular compounds occur with root exudates and low available polymeric compounds, as belowground plant senescence. In detritusphere the substrate for decomposition is mainly a polymeric material of low availability. We hypothesized that microorganisms adapted to contrasting quality and availability of substrates in the rhizosphere and detritusphere are strongly different in affinity of hydrolytic enzymes responsible for decomposition of organic compounds. According to common ecological principles easily available substrates are quickly consumed by microorganisms with enzymes of low substrate affinity (i.e. r-strategists). The slow-growing K-strategists with enzymes of high substrate affinity are better adapted for growth on substrates of low availability. Estimation of affinity of enzyme systems to the substrate is based on Michaelis-Menten kinetics, reflecting the dependency of decomposition rates on substrate amount. As enzymes-mediated reactions are substrate-dependent, we further hypothesized that the largest differences in hydrolytic activity between the rhizosphere and detritusphere occur at substrate saturation and that these differences are smoothed with increasing limitation of substrate. Affected by substrate limitation, microbial species follow a certain adaptation strategy. To achieve different depth gradients of substrate availability 12 plots on an agricultural field were established in the north-west of Göttingen, Germany: 1) 4 plots planted with maize, reflecting lower substrate availability with depth; 2) 4 unplanted plots with maize litter input (0.8 kg m-2 dry maize residues), corresponding to detritusphere; 3) 4 bare fallow plots as control. Maize litter was grubbed homogenously into the soil at the first 5 cm to ensure comparable conditions for the herbivore and

  1. Source apportionment of groundwater pollutants in Apulian agricultural sites using multivariate statistical analyses: case study of Foggia province

    PubMed Central

    2012-01-01

    Background Ground waters are an important resource of water supply for human health and activities. Groundwater uses and applications are often related to its composition, which is increasingly influenced by human activities. In fact the water quality of groundwater is affected by many factors including precipitation, surface runoff, groundwater flow, and the characteristics of the catchment area. During the years 2004-2007 the Agricultural and Food Authority of Apulia Region has implemented the project “Expansion of regional agro-meteorological network” in order to assess, monitor and manage of regional groundwater quality. The total wells monitored during this activity amounted to 473, and the water samples analyzed were 1021. This resulted in a huge and complex data matrix comprised of a large number of physical-chemical parameters, which are often difficult to interpret and draw meaningful conclusions. The application of different multivariate statistical techniques such as Cluster Analysis (CA), Principal Component Analysis (PCA), Absolute Principal Component Scores (APCS) for interpretation of the complex databases offers a better understanding of water quality in the study region. Results Form results obtained by Principal Component and Cluster Analysis applied to data set of Foggia province it’s evident that some sampling sites investigated show dissimilarities, mostly due to the location of the site, the land use and management techniques and groundwater overuse. By APCS method it’s been possible to identify three pollutant sources: Agricultural pollution 1 due to fertilizer applications, Agricultural pollution 2 due to microelements for agriculture and groundwater overuse and a third source that can be identified as soil run off and rock tracer mining. Conclusions Multivariate statistical methods represent a valid tool to understand complex nature of groundwater quality issues, determine priorities in the use of ground waters as irrigation water

  2. 300 Area Integrated Field-Scale Subsurface Research Challenge (IFRC) Field Site Management Plan

    SciTech Connect

    Freshley, Mark D.

    2008-12-31

    Pacific Northwest National Laboratory (PNNL) has established the 300 Area Integrated Field-Scale Subsurface Research Challenge (300 Area IFRC) on the Hanford Site in southeastern Washington State for the U.S. Department of Energy’s (DOE) Office of Biological and Environmental Research (BER) within the Office of Science. The project is funded by the Environmental Remediation Sciences Division (ERSD). The purpose of the project is to conduct research at the 300 IFRC to investigate multi-scale mass transfer processes associated with a subsurface uranium plume impacting both the vadose zone and groundwater. The management approach for the 300 Area IFRC requires that a Field Site Management Plan be developed. This is an update of the plan to reflect the installation of the well network and other changes.

  3. Increased spring flooding of agricultural fields will exhibit altered production of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Paul, R. F.; Smith, C. M.; Smyth, E. M.; Kantola, I. B.; DeLucia, E. H.

    2013-12-01

    The U.S. Corn Belt currently is a net source of carbon dioxide and nitrous oxide to the atmosphere, but is also a sink of methane. Among the proposed effects of climate change in the North American Midwest region is an increase in the frequency and duration of spring flooding events. This would cause ponding in fields which may change the greenhouse gas balance of the region, especially by providing a suitable anoxic environment for the proliferation of methanogens, increasing methane emissions. To determine whether methanogenesis occurs in flooded agricultural soils of the Midwest and how other gas fluxes are affected, we installed collars into the ground of a research field located in central Illinois. The control group was maintained at the same conditions as the surrounding field. Two groups of collars were sustained with water flooding the headspaces via a drip irrigation system; one treatment was analyzed for gas fluxes of CH4, N2O, and CO2 evolving from the collars, and a separate treatment of flooded collars was used for soil sampling. Comparing flooded soils versus control we measured reduced N2O fluxes (-3.12 x 10-6 × 6.8 x 10-7 g N m-2 min-1), reduced CO2 fluxes (-6.13 x 10-3 × 9.3 x 10-4 g CO2 m-2 min-1), and increased methane fluxes (+2.72 x 10-6 × 5.8 x 10-7 g CH4 m-2 min-1). After only one week of treatment the flooded soils switched from being sinks to sources of methane, which continued across the duration of the experiment. These preliminary results indicate that methanogenesis occurs in flooded agricultural fields, and suggest including regional modeling into further study. Although the global warming potential of methane is 25 times greater than CO2, our measured rates of methane production were compensated by reductions in nitrous oxide and CO2 fluxes, reducing the total 100-year horizon global warming potential of the flooded soils we studied by 64.8%. This indicates that accounting for more frequent seasonal ponding would significantly

  4. A Site-sPecific Agricultural water Requirement and footprint Estimator (SPARE:WATER 1.0)

    NASA Astrophysics Data System (ADS)

    Multsch, S.; Al-Rumaikhani, Y. A.; Frede, H.-G.; Breuer, L.

    2013-07-01

    The agricultural water footprint addresses the quantification of water consumption in agriculture, whereby three types of water to grow crops are considered, namely green water (consumed rainfall), blue water (irrigation from surface or groundwater) and grey water (water needed to dilute pollutants). By considering site-specific properties when calculating the crop water footprint, this methodology can be used to support decision making in the agricultural sector on local to regional scale. We therefore developed the spatial decision support system SPARE:WATER that allows us to quantify green, blue and grey water footprints on regional scale. SPARE:WATER is programmed in VB.NET, with geographic information system functionality implemented by the MapWinGIS library. Water requirements and water footprints are assessed on a grid basis and can then be aggregated for spatial entities such as political boundaries, catchments or irrigation districts. We assume inefficient irrigation methods rather than optimal conditions to account for irrigation methods with efficiencies other than 100%. Furthermore, grey water is defined as the water needed to leach out salt from the rooting zone in order to maintain soil quality, an important management task in irrigation agriculture. Apart from a thorough representation of the modelling concept, we provide a proof of concept where we assess the agricultural water footprint of Saudi Arabia. The entire water footprint is 17.0 km3 yr-1 for 2008, with a blue water dominance of 86%. Using SPARE:WATER we are able to delineate regional hot spots as well as crop types with large water footprints, e.g. sesame or dates. Results differ from previous studies of national-scale resolution, underlining the need for regional estimation of crop water footprints.

  5. Instantaneous and daily values of the surface energy balance over agricultural fields using remote sensing and a reference field in an arid environment

    USGS Publications Warehouse

    Kustas, W.P.; Moran, M.S.; Jackson, R. D.; Gay, L.W.; Duell, L.F.W.; Kunkel, K.E.; Matthias, A.D.

    1990-01-01

    Remotely sensed surface temperature and reflectance in the visible and near infrared wavebands along with ancilliary meteorological data provide the capability of computing three of the four surface energy balance components (i.e., net radiation, soil heat flux, and sensible heat flux) at different spatial and temporal scales. As a result, under nonadvective conditions, this enables the estimation of the remaining term (i.e., the latent heat flux). One of the practical applications with this approach is to produce evapotranspiration (ET) maps for agricultural regions which consist of an array of fields containing different crops at varying stages of growth and soil moisture conditions. Such a situation exists in the semiarid southwest at the University of Arizona Maricopa Agricultural Center, south of Phoenix. For one day (14 June 1987), surface temperature and reflectance measurements from an aircraft 150 m above ground level (agl) were acquired over fields from zero to nearly full cover at four times between 1000 MST and 1130 MST. The diurnal pattern of the surface energy balance was measured over four fields, which included alfalfa at 60% cover, furrowed cotton at 20% and 30% cover, and partially plowed what stubble. Instantaneous and daily values of ET were estimated for a representative area around each flux site with an energy balance model that relies on a reference ET. This reference value was determined with remotely sensed data and several meteorological inputs. The reference ET was adjusted to account for the different surface conditions in the other fields using only remotely sensed variables. A comparison with the flux measurements suggests the model has difficulties with partial canopy conditions, especially related to the estimation of the sensible heat flux. The resulting errors for instantaneous ET were on the order of 100 W m-2 and for daily values of order 2 mm day-1. These findings suggest future research should involve development of methods to

  6. Investigation of greenhouse gas emissions from a landfill site and agriculture in the UK by deployment of an in-situ FTIR

    NASA Astrophysics Data System (ADS)

    Sonderfeld, Hannah; Humpage, Neil; Jeanjean, Antoine; Leigh, Roland; Allen, Grant; Boesch, Hartmut

    2016-04-01

    The main greenhouse gases (GHG) emitted by human activities in the UK are carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Understanding and quantifying their emissions is essential to monitor and guide emission reduction measures. The GAUGE (Greenhouse gAs Uk and Global Emissions) project funded by NERC aims to improve the knowledge of the UK GHG budget by an extensive measurement program. In this presentation, we focus on two important sources of these GHG: Waste and agricultural sector. We are presenting data from the deployment of an in-situ FTIR (Ecotech) for continuous and simultaneous sampling of CO2, CH4, N2O and CO with a high time resolution in the order of minutes. During a two week field campaign at a landfill site near Ipswich in August 2014, measurements were taken within a radius of 320 m of the uncovered and active area of the landfill, which was still filled with new incoming waste. The data are analysed in detail for emission ratios of CH4 to CO2. Thereby a consistent ratio in favour of CO2 is found for these emissions. We have applied a computation fluid dynamics (CFD) model, constrained with local wind measurements and a detailed topographic map of the landfill site, to the in-situ concentration data to calculate emission fluxes of the active site. Since October 2014 the FTIR has been sampling from a church tower in Glatton as part of a near surface sampling network in East Anglia focusing on regional GHG emissions from agriculture. The site is mainly influenced by south westerly winds. A clear diurnal cycle is observed in summer for CO2, CH4 and N2O, which is less pronounced in the winter months. A simulation of the methane and nitrous oxide concentrations through application of the NAME model to the EDGAR and NAEI emission inventories illustrates some shortcomings in the available emission inventories for the probed region.

  7. Nutrient uptake by agricultural crops from biochar-amended soils: results from two field experiments in Austria

    NASA Astrophysics Data System (ADS)

    Karer, Jasmin; Zehetner, Franz; Kloss, Stefanie; Wimmer, Bernhard; Soja, Gerhard

    2013-04-01

    The use of biochar as soil amendment is considered as a promising agricultural soil management technique, combining carbon sequestration and soil fertility improvements. These expectations are largely founded on positive experiences with biochar applications to impoverished or degraded tropical soils. The validity of these results for soils in temperate climates needs confirmation from field experiments with typical soils representative for intensive agricultural production areas. Frequently biochar is mixed with other organic additives like compost. As these two materials interact with each other and each one may vary considerably in its basic characteristics, it is difficult to attribute the effects of the combined additive to one of its components and to a specific physico-chemical parameter. Therefore investigations of the amendment efficacy require the study of the pure components to characterize their specific behavior in soil. This is especially important for adsorption behavior of biochar for macro- and micronutrients because in soil there are multiple nutrient sinks that compete with plant roots for vital elements. Therefore this contribution presents results from a field amendment study with pure biochar that had the objective to characterize the macro- and microelement uptake of crops from different soils in two typical Austrian areas of agricultural production. At two locations in North and South-East Austria, two identical field experiments on different soils (Chernozem and Cambisol) were installed in 2011 with varying biochar additions (0, 30 and 90 t/ha) and two nitrogen levels. The biochar was a product from slow pyrolysis of wood (SC Romchar SRL). During the installation of the experiments, the biochar fraction of <2 mm was mixed with surface soil to a depth of 15 cm in plots of 33 m2 each (n=4). Barley (at the Chernozem soil) and maize (at the Cambisol) were cultivated according to standard agricultural practices. The highest crop yields at both

  8. Utility of Thermal Image Sharpening for Monitoring Field-Scale Evapotranspiration over Rainfed and Irrigated Agricultural Regions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The utility of a thermal image sharpening algorithm (TsHARP) in providing fine resolution land surface temperature (LST) data to a Two-Source-Model (TSM) for mapping evapotranspiration (ET) was examined over two agricultural regions in the U.S. One site is in a rainfed corn and soybean production r...

  9. Dynamics of soil carbon, nitrogen and soil respiration in farmer’s field with conservation agriculture Siem Reap, Cambodia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The years of intensive tillage in many countries, including Cambodia, have caused significant decline in agriculture’s natural resources that could threaten the future of agricultural production and sustainability worldwide. Long-term tillage system and site-specific crop management can affect chang...

  10. EO-LDAS Temporal Regularization for Estimation of fAPAR over an Agriculture Test Site Using MISR Multiangular Information

    NASA Astrophysics Data System (ADS)

    Chernetskiy, M.; Gorbron, N.; Truckenbrodt, S.; Gomez-Dans, J.; Morgan, O.; Lewis, P.; Schmullius, C.

    2015-12-01

    In this study we present the retrieval of the Fraction of Photosynthetically Active Radiation (FAPAR) over an agricultural Sentinel-3 validation test site (S3VT) using multi-angular information from the Multiangle Imaging Spectroradiometer (MISR) at 275 m and the Earth Observation Land Data Assimilation System (EOLDAS). EO-LDAS is done with a temporal regularization using 7 MISR cameras. Results are compared against ground-based data, Joint Research Centre Two-stream Inversion Package (JRC-TIP) and Medium Resolution Imaging Spectrometer (MERIS) FAPAR products.

  11. Exposure to sulfosulfuron in agricultural drainage ditches: field monitoring and scenario-based modelling.

    PubMed

    Brown, Colin D; Dubus, Igor G; Fogg, Paul; Spirlet, Marie; Gustin, Christophe

    2004-08-01

    Field monitoring and scenario-based modelling were used to assess exposure of small ditches in the UK to the herbicide sulfosulfuron following transport via field drains. A site in central England on a high pH, clay soil was treated with sulfosulfuron, and concentrations were monitored in the single drain outfall and in the receiving ditch 1 km downstream. Drainflow in the nine months following application totalled 283 mm. Pesticide lost in the first 12.5 mm of flow was 99% of the total loading to drains (0.5% of applied). Significant dilution was observed in the receiving ditch and quantifiable residues were only detected in one sample (0.06 microg litre(-1)). The MACRO model was evaluated against the field data with minimal calibration. The parameterisation over-estimated the importance of macropore flow at the site. As a consequence, the maximum concentration in drainflow (2.3 microg litre(-1)) and the total loading to drains (0.76 g) were over-estimated by factors of 2.4 and 5, respectively. MACRO was then used to simulate long-term fate of the herbicide for each of 20 environmental scenarios. Resulting estimates for concentrations of sulfosulfuron in a receiving ditch were weighted according to the prevalence of each scenario to produce a probability distribution of daily exposure. PMID:15307668

  12. N-C isotopic investigation of a zeolite-amended agricultural field

    NASA Astrophysics Data System (ADS)

    Ferretti, Giacomo; Natali, Claudio; Faccini, Barbara; Di Giuseppe, Dario; Bianchini, Gianluca; Coltorti, Massimo

    2016-04-01

    In this study, a C and N isotopic investigation in the soil-plant system of the ZeoLIFE project experimental field have been carried out. Since many years, natural and NH4-enriched zeolites have been used as soil amendant in agricultural context in order to reduce N losses, increase NUE (Nitrogen Use Efficiency) and crop yield. Nevertheless up to now there are no studies that, using the stable isotopes approach, highlighted the interaction between zeolites and plants in agricultural systems. The main aims of this study is to verify if natural zeolites amendment can enhance chemical fertilization efficiency and if N transfer from NH4-enriched zeolites to plants really occurs. Plants grown following traditional cultivation methods (with no zeolite addition) and plants grown on soils amended with natural and NH4-enriched zeolites (the latter obtained after mixing with pig-slurry with a very high 15N) were compared for two cultivation cycles (maize and wheat). As widely known, plants grown under conventional farming systems (use of chemical fertilizers as urea) and plants grown under organic farming can be discriminated by the isotopic signatures of plant tissues. For both years the main results of the study reveals that plants grown on plots amended with natural zeolites generally have their nitrogen isotopic signature more similar to that of the chemical fertilizers employed during the cultivation with respect to the plants cultivated in the non-amended plot. This suggests an enhanced N uptake by the plant from this specific N source with respect to the non-amended plot. On the other hand, plants grown on NH4-enriched zeolites registered a higher 15N, approaching the pig-slurry isotopic signature, confirming that this material can constitute an N pool for plants at least for two cultivation cycles. The distinct agricultural practices seem to be reflected in the plant physiology as recorded by the carbon discrimination factor (13C) which generally increases

  13. Field and Wind Tunnel Comparison of Four Aerosol Samplers Using Agricultural Dusts

    PubMed Central

    Reynolds, Stephen J.; Nakatsu, Jason; Tillery, Marvin; Keefe, Thomas; Mehaffy, John; Thorne, Peter S.; Donham, Kelley; Nonnenmann, Matthew; Golla, Vijay; O'shaughnessy, Patrick

    2009-01-01

    Occupational lung disease is a significant problem among agricultural workers exposed to organic dusts. Measurements of exposure in agricultural environments in the USA have traditionally been conducted using 37-mm closed-face cassettes (CFCs) and respirable Cyclones. Inhalable aerosol samplers offer significant improvement for dose estimation studies to reduce respiratory disease. The goals of this study were to determine correction factors between the inhalable samplers (IOM and Button) and the CFC and Cyclone for dusts sampled in livestock buildings and to determine whether these factors vary among livestock types. Determination of these correction factors will allow comparison between inhalable measurements and historical measurements. Ten sets of samples were collected in swine, chicken, turkey, and dairy facilities in both Colorado and Iowa. Pairs of each sampling device were attached to the front and back of a rotating mannequin. Laboratory studies using a still-air chamber and a wind tunnel provided information regarding the effect of wind speed on sampler performance. Overall, the IOM had the lowest coefficient of variation (best precision) and was least affected by changes in wind speed. The performance of the Button was negatively impacted in poultry environments where larger (feather) particulates clogged the holes in the initial screen. The CFC/IOM ratios are important for comparisons between newer and older studies. Wind speed and dust type were both important factors affecting ratios. Based on the field studies (Table 6), a ratio of 0.56 is suggested as a conversion factor for the CFC/IOM (average for all environments because of no statistical difference). Suggested conversion factors for the Button/IOM are swine (0.57), chicken (0.80), turkey (0.53), and dairy (0.67). Any attempt to apply a conversion factor between the Cyclone and inhalable samplers is not recommended. PMID:19443852

  14. Anaerobic co-digestion plants for the revaluation of agricultural waste: Sustainable location sites from a GIS analysis.

    PubMed

    Villamar, Cristina Alejandra; Rivera, Diego; Aguayo, Mauricio

    2016-04-01

    The aim of this study was to establish sustainably feasible areas for the implementation of anaerobic co-digestion plants for agricultural wastes (cattle/swine slurries and cereal crop wastes). The methodology was based on the use of geographic information systems (GIS), the analytic hierarchy process (AHP) and map algebra generated from hedges related to environmental, social and economic constraints. The GIS model obtained was applied to a region of Chile (Bío Bío Region) as a case study showing the energy potential (205 MW-h) of agricultural wastes (swine/cattle manures and cereal crop wastes) and thereby assessing its energy contribution (3.5%) at country level (Chile). From this model, it was possible to spatially identify the influence of each factor (environmental, economic and social) when defining suitable areas for the siting of anaerobic co-digestion plants. In conclusion, GIS-based models establish appropriate areas for the location of anaerobic co-digestion plants in the revaluation of agricultural waste from the production of energy through biogas production. PMID:26862147

  15. Field-Scale Soil Moisture Observations in Irrigated Agriculture Fields Using the Cosmic-ray Neutron Rover

    NASA Astrophysics Data System (ADS)

    Franz, T. E.; Avery, W. A.; Finkenbiner, C. E.; Wang, T.; Brocca, L.

    2014-12-01

    Approximately 40% of global food production comes from irrigated agriculture. With the increasing demand for food even greater pressures will be placed on water resources within these systems. In this work we aimed to characterize the spatial and temporal patterns of soil moisture at the field-scale (~500 m) using the newly developed cosmic-ray neutron rover near Waco, NE. Here we mapped soil moisture of 144 quarter section fields (a mix of maize, soybean, and natural areas) each week during the 2014 growing season (May to September). The 11 x11 km study domain also contained 3 stationary cosmic-ray neutron probes for independent validation of the rover surveys. Basic statistical analysis of the domain indicated a strong inverted parabolic relationship between the mean and variance of soil moisture. The relationship between the mean and higher order moments were not as strong. Geostatistical analysis indicated the range of the soil moisture semi-variogram was significantly shorter during periods of heavy irrigation as compared to non-irrigated periods. Scaling analysis indicated strong power law behavior between the variance of soil moisture and averaging area with minimal dependence of mean soil moisture on the slope of the power law function. Statistical relationships derived from the rover dataset offer a novel set of observations that will be useful in: 1) calibrating and validating land surface models, 2) calibrating and validating crop models, 3) soil moisture covariance estimates for statistical downscaling of remote sensing products such as SMOS and SMAP, and 4) provide center-pivot scale mean soil moisture data for optimal irrigation timing and volume amounts.

  16. Agricultural terraces montoring and modeling: a field survey in Chianti region, Firenze, Italy - First part

    NASA Astrophysics Data System (ADS)

    Preti, Federico; Caruso, Marco; Dani, Andrea; Errico, Alessandro; Guastini, Enrico; Trucchi, Paolo

    2015-04-01

    The two abstracts present the design and set-up of an experimental field plant whose aim is the study and modeling of water circulation in a terraced slope together with its influence on the stability of the retaining dry stone walls. The pilot plant is located at "Fattoria di Lamole" (Greve in Chianti, Firenze, Italy) where both ancient and recently restored or rebuilt dry stone retaining walls are present. The intense vineyards cultivation makes it very representative in terms of range of external stresses that affect both hillslopes and walls. The research is developed within a bigger framework of landscape preservation as a way to prevent hydrogeological instabilities and landslide risks. First Part A first/preliminary field survey was carried out in order to estimate the hydraulic and mechanical soil characteristics. Field saturated hydraulic conductivity measurements with the Simplified Falling Head (SFH) method on a terrace along an alignment were performed. Infiltrometer tests with a double ring device and soil texture determinations with both fine particle-size and skeleton fraction distributions were also performed. The Direct shear test on undisturbed and reconstituted soil samples will offer an estimation of the Mohr-Coulomb failure envelope parameters (friction angle and cohesion). A reference portion of a dry stone wall will be also monitored. Lateral earth pressure at backfill-retaining wall interface (compared to temperature and air pressure measured values), backfill volumetric water content (both in saturated and unsaturated states) and ground-water level are measured. Acknowledgements Italian Research Project of Relevant Interest (PRIN2010-2011), prot. 20104ALME4, National network for monitoring, modeling, and sustainable management of erosion processes in agricultural land and hilly-mountainous area

  17. Improving Agricultural Drought Monitoring in East Africa with Unbiased Rainfall Fields and Detailed Land Surface Physics

    NASA Astrophysics Data System (ADS)

    McNally, A.; Yatheendradas, S.; Peters-Lidard, C. D.; Michaelsen, J.

    2010-12-01

    Monitoring drought is particularly challenging within rainfed agricultural and pastoral systems, where it can serve the greatest need. Such locations often have sparse or non-existent ground based measurements of precipitation, evapotranspiration (ET), and soil moisture. For more effective drought monitoring with limited hydroclimate observations, we simulate land surface states using the Community Noah Land Surface Model forced with different merged rainfall products inside a Land Information System (LIS). Using model outputs we will answer the questions: How sensitive are soil moisture and ET fields to differences in rainfall forcing and model physics? What are acceptable drought-specific tradeoffs between near-real time availability and skill of rainfall data? Preliminary results with the African Rainfall Estimation Algorithm Version 2 (RFE2.0) outperformed global products, suggesting that sub-global rainfall estimates are the way forward for regional drought monitoring. Specifically, the Noah model forced with RFE2.0 better resolved the heterogeneous patterns in crop stress than the Famine Early Warning System Network (FEWS NET) operational Water Requirement Satisfaction Index (WRSI) model. To further investigate the improvement in drought monitoring while maintaining timeliness, we unbias (using Africa specific climatology) the precipitation products from CPC Merged Analysis of Precipitation (CMAP), Tropical Rainfall Measurement Mission (TRMM), and RFE2.0. The skill (relative accuracy) and reliability (average agreement) of the unbiased rainfall are calculated against an unbiased precipitation product augmented with station data from Ethiopia and Kenya. Soil moisture and ET fields from Noah are compared to the operational FEWS NET WRSI, soil water anomaly index, and the World Food Program’s Crop and Food Security Assessment Mission reports. We anticipate that the unbiased rainfall fields will improve the accuracy, spatio-temporal resolution, and

  18. Nitrous oxide emission from an agricultural field fertilized with liquid lagoonal swine effluent

    NASA Astrophysics Data System (ADS)

    Whalen, S. C.; Phillips, R. L.; Fischer, E. N.

    2000-06-01

    Contemporary agriculture is characterized by the intensive production of livestock in confined facilities and land application of stored waste as an organic fertilizer. Emission of nitrous oxide (N2O) from receiving soils is an important but poorly constrained term in the atmospheric N2O budget. In particular, there are few data for N2O emissions from spray fields associated with industrial scale swine production facilities that have rapidly expanded in the southeastern United States. In an intensive, 24-day investigation over three spray cycles, we followed the time course for changes in N2O emission and soil physicochemical variables in an agricultural field irrigated with liquid lagoonal swine effluent. The total N (535 mg L-1) of the liquid waste was almost entirely NH4+-N (>90%) and thus had a low mineralization potential. Soil profiles for nitrification and denitrification indicated that >90% of potential activity was localized in the surface 20 cm. Application of this liquid fertilizer to warm (19° to 28°C) soils in a form that is both readily volatilized and immediately utilizable by the endogenous N-cycling microbial community resulted in a sharp decline in soil NH4+-N and supported a rapid but short-lived (i.e., days) burst of nitrification, denitrification, and N2O emission. Nitrous oxide fluxes as high as 9200 μg N2O-N m-2 h-1 were observed shortly after fertilization, but emissions decreased to prefertilization levels within a few days. Poor correlations between N2O efflux and soil physicochemical variables (temperature, moisture, NO3--N, NH4+-N) and fertilizer loading rate point to the complexity of interacting factors affecting N2O production and emission. Total fertilizer N applied and N2O-N emitted were 29.7 g m-2 (297 kg N ha-1) and 395 mg m-2, respectively. The fractional loss of applied N to N2O (corrected for background emission) was 1.4%, in agreement with the mean of 1.25% reported for mineral fertilizers. The direct effects of fertilizer

  19. Noncrop flowering plants restore top-down herbivore control in agricultural fields

    PubMed Central

    Balmer, Oliver; Pfiffner, Lukas; Schied, Johannes; Willareth, Martin; Leimgruber, Andrea; Luka, Henryk; Traugott, Michael

    2013-01-01

    Abstract Herbivore populations are regulated by bottom-up control through food availability and quality and by top-down control through natural enemies. Intensive agricultural monocultures provide abundant food to specialized herbivores and at the same time negatively impact natural enemies because monocultures are depauperate in carbohydrate food sources required by many natural enemies. As a consequence, herbivores are released from both types of control. Diversifying intensive cropping systems with flowering plants that provide nutritional resources to natural enemies may enhance top-down control and contribute to natural herbivore regulation. We analyzed how noncrop flowering plants planted as “companion plants” inside cabbage (Brassica oleracea) fields and as margins along the fields affect the plant–herbivore–parasitoid–predator food web. We combined molecular analyses quantifying parasitism of herbivore eggs and larvae with molecular predator gut content analysis and a comprehensive predator community assessment. Planting cornflowers (Centaurea cynanus), which have been shown to attract and selectively benefit Microplitis mediator, a larval parasitoid of the cabbage moth Mamestra brassicae, between the cabbage heads shifted the balance between trophic levels. Companion plants significantly increased parasitism of herbivores by larval parasitoids and predation on herbivore eggs. They furthermore significantly affected predator species richness. These effects were present despite the different treatments being close relative to the parasitoids’ mobility. These findings demonstrate that habitat manipulation can restore top-down herbivore control in intensive crops if the right resources are added. This is important because increased natural control reduces the need for pesticide input in intensive agricultural settings, with cascading positive effects on general biodiversity and the environment. Companion plants thus increase biodiversity both

  20. Maize production and land degradation: a Portuguese agriculture field case study

    NASA Astrophysics Data System (ADS)

    Ferreira, Carla S. S.; Pato, João V.; Moreira, Pedro M.; Valério, Luís M.; Guilherme, Rosa; Casau, Fernando J.; Santos, Daniela; Keizer, Jacob J.; Ferreira, António J. D.

    2016-04-01

    While food security is a main challenge faced by human kind, intensive agriculture often leads to soil degradation which then can threaten productivity. Maize is one of the most important crops across the world, with 869 million tons produced worldwide in 2012/2013 (IGC 2015), of which 929.5 thousand tons in Portugal (INE 2014). In Portugal, maize is sown in April/May and harvest occurs generally in October. Conventional maize production requires high inputs of water and fertilizers to achieve higher yields. As Portuguese farmers are typically rather old (on average, 63 years) and typically have a low education level (INE 2014), sustainability of their land management practises is often not a principal concern. This could explain why, in 2009, only 4% of the Portuguese temporary crops were under no-tillage, why only 8% of the farmers performed soil analyses in the previous three years, and why many soils have a low organic matter content (INE 2014). Nonetheless, sustainable land management practices are generally accepted to be the key to reducing agricultural soil degradation, preventing water pollution, and assuring long-term crop production objectives and food security. Sustainable land management should therefore not only be a concern for policy makers but also for farmers, since land degradation will have negative repercussions on the productivity, thus, on their economical income. This paper aims to assess the impact of maize production on soil properties. The study focusses on an 8 ha maize field located in central Portugal, with a Mediterranean climate on a gently sloping terrain (<3%) and with a soil classified as Eutric Fluvisol. On the field, several experiments were carried out with different maize varieties as well as with different fertilizers (solid, liquid and both). Centre pivot irrigation was largely used. Data is available from 2003, and concerns crop yield, fertilization and irrigation practices, as well as soil properties assessed through

  1. Nanotechnologies in agriculture and food - an overview of different fields of application, risk assessment and public perception.

    PubMed

    Grobe, Antje; Rissanen, Mikko E

    2012-12-01

    Nanomaterials in agriculture and food are key issues of public and regulatory interest. Over the past ten years, patents for nanotechnological applications in the field of food and agriculture have become abundant. Uncertainty prevails however regarding their current development status and presence in the consumer market. Thus, the discussion on nanotechnologies in the food sector with its specific public perception of benefits and risks and the patterns of communication are becoming similar to the debate on genetically modified organisms. The food industry's silence in communication increased mistrust of consumer organisations and policy makers. The article discusses the background of the current regulatory debates, starting with the EU recommendation for defining nanomaterials, provides an overview of possible fields of application in agriculture and food industries and discusses risk assessment and the public debate on benefits and risks. Communicative recommendations are directed at researchers, the food industry and regulators in order to increase trust both in stakeholders, risk management and regulatory processes. PMID:23013411

  2. Intensive field measurements of nitrous oxide emissions from a tropical agricultural soil

    NASA Astrophysics Data System (ADS)

    Crill, P. M.; Keller, M.; Weitz, A.; Grauel, B.; Veldkamp, E.

    2000-03-01

    The amount of nitrous oxide (N2O) continues to increase in the atmosphere. Agricultural use of nitrogen fertilizers in the tropics is thought to be an important source of atmospheric N2O. High frequency, highly precise measurements of the N2O flux were made with an automated system deployed in N fertilized and unfertilized agricultural plots of papaya and corn in Costa Rica for an entire corn crop growth to harvest cycle. N2O fluxes were as high as 64 ng N-N2O cm-2 h-1 from fertilized versus 12 ng N-N2O cm-2 h-1 from unfertilized corn and 28 ng N-N2O cm-2 h-1 from fertilized versus 4.6 ng N-N2O cm-2 h-1 from unfertilized papaya. Fertilized corn released more N2O than fertilized papaya over the 125 days of the crop cycle, 1.83 kg N ha-1 versus 1.37 kg N ha-1. This represents a loss as N2O of 1.1 and 0.9% of the total N applied as ammonium nitrate to the corn and papaya, respectively. As has often been observed, N2O fluxes were highly variable. The fastest rates of emission were associated with fertilization and high soil moisture. A diurnal cycle in the fluxes was not evident probably due to the minimal day/night temperature fluctuations. Each chamber was measured between 509 and 523 times over the course of the experiment. This allows us to evaluate the effect on constructed mean fluxes of lowered sampling frequencies. Sampling each collar about once a day throughout the crop cycle (25% of the data set) could result in a calculated mean flux from any individual chamber that can vary by as much as 20% even though the calculated mean would probably be within 10% of the mean of the complete data set. The uncertainty increases very rapidly at lower sampling frequencies. For example, if only 10% of the data set were used which would be the equivalent of sampling every other day, a very high sampling frequency in terms of manual measurements, the calculated mean flux could vary by as much as 40% or more at any given site.

  3. Spatial probability of soil water repellency in an abandoned agricultural field in Lithuania

    NASA Astrophysics Data System (ADS)

    Pereira, Paulo; Misiūnė, Ieva

    2015-04-01

    Water repellency is a natural soil property with implications on infiltration, erosion and plant growth. It depends on soil texture, type and amount of organic matter, fungi, microorganisms, and vegetation cover (Doerr et al., 2000). Human activities as agriculture can have implications on soil water repellency (SWR) due tillage and addition of organic compounds and fertilizers (Blanco-Canqui and Lal, 2009; Gonzalez-Penaloza et al., 2012). It is also assumed that SWR has a high small-scale variability (Doerr et al., 2000). The aim of this work is to study the spatial probability of SWR in an abandoned field testing several geostatistical methods, Organic Kriging (OK), Simple Kriging (SK), Indicator Kriging (IK), Probability Kriging (PK) and Disjunctive Kriging (DK). The study area it is located near Vilnius urban area at (54 49' N, 25 22', 104 masl) in Lithuania (Pereira and Oliva, 2013). It was designed a experimental plot with 21 m2 (07x03 m). Inside this area it was measured SWR was measured every 50 cm using the water drop penetration time (WDPT) (Wessel, 1998). A total of 105 points were measured. The probability of SWR was classified in 0 (No probability) to 1 (High probability). The methods accuracy was assessed with the cross validation method. The best interpolation method was the one with the lowest Root Mean Square Error (RMSE). The results showed that the most accurate probability method was SK (RMSE=0.436), followed by DK (RMSE=0.437), IK (RMSE=0.448), PK (RMSE=0.452) and OK (RMSE=0.537). Significant differences were identified among probability tests (Kruskal-Wallis test =199.7597 p<0.001). On average the probability of SWR was high with the OK (0.58±0.08) followed by PK (0.49±0.18), SK (0.32±0.16), DK (0.32±0.15) and IK (0.31±0.16). The most accurate probability methods predicted a lower probability of SWR in the studied plot. The spatial distribution of SWR was different according to the tested technique. Simple Kriging, DK, IK and PK methods

  4. The full GHG balance over two crop rotations at an agricultural site near Gebesee, Thuringia, Germany

    NASA Astrophysics Data System (ADS)

    Kutsch, Werner Leo; Brümmer, Christian; Don, Catharina; Dechow, Rene; Fuß, Roland; Freibauer, Annette; Schulze, Ernst-Detlef; Kolle, Olaf; Ziegler, Waldemar

    2013-04-01

    Gebesee in Thuringia is the eldest cropland eddy covariance (EC) site in Europe. The site has been part of CarboEurope, NitroEurope and IMECC and has been selected to be one of the German Level 1 sites within the European research infrastructure ICOS. Continuous measurements of NEE by EC, NPP by regular harvesting, lateral in- and outputs of carbon and nitrogen as well as climatic parameters have been conducted since 2001. Automated chamber measurements of N2O and CH4 were conducted since 2007. Fluxes of these greenhouse gases (GHG) for the years 2001 - 2006 were calculated based on a Fuzzy Logic model calibrated by means of the chamber measurements. In this study we present NEE, NBP and full GHG balances of over two rotation periods (2001 - 2004 and 2005 - 2009, respectively) comprising four times winter wheat, two times potatoes and one cropping period of oil seed rape, sugar beet and barley each. The GHG balance is dominated by moderate losses of soil organic matter (~120 +/- 50 g C m-2 y-1) and by N2O emissions of about 0.17 g N2O-N m-2 y-1 (50 g C-eq m-2 y-1). The on-site emissions of GHG balance about 43 % of the harvested carbon.

  5. Development of a field worthy sensor system to monitor gaseous nitrogen transfer from agricultural cropland

    SciTech Connect

    Not Available

    1992-11-01

    Nitrogen fertilizer accounts for 25 to 33% of the energy requirements in modern crop agriculture in the world today. Energy input for the manufacture of these N fertilizers is in the range of 460 [times] 10[sup 12] Btu per year. Unfortunately, for some N sources up to 70% of this energy in the form of NK can be lost through improper application techniques and poor N management strategies. Anhydrous NH[sub 3] may be lost to the atmosphere during and after placement due to soil conditions placement. Measurement of volatile N is difficult, especially under field conditions. A precise and convenient method of measuring gaseous NH[sub 3] near and above the soil surface is prerequisite to the development and evaluation of altemative fertilizer management strategies and application techniques which can reduce the potential for significant loss. Recent advances in integrated-optic (IO) based sensing offers the potential of measuring low levels of NH[sub 3] loss from a cropping system in the range of 100 ppB. The integrated design of an IO system allows for a more durable device that can be mass produced at low cost. Under Phase I of this project, two IO devices were designed and tested: an absorption device using an oxazine dye as a waveguide coating and an interferometric device using an anilinium salt as a waveguide coating.

  6. Molecular properties of a fermented manure preparation used as field spray in biodynamic agriculture.

    PubMed

    Spaccini, R; Mazzei, P; Squartini, A; Giannattasio, M; Piccolo, A

    2012-11-01

    Manure products fermented underground in cow horns and commonly used as field spray (preparation 500) in the biodynamic farming system, were characterized for molecular composition by solid-state nuclear magnetic resonance [(13) C cross-polarization magic-angle-spinning NMR ((13) C-CPMAS-NMR)] spectroscopy and offline tetramethylammonium hydroxide thermochemolysis gas chromatography-mass spectrometry. Both thermochemolysis and NMR spectroscopy revealed a complex molecular structure, with lignin aromatic derivatives, polysaccharides, and alkyl compounds as the predominant components. CPMAS-NMR spectra of biodynamic preparations showed a carbon distribution with an overall low hydrophobic character and significant contribution of lignocellulosic derivatives. The results of thermochemolysis confirmed the characteristic highlighted by NMR spectroscopy, revealing a molecular composition based on alkyl components of plant and microbial origin and the stable incorporation of lignin derivatives. The presence of biolabile components and of undecomposed lignin compounds in the preparation 500 should be accounted to its particularly slow maturation process, as compared to common composting procedures. Our results provide, for the first time, a scientific characterization of an essential product in biodynamic agriculture, and show that biodynamic products appear to be enriched of biolabile components and, therefore, potentially conducive to plant growth stimulation. PMID:22707205

  7. Nitrogen Cycle Modeling: a Mechanistic Estimate of N-losses From Agricultural Fields Over the Seasonal Time Period

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The biogeochemical cycle of nitrogen and production of NO, N2O, and CO2 gas and NO2- and NO3- ions in nutrient-enriched agricultural fields is mediated by soil microbial activity, the hydrological cycle, plant dynamics, and climatic forcing. Understanding how NO, N2O, CO2 gases and NO2- and NO3- io...

  8. Evaluating Ditch Drainage Control Structure for Mitigating Export of Nitrogen from Agricultural Fields in the Choptank River Watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Choptank River watershed has an extensive network of agricultural drainage ditches that are significant pathways of nitrogen export from production fields and negatively impact water quality in the Chesapeake Bay. The use of controlled drainage structures on ditches to regulate water flow has b...

  9. THE USE OF CHEMICALS IN THE FIELD OF FARM ANIMAL HEALTH (NUTRITION, ENTOMOLOGY, PATHOLOGY). AGRICULTURAL CHEMICALS TECHNOLOGY, NUMBER 7.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center for Vocational and Technical Education.

    DEVELOPED BY A NATIONAL TASK FORCE ON THE BASIS OF STATE STUDIES, THIS MODULE IS ONE OF A SERIES DESIGNED TO ASSIST TEACHERS IN PREPARING POST-SECONDARY STUDENTS FOR AGRICULTURAL CHEMICAL OCCUPATIONS. THE SPECIFIC OBJECTIVE OF THIS MODULE IS TO PREPARE TECHNICIANS IN THE FIELD OF THE USE OF CHEMICALS FOR ANIMAL HEALTH. SECTIONS INCLUDE -- (1)…

  10. Designing experiments to evaluate the effectiveness of precision agricultural practices on research fields. Part 1. Concepts for formulation.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this paper is to present a unique formulation methodology for designing experiments to evaluate the effectiveness of a precision agricultural practice on a research farm field. We demonstrate an efficient method of combining the georeferenced treatment structure and the georeferenc...

  11. Estimation of decay rates for fecal indicator bacteria and bacterial pathogens in agricultural field-applied manure

    EPA Science Inventory

    Field-applied manure is an important source of pathogenic exposure in surface water bodies for humans and ecological receptors. We analyzed the persistence and decay of fecal indicator bacteria and bacterial pathogens from three sources (cattle, poultry, swine) for agricultural f...

  12. Field-based evaluation tool for riparian buffer zones in agricultural catchments.

    PubMed

    Ducros, Caroline M J; Joyce, Chris B

    2003-08-01

    Riparian buffer zones can improve water quality and enhance habitat, but a comprehensive yet rapid method that can assist the resource manager in assessing the effectiveness of buffers is not available. The aim of this paper is to describe and illustrate the use of a newly developed field-based evaluation tool for riparian buffer zones in agricultural catchments. The Buffer Zone Inventory and Evaluation Form (BZIEF) incorporates criteria-based scoring systems developed from literature review, subsequent peer-review, and then a pilot field study. Use of the BZIEF is demonstrated by comparing buffer zones in three catchments established for water quality and habitat improvement under the Water Fringe Option agrienvironment scheme in England in order to assess whether the buffers were likely to provide environmental enhancement. Results among the three catchments were generally similar; buffer zones scored highly for their abundant vegetation cover, lack of erosion, stream habitat quality, and sufficient width. Furthermore, previous grassland or arable land use did not substantially affect buffer zone ratings. However, the BZIEF indicated that inappropriate soil characteristics in one catchment were likely to constrain buffer zone effectiveness for improving water quality. In another catchment, poor riparian vegetation diversity and structure may yield ineffective habitat enhancement, according to the BZIEF. It was concluded that the BZIEF might be a useful tool for buffer zone comparison and monitoring, even though more work is needed to test and validate the method. For example, the BZIEF could be used to target appropriate locations for buffer zones and is flexible, so could be adapted for different policies, objectives and regions. PMID:14753650

  13. Fluxes of Nitrous Acid (HONO) above an Agricultural Field Side near Paris

    NASA Astrophysics Data System (ADS)

    Laufs, S.; Cazaunau, M.; Stella, P.; Loubet, B.; Kurtenbach, R.; Cellier, P.; Mellouki, W.; Kleffmann, J.

    2012-04-01

    HONO is an important precursor of the OH radical, the detergent of the atmosphere. Field measurements show high diurnal HONO mixing ratios that cannot be explained by chemical models with known gas phase chemistry. Therefore, daytime sources of HONO are still under discussion. During the last decade many experimental investigation were performed to study heterogeneous production of HONO like the photo enhanced reduction of NO2 on humic acids or photolysis of HNO3 on surfaces. Recently, nitrite produced by bacteria, present in soil, was discussed as a source of HONO as well. In addition gas phase sources like the photolysis of nitrophenols, or the reaction of excited NO2 are discussed. Gradient measurements show high mixing ratios of HONO even above the boundary layer. However, beside intensive investigations on the sources of HONO, it is still an open question whether heterogeneous or gas phase sources are more important in the atmosphere. Flux measurements could represent a method to find the origin of missing sources of HONO. Until now instruments are not sensitive and fast enough to do Eddy correlation measurements for HONO. Alternatively, HONO fluxes are estimated by the Aerodynamic Gradient (AGM), or Relaxed Eddy Accumulation (REA) methods. Here we present HONO fluxes estimated by AGM and the LOPAP technique (Long Path Absorption Photometer) above an agricultural field in Grignon, Paris (48°51'N, 1°58'E). Fluxes during different seasons and different types of vegetations including bare soil will be presented and compared with chemical corrected fluxes of NO, NO2 and O3, or other parameters.

  14. Testing the Need for Replication of Eddy Covariance Carbon Dioxide Flux Measurements over Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Taylor, A. M.; Amiro, B. D.; Gervais, M.

    2015-12-01

    The eddy covariance method directly measures carbon dioxide (CO2) fluxes for long periods of time and with footprints up to hundreds of meters in size. Any ecosystem process that alters how gases and energy move between the atmosphere and soil/vegetation can affect these fluxes. Eddy covariance is vulnerable to systematic errors and uncertainy, particular through relying on assumptions about surface characteristics. Additionally, spatial variation within a site can cause more uncertainty in these measurements and lack of replication in many eddy covariance studies makes statistical analysis of carbon fluxes challenging. We tested if there are significant differences between co-located and simultaneous CO2 flux measurements over a uniform crop surface, and if the differences increase if we measure different flux footprint areas over the same field. During the summer of 2014, three matched instrumented 2.5-m high towers were co-located and then periodically separated by moving at 50 m intervals along a north-south transect on an alfalfa/trefoil field and a spring wheat field in Southern Manitoba, Canada to compare CO­2 fluxes. Georeferenced leaf area index measurements were taken in 50 m grid of each field to establish uniformity of the source/sink within a footprint. Diurnal differences of similar magnitude in the CO2 ­fluxes were found in both the co-located experiment and the spatially separated intervals. Despite rigorous calibration during the experiment, some differences were caused by the measurement systems rather than by variation within the field. Interpretation of the spatial variation in leaf area index is being used to determine the contribution caused by difference in source/sink contributions to the flux footprint areas when the towers were spatially separated.

  15. Far-Field Rock Size-Frequency Distribution at the Mars Pathfinder Landing Site and Comparison to the Near Field

    NASA Technical Reports Server (NTRS)

    Haldemann, A. F. C.; Forsberg, N. K.; Golombek, M. P.; Bridges, N. T.

    2000-01-01

    Detailed measurements of rocks in the far field at the Mars Pathfinder landing site are consistent with the near field exponential drop off in the cumulative number or area covered by large diameter rocks (and with similar behavior at the Viking sites).

  16. Seasonal OVOC fluxes from an agricultural field planted with sugar beet

    NASA Astrophysics Data System (ADS)

    Custer, T. G.; Schade, G. W.

    2005-12-01

    Although agricultural crops are generally not strong isoprenoid emitters, they do emit a variety of other atmospherically significant species collectively known as oxygenated VOCs (OVOCs), such as methanol, acetaldehyde, or various hexenal and hexenol compounds. Many OVOCs have longer atmospheric lifetimes than isoprenoid compounds and can affect the atmosphere's oxidative potential at higher elevations and far from sources. We performed selected OVOC flux measurements for select species above an agricultural field planted with sugar beets ( B. vulgaris) in northern Germany in 2004 to better understand the magnitude and controls over these OVOC emissions. Virtual disjunct eddy covariance was used to measure fluxes beginning immediately following seeding and continuing until past harvest. A commercial PTR-MS provided mixing ratios of methanol (m/z 33), acetaldehyde (m/z 45), acetone (m/z 59), and the sum of the isoprene oxidation products methacrolein and methyl vinyl ketone (m/z 71) while 3D wind velocities were measured using a Gill R3 sonic anemometer. Here, we compare the fluxes of methanol and acetone over the growth cycle of sugar beet to plant development as measured by the leaf area index. Methanol fluxes ranged from approximately -0.05 to 0.15 mg C m-2 h-1 (mixing ratios from ~1 to 15 ppbv) and showed a clear diurnal cycle after the sugar beets established a significant leaf area. Acetone fluxes ranged from approximately -0.2 to 0.2 mg C m-2 h-1 (mixing ratios from ~0.2 to 3 ppb). Higher specific emissions were found during earlier growth stages. Methanol flux correlated strongly with latent heat flux (or alternatively, with canopy conductance derived from the latent heat flux), while acetone flux did not. Acetone flux was small compared to methanol flux and sugar beet is likely not a significant acetone emitter. Weekly measurements of soil OVOC exchange using a flux chamber showed that the soil may have contributed significantly to the overall flux values

  17. Organic particulate emissions from field burning of garden and agriculture residues

    NASA Astrophysics Data System (ADS)

    Gonçalves, Cátia; Evtyugina, Margarita; Alves, Célia; Monteiro, Cristina; Pio, Casimiro; Tomé, Mário

    2011-08-01

    To assess the particulate matter (PM) composition, the smoke from three different agriculture and garden residues, commonly subjected to open field burning in Northern Portugal (potato haulm (A), arable weed vegetation (B) and collard greens stalks/pruned green leafy-twigs (C)) have been sampled into 3 different size fractions (PM 2.5, PM 2.5-10 and PM > 10 ). To replicate another frequent practise of reducing or dispose agriculture/garden debris, residue C was complementarily burned in a metal container with addition of used lubricant oil. The size-segregated aerosol samples were analysed for elemental (EC) and organic (OC) carbon by a thermal-optical transmission technique. The organosoluble OC was fractionated by vacuum flash chromatography and analysed by gas chromatography-mass spectrometry (GC-MS). Burning of residue C produced the highest PM emissions. OC was the dominant carbonaceous component in all aerosol samples, contributing to about 98% of total carbon (TC). The detailed chemical profiles of particulate emissions, including organic tracer compounds, have been assessed. The contribution of phenolics (0.2-39% OC, w/w) and organic acids (1.5-13% OC, w/w) to OC was always predominant over other organic compounds, whose distribution patterns were found to vary from one residue to another. The polyphenols, as the guaiacyl derivatives, were particularly abundant in PM from the residue C burning, but anthropogenic constituents completely superimposed the emission profiles after addition of used lubricant oil. It was shown that the prevailing ambient conditions (such as high humidity) likely contributed to atmospheric processes (e.g. coagulation and hygroscopic growth), which influenced the particle size characteristics of the smoke tracers, shifting their distribution to larger diameters. Since it was shown that the relative contribution of different carbon forms and organic compounds may strongly depend on the size of the particulate matter, the barely

  18. Production and conservation results from a decade-long field-scale precision agriculture system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research is needed that simultaneously evaluates production and conservation outcomes of precision agriculture practices. From over a decade (1993-2003) of yield and soil mapping and water quality assessment, a multi-faceted, “precision agriculture system” (PAS) was developed and initiated in 2004 o...

  19. Agricultural terraces montoring and modeling: a field survey in Chianti region, Firenze, Italy – Second part

    NASA Astrophysics Data System (ADS)

    Preti, Federico; Caruso, Marco; Dani, Andrea; Cassiani, Giorgio; Romano, Nunzio; Tarolli, Paolo

    2015-04-01

    The two abstracts present the design and set-up of an experimental campaign which aims at sup-porting the modeling (conceptual and numerical) of water circulation in a terraced slope, and its in-fluence on stability of retaining dry stone walls. The case study is located at "Fattoria di Lamole" (Greve in Chianti, Firenze, Italy). At Lamole site both ancient and recently restored or rebuilt (with different techniques) dry stone walls are present. Furthermore the intense vineyards cultivation makes it very representative in terms of range of external stresses that affect both hillslopes and wall. The survey is developed within the bigger framework of landscape preservation as a way to prevent hydrogeological instabilities and landslide risks. Second Part A second effort is devoted to couple hydrological, hydraulic and geotechnical modeling: - Flow directions and the drainage area have been derived from DTM (high-resolution digital terrain model obtained by a terrestrial laser scanner.), and served for the RPII index calcula-tion (Tarolli et al., 2013), that is coherent with the critical spots observed in situ and marked with GPS. - Direct shear test on undisturbed and reconstituted soil samples will offer an estimation of the Mohr-Coulomb failure envelope parameters (friction angle and cohesion). - Retention curves related with different depths have been derived. - Geoelectric analysis in order to locate the bedrock and to determine the subterranean water flows originated from controlled infitration tests (1 l/s discharge). - A simple dry-wall stability model has been carried out; this model analyses the wall stability with finite elements method, evaluating pressures derived from uphill water infiltration, stone friction and buoyancy in retaining wall layers: simulated deformation are suitable with the observed ones. Acknowledgements Italian Research Project of Relevant Interest (PRIN2010-2011), prot. 20104ALME4, National network for monitoring, modeling, and

  20. Could crop height affect the wind resource at agriculturally productive wind farm sites?

    SciTech Connect

    Vanderwende, Brian; Lundquist, Julie K.

    2015-11-07

    The collocation of cropland and wind turbines in the US Midwest region introduces complex meteorological interactions that could influence both agriculture and wind-power production. Crop management practices may affect the wind resource through alterations of land-surface properties. We use the weather research and forecasting (WRF) model to estimate the impact of crop height variations on the wind resource in the presence of a large turbine array. A hypothetical wind farm consisting of 121 1.8-MW turbines is represented using the WRF model wind-farm parametrization. We represent the impact of selecting soybeans rather than maize by altering the aerodynamic roughness length in a region approximately 65 times larger than that occupied by the turbine array. Roughness lengths of 0.1 and 0.25 m represent the mature soy crop and a mature maize crop, respectively. In all but the most stable atmospheric conditions, statistically significant hub-height wind-speed increases and rotor-layer wind-shear reductions result from switching from maize to soybeans. Based on simulations for the entire month of August 2013, wind-farm energy output increases by 14 %, which would yield a significant monetary gain. Further investigation is required to determine the optimal size, shape, and crop height of the roughness modification to maximize the economic benefit and minimize the cost of such crop-management practices. As a result, these considerations must be balanced by other influences on crop choice such as soil requirements and commodity prices.

  1. Could Crop Height Affect the Wind Resource at Agriculturally Productive Wind Farm Sites?

    NASA Astrophysics Data System (ADS)

    Vanderwende, Brian; Lundquist, Julie K.

    2016-03-01

    The collocation of cropland and wind turbines in the US Midwest region introduces complex meteorological interactions that could influence both agriculture and wind-power production. Crop management practices may affect the wind resource through alterations of land-surface properties. We use the weather research and forecasting (WRF) model to estimate the impact of crop height variations on the wind resource in the presence of a large turbine array. A hypothetical wind farm consisting of 121 1.8-MW turbines is represented using the WRF model wind-farm parametrization. We represent the impact of selecting soybeans rather than maize by altering the aerodynamic roughness length in a region approximately 65 times larger than that occupied by the turbine array. Roughness lengths of 0.1 and 0.25 m represent the mature soy crop and a mature maize crop, respectively. In all but the most stable atmospheric conditions, statistically significant hub-height wind-speed increases and rotor-layer wind-shear reductions result from switching from maize to soybeans. Based on simulations for the entire month of August 2013, wind-farm energy output increases by 14 %, which would yield a significant monetary gain. Further investigation is required to determine the optimal size, shape, and crop height of the roughness modification to maximize the economic benefit and minimize the cost of such crop-management practices. These considerations must be balanced by other influences on crop choice such as soil requirements and commodity prices.

  2. Estimation of Soil Erosion by Using Magnetic Method: A Case Study of an Agricultural Field in Southern Moravia (Czech Republic)

    NASA Astrophysics Data System (ADS)

    Petrovsky, E.; Grison, H.; Kapicka, A.; Dlouha, S.; Kodesova, R.; Jaksik, O.

    2013-05-01

    In this study we have applied magnetism of soils for estimation of erosion at an agricultural land. The testing site is situated in loess region in Southern Moravia (in Central Europe). The approach is based on well-established method of differentiation of magnetic parameters of the topsoil and the subsoil horizons as a result of in situ formation of strongly magnetic iron oxides. Our founding is established on a simple tillage homogenization model described by Royall (2001) using magnetic susceptibility and its frequency dependence to estimate soil loss caused by the tillage and subsequent erosion. The original dominant Soil Unit in the investigated area is Haplic Chernozem, which is due to intensive erosion progressively transformed into different Soil Units. The site is characterized by a flat upper part while the middle part, formed by a substantive side valley, is steeper (up to 15°). The side valley represents a major line of concentrated runoff emptying into a colluvial fan. Field measurements of the topsoil volume magnetic susceptibility were carried out by the Bartington MS2D probe. Data are resulting in regular grid of 101 data points, where the bulk soil material was gathered for further laboratory investigations. Moreover, vertical distribution of magnetic susceptibility (deep to 40 cm) was measured on selected transects using the SM400 kappameter. In the laboratory, after drying and sieving of collected soil samples, mass-specific magnetic susceptibility and its frequency-dependent susceptibility was measured. In order to identify magnetic minerals the thermomagnetic analyses were performed using the AGICO KLY-4S Kappabridge with CS-3 furnace. Hysteresis loops were carried out on vibrating magnetometer ADE EV9 to assess the grain-size distribution of ferrimagnetic particles. Hereafter, the isothermal remanent magnetization acqusition followed by D.C. demagnetization were done. All these laboratory magnetic measurements were performed in order to

  3. Field Summary Report for Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington

    SciTech Connect

    L.C. Hulstrom

    2010-08-11

    This report summarizes field sampling activities conducted in support of WCH’s Remedial Investigation of Hanford Site Releases to the Columbia River. This work was conducted form 2008 through 2010. The work included preliminary mapping and measurement of Hanford Site contaminants in sediment, pore water, and surface water located in areas where groundwater upwelling were found.

  4. Field Summary Report for Remedial Investigation of Hanford Site Releases to the Coumbia River, Hanford Site, Washington

    SciTech Connect

    L.C. Hulstrom

    2010-11-10

    This report summarizes field sampling activities conducted in support of WCH’s Remedial Investigation of Hanford Site Releases to the Columbia River. This work was conducted form 2008 through 2010. The work included preliminary mapping and measurement of Hanford Site contaminants in sediment, pore water, and surface water located in areas where groundwater upwelling were found.

  5. Are BVOC exchanges in agricultural ecosystems overestimated? Insights from fluxes measured in a maize field over a whole growing season

    NASA Astrophysics Data System (ADS)

    Bachy, Aurélie; Aubinet, Marc; Schoon, Niels; Amelynck, Crist; Bodson, Bernard; Moureaux, Christine; Heinesch, Bernard

    2016-04-01

    Maize is the most important C4 crop worldwide. It is also the second most important crop worldwide (C3 and C4 mixed), and is a dominant crop in some world regions. Therefore, it can potentially influence local climate and air quality through its exchanges of gases with the atmosphere. Among others, biogenic volatile organic compounds (BVOC) are known to influence the atmospheric composition and thereby modify greenhouse gases lifetime and pollutant formation in the atmosphere. However, so far, only two studies have dealt with BVOC exchanges from maize. Moreover, these studies were conducted on a limited range of meteorological and phenological conditions, so that the knowledge of BVOC exchanges by this crop remains poor. Here, we present the first BVOC measurement campaign performed at ecosystem-scale on a maize field during a whole growing season. It was carried out in the Lonzée Terrestrial Observatory (LTO), an ICOS site. BVOC fluxes were measured by the disjunct by mass-scanning eddy covariance technique with a proton transfer reaction mass spectrometer for BVOC mixing ratios measurements. Outstanding results are (i) BVOC exchanges from soil were as important as BVOC exchanges from maize itself; (ii) BVOC exchanges observed on our site were much lower than exchanges observed by other maize studies, even under normalized temperature and light conditions, (iii) they were also lower than those observed on other crops grown in Europe. Lastly (iv), BVOC exchanges observed on our site under standard environmental conditions, i.e., standard emission factors SEF, were much lower than those currently considered by BVOC exchange up-scaling models. From those observations, we deduced that (i) soil BVOC exchanges should be better understood and should be incorporated in terrestrial BVOC exchanges models, and that (ii) SEF for the C4 crop plant functional type cannot be evaluated at global scale but should be determined for each important agronomic and pedo-climatic region

  6. Kd Values for Agricultural and Surface Soils for Use in Hanford Site Farm, Residential, and River Shoreline Scenarios

    SciTech Connect

    Serne, R. Jeffrey

    2007-08-01

    This report provides best estimate Kd values and a minimum and maximum range of Kd values to be used for agricultural soils and Columbia River bank sediments that exist today or would exist in the future when portions of the Hanford Site are released for farming, residential, and recreational use after the U. S. Department of Energy (DOE) completes clean up of defense waste on the site. The Kd values should be used to determine the fate and transport rates of contaminants and their availability for plant and animal uptake in selected non-groundwater scenarios included in Hanford Site environmental impact statements, risk assessments and specific facility performance assessments. This report describes scenarios such as a small farm where drilling of a well inadvertently goes through buried waste and brings waste to the surface, allowing the tailings to become available for direct human exposure or incorporation into garden crops and farm animals used for food by the farm family. The Kd values recommended in this report can also be used to calculate sediment-water partitioning factors used to predict plant and animal uptake from interaction with the contaminated soil.

  7. Automatic Training Site Selection for Agricultural Crop Classification: a Case Study on Karacabey Plain, Turkey

    NASA Astrophysics Data System (ADS)

    Ozdarici Ok, A.; Akyurek, Z.

    2011-09-01

    This study implements a traditional supervised classification method to an optical image composed of agricultural crops by means of a unique way, selecting the training samples automatically. Panchromatic (1m) and multispectral (4m) Kompsat-2 images (July 2008) of Karacabey Plain (~100km2), located in Marmara region, are used to evaluate the proposed approach. Due to the characteristic of rich, loamy soils combined with reasonable weather conditions, the Karacabey Plain is one of the most valuable agricultural regions of Turkey. Analyses start with applying an image fusion algorithm on the panchromatic and multispectral image. As a result of this process, 1m spatial resolution colour image is produced. In the next step, the four-band fused (1m) image and multispectral (4m) image are orthorectified. Next, the fused image (1m) is segmented using a popular segmentation method, Mean- Shift. The Mean-Shift is originally a method based on kernel density estimation and it shifts each pixel to the mode of clusters. In the segmentation procedure, three parameters must be defined: (i) spatial domain (hs), (ii) range domain (hr), and (iii) minimum region (MR). In this study, in total, 176 parameter combinations (hs, hr, and MR) are tested on a small part of the area (~10km2) to find an optimum segmentation result, and a final parameter combination (hs=18, hr=20, and MR=1000) is determined after evaluating multiple goodness measures. The final segmentation output is then utilized to the classification framework. The classification operation is applied on the four-band multispectral image (4m) to minimize the mixed pixel effect. Before the image classification, each segment is overlaid with the bands of the image fused, and several descriptive statistics of each segment are computed for each band. To select the potential homogeneous regions that are eligible for the selection of training samples, a user-defined threshold is applied. After finding those potential regions, the

  8. Could crop height affect the wind resource at agriculturally productive wind farm sites?

    DOE PAGESBeta

    Vanderwende, Brian; Lundquist, Julie K.

    2015-11-07

    The collocation of cropland and wind turbines in the US Midwest region introduces complex meteorological interactions that could influence both agriculture and wind-power production. Crop management practices may affect the wind resource through alterations of land-surface properties. We use the weather research and forecasting (WRF) model to estimate the impact of crop height variations on the wind resource in the presence of a large turbine array. A hypothetical wind farm consisting of 121 1.8-MW turbines is represented using the WRF model wind-farm parametrization. We represent the impact of selecting soybeans rather than maize by altering the aerodynamic roughness length inmore » a region approximately 65 times larger than that occupied by the turbine array. Roughness lengths of 0.1 and 0.25 m represent the mature soy crop and a mature maize crop, respectively. In all but the most stable atmospheric conditions, statistically significant hub-height wind-speed increases and rotor-layer wind-shear reductions result from switching from maize to soybeans. Based on simulations for the entire month of August 2013, wind-farm energy output increases by 14 %, which would yield a significant monetary gain. Further investigation is required to determine the optimal size, shape, and crop height of the roughness modification to maximize the economic benefit and minimize the cost of such crop-management practices. As a result, these considerations must be balanced by other influences on crop choice such as soil requirements and commodity prices.« less

  9. Vertical distribution of heavy metals in soil profile in a seasonally waterlogging agriculture field in Eastern Ganges Basin.

    PubMed

    Rajmohan, N; Prathapar, S A; Jayaprakash, M; Nagarajan, R

    2014-09-01

    The accumulation of heavy metals in soil and water is a serious concern due to their persistence and toxicity. This study investigated the vertical distribution of heavy metals, possible sources and their relation with soil texture in a soil profile from seasonally waterlogged agriculture fields of Eastern Ganges basin. Fifteen samples were collected at ~0.90-m interval during drilling of 13.11 mbgl and analysed for physical parameters (moisture content and grain size parameters: sand, silt, clay ratio) and heavy metals (Fe, Mn, Cr, Cu, Pb, Zn, Co, Ni and Cd). The average metal content was in the decreasing order of Fe > Mn > Cr > Zn > Ni > Cu > Co > Pb > Cd. Vertical distribution of Fe, Mn, Zn and Ni shows more or less similar trends, and clay zone records high concentration of heavy metals. The enrichment of heavy metals in clay zone with alkaline pH strongly implies that the heavy metal distributions in the study site are effectively regulated by soil texture and reductive dissolution of Fe and Mn oxy-hydroxides. Correlation coefficient analysis indicates that most of the metals correlate with Fe, Mn and soil texture (clay and silt). Soil quality assessment was carried out using geoaccumulation index (I(geo)), enrichment factor (EF) and contamination factor (CF). The enrichment factor values were ranged between 0.66 (Mn) and 2.34 (Co) for the studied metals, and the contamination factor values varied between 0.79 (Mn) and 2.55 (Co). Results suggest that the elements such as Cu and Co are categorized as moderate to moderately severe contamination, which are further confirmed by I(geo) values (0.69 for Cu and 0.78 for Co). The concentration of Ni exceeded the effects-range median values, and the biological adverse effect of this metal is 87%. The average concentration of heavy metals was compared with published data such as concentration of heavy metals in Ganga River sediments, Ganga Delta sediments and upper continental crust (UCC

  10. SIGNAL : Water vapour flux variability and local wind field investigations within five differently managed agroforestry sites across Germany

    NASA Astrophysics Data System (ADS)

    Markwitz, Christian; Siebicke, Lukas; Knohl, Alexander

    2016-04-01

    Optimising soil water uptake and ground water consumption in mono-specific agricultural systems plays an important role for sustainable land management. By including tree alleys into the agricultural landscape, called agroforestry (AF), the wind flow is modified leading to a presumably favourable microclimate behind the tree alleys. We expect that this zone is characterized by increased air temperature and atmospheric water vapour content, compared to mono-specific fields. This would extend the growing season and increase the yield production behind the tree alleys. Within the SIGNAL (Sustainable Intensification of Agriculture through Agroforestry) project the evapotranspiration (ET) variability and the local wind field of agroforestry sites compared to mono-specific agricultural systems is investigated. Our study is based on the comparison of five differently managed agroforestry sites across Germany. All site feature one agroforestry plot and one reference plot, which represents a mono-specific cropped system. Each plot is equipped with an eddy-covariance tower, including a high frequency 3D SONIC anemometer and instruments gathering standard meteorological parameter as pressure, temperature, relative humidity, precipitation, ground heat flux, net- and global radiation. The Surface Energy Budget (SEB) method will be used to calculate evapotranspiration QE as QE = ‑ QN ‑ QH ‑ QG ‑ Res by measuring the sensible heat flux, QH, with the eddy covariance method, the radiation balance, QN and the ground heat flux, QG. QH and QN will be measured continuously long-term. We will quantify site specific energy balance non-closure, Res, by temporarily measuring QE, using eddy covariance and a roving tower and then solving the SEB equation for Res. The short term Res will be used to then continuously derive QE from the SEB method. We will compare measured evapotranspiration rates from the SEB method to modelled evapotranspiration of the agroforestry systems through

  11. Toward linking maize chemistry to archaeological agricultural sites in the North American Southwest

    USGS Publications Warehouse

    Cordell, L.S.; Durand, S.R.; Antweiler, R.C.; Taylor, H.E.

    2001-01-01

    Maize (Zea mays L.) was the staple domestic food crop for Ancestral Pueblo people throughout the northern American Southwest. It is thought to have been the basic food of the inhabitants of Chaco Canyon. New Mexico, a location that was a major centre of Ancestral Pueblo building and population during the 11th and early 12th centuries AD. Modern heirloom varieties of Native American corn have been difficult to grow in experimental fields in Chaco Canyon. Given an abundance of apparent storage structures in Chacoan buildings, it is possible that some corn recovered from archaeological contexts, was imported from surrounding areas. The ultimate goal of this research is to determine whether the corn in Chaco Canyon was grown locally or imported. This paper establishes the feasibility of a method to accomplish this goal. This study reports the results of using inductively coupled plasma-mass spectrometric (ICP-MS) instrumentation to determine chemical constituents of experimental fields and modern heirloom varieties of Native American corn. Analysis of 19 elements is adequate to differentiate soil and corn from three field areas. These results are promising: however, a number of problems, including post-depositional alterations in maize, remain to be solved. ?? 2001 Academic Press.

  12. Stable isotopes in nitrous oxide emitted from tropical rain forest soils and agricultural fields: Implications for the global atmospheric nitrous oxide budget

    NASA Astrophysics Data System (ADS)

    Perez, Tibisay Josefina

    Nitrous oxide (N2O) is an important greenhouse gas and is the primary source of NOx in the stratosphere. Large uncertainties exist in the global N2O budget, mainly due to the high uncertainty associated with source estimates. Recently, stable isotopes of 15N and 18O have been proposed as a tool to better constrain the N2O global budget. This thesis develops analytical methods for constraining and measuring stable isotopes in N2O emitted from soils and reports initial investigations of N2O isotopes from the largest sources in the global N2O budget: tropical rain forest soils and agricultural fields. We found significant differences in the isotopic composition of N 2O emitted from tropical rain forest soils and fertilized agricultural fields. Differences were largest for 15N. Emission-weighted δ 15N-N2O were -26 +/- 2.5‰ s.d., n = 3 (Costa Rican forest), -6.6 +/- 11.3‰ s.d. n = 14 (Brazilian forest) and -36.7 +/- 9.2‰ s.d. n = 19 (Mexican agricultural field and Costa Rican Papaya plantation). We attribute the large range in δ 15N from tropical rain forests, where denitrification is the main source of N2O, to differences in the degree of N2O to N2 reduction. We attribute the very light δ15N values in fertilized agricultural fields to the enhanced nitrogen availability in the soils which facilitates higher fractionation between substrates and products. Similarly, in the Brazilian tropical forest lighter δ 15N-N2O from a local area of enhanced emission is attributed to locally more abundant N- substrate in that particular soil site. If the increase of N2O in the troposphere over the past 100 years is attributable to increased use of N fertilizer, and assuming that light δ 15N- N2O isotopic values are associated with agricultural practices, we expect the δ15N-N2O in the troposphere to have decreased since pre-industrial times. Theoretically, comparison of 15N and 18O signature of emitted N2O with precursors species (NO3 -, NH4+, H2O and O 2) should uniquely

  13. Atrazine soil core residue analysis from an agricultural field 21 years after its ban.

    PubMed

    Vonberg, David; Hofmann, Diana; Vanderborght, Jan; Lelickens, Anna; Köppchen, Stephan; Pütz, Thomas; Burauel, Peter; Vereecken, Harry

    2014-07-01

    Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) groundwater monitoring in the Zwischenscholle aquifer in western Germany revealed concentrations exceeding the threshold value of 0.1 μg L and increasing concentration trends even 20 yr after its ban. Accordingly, the hypothesis was raised that a continued release of bound atrazine residues from the soil into the Zwischenscholle aquifer in combination with the low atrazine degradation in groundwater contributes to elevated atrazine in groundwater. Three soil cores reaching down to the groundwater table were taken from an agricultural field where atrazine had been applied before its ban in 1991. Atrazine residues were extracted from eight soil layers down to 300 cm using accelerated solvent extraction and analyzed using liquid chromatography-tandem mass spectrometry. Extracted atrazine concentrations ranged between 0.2 and 0.01 μg kg for topsoil and subsoil, respectively. The extracted mass from the soil profiles represented 0.07% of the applied mass, with 0.01% remaining in the top layer. A complete and instantaneous remobilization of atrazine residues and vertical mixing with the groundwater body below would lead to atrazine groundwater concentrations of 0.068 μg L. Considering the area where atrazine was applied in the region and assuming instantaneous lateral mixing in the Zwischenscholle aquifer would result in a mean groundwater concentration of 0.002 μg L. A conservative estimation suggests an atrazine half-life value of about 2 yr for the soil zone, which significantly exceeds highest atrazine half-lives found in the literature (433 d for subsurface soils). The long-term environmental behavior of atrazine and its metabolites thus needs to be reconsidered. PMID:25603092

  14. Changes in water budgets and sediment yields from a hypothetical agricultural field as a function of landscape and management characteristics--A unit field modeling approach

    USGS Publications Warehouse

    Roth, Jason L.; Capel, Paul D.

    2012-01-01

    Crop agriculture occupies 13 percent of the conterminous United States. Agricultural management practices, such as crop and tillage types, affect the hydrologic flow paths through the landscape. Some agricultural practices, such as drainage and irrigation, create entirely new hydrologic flow paths upon the landscapes where they are implemented. These hydrologic changes can affect the magnitude and partitioning of water budgets and sediment erosion. Given the wide degree of variability amongst agricultural settings, changes in the magnitudes of hydrologic flow paths and sediment erosion induced by agricultural management practices commonly are difficult to characterize, quantify, and compare using only field observations. The Water Erosion Prediction Project (WEPP) model was used to simulate two landscape characteristics (slope and soil texture) and three agricultural management practices (land cover/crop type, tillage type, and selected agricultural land management practices) to evaluate their effects on the water budgets of and sediment yield from agricultural lands. An array of sixty-eight 60-year simulations were run, each representing a distinct natural or agricultural scenario with various slopes, soil textures, crop or land cover types, tillage types, and select agricultural management practices on an isolated 16.2-hectare field. Simulations were made to represent two common agricultural climate regimes: arid with sprinkler irrigation and humid. These climate regimes were constructed with actual climate and irrigation data. The results of these simulations demonstrate the magnitudes of potential changes in water budgets and sediment yields from lands as a result of landscape characteristics and agricultural practices adopted on them. These simulations showed that variations in landscape characteristics, such as slope and soil type, had appreciable effects on water budgets and sediment yields. As slopes increased, sediment yields increased in both the arid and

  15. Agricultural Waste.

    PubMed

    Xue, Ling; Zhang, Panpan; Shu, Huajie; Chang, Chein-Chi; Wang, Renqing; Zhang, Shuping

    2016-10-01

    In recent years, the quantity of agricultural waste has been rising rapidly all over the world. As a result, the environmental problems and negative impacts of agricultural waste are drawn more and more attention. Therefore, there is a need to adopt proper approaches to reduce and reuse agricultural waste. This review presented about 200 literatures published in 2015 relating to the topic of agricultural waste. The review examined research on agricultural waste in 2015 from the following four aspects: the characterization, reuse, treatment, and management. Researchers highlighted the importance to reuse agricultural waste and investigated the potential to utilize it as biofertilizers, cultivation material, soil amendments, adsorbent, material, energy recycling, enzyme and catalyst etc. The treatment of agricultural waste included carbonization, biodegradation, composting hydrolysis and pyrolysis. Moreover, this review analyzed the differences of the research progress in 2015 from 2014. It may help to reveal the new findings and new trends in this field in 2015 comparing to 2014. PMID:27620093

  16. Fields of dreams: Agriculture, economy and nature in Midwest United States biofuel production

    NASA Astrophysics Data System (ADS)

    Gillon, Sean Thomas

    This work explores the social and ecological dimensions of recent biofuel production increases in the United States (US), focusing on the case of Iowa. Biofuels are proposed to mitigate the greenhouse gas emissions that cause climate change, improve US energy security, and support rural economies. Little research has examined how increased US Midwestern biofuels production will change social and ecological outcomes at farm and regional levels or interact with broader governance processes at the nexus of agriculture, energy and environment. These broad questions guide my research: (1) How does biofuel production reconfigure agricultural practice and landscapes in Iowa? (2) What are the costs, benefits and risks of increased biofuels production as seen by farmers and rural residents, and how do these factors influence farmer decisions about agriculture and conservation practice? (3) How and with what effects are biofuels initiatives constituted as a form of environmental governance through scientific knowledge and practice and political economic dynamics? To address these questions, this research integrates both qualitative and quantitative methods, drawing on a political ecological approach complemented by agroecological analysis and theoretical insights from geographical analyses of nature-society relations. Quantitative analysis focuses on changing land use patterns in agriculture and conservation practice in Iowa. Qualitative methods include extensive interviews, participant observation, and policy and document analyses. Fieldwork focused on Northeastern Iowa to understand regional changes in agricultural and conservation practice, the renegotiated position of farmers in agriculture and biofuel production, and biofuel industry development. I find that biofuel production presents significant social and ecological challenges for rural places of production. Longstanding, unequal political economic relations in industrialized agriculture limit rural economic benefits

  17. Nitrous oxide emissions from European agriculture; an analysis of variability and drivers of emissions from field experiments

    NASA Astrophysics Data System (ADS)

    Rees, R. M.; Augustin, J.; Alberti, G.; Ball, B. C.; Boeckx, P.; Cantarel, A.; Castaldi, S.; Chirinda, N.; Chojnicki, B.; Giebels, M.; Gordon, H.; Grosz, B.; Horvath, L.; Juszczak, R.; Klemedtsson, Å. K.; Klemedtsson, L.; Medinets, S.; Machon, A.; Mapanda, F.; Nyamangara, J.; Olesen, J.; Reay, D.; Sanchez, L.; Sanz Cobena, A.; Smith, K. A.; Sowerby, A.; Sommer, M.; Soussana, J. F.; Stenberg, M.; Topp, C. F. E.; van Cleemput, O.; Vallejo, A.; Watson, C. A.; Wuta, M.

    2012-07-01

    Nitrous oxide emissions from a network of agricultural experiments in Europe and Zimbabwe were used to explore the relative importance of site and management controls of emissions. At each site, a selection of management interventions were compared within replicated experimental designs in plot based experiments. Arable experiments were conducted at Beano in Italy, El Encin in Spain, Foulum in Denmark, Logården in Sweden, Maulde in Belgium, Paulinenaue in Germany, Harare in Zimbabwe and Tulloch in the UK. Grassland experiments were conducted at Crichton, Nafferton and Peaknaze in the UK, Gödöllö in Hungary, Rzecin in Poland, Zarnekow in Germany and Theix in France. Nitrous oxide emissions were measured at each site over a period of at least two years using static chambers. Emissions varied widely between sites and as a result of manipulation treatments. Average site emissions (throughout the study period) varied between 0.04 and 21.21 kg N2O-N ha-1 yr-1, with the largest fluxes and variability associated with the grassland sites. Total nitrogen addition was found to be the single most important determinant of emissions, accounting for 15% of the variance (using linear regression) in the data from the arable sites (p < 0.0001), and 77% in the grassland sites. The annual emissions from arable sites were significantly greater than those that would be predicted by IPCC default emission factors. Variability in N2O within sites that occurred as a result of manipulation treatments was greater than that resulting from site to site and year to year variation, highlighting the importance of management interventions in contributing to greenhouse gas mitigation.

  18. Nonpotential magnetic fields at sites of gamma-ray flares

    NASA Technical Reports Server (NTRS)

    Hagyard, M. J.; Venkatakrishnan, P.; Smith, J. B., Jr.

    1990-01-01

    The relation between the degree of nonpotentiality of photospheric magnetic fields and the occurrence of gama-ray flares is examined to determine whether there are special signatures of the stressed fields for this type of flare. Observations of the flares in the active region of April 1984 (AR 4474) are analyzed, showing that the big flare initiated at the location on the magnetic neutral line where the field deviated the most from a potential field. The nonpotential signatures of AR 4474 are compared with those of four other regions. The results suggest that gamma-ray flares are associated with strongly nonpotential fields that extend over relatively larger lengths of the magnetic neutral line that the fields associated with flares that do not produce gamma-ray events.

  19. Zoning of an agricultural field using a fuzzy indicator model in combination with tool for multi-attributed decision-making

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zoning of agricultural fields is an important task for utilization of precision farming technology. This paper extends previously published work entitled “Zoning of an agricultural field using a fuzzy indicator model” to a general case where there is disagreement between groups of managers or expert...

  20. Using GPR early-time amplitude analysis to monitor variations in soil water content at a clay-rich agricultural site in response to irrigation

    NASA Astrophysics Data System (ADS)

    Algeo, Jonathan; Van Dam, Remke; Slater, Lee

    2015-04-01

    Geophysical methods are increasingly used to analyze spatial variation in soil water content (SWC). Electrical resistivity (ER), ground-penetrating radar (GPR), and time-domain reflectometry (TDR) have all been applied to this problem. However, TDR is limited in terms of its ability to provide good spatial coverage over large areas, ER can be very time consuming depending on the survey, and GPR direct wave and reflection methods are ineffective in clay-rich environments. We employed a relatively new GPR methodology, early-time amplitude analysis, during an infiltration experiment conducted in a clay-rich agricultural field. The research took place at the Samford Ecological Research Facility, Queensland, Australia, with the goal of monitoring changes in SWC in response to irrigation. We hypothesize that early-time analysis can be used to detect and monitor infiltration in clay-rich soils where direct wave and reflection GPR fails, thus opening new avenues of hydrogeophysical research in the increasingly important field of water resource management. Initial field work showed that traditional methods of using GPR reflection surveys and ground wave velocity analysis were ineffective due to the excessive signal attenuation caused by the clay-rich soil at the site. GPR and TDR datasets were collected over a 20 meter by 15 meter section of the field. GPR datasets were collected once daily, at 10 am, and TDR measurements were collected once daily at 11 am from Thursday, August 28th, 2014 until Monday, September 1st, 2014. A sprinkler irrigation was carried out on the evening of Thursday, August 28th. The results suggest that the early-time GPR method is capable of monitoring the resulting changes in SWC due to infiltration in clayey soils despite the failure of reflection and ground wave velocity analysis. The early time GPR results are consistent with moisture content estimates from TDR and gravimetric analysis of soil cores taken in the field.

  1. Field evaluation of hazardous waste site bioassessment protocols

    SciTech Connect

    Thomas, J.M.; Cline, J.F.; Cushing, C.E.; McShane, M.C.; Rogers, J.E.; Rogers, L.E.; Simpson, J.C.; Skalski, J.R.

    1983-04-01

    The goals were: (1) determine the variability (both within and between laboratories) for the various bioassay procedures using contaminated soil samples from the Rocky Mountain Arsenal (RMA); (2) assess variability within and between plots for several assessment techniques (for sampling small mammals, plants, insects including honeybees and microarthropods) so that field studies could be designed to detect a defined biotic change; (3) establish three field plant transects which are apparently (a) contaminated, (b) appear contaminated and (c) could serve as a control; (4) assess the feasibility (in the laboratory) of using Basin F water to contaminate RMA soil artificially, and to supply information for the design of a field plot study in 1983; (5) attempt to obtain preliminary data on any promising field or laboratory bioassessment techniques not currently mentioned in the statement of work; and (6) obtain field data to assess the ecological status of RMA lakes and compare these observations to results from bioassessment testing.

  2. Iron coated sand/glauconite filters for phosphorus removal from artificially drained agricultural fields

    NASA Astrophysics Data System (ADS)

    Vandermoere, Stany; De Neve, Stefaan

    2016-04-01

    Flanders (Belgium) is confronted with reactive phosphorus concentrations in streams and lakes which are three to four times higher than the 0.1 ppm P limit set by the Water Framework Directive. Much of the excessive P input in surface waters is derived from agriculture. Direct P input from artificially drained fields (short-circuiting the buffering capacity of the subsoil) is suspected to be one of the major sources. We aim to develop simple and cheap filters that can be directly installed in the field to reduce P concentration from the drain water. Here we report on the performance of such filters tested at lab scale. As starting materials for the P filter, iron coated sand and acid pre-treated glauconite were used. These materials, both rich in Fe, were mixed in ratios of 75/25, 65/35, 50/50 and 0/100 (iron coated sand/glauconite ratio based on weight basis) and filled in plastic tubes. A screening experiment using the constant head method with a 0.01 M CaCl2 solution containing 1 ppm P showed that all four types of mixtures reduced the P concentration in the outflowing water to almost zero, and that the 75/25, 65/35 and 0/100 mixtures had a sufficiently large hydraulic conductivity of 0.9 to 6.0 cm/min, while the hydraulic conductivity of the 50/50 mixture was too low (< 0.4 cm/min). In a second experiment the iron coated sand and acid pre-treated glauconite were mixed in ratios of 75/25, 65/35 and 0/100 and filled in the same plastic tubes as in the first experiment. Subsequently a 0.01 M CaCl2 solution containing 1 ppm P was passed through the filters over several days, in amounts equivalent to half of the yearly water volume passing through the drains. This experiment firstly showed that in all cases the hydraulic conductivity fluctuated strongly: it decreased from 4.0-6.0 cm/min to 2.0-1.5 cm/min for the 75/25 filter, and to values < 0.4 cm/min for the 65/35 filter, whereas it increased from 0.8 to 1.4 cm/min for the 0/100 filter. Secondly, we observed a

  3. Accidental Strangulation Due to Entrapment of Saree in Crop Thrasher Machine in an Elderly Women Working at Agricultural Field.

    PubMed

    Parchake, Manoj Bhausaheb; Kumre, Vikas; Kachare, Rajesh V

    2016-09-01

    Strangulation is generally considered as homicidal death and in accidental strangulation circumstantial evidence alone can point toward the accidental nature of incidence. In present case, a 71-year-old woman, wearing a saree (garment worn by traditional women in India) working in agricultural field, got entangled in the crop thrasher machine and got strangled. Immediately, she was taken to the nearest hospital, where she survived for 6 to 8 hours and then died. The autopsy reveals cross ribbon-shaped ligature mark on neck and anterior chest along with 1 puncture wound at the right lateral aspect of the neck. A lack of proper precaution and safety measures at agricultural field are other contributing factors. Accidental strangulation by saree is extremely rare, hence, this case is presented for its rarity and pattern of injury. PMID:27311083

  4. Land reclamation on the Nevada Test Site: A field tour

    SciTech Connect

    Winkel, V.K.; Ostler, W.K.

    1993-12-31

    An all-day tour to observe and land reclamation on the Nevada Test Site was conducted in conjunction with the 8th Wildland Shrub and Arid Land Restoration Symposium. Tour participants were introduced to the US Department of Energy reclamation programs for Yucca Mountain Site Characterization Project and Treatability Studies for Soil Media (TSSM) Project. The tour consisted of several stops that covered a variety of topics and studies including revegetation by seeding, topsoil stockpile stabilization, erosion control, shrub transplanting, shrub herbivory, irrigation, mulching, water harvesting, and weather monitoring.

  5. Multi-frequency SAR data for soil surface moisture estimation over agricultural fields

    NASA Astrophysics Data System (ADS)

    Zribi, Mehrez; Baghdadi, Nicolas

    2015-04-01

    Soil moisture plays a crucial role in the continental water cycle, in particular through its influence on the distribution of precipitation between surface runoff and infiltration, which is the main driver behind most hydrological and geomorphologic processes. Although there is now a good understanding of soil hydrodynamics and water transfer in porous media, the development of reliable techniques allowing field heterogeneities to be fully analyzed in space and time remains a key issue. In recent decades, various inversion models have been proposed for the retrieval of surface parameters (mainly soil moisture and surface roughness) from Synthetic Aperture Radar (SAR) high resolution measurements. The proposed techniques depend particularly on two instrumental parameters: the radar system's spatial resolution and the number of configurations measured during satellite acquisitions (mainly incidence angle and polarization). In this paper, our objective is to illustrate different applications of SAR data to estimate soil moisture over bare soil and vegetation cover areas (wheat, olive groves, meadows ...). Potential of very high resolution data, with the availability of TerraSAR-X and COSMO-SkyMed constellations is also discussed. This study is based on different experimental campaigns organized over different sites in humid and semi-arid regions. Ground measurements (soil moisture, soil roughness, vegetation description) over test fields were carried out simultaneously to SAR measurements. Effect of vegetation attenuation on radar signal is considered through a synergy with optical remote sensing. Soil moisture precision for all proposed applications is generally ranged between 3 and 5% of volumetric moisture. These methodologies are developed in the context of the preparation for having a high soil moisture operational product, with SENTINEL and/or the other planned constellations. After an analysis of radar data sensitivity (C and X bands) to surface parameters

  6. The fate and transport of the Cry1Ab protein in an agricultural field and laboratory aquatic microcosms.

    PubMed

    Strain, Katherine E; Lydy, Michael J

    2015-08-01

    Genetically engineered crops expressing insecticidal crystalline proteins derived from Bacillus thuringiensis (Bt), were commercialized almost two decades ago as a means to manage agricultural pests. The Bt proteins are highly specific and only lethal upon ingestion, limiting the scope of toxicity to target insects. However, concern of exposure to non-target organisms and negative public perceptions regarding Bt crops has caused controversy surrounding their use. The objective of this research was to monitor the fate and transport of a Bt protein, Cry1Ab, in a large-scale agricultural field containing maize expressing the Cry1Ab protein and a non-Bt near isoline, and in aquatic microcosms. The highest environmental concentrations of the Cry1Ab protein were found in runoff water and sediment, up to 130ngL(-1) and 143ngg(-1) dry weight, respectively, with the Cry1Ab protein detected in both Bt and non-Bt maize fields. As surface runoff and residual crop debris can transport Bt proteins to waterways adjacent to agricultural fields, a series of laboratory experiments were conducted to determine the potential fate of the Cry1Ab protein under different conditions. The results showed that sediment type and temperature can influence the degradation of the Cry1Ab protein in an aquatic system and that the Cry1Ab protein can persist for up to two months. Although Cry1Ab protein concentrations measured in the field soil indicate little exposure to terrestrial organisms, the consistent input of Bt-contaminated runoff and crop debris into agricultural waterways is relevant to understanding potential consequences to aquatic species. PMID:25828252

  7. Metal contamination of soil and translocation in vegetables growing under industrial wastewater irrigated agricultural field of Vadodara, Gujarat, India.

    PubMed

    Tiwari, K K; Singh, N K; Patel, M P; Tiwari, M R; Rai, U N

    2011-09-01

    The present investigation was carried out to evaluate metals concentration in ten vegetable crops growing in mixed industrial effluent irrigated agricultural field near Vadodara, Gujarat, India. Differential accumulation and translocation of various metals in selected vegetables plant species was observed. A higher concentration of metals were found in order of Fe>Mn>Zn>Cd>Cu>Pb>Cr>As in soil irrigated with industrial effluent than soil irrigated with tube well water; however, the concentration of As, Cr and Pb found below detection limit in tube well water irrigated soil. Metal accumulation in root and top of vegetables varied significantly both in relations to metal concentration in the soil and the plant genotype. Among ten vegetable species studied five vegetable species, i.e. Spinach, Radish, Tomato, Chili and Cabbage growing in mixed industrial effluent irrigated agricultural field showed high accumulation and translocation of toxic metals (As, Cd, Cr, Pb and Ni) in their edible parts, thus, their cultivation are unsafe with respect to possible transfer in food chain and health hazards. However, it is suggested that vegetable crops restricting toxic metal in non-edible port may be recommended for cultivation in such metal contaminated agricultural field. PMID:21555153

  8. Field evaluation of hazardous waste site bioassessment protocols. Volume 2

    SciTech Connect

    Thomas, J.M.; Cline, J.F.; Gano, K.A.; McShane, M.C.; Rogers, J.E.; Rogers, L.E.; Simpson, J.C.; Skalski, J.R.

    1984-04-01

    The overall goal of the plan was to demonstrate that honeybees could be used in detecting likely areas of chemical pollution, to demonstrate the usefulness of microbial and plant phytoassays, and to demonstrate a relationship between laboratory derived phytotoxicity results and field observations of plant community structure and diversity. Field studies were conducted through a cooperative arrangement with the US Army arsenal in Commerce City, Colorado.

  9. Dissipation and effects of chlortetracycline and tylosin in two agricultural soils: a field-scale study in southern Denmark.

    PubMed

    Halling-Sørensen, Bent; Jacobsen, Anne-Marie; Jensen, John; Sengeløv, Gitte; Vaclavik, Elvira; Ingerslev, Flemming

    2005-04-01

    Presently, there is a basic lack of information concerning the accumulation of antibacterial agent residues in agricultural soils. In this field study, performed in southern Denmark, we assess the dissipation of chlortetracycline (CTC), and tylosin A (TYL A) as a function of time. Field soils were classified as a sandy loam soil (field A) and a sandy soil (field B) and each field was sampled on six occasions during the 155-d experimental period from May to October 2000 for chemical analysis and counts of colony-forming units (CFU) detecting the level of aerobic bacteria surviving antibiotic exposure. Colony-forming units and TYL A were detected throughout the entire sampling period, with respective starting soil concentrations of 30 and 50 microg kg(-1) soil declining to 1 and 5 microg kg(-1) soil, on day 155. Compound half-lives (95% confidence limits in parentheses) were estimated for both fields and T1/2 for CTC was 25 d (20-34) and 34 d (28-42) in fields A and B, respectively, and T1/2 for TYL A was 67 d (54-86) and 49 d (40-64) in fields A and B, respectively. No significant difference was determined between compound half-lives on the two fields. The level of aerobic antibiotic-resistant bacteria in the soil over time and soil fauna community was assessed in relation to application of manure containing antibacterial agents to the agricultural fields. The level of both CTC- and TYL-resistant bacteria was affected in the soil by amendment of manure, but declined during the study to the same level as observed at the beginning. PMID:15839553

  10. Incorporating Sustainability into Site Closure - A Field Example

    NASA Astrophysics Data System (ADS)

    Austrins, L. M.; West, J.

    2013-12-01

    Long term management of former chemical production facilities can be a costly and time consuming element of site closure, however, implementation of creative measures to introduce sustainability and reduce the need for onsite presence can be successfully incorporated into the site closure process. A case study demonstrating this involves a facility located in Sarnia, Ontario, which was an active multi chemical production facility from the 1940s, until it was decommissioned and sold between 2005 and 2010. The facility consisted of 322 acres of production areas. Several elements which allowed for reduced onsite presence and lower management costs were incorporated into the site decommissioning plan, including; phased remediation planning, and selection of sustainable components as part of remediation, surface water management, and groundwater management. The sustainability and management modifications were successfully negotiated and approved by the local regulatory agency. Due to the size and complexity of the site, a holistic approach for the facility was needed and included the development of a comprehensive decision matrix. Each remediation alternative incorporated sustainable practices. Ex-situ remediation consisted of excavation of contaminated subsurface medium and consolidation at a 4.7 acre onsite soil treatment area designed specifically for the site closure process. In-situ remediation consisted of injection of amendment into the native soils using hydraulic fracture and injection. When the plant was an active operating facility, groundwater management required active pumping and groundwater treatment through a series of carbon treatment units. Active pumping has been replaced by passive hydraulic control through the use of tree plantations.

  11. Utilizing In-Situ Static Chamber Measurements and UAV Imagery for Integrated Greenhouse Gas Emissions Estimations: Assessing Environmental and Management Impacts on Agricultural Emissions for Two Paired-Watershed Sites in Vermont

    NASA Astrophysics Data System (ADS)

    Barbieri, L.; Peterson, F. S.; Wyngaard, J.

    2015-12-01

    Agricultural greenhouse gas (GHG) emissions contribute to ~10-12% of global anthropogenic emissions. While agriculture is a major source of GHG emissions, there is also great potential for mitigation, as emissions can be reduced by utilizing specific field management and fertilization strategies. This study closely monitors hay and corn fields in Vermont in two paired-watershed sites. Carbon dioxide, nitrous oxide and methane emissions were measured weekly using static chambers and a Photoacoustic Gas Sensor (PAS) across both field management treatments: conventional and mitigation. Accurately quantifying emissions from agricultural landscapes is crucial to develop and implement optimal mitigation strategies, but quantifying landscape-wide emissions is challenging. In this study, we show that both field management treatments and environmental conditions (such as field flooding from rain events) significantly affect GHG emissions, and both can be highly spatially variable even on the field-scale. Monitoring this kind of complexity across a watershed is difficult, as most current emissions quantification techniques, such as static chambers, are localized, point specific and costly. Remote sensing provides an opportunity to monitor landscapes more efficiently and cost effectively. High resolution imagery from an Unmanned Aerial Vehicle (UAV) can also provide opportunities for more accurate watershed-wide estimates of GHG emission rates based on observable agricultural field conditions and management signals, such as field flooding, fertilizer application method, and cover cropping. Satellite imagery, and even the higher resolution aerial imagery used for agricultural monitoring, do not provide the spatial or temporal resolution needed to monitor the on-field complexities that affect GHG emissions. This study combines and compares environmental and management observations from UAV imagery and in-situ field GHG emissions measurements to determine the effectiveness of

  12. Temporal variability of atmospheric particulate matter and chemical composition during a growing season at an agricultural site in northeastern China.

    PubMed

    Chen, Weiwei; Tong, Daniel; Zhang, Shichun; Dan, Mo; Zhang, Xuelei; Zhao, Hongmei

    2015-12-01

    This study presents the observations of PM10 and PM2.5 concentrations at an agricultural site from April to October 2012 in Dehui city, China. Ambient air was sampled by filter-based samplers and online PM monitors. The filter samples were analyzed to determine the abundance of ionic/inorganic elements, organic carbon (OC) and elemental carbon (EC). The daily PM10 concentrations varied significantly over the monitoring period, with an average of 168±63 (in the range of 52-277)μg/m(3) during the land preparation/planting period (26 April-15 June), 85±65 (36-228)μg/m(3) during the growing season (16 June-25 September), and 207±88 (103-310)μg/m(3) during the harvest period (26 September-31 October). PM2.5 accounted for 44%, 56% and 66% of atmospheric PM10 during these periods, respectively. The PM10 diurnal variation showed a distinct peak from 16:00 to 21:00 (LST) during the growing and harvesting seasons, while a gradual increase throughout the daytime until 17:00 was observed during tilling season. Mineral dust elements (Al, Ca, Fe, and Mg) dominated the PM10 chemical composition during the tilling season; OC, NO3(-), SO4(2-) and NH4(+) during the growing season; and carbonaceous species (i.e., OC and EC) during the harvesting season. Our results indicate that the soil particles emitted by farm tillage and organic matter released from straw burning are the two most significant sources of PM10 emissions contributing to the recurring high pollution events in this region. Therefore, development of agricultural PM inventories from soil tillage and straw burning is prioritized to support air quality modeling. PMID:26702977

  13. Determination of atmospheric nitrogen deposition to a semi-natural peat bog site in an intensively managed agricultural landscape

    NASA Astrophysics Data System (ADS)

    Hurkuck, Miriam; Brümmer, Christian; Mohr, Karsten; Grünhage, Ludger; Flessa, Heinz; Kutsch, Werner L.

    2014-11-01

    Rising levels of atmospheric nitrogen (N) deposition have been found to affect the primary productivity and species composition of most terrestrial ecosystems. Highly vulnerable ecosystems such as nutrient-poor bogs are expected to respond to increasing N input rates with a decrease in plant species diversity. Our study site - a moderately drained raised bog and one of only very few remaining protected peatland areas in Northwestern Germany - is surrounded by highly fertilised agricultural land and intensive livestock production. We quantified the annual deposition of atmospheric N over a period of two years. Dry deposition rates of different N species and their reactants were calculated from day and night-time concentrations measured by a KAPS denuder filter system. Dry N deposition amounted to 10.9 ± 1.0 kg N ha-1 yr-1 (year 1) and 10.5 ± 1.0 kg N ha-1 yr-1 (year 2). More than 80% of total deposited N was attributed to ammonia (NH3). A strong seasonality in NH3 concentrations and depositions could be observed. Day and night-time concentrations and depositions, however, did not differ significantly. Total N deposition including bulk N deposition resulted in about 25 kg N ha-1 yr-1. Our results suggest that the intensive agricultural land management of surrounding areas and strongly emitting animal husbandry lead to N inputs into the protected peatland area that exceed the ecosystem's specific critical load up to fivefold. This gives rise to the assumption that a further shift in plant species composition with a subsequent alteration of the local hydrological regime can be expected.

  14. Anthropogenic and geogenic Cd, Hg, Pb and Se sources of contamination in a brackish aquifer below agricultural fields

    NASA Astrophysics Data System (ADS)

    Mastrocicco, Micòl; Colombani, Nicolò; Di Giuseppe, Dario; Faccini, Barbara; Ferretti, Giacomo; Coltorti, Massimo

    2015-04-01

    Groundwater quality is often threatened by industrial, agricultural and land use practices (anthropogenic input). In deltaic areas is however difficult to distinguish between geogenic and anthropogenic inorganic contaminants pollution, since these phenomena can influence each other and often display a seasonal cycling. The effect of geogenic groundwater ionic strength (>10 g/l) on the mobility of trace elements like Cd, Hg, Pb and Se was studied in combination with the anthropogenic sources of these elements (fertilizers) in a shallow aquifer. The site is located in the Po river plain (Northern Italy) in an agricultural field belonging to a reclaimed deltaic environment, near Codigoro town. It is 6 ha wide and is drained by a subsurface drainage system made of PVC tile drains with a slope of 3‰, which provides gravity drainage towards two ditches that in turn discharge in a main channel. The whole area has been intensively cultivated with cereal rotation since 1960, mainly using synthetic urea as nitrogen fertilizer at an average rate of 180 kg-N/ha/y and pig slurry at an average rate of 60 kg-N/ha/y. The sediments were analyzed for major and trace elements via XRF, while major ions in groundwater were analyzed via IC and trace elements via ICP-MS. Three monitoring wells, with an inner diameter of 2 cm and screened down to 4 m below ground level, were set up in the field and sampled every four month from 2012 to 2014. The use of intensive depth profiles with resolution of 0.5 m in three different locations, gave insights into groundwater and sediment matrix interactions. To characterize the anthropogenic inputs synthetic urea and pig slurry were analyzed for trace elements via ICP-MS. The synthetic urea is a weak source of Cd and Hg (~1 ppb), while Se and Pb are found below detection limits. The pig slurry is a much stronger source of Se (~19 ppb) and Pb (~23 ppb) and a weak source of Cd (~3 ppb) and Hg (~2 ppb). Although, the mass loading rate pig slurry is

  15. Multi-year assessment of soil-vegetation-atmosphere transfer (SVAT) modeling uncertainties over a Mediterranean agricultural site

    NASA Astrophysics Data System (ADS)

    Garrigues, S.; Olioso, A.; Calvet, J.-C.; Lafont, S.; Martin, E.; Chanzy, A.; Marloie, O.; Bertrand, N.; Desfonds, V.; Renard, D.

    2012-04-01

    Vegetation productivity and water balance of Mediterranean regions will be particularly affected by climate and land-use changes. In order to analyze and predict these changes through land surface models, a critical step is to quantify the uncertainties associated with these models (processes, parameters) and their implementation over a long period of time. Besides, uncertainties attached to the data used to force these models (atmospheric forcing, vegetation and soil characteristics, crop management practices...) which are generally available at coarse spatial resolution (>1-10 km) and for a limited number of plant functional types, need to be evaluated. This paper aims at assessing the uncertainties in water (evapotranspiration) and energy fluxes estimated from a Soil Vegetation Atmosphere Transfer (SVAT) model over a Mediterranean agricultural site. While similar past studies focused on particular crop types and limited period of time, the originality of this paper consists in implementing the SVAT model and assessing its uncertainties over a long period of time (10 years), encompassing several cycles of distinct crops (wheat, sorghum, sunflower, peas). The impacts on the SVAT simulations of the following sources of uncertainties are characterized: - Uncertainties in atmospheric forcing are assessed comparing simulations forced with local meteorological measurements and simulations forced with re-analysis atmospheric dataset (SAFRAN database). - Uncertainties in key surface characteristics (soil, vegetation, crop management practises) are tested comparing simulations feeded with standard values from global database (e.g. ECOCLIMAP) and simulations based on in situ or site-calibrated values. - Uncertainties dues to the implementation of the SVAT model over a long period of time are analyzed with regards to crop rotation. The SVAT model being analyzed in this paper is ISBA in its a-gs version which simulates the photosynthesis and its coupling with the stomata

  16. Meteorological field measurements at potential and actual wind turbine sites

    SciTech Connect

    Renne, D.S.; Sandusky, W.F.; Hadley, D.L.

    1982-09-01

    An overview of experiences gained in a meteorological measurement program conducted at a number of locations around the United States for the purpose of site evaluation for wind energy utilization is provided. The evolution of the measurement program from its inception in 1976 to the present day is discussed. Some of the major accomplishments and areas for improvement are outlined. Some conclusions on research using data from this program are presented.

  17. Integrated description of agricultural field experiments and production: the ICASA version 2.0 data standards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural research increasingly seeks to quantify complex interactions of processes for a wide range of environmental conditions and crop management scenarios, leading to investigation where multiple sets of experimental data are examined using tools such as simulation and regression. The use of ...

  18. Using lidar to characterize particles from point and diffuse sources in an agricultural field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lidar (LIght Detection And Ranging) provides the means to quantitatively evaluate the spatial and temporal variability of particulate emissions from agricultural activities. Aglite is a three-wavelength portable scanning lidar system built at the Energy Dynamics Laboratory (EDL) to measure the spati...

  19. Validating a high-resolution digital soil map for precision agriculture across multiple fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Digital soil mapping (DSM) for precision agriculture (PA) management is aimed at developing models that predict soil properties or classes using legacy soil data, sensors, and environmental covariates. The utility of DSM for PA is based on its ability to provide useful spatial soil information for o...

  20. Evidence for atmospheric deposition of herbicides to forests bordering agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability of a forested system to intercept herbicides from the air, deliver them directly by rainfall to the forest floor and then to a receiving stream within the forested area was evaluated over a four year period in an agricultural watershed in Maryland. The collected rain included through-fa...

  1. Microsatellite analysis of bumble bee foraging in mass flowering agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bumble bees, social insects that provide pollination services in native and agricultural habitats, have declined, in part, due to habitat fragmentation. They require food resources within foraging distances of the nest for colony survival and growth. Foraging distances of workers have been assumed t...

  2. Use of Field-based Near Infrared Sensors to Map Soil Carbon in Agricultural Ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ability to detect changes in soil carbon storage is an important component of verifying sequestration of soil carbon within agricultural ecosystems. Rapid methods of measuring soil carbon such as near infrared spectroscopy have gained considerable interest but problems in accurate measurement still...

  3. Treatment of phosphorus transported from tile and ditch-drained agricultural fields using sorption materials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many flat, poorly drained soils, such as the Delmarva Peninsula, the upper Midwest, and certain areas of Europe such as Denmark and Netherlands, have been extensively drained through the construction of artificial drainage ditches and tiles to allow agriculture and other human activities. In additi...

  4. Barriers to the Adoption of Sustainable Agriculture on Rented Land: An Examination of Contesting Social Fields

    ERIC Educational Resources Information Center

    Carolan, Michael S.

    2005-01-01

    While over half of the cropland in the United States is rented, interest in land tenancy within sociological circles has been sporadic at best. In light of the prevalence of rented land in agriculture--particularly in the Midwest--it is vital that further research be conducted to investigate the effect that the rental relationship has upon the…

  5. THE USE OF CHEMICALS TO CONTROL FIELD RODENTS AND OTHER PREDATORS. AGRICULTURAL CHEMICALS TECHNOLOGY, NUMBER 5.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center for Vocational and Technical Education.

    THE PURPOSE OF THIS GUIDE IS TO ASSIST TEACHERS IN PREPARING POST-SECONDARY STUDENTS FOR AGRICULTURAL CHEMICAL OCCUPATIONS. IT IS ONE OF A SERIES OF MODULES DEVELOPED BY A NATIONAL TASK FORCE ON THE BASIS OF DATA FROM STATE STUDIES. SECTIONS ARE (1) USE OF CHEMICALS FOR RODENT CONTROL AND ERADICATION, (2) TERMINOLOGY AND COMPUTATIONS, (3) RODENT…

  6. Pesticide application to agricultural fields: effects on the reproduction and avoidance behaviour of Folsomia candida and Eisenia andrei.

    PubMed

    Santos, M J G; Ferreira, M F L; Cachada, A; Duarte, A C; Sousa, J P

    2012-11-01

    The objective of this work was to assess the impact of pesticide application to non-target soil organisms simulating what happens following pesticide application in agricultural fields and thus obtaining higher realism on results obtained. For that purpose, three commercial formulations containing the insecticides chlorpyrifos and endosulfan and the herbicide glyphosate were applied to a Mediterranean agricultural field. The soil was collected after spraying and dilution series were prepared with untreated soil to determine the impact of the pesticides on the avoidance behaviour and reproduction of the earthworm Eisenia andrei and the collembolan Folsomia candida. A significant avoidance was observed at the recommended field dose in case of endosulfan by earthworms (60 %) and in case of chlorpyrifos by collembolans (64 %). In addition, both insecticides affected the number of juveniles produced by the earthworms (EC(50) were below the recommended field dose). Glyphosate did not seem to affect either earthworms or collembolans in the recommended field dose. Folsomia candida was more sensitive to pesticide application than Eisenia andrei, what was corroborated by the EC(50) and LC(50) values. In conclusion, insecticides may affect the structure of the soil community by reducing the survival of collembolans and the reproductive capacity of collembolans and earthworms. PMID:22711551

  7. Preliminary assessment of DOC and THM precursor loads from a freshwater restored wetland, an agricultural field, and a tidal wetland in the Sacramento-San Joaquin River Delta

    USGS Publications Warehouse

    Fujii, R.; Bergamaschi, B.A.; Ganju, N.K.; Fleck, J.A.; Burow-Fogg, K.R.; Schoellhamer, D.; Deverel, S.J.

    2003-01-01

    Water exported from the Sacramento-San Joaquin River Delta supplies drinking water to more than 22 million people in California. At certain times of the year, Delta waters contain relatively high concentrations of dissolved organic carbon (DOC) and bromide. During these times, chlorination of Delta water for drinking water disinfection will form disinfection byproducts, such as trihalomethanes (THMs), that can exceed the U.S. Environmental Protection Agency's maximum contaminant level for THMs of 80 mg/L. Important sources of DOC and THM precursors (types of DOC that form THMs when chlorinated) to the Delta include rivers, drainage water from peat islands, water from wetlands and areas with extensive riparian vegetation, and in-channel growth of algae and macrophytes. Due to proposed ecosystem restoration and creation of wetlands in the Delta, there is an urgent need for information on the relative loads of DOC and THM precursors produced from three different land uses: restored wetlands constructed for subsidence mitigation, tidal wetlands, and agricultural operations. We have been conducting research in the Delta to provide this information. A restored wetland and agricultural field located on Twitchell Island, and a tidal wetland on Browns Island have been monitored for flow, DOC, and THM precursors. Initial results indicate that the loads of DOC and THM precursors are similar for the restored wetland (surface water only) and the agricultural field. These land uses produce DOC loads of about 14 and 11 g C/m2/yr, respectively, and THM precursor loads of about 1.7 and 1.0 g THM/m2/yr, respectively. Estimates of DOC and THM precursor loads for the tidal wetland site on Browns Island and seepage associated with the restored wetland are being developed.

  8. Celtic field agriculture and Early Anthropogenic Environmental change in the Meuse-Demer-Scheldt region, NW Europe

    NASA Astrophysics Data System (ADS)

    Van der Sanden, Germaine; Kluiving, Sjoerd; Roymans, Nico

    2016-04-01

    The field of Archaeology remains focused on historical issues while underexploring its potential contribution on currently existing societal problems, e.g. climate change. The aim of this paper is to show the relevance of archeological studies for the research of the 'human species as a significant moving agent' in terms of the changing natural environment during a much earlier time frame. This research is based on the study area of the Meuse-Demer-Scheldt region in the Netherlands and Belgium and exhibits the period from the Late Bronze Age to the Early Roman period. This period is characterized by the widespread introduction and use of an agricultural system, often referred to as the Celtic Field system that served as one of the most modifying systems in terms of anthropogenic-environmental change during this period. Emphasis in this research is given to results generated by the use of the remote sensing technology, LiDAR. New information is reported considering a correlation between singular field size and the overall surface of the agricultural complexes and secondly, the presentation of newly identified Celtic field systems in the Meuse-Demer-Scheldt region are presented. The study of the dynamics of the Celtic Field agricultural system provides evidence for a significant anthropogenic footprint on the natural environment due to land cover dominance, soil degeneration, increased soil acidification and forest clearance. Soil exhaustion forced the inhabitants to re-establish their relationship with the landscape in terms of fundamental changes in the habitation pattern and the agrarian exploitations of the land.

  9. Evaluation in the Field: The Need for Site Visit Standards

    ERIC Educational Resources Information Center

    Patton, Michael Quinn

    2015-01-01

    Our understanding of programs is enhanced when trained, skilled, and observant evaluators go "into the field"--the real world where programs are conducted--paying attention to what's going on, systematically documenting what they see, and reporting what they learn. The article opens by presenting and illustrating twelve reasons for…

  10. Forecasting the Feasibility of Implementing Isolation Perimeters Between GM and non-GM Maize Fields Under Agricultural Conditions

    NASA Astrophysics Data System (ADS)

    Devos, Yann; Cougnon, Mathias; Thas, Olivier; De Clercq, Eva M.; Cordemans, Karl; Reheul, Dirk

    2008-10-01

    Although spatially isolating genetically modified (GM) maize fields from non-GM maize fields is a robust on-farm strategy to keep the adventitious presence of GM material in the harvests of neighboring non-GM maize fields due to cross-fertilizations below established labeling thresholds (and thus to ensure the spatial co-existence between maize cropping systems), the practical implementation of isolation perimeters attracted little research efforts. In this study, the feasibility of implementing isolation perimeters around GM maize fields is investigated. Using Geographic Information System datasets and Monte Carlo simulations, various scenarios differing in shares and spatial distributions of GM maize were tested for various isolation perimeters in six agricultural areas in Flanders. Factors that affect the feasibility of implementing isolation perimeters are discussed.

  11. Evapotranspiration from selected fallowed agricultural fields on the Tule Lake National Wildlife Refuge, California, during May to October 2000

    USGS Publications Warehouse

    Bidlake, W.R.

    2002-01-01

    An investigation of evapotranspiration, vegetation quantity and composition, and depth to the water table below the land surface was made at three sites in two fallowed agricultural lots on the 15,800-hectare Tule Lake National Wildlife Refuge in northern California during the 2000 growing season. All three sites had been farmed during 1999, but were not irrigated since the 1999 growing season. Vegetation at the lot C1B and lot 6 stubble sites included weedy species and small grain plants. The lot 6 cover crop site supported a crop of cereal rye that had been planted during the previous winter. Percentage of coverage by live vegetation ranged from 0 to 43.2 percent at the lot C1B site, from approximately 0 to 63.2 percent at the lot 6 stubble site, and it was estimated to range from 0 to greater than 90 percent at the lot 6 cover crop site. Evapotranspiration was measured using the Bowen ratio energy balance technique and it was estimated using a model that was based on the Priestley-Taylor equation and a model that was based on reference evapotranspiration with grass as the reference crop. Total evapotranspiration during May to October varied little among the three evapotranspiration measurement sites, although the timing of evapotranspiration losses did vary among the sites. Total evapotranspiration from the lot C1B site was 426 millimeters, total evapotranspiration from the lot 6 stubble site was 444 millimeters, and total evapotranspiration from the lot 6 cover crop site was 435 millimeters. The months of May to July accounted for approximately 78 percent of the total evapotranspiration from the lot C1B site, approximately 63 percent of the evapotranspiration from the lot 6 stubble site, and approximately 86 percent of the total evapotranspiration from the lot 6 cover crop site. Estimated growing season precipitation accounted for 16 percent of the growing-season evapotranspiration at the lot C1B site and for 17 percent of the growing-season evapotranspiration

  12. Efficacy of management practices to mitigate the off-site movement and ecological risk of pesticides transported with runoff from agricultural and turf systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly managed biotic systems, such as agricultural crops and managed turf, often require multiple applications of pesticides that may be transported with runoff to areas beyond the intended target site. Pesticides have been detected in surface waters of rural and urban watersheds raising questions ...

  13. Overview of the Bushland Evapotranspiration and Agricultural Remote sensing EXperiment 2008 (BEAREX08): A field experiment evaluating methods for quantifying ET at multiple scales

    NASA Astrophysics Data System (ADS)

    Evett, Steven R.; Kustas, William P.; Gowda, Prasanna H.; Anderson, Martha C.; Prueger, John H.; Howell, Terry A.

    2012-12-01

    In 2008, scientists from seven federal and state institutions worked together to investigate temporal and spatial variations of evapotranspiration (ET) and surface energy balance in a semi-arid irrigated and dryland agricultural region of the Southern High Plains in the Texas Panhandle. This Bushland Evapotranspiration and Agricultural Remote sensing EXperiment 2008 (BEAREX08) involved determination of micrometeorological fluxes (surface energy balance) in four weighing lysimeter fields (each 4.7 ha) containing irrigated and dryland cotton and in nearby bare soil, wheat stubble and rangeland fields using nine eddy covariance stations, three large aperture scintillometers, and three Bowen ratio systems. In coordination with satellite overpasses, flux and remote sensing aircraft flew transects over the surrounding fields and region encompassing an area contributing fluxes from 10 to 30 km upwind of the USDA-ARS lysimeter site. Tethered balloon soundings were conducted over the irrigated fields to investigate the effect of advection on local boundary layer development. Local ET was measured using four large weighing lysimeters, while field scale estimates were made by soil water balance with a network of neutron probe profile water sites and from the stationary flux systems. Aircraft and satellite imagery were obtained at different spatial and temporal resolutions. Plot-scale experiments dealt with row orientation and crop height effects on spatial and temporal patterns of soil surface temperature, soil water content, soil heat flux, evaporation from soil in the interrow, plant transpiration and canopy and soil radiation fluxes. The BEAREX08 field experiment was unique in its assessment of ET fluxes over a broad range in spatial scales; comparing direct and indirect methods at local scales with remote sensing based methods and models using aircraft and satellite imagery at local to regional scales, and comparing mass balance-based ET ground truth with eddy covariance

  14. Product amount and quality monitoring in agricultural fields with remote sensing satellite and radio-control helicopter

    NASA Astrophysics Data System (ADS)

    Arai, Kohei

    Product amount and quality monitoring in agricultural fields with remote sensing satellite and radio-control helicopter is proposed. In particular, tealeaves and rice crop quality and amoujnt monitorings are peoposed as examples. Nitrogen rich tealeaves tasts good. Therefore, quality of tealeaves can be estimated with nitrogen content which is related with near infrared reflectance of the tealeves in concern. Also, rice crop quality depends on protein content in rice grain which is related to near infrared reflectance of rice leaves. Therefore, product quality can be estimated with observation of near infrared reflectance of the leaves in concern. Near infared reflectance is provided by near infrared radiometers onboard remote sensing satellites and by near infrared cameras onboard radio-control helicopter. This monitoring system is applicable to the other agricultural plant products. Through monitoring near ingfrared reflectance, it is possible to estimate quality as well as product amount.

  15. Biological and Agricultural Studies on Application of Discharge Plasma and Electromagnetic Fields 5. Effects of High Electric Fields on Animals

    NASA Astrophysics Data System (ADS)

    Isaka, Katsuo

    The biological effects of extremely low frequency electric fields on animals are reviewed with emphasis on studies of the nervous system, behavior, endocrinology, and blood chemistry. First, this paper provides a histrical overview of studies on the electric field effects initiated in Russia and the United States mainly regarding electric utility workers in high voltage substations and transmission lines. Then, the possible mechanisms of electric field effects are explained using the functions of surface electric fields and induced currents in biological objects. The real mechanisms have not yet been identified. The thresholds of electric field perception levels for rats, baboons, and humans are introduced and compared. The experimental results concerning the depression of melatonin secretion in rats exposed to electric fields are described.

  16. SITE INVESTIGATIONS/FIELD INVESTIGATIONS OF SUPERFUND HAZARDOUS WASTE SITES: APRIL 1, 2003 - MAY 31, 2004

    EPA Science Inventory

    These projects require developing and implementing Work Plans which include the Project Operations Plan, Field Sampling and Analysis Plan, Quality Assurance Plan and the Health and Safety Plan. In general, these large complex investigations involve: collecting soil, sediment, sur...

  17. Nitrate-nitrogen and oxygen isotope ratios for identification of nitrate sources and dominant nitrogen cycle processes in a tile-drained dryland agricultural field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural systems are a leading source of reactive nitrogen to aquatic and atmospheric ecosystems. Natural d15Nnitrate and d18Onitrate are used to identify the dominant nitrogen cycle processes and sources of NO3- leached from a tile-drained, dryland agricultural field. Tile-drain water discharge...

  18. Incorporating dynamic root growth enhances the performance of Noah-MP at two contrasting winter wheat field sites

    NASA Astrophysics Data System (ADS)

    Gayler, Sebastian; Wöhling, Thomas; Ingwersen, Joachim; Wizemann, Hans-Dieter; Warrach-Sagi, Kirsten; Attinger, Sabine; Streck, Thilo; Wulmeyer, Volker

    2014-05-01

    Interactions between the soil, the vegetation, and the atmospheric boundary layer require close attention when predicting water fluxes in the hydrogeosystem, agricultural systems, weather and climate. However, land-surface schemes used in large scale models continue to show deficits in consistently simulating fluxes of water and energy from the subsurface through vegetation layers to the atmosphere. In this study, the multi-physics version of the Noah land-surface model (Noah-MP) was used to identify the processes, which are most crucial for a simultaneous simulation of water and heat fluxes between land-surface and the lower atmosphere. Comprehensive field data sets of latent and sensible heat fluxes, ground heat flux, soil moisture, and leaf area index from two contrasting field sites in South-West Germany are used to assess the accuracy of simulations. It is shown that an adequate representation of vegetation-related processes is the most important control for a consistent simulation of energy and water fluxes in the soil-plant-atmosphere system. In particular, using a newly implemented sub-module to simulate root growth dynamics has enhanced the performance of Noah-MP at both field sites. We conclude that further advances in the representation of leaf area dynamics and root/soil moisture interactions are the most promising starting points for improving the simulation of feedbacks between the sub-soil, land-surface and atmosphere in fully-coupled hydrological and atmospheric models.

  19. Interactively Improving Agricultural Field Mapping in Sub-Saharan Africa with Crowd-Sourcing and Active Learning

    NASA Astrophysics Data System (ADS)

    Debats, S. R.; Estes, L. D.; Caylor, K. K.

    2015-12-01

    As satellite imagery becomes increasingly available, management of large image databases becomes more important for efficient image processing. We have developed a computer vision-based classification algorithm to distinguish smallholder agricultural land cover in Sub-Saharan Africa, using a group of high-resolution images from South Africa as a case study. For supervised classification, smallholder agriculture, with ambiguous patterns of small, irregular fields, requires a wide range of training data samples to adequately describe the variability in appearance. We employ crowd-sourcing to obtain new training data to expand the geographic range of our algorithm. A crowd-sourcing user is asked to hand-digitize the boundaries of agricultural fields in an assigned 1 km2 image. Yet random assignment of images to users could result in a highly redundant training data set with limited discriminative power. Furthermore, larger training data sets require a greater number of users to hand-digitize fields, which increases costs through crowd-sourcing engines like Amazon Mechanical Turk, as well as longer algorithm training times, which increases computing costs. Therefore, we employ an active learning approach to interactively select the most informative images to be hand-digitized for training data by crowd-sourcing users, based on changes in algorithm accuracy. We investigate the use of various image similarity measures used in content-based image retrieval systems, which quantify the distance, such as Euclidean distance or Manhattan distance, between a variety of extracted feature spaces to determine how similar the content of two images are. We determine the minimum training data set needed to maximize algorithm accuracy, as well as automate the selection of additional training images to classify a new target image that expands the geographic range of our algorithm.

  20. Modelling Water Flow, Heat Transport, Soil Freezing and Thawing, and Snow Processes in a Clayey, Subsurface Drained Agricultural Field

    NASA Astrophysics Data System (ADS)

    Warsta, L.; Turunen, M.; Koivusalo, H. J.; Paasonen-Kivekäs, M.; Karvonen, T.; Taskinen, A.

    2012-12-01

    Simulation of hydrological processes for the purposes of agricultural water management and protection in boreal environment requires description of winter time processes, including heat transport, soil freezing and thawing, and snow accumulation and melt. Finland is located north of the latitude of 60 degrees and has one third to one fourth of the total agricultural land area (2.3 milj. ha) on clay soils (> 30% of clay). Most of the clayey fields are subsurface drained to provide efficient drainage and to enable heavy machines to operate on the fields as soon as possible after the spring snowmelt. Generation of drainflow and surface runoff in cultivated fields leads to nutrient and sediment load, which forms the major share of the total load reaching surface waters at the national level. Water, suspended sediment, and soluble nutrients on clayey field surface are conveyed through the soil profile to the subsurface drains via macropore pathways as the clayey soil matrix is almost impermeable. The objective of the study was to develop the missing winter related processes into the FLUSH model, including soil heat transport, snow pack simulation and the effects of soil freezing and thawing on the soil hydraulic conductivity. FLUSH is an open source (MIT license), distributed, process-based model designed to simulate surface runoff and drainflow in clayey, subsurface drained agricultural fields. 2-D overland flow is described with the diffuse wave approximation of the Saint Venant equations and 3-D subsurface flow with a dual-permeability model. Both macropores and soil matrix are simulated with the Richards equation. Soil heat transport is described with a modified 3-D convection-diffusion equation. Runoff and groundwater data was available from different periods from January 1994 to April 1999 measured in a clayey, subsurface drained field section (3.6 ha) in southern Finland. Soil temperature data was collected in two locations (to a depth of 0.8 m) next to the

  1. Spatial variability of soil magnetic susceptibility in an agricultural field located in Eastern Ukraine

    NASA Astrophysics Data System (ADS)

    Menshov, Oleksandr; Pereira, Paulo; Kruglov, Oleksandr

    2015-04-01

    Magnetic susceptibility (MS) have been used to characterize soil properties. It gives an indirect information about heavy metals content and degree of human impacts on soil contamination derived from atmospheric pollution (Girault et al., 2011). This method is inexpensive in relation to chemical analysis and very useful to track soil pollution, since several toxic components deposited on soil surface are rich in particulates produced by oxidation processes (Boyko et al., 2004; Morton-Bernea et al., 2009). Thus, identify the spatial distribution of MS is of major importance, since can give an indirect information of high metals content (Dankoub et al., 2012). This allows also to distinguish the pedogenic and technogenic origin magnetic signal. For example Ukraine chernozems contain fine-grained oxidized magnetite and maghemite of pedogenic origin formed by weathering of the parent material (Jeleńska et al., 2004). However, to a correct understanding of variables distribution, the identification of the most accurate interpolation method is fundamental for a better interpretation of map information (Pereira et al., 2013). The objective of this work is to study the spatial variability of soil MS in an agricultural fields located in the Tcherkascy Tishki area (50.11°N, 36.43 °E, 162 m a.s.l), Ukraine. Soil MS was measured in 77 sampling points in a north facing slope. To estimate the best interpolation method, several interpolation methods were tested, as inverse distance to a weight (IDW) with the power of 1,2,3,4 and 5, Local Polynomial (LP) with the power of 1 and 2, Global Polynomial (GP), radial basis functions - spline with tension (SPT), completely regularized spline (CRS), multiquatratic (MTQ), inverse multiquatratic (IMTQ), and thin plate spline (TPS) - and some geostatistical methods as, ordinary kriging (OK), Simple Kriging (SK) and Universal Kriging (UK), used in previous works (Pereira et al., 2014). On average, the soil MS of the studied plot had 686

  2. Spatial variability of soil magnetic susceptibility in an agricultural field located in Eastern Ukraine

    NASA Astrophysics Data System (ADS)

    Menshov, Oleksandr; Pereira, Paulo; Kruglov, Oleksandr

    2015-04-01

    Magnetic susceptibility (MS) have been used to characterize soil properties. It gives an indirect information about heavy metals content and degree of human impacts on soil contamination derived from atmospheric pollution (Girault et al., 2011). This method is inexpensive in relation to chemical analysis and very useful to track soil pollution, since several toxic components deposited on soil surface are rich in particulates produced by oxidation processes (Boyko et al., 2004; Morton-Bernea et al., 2009). Thus, identify the spatial distribution of MS is of major importance, since can give an indirect information of high metals content (Dankoub et al., 2012). This allows also to distinguish the pedogenic and technogenic origin magnetic signal. For example Ukraine chernozems contain fine-grained oxidized magnetite and maghemite of pedogenic origin formed by weathering of the parent material (Jeleńska et al., 2004). However, to a correct understanding of variables distribution, the identification of the most accurate interpolation method is fundamental for a better interpretation of map information (Pereira et al., 2013). The objective of this work is to study the spatial variability of soil MS in an agricultural fields located in the Tcherkascy Tishki area (50.11°N, 36.43 °E, 162 m a.s.l), Ukraine. Soil MS was measured in 77 sampling points in a north facing slope. To estimate the best interpolation method, several interpolation methods were tested, as inverse distance to a weight (IDW) with the power of 1,2,3,4 and 5, Local Polynomial (LP) with the power of 1 and 2, Global Polynomial (GP), radial basis functions - spline with tension (SPT), completely regularized spline (CRS), multiquatratic (MTQ), inverse multiquatratic (IMTQ), and thin plate spline (TPS) - and some geostatistical methods as, ordinary kriging (OK), Simple Kriging (SK) and Universal Kriging (UK), used in previous works (Pereira et al., 2014). On average, the soil MS of the studied plot had 686

  3. Chemical and biological characterization of products of incomplete combustion from the simulated field burning of agricultural plastic

    SciTech Connect

    Ryan, J.V.; Perry, E.; Linak, W.P.; DeMarini, D.M.; Williams, R.W.

    1989-01-01

    Chemical and biological analyses were performed to characterize products of incomplete combustion emitted during the simulated open-field burning of agricultural plastic. A small utility shed equipped with an air delivery system was used to simulate pile burning and forced-air-curtain incineration of a nonhalogenated agricultural plastic that reportedly consisted of polyethylene and carbon black. Emissions were analyzed for combustion gases; volatile, semi-volatile, and particulate organics; and toxic and mutagenic properties. Emission samples, as well as samples of the used (possibly pesticide-contaminated) plastic, were analyzed for the presence of several pesticides to which the plastic may have been exposed. When mutagenicity was evaluated by exposing Salmonella bacteria (Ames assay) to whole vapor and vapor/particulate emissions, no toxic or mutagenic effects were observed. However, organic extracts of the particulate samples were moderately mutagenic. The study highlights the benefits of a combined chemical/biological approach to the characterization of complex, multi-component combustion emissions. These results may not reflect those of other types of plastic that may be used for agricultural purposes, especially those containing halogens.

  4. Physical and chemical control of released microorganisms at field sites

    SciTech Connect

    Donegan, K.; Seidler, R.; Matyac, C.

    1991-01-01

    An important consideration in the environmental release of a genetically engineered microorganism (GEM) is the capability for reduction or elimination of GEM populations once their function is completed or if adverse environmental effects are observed. The decontamination treatments of burning and biocide application, alone and in combination with tilling, were evaluated for their ability to reduce populations of bacteria released on the phylloplane. Field plots of bush beans sprayed with the bacterium Erwinia herbicola, received the following treatments: (1) control, (2) control + till, (3) burn, (4) burn + till, (5) Kocide (cupric hydroxide), (6) Kocide + till, (7) Agri-strep (streptomycin sulfate), and (8) Agri-strept + till. Leaves and soil from the plots were sampled -1, 1, 5, 8, 12, 15, 19, and 27 days after application of the decontamination treatments. Burning produced a significant and persistent reduction in the number of bacteria whereas tilling, alone or in combination with the biocide treatments, stimulated a significant and persistent reduction in the number of bacteria, whereas tilling, alone or in combination with the biocide treatments, stimulated a significant increase in bacterial populations that persisted for several weeks.

  5. Geological characterization of remote field sites using visible and infrared spectroscopy: Results from the 1999 Marsokhod field test

    USGS Publications Warehouse

    Johnson, J. R.; Ruff, S.W.; Moersch, J.; Roush, T.; Horton, K.; Bishop, J.; Cabrol, N.A.; Cockell, C.; Gazis, P.; Newsom, Horton E.; Stoker, C.

    2001-01-01

    Upcoming Mars Surveyor lander missions will include extensive spectroscopic capabilities designed to improve interpretations of the mineralogy and geology of landing sites on Mars. The 1999 Marsokhod Field Experiment (MFE) was a Mars rover simulation designed in part to investigate the utility of visible/near-infrared and thermal infrared field spectrometers to contribute to the remote geological exploration of a Mars analog field site in the California Mojave Desert. The experiment simultaneously investigated the abilities of an off-site science team to effectively analyze and acquire useful imaging and spectroscopic data and to communicate efficiently with rover engineers and an on-site field team to provide meaningful input to rover operations and traverse planning. Experiences gained during the MFE regarding effective communication between different mission operation teams will be useful to upcoming Mars mission teams. Field spectra acquired during the MFE mission exhibited features interpreted at the time as indicative of carbonates (both dolomitic and calcitic), mafic rocks and associated weathering products, and silicic rocks with desert varnish-like coatings. The visible/near-infrared spectra also suggested the presence of organic compounds, including chlorophyll in one rock. Postmission laboratory petrologic and spectral analyses of returned samples confirmed that all rocks identified as carbonates using field measurements alone were calc-silicates and that chlorophyll associated with endolithic organisms was present in the one rock for which it was predicted. Rocks classified from field spectra as silicics and weathered mafics were recognized in the laboratory as metamorphosed monzonites and diorite schists. This discrepancy was likely due to rock coatings sampled by the field spectrometers compared to fresh rock interiors analyzed petrographically, in addition to somewhat different surfaces analyzed by laboratory thermal spectroscopy compared to field

  6. Geological characterization of remote field sites using visible and infrared spectroscopy: Results from the 1999 Marsokhod field test

    NASA Astrophysics Data System (ADS)

    Johnson, Jeffrey R.; Ruff, Steven W.; Moersch, Jeffrey; Roush, Ted; Horton, Keith; Bishop, Janice; Cabrol, Nathalie A.; Cockell, Charles; Gazis, Paul; Newsom, Horton E.; Stoker, Carol

    2001-04-01

    Upcoming Mars Surveyor lander missions will include extensive spectroscopic capabilities designed to improve interpretations of the mineralogy and geology of landing sites on Mars. The 1999 Marsokhod Field Experiment (MFE) was a Mars rover simulation designed in part to investigate the utility of visible/near-infrared and thermal infrared field spectrometers to contribute to the remote geological exploration of a Mars analog field site in the California Mojave Desert. The experiment simultaneously investigated the abilities of an off-site science team to effectively analyze and acquire useful imaging and spectroscopic data and to communicate efficiently with rover engineers and an on-site field team to provide meaningful input to rover operations and traverse planning. Experiences gained during the MFE regarding effective communication between different mission operation teams will be useful to upcoming Mars mission teams. Field spectra acquired during the MFE mission exhibited features interpreted at the time as indicative of carbonates (both dolomitic and calcitic), mafic rocks and associated weathering products, and silicic rocks with desert varnish-like coatings. The visible/near-infrared spectra also suggested the presence of organic compounds, including chlorophyll in one rock. Postmission laboratory petrologic and spectral analyses of returned samples confirmed that all rocks identified as carbonates using field measurements alone were calc-silicates and that chlorophyll associated with endolithic organisms was present in the one rock for which it was predicted. Rocks classified from field spectra as silicics and weathered mafics were recognized in the laboratory as metamorphosed monzonites and diorite schists. This discrepancy was likely due to rock coatings sampled by the field spectrometers compared to fresh rock interiors analyzed petrographically, in addition to somewhat different surfaces analyzed by laboratory thermal spectroscopy compared to field

  7. Savannah River Site Experiences in In Situ Field Measurements of Radioactive Materials

    SciTech Connect

    Moore, F.S.

    1999-10-07

    This paper discusses some of the field gamma-ray measurements made at the Savannah River Site, the equipment used for the measurements, and lessons learned during in situ identification and characterization of radioactive materials.

  8. Building a data set over 12 globally distributed sites to support the development of agriculture monitoring applications with Sentinel-2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Developing better agricultural monitoring capabilities based on Earth Observation data is critical for strengthening food production information and market transparency. The coming Sentinel-2 mission has the optimal capacity for regional to global agriculture monitoring in terms of resolution (10-20...

  9. Field site investigation: Effect of mine seismicity on groundwater hydrology

    SciTech Connect

    Ofoegbu, G.I.; Hsiung, S.; Chowdhury, A.H.; Philip, J.

    1995-04-01

    The results of a field investigation on the groundwater-hydrologic effect of mining-induced earthquakes are presented in this report. The investigation was conducted at the Lucky Friday Mine, a silver-lead-zinc mine in the Coeur d`Alene Mining District of Idaho. The groundwater pressure in sections of three fracture zones beneath the water table was monitored over a 24-mo period. The fracture zones were accessed through a 360-m-long inclined borehole, drilled from the 5,700 level station of the mine. The magnitude, source location, and associated ground motions of mining-induced seismic events were also monitored during the same period, using an existing seismic instrumentation network for the mine, augmented with additional instruments installed specifically for the project by the center for Nuclear Waste Regulatory Analyses (CNWRA). More than 50 seismic events of Richter magnitude 1.0 or larger occurred during the monitoring period. Several of these events caused the groundwater pressure to increase, whereas a few caused it to decrease. Generally, the groundwater pressure increased as the magnitude of seismic event increased; for an event of a given magnitude, the groundwater pressure increased by a smaller amount as the distance of the observation point from the source of the event increased. The data was examined using regression analysis. Based on these results, it is suggested that the effect of earthquakes on groundwater flow may be better understood through mechanistic modeling. The mechanical processes and material behavior that would need to be incorporated in such a model are examined. They include a description of the effect of stress change on the permeability and water storage capacity of a fracture rock mass; transient fluid flow; and the generation and transmission of seismic waves through the rock mass.

  10. Applicability of rapid and on-site measured enzyme activity for surface water quality monitoring in an agricultural catchment

    NASA Astrophysics Data System (ADS)

    Stadler, Philipp; Farnleitner, Andreas H.; Sommer, Regina; Kumpan, Monika; Zessner, Matthias

    2014-05-01

    For the near real time and on-site detection of microbiological fecal pollution of water, the measurement of beta-D- Glucuronidase (GLUC) enzymatic activity has been suggested as a surrogate parameter and has been already successfully operated for water quality monitoring of ground water resources (Ryzinska-Paier et al. 2014). Due to possible short measure intervals of three hours, this method has high potential as a water quality monitoring tool. While cultivation based standard determination takes more than one working day (Cabral 2010) the potential advantage of detecting the GLUC activity is the high temporal measuring resolution. Yet, there is still a big gap of knowledge on the fecal indication capacity of GLUC (specificity, sensitivity, persistence, etc.) in relation to potential pollution sources and catchment conditions (Cabral 2010, Ryzinska-Paier et al. 2014). Furthermore surface waters are a big challenge for automated detection devices in a technical point of view due to the high sediment load during event conditions. This presentation shows results gained form two years of monitoring in an experimental catchment (HOAL) dominated by agricultural land use. Two enzymatic measurement devices are operated parallel at the catchment outlet to test the reproducibility and precision of the method. Data from continuous GLUC monitoring under both base flow and event conditions is compared with reference samples analyzed by standardized laboratory methods for fecal pollution detection (e.g. ISO 16649-1, Colilert18). It is shown that rapid enzymatic on-site GLUC determination can successfully be operated from a technical point of view for surface water quality monitoring under the observed catchment conditions. The comparison of enzyme activity with microbiological standard analytics reveals distinct differences in the dynamic of the signals during event conditions. Cabral J. P. S. (2010) "Water Microbiology. Bacterial Pathogens and Water" International Journal of

  11. FIELD MEASUREMENT OF VAPOR INTRUSION RATES AT A PCE SITE (ABSTRACT ONLY)

    EPA Science Inventory

    A field study was performed to evaluate vapor intrusion (VI) of tetrachloroethylene (PCE) and other chlorinated solvents at a commercial retail site in Dallas, TX. The building is approximately 40 years old and once housed a dry cleaning operation. Results from an initial site ch...

  12. Phosphorus Transport at the Field Scale by Monitoring Groundwater and Interflow Discharge in Hydrologically Sensitive Areas in Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Flores-Lopez, F.; Geohring, L.; Steenhuis, T.

    2004-05-01

    Quantification of nonpoint source of phosphorus losses through agricultural land is important because hydrologically active areas can significantly affect water quality. In this study we examined phosphorus concentration and phosphorus losses from hydrologically sensitive areas and upland areas located in valley soils in the Cannosville basin in Catskill Mountains. Phosphorus concentrations as low as 0.01 - 0.02 mg/L in water increase the algael bloom in lakes and reservoirs and the Cannosville basin is currently restricted to 0.02mg/L. We measured grab surface water samples taken along the creeks to study the phosphorus concentration in the sub-superficial runoff that drains water from the surrounding hills. Also we installed two different transects of piezometers, one line upstream and one line downstream, to study the role of the groundwater component and its effect in the hydrologically sensitive areas. We generally found low phosphorus concentration in the grab surface water samples and the groundwater samples taken in the piezometers. Sampling during the highest creek flow has resulted in the highest concentrations, generally near 0.05 mg/L of dissolved reactive phosphorus. These concentrations were slightly higher than the concentrations in most of the wells, which were around 0.03 mg/L. Sampling is ongoing to determine the effects snow melt contributions. Results will be presented to show the seasonal effects of phosphorus in the hydrologically sensitive areas.

  13. A persistent scatterer interpolation for retrieving accurate ground deformation over InSAR-decorrelated agricultural fields

    NASA Astrophysics Data System (ADS)

    Chen, Jingyi; Zebker, Howard A.; Knight, Rosemary

    2015-11-01

    Interferometric synthetic aperture radar (InSAR) is a radar remote sensing technique for measuring surface deformation to millimeter-level accuracy at meter-scale resolution. Obtaining accurate deformation measurements in agricultural regions is difficult because the signal is often decorrelated due to vegetation growth. We present here a new algorithm for retrieving InSAR deformation measurements over areas with severe vegetation decorrelation using adaptive phase interpolation between persistent scatterer (PS) pixels, those points at which surface scattering properties do not change much over time and thus decorrelation artifacts are minimal. We apply this algorithm to L-band ALOS interferograms acquired over the San Luis Valley, Colorado, and the Tulare Basin, California. In both areas, the pumping of groundwater for irrigation results in deformation of the land that can be detected using InSAR. We show that the PS-based algorithm can significantly reduce the artifacts due to vegetation decorrelation while preserving the deformation signature.

  14. Towards the Development of a Smart Flying Sensor: Illustration in the Field of Precision Agriculture

    PubMed Central

    Hernandez, Andres; Murcia, Harold; Copot, Cosmin; De Keyser, Robin

    2015-01-01

    Sensing is an important element to quantify productivity, product quality and to make decisions. Applications, such as mapping, surveillance, exploration and precision agriculture, require a reliable platform for remote sensing. This paper presents the first steps towards the development of a smart flying sensor based on an unmanned aerial vehicle (UAV). The concept of smart remote sensing is illustrated and its performance tested for the task of mapping the volume of grain inside a trailer during forage harvesting. Novelty lies in: (1) the development of a position-estimation method with time delay compensation based on inertial measurement unit (IMU) sensors and image processing; (2) a method to build a 3D map using information obtained from a regular camera; and (3) the design and implementation of a path-following control algorithm using model predictive control (MPC). Experimental results on a lab-scale system validate the effectiveness of the proposed methodology. PMID:26184205

  15. Towards the Development of a Smart Flying Sensor: Illustration in the Field of Precision Agriculture.

    PubMed

    Hernandez, Andres; Murcia, Harold; Copot, Cosmin; De Keyser, Robin

    2015-01-01

    Sensing is an important element to quantify productivity, product quality and to make decisions. Applications, such as mapping, surveillance, exploration and precision agriculture, require a reliable platform for remote sensing. This paper presents the first steps towards the development of a smart flying sensor based on an unmanned aerial vehicle (UAV). The concept of smart remote sensing is illustrated and its performance tested for the task of mapping the volume of grain inside a trailer during forage harvesting. Novelty lies in: (1) the development of a position-estimation method with time delay compensation based on inertial measurement unit (IMU) sensors and image processing; (2) a method to build a 3D map using information obtained from a regular camera; and (3) the design and implementation of a path-following control algorithm using model predictive control (MPC). Experimental results on a lab-scale system validate the effectiveness of the proposed methodology. PMID:26184205

  16. Investigating summer flow paths in a Dutch agricultural field using high frequency direct measurements

    NASA Astrophysics Data System (ADS)

    Delsman, J. R.; Waterloo, M. J.; Groen, M. M. A.; Groen, J.; Stuyfzand, P. J.

    2014-11-01

    The search for management strategies to cope with projected water scarcity and water quality deterioration calls for a better understanding of the complex interaction between groundwater and surface water in agricultural catchments. We separately measured flow routes to tile drains and an agricultural ditch in a deep polder in the coastal region of the Netherlands, characterized by exfiltration of brackish regional groundwater flow and intake of diverted river water for irrigation and water quality improvement purposes. We simultaneously measured discharge, electrical conductivity and temperature of these separate flow routes at hourly frequencies, disclosing the complex and time-varying patterns and origins of tile drain and ditch exfiltration. Tile drainage could be characterized as a shallow flow system, showing a non-linear response to groundwater level changes. Tile drainage was fed primarily by meteoric water, but still transported the majority (80%) of groundwater-derived salt to surface water. In contrast, deep brackish groundwater exfiltrating directly in the ditch responded linearly to groundwater level variations and is part of a regional groundwater flow system. We could explain the observed salinity of exfiltrating drain and ditch water from the interaction between the fast-responding pressure distribution in the subsurface that determined groundwater flow paths (wave celerity), and the slow-responding groundwater salinity distribution (water velocity). We found water demand for maintaining water levels and diluting salinity through flushing to greatly exceed the actual sprinkling demand. Counterintuitively, flushing demand was found to be largest during precipitation events, suggesting the possibility of water savings by operational flushing control.

  17. Assessment of soil redistribution rates by (137)Cs and (210)Pbex in a typical Malagasy agricultural field.

    PubMed

    Rabesiranana, N; Rasolonirina, M; Solonjara, A F; Ravoson, H N; Raoelina Andriambololona; Mabit, L

    2016-02-01

    Soil degradation processes affect more than one-third of the Malagasy territory and are considered as the major environmental threat impacting the natural resources of the island. This innovative study reports about a pioneer test and use of radio-isotopic techniques (i.e. Cs-137 and Pb-210ex) under Madagascar agroclimatic condition to evaluate soil erosion magnitude. This preliminary investigation has been conducted in a small agricultural field situated in the eastern central highland of Madagascar, 40 km East from Antananarivo. Both anthropogenic Cs-137 and geogenic Pb-210 soil tracers provided similar results highlighting soil erosion rates reaching locally 18 t ha(-1) yr(-1,) a level almost two times higher than the sustainable soil loss rate under Madagascar agroclimatic condition. The sediment delivery ratio established with both radiotracers was above 80% indicating that most of the mobilized sediment exits the field. Assessing soil erosion rate through fallout radionuclides in Madagascar is a first step towards an efficient land and water resource management policy to optimise the effectiveness of future agricultural soil conservation practices. PMID:26691498

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

    NASA Technical Reports Server (NTRS)

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

    1981-01-01

    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.

  19. Waterfowl density on agricultural fields managed to retain water in winter

    USGS Publications Warehouse

    Twedt, D.J.; Nelms, C.O.

    1999-01-01

    Managed water on private and public land provides habitat for wintering waterfowl in the Mississippi Valley, where flood control projects have reduced the area of natural flooding. We compared waterfowl densities on rice, soybean, and moist-soil fields under cooperative agreements to retain water from 1 November through 28 February in Arkansas and Mississippi and assessed temporal changes in waterfowl density during winter in 1991-1992 and 1992-1993. Fields flooded earlier in Arkansas, but retained water later in Mississippi. Over winter, waterfowl densities decreased in Arkansas and increased in Mississippi. Densities of waterfowl, including mallard (Anas platyrhynchos), the most abundant species observed, were greatest on moist-soil fields. However, soybean fields had the greatest densities of northern shoveler (Spatula clypeata).

  20. Enhancement of the Initial Growth Rate of Agricultural Plants by Using Static Magnetic Fields.

    PubMed

    Kim, Seung C; Mason, Alex; Im, Wooseok

    2016-01-01

    Electronic devices and high-voltage wires induce magnetic fields. A magnetic field of 1,300-2,500 Gauss (0.2 Tesla) was applied to Petri dishes containing seeds of Garden Balsam (Impatiens balsamina), Mizuna (Brassica rapa var. japonica), Komatsuna (Brassica rapa var. perviridis), and Mescluns (Lepidium sativum). We applied magnets under the culture dish. During the 4 days of application, we observed that the stem and root length increased. The group subjected to magnetic field treatment (n = 10) showed a 1.4 times faster rate of growth compared with the control group (n = 11) in a total of 8 days (p <0.0005). This rate is 20% higher than that reported in previous studies. The tubulin complex lines did not have connecting points, but connecting points occur upon the application of magnets. This shows complete difference from the control, which means abnormal arrangements. However, the exact cause remains unclear. These results of growth enhancement of applying magnets suggest that it is possible to enhance the growth rate, increase productivity, or control the speed of germination of plants by applying static magnetic fields. Also, magnetic fields can cause physiological changes in plant cells and can induce growth. Therefore, stimulation with a magnetic field can have possible effects that are similar to those of chemical fertilizers, which means that the use of fertilizers can be avoided. PMID:27500712

  1. Field fracturing multi-sites project. Annual technical progress report, July 28, 1993--July 31, 1994

    SciTech Connect

    Not Available

    1995-02-01

    The objective of the Field Fracturing Multi-Sites Project (M-Site) is to conduct experiments to definitively determine hydraulic fracture dimensions using remote well and treatment well diagnostic techniques. In addition, experiments will be conducted to provide data which will resolve significant unknowns with regard to hydraulic fracture modeling, fluid fracture rheology and fracture treatment design. These experiments will be supported by a well-characterized subsurface environment, as well as surface facilities and equipment that are conducive to acquiring high-quality data. The goal is to develop a fully characterized, tight reservoir-typical, field-scale hydraulic-fracturing test site.

  2. Me and My Environment Formative Evaluation Report 1. Arranging Field Tests: Characteristics of Sites and Students.

    ERIC Educational Resources Information Center

    Steele, Joe M.

    The first in a series of evaluation reports gives characteristics of sites and approximately 500 students in field tests of Me and My Environment, a 3-year life science curriculum for 13- to 16-year-old educable mentally handicapped (EMH) adolescents. Described are the field test design, which involves 14 data gathering approaches, and the…

  3. Sites for Student Field Experiences in Refugee Mental Health. Task VI--Training.

    ERIC Educational Resources Information Center

    Hoshino, George; And Others

    This report on sites for student field experiences in refugee mental health has been prepared by the University of Minnesota's Mental Health Technical Assistance Center for the state refugee assistance programs. After a brief introduction describing the mission of the Technical Assistance Center, the characteristics of field experience in mental…

  4. Direct observation of the field-stimulated exoemission sites at tungsten surfaces using field ion microscopy

    NASA Astrophysics Data System (ADS)

    Shiota, T.; Umeno, M.; Dohkuni, K.; Tagawa, M.; Ohmae, N.

    2001-05-01

    The spatial distribution of the field-stimulated exoemission (FSEE) from the W tip surface annealed at 800 K for 600 s and the atomic arrangement of the emitting surface were correlated using field ion microscopy (FIM) and field emission microscopy. The FSEE was observed at around the (111) plane of the annealed W tip surface. FIM observation of the annealed W tip revealed the existence of a pyramid-like protrusion at the W(111) surface. From these experimental results, a new emission model of the FSEE was proposed relating to the field-assisted surface structural change. This model deals with the buildup/collapse of the pyramid-like protrusion at the W(111) surface under the effect of negative high electric field. The temperature dependence of the FSEE reported previously [Shiota et al., J. Appl. Phys. 85, 6811 (1999)] was qualitatively explained by this emission model.

  5. Spatial Variability and Scaling of Infiltration on Undulating Agricultural Terrain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This presentation focuses on surface water infiltration and soil physical properties affecting spatial soil water, nutrient, and plant estimation along with uncertainty and scaling associated with spatial variability. The field site in northeastern Colorado, USA comprises undulating agricultural te...

  6. Long-term monitoring of nitrate-N transport to drainage from three agricultural clayey till fields

    NASA Astrophysics Data System (ADS)

    Ernstsen, V.; Olsen, P.; Rosenbom, A. E.

    2015-01-01

    The application of nitrogen (N) fertilisers to crops grown on tile-drained fields is necessary to sustain most modern crop production, but poses a risk to the aquatic environment since tile drains facilitate rapid transport pathways with no significant reduction in nitrate. To maintain the water quality of the aquatic environment and the provision of food from highly efficient agriculture in line with the EU's Water Framework Directive and Nitrates Directive, field-scale knowledge is imperative if there is to be differentiated N-regulation in future. This study describes nitrate-N leaching to drainage based on coherent monitoring of nitrate-N concentrations, the climate, the groundwater table and crop-specific parameters obtained over eleven years (2001-2011) at three subsurface-drained clayey till fields (1.3-2.3 ha). The monitoring results showed significant field differences in nitrate-N transport to drainage. Not only were these caused by periods of bare soil after short-season crops and N-fixing crops (pea), which have been shown to generate high nitrate-N concentrations in drainage, but by the hydrogeological field conditions that were shown to be the controlling factor of nitrate-N transport to drainage. The fields had the following characteristics: (A) the lowest mass transport (13 kg N ha-1) and fertiliser input had short-term and low-intensity drainage with the highest nitrate-N concentrations detected, representing 40% of net precipitation (226 mm) combined with low air temperatures, (B) the medium mass transport (14 kg N ha-1) had medium-term and medium-intensity drainage, representing 42% of net precipitation (471 mm) combined with periods of both low and higher air temperatures, (C) the highest mass transport (19 kg N ha-1) had long-term drainage, representing 68% of net precipitation (617 mm), but had the highest potential for in-situ soil denitrification and post-treatment (e.g. constructed wetlands) due to long periods with both high water

  7. Polarization signatures for abandoned agricultural fields in the Manix Basin area of the Mojave Desert

    NASA Technical Reports Server (NTRS)

    Ray, Terrill W.; Farr, Tom G.; Vanzyl, Jakob J.

    1991-01-01

    Polarimetric signatures from abandoned circular alfalfa fields in the Manix Basin area of the Mojave desert show systematic changes with length of abandonment. The obliteration of circular planting rows by surface processes could account for the disappearance of bright 'spokes', which seems to be reflection patterns from remnants of the planting rows, with increasing length of abandonment. An observed shift in the location of the maximum L-band copolarization return away from VV, as well as an increase in surface roughness, both occurring with increasing age of abandonment, seems to be attributable to the formation of wind ripple on the relatively vegetationless fields. A Late Pleistocene/Holocene sand bar deposit, which can be identified in the radar images, is probably responsible for the failure of three fields to match the age sequence patterns in roughness and peak shift.

  8. Infrared-temperature variability in a large agricultural field. [Dunnigan, California

    NASA Technical Reports Server (NTRS)

    Millard, J. P.; Goettelman, R. C.; Leroy, M. L. (Principal Investigator)

    1980-01-01

    The combined effect of water carved gullies, varying soil color, moisture state of the soil and crop, nonuniform phenology, and bare spots was measured for commercially grown barley planted on varying terrain. For all but the most rugged terrain, over 80% of the area within 4, 16, 65, and 259 ha cells was at temperatures within 3 C of the mean cell temperature. The result of using relatively small, 4 ha instantaneous field of views for remote sensing applications is that either the worst or the best of conditions is often observed. There appears to be no great advantage in utilizing a small instantaneous field of view instead of a large one for remote sensing of crop canopy temperatures. The two alternatives for design purposes are then either a very high spatial resolution, of the order of a meter or so, where the field is very accurately temperature mapped, or a low resolution, where the actual size seems to make little difference.

  9. Vegetation Water Content Mapping in a Diverse Agricultural Landscape: The National Airborne Field Experiment 2006

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE’06), it is challenging to provide accurate high resolution vegetation i...

  10. Rapid field assessment of RO desalination of brackish agricultural drainage water.

    PubMed

    Thompson, John; Rahardianto, Anditya; Gu, Han; Uchymiak, Michal; Bartman, Alex; Hedrick, Marcos; Lara, David; Cooper, Jim; Faria, Jose; Christofides, Panagiotis D; Cohen, Yoram

    2013-05-15

    Rapid field evaluation of RO feed filtration requirements, selection of effective antiscalant type and dose, and estimation of suitable scale-free RO recovery level were demonstrated using a novel approach based on direct observation of mineral scaling and flux decline measurements, utilizing an automated Membrane Monitor (MeMo). The MeMo, operated in a stand-alone single-pass desalting mode, enabled rapid assessment of the adequacy of feed filtration by enabling direct observation of particulate deposition on the membrane surface. The diagnostic field study with RO feed water of high mineral scaling propensity revealed (via direct MeMo observation) that suspended particulates (even for feed water of turbidity <1 NTU) could serve as seeds for promoting surface crystal nucleation. With feed filtration optimized, a suitable maximum RO water recovery, with complete mineral scale suppression facilitated by an effective antiscalant dose, can be systematically and directly identified (via MeMo) in the field for a given feed water quality. Scale-free operating conditions, determined via standalone MeMo rapid diagnostic tests, were shown to be applicable to spiral-would RO system as validated via both flux decline measurements and ex-situ RO plant membrane scale monitoring. It was shown that the present approach is suitable for rapid field assessment of RO operability and it is particularly advantageous when evaluating water sources of composition that may vary both temporally and across the regions of interest. PMID:23538039

  11. Multi-scale satellite assessment of water availability and agricultural drought: from field to global scales

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper discusses a multi-scale remote sensing modeling system that fuses flux assessments generated with TIR imagery collected by multiple satellite platforms to estimate daily surface fluxes from field to global scales. The Landsat series of polar orbiting systems has collected TIR imagery at 6...

  12. Multi-scale assessment of water availability and agricultural drought: from field to global scales

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Given growing pressures on freshwater resources due to increasing populations, evolving landuse and changing climate, there is a need for timely information on water availability and drought over a wide spectrum of spatial scales: from scales of individual farm fields to inform production decisions...

  13. Field measurement results versus DAYCENT simulations in nitrous oxide emission from agricultural soil in Central Iowa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitrous oxide emissions measured from corn-soybean rotations in Central Iowa were compared with the results obtained from DAYCENT simulations. Available whole year emission field data taken weekly during the growing season and monthly during the winter time, were used. DAYCENT simulations were perfo...

  14. Quantifying variability in field scale evapotranspiration measurements in an irrigated agricultural region under advection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study compares the evapotranspiration (ET) measurements from eddy covariance, lysimetry, and water balance using a network of neutron probe sensors and investigates the role of within-field variability in the vegetation density in explaining the differences among the ET estimates from the vario...

  15. Growing Indian Fig Opuntia on selenium-laden agriculture drainage sediment under field conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growing alternative crops for saline and selenium (Se) impacted lands in arid regions, e.g., Western United States, depends upon the plant’s ability to tolerate the presence of high salts and boron (B). In this field study, we planted 2-month old cacti plants on 30 x 1m beds and evaluated the abilit...

  16. Effects of agricultural practices on greenhouse gas emissions (N2O, CH4 and CO2) from corn fields

    NASA Astrophysics Data System (ADS)

    Hui, D.; Wang, J.; Jima, T.; Dennis, S.; Stockert, C.; Smart, D.; Bhattarai, S.; Brown, K.; Sammis, T.; Reddy, C.

    2012-12-01

    The United States is, by far, the largest producer of corn (Zea mays L.) in the world. Recent increases in fertilizer cost and concerns over global climate change have farmers and others interested in more efficient fertilization management and greenhouse gas emissions reductions. To seek the best management practices, we conducted field experiments during the 2012 growing season at Tennessee State University Agricultural Research and Demonstration Center in Nashville, TN. Six treatments were applied including regular URAN application [2 times], multiple URAN applications [4 times], denitrification inhibitor with regular URAN application, and chicken litter plus regular URAN application in no-tilled plots, and URAN application plus bio-char in tilled plots, all compared to regular URAN application in conventional tilled plots. Each treatment was replicated six times (blocks). We measured N2O, CO2 and CH4 emissions using a closed chamber method after rainfall events, fertilizer applications or every two weeks whichever was shorter. Corresponding soil NH4+-N and NO3--N, soil temperature and moisture were also measured during the gas sampling. Plant physiology and growth were measured about every two weeks. While preliminary results indicate that N2O and CO2 fluxes were significantly influenced by the agricultural practices on some days, particularly after rainfall events, CH4 flux was not influenced by the treatments during most of the days. Plots with bio-char showed significantly lower N2O emissions. We also measured N2O flux in a commercial corn field using the Eddy Covariance (EC) technique to ground verify the chamber based N2O emissions at the field scale. Results obtained with the EC technique seem comparable with the chamber method.

  17. Simulation of water balance in a clayey, subsurface drained agricultural field with three-dimensional FLUSH model

    NASA Astrophysics Data System (ADS)

    Warsta, Lassi; Karvonen, Tuomo; Koivusalo, Harri; Paasonen-Kivekäs, Maija; Taskinen, Antti

    2013-01-01

    SummaryWater flow is a key component in the evaluation of soil erosion and nutrient loads from agricultural fields. Field cultivation is the main non-point pollution source threatening water quality of surface waters in Nordic and many other countries. Few models exist that can describe key hydrological processes in clayey soils, i.e. overland flow, preferential flow in macropores and soil shrinkage and swelling. A new three-dimensional (3-D) distributed numerical model called FLUSH is introduced in this study to simulate these processes. FLUSH describes overland flow with the diffuse wave simplification of the Saint Venant equations and subsurface flow with a dual-permeability approach using the Richards equation in both macropore and matrix pore systems. A method based on the pentadiagonal matrix algorithm solves flow in both macropore and matrix systems directly in a column of cells in the computational grid. Flow between the columns is solved with iteration accelerated with OpenMP parallelisation. The model validity is tested with data from a 3-D analytical model and a clayey subsurface drained agricultural field in southern Finland. According to the simulation results, over 99% of the drainflow originated from the macropore system and drainflow started in some cases within the same hour when precipitation started indicating preferential flow in the profile. The moisture content of the clay soil had a profound effect on runoff distribution between surface runoff and drainflow. In summer, when the soil was dry and cracked, drainflow dominated the total runoff, while in autumn, when the shrinkage crack network had swollen shut, surface runoff fraction clearly increased. Observed differences in surface runoff fraction before and after tillage indicated that the operation decreased hydraulic conductivity of the profile.

  18. Seasonal Dynamics in Runoff Generation, Flowpaths and Phosphorus Mobilization From Reduced-till Agricultural Fields in Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Macrae, M. L.; van Esbroeck, C.; Brunke, R.; McKague, K.

    2014-12-01

    Reduced tillage systems used in agriculture have been shown to decrease losses of particulate phosphorus (P), but may increase the risk of dissolved P transport in some landscapes. Most of our knowledge of P losses from agricultural systems is based on observations made during the frost-free season and little is known about winter processes. Given the magnitude of the spring freshet in many regions, it is important to characterize P dynamics during this period. Discharge and P transport in overland flow and subsurface (tile) drainage were monitored at three reduced-till fields in southern Ontario, Canada for 18 months to (1) quantify runoff and P loads from fields; (2) characterize seasonality in the relative contributions of tile drainage and overland flow to runoff and P loads, and (3) demonstrate variable responses among different event types. Transport pathways were active throughout the non-growing season (NGS) and this period accounted for the majority of annual P loads over the study period. Drainage tiles were the dominant hydrologic pathway from fields throughout the study period, but were a small source of P when compared to P loss in overland flow. Overland flow was predominantly observed during winter thaws when ground frost was present. However, the magnitude and speciation of P losses during individual winter events were variable, and, were governed by a combination of antecedent conditions and precipitation characteristics. Given the importance of the NGS to annual P losses, we suggest that management steps should be taken to minimize the risk of losses during this period.

  19. Aquatic Insect Emergence in Post-Harvest Flooded Agricultural Fields in the Southern San Joaquin Valley, California

    NASA Astrophysics Data System (ADS)

    Moss, R. C.; Blumenshine, S.; Fleskes, J.

    2005-05-01

    California's Southern San Joaquin Valley is one of the most important waterbird areas in North America, but has suffered a disproportionate loss of wetlands when compared to other California regions. This project analyzes the habitat value of post-harvest flooded cropland by measuring the emergence of aquatic insects across multiple crop types. Aquatic insect emergence was sampled from post-harvest flooded fields of four crop types (alfalfa, corn, tomato, wheat), August-October, 2003-2004. Emergence was measured using traps deployed with a stratified random distribution to sample between and within field variation. Emergence rate and emergent biomass was significantly higher in flooded tomato fields. Results from corn fields indicate that flooding depth was correlated (r=0.095) with both diel temperature fluctuation and emergence rate. Chironomus dilutus larvae were grown in environmental chambers, under two thermal treatments with the same mean but different amplitudes (high: 15°-32°C, low: 20°-26°C) to investigate thermal fluctuation effects on survival and biomass. Larval survival (4x) and biomass (2x) were significantly greater in the low versus high temperature fluctuation treatment. This research has the potential to affect agricultural management throughout the 12,600 km2 region, increase aquatic insect production and aid in the recovery of declining bird populations.

  20. 3-D modeling of water balance and soil erosion in a clayey subsurface drained agricultural field in boreal climate

    NASA Astrophysics Data System (ADS)

    Turunen, M.; Warsta, L.; Koivusalo, H. J.; Paasonen-Kivekäs, M.; Nurminen, J.; Myllys, M.; Alakukku, L.; Äijö, H.; Puustinen, M.

    2012-12-01

    Fluxes of nutrients and other substances from cultivated fields cause eutrophication and deterioration of water quality in aquatic ecosystems worldwide. In order to develop effective strategies to control the environmental impacts of crop cultivation, it is crucial to identify the main transport pathways and the effects of different water management methods on the loads. Reduction of sediment loads is essential since sediment particles typically carry nutrients (especially sorbed phosphorus) and other potentially harmful substances, e.g. pesticides, from the fields to the adjacent surface waters. The novel part of this study was the investigation of suspended sediment transport in soil macropores to the subsurface drains and to the deep groundwater. We applied a 3-D distributed dual-permeability model (FLUSH) using a dataset collected from a subsurface drained, clayey agricultural field (15 ha) to holistically assess water balance, soil erosion and sediment transport from the field to an adjacent stream. The data set included five years of hydrological and water quality measurements from four intensively monitored field sections with different soil properties, topography, drainage systems (drain spacing and drain depth), drain installation methods (trenchless and trench drainage) and drain envelope materials (gravel and fiber). The 3-D model allowed us to quantify how soil erosion and sediment transport differed between the field sections within the field area. The simulations were conducted during snow- and frost-free periods. The simulation results include closure of water balance of the cultivated field, distribution of soil erosion and sediment transport within the field area and the effects of different subsurface drainage systems on sediment loads. The 3-D dual-permeability subsurface flow model was able to reproduce the measured drainflows and sediment fluxes in the clayey field and according to the simulations over 90% of drainflow waters were conveyed to

  1. Field sampling and selecting on-site analytical methods for explosives in soil

    SciTech Connect

    Crockett, A.B.; Craig, H.D.; Jenkins, T.F.; Sisk, W.E.

    1996-12-01

    A large number of defense-related sites are contaminated with elevated levels of secondary explosives. Levels of contamination range from barely detectable to levels above 10% that need special handling because of the detonation potential. Characterization of explosives-contaminated sites is particularly difficult because of the very heterogeneous distribution of contamination in the environment and within samples. To improve site characterization, several options exist including collecting more samples, providing on-site analytical data to help direct the investigation, compositing samples, improving homogenization of the samples, and extracting larger samples. This publication is intended to provide guidance to Remedial Project Managers regarding field sampling and on-site analytical methods for detecting and quantifying secondary explosive compounds in soils, and is not intended to include discussions of the safety issues associated with sites contaminated with explosive residues.

  2. Impact of land consolidation and field borders on soil erosion and storage within agricultural landscapes

    NASA Astrophysics Data System (ADS)

    Chartin, Caroline; Salvador-Blanes, Sébastien; Olivier, Evrard; Van Oost, Kristof; Hinschberger, Florent; Macaire, Jean-Jacques

    2014-05-01

    Soil erosion plays an important role in sediment and carbon storage within, and exports from, catchments. In cultivated landscapes, field borders can improve the temporary storage of eroded soil particles and associated carbon, by impeding lateral soil fluxes. These local soil accumulations can lead to the development of linear landforms (such as headlands and lynchets) which will keep evolving after field border removal. A recent study performed in a representative cultivated hillslope of the SW Parisian Basin showed that 39% of the area corresponds to landforms resulting from soil accumulation induced by former and present field borders. This study demonstrated that field borders influence greatly the landscape morphology, but also the spatial distribution of soil thickness, and locally the A-horizon thickness, which are essential parameters for the prediction of SOC stocks. This study aims at characterizing and quantifying the effect of field borders and their removal on medium term topsoil erosion and deposition rates in a cultivated hillslope of the SW Parisian Basin, consolidated in 1967. Here, we used the Cs-137 technique to assess recent patterns of soil redistribution. We measured the Cs-137 inventories of 68 soil cores sampled along transects covering the area and, more specifically, linear landforms identified along present and past field borders (i.e., lynchet and undulation landforms, respectively). Then, we used a spatially-distributed Cs-137 conversion model that simulates and discriminates soil redistribution induced by water and tillage erosion processes over the last fifty years. Finally, observations and model outputs were confronted. Our results show that tillage erosion dominate the soil redistribution in the study area for the 1954-2009 period and generated about 95% (i.e., 4.50 Mg.ha-1.yr-1) of the total gross erosion. Soil redistribution was largely affected by the presence of current and former field borders, where hotspots areas of

  3. Prehistoric Agriculture and Soil Fertility on Lava Flows in Northern Arizona, USA: Results from the San Francisco Volcanic Field REU

    NASA Astrophysics Data System (ADS)

    Broadman, E.; Anderson, K. C.

    2013-12-01

    The San Francisco Volcanic Field in northern Arizona is home to ~600 cinder cones, the youngest of which is Sunset Crater (erupted ~AD 1100). This study documents trends in available phosphate and nitrate content with time, testing whether lowered soil pH from the addition of Sunset cinders increased soil fertility and became a factor in Anasazi agricultural success. Soil fertility is examined both before and after Sunset's eruption in soils of different ages that have developed from eolian deposition on top of lava flows. An increase in phosphate and nitrate levels following acidification would suggest that the presence of Sunset cinders brought the soils to the optimal pH for mobilization of these nutrients. The combined effects of the cinder layer retaining nutrients and water, wetter climates, and increases in phosphate and nitrate (both limiting nutrients for plant growth), would have contributed to Anasazi agricultural success after Sunset's eruption. Samples for this study were taken from eolian-derived soils of different ages atop lava flows in the San Francisco Volcanic Field. OSL data from these soils on Strawberry and SP Craters' lava flows yielded age estimates of ~12.3 ka (Strawberry) and ~32.7 ka (SP), on which a soil chronosequence was based. Results from the chronosequence supported these OSL ages, indicating that soils on the SP flow are older than those on the Strawberry flow. Field descriptions, Harden Development Indices, particle size analysis, and nutrient content analysis were used for this aspect of the project. An experimental acid wash method will be used to simulate the addition of Sunset's acidic cinders, and will yield data for phosphate and nitrate content after Sunset erupted. Preliminary results indicate that phosphate and nitrate accumulate in upper, eolian-derived horizons (Av, Bw) and in more deeply buried carbonate horizons (Bk). Higher concentrations of phosphate and nitrate were found in older (SP) soils than younger

  4. Evaluation of the effects of varying moisture contents on microwave thermal emissions from agriculture fields

    NASA Technical Reports Server (NTRS)

    Burke, H. H. K.

    1980-01-01

    Three tasks related to soil moisture sensing at microwave wavelengths were undertaken: (1) analysis of data at L, X and K sub 21 band wavelengths over bare and vegetated fields from the 1975 NASA sponsored flight experiment over Phoenix, Arizona; (2) modeling of vegetation canopy at microwave wavelengths taking into consideration both absorption and volume scattering effects; and (3) investigation of overall atmospheric effects at microwave wavelengths that can affect soil moisture retrieval. Data for both bare and vegetated fields are found to agree well with theoretical estimates. It is observed that the retrieval of surface and near surface soil moisture information is feasible through multi-spectral and multi-temporal analysis. It is also established that at long wavelengths, which are optimal for surface sensing, atmospheric effects are generally minimal. At shorter wavelengths, which are optimal for atmosheric retrieval, the background surface properties are also established.

  5. Evaluating multiple indices of agricultural water use efficiency and productivity to improve comparisons between sites and trends

    NASA Astrophysics Data System (ADS)

    Levy, M. C.

    2012-12-01

    Approximately 70% of global available freshwater supplies are used in the agricultural sector. Increased demands for water to meet growing population food requirements, and expected changes in the reliability of freshwater supplies due to climate change, threaten the sustainability of water supplies worldwide - not only on farms, but in connected cities and industries. Researchers concerned with agricultural water use sustainability use a variety of theoretical and empirical measures of efficiency and productivity to gain insight into the sustainability of agricultural water use. However, definitions of measures, or indices, vary between different natural and political boundaries, across regions, states and nations and between their respective research, industry, and environmental groups. Index development responds to local data availability and local agendas, and there is debate about the validity of various indices. However, real differences in empirical index measures are not well-understood across the multiple disciplines that study agricultural water use, including engineering and hydrology, agronomy, climate and soil sciences, and economics. Nevertheless reliable, accessible, and generalizable indices are required for planners and policymakers to promote sustainable water use systems. This study synthesizes a set of water use efficiency and productivity indices based on academic, industry and government literature in California and Australia, two locations with similarly water-stressed and valuable agricultural industries under pressure to achieve optimal water use efficiency and productivity. Empirical data at the irrigation district level from the California San Joaquin Valley and Murray Darling Basin states of Victoria and New South Wales in Australia are used to compute indices that estimate efficiency, yield productivity, and economic productivity of agricultural water use. Multiple index estimates of same time-series data demonstrate historical spread

  6. Remote sensing for precision agriculture: Within-field spatial variability analysis and mapping with aerial digital multispectral images

    NASA Astrophysics Data System (ADS)

    Gopalapillai, Sreekala

    2000-10-01

    Advances in remote sensing technology and biological sensors provided the motivation for this study on the applications of aerial multispectral remote sensing in precision agriculture. The feasibility of using high-resolution multispectral remote sensing for precision farming applications such as soil type delineation, identification of crop nitrogen levels, and modeling and mapping of weed density distribution and yield potential within a crop field was explored in this study. Some of the issues such as image calibration for variable lighting conditions and soil background influence were also addressed. Intensity normalization and band ratio methods were found to be adequate image calibration methods to compensate for variable illumination and soil background influence. Several within-field variability factors such as growth stage, field conditions, nutrient availability, crop cultivar, and plant population were found to be dominant in different periods. Unsupervised clustering of color infrared (CIR) image of a field soil was able to identify soil mapping units with an average accuracy of 76%. Spectral reflectance from a crop field was highly correlated to the chlorophyll reading. A regression model developed to predict nitrogen stress in corn identified nitrogen-stressed areas from nitrogen-sufficient areas with a high accuracy (R2 = 0.93). Weed density was highly correlated to the spectral reflectance from a field. One month after planting was found to be a good time to map spatial weed density. The optimum range of resolution for weed mapping was 4 m to 4.5 m for the remote sensing system and the experimental field used in this study. Analysis of spatial yield with respect to spectral reflectance showed that the visible and NIR reflectance were negatively correlated to yield and crop population in heavily weed-infested areas. The yield potential was highly correlated to image indices, especially to normalized brightness. The ANN model developed for one of the

  7. Controls on Nitrogen Fluxes from Agricultural Fields: Differing Conclusions Based on Choice of Sensitivity Analysis Method

    NASA Astrophysics Data System (ADS)

    Ahrens, T.; Matson, P.; Lobell, D.

    2006-12-01

    Sensitivity analyses (SA) of biogeochemical and agricultural models are often used to identify the importance of input variables for variance in model outputs, such as crop yield or nitrate leaching. Identification of these factors can aid in prioritizing efforts in research or decision support. Many types of sensitivity analyses are available, ranging from simple One-At-A-Time (OAT) screening exercises to more complex local and global variance-based methods (see Saltelli et al 2004). The purpose of this study was to determine the influence of the type of SA on factor prioritization in the Yaqui Valley, Mexico using the Water and Nitrogen Management Model (WNMM; Chen et al 2005). WNMM, a coupled plant-growth - biogeochemistry simulation model, was calibrated to reproduce crop growth, soil moisture, and gaseous N emission dynamics in experimental plots of irrigated wheat in the Yaqui Valley, Mexico from 1994-1997. Three types of SA were carried out using 16 input variables, including parameters related to weather, soil properties and crop management. Methods used for SA were local OAT, Monte Carlo (MC), and a global variance-based method (orthogonal input; OI). Results of the SA were based on typical interpretations used for each test: maximum absolute ratio of variation (MAROV) for OAT analyses; first- and second-order regressions for MC analyses; and a total effects index for OI. The three most important factors identified by MC and OI methods were generally in agreement, although the order of importance was not always consistent and there was little agreement for variables of less importance. OAT over-estimated the importance of two factors (planting date and pH) for many outputs. The biggest differences between the OAT results and those from MC and OI were likely due to the inability of OAT methods to account for non-linearity (eg. pH and ammonia volatilization), interactions among variables (eg. pH and timing of fertilization) and an over-reliance on baseline

  8. Particle size distribution and inorganic aerosol characterization during DAURE 2009 winter field campaign at Montseny site

    NASA Astrophysics Data System (ADS)

    Aranzazu Revuelta, M.; Gómez-Moreno, Francisco J.; Plaza, Javier; Coz, Esther; Pey, Jorge; Cusack, Michael; Pandolfi, Marco; Rodríguez-Maroto, Jesús J.; Pujadas, Manuel

    2010-05-01

    During DAURE 2009 winter field campaign, one of the sampling sites was Montseny, a rural background station located 40 km NNE from Barcelona and 25 km W from the Mediterranean Sea. It is a Natural Park and a protected area, thus with low human activity, mainly agriculture. The sampling station was located on a valley with it axis oriented on the direction NW-SE. At this site, a TSI-SMPS (DMA 3071 and CPC 3022) was installed in order to measure the particle number distribution in the size range 15-600 nm during the period March 19-27 with a measurement cycle of 12 minutes The particle mass distribution was measured by a micro-orifice uniform deposit impactor (MOUDI) using eleven size stages with aluminum substrates and a quartz fiber backup filter. Four samples were taken during the period 13-19 March, two during 24 hours and other two during 48 hours. This impactor has a wider size range allowing to measure from 56 to 18000 nm. The substrates and filters obtained were later analyzed for determining soluble ions (sulfate, nitrate, ammonium and calcium) by IC. There are mainly two different kinds of events measured with the SMPS. When the air masses were coming from SE, which meant that they could come from the park but also from the urban and industrial areas located in the pre-coastal depression, it was characterized by higher particle number concentrations and by size distributions centered on 80 nm. This meant it was an aged aerosol, which had grown up by coagulation, condensation and oxidation processes. When the air masses were coming from NW (the second valley axis side), the particle measured were much smaller, the instrument started to detect particles with 15 nm, but smaller ones could be possible. This meant that new particle nucleation could have occurred in the valley, just before arriving to the sampling point. From MOUDI samplings, two different types of events were also observed. Three of the four samplings coincided with stagnation of air masses or

  9. Nitrate transport and fluxes during storm-event discharge from a 12 ha tile-drained dryland agricultural field

    NASA Astrophysics Data System (ADS)

    Kelley, C. J.; Keller, C. K.; Brooks, E. S.; Smith, J. L.; Orr, C. H.; Evans, R. D.

    2012-12-01

    Tile drains shortcut natural soil hydrology and decrease the capacity of soils to buffer water and nutrient fluxes during storm events. Previous research at the Cook Agronomy Farm near Pullman, WA. found seasonal patterns for nutrient and water fluxes, larger during the winter and smaller during the summer. The objective of this study was to determine the effects storm events have on tile-drain water and nutrient fluxes from a dryland agricultural field. Our first hypothesis is that winter storm events activate shallow soil-water flow paths, resulting in rapid transport of precipitation and younger soil pore-water through the tile-drain system. These storm-event flow paths result in a decrease in tile-drain water electrical conductivity from a baseline of approximately 260 μS/cm to as low as 20 μS/ cm. Data suggest that storm events increase hydraulic conductivities in the upper profile as soil approaches saturation, increasing the contributions of relatively young soil water and possibly current storm-event precipitation to tile-drain discharge. Our second hypothesis is that the observed increase in discharge during storm events does not decrease nitrate concentrations in discharged water, because the storm-event flow paths also transport additional nitrate from the upper soil profile through the tile-drain system. If this hypothesis is correct, during storm events nitrate fluxes should increase, indicating rapid mobilization and potential flushing of soil nutrients through the vadose zone and tile-drain. If nitrate fluxes remain constant during storm events, then decreased tile-drain nitrate concentrations may be caused by the addition of low-nitrate or nitrate-free water. This would suggest that the nitrate leached from the system is present at the depth of the tile-drain and is not transported from near the soil surface to the tile-drain during storm-events, indicating flushing of soil nutrients from the rooting zone is not occurring at these temporal scales

  10. On the determination of agricultural prospects using remote sensing and field technique

    NASA Astrophysics Data System (ADS)

    Emetere, Moses Eterigho; Omotosho, T. V.; Olusola, Kayode

    2016-02-01

    The food budget is gradually depleting due to climatic change. The research problem is to see the extent of climate change via catalytic factor e.g. soil compaction. The field work has been reported and the remote sensing technique was used to compliment salient findings established. The Modern Era Retrospective-analysis for Research and Applications (MERRA) was used to obtain five years satellite imagery between 2008 and 2012. The results were used to propound a simple model which shows that the effects of either H >ɛ σ Tr4 or H <ɛ σ Tr4 may be detrimental to crop survival in the nearest future.

  11. Integration of Multiple Field Methods in Characterizing a Field Site with Bayesian Inverse Modeling

    NASA Astrophysics Data System (ADS)

    Savoy, H.; Dietrich, P.; Osorio-Murillo, C. A.; Kalbacher, T.; Kolditz, O.; Ames, D. P.; Rubin, Y.

    2014-12-01

    A hydraulic property of a field can be expressed as a space random function (SRF), and the parameters of that SRF can be constrained by the Method of Anchored Distributions (MAD). MAD is a general Bayesian inverse modeling technique that quantifies the uncertainty of SRF parameters by integrating various direct local data along with indirect non-local data. An example is given with a high-resolution 3D aquifer analog with known hydraulic conductivity (K) and porosity (n) at every location. MAD is applied using different combinations of simulated measurements of K, n, and different scales of hydraulic head that represent different field methods. The ln(K) and n SRF parameters are characterized with each of the method combinations to assess the influence of the methods on the SRFs and their implications. The forward modeling equations are solved by the numerical modeling software OpenGeoSys (opengeosys.org) and MAD is applied with the software MAD# (mad.codeplex.com). The inverse modeling results are compared to the aquifer analog for success evaluation. The goal of the study is to show how integrating combinations of multi-scale and multi-type measurements from the field via MAD can be used to reduce the uncertainty in field-scale SRFs, as well as point values, of hydraulic properties.

  12. Controlling factors of nitrous oxide (N2O) emissions at the field-scale in an agricultural slope

    NASA Astrophysics Data System (ADS)

    Vilain, Guillaume; Garnier, Josette; Tallec, Gaëlle; Tournebize, Julien; Cellier, Pierre; Flipo, Nicolas

    2010-05-01

    Agricultural practices widely contribute to the atmospheric nitrous oxide (N2O) concentration increase and are the major source of N2O which account for 24% of the global annual emission (IPCC, 2007). Soil nitrification and denitrification are the microbial processes responsible for the production of N2O, which also depends on soil characteristics and management. Besides their control by various factors, such as climate, soil conditions and management (content of NO3- and NH4+, soil water content, presence of degradable organic material…), the role of topography is less known although it can play an important role on N2O emissions (Izaurralde et al., 2004). Due to the scarcity of data on N2O direct vs. indirect emission rate from agriculture in the Seine Basin (Garnier et al., 2009), one of the objectives of the study conducted here was to determine the N2O emission rates of the various land use representative for the Seine Basin, in order to better assess the direct N2O emissions, and to explore controlling factor such as meteorology, topography, soil properties and crop successions. The main objective of this study was at the same time to characterize N2O fluxes variability along a transect from an agricultural plateau to a river and to analyze the influence of landscape position on these emissions. We conducted this study in the Orgeval catchment (Seine basin, France; between 48°47' and 48°55' N, and 03°00' and 03°55' E) from May 2008 to August 2009 on two agricultural fields cropped with wheat, barley, oats, corn. N2O fluxes were monitored from weekly to bimonthly using static manual chambers placed along the chosen transect in five different landscape positions from the plateau to the River. This study has shown that soil moisture (expressed as Water Filled Pore Space) and NO3- soil concentrations explained most of the N2O flux variability during the sampling period. Most of N2O was emitted directly after N fertilization application during a relatively

  13. Thresholds of copper phytotoxicity in field-collected agricultural soils exposed to copper mining activities in Chile.

    PubMed

    Verdejo, José; Ginocchio, Rosanna; Sauvé, Sébastien; Salgado, Eduardo; Neaman, Alexander

    2015-12-01

    It has been argued that the identification of the phytotoxic metal thresholds in soil should be based on field-collected soil rather than on artificially-contaminated soils. However, the use of field-collected soils presents several difficulties for interpretation because of mixed contamination and unavoidable covariance of metal contamination with other soil properties that affect plant growth. The objective of this study was to estimate thresholds of copper phytotoxicity in topsoils of 27 agricultural areas historically contaminated by mining activities in Chile. We performed emergence and early growth (21 days) tests (OECD 208 and ISO 11269-2) with perennial ryegrass (Lolium perenne L.). The total Cu content in soils was the best predictor of plant growth and shoot Cu concentrations, while soluble Cu and pCu(2+) did not well correlate with these biological responses. The effects of Pb, Zn, and As on plant responses were not significant, suggesting that Cu is a metal of prime concern for plant growth in soils exposed to copper mining activities in Chile. The effects of soil nutrient availability and shoot nutrient concentrations on ryegrass response were not significant. It was possible to determine EC10, EC25 and EC50 of total Cu in the soil of 327 mg kg(-1), 735 mg kg(-1) and 1144 mg kg(-1), respectively, using the shoot length as a response variable. However, the derived 95% confidence intervals for EC10, EC25 and EC50 values of total soil Cu were wide, and thus not allowing a robust assessment of metal toxicity for agricultural crops, based on total soil Cu concentrations. Thus, plant tests might need to be performed for metal toxicity assessment. This study suggests shoot length of ryegrass as a robust response variable for metal toxicity assessment in contaminated soils with different nutrient availability. PMID:26233921

  14. Occupational exposure to ethylenebisdithiocarbamates in agriculture and allergy: results from the EUROPIT field study.

    PubMed

    Swaen, Gmh; van Amelsvoort, Lgpm; Boers, D; Corsini, E; Fustinoni, S; Vergieva, T; Bosetti, C; Pennanen, S; Liesivuori, J; Colosio, C; van Loveren, H

    2008-09-01

    This epidemiological study was carried out to evaluate the possible association between occupational exposure to ethylenebisdithiocarbamates (EDBC) and allergy. The study was conducted in four countries in the European Union: The Netherlands, Finland, Italy and Bulgaria. A total of 248 workers exposed to EDBC and 231 non-occupationally exposed subjects entered the study. Exposure to EDBC was measured as urinary ethylenethiourea (ETU) in urinary samples collected at baseline and after 30 days of exposure. Several effect parameters were evaluated including questionnaire data on allergy, Phadiatop, a general allergy test, and specific IgE parameters. These data were also collected at baseline and after 30 days of exposure. Cross-sectional as well as longitudinal comparisons were made, adjusted for potential confounding factors. No association was found between exposure status, EDBC levels and allergic contact dermatitis, allergic rhinitis, food allergy or atopy as measured by the Phadiatop. The prevalence of skin irritation was elevated in the Dutch field study only and is more likely a result of plant contact rather than EDBC exposure. Occupational exposure to sunlight was noted to have a protective effect on atopy in terms of IgE positivity. We conclude that the EDBC exposure levels experienced in our field study are not associated with increased prevalence of allergic symptoms or allergy. PMID:19042954

  15. Modelling soil erosion in a clayey, subsurface-drained agricultural field with a three-dimensional FLUSH model

    NASA Astrophysics Data System (ADS)

    Warsta, Lassi; Taskinen, Antti; Koivusalo, Harri; Paasonen-Kivekäs, Maija; Karvonen, Tuomo

    2013-08-01

    Soil erosion is an important environmental issue in agricultural areas of northern Europe where clayey soils are prevalent. Clayey soils are routinely subsurface drained to accelerate drainage which creates an additional discharge route for suspended sediment. Previously, assessment of the sediment load from clayey fields has been difficult, because process-based models were only able to simulate sediment loads via surface runoff. A new distributed, process-based erosion model was developed and incorporated into the FLUSH modelling system to fulfil this void. The model facilitates simulation of spatially distributed soil erosion on the field surface and sediment loads via surface runoff and subsurface drainflow. Soil erosion on the field surface is simulated with the two-dimensional sediment continuity equation coupled with hydraulic and rain drop splash erosion, sediment settling, and transport capacity processes. Subsurface sediment transport in macropores is described with the three-dimensional advection-dispersion equation. The model was applied to a clayey, subdrained field section (∼3.6 ha) in southern Finland. The results demonstrated the capability of the model to simulate soil erosion and sediment transport in terms of the match between the measured (2669 kg ha-1) and modelled (2196 kg ha-1) sediment loads via surface runoff and the measured (2937 kg ha-1) and modelled (2245 kg ha-1) loads via drainflow during the validation period of 7 months. The model sensitivity analysis pointed out the importance of the flow model parameters in simulation of soil erosion through their control on the division of total runoff into surface runoff and drainflow components. The key parameters in the erosion model were those that affected hydraulic and splash erosion rates. The model application in the experimental field suggested that both hydraulic and splash erosion were the factors behind the sediment losses during the growing season and early autumn, whereas high

  16. Traffic Management Advisor: Iterative Field Development and Assessment at Multiple Sites

    NASA Technical Reports Server (NTRS)

    Sanford, Beverly D.; Lee, Katharine K.; Harwood, Kelly; Denery, Dallas G. (Technical Monitor)

    1995-01-01

    Previous studies have demonstrated the necessity of involving users in the development of automation aids, especially for complex domains such as air traffic control (ATC). Traditional development only demanded a single field test to validate a completed system, but a more iterative combination of development and assessment ensures that the technology meets the requirements of its application domain. Exposure across an adequate spectrum of field users is also required during development, and the use of multiple development sites provides an opportunity to consider individual facility cultures as they relate to implementation strategies. The development of the Center/TRACON Automation System (CTAS) Traffic Management Advisor (TMA) at the Denver and Dallas ATC facilities demonstrates successful iterative development and assessment at multiple field sites. The use of field development changes the nature of assessment. As development progresses, periodic assessments are required to validate that system development is progressing along an appropriate track. In the development of the TMA, assessments were performed based on software in the field, and input from traffic managers was analyzed and incorporated into subsequent releases of the TMA, to be reassessed in the field. This has led to a tool with operational suitability and broad user acceptance. Assessment at multiple sites provides a more generalizable perspective that allows the production of a system that is both generic enough to be used at different sites and tailored enough to be of use at any site. In addition to providing a better understanding of specific facility requirements, the use of multiple assessment sites in the development of TMA has provided an opportunity to consider individual facility operations, procedures and cultures as they relate to development and implementation strategies.

  17. Runoff of pharmaceuticals and personal care products following application of biosolids to an agricultural field.

    PubMed

    Topp, Edward; Monteiro, Sara C; Beck, Andrew; Coelho, Bonnie Ball; Boxall, Alistair B A; Duenk, Peter W; Kleywegt, Sonya; Lapen, David R; Payne, Michael; Sabourin, Lyne; Li, Hongxia; Metcalfe, Chris D

    2008-06-15

    Municipal biosolids are a source of nutrients for crop production. Beneficial Management Practices (BMPs) can be used to minimize the risk of contamination of adjacent water resources with chemical or microbial agents that are of public or environmental health concern. In this field study, we applied biosolids slurry at a commercial rate using either subsurface injection or broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 22, 36 and 266 days post-application on 2 m(2) microplots to evaluate surface runoff of 9 model pharmaceuticals and personal care products (PPCPs), atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole and triclosan. In runoff from the injected plots, concentrations of the model PPCPs were generally below the limits of quantitation. In contrast, in the broadcast application treatment, the concentrations of atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, sulfamethoxazole and triclosan on the day following application ranged from 70-1477 ng L(-1) in runoff and generally declined thereafter with first order kinetics. The total mass of PPCPs mobilized in surface runoff per m(2) of the field ranged from 0.63 microg for atenolol to 21.1 microg for ibuprofen. For ibuprofen and acetaminophen, concentrations in runoff first decreased and then increased, suggesting that these drugs were initially chemically or physically sequestered in the biosolids slurry, and subsequently released in the soil. Carbamazepine and triclosan were detected at low concentrations in a runoff event 266 days after broadcast application. Overall, this study showed that injection of biosolids slurry below the soil surface could effectively eliminate surface runoff of PPCPs. PMID:18377955

  18. Nitrogen Cycle Modeling: a Mechanistic Estimate of N-losses From Agricultural Fields Over the Seasonal Time Period

    NASA Astrophysics Data System (ADS)

    Maggi, F.; Gu, C.; Venterea, R.; Riley, W.; Oldenburg, C.

    2007-12-01

    The biogeochemical cycle of nitrogen and production of NO, N2O, and CO2 gas and NO2- and NO3- ions in nutrient-enriched agricultural fields is mediated by soil microbial activity, the hydrological cycle, plant dynamics, and climatic forcing. Understanding how NO, N2O, CO2 gases and NO2- and NO3- ions are released from agricultural fields to the environment is a key factor in controlling the green-house effect and water contamination, and assumes ever greater importance in view of the foreseen increase in biofuel, food, and fiber production. To address these issues we have developed a mechanistic model (TOUGHREACT-N) for various nitrification and denitrification pathways, multiple microbial biomass dynamics, heat and water flows, and various chemical reactions at local and kinetic equilibrium. The soil column is represented in a 1D framework, with hydraulic properties described by a water tension-saturation model. Biotic and abiotic reactions are assumed to follow Michaelis-Menten kinetics, while a consortium of several micro-organismal strains is assumed to follow multiple Monod growth kinetics accounting for electron donor, electron acceptor, and inhibitor concentrations. Water flow is modeled with the Darcy-Richards equation, while nutrient transport is modeled by Fickian advective and diffusive processes in both gaseous and liquid phases. Heat flow is modeled with the Fourier equation. Plant dynamics is taken into account by coupling TOUGHREACT-N with CERES to determine water and nutrient uptake, and soil carbon accumulation. TOUGHREACT-N was calibrated against field measurements to assess pathways of N losses following fertilization. A good agreement between field observations and model predictions was found. We identified two dominant time scales in the system response that depended on plants dynamics. Before plants have substantial impact on soil nutrients and moisture content, N losses are characterized by rapid increases as a function of water application

  19. Estimation of surface energy fluxes using surface renewal and flux variance techniques over an advective irrigated agricultural site

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Estimation of surface energy fluxes over irrigated agriculture is needed to monitor crop water use. Estimates are commonly done using well-established techniques such as eddy covariance (EC) and weighing lysimetry, but implementing these to collect spatially distributed observations is complex and c...

  20. Development of an unmanned aerial vehicle-based remote sensing system for site-specific management in precision agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An Unmanned Aerial Vehicle (UAV) can be remotely controlled or fly autonomously based on pre-programmed flight plans or more complex dynamic automation systems. In agriculture, UAVs have been used for pest control and remote sensing. The objective of this research was to develop a UAV system to en...

  1. Woodlouse locomotor behavior in the assessment of clean and contaminated field sites

    SciTech Connect

    Bayley, M.; Baatrup, E.; Bjerregaard, P.

    1997-11-01

    Specimens of the woodlouse Oniscus asellus were collected at four clean field sites and from a recently closed iron foundry heavily contaminated with zinc, lead, chromium, and nickel. Each of the 30 woodlice per group was housed individually and acclimatized to laboratory conditions for 2 d on a humid plaster of paris substrate. Thereafter, the locomotor behavior of each animal was measured for 4 h employing automated computer-aided video tracking. Linear discriminant analysis of five locomotor parameters revealed average velocity and path length as the principle components separating the polluted site and control animals. Post hoc analysis of the discriminant variable for animals from all five sites showed that the animals from the polluted site where significantly hyperactive when compared to all controls. Further, control animals collected from sites separated by several hundred kilometers were remarkably similar in their locomotor behavior. This preliminary study highlights the potential utility of quantitative analysis of animal locomotor behavior in environmental monitoring.

  2. Rocketdyne division environmental monitoring annual report, Santa Susana Field Laboratory, De Soto, and Canoga Sites, 1990

    SciTech Connect

    none,

    1991-06-20

    This annual report discuses environmental monitoring at three manufacturing and test operations sites operated in the Southern California area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL.), the De Soto site, and the Canoga site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto and Canoga sites are essentially light industry with some laboratory-scale R&D and have little potential impact on the environment. The SSFL site, because of its large size (2,668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling operations with nuclear and radioactive materials, i.e., the U.S. DOE, the U.S. Nuclear Regulatory Commission (NRC), and the California State Department of Health Services (DHS), Radiologic Health Branch (RHB). For that reason, information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major realm of interest is radiological, this report also includes some discussion of nonradiological monitoring at SSFL

  3. Extreme electric fields power catalysis in the active site of ketosteroid isomerase

    PubMed Central

    Fried, Stephen D.; Bagchi, Sayan; Boxer, Steven G.

    2015-01-01

    Enzymes use protein architecture to impose specific electrostatic fields onto their bound substrates, but the magnitude and catalytic effect of these electric fields have proven difficult to quantify with standard experimental approaches. Using vibrational Stark effect spectroscopy, we found that the active site of the enzyme ketosteroid isomerase (KSI) exerts an extremely large electric field onto the C=O chemical bond that undergoes a charge rearrangement in KSI’s rate-determining step. Moreover, we found that the magnitude of the electric field exerted by the active site strongly correlates with the enzyme’s catalytic rate enhancement, enabling us to quantify the fraction of the catalytic effect that is electrostatic in origin. The measurements described here may help explain the role of electrostatics in many other enzymes and biomolecular systems. PMID:25525245

  4. Statistical analysis of nitrous oxide emission factors from pastoral agriculture field trials conducted in New Zealand.

    PubMed

    Kelliher, F M; Cox, N; van der Weerden, T J; de Klein, C A M; Luo, J; Cameron, K C; Di, H J; Giltrap, D; Rys, G

    2014-03-01

    Between 11 May 2000 and 31 January 2013, 185 field trials were conducted across New Zealand to measure the direct nitrous oxide (N2O) emission factors (EF) from nitrogen (N) sources applied to pastoral soils. The log(EF) data were analysed statistically using a restricted maximum likelihood (REML) method. To estimate mean EF values for each N source, best linear unbiased predictors (BLUPs) were calculated. For lowland soils, mean EFs for dairy cattle urine and dung, sheep urine and dung and urea fertiliser were 1.16 ± 0.19% and 0.23 ± 0.05%, 0.55 ± 0.19% and 0.08 ± 0.02% and 0.48 ± 0.13%, respectively, each significantly different from one another (p < 0.05), except for sheep urine and urea fertiliser. For soils in terrain with slopes >12°, mean EFs were significantly lower. Thus, urine and dung EFs should be disaggregated for sheep and cattle as well as accounting for terrain. PMID:24361566

  5. Micrometeorological and ammonia gradient measurements above agricultural fields in Turew (Poland)

    NASA Astrophysics Data System (ADS)

    Weidinger, T.; Pogany, A.; Janku, K.; Wasilewsky, J.; Mohacsi, A.; Bozoki, Z.; Gyongyosi, A. Z.; Istenes, Z.; Eredics, A.; Bordas, A.

    2009-04-01

    Two joint Polish-Hungarian field campaigns were performed close beside cattle farms, near Turew (Poland), with the idea to determine energy budget components above cropland and to estimate ammonia flux. The first campaign was performed above grassland with limited fetch (close shelter belt) in June 2008, the second above arable cropland in October 2008. Turbulent fluxes were calculated using micrometeorological measurement data (standard meteorological parameters, radiation and surface energy budget components) as well as three different methods: (i) the gradient, (ii) the Bowen ratio and (iii) the eddy covariance method. Results obtained using different methodologies for flux calculations and local effects on energy budget closure were compared. During the second campaign concentration of ammonia was measured employing three different instruments: (i) a passive sampler, (ii) the AMANDA system and (iii) a diode laser based photoacoustic instrument combined with preconcentration sampling (WaSul-Flux). These measurements provide data for ammonia flux calculation on landscape scale. Data obtained using the AMANDA system and the photoacoustic instrument was used to determine vertical and horizontal distribution of ammonia concentration. Ammonia fluxes were calculated using gradient and profile method. Sensitivity analysis of the ammonia flux calculation [(i) assessment of ammonia gradient, (ii) choice of universal function, (iii) application of gradient and profile techniques], daily variations of the energy budget components and the effects of ammonia emission from the cattle farm were also investigated.

  6. Research Highlights and Recent Enhancements at the NEES@UCSB Permanently Instrumented Field Sites

    NASA Astrophysics Data System (ADS)

    Steidl, J. H.; Hegarty, P.; Seale, S. H.; Lamere, T.; Stinson, E.; Wojcik, K.

    2012-12-01

    The NEES@UCSB facility consists of experimental facilities and cyber infrastructure for active testing and passive earthquake monitoring at instrumented geotechnical field sites. There have been a number of facility enhancements to both the experimental facilities and the cyber infrastructure for facilitating research at the sites and access to the data they produce. Through both the maintenance and operations and the NEES Research program funding sources, the scope of monitoring at the field sites continues to expand. A permanent cross-hole source and sensor array has been installed at both the Wildlife Liquefaction Array (WLA) and at the Garner Valley Downhole Array (GVDA) field sites. This enhancement provides daily measurements of shear-wave velocity and automated post-earthquake observations of velocity to examine soil modulus reduction and recovery. After a very large event, where nonlinear soil behavior is expected, cross-hole hammer source time intervals are as short as 5 minutes. While waiting for larger earthquakes to occur, the daily cross-hole hammer tests are providing interesting data on shear-wave velocity changes with seasonal water table height. Testing of a small reconfigurable structure at both the WLA and GVDA sites was conducted using the NEES@UCLA mobile shakers. The structure, which is a smaller version of a permanent structure at GVDA, has been left at the GVDA site and can be used for future experiments or site instrumentation enhancements. The large soil-foundation-interaction structure at GVDA has a 1D shaker mounted under its roof slab. This shaker runs nightly and the data provide insight into the influence of environmental conditions on the response of the structure. At WLA, additional sensors have been installed in a dense Shape Accelerometer Array (SAA). Each of the seven arrays contain 24 3-component MEMS accelerometers at approximately 0.3 meter spacing that span the upper 8 meters of the site, from above to below the liquefiable

  7. Effective removal of field-emitting sites from metallic surfaces by dry ice cleaning

    SciTech Connect

    Dangwal, Arti; Mueller, Guenter; Reschke, Detlef; Floettmann, Klaus; Singer, Xenia

    2007-08-15

    Systematic results of the field emission properties of polycrystalline copper and niobium and single-crystal Nb are reported. Dry ice cleaning (DIC) is found to suppress enhanced field emission from metallic surfaces. The cleaning effect on the emitting sites was investigated by means of field emission scanning microscopy up to fields of 250 MV/m and high-resolution scanning electron microscopy with energy dispersive x-ray analysis. The number density of emitters at given fields was drastically reduced by dry ice cleaning. Current-voltage measurements and derived Fowler-Nordheim parameters are partially discussed with respect to the morphology and impurity content of localized emitters. No emission from grain boundaries on large-grain Nb samples was observed. The microscopy results prove the effective removal of field-emitting particulates down to 400 nm as well as the partial smoothing of surface protrusions by DIC.

  8. Modelling in situ enzyme potential of soils: a tool to predict soil respiration from agricultural fields

    NASA Astrophysics Data System (ADS)

    Shahbaz Ali, Rana; Poll, Christian; Demyan, Scott; Nkwain Funkuin, Yvonne; Ingwersen, Joachim; Wizemann, Hans-Dieter; Kandeler, Ellen

    2014-05-01

    temperatures. Q10 of β-glucosidase activity changed significantly across the year (Q10 values ranges from 1.5 to 2.0 in Kraichgau and 1.6 to 2.1 in Swabian Alb), while for xylanase activity, no significant effects were found (Q10 values ranges from 1.2 to 3.0 in Kraichgau and 1.3 to 3.3 in Swabian Alb) in both study regions. By using laboratory based enzyme activities, calculated Q10 values, and daily soil temperature data, we modelled in situ enzyme potentials in soils for labile and recalcitrant carbon pools for both study regions. We observed an increase in modelled in situ enzyme activities during the summer period and a substantial decrease during winter indicating temperature as a strong controlling factor. A significant higher positive correlation of soil surface CO2 flux with modelled in situ β-glucosidase activity was found in both study regions compared to modelled in situ xylanase activity. These results demonstrate that (1) Q10 values are site and season specific and should be added into carbon models and (2) the indication of the relevance of greater contribution of labile carbon pool to soil CO2 emissions.

  9. Field-based evidence for consistent responses of bacterial communities to copper contamination in two contrasting agricultural soils

    PubMed Central

    Li, Jing; Ma, Yi-Bing; Hu, Hang-Wei; Wang, Jun-Tao; Liu, Yu-Rong; He, Ji-Zheng

    2015-01-01

    Copper contamination on China's arable land could pose severe economic, ecological and healthy consequences in the coming decades. As the drivers in maintaining ecosystem functioning, the responses of soil microorganisms to long-term copper contamination in different soil ecosystems are still debated. This study investigated the impacts of copper gradients on soil bacterial communities in two agricultural fields with contrasting soil properties. Our results revealed consistent reduction in soil microbial biomass carbon (SMBC) with increasing copper levels in both soils, coupled by significant declines in bacterial abundance in most cases. Despite of contrasting bacterial community structures between the two soils, the bacterial diversity in the copper-contaminated soils showed considerably decreasing patterns when copper levels elevated. High-throughput sequencing revealed copper selection for major bacterial guilds, in particular, Actinobacteria showed tolerance, while Acidobacteria and Chloroflexi were highly sensitive to copper. The thresholds that bacterial communities changed sharply were 800 and 200 added copper mg kg−1 in the fluvo-aquic soil and red soil, respectively, which were similar to the toxicity thresholds (EC50 values) characterized by SMBC. Structural equation model (SEM) analysis ascertained that the shifts of bacterial community composition and diversity were closely related with the changes of SMBC in both soils. Our results provide field-based evidence that copper contamination exhibits consistently negative impacts on soil bacterial communities, and the shifts of bacterial communities could have largely determined the variations of the microbial biomass. PMID:25699026

  10. Health system reform and the role of field sites based upon demographic and health surveillance.

    PubMed Central

    Tollman, S. M.; Zwi, A. B.

    2000-01-01

    Field sites for demographic and health surveillance have made well-recognized contributions to the evaluation of new or untested interventions, largely through efficacy trials involving new technologies or the delivery of selected services, e.g. vaccines, oral rehydration therapy and alternative contraceptive methods. Their role in health system reform, whether national or international, has, however, proved considerably more limited. The present article explores the characteristics and defining features of such field sites in low-income and middle-income countries and argues that many currently active sites have a largely untapped potential for contributing substantially to national and subnational health development. Since the populations covered by these sites often correspond with the boundaries of districts or subdistricts, the strategic use of information generated by demographic surveillance can inform the decentralization efforts of national and provincial health authorities. Among the areas of particular importance are the following: making population-based information available and providing an information resource; evaluating programmes and interventions; and developing applications to policy and practice. The question is posed as to whether their potential contribution to health system reform justifies arguing for adaptations to these field sites and expanded investment in them. PMID:10686747

  11. Chemical and biological characterization of products of incomplete combustion from the simulated field burning of agricultural plastic

    SciTech Connect

    Linak, W.P.; Ryan, J.V.; Perry, E.; Williams, R.W.; DeMarini, D.M.

    1989-06-01

    Chemical and biological analyses were performed to characterize products of incomplete combustion emitted during the simulated open field burning of agricultural plastic. A small utility shed equipped with an air delivery system was used to simulate pile burning and forced-air-curtain incineration of a nonhalogenated agricultural plastic that reportedly consisted of polyethylene and carbon black. Emissions were analyzed for combustion gases; volatile, semi-volatile, and particulate organics; and toxic and mutagenic properties. Emission samples, as well as samples of the used (possibly pesticide-contaminated) plastic, were analyzed for the presence of several pesticides to which the plastic may have been exposed. Although a variety of alkanes, alkenes, and aromatic and polycyclic aromatic hydrocarbon (PAH) compounds were identified in the volatile, semi-volatile, and particulate fractions of these emissions, a substantial fraction of higher molecular weight organic material was not identified. No pesticides were identified in either combustion emission samples or dichloromethane washes of the used plastic. When mutagenicity was evaluated by exposing Salmonella bacteria (Ames assay) to whole vapor and vapor/particulate emissions, no toxic or mutagenic effects were observed. However, organic extracts of the particulate samples were moderately mutagenic. This mutagenicity compares approximately to that measured from residential wood heating on a revertant per unit heat release basis. Compared to pile burning, forced air slightly decreased the time necessary to burn a charge of plastic. There was not a substantial difference, however, in the variety or concentrations of organic compounds identified in samples from these two burn conditions. This study highlights the benefits of a combined chemical/biological approach to the characterization of complex, multi-component combustion emissions.

  12. MGS-TES Phase Effects and Thermal Infrared Directional Emissivity Field Measurements of Martian Analog Sites

    NASA Astrophysics Data System (ADS)

    Pitman, K. M.; Bandfield, J. L.; Wolff, M. J.

    2006-03-01

    We present a set of on- and off-nadir thermal IR field and laboratory emissivity spectra for three undisturbed Mars terrain analog sites and analyze them for presence or absence of directional emissivity effects. Comparisons to moderate and low albedo surface MGS-TES EPF sequences are discussed.

  13. Upscaling of point soil moisture measurements to field averages at the OPE3 test site.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To better understand how point soil moisture values relate to field-scale estimates of soil moisture a comprehensive evaluation of soil water dynamics was studied at the Optimizing Production Inputs for Economic and Environmental Enhancement (OPE3) research site in Beltsville, Maryland. The ranking...

  14. Field fracturing multi-sites project. Annual report, August 1, 1995--July 31, 1996

    SciTech Connect

    1996-12-31

    The objective of the Field Fracturing Multi-Sites Project (M-Site) is to conduct experiments to definitively determine hydraulic fracture dimensions using remote well and treatment well diagnostic techniques. In addition, experiments are to be conducted to provide data that will resolve significant unknowns with regard to hydraulic fracture modeling, fracture fluid rheology and fracture treatment design. These experiments will be supported by a well-characterized subsurface environment, as well as surface facilities and equipment conducive to acquiring high-quality data. The primary Project goal is to develop a fully characterized, tight reservoir-typical, field-scale hydraulic fracturing test site to diagnose, characterize, and test hydraulic fracturing technology and performance. It is anticipated that the research work being conducted by the multi-disciplinary team of GRI and DOE contractors will lead to the development of a commercial fracture mapping tool/service.

  15. Oscillatory Hydraulic Tomography at the Field Scale: Boise Hydrogeophysical Research Site

    NASA Astrophysics Data System (ADS)

    Lim, D.; Barrash, W.; Cardiff, M. A.

    2015-12-01

    The use of sinusoidal or periodic testing for field-scale tomography of aquifer parameters (conductivity / storativity) is a novel, minimally-invasive method for aquifer characterization between boreholes. Previous results have demonstrated the effectiveness of this method, which we name Oscillatory Hydraulic Tomography (OHT), through both numerical and laboratory experiments. However, implementation and analysis of field-scale OHT testing has not been achieved to-date, and thus the technique remains unproven for application in real-world aquifers. We present an evaluation of OHT at the field scale here through application at the Boise Hydrogeophysical Research Site (BHRS), a field-scale (~20m diameter x 20m thickness) research site. Through Bayesian inversion, we assess issues such as data quality impacts and resolution of obtained tomographic images. We discuss issues associated with both data collection and data processing, and based on our experiences suggest a workflow for OHT performance at other field sites. The advantages of OHT, relative to "traditional" hydraulic tomography with constant rate pumping tests, include the ability to test across a range of stimulation frequencies (obtaining increased heterogeneity information), very high signal-to-noise ratios. Additionally, we examine the impact of nonlinear effects - such as water table boundary conditions - and their impact on OHT analysis algorithms.

  16. Effects of agricultural tillage practise on green house gas balance of an arable soil in a long term field experiment

    NASA Astrophysics Data System (ADS)

    Munch, Jean Charles; Schilling, Rolf; Ruth, Bernhard; Fuss, Roland

    2010-05-01

    Soils are an important part of the global carbon cycle. A large proportion of global carbon dioxide (CO2) emissions is released from soils, though carbon sequestration occurs. Nitrous oxide (N2O) emissions of soils are also believed to contribute significantly to the green house effect as well as the stratospheric ozone depletion. An important source of N2O emissions is denitrification of nitrate from nitrogen fertilized soils. Although it is desirable to minimize these emissions while maintaining high crop yields it is still poorly understood how green house gas emissions may be steered by agricultural management practise, i.e. tillage and fertilization systems . In an ongoing long term field experiment at the research farm Scheyern, Bavaria, a arable field with one homogenous soil formation was transformed into plots in a randomized design 14 years ago. Since then, they are managed using conventional tillage (CT) and no tillage (NT) as well as low and high fertilization. A conventional crop rotation is maintained on the field. Starting 2007, CO2 and N2O emissions were monitored continuously for 2.5 years. Furthermore water content, temperature and redox potential were measured in-situ as they are major factors on microbial activity and denitrification. Soil was sampled from the Ap horizons of the plots about twice a month and extracts from these soil samples were analyzed for dissolved organic carbon (DOC), ammonium, nitrate/nitrite, and dissolved organic nitrogen (DON). According to the results soil density and hydrology are clearly affected by tillage practise. DOC is more affected by tillage while concentration of nitrogen species is controlled mainly by fertilization. There are distinct differences in redox potential between CT and NT plots with CT plots having more anaerobic periods. CO2 and N2O emissions exhibit a clear seasonal pattern and are affected by both tillage system and fertilization

  17. Are BVOC exchanges in agricultural ecosystems overestimated? Insights from fluxes measured in a maize field over a whole growing season

    NASA Astrophysics Data System (ADS)

    Bachy, Aurélie; Aubinet, Marc; Schoon, Niels; Amelynck, Crist; Bodson, Bernard; Moureaux, Christine; Heinesch, Bernard

    2016-04-01

    Although maize is the second most important crop worldwide, and the most important C4 crop, no study on biogenic volatile organic compounds (BVOCs) has yet been conducted on this crop at ecosystem scale and over a whole growing season. This has led to large uncertainties in cropland BVOC emission estimations. This paper seeks to fill this gap by presenting, for the first time, BVOC fluxes measured in a maize field at ecosystem scale (using the disjunct eddy covariance by mass scanning technique) over a whole growing season in Belgium. The maize field emitted mainly methanol, although exchanges were bi-directional. The second most exchanged compound was acetic acid, which was taken up mainly in the growing season. Bi-directional exchanges of acetaldehyde, acetone and other oxygenated VOCs also occurred, whereas the terpenes, benzene and toluene exchanges were small, albeit significant. Surprisingly, BVOC exchanges were of the same order of magnitude on bare soil and on well developed vegetation, suggesting that soil is a major BVOC reservoir in agricultural ecosystems. Quantitatively, the maize BVOC emissions observed were lower than those reported in other maize, crops and grasses studies. The standard emission factors (SEFs) estimated in this study (231 ± 19 µg m-2 h-1 for methanol, 8 ± 5 µg m-2 h-1 for isoprene and 4 ± 6 µg m-2 h-1 for monoterpenes) were also much lower than those currently used by models for C4 crops, particularly for terpenes. These results suggest that maize fields are small BVOC exchangers in north-western Europe, with a lower BVOC emission impact than that modelled for growing C4 crops in this part of the world. They also reveal the high variability in BVOC exchanges across world regions for maize and suggest that SEFs should be estimated for each region separately.

  18. Numerical modeling of field tests in unsaturated fractured basalt at the Box Canyon site

    SciTech Connect

    Doughty, C.

    1998-05-01

    A TOUGH2 model of a ponded infiltration test has been developed and used to predict the results of a field experiment conducted in the vadose zone of the fractured Snake River Plain basalts, at the Box Canyon site in southeastern idaho. The key question addressed is how fracture-pattern characteristics and connectivity affect the pattern of liquid infiltration. The numerical model, a two-dimensional vertical cross-section, uses half-meter discretization for the shallow field site, which extends about 20 m from the ground surface to an underlying perched water body. The model includes explicit but highly simplified representations of major fractures and other important hydrological features. It adequately reproduces the majority of the field observations, confirming the notion that infiltration is largely fracture-controlled.

  19. Demonstration and validation of automated agricultural field extraction from multi-temporal Landsat data for the majority of United States harvested cropland

    NASA Astrophysics Data System (ADS)

    Yan, L.; Roy, D. P.

    2014-12-01

    The spatial distribution of agricultural fields is a fundamental description of rural landscapes and the location and extent of fields is important to establish the area of land utilized for agricultural yield prediction, resource allocation, and for economic planning, and may be indicative of the degree of agricultural capital investment, mechanization, and labor intensity. To date, field objects have not been extracted from satellite data over large areas because of computational constraints, the complexity of the extraction task, and because consistently processed appropriate resolution data have not been available or affordable. A recently published automated methodology to extract agricultural crop fields from weekly 30 m Web Enabled Landsat data (WELD) time series was refined and applied to 14 states that cover 70% of harvested U.S. cropland (USDA 2012 Census). The methodology was applied to 2010 combined weekly Landsat 5 and 7 WELD data. The field extraction and quantitative validation results are presented for the following 14 states: Iowa, North Dakota, Illinois, Kansas, Minnesota, Nebraska, Texas, South Dakota, Missouri, Indiana, Ohio, Wisconsin, Oklahoma and Michigan (sorted by area of harvested cropland). These states include the top 11 U.S states by harvested cropland area. Implications and recommendations for systematic application to global coverage Landsat data are discussed.

  20. Characteristics of Ambient Black Carbon Mass and Size-Resolved Particle Number Concentrations during Corn Straw Open-Field Burning Episode Observations at a Rural Site in Southern Taiwan

    PubMed Central

    Cheng, Yu-Hsiang; Yang, Li-Sing

    2016-01-01

    Information on the effect of open-field burning of agricultural residues on ambient black carbon (BC) mass and size-resolved particle number concentrations is scarce. In this study, to understand the effect of such open-field burning on short-term air quality, real-time variations of the BC mass and size-resolved particle number concentrations were monitored before and during a corn straw open-field burning episode at a rural site. Correlations between the BC mass and size-resolved particle number concentrations during the episode were investigated. Moreover, the particle number size distribution and absorption Ångström exponent were determined for obtaining the characteristics of aerosol emissions from the corn straw open-field burning. The results can be used to address public health concerns and as a reference for managing similar episodes of open-field burning of agricultural residues. PMID:27399754

  1. Characteristics of Ambient Black Carbon Mass and Size-Resolved Particle Number Concentrations during Corn Straw Open-Field Burning Episode Observations at a Rural Site in Southern Taiwan.

    PubMed

    Cheng, Yu-Hsiang; Yang, Li-Sing

    2016-01-01

    Information on the effect of open-field burning of agricultural residues on ambient black carbon (BC) mass and size-resolved particle number concentrations is scarce. In this study, to understand the effect of such open-field burning on short-term air quality, real-time variations of the BC mass and size-resolved particle number concentrations were monitored before and during a corn straw open-field burning episode at a rural site. Correlations between the BC mass and size-resolved particle number concentrations during the episode were investigated. Moreover, the particle number size distribution and absorption Ångström exponent were determined for obtaining the characteristics of aerosol emissions from the corn straw open-field burning. The results can be used to address public health concerns and as a reference for managing similar episodes of open-field burning of agricultural residues. PMID:27399754

  2. Evaluation of measurement reproducibility using the standard-sites data, 1994 Fernald field characterization demonstration project

    SciTech Connect

    Rautman, C.A.

    1996-02-01

    The US Department of Energy conducted the 1994 Fernald (Ohio) field characterization demonstration project to evaluate the performance of a group of both industry-standard and proposed alternative technologies in describing the nature and extent of uranium contamination in surficial soils. Detector stability and measurement reproducibility under actual operating conditions encountered in the field is critical to establishing the credibility of the proposed alternative characterization methods. Comparability of measured uranium activities to those reported by conventional, US Environmental Protection Agency (EPA)-certified laboratory methods is also required. The eleven (11) technologies demonstrated included (1) EPA-standard soil sampling and laboratory mass-spectroscopy analyses, and currently-accepted field-screening techniques using (2) sodium-iodide scintillometers, (3) FIDLER low-energy scintillometers, and (4) a field-portable x-ray fluorescence spectrometer. Proposed advanced characterization techniques included (5) alpha-track detectors, (6) a high-energy beta scintillometer, (7) electret ionization chambers, (8) and (9) a high-resolution gamma-ray spectrometer in two different configurations, (10) a field-adapted laser ablation-inductively coupled plasma-atomic emission spectroscopy (ICP-AES) technique, and (11) a long-range alpha detector. Measurement reproducibility and the accuracy of each method were tested by acquiring numerous replicate measurements of total uranium activity at each of two ``standard sites`` located within the main field demonstration area. Meteorological variables including temperature, relative humidity. and 24-hour rainfall quantities were also recorded in conjunction with the standard-sites measurements.

  3. Off-site impacts of agricultural composting: role of terrestrially derived organic matter in structuring aquatic microbial communities and their metabolic potential.

    PubMed

    Pommier, Thomas; Merroune, Asmaa; Bettarel, Yvan; Got, Patrice; Janeau, Jean-Louis; Jouquet, Pascal; Thu, Thuy D; Toan, Tran D; Rochelle-Newall, Emma

    2014-12-01

    While considered as sustainable and low-cost agricultural amendments, the impacts of organic fertilizers on downstream aquatic microbial communities remain poorly documented. We investigated the quantity and quality of the dissolved organic matter leaching from agricultural soil amended with compost, vermicompost or biochar and assessed their effects on lake microbial communities, in terms of viral and bacterial abundances, community structure and metabolic potential. The addition of compost and vermicompost significantly increased the amount of dissolved organic carbon in the leachate compared with soil alone. Leachates from these additions, either with or without biochar, were highly bioavailable to aquatic microbial communities, although reducing the metabolic potential of the community and harbouring more specific communities. Although not affecting bacterial richness or taxonomic distributions, the specific addition of biochar affected the original lake bacterial communities, resulting in a strongly different community. This could be partly explained by viral burst and converging bacterial abundances throughout the samples. These results underline the necessity to include off-site impacts of agricultural amendments when considering their cascading effect on downstream aquatic ecosystems. PMID:25195703

  4. Controlling activation site density by low-energy far-field stimulation in cardiac tissue

    NASA Astrophysics Data System (ADS)

    Hörning, Marcel; Takagi, Seiji; Yoshikawa, Kenichi

    2012-06-01

    Tachycardia and fibrillation are potentially fatal arrhythmias associated with the formation of rotating spiral waves in the heart. Presently, the termination of these types of arrhythmia is achieved by use of antitachycardia pacing or cardioversion. However, these techniques have serious drawbacks, in that they either have limited application or produce undesirable side effects. Low-energy far-field stimulation has recently been proposed as a superior therapy. This proposed therapeutic method would exploit the phenomenon in which the application of low-energy far-field shocks induces a large number of activation sites (“virtual electrodes”) in tissue. It has been found that the formation of such sites can lead to the termination of undesired states in the heart and the restoration of normal beating. In this study we investigate a particular aspect of this method. Here we seek to determine how the activation site density depends on the applied electric field through in vitro experiments carried out on neonatal rat cardiac tissue cultures. The results indicate that the activation site density increases exponentially as a function of the intracellular conductivity and the level of cell isotropy. Additionally, we report numerical results obtained from bidomain simulations of the Beeler-Reuter model that are quantitatively consistent with our experimental results. Also, we derive an intuitive analytical framework that describes the activation site density and provides useful information for determining the ratio of longitudinal to transverse conductivity in a cardiac tissue culture. The results obtained here should be useful in the development of an actual therapeutic method based on low-energy far-field pacing. In addition, they provide a deeper understanding of the intrinsic properties of cardiac cells.

  5. Effects of NO3 (-) and PO4 (3-) on the release of geogenic arsenic and antimony in agricultural wetland soil: a field and laboratory approach.

    PubMed

    Rouwane, Asmaa; Rabiet, Marion; Grybos, Malgorzata; Bernard, Guillaume; Guibaud, Gilles

    2016-03-01

    The dynamics of arsenic (As) and antimony (Sb) in wetland soil periodically submitted to agricultural pressure as well as the impact of soil enrichment with NO3 (-) (50 mg L(-1)) and PO4 (3-) (20 mg L(-1)) on As and Sb release were evaluated at both field and laboratory scales. The results showed that As and Sb exhibited different temporal behaviors, depending on the study scale. At field scale, As release (up to 93 μg L(-1)) occurred under Fe-reducing conditions, whereas Sb release was favored under oxidizing conditions (up to 5 μg L(-1)) and particularity when dissolved organic carbon (DOC) increased in soil pore water (up to 92.8 mg L(-1)). At laboratory scale, As and Sb release was much higher under reducing conditions (up to 138 and 1 μg L(-1), respectively) compared to oxic conditions (up to 6 and 0.5 μg L(-1), respectively) and was enhanced by NO3 (-) and PO4 (3-) addition (increased by a factor of 2.3 for As and 1.6 for Sb). The higher release of As and Sb in the enriched reduced soil compared to the non-enriched soil was probably induced by the combined effect of PO4 (3-) and HCO3 (-) which compete for the same binding sites of soil surfaces. Modeling results using Visual Minteq were in accordance with experimental results regarding As but failed in simulating the effects of PO4 (3-) and HCO3 (-) on Sb release. PMID:26531710

  6. Development of a field worthy sensor system to monitor gaseous nitrogen transfer from agricultural cropland. Phase 1, Final report

    SciTech Connect

    Not Available

    1992-11-01

    Nitrogen fertilizer accounts for 25 to 33% of the energy requirements in modern crop agriculture in the world today. Energy input for the manufacture of these N fertilizers is in the range of 460 {times} 10{sup 12} Btu per year. Unfortunately, for some N sources up to 70% of this energy in the form of NK can be lost through improper application techniques and poor N management strategies. Anhydrous NH{sub 3} may be lost to the atmosphere during and after placement due to soil conditions placement. Measurement of volatile N is difficult, especially under field conditions. A precise and convenient method of measuring gaseous NH{sub 3} near and above the soil surface is prerequisite to the development and evaluation of altemative fertilizer management strategies and application techniques which can reduce the potential for significant loss. Recent advances in integrated-optic (IO) based sensing offers the potential of measuring low levels of NH{sub 3} loss from a cropping system in the range of 100 ppB. The integrated design of an IO system allows for a more durable device that can be mass produced at low cost. Under Phase I of this project, two IO devices were designed and tested: an absorption device using an oxazine dye as a waveguide coating and an interferometric device using an anilinium salt as a waveguide coating.

  7. A PILOT STUDY OF GLOBAL POSITION SYSTEM/GEOGRAPHICAL INFORMATION SYSTEM MEASUREMENT OF RESIDENTIAL PROXIMITY TO AGRICULTURE FIELDS AND URINARY ORGANOPHOSPHATE METABOLITE CONCENTRATIONS IN TODDLERS

    EPA Science Inventory

    A pilot study of global position system/geographical information system measurement of residential proximity to agricultural fields and urinary organophosphate metabolite concentrations in toddlers

    Michael O. Royster1, Elizabeth D. Hilborn1, Dana Barr2, Cara L. Carty1, Sco...

  8. Spatiotemporal characterization of soil moisture fields in agricultural areas using cosmic-ray neutron probes and data fusion

    NASA Astrophysics Data System (ADS)

    Franz, Trenton; Wang, Tiejun

    2015-04-01

    Approximately 40% of global food production comes from irrigated agriculture. With the increasing demand for food even greater pressures will be placed on water resources within these systems. In this work we aimed to characterize the spatial and temporal patterns of soil moisture at the field-scale (~500 m) using the newly developed cosmic-ray neutron rover near Waco, NE USA. Here we mapped soil moisture of 144 quarter section fields (a mix of maize, soybean, and natural areas) each week during the 2014 growing season (May to September). The 12 by 12 km study domain also contained three stationary cosmic-ray neutron probes for independent validation of the rover surveys. Basic statistical analysis of the domain indicated a strong relationship between the mean and variance of soil moisture at several averaging scales. The relationships between the mean and higher order moments were not significant. Scaling analysis indicated strong power law behavior between the variance of soil moisture and averaging area with minimal dependence of mean soil moisture on the slope of the power law function. In addition, we combined the data from the three stationary cosmic-ray neutron probes and mobile surveys using linear regression to derive a daily soil moisture product at 1, 3, and 12 km spatial resolutions for the entire growing season. The statistical relationships derived from the rover dataset offer a novel set of observations that will be useful in: 1) calibrating and validating land surface models, 2) calibrating and validating crop models, 3) soil moisture covariance estimates for statistical downscaling of remote sensing products such as SMOS and SMAP, and 4) provide daily center-pivot scale mean soil moisture data for optimal irrigation timing and volume amounts.

  9. Dry Deposition of Fine Aerosol Nitrogen to an Agricultural Field Measured by Eddy-Correlation Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Gonzales, D. A.; Allen, J. O.

    2005-12-01

    In urban areas high emissions of reactive nitrogen species cause an increase in atmospheric aerosol nitrogen formation and deposition. This nitrogen is eventually removed from the atmosphere by wet or dry deposition, with dry deposition often accounting for more than half of the total deposition of particulate nitrate. Total N deposition is not adequately characterized, in part because dry deposition is difficult to measure or model. For example measured fine particle deposition to a forest canopy differs from predicted values by an order of magnitude. The eddy-correlation technique is a micrometeorological method used to directly measure fluxes from measurements made above the surface. Eddy-correlation mass spectrometry (ECMS) has been developed to directly measure aerosol particle deposition velocities from fast response aerosol concentration and wind velocity measurements. Using an Aerodyne Aerosol Mass Spectrometer (AMS), the size and composition of ambient aerosols were measured at 10~Hz. The AMS signal is proportional to non-refractory PM1.0 mass. Aerosol deposition fluxes for a given averaging period are then calculated directly as the covariance of the vertical wind velocity with the AMS signal (F = -\\overline{w'S'}). A field study was conducted to measure aerosol nitrogen dry deposition to an agricultural field immediately downwind of the Phoenix metropolitan area using eddy-correlation mass spectrometry. The study was supplemented with aerosol composition measurements including bulk deposition collectors and filter bank samplers. Here we compare the results of the flux estimates from bulk collection with inferential measurements (filter samples and modeled deposition velocities) and direct micrometeorological measurements (ECMS) in order to improve nitrogen deposition estimates.

  10. Dry Deposition of Fine Aerosol Nitrogen to an Agricultural Field Measured by Eddy-Correlation Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Gonzales, D. A.; Allen, J. O.; Smith, K. A.; Hope, D.

    2004-12-01

    In urban areas high emissions of reactive nitrogen species cause an increase in atmospheric aerosol nitrogen formation and deposition. This nitrogen is eventually removed from the atmosphere by wet or dry deposition, with dry deposition often accounting for more than half of the total deposition of particulate nitrate (Lovett, 1994). Total N deposition is not adequately characterized, in part because dry deposition is difficult to measure or model. For example measured fine particle deposition to a forest canopy differs from predicted values by an order of magnitude (Gallagher et al., 1997). The eddy-correlation technique is a micrometeorological method used to directly measure fluxes from measurements made above the surface (Wesely and Hicks, 2000). Eddy-correlation mass spectrometry (ECMS) has been developed to directly measure aerosol particle deposition velocities from fast response aerosol concentration and wind velocity measurements. Using an Aerodyne Aerosol Mass Spectrometer (AMS) (Jayne et al., 2000), the size and composition of ambient aerosols is measured at a high frequency. The AMS signal is proportional to non-refractory PM1.0 mass. Aerosol deposition fluxes for a given averaging period are then calculated directly as the covariance of the vertical wind velocity with the AMS signal (F = -/line{w'S'}). A field study was conducted to measure aerosol nitrogen dry deposition to an agricultural field immediately downwind of the Phoenix metropolitan area using eddy-correlation mass spectrometry. The study was supplemented with aerosol composition measurements including bulk deposition collectors and filter bank samplers. Bulk deposition samples and 24-hour filter samples were analyzed for ammonia and nitrogen. Here we compare the results of the flux estimates from bulk collection with inferential measurements (filter samples and modeled deposition velocities) and direct micrometeorological measurements (ECMS) in order to improve N deposition estimates.

  11. Agriculture Education. Agriculture Structures.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary agricultural education students enrolled in one or two semester-long courses in agriculture structures. The guide presents units of study in the following areas: (1) shop safety, (2) identification and general use of hand tools, (3) power tools, (4) carpentry, (5) blueprint…

  12. Resilience at the Transition to Agriculture: The Long-Term Landscape and Resource Development at the Aceramic Neolithic Tell Site of Chogha Golan (Iran)

    PubMed Central

    Riehl, S.; Asouti, E.; Karakaya, D.; Starkovich, B. M.; Zeidi, M.; Conard, N. J.

    2015-01-01

    The evidence for the slow development from gathering and cultivation of wild species to the use of domesticates in the Near East, deriving from a number of Epipalaeolithic and aceramic Neolithic sites with short occupational stratigraphies, cannot explain the reasons for the protracted development of agriculture in the Fertile Crescent. The botanical and faunal remains from the long stratigraphic sequence of Chogha Golan, indicate local changes in environmental conditions and subsistence practices that characterize a site-specific pathway into emerging agriculture. Our multidisciplinary approach demonstrates a long-term subsistence strategy of several hundred years on wild cereals and pulses as well as on hunting a variety of faunal species that were based on relatively favorable and stable environmental conditions. Fluctuations in the availability of resources after around 10.200 cal BP may have been caused by small-scale climatic fluctuations. The temporary depletion of resources was managed through a shift to other species which required minor technological changes to make these resources accessible and by intensification of barley cultivation which approached its domestication. After roughly 200 years, emmer domestication is apparent, accompanied by higher contribution of cattle in the diet, suggesting long-term intensification of resource management. PMID:26345115

  13. Resilience at the Transition to Agriculture: The Long-Term Landscape and Resource Development at the Aceramic Neolithic Tell Site of Chogha Golan (Iran).

    PubMed

    Riehl, S; Asouti, E; Karakaya, D; Starkovich, B M; Zeidi, M; Conard, N J

    2015-01-01

    The evidence for the slow development from gathering and cultivation of wild species to the use of domesticates in the Near East, deriving from a number of Epipalaeolithic and aceramic Neolithic sites with short occupational stratigraphies, cannot explain the reasons for the protracted development of agriculture in the Fertile Crescent. The botanical and faunal remains from the long stratigraphic sequence of Chogha Golan, indicate local changes in environmental conditions and subsistence practices that characterize a site-specific pathway into emerging agriculture. Our multidisciplinary approach demonstrates a long-term subsistence strategy of several hundred years on wild cereals and pulses as well as on hunting a variety of faunal species that were based on relatively favorable and stable environmental conditions. Fluctuations in the availability of resources after around 10.200 cal BP may have been caused by small-scale climatic fluctuations. The temporary depletion of resources was managed through a shift to other species which required minor technological changes to make these resources accessible and by intensification of barley cultivation which approached its domestication. After roughly 200 years, emmer domestication is apparent, accompanied by higher contribution of cattle in the diet, suggesting long-term intensification of resource management. PMID:26345115

  14. Field screening at petroleum contaminated sites: A tool to save time, money

    SciTech Connect

    Hood, G.M.; Pucel, P.G.; Allee, P.

    1998-01-01

    The most expensive part of an environmental assessment is often lab services. Control of these costs while still collecting adequate data to assess a site is sometimes the difference between solvency and bankruptcy, especially for small companies. Fortunately, the use of field screening techniques can significantly reduce the quantity of samples going to the laboratory for analysis, thus controlling overall project costs. Chemical and Environmental Consultants, Inc. (CEC) has been field evaluating a rapid, widely applicable method for field screening petroleum contaminated soils and wastes for SVOCs. The method is similar in application to US EPA Method 418.1 and allows for the field screening of soil and waste samples in about 10 minutes. The method uses fluorescence spectroscopy analysis of a solvent extract of the soil or waste sample.

  15. Terrestrial field dissipation of diclosulam at four sites in the United States.

    PubMed

    Zabik, J M; van Wesenbeeck, I J; Peacock, A L; Kennard, L M; Roberts, D W

    2001-07-01

    The soil dissipation of diclosulam was studied using 14C-labeled and nonradiolabeled material in Mississippi, North Carolina, Georgia, and Illinois between 1994 and 1997. The test substance was preemergence broadcast applied at target rates of 35 and 37 g ai x ha(-1) for the 14C-labeled and the nonradiolabeled studies, respectively. The degradation of diclosulam was rapid with half-lives ranging from 13 to 43 days at the four sites. Rapid degradation rates and the increasing sorption to soil over time resulted in low persistence and mobility of this compound. Metabolite formation and dissipation in the field reflected observations of photolysis, hydrolysis, and aerobic soil metabolism studies in the laboratory. The rapid field dissipation rates, metabolite formation patterns, and sorption characteristics obtained in these field studies were consistent with the laboratory data generated for diclosulam, and reflect the multiple concurrent degradation mechanisms occurring in the field. PMID:11453764

  16. Microbial adaption to a pesticide in agricultural soils: Accelerated degradation of 14C-atrazine in field soils from Brazil and Belgium

    NASA Astrophysics Data System (ADS)

    Jablonowski, Nicolai David; Martinazzo, Rosane; Hamacher, Georg; Accinelli, Cesare; Köppchen, Stephan; Langen, Ulrike; Linden, Andreas; Krause, Martina; Burauel, Peter

    2010-05-01

    An increasing demand for food, feed and bioenergy, and simultaneously a decline of arable land will require an intensive agricultural production including the use of pesticides. With an increasing use of pesticides the occurrence of an accelerated degradation potential has to be assessed. Atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] is one of the most widely used herbicides in the world. Even though its use was banned in several countries it is still widely used throughout America and the Asia-Pacific region. Atrazine is the most widely used herbicide in maize plantations in Brazil and the US. The use of atrazine in Belgium and all EU member states was banned in September 2004, with the permission to consume existing stocks until October 2005. Atrazine and its residues are still regularly detected in soil, ground and surface waters even years after its prohibition. Its persistence in soil and in association with organic particles might become crucial in terms of erosion due to climate and environmental changes. Due to its potential microbiological accessibility, the microbial mineralization of atrazine competes with chemical/physical interaction such as sorption and binding processes of the chemical molecule in the soil matrix. Binding or intrusion of the chemical on soil components results in a decrease of its accessibility for soil microbes, which does not necessarily exclude the molecule from environmental interactions. In the present study the accelerated atrazine degradation in agriculturally used soils was examined. Soil samples were collected from a Rhodic Ferralsol, Campinas do Sul, South Brazil, and Geric Ferralsol, Correntina, Northeastern Brazil. The sampling site of the Rhodic Ferralsol soil has been under crop rotation (soybean/wheat/maize/oat) since 1990. The Geric Ferralsol site has alternately been cultivated with maize and soybean since 2000. Both areas have been treated biennially with atrazine at recommended doses of 1.5 - 3

  17. Field demonstration of remedial technologies at a former manufactured gas plant site

    SciTech Connect

    Moreau, J.P.

    1998-12-31

    From the mid 1800s until the late 1950s, the major energy source for domestic lighting, heating, and cooking was a manufactured fuel derived from the pyrolysis of coal and oil. These manufactured gas production facilities were located throughout the country; at one time more than 3000 plants may have been in operation, with 180 in New York state alone. During the 1950s, the installation of a vast interstate gas pipeline system allowed the transport of relatively inexpensive natural gas from oil production fields to the metropolitan areas. This natural gas had a BTU content of almost twice that of manufactured gas and, being inherently cheaper, resulted in the overnight demise of the MGP industry. The vast majority of the MGP facilities were demolished and the sites either converted to other uses or abandoned. In the early 1980s, utilities discovered these long abandoned production facilities during various environmental site assessments and audits. In 1990, NMPC initiated a project at a MGP byproduct disposal site (EPRI Site 24) to investigate the technologies necessary for removal of contaminated source materials and soils, treatment of the impacted soil, and evaluation of the potential for natural attenuation of a contaminated groundwater plume (EPRI, 1996). MGP-impacted soil from this site was transported to two treatment facilities: a cement Kiln in North Carolina, and an asphalt plant in Virginia. This experience generated considerable data on management of these sites, even though this site was a simple disposal area and not a former production facility. A long-term monitoring program is indicating that natural attenuation processes appear to b responsible for the decreasing levels of key constituents in the groundwater after source materials are removed. A number of key lessons learned were generated from the study, especially recognizing that transportation is a major cost component in site remediation.

  18. Use of field and airborne advanced remote sensing data for the characterisation of surface erosional stages in agricultural semi-arid soils (central Spain) at various scales

    NASA Astrophysics Data System (ADS)

    Milewski, Robert; Chabrillat, Sabine; Schmid, Thomas; Rodriguez, Manuel; Schuett, Brigitta

    2014-05-01

    derived mainly from tillage practices. The identification of these contrasting soil surface layers based on the optical properties of different soil components is a major goal of this study. The optical analysis is accompanied by a geomorphological assessment of the spatial distribution of defined soil erosion and depositional stages. Morphometric variables derived from a digital terrain model based on the acquired LIDAR data are related to topographical features and associated with local soil erosion models that exist for the study area. In this paper we present preliminary results at various scales from field and remote sensing analyses over selected test sites chosen as representative of the main soil types in the area, and of the main erosion and depositional stages that could be observed. Results show that the identification and mapping of different soil horizons linked to soil erosion and depositional stages as well as slope and curvature analyses can be achieved based on the spectroscopy data and on the LIDAR data, respectively. Therefore, the spatial mapping of the soil erosion and depositional stages are consistent with the soil erosion models implemented for southern agricultural areas.

  19. Impact assessment and recommendation of alternative conjunctive water use strategies for salt affected agricultural lands through a field scale decision support system - a case study.

    PubMed

    Kaur, Ravinder; Paul, Madhumita; Malik, Rashmi

    2007-06-01

    Conjunctive use of saline/non-saline irrigation waters is generally aimed at minimizing yield losses and enhancing flexibility of cropping, without much alteration in farming operations. Recommendation of location-specific suitable conjunctive water use plans requires assessment of their long-term impacts on soil salinization/sodification and crop yield reductions. This is conventionally achieved through long-term field experiments. However such impact evaluations are site specific, expensive and time consuming. Appropriate decision support systems (DSS) can be time-efficient and cost-effective means for such long-term impact evaluations. This study demonstrates the application of one such (indigenously developed) DSS for recommending best conjunctive water use plans for a, rice-wheat growing, salt affected farmer's field in Gurgaon district of Haryana (India). Before application, the DSS was extensively validated on several farmers and controlled experimental fields in Gurgaon and Karnal districts of Haryana (India). Validation of DSS showed its potential to give realistic estimates of root zone soil salinity (with R = 0.76-0.94; AMRE = 0.03-0.06; RMSPD = 0.51-0.90); sodicity (with R = 0.99; AMRE = 0.02; RMSPD = 0.84) and relative crop yield reductions (AMRE = 0.24), under existing (local) resource management practices. Long term (10 years) root zone salt build ups and associated rice/wheat crop yield reductions, in a salt affected farmer's field, under varied conjunctive water use scenarios were evaluated with the validated DSS. It was observed that long-term applications of canal (CW) and tube well (TW) waters in a cycle and in 1:1 mixed mode, during Kharif season, predicted higher average root zone salt reductions (2-9%) and lower rice crop yield reductions (4-5%) than the existing practice of 3-CW, 3-TW, 3-CW. Besides this, long-term application of 75% CW mixed with 25% TW, during Rabi season, predicted about 17% lower average root-zone salt reductions than

  20. Absence of the hyperfine magnetic field at the Ru site in ferromagnetic rare-earth intermetallics

    SciTech Connect

    Coffey, D.; DeMarco, M.; Ho, P. C.; Maple, M. B.; Sayles, T.; Lynn, J. W.; Huang, Q.; Toorongian, S.; Haka, M.

    2010-05-01

    The Moessbauer effect (ME) is frequently used to investigate magnetically ordered systems. One usually assumes that the magnetic order induces a hyperfine magnetic field, B{sub hyperfine}, at the ME active site. This is the case in the ruthenates, where the temperature dependence of B{sub hyperfine} at {sup 99}Ru sites tracks the temperature dependence of the ferromagnetic or antiferromagnetic order. However this does not happen in the rare-earth intermetallics, GdRu{sub 2} and HoRu{sub 2}. Specific heat, magnetization, magnetic susceptibility, Moessbauer effect, and neutron diffraction have been used to study the nature of the magnetic order in these materials. Both materials are found to order ferromagnetically at 83.1 and 15.3 K, respectively. Despite the ferromagnetic order of the rare-earth moments in both systems, there is no evidence of a correspondingly large B{sub hyperfine} in the Moessbauer spectrum at the Ru site. Instead the measured spectra consist of a narrow peak at all temperatures which points to the absence of magnetic order. To understand the surprising absence of a transferred hyperfine magnetic field, we carried out ab initio calculations which show that spin polarization is present only on the rare-earth site. The electron spin at the Ru sites is effectively unpolarized and, as a result, B{sub hyperfine} is very small at those sites. This occurs because the 4d Ru electrons form broad conduction bands rather than localized moments. These 4d conduction bands are polarized in the region of the Fermi energy and mediate the interaction between the localized rare-earth moments.

  1. Absence of the hyperfine magnetic field at the Ru site in ferromagnetic rare-earth intermetallics

    NASA Astrophysics Data System (ADS)

    Coffey, D.; Demarco, M.; Ho, P. C.; Maple, M. B.; Sayles, T.; Lynn, J. W.; Huang, Q.; Toorongian, S.; Haka, M.

    2010-05-01

    The Mössbauer effect (ME) is frequently used to investigate magnetically ordered systems. One usually assumes that the magnetic order induces a hyperfine magnetic field, Bhyperfine , at the ME active site. This is the case in the ruthenates, where the temperature dependence of Bhyperfine at R99u sites tracks the temperature dependence of the ferromagnetic or antiferromagnetic order. However this does not happen in the rare-earth intermetallics, GdRu2 and HoRu2 . Specific heat, magnetization, magnetic susceptibility, Mössbauer effect, and neutron diffraction have been used to study the nature of the magnetic order in these materials. Both materials are found to order ferromagnetically at 83.1 and 15.3 K, respectively. Despite the ferromagnetic order of the rare-earth moments in both systems, there is no evidence of a correspondingly large Bhyperfine in the Mössbauer spectrum at the Ru site. Instead the measured spectra consist of a narrow peak at all temperatures which points to the absence of magnetic order. To understand the surprising absence of a transferred hyperfine magnetic field, we carried out ab initio calculations which show that spin polarization is present only on the rare-earth site. The electron spin at the Ru sites is effectively unpolarized and, as a result, Bhyperfine is very small at those sites. This occurs because the 4d Ru electrons form broad conduction bands rather than localized moments. These 4d conduction bands are polarized in the region of the Fermi energy and mediate the interaction between the localized rare-earth moments.

  2. Thresholds of arsenic toxicity to Eisenia fetida in field-collected agricultural soils exposed to copper mining activities in Chile.

    PubMed

    Bustos, Víctor; Mondaca, Pedro; Verdejo, José; Sauvé, Sébastien; Gaete, Hernán; Celis-Diez, Juan L; Neaman, Alexander

    2015-12-01

    Several previous studies highlighted the importance of using field-collected soils-and not artificially-contaminated soils-for ecotoxicity tests. However, the use of field-collected soils presents several difficulties for interpretation of results, due to the presence of various contaminants and unavoidable differences in the physicochemical properties of the tested soils. The objective of this study was to estimate thresholds of metal toxicity in topsoils of 24 agricultural areas historically contaminated by mining activities in Chile. We performed standardized earthworm reproduction tests (OECD 222 and ISO 11268-2) with Eisenia fetida. Total soil concentrations of Cu, As, Zn, and Pb were in the ranges of 82-1295 mg kg(-1), 7-41 mg kg(-1), 86-345 mg kg(-1), and 25-97 mg kg(-1), respectively. In order to differentiate between the effects of different metals, we used regression analysis between soil metal concentrations and earthworm responses, as well as between metal concentrations in earthworm tissues and earthworm responses. Based on regression analysis, we concluded that As was a metal of prime concern for Eisenia fetida in soils affected by Cu mining activities, while Cu exhibited a secondary effect. In contrast, the effects of Zn and Pb were not significant. Soil electrical conductivity was another significant contributor to reproduction toxicity in the studied soils, forcing its integration in the interpretation of the results. By using soils with electrical conductivity ≤ 0.29 dS m(-1) (which corresponds to EC50 of salt toxicity to Eisenia fetida), it was possible to isolate the effect of soil salinity on earthworm reproduction. Despite the confounding effects of Cu, it was possible to determine EC10, EC25 and EC50 values for total soil As at 8 mg kg(-1), 14 mg kg(-1) and 22 mg kg(-1), respectively, for the response of the cocoon production. However, it was not possible to determine these threshold values for juvenile production. Likewise, we were able to

  3. Expected near-field thermal performance for nuclear waste repositories at potential salt sites: Technical report

    SciTech Connect

    McNulty, E.G.

    1987-08-01

    Thermal analyses were made for the environmental assessments of seven potential salt sites for a nuclear waste repository. These analyses predicted that potential repository sites in domal salts located in the Gulf Coast will experience higher temperature than those in bedded salts of Paradox and Palo Duro Basins, mainly because of higher ambient temperatures at depth. The TEMPV5 code, a semi-analytical heat transfer code for finite line sources, calculated temperatures for commercial high-level waste (CHLW) and spent fuel from pressurized-water reactors (SFPWR). Benchmarks with HEATING6, THAC-SIP-3D, STEALTH, and SPECTROM-41 showed that TEMPV5 agreed closely in the very near field around the waste package and approximately in the near-field and far-field regions of the repository. The analyses used site-specific thermal conductivities that were increased by 40% to compensate for reductions caused by testing technique, salt impurities, and other heterogeneities, and sampling disturbance. Analyses showed peak salt temperatures of 236/sup 0/C (CHLW) and 134/sup 0/C (SFPWR) for the bedded salt and 296/sup 0/C (CHLW) and 180/sup 0/C (SFPWR) for the domal salt. Analyses with uncorrected laboratory thermal conductivities would increase peak salt temperatures by about 120/sup 0/C for CHLW and about 60/sup 0/C for SFPWR. These temperature increases would increase the thermally induced flow of brine and accelerate corrosion of the waste package. 30 refs., 35 figs., 48 tabs.

  4. Field Summary Report for Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington, Collection of Surface Water, River Sediments, and Island Soils

    SciTech Connect

    L. C. Hulstrom

    2009-09-28

    This report has been prepared in support of the remedial investigation of Hanford Site Releases to the Columbia River and describes the 2008/2009 data collection efforts. This report documents field activities associated with collection of sediment, river water, and soil in and adjacent to the Columbia River near the Hanford Site and in nearby tributaries.

  5. Field populations of native Indian honey bees from pesticide intensive agricultural landscape show signs of impaired olfaction

    PubMed Central

    Chakrabarti, Priyadarshini; Rana, Santanu; Bandopadhyay, Sreejata; Naik, Dattatraya G.; Sarkar, Sagartirtha; Basu, Parthiba

    2015-01-01

    Little information is available regarding the adverse effects of pesticides on natural honey bee populations. This study highlights the detrimental effects of pesticides on honey bee olfaction through behavioural studies, scanning electron microscopic imaging of antennal sensillae and confocal microscopic studies of honey bee brains for calcium ions on Apis cerana, a native Indian honey bee species. There was a significant decrease in proboscis extension response and biologically active free calcium ions and adverse changes in antennal sensillae in pesticide exposed field honey bee populations compared to morphometrically similar honey bees sampled from low/no pesticide sites. Controlled laboratory experiments corroborated these findings. This study reports for the first time the changes in antennal sensillae, expression of Calpain 1(an important calcium binding protein) and resting state free calcium in brains of honey bees exposed to pesticide stress. PMID:26212690

  6. Field populations of native Indian honey bees from pesticide intensive agricultural landscape show signs of impaired olfaction

    NASA Astrophysics Data System (ADS)

    Chakrabarti, Priyadarshini; Rana, Santanu; Bandopadhyay, Sreejata; Naik, Dattatraya G.; Sarkar, Sagartirtha; Basu, Parthiba

    2015-07-01

    Little information is available regarding the adverse effects of pesticides on natural honey bee populations. This study highlights the detrimental effects of pesticides on honey bee olfaction through behavioural studies, scanning electron microscopic imaging of antennal sensillae and confocal microscopic studies of honey bee brains for calcium ions on Apis cerana, a native Indian honey bee species. There was a significant decrease in proboscis extension response and biologically active free calcium ions and adverse changes in antennal sensillae in pesticide exposed field honey bee populations compared to morphometrically similar honey bees sampled from low/no pesticide sites. Controlled laboratory experiments corroborated these findings. This study reports for the first time the changes in antennal sensillae, expression of Calpain 1(an important calcium binding protein) and resting state free calcium in brains of honey bees exposed to pesticide stress.

  7. A novel genome-wide polyadenylation sites recognition system based on condition random field.

    PubMed

    Han, Jiuqiang; Zhang, Shanxin; Liu, Jun; Liu, Ruiling

    2014-01-01

    Polyadenylation including the cleavage of pre-mRNA and addition of a stretch of adenosines to the 3'-end is an essential step of pre-mRNA processing in eukayotes. The known regulatory role of polyadenylation in mRNA localization, stability, and translation and the emerging link between poly(A) and disease states underline the necessary to fully characterize polyadenylation sites. Several artificial intelligence methods have been proposed for poly(A) sites recognition. However, these methods are suitable to small subsets of genome sequences. It is necessary to propose a method for genome-wide recognition of poly(A) sites. Recent efforts have found a lot of poly(A) related factors on DNA level. Here, we proposed a novel genome-wide poly(A) recognition method based on the Condition Random Field (CRF) by integrating multiple features. Compared with the polya_svm (the most accurate program for prediction of poly(A) sites till date), our method had a higher performance with the area under ROC curve(0.8621 versus 0.6796). The result suggests that our method is an effective method in genome wide poly(A) sites recognition. PMID:25571055

  8. A Guide to Field Trip Sites in Coastal North Carolina. Project CAPE Teaching Module SC3a.

    ERIC Educational Resources Information Center

    Carroll, Walter B.; Carroll, Carolyn H.

    This guide provides information on preparing students in grades 4-10 for field trips and describes possible field trip sites in the northeastern, mid-eastern, and southeastern regions of North Carolina. Selected sites in the northeastern region (from Roanoke Island to Ocracoke) include the Dare Coastline and Cape Hatteras National Seashore.…

  9. Short-term temporal and spatial variability of soil hydrophobicity in an abandoned agriculture field in Lithuania

    NASA Astrophysics Data System (ADS)

    Pereira, Paulo; Burguet, Maria; Cerdà, Artemi

    2013-04-01

    Soil water repellency (SWR) is a natural property of soils. Among other factors, SWR depends on soil moisture, mineralogy, texture, pH, organic matter, aggregate stability, fungal and microbiological activity and plant cover. It has implications on plant growth, superficial and subsurface hydrology and soil erosion. It is well known that SWR is temporarily, increasing when soils are dry and decreasing when moist. In agriculture, soil micro-topography is very heterogeneous with implications on surface water distribution and wettability. Normally, SWR studies are focused on large interval time (e.g, monthly or seasonally). The objective of this work is the study of SWR in a temporal scale and its variability in an abandoned agriculture field in Lithuania. An experimental plot with 21 m2 (07x03 m) was designed in a flat area. Inside this plot SWR was measured in the field, placing three droplets of water on the soil surface and counting the time that takes to infiltrate. A total of 105 sampling points were measured per sampling period. Soil water repellency was measured after a period of 14 days without rainfall and in the seven consequent weeks (one measurement per week between 28th May and 07th of July 2012). The results showed that in this small plot, SWR was observed in the first (May 28), third and fourth measurements (08th of June and 16th). It was observed an increasing of the percentage of hydrophobic points (Water Drop Penetration Test ≥5 seconds) between the first and the fourth measurement, decreasing thereafter. Significant differences of SWR were observed among all periods (F=78.32, p<0.0001). The coefficient of variation (CV%) changed strikingly, 361.10 % (8th of May), 151.78 % (01st of June), 83.77% (08th of June), 125.87% (16th of June), 0.45 (22nd of June), 121%(31st of June) and 67.13% (7th of July). The correlation between the mean SWR and the CV% is 0.75, p<0.05. The changes were attributed to different soil moisture conditions. The differences

  10. Sample Characterization of FIDO-2000 and FIDO-2002 Blind Field Test Sites by an APXS Instrument

    NASA Astrophysics Data System (ADS)

    Economou, T. E.

    2002-12-01

    The Mars Rover Explorer (MER) Project conducted in the past few years two major blind field test that involved the Field Integrated Design and Operations (FIDO) rover, with a payload not quite, but close to the real MER mission flight payload. Since the APXS and the MB spectrometer cannot operate properly in the Earth's atmosphere, a representative variety of rocks and soil samples from designated "landing" sites were collected and sent to the respective laboratories for analyses with these two instruments. During the field tests, the data from FIDO instruments, together with the appropriate data from the APXS and MB spectrometers, which, according to the site operators opinion, most closely resembled the real analyzed samples, were transmitted to the control room at JPL for target evaluation. The APXS analyzed both, the natural side and the fresh cut side, of most of the rocks that were made available. By comparing the analytical results from both sides, it was possible to clearly detect and evaluate alteration rinds and coatings on the analyzed rocks. Desert varnish, thin iron and carbon coatings were found on natural side of some rocks, but not others. The elemental composition results by the APXS contributed synergistically with the other FIDO instruments to derive the mineralogical and geological characterization of the sites by imposing limits on the amounts and the variety of specific minerals. Most of the analyzed samples from both FIDO field test sites were very high in silica and alumina. In a few cases, the analyses were compatible with pure quartz. The alpha mode of the APXS is especially valuable for detecting even small amounts of carbonates. In many instances, it was possible to show that the carbon was only on the surface of some rocks. Examples of the APXS results from both blind field tests will be presented and discussed at the meeting The APXS results will be compared to the Pathfinder APXS rock analyses and conclusions will be made about rinds

  11. Secondary organic aerosol characterization at field sites across the United States during the spring-summer period

    EPA Science Inventory

    Sources of secondary organic carbon at 15 field sites across the United States (U.S.) during the years 2003-2010 have been examined. Filter samples have been taken for 24-h at a site in Research Triangle Park, NC; at SEARCH sites in southeastern U.S. during May and August 2005; ...

  12. Runoff of pharmaceuticals and personal care products following application of dewatered municipal biosolids to an agricultural field.

    PubMed

    Sabourin, Lyne; Beck, Andrew; Duenk, Peter W; Kleywegt, Sonya; Lapen, David R; Li, Hongxia; Metcalfe, Chris D; Payne, Michael; Topp, Edward

    2009-08-01

    Municipal biosolids are a useful source of nutrients for crop production, and commonly used in agriculture. In this field study, we applied dewatered municipal biosolids at a commercial rate using broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 21 and 34 days following the application on 2 m(2) microplots to evaluate surface runoff of various pharmaceuticals and personal care products (PPCPs), namely atenolol, carbamazepine, cotinine, caffeine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole, triclosan and triclocarban. There was little temporal coherence in the detection of PPCPs in runoff, various compounds being detected maximally on days 1, 3, 7 or 36. Maximum concentrations in runoff ranged from below detection limit (gemfibrozil) to 109.7 ng L(-1) (triclosan). Expressing the total mass exported as a percentage of that applied, some analytes revealed little transport potential (<1% exported; triclocarban, triclosan, sulfamethoxazole, ibuprofen, naproxen and gemfibrozil) whereas others were readily exported (>1% exported; acetaminophen, carbamazepine, caffeine, cotinine, atenolol). Those compounds with little transport potential had log K(ow) values of 3.18 or greater, whereas those that were readily mobilized had K(ow) values of 2.45 or less. Maximal concentrations of all analytes were below toxic concentrations using a variety of endpoints available in the literature. In summary, this study has quantified the transport potential in surface runoff of PPCPs from land receiving biosolids, identified that log K(ow) may be a determinant of runoff transport potential of these analytes, and found maximal concentrations of all chemicals tested to be below toxic concentrations using a variety of endpoints. PMID:19464726

  13. Analysis of field size distributions, LACIE test sites 5029, 5033, and 5039, Anhwei Province, People's Republic of China

    NASA Technical Reports Server (NTRS)

    Podwysocki, M. H.

    1976-01-01

    A study was made of the field size distributions for LACIE test sites 5029, 5033, and 5039, People's Republic of China. Field lengths and widths were measured from LANDSAT imagery, and field area was statistically modeled. Field size parameters have log-normal or Poisson frequency distributions. These were normalized to the Gaussian distribution and theoretical population curves were made. When compared to fields in other areas of the same country measured in the previous study, field lengths and widths in the three LACIE test sites were 2 to 3 times smaller and areas were smaller by an order of magnitude.

  14. SUMMARY OF TECHNIQUES AND UNIQUE USES FOR DIRECT PUSH METHODS IN SITE CHARACTERIZATION ON CONTAMINATED FIELD SITES

    EPA Science Inventory

    Site characterization of subsurface contaminant transport is often hampered by a lack of knowledge of site heterogeneity and temporal variations in hydrogeochemistry. Two case studies are reviewed to illustrate the utility of macro-scale mapping information along with spatially-...

  15. Intermittent spring flooding of agricultural fields will increase net global-warming potential of greenhouse gas fluxes

    NASA Astrophysics Data System (ADS)

    Paul, R. F.; Smyth, E. M.; Smith, C. M.; Kantola, I. B.; Krichels, A.; Yang, W. H.; DeLucia, E. H.

    2014-12-01

    The U.S. Corn Belt is currently a net source of carbon dioxide and nitrous dioxide to the atmosphere but is also a weak sink for methane. Climate change is projected to increase the frequency and duration of spring precipitation in the North American Midwest, resulting in intermittent flooding and ponding in agricultural fields. Inundation changes the greenhouse gas (GHG) fluxes of the soil, especially by promoting methanogenesis under anoxic conditions. DNA and 16S cDNA sequencing results of earlier, similar experiments confirmed the presence of methanogens in soil samples, albeit in low abundance (representing <0.01% of reads per sample). We installed collars into bare ground of a central Illinois research field to experiment with flooding conditions and observe changes in gas fluxes, microbial community, and soil chemistry. We established three treatments of five replicates—control, continuously flooded, and intermittently flooded—each with separate collars for gas flux measurements, soil sample collection, and soil probe measurements. A drip irrigation system flooded the headspaces of the collars to produce flooding events. The continuously flooded collars were maintained in a flooded condition for the duration of the experiment, and the intermittently flooded collars were flooded for 72 hours per flooding event and then kept dry for at least 5 days before the next flooding event. We measured net concentrations of N2O, CH4, and CO2 in situ using a static chamber connected to a cavity ringdown spectrometer. We found that the periodicity of wetting and drying events induces hysteresis effects that push GHG shifts to occur rapidly (< 1 hr). Integrating fluxes across the period of the experiment, the intermittently flooded collars showed 88.7% higher global-warming potential of GHG fluxes at the 100-year horizon versus control, with most of change driven by increased net CO2 flux (87.1% higher) and net methane flux (29 times higher). These data indicate that

  16. Vertical Chlorophyll Canopy Structure Affects the Remote Sensing Based Predictability of LAI, Chlorophyll and Leaf Nitrogen in Agricultural Fields

    NASA Astrophysics Data System (ADS)

    Boegh, E.; Houborg, R.; Bienkowski, J.; Braban, C. F.; Dalgaard, T.; van Dijk, N.; Dragosits, U.; Holmes, E.; Magliulo, V.; Schelde, K.; Di Tommasi, P.; Vitale, L.; Theobald, M.; Cellier, P.; Sutton, M.

    2012-12-01

    Leaf nitrogen and leaf surface area influence the exchange of gases between terrestrial ecosystems and the atmosphere, and they play a significant role in the global cycles of carbon, nitrogen and water. Remote sensing can be used to estimate leaf area index (LAI), chlorophyll content (CHL) and leaf nitrogen (N), but methods are often developed using plot-scale data and not verified over extended regions characterized by variations in environmental boundary conditions (soil, atmosphere) and canopy structures. Estimation of N can be indirect due to its association with CHL, however N is also included in pigments such as carotenoids and anthocyanin which have different spectral signatures than CHL. Photosynthesis optimization theory suggests that plants will distribute their N resources in proportion to the light gradient within the canopy. Such vertical variation in CHL and N complicates the evaluation of remote sensing-based methods. Typically remote sensing studies measure CHL of the upper leaf, which is then multiplied by the green LAI to represent canopy chlorophyll content, or random sampling is used. In this study, field measurements and high spatial resolution (10-20 m) remote sensing images acquired from the HRG and HRVIR sensors aboard the SPOT satellites were used to assess the predictability of LAI, CHL and N in five European agricultural landscapes located in Denmark, Scotland (United Kingdom), Poland, The Netherlands and Italy . All satellite images were atmospherically using the 6SV1 model with atmospheric inputs estimated by MODIS and AIRS data. Five spectral vegetation indices (SVIs) were calculated (the Normalized Difference Vegetation index, the Simple Ratio, the Enhanced Vegetation Index-2, the Green Normalized Difference Vegetation Index, and the green Chlorophyll Index), and an image-based inverse canopy radiative transfer modelling system, REGFLEC (REGularized canopy reFLECtance) was applied to each of the five European landscapes. While the

  17. Genetic variability of spined soldier bugs (Hemiptera: Pentatomidae) sampled from distinct field sites and laboratory colonies in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spined soldier bug, Podisus maculiventris (Say), is an important biological control agent for agricultural and forest pests that preys on eggs and larvae of lepidopteran and coleopteran species. Genetic variability among field collected samples from Michigan, Mississippi, Missouri, and Florida, ...

  18. GROUND BEETLE OCCURRENCE IN ROTATED FIELDS OF BT CORN AND SOYBEAN IN THE SOUTH DAKOTA CORN ROOTWORM AREAWIDE SITE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ground beetles are important generalist predators in agricultural landscapes. During 2000-2001 we placed 2 transects of pitfall traps in each of 4 fields of rotated lepidopteran Bt corn and soybean. Sampling was conducted on a weekly basis and traps remained open for a 2-day period. In 2000, we c...

  19. Using remote sensing to characterize the influence of field-scale heterogeneity on in-site measurements of evapotranspiration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate estimates of field-scale evapotranspiration (ET) are critical to maximizing the efficient use of water for agricultural production which, particularly in arid and semi-arid environments, is the largest consumptive user of fresh water. Often, these estimates are derived using numerical or re...

  20. Post Audit of a Field Scale Reactive Transport Model of Uranium at a Former Mill Site

    NASA Astrophysics Data System (ADS)

    Curtis, G. P.

    2015-12-01

    Reactive transport of hexavalent uranium (U(VI)) in a shallow alluvial aquifer at a former uranium mill tailings site near Naturita CO has been monitored for nearly 30 years by the US Department of Energy and the US Geological Survey. Groundwater at the site has high concentrations of chloride, alkalinity and U(VI) as a owing to ore processing at the site from 1941 to 1974. We previously calibrated a multicomponent reactive transport model to data collected at the site from 1986 to 2001. A two dimensional nonreactive transport model used a uniform hydraulic conductivity which was estimated from observed chloride concentrations and tritium helium age dates. A reactive transport model for the 2km long site was developed by including an equilibrium U(VI) surface complexation model calibrated to laboratory data and calcite equilibrium. The calibrated model reproduced both nonreactive tracers as well as the observed U(VI), pH and alkalinity. Forward simulations for the period 2002-2015 conducted with the calibrated model predict significantly faster natural attenuation of U(VI) concentrations than has been observed by the persistent high U(VI) concentrations at the site. Alternative modeling approaches are being evaluating evaluated using recent data to determine if the persistence can be explained by multirate mass transfer models developed from experimental observations at the column scale(~0.2m), the laboratory tank scale (~2m), the field tracer test scale (~1-4m) or geophysical observation scale (~1-5m). Results of this comparison should provide insight into the persistence of U(VI) plumes and improved management options.

  1. Sustainable corn stover harvest strategies for Midwest agricultural landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To support emerging U.S. cellulosic bioenergy industries, 239 site-years of data from field studies at 36 sites in seven states were recently summarized in BioEnergy Research by the ARS Resilient Economic Agricultural Practices (REAP) team [formerly the Renewable Energy Assessment Project (REAP) tea...

  2. Agricultural land use and human presence around breeding sites increase stress-hormone levels and decrease body mass in barn owl nestlings.

    PubMed

    Almasi, Bettina; Béziers, Paul; Roulin, Alexandre; Jenni, Lukas

    2015-09-01

    Human activities can have a suite of positive and negative effects on animals and thus can affect various life history parameters. Human presence and agricultural practice can be perceived as stressors to which animals react with the secretion of glucocorticoids. The acute short-term secretion of glucocorticoids is considered beneficial and helps an animal to redirect energy and behaviour to cope with a critical situation. However, a long-term increase of glucocorticoids can impair e.g. growth and immune functions. We investigated how nestling barn owls (Tyto alba) are affected by the surrounding landscape and by human activities around their nest sites. We studied these effects on two response levels: (a) the physiological level of the hypothalamus-pituitary-adrenal axis, represented by baseline concentrations of corticosterone and the concentration attained by a standardized stressor; (b) fitness parameters: growth of the nestlings and breeding performance. Nestlings growing up in intensively cultivated areas showed increased baseline corticosterone levels late in the season and had an increased corticosterone release after a stressful event, while their body mass was decreased. Nestlings experiencing frequent anthropogenic disturbance had elevated baseline corticosterone levels, an increased corticosterone stress response and a lower body mass. Finally, breeding performance was better in structurally more diverse landscapes. In conclusion, anthropogenic disturbance affects offspring quality rather than quantity, whereas agricultural practices affect both life history traits. PMID:25903390

  3. Combined remediation technologies: results from field trials at chlorinated solvent impacted sites

    NASA Astrophysics Data System (ADS)

    O'Carroll, D. M.; Chowdhury, A. I.; Lomheim, L.; Boparai, H. K.; Weber, K.; Austrins, L. M.; Edwards, E.; Sleep, B.; de Boer, C. V.; Garcia, A. N.

    2015-12-01

    Non-aqueous phase liquids (NAPLs) are one class of waste liquids often generated from waste mixtures in industrial processes containing surfactants, chlorinated hydrocarbons and other compounds. Chlorinated solvents, a particularly persistent NAPL contaminant, frequently contaminate water sources for decades and are one of the more common contaminants at brownfield and industrialized sites. Although considerable advances in our understanding of the phenomena governing NAPL remediation have been made, and a number of innovative remediation technologies have been developed, existing technologies are rarely able to achieve clean up goals in contaminated aquifers at the completion of remedial activities. The development and pilot scale testing of new and innovative remediation technologies is, therefore, crucial to achieve clean up goals at contaminated sites. Our research group is currently investigating a number of innovative remediation technologies, either individually or as combined remedies. This includes the applicability of nanometals and ISCO (e.g., persulfate) for contaminated site remediation. These technologies can be combined with technologies to enhance amendment delivery (e.g., electrokinetics) or create conditions favorable for enhanced biotic contaminant degradation. This presentation will discuss outcomes from a number of field trials conducted at chlorinated solvent impacted sites by our group with a particular focus on combined remediation technologies.

  4. Evaluating three trace metal contaminated sites: a field and laboratory investigation.

    PubMed

    Murray, P; Ge, Y; Hendershot, W H

    2000-01-01

    Selecting guidelines to evaluate elevated metals in urban brownfields is hindered by the lack of information for these sites on ecosystem structure and function. A study was performed to compare three trace metal-contaminated sites in the metropolitan Montreal area. The goal was to obtain an idea of the organisms that may be present on urban brownfields and to measure if elevated metals alter the presence and activity of the indigenous biota. Field and laboratory studies were conducted using simple methodologies to determine the extent to which microbial activity affected by trace metal content, to assess diversity of plant and soil invertebrate communities and to measure phytoaccumulation of trace metals. It was found that microbial activity, as measured by substrate-induced respiration (SIR) and nitrification, was not affected by the levels of soil Cd, Cu, Ni, Pb and Zn recorded on the sites. Seven of the 12 invertebrate groups collected were sampled on soils with similar Cd, Cu, Ni, Pb and Zn concentrations. Diversity of plant species increased as a function of the length of time the sites had been inactive. Levels of metals in plant tissue were influenced by soil characteristics and not by total soil Cd, Cu, Ni, Pb and Zn. PMID:15093016

  5. Problems getting from the laboratory to the field: Reclamation of an AML site

    SciTech Connect

    Dick, W.A.; Stehouwer, R.C.; Bigham, J.M.; Beeghly, J.H.

    1994-12-31

    Acid and toxic abandoned mineland sites provide an opportunity whereby flue gas desulfurization (FGD) by-product can be beneficially used as a reclamation amendment material. Studies are needed to compare the effectiveness of FGD by-product, as compared with resoil, for reclamation purposes. Initial studies provided information about the chemical and physical properties of the FGD by-product and how to transport and blend the FGD by-product with yard waste compost. Greenhouse studies indicated that rates of 125 dry tons/acre of FGD and 50 dry tons/acre of yard waste compost would provide optimum results for reclamation of acid and toxic spoil contained at the Fleming abandoned mineland (AML) site. Their results showed that heavy metal loading rates were much lower using the FGD/compost mixture than using resoil material. Dioxin in the mixture was also less than the 5 ppt level considered as normal background. The technical problems of using FGD by-product for reclamation of an AML site were solved. However, considerable efforts to educate the public about the merits of reclaiming the Fleming AML site using this FGD/compost mixture were required before initiating field reclamation activities. Education efforts must continue if FGD by-products are to achieve general acceptance as a reclamation alternative to resoil in cases where resoil is of scarce supply.

  6. Criteria for Identifying and Evaluating Candidate Sites for Open-Field Trials of Genetically Engineered Mosquitoes

    PubMed Central

    Brown, David M.; Alphey, Luke S.; McKemey, Andrew; Beech, Camilla

    2014-01-01

    Abstract Recent laboratory successes in the development of genetically engineered mosquitoes for controlling pathogen transmission have fostered the need for standardized procedures for advancing the technical achievements to practical tools. It is incumbent in many cases for the same scientists doing the in-laboratory discovery research to also take on the initial challenges of developing the pathway that will move the technologies to the field. One of these challenges is having a set of criteria for selecting collaborators and sites for efficacy and safety field trials that combine rigorous science with good ethical and legal practices. Specific site-selection criteria were developed in four categories—Scientific, Regulatory, Community Engagement, and Resources—in anticipation of open-field releases of a transgenic mosquito strain designed to suppress populations of the dengue vector mosquito, Aedes aegypti. The criteria are derived from previous published material, discussions, and personal experiences with the expectation of providing guidance to laboratory scientists for addressing the conceptual and operational considerations for identifying partner researchers and countries with whom to collaborate. These criteria are not intended to be prescriptive nor can they be applied to every circumstance where genetic approaches are proposed for deployment. However, we encourage those involved in the discovery phase of research to consider each criterion during project planning activities, and where appropriate, incorporate them into a “go/no-go” decision-making process for further development and testing of the technologies. PMID:24689963

  7. Criteria for identifying and evaluating candidate sites for open-field trials of genetically engineered mosquitoes.

    PubMed

    Brown, David M; Alphey, Luke S; McKemey, Andrew; Beech, Camilla; James, Anthony A

    2014-04-01

    Recent laboratory successes in the development of genetically engineered mosquitoes for controlling pathogen transmission have fostered the need for standardized procedures for advancing the technical achievements to practical tools. It is incumbent in many cases for the same scientists doing the in-laboratory discovery research to also take on the initial challenges of developing the pathway that will move the technologies to the field. One of these challenges is having a set of criteria for selecting collaborators and sites for efficacy and safety field trials that combine rigorous science with good ethical and legal practices. Specific site-selection criteria were developed in four categories-Scientific, Regulatory, Community Engagement, and Resources-in anticipation of open-field releases of a transgenic mosquito strain designed to suppress populations of the dengue vector mosquito, Aedes aegypti. The criteria are derived from previous published material, discussions, and personal experiences with the expectation of providing guidance to laboratory scientists for addressing the conceptual and operational considerations for identifying partner researchers and countries with whom to collaborate. These criteria are not intended to be prescriptive nor can they be applied to every circumstance where genetic approaches are proposed for deployment. However, we encourage those involved in the discovery phase of research to consider each criterion during project planning activities, and where appropriate, incorporate them into a "go/no-go" decision-making process for further development and testing of the technologies. PMID:24689963

  8. The Field Lysimeter Test Facility (FLTF) at the Hanford Site: Installation and initial tests

    SciTech Connect

    Gee, G.W.; Kirkham, R.R.; Downs, J.L.; Campbell, M.D.

    1989-02-01

    The objectives of this program are to test barrier design concepts and to demonstrate a barrier design that meets established performance criteria for use in isolating wastes disposed of near-surface at the Hanford Site. Specifically, the program is designed to assess how well the barriers perform in controlling biointrusion, water infiltration, and erosion, as well as evaluating interactions between environmental variables and design factors of the barriers. To assess barrier performance and design with respect to infiltration control, field lysimeters and small- and large-scale field plots are planned to test the performance of specific barrier designs under actual and modified (enhanced precipitation) climatic conditions. The Field Lysimeter Test Facility (FLTF) is located in the 600 Area of the Hanford Site just east of the 200 West Area and adjacent to the Hanford Meteorological Station. The FLTF data will be used to assess the effectiveness of selected protective barrier configurations in controlling water infiltration. The facility consists of 14 drainage lysimeters (2 m dia x 3 m deep) and four precision weighing lysimeters (1.5 m x 1.5 m x 1.7 m deep). The lysimeters are buried at grade and aligned in a parallel configuration, with nine lysimeters on each side of an underground instrument chamber. The lysimeters were filled with materials to simulate a multilayer protective barrier system. Data gathered from the FLTF will be used to compare key barrier components and to calibrate and test models for predicting long-term barrier performance.

  9. Field Sampling Plan for the Distler Brickyard Superfund Site, Hardin County, Kentucky

    SciTech Connect

    J. P. Martin; L. N. Peterson; C. J. Taylor

    1999-08-01

    This plan describes the field and analytical activities to be conducted at the Distler Brickyard Superfund Site, Hardin County, Kentucky, in order to evaluate natural attenuation processes within the aquifer system. Sampling will consist of a single round to take place in October 1999. Analytes will consist of the contaminants of concern (chlorinated aliphatic hydrocarbons), electron donors (non-chlorinated organic compounds), oxidation-reduction indicators, and water quality parameters. These activities are conducted in order to evaluate the water quality parameters. These activities are conducted in order to evaluate the extent to which natural attenuation processes, in the form of anaerobic reductive dechlorination, may be taking place in the aquifer system. These data will then be used to select the appropriate remediation technology for this site.

  10. Comparison of Caprock Mineral Characteristics at Field Demonstration Sites for Saline Aquifer Sequestration of Carbon Dioxide

    SciTech Connect

    Griffith, C.A.; Lowry, G.; Dzombak, D.; Soong, Yee; Hedges, S.W.

    2008-10-01

    In 2003 the U.S Department of Energy initiated regional partnership programs to address the concern for rising atmospheric CO2. These partnerships were formed to explore regional and economical means for geologically sequestering CO2 across the United States and to set the stage for future commercial applications. Several options exist for geological sequestration and among these sequestering CO2 into deep saline aquifers is one of the most promising. This is due, in part, to the possibility of stabilized permanent storage through mineral precipitation from chemical interactions of the injected carbon dioxide with the brine and reservoir rock. There are nine field demonstration sites for saline sequestration among the regional partnerships in Phase II development to validate the overall commercial feasibility for CO2 geological sequestration. Of the nine sites considered for Phase II saline sequestration demonstration, seven are profiled in this study for their caprock lithologic and mineral characteristics.

  11. Field examination of ground water quality as an indicator of microbiological activity at gasoline contaminated sites.

    PubMed

    Norkus, R G; Maurer, J; Schultz, N A; Stuart, J D; Robbins, G A; Bristol, R D

    1996-08-01

    Various portable electrodes and an on-line colorimetric test kit were used in the field to examine ground water quality as an indicator of natural bioremediation across two sites in Connecticut having subsurface gasoline contamination. The parameters examined included dissolved oxygen, dissolved carbon dioxide, direct redox potential (Eh), nitrate, ammonia and pH. These parameters permitted delineating regions of aerobic and anaerobic microbiological activity. Variations in these parameters over an eighteen month period along with gas chromatographic analyses of certain gasoline components in the ground water indicated that in-situ bioremediation was effective at containing the petroleum contamination at both sites. It was found that a new on-line colorimetric test kit for the determination of oxygen was more accurate than a commonly used dissolved oxygen electrode. PMID:8680831

  12. Multi-site study of diffusion metric variability: effects of site, vendor, field strength, and echo time on regions-of-interest and histogram-bin analyses

    NASA Astrophysics Data System (ADS)

    Helmer, K. G.; Chou, M.-C.; Preciado, R. I.; Gimi, B.; Rollins, N. K.; Song, A.; Turner, J.; Mori, S.

    2016-03-01

    It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials.

  13. Quantifying diffuse and discrete venting at the Tour Eiffel vent site, Lucky Strike hydrothermal field

    NASA Astrophysics Data System (ADS)

    Mittelstaedt, Eric; EscartíN, Javier; Gracias, Nuno; Olive, Jean-Arthur; Barreyre, Thibaut; Davaille, Anne; Cannat, Mathilde; Garcia, Rafael

    2012-04-01

    The relative heat carried by diffuse versus discrete venting of hydrothermal fluids at mid-ocean ridges is poorly constrained and likely varies among vent sites. Estimates of the proportion of heat carried by diffuse flow range from 0% to 100% of the total axial heat flux. Here, we present an approach that integrates imagery, video, and temperature measurements to accurately estimate this partitioning at a single vent site, Tour Eiffel in the Lucky Strike hydrothermal field along the Mid-Atlantic Ridge. Fluid temperatures, photographic mosaics of the vent site, and video sequences of fluid flow were acquired during the Bathyluck'09 cruise (Fall, 2009) and the Momarsat'10 cruise (Summer, 2010) to the Lucky Strike hydrothermal field by the ROV Victor6000 aboard the French research vessel the "Pourquoi Pas"? (IFREMER, France). We use two optical methods to calculate the velocities of imaged hydrothermal fluids: (1) for diffuse venting, Diffuse Flow Velocimetry tracks the displacement of refractive index anomalies through time, and (2) for discrete jets, Particle Image Velocimetry tracks eddies by cross-correlation of pixel intensities between subsequent images. To circumvent video blurring associated with rapid velocities at vent orifices, exit velocities at discrete vents are calculated from the best fit of the observed velocity field to a model of a steady state turbulent plume where we vary the model vent radius and fluid exit velocity. Our results yield vertical velocities of diffuse effluent between 0.9 cm s-1 and 11.1 cm s-1 for fluid temperatures between 3°C and 33.5°C above that of ambient seawater, and exit velocities of discrete jets between 22 cm s-1 and 119 cm s-1 for fluid temperatures between 200°C and 301°C above ambient seawater. Using the calculated fluid velocities, temperature measurements, and photo mosaics of the actively venting areas, we calculate a heat flux due to diffuse venting from thin fractures of 3.15 ± 2.22 MW, discrete venting of

  14. Integration of geological, geochemical, and geophysical spatial data of the Cement oil field, Oklahoma, test site

    USGS Publications Warehouse

    Termain, Patricia A.; Donovan, Terrence J.; Chavez, Pat S.

    1980-01-01

    Measurement pertaining to geology, geochemistry, and geophysics of the Cement oil field, Oklahoma, test site were collected employing both airborne sensors and ground-based data collection. The measurements include: (1) airborne gamma-ray spectrometry (supplying bismuth 214, thalium 208, and potassium 40 gamma-ray intensities); (2) aeromagnetic survey data; (3) multi-frequency airborne resistivity survey data (supplying apparent electrical resistivity of near surface materials); (4) gravity data; (5) geological and topographic maps; and (6) image data from Landsat MSS and U-2 photography.

  15. Drivers of nitrogen dynamics in ecologically based agriculture revealed by long-term, high-frequency field measurements.

    PubMed

    Finney, Denise M; Eckert, Sara E; Kaye, Jason P

    2015-12-01

    Nitrogen (N) loss from agriculture impacts ecosystems worldwide. One strategy to mitigate these losses, ecologically based nutrient management (ENM), seeks to recouple carbon (C) and N cycles to reduce environmental losses and supply N to cash crops. However, our capacity to apply ENM is limited by a lack of field-based high-resolution data on N dynamics in actual production contexts. We used data from a five-year study of organic cropping systems to investigate soil inorganic N (SIN) variability and nitrate (NO3-) leaching in ENM. Four production systems initiated in 2007 and 2008 in central Pennsylvania varied in crop rotation, timing and intensity of tillage, inclusion of fallow periods, and N inputs. Extractable SIN was measured fortnightly from March through November throughout the experiment, and NO3- N concentration below the rooting zone was sampled with lysimeters during the first year of the 2008 start. We used recursive partitioning models to assess the importance of management and environmental factors to SIN variability and NO3- leaching and identify interactions between influential variables. Air temperature and tillage were the most important drivers of SIN across systems. The highest SIN concentrations occurred when the average air temperature three weeks prior to measurement was above 21 degrees C. Above this temperature and within 109 days of moldboard plowing, average SIN concentrations were 22.1 mg N/kg soil; 109 days or more past plowing average SIN dropped to 7.7 mg N/kg soil. Other drivers of SIN dynamics were N available from manure and cover crops. Highest average leachate NO3- N concentrations (15.2 ppm) occurred in fall and winter when SIN was above 4.9 mg/kg six weeks prior to leachate collection. Late season tillage operations leading to elevated SIN and leachate NO3- N concentrations were a strategy to reduce weeds while meeting consumer demand for organic products. Thus, while tillage that incorporates organic N inputs preceding cash

  16. The role of a fertilizer trial in reconciling agricultural expectations and landscape ecology requirements on an opencast coal site in South Wales, United Kingdom

    SciTech Connect

    Humphries, C.E.L.; Humphries, R.N.; Wesemann, H.

    1999-07-01

    Since the 1940s the restoration of opencast coal sites in the UK has been predominantly to productive agriculture and forestry. With new UK government policies on sustainability and biodiversity such land uses may be no longer be acceptable or appropriate in the upland areas of South Wales. A scheme was prepared for the upland Nant Helen site with the objective of restoring the landscape ecology of the site; it included acid grassland to provide the landscape setting and for grazing. The scheme met with the approval of the planning authority. An initial forty hectares (about 13% of the site) was restored between 1993 and 1996. While the approved low intensity grazing and low fertilizer regime met the requirements of the planning authority and the statutory agencies, it was not meeting the expectations of the grazers who had grazing rights to the land. To help reconcile the apparent conflict a fertilizer trial was set up. The trial demonstrated that additional fertilizer and intensive grazing was required to meet the nutritional needs of sheep. It also showed typical upland stocking densities of sheep could be achieved with the acid grassland without the need for reseeding with lowland types. However this was not acceptable to the authority and agencies as such fertilizer and grazing regimes would be detrimental to the landscape and ecological objectives of the restoration scheme. A compromise was agreed whereby grazing intensity and additional fertilizer have been zoned. This has been implemented and is working to the satisfaction of all parties. Without the fertilizer trial it is unlikely that the different interests could have been reconciled.

  17. A field strategy to monitor radioactivity associated with investigation derived wastes returned from deep drilling sites

    SciTech Connect

    Rego, J.H.; Smith, D.K.; Friensehner, A.V.

    1995-05-26

    The U.S. Department of Energy, Nevada Operations Office, Underground Test Area Operable Unit (UGTA) is drilling deep (>1500m) monitoring wells that penetrate both unsaturated (vadose) and saturated zones potentially contaminated by sub-surface nuclear weapons testing at the Nevada Test Site, Nye County, Nevada. Drill site radiological monitoring returns data on drilling effluents to make informed management decisions concerning fluid management. Because of rapid turn-around required for on-site monitoring, a representative sample will be analyzed simultaneously for {alpha}, {beta} and {gamma} emitters by instrumentation deployed on-site. For the purposes of field survey, accurate and precise data is returned, in many cases, with minimal sample treatment. A 30% efficient high purity germanium detector and a discriminating liquid scintillation detector are being evaluated for {gamma} and {alpha}/{beta} monitoring respectively. Implementation of these detector systems complements a successful on-site tritium monitoring program. Residual radioactivity associated with underground nuclear tests include tritium, activation products, fission products and actinides. Pulse shape discrimination (PSD) is used in {alpha}/{beta} liquid scintillation counting and is a function of the time distribution of photon emission. In particular, we hope to measure {sup 241}Am produced from {sup 241}Pu by {beta} decay. Because {sup 241}Pu is depleted in fissile bomb fuels, maximum PSD resolution will be required. The high purity germanium detector employs a multichannel analyzer to count gamma emitting radionuclides; we will designate specific window configurations to selectively monitor diagnostic fission product radionuclides (i.e., {sup 137}Cs).

  18. Field tests of 2- and 40-tube condensers at the East Mesa Geothermal Test Site

    SciTech Connect

    Murphy, R.W.; Domingo, N.

    1982-05-01

    Two water-cooled isobutane condensers, one with 2 tubes and one with 40 tubes, were subjected to field tests at the East Mesa Geothermal Test Site to assess relative heat transfer performance in both surface evaporator and direct-contact evaporator modes. The five groups of tests established that field performance was below earlier laboratory-determined levels and that direct-contact evaporator mode performance was poorer than that for the surface evaporator mode. In all test situations, fluted condenser tubes performed better than smooth condenser tubes. Cooling water quality had no significant effect on performance, but brine preflash in the direct-contact mode did promote some relative performance improvement. Important implications of these results for binary geothermal power plants are that (1) working-fluid-side impurities can significantly degrade heat transfer performance of the power plant condensers and (2) provisions for minimizing such impurities may be required.

  19. Directional changes of the geomagnetic field in West Africa: Insights from the metallurgical site of Korsimoro

    NASA Astrophysics Data System (ADS)

    Donadini, Fabio; Serneels, Vincent; Kapper, Lisa; El Kateb, Akram

    2015-11-01

    This work shows the first archeomagnetic directions from Western Africa measured on 32 iron smelting kilns dated between 650 and 1800 AD. The archeological excavation of the vast metallurgical site of Korsimoro established the existence of four distinct iron-smelting techniques. The time-frame of each technique could be clearly determined with radiocarbon dating. Many of the kilns investigated in this study could also be dated individually with residual charcoals found in their inside. The results indicate that the inclination of the field changed gradually from shallow normal to shallow reversed during 800 to 1300 AD, and then went back to shallow normal around 1600-1700 AD. The declination was instead stable around 10°E between 800 and 1400 AD, thereafter it started changing towards North. This trend correlates well with available secular variation curves from the Balkan and from Spain, and indicates that the field variation in West Africa was similar to the one in Europe.

  20. Spatiotemporal variations in growing season exchanges of CO2, H2O,and sensible heat in agricultural fields of the Southern GreatPlains

    SciTech Connect

    Fischer, Marc L.; Billesbach, David P.; Berry, Joseph A.; Riley,William J.; Torn, Margaret S.

    2007-06-13

    Climate, vegetation cover, and management create fine-scaleheterogeneity in unirrigated agricultural regions, with important but notwell-quantified consequences for spatial and temporal variations insurface CO2, water, and heat fluxes. We measured eddy covariance fluxesin seven agricultural fields--comprising winter wheat, pasture, andsorghum--in the U.S. Southern Great Plains (SGP) during the 2001-2003growing seasons. Land-cover was the dominant source of variation insurface fluxes, with 50-100 percent differences between fields planted inwinter-spring versus fields planted in summer. Interannual variation wasdriven mainly by precipitation, which varied more than two-fold betweenyears. Peak aboveground biomass and growing-season net ecosystem exchange(NEE) of CO2 increased in rough proportion to precipitation. Based on apartitioning of gross fluxes with a regression model, ecosystemrespiration increased linearly with gross primary production, but with anoffset that increased near the time of seed production. Because theregression model was designed for well-watered periods, it successfullyretrieved NEE and ecosystem parameters during the peak growing season,and identified periods of moisture limitation during the summer. Insummary, the effects of crop type, land management, and water limitationon carbon, water, and energy fluxes were large. Capturing the controllingfactors in landscape scale models will be necessary to estimate theecological feedbacks to climate and other environmental impactsassociated with changing human needs for agricultural production of food,fiber, and energy.

  1. Modeling unsaturated flow and transport processes at the Busted Butte Field Test Site, Nevada.

    PubMed

    Tseng, P-H; Soll, W E; Gable, C W; Turin, H J; Bussod, G Y

    2003-01-01

    A numerical model was used to simulate the flow and transport processes at the Busted Butte Field Test Site for the purpose of quantifying the effects of hydrogeologic conditions beneath the potential Yucca Mountain repository horizon. In situ experiments were conducted on a 10 x 10 x 7 m block comprising a layered Topopah Springs/Calico Hills formation with two imbedded faults. Tracer solution was continuously injected in eight parallel boreholes arranged on two horizontal planes. Twelve collection boreholes were emplaced perpendicular to the injection holes and were both horizontal and inclined. Solution samples were collected regularly using a sampling assembly consisting of an inverted membrane and sorbing-paper sampling pads. Comparisons between measurements and predictions show that, except for the occasional drops of concentrations observed in the field, the current model is able to capture the general characteristics of the system with varying levels of agreement using laboratory-measured mean hydraulic properties. Simulation results and field observations revealed a capillary-driven flow in the system. Good quantitative agreement is generally observed for near-field boreholes, however, this agreement deteriorates and the simulated solute concentration is underestimated at boreholes farther away from the injection points. Increasing the spatial resolution of the simulation improves the model predictions only to a limited extent. Scaling issues may need to be considered to describe flow and transport events, as the travel distance becomes large. PMID:12714297

  2. Field studies of the potential for wind transport of plutonium- contaminated soils at sites in Areas 6 and 11, Nevada Test Site

    SciTech Connect

    Lancaster, N.; Bamford, R.; Metzger, S.

    1995-07-01

    This report describes and documents a series of field experiments carried out in Areas 6 and 11 of the Nevada Test Site in June and July 1994 to determine parameters of boundary layer winds, surface characteristics, and vegetation cover that can be used to predict dust emissions from the affected sites. Aerodynamic roughness of natural sites is determined largely by the lateral cover of the larger and more permanent roughness elements (shrubs). These provide a complete protection of the surface from wind erosion. Studies using a field-portable wind tunnel demonstrated that natural surfaces in the investigated areas of the Nevada Test Site are stable except at very high wind speeds (probably higher than normally occur, except perhaps in dust devils). However, disturbance of silty-clay surfaces by excavation devices and vehicles reduces the entrainment threshold by approximately 50% and makes these areas potentially very susceptible to wind erosion and transport of sediments.

  3. Application of Geo-refrenced Geophysical Measurements to Precision Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop yield varies within a field because conventional farming manages fields uniformly with no consideration for spatial variability. Site-specific management units (SSMUs), a key component of precision agriculture, have been proposed as a means of handling the spatial variability of various factor...

  4. Remaining Sites Verification Package for the 331 Life Sciences Laboratory Drain Field Septic System, Waste Site Reclassification Form 2008-020

    SciTech Connect

    J. M. Capron

    2008-10-16

    The 331 Life Sciences Laboratory Drain Field (LSLDF) septic system waste site consists of a diversion chamber, two septic tanks, a distribution box, and a drain field. This septic system was designed to receive sanitary waste water, from animal studies conducted in the 331-A and 331-B Buildings, for discharge into the soil column. However, field observations and testing suggest the 331 LSLDF septic system did not receive any discharges. In accordance with this evaluation, the confirmatory sampling results support a reclassification of the 331 LSLDF waste site to No Action. This site does not have a deep zone or other condition that would warrant an institutional control in accordance with the 300-FF-2 ROD under the industrial land use scenario.

  5. Field application of innovative grouting agents for in situ stabilization of buried waste sites

    SciTech Connect

    Loomis, G.G.; Farnsworth, R.K.

    1997-12-31

    This paper presents field applications for two innovative grouting agents that were used to in situ stabilize buried waste sites, via jet grouting. The two grouting agents include paraffin and a proprietary iron oxide based cement grout called TECT. These materials were tested in specially designed cold test pits that simulate buried transuranic waste at the Idaho National Engineering Laboratory (INEL). The field demonstrations were performed at the INEL in an area referred to as the Cold Test Pit, which is adjacent to the INEL Radioactive Waste Management Complex (RWMC). At the RWMC, 56,000 m{sup 3} of transuranic (TRU) waste is co-mingled with over 170,000 m{sup 3} of soil in shallow land burial. Improving the confinement of this waste is one of the options for final disposition of this waste. Using jet-grouting technology to inject these materials into the pore spaces of buried waste sites results in the creation of buried monolithic waste forms that simultaneously protect the waste from subsidence, while eliminating the migratory potential of hazardous and radioactive contaminants in the waste.

  6. Precision agricultural systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Precision agriculture is a new farming practice that has been developing since late 1980s. It has been variously referred to as precision farming, prescription farming, site-specific crop management, to name but a few. There are numerous definitions for precision agriculture, but the central concept...

  7. Risk-Based Cleanup Actions for Closure of a Brown field Site

    SciTech Connect

    Rice, H.W.; Feild, J.F.; Farr Jr, L.C.

    2007-07-01

    Operating as a rail yard from approximately 1908 to 1987, Station Place is a 7.1-acre (4,046 square meter) property located in the downtown Portland, Oregon, River District Urban Renewal Area. The site soils were impacted with metals and polynuclear aromatic hydrocarbon compounds (PAHs). Benzene and select PAHs were detected in the shallow groundwater. Residual non-aqueous phase liquid (NAPL) was detected within the shallow saturated zone between 15 and 40 feet (4.5 to 12 meters) below grade and in the Troutdale Formation (used for municipal water supply at up-gradient location) at depths of up to 80 feet (24 meters) below grade. Site closure was obtained and redevelopment was completed at the site, by the Portland Development Commission and REACH Community Development, Inc., following the preparation of a baseline deterministic human health risk assessment, and beneficial land and water use determination to assess whether exposure to groundwater and soil posed a threat to human health or the environment. The property now provides affordable housing for the elderly and a city-owned parking garage. The housing provides substantial community benefit, allowing elderly people to live in a vibrant, exciting part of the city. Portland's city-owned parking garages also provide much needed parking space at reasonable rates. Both of these additions have changed an under-used Brown Field into affordable facilities, in a lively urban environment. (authors)

  8. MODIS tools for land validation, field site characterization, data intensive science and classroom education

    NASA Astrophysics Data System (ADS)

    Santhana Vannan, S.; Cook, R. B.; Wilson, B. E.

    2010-12-01

    The MODIS (Moderate Resolution Imaging Spectroradiometer) sensor data are highly useful for field research. The spectral, spatial and temporal characteristics of MODIS products have made them an important data source for analyzing key science questions relating to Earth System processes at regional, continental, and global scales. MODIS data are particularly useful to validate and inter-compare ground measurements at various field sites such as flux tower locations. MODIS data are also useful in land validation, understanding biogeochemical and ecological processes, and providing environmental data to support citizen science efforts. However, MODIS data volume and the complexity in data format makes MODIS data less usable in some cases. To solve this usability issue, the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) has developed a system that prepares and distributes subsets of selected MODIS land products in a scale and format useful for field researchers. Web and Web service tools provide MODIS subsets in ASCII format and in GIS compatible GeoTIFF format. Users can download and visualize MODIS subsets for a set of pre-defined locations, order MODIS subsets for any land location or automate the process of subset extraction using a SOAP based Web service. This paper provides a description of these tools and services with couple of application examples. The MODIS tools and services can be extended to support the large volume of data that would be produced by the various decadal survey missions. The MODIS subsets are provided for more than 1,000 sites across the globe. Most of the eddy covariance flux tower sites are included in the site list. The subsets are offered in tabular ASCII format and in GIS compatible GeoTIFF format. Time series plots and grid visualizations to help characterize field sites are also provided. In addition to offering subsets for fixed sites, the ORNL DAAC also offers the capability to create user

  9. Acceleration of Enzymatic conversion of Agricultural Waste Biomass into Bio-fuels by Low Intensity Uniform Ultrasound Field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the most critical stages of conversion of agricultural waste biomass into biofuels employs hydrolysis reactions between highly specific enzymes and matching substrates (e.g. corn stover cellulose with cellulase) that produce soluble sugars, which then could be converted into ethanol. Despite ...

  10. Use of vegetated agricultural drainage ditches to decrease pesticide transport from tomato and alfalfa fields in California: runoff toxicity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was performed to investigate the potential of vegetated drainage ditches for mitigating the impact of agricultural irrigation runoff on downstream aquatic ecosystems. Water column toxicity to larval fathead minnow (Pimephales promelas), and the amphipod, Hyalella azteca, was measured for ...

  11. Evaluation of the negative impacts of exposure to agricultural ditch water in fishes using streamside bioassays and field biomarkers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land use in regions of the Midwest is dominated by crop agriculture that depends on ditch drainage systems for maximum productivity. Many drainage networks comprise headwater streams that have been degraded by alteration of habitat and by introduction of agrichemicals. Understanding the relative i...

  12. Field performance in an agricultural setting of a wireless temperature monitoring system based on a low-cost infrared sensor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Continuous measurement of plant canopy temperature is useful in both research and production agriculture settings. Industrial-quality infrared thermometers which are often used for measurement of canopy temperatures, while reliable, are not always cost effective. For this study a relatively low-cost...

  13. Field test results for nitrogen removal by the constructed wetland component of an agricultural water recycling system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wetland Reservoir Subirrigation Systems (WRSIS) are innovative agricultural water recycling systems that can provide economic and environmental benefits. A constructed wetland is a main component of WRSIS, and an important function of this constructed wetland is drainage water treatment of nitrog...

  14. Evaluation of Aqua-Ammonia Chiller Technologies and Field Site Installation

    SciTech Connect

    Zaltash, Abdolreza

    2007-09-01

    The Naval Facilities Engineering Service Center (NFESC) has sponsored Oak Ridge National Laboratory (ORNL) to review, select, and evaluate advanced, gas-fired, 5-ton, aqua-ammonia, chiller technologies. The selection criteria was that units have COP values of 0.67 or better at Air-conditioning and Refrigeration Institute (ARI) 95 F outdoor rating conditions, an active refrigerant flow control, and a variable-speed condenser fan. These features are expected to allow these units to operate at higher ambient temperatures (up to the maximum operating temperature of 110 F) with minimal degradation in performance. ORNL evaluated three potential manufacturers of advanced, gas-fired, 5-ton, aqua-ammonia chillers-Robur, Ambian, and Cooling Technologies. Unfortunately, Robur did not meet the COP requirements and Cooling Technologies could not deliver a unit to be tested at the U.S. Department of Energy (DOE)-ORNL environmental chamber testing facility for thermally activated heat pumps. This eliminated these two technologies from further consideration, leaving only the Ambian chillers for evaluation. Two Ambian chillers were evaluated at the DOE-ORNL test facility. Overall these chillers operated well over a wide range of ambient conditions with minimal degradation in performance due to several control strategies used such as a variable speed condenser fan, a modulating burner, and active refrigerant flow control. These Ambian pre-commercial units were selected for installation and field testing at three federal facilities. NFESC worked with ORNL to assist with the site selection for installation and evaluation of these chillers. Two sites (ORNL and Naval Surface Warfare Center [NSWC] Corona) had a single chiller unit installed; and at one site (Naval Amphibious Base [NAB] Little Creek), two 5-ton chillers linked together were installed to provide 10 tons of cooling. A chiller link controller developed under this project was evaluated in the field test at Little Creek.

  15. Multi-site study of diffusion metric variability: characterizing the effects of site, vendor, field strength, and echo time using the histogram distance

    NASA Astrophysics Data System (ADS)

    Helmer, K. G.; Chou, M.-C.; Preciado, R. I.; Gimi, B.; Rollins, N. K.; Song, A.; Turner, J.; Mori, S.

    2016-03-01

    MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables.

  16. Effect of Tillage and Non-tillage Agricultural Practice on Nitrogen Losses as NO and N2O in Tropical Corn Fields at Guarico State, Venezuela.

    NASA Astrophysics Data System (ADS)

    Marquina, S.; Rojas, A.; Donoso, L.; Rasse, R.; Giuliante, A.; Corona, O.; Perez, T.

    2007-12-01

    We evaluated the effect of agricultural practices on NO and N2O emissions from corn fields at Northern Guárico, one of Venezuelan largest cereal production regions. Historically, the most common agricultural practice in these regions has been mono cropping. Tillage (T) and non-tillage (NT) of soils represent approximately 30 and 70% of the planted area, respectively. Comparative studies of the nitrogen losses associated with these agricultural practices are not available for these regions. This study was conducted at the farm "Tierra Nueva", Guárico State (9° 23' 33'' N, 66° 38' 30'' W) in two corn fields under tillage and non-tillage agricultural practice during the growing season (June-August 2006). A dry tropical forest, the primary ecosystem of the region, was evaluated for the same period of time. The corn and the forest fields were adjacent; therefore, they were exposed to the same meteorological conditions. The mean annual precipitation of the area is 622±97.3 mm (last 5 years). The soils are Vertisols (Typic Haplusterts). Nutrient soil concentrations (as nitrate and ammonium), water soil content and pH soil were measured in the fields for the same period of time. Soils were fertilized and planted simultaneously by a planting machine provided with a furrow opener where the fertilizer and seeds are incorporated between 0-10 cm depths. Tillage soils were fertilized on June 1st 2006 with 65 kgN/ha of NPK (13:18:16/3MgO, 3S; N as NH4Cl), whereas non-tillage soils were fertilized the next day with 56 kgN/ha of NPK (12:25:12/3MgO, 3S; N as NH4Cl). Second fertilization of both fields was done thirty-seven days later by broadcast adding 58 kgN/ha approximately, using nitrophosphate as fertilizer (NP 33-3: 33% N total; 16.7% N- NO3- and 16.6% N- NH4+). In general, NO and N2O soil emissions from both corn fields increased after fertilization events, and depend on water soil content and nutrient soil concentration. N2O soil emissions were 11 and 9 times larger in

  17. A FIELD EVALUATION OF IN-SITU BIODEGRADATION OF CHLORINATED ETHENES: PART I, METHODOLOGY AND FIELD SITE CHARACTERIZATION

    EPA Science Inventory

    Careful site characterization and implementation of quantitative monitoring methods are prerequisites for a convincing evaluation of enhanced biostimulation for aquifer restoration. This paper describes the characterization of a site at Moffett Naval Air Station, Mountain View, C...

  18. Water and carbon fluxes in rain fed agricultural sites under a changing climate: The role of stomata

    NASA Astrophysics Data System (ADS)

    Hosseini, A.; Gayler, S.; Streck, T.; Katul, G. G.

    2014-12-01

    Vegetation models are needed to assess how crop productivity may be altered due to variations in climatic conditions. Stomatal conductance controls both diffusion of CO2 from the atmosphere into the leaf and water losses from the soil-plant system to the atmosphere through transpiration (E). Despite its significance, stomatal conductance and its links to climatic variables remains empirically specified in current crop models thereby challenging their application to future climatic conditions. It has long been conjectured that stomata has evolved so as to allow terrestrial plants to assimilate CO2 in a desiccating atmosphere while minimizing water losses. Hence, the hypothesis that stomata adapt optimally to their environment so as to maximize assimilation (A) for a given amount of water loss has received significant attention over the past 4 decades. Here, a new approach to implement optimization theory of stomatal conductance into a dynamic canopy gas exchange model is introduced. A key variable in this theory is the so-called marginal water use efficiency (MWUE), which is assumed to be constant on time scales commensurate with fluctuations in stomatal aperture. However, on time scales relevant to crop productivity (daily to seasonal), the boundary conditions on the optimization problem evolve in time prompting the question of how to assign MWUE on such time scales. To address this question, MWUE was formulated as a function of time-integrated leaf-water potential and atmospheric CO2. Next, leaf water potential was linked to root and soil pressure using a soil water balance model based on a modified Richards' equation that considers vertical distribution of root water uptake. The adequacy of the new approach was tested by comparing predicted diurnal cycles of A and E as well as variability of soil moisture with long-term observations at a winter wheat (Triticum aestivum cv.Cubus) field in southwest Germany (see Figure), where transpiration and assimilation rates

  19. Implementation of a DOD ELAP Conforming Quality System at a FUSRAP Site Field Temporary Radiological Screening Laboratory - 13500

    SciTech Connect

    Winters, M.S.; McElheny, G.; Houston, L.M.; Masset, M.R.; Spector, H.L.

    2013-07-01

    A case study is presented on specific program elements that supported the transition of a temporary field radiological screening lab to an accredited operation capable of meeting client quality objectives for definitive results data. The temporary field lab is located at the Formerly Utilized Sites Remedial Action Program Linde Site in Tonawanda, NY. The site is undergoing remediation under the direction of the United States Army Corps of Engineers - Buffalo District, with Cabrera Services Inc. as the remediation contractor and operator of the on-site lab. Analysis methods employed in the on-site lab include gross counting of alpha and beta particle activity on swipes and air filters and gamma spectroscopy of soils and other solid samples. A discussion of key program elements and lessons learned may help other organizations considering pursuit of accreditation for on-site screening laboratories. (authors)

  20. Corrective measures technology for shallow land burial at arid sites: field studies of biointrusion barriers and erosion control

    SciTech Connect

    Nyhan, J.W.; Hakonson, T.E.; Lopez, E.A.

    1986-03-01

    The field research program involving corrective measures technologies for arid shallow land burial (SLB) sites is described. Results of field testing of a biointrusion barrier installed at a close-out waste disposal site (Area B) at Los Alamos are presented. Soil erosion and infiltration of water into a simulated trench cap with various surface treatments were measured, and the interaction between erosion control and subsurface water dynamics is discussed relative to waste management.

  1. Surgical Site Infection After Skin Excisions in Children: Is Field Sterility Sufficient?

    PubMed

    Nuzzi, Laura C; Greene, Arin K; Meara, John G; Taghinia, Amir; Labow, Brian I

    2016-03-01

    Skin excisions are common procedures in children. They may be performed in the clinic using field sterility or the operating room with strict sterile technique. We compared the effect of these locations and the use of antibiotics on the incidence of surgical site infection (SSI) after skin excisions. Patients ages 0-18 years presenting to our department for the excision of lesions from 2006 to 2010 with complete medical records were included in our study. Records were reviewed for demographic characteristics, presentation, perioperative conditions, and postoperative SSI and other wound complications. Analyses were performed to estimate the costs associated with sterility technique and perioperative antibiotic use. We identified 700 patients with a mean age of 9.1 years. Of 872 lesions excised, 0.3% resulted in SSI and 1.8% had other wound complications. The incidence of SSI did not vary according to sterility technique, antibiotic usage, surgeon, age, or lesion size, type, or location. The equipment costs to excise a lesion in the operating room were 200% greater than in the clinic. The incidence of SSI after excision of benign lesions in children did not differ between those performed using clinic field sterility and those using the standard aseptic sterile technique in the operating room. A considerable cost savings could be realized by adopting field sterility for simple excisions performed in the operating room and avoiding routine perioperative antibiotics in pediatric skin excisions. PMID:25727412

  2. SUPERFUND TREATABILITY CLEARINGHOUSE: SUMMARY REPORT ON THE FIELD INVESTIGATION OF THE SAPP BATTERY SITE JACKSON COUNTY, FLORIDA

    EPA Science Inventory

    This treatability study presents the results of field investigations at the Sapp Battery site in Florida, an abandoned battery recycling operation. The site is estimated to contain 14,300 cubic yards of soils with lead levels in excess of 1,000 ppm. The soils in the immediate v...

  3. Numerical simulations of water flow and tracer transport in soils at the USDA-ARS Beltsville OPE3 field site

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to develop a realistic model to simulate the complex processes of flow and tracer transport in USDA-ARS OPE3 field site and to compare simulation results with the detailed monitoring observations. The site has been studied for over 10 years with the extensive availabl...

  4. Efficient, Off-Grid LiDAR Scanning of Remote Field Sites

    NASA Astrophysics Data System (ADS)

    Gold, P.; Gold, R.; Cowgill, E.; Kreylos, O.; Hamann, B.

    2007-12-01

    As terrestrial LiDAR scanning systems become increasingly available, strategies for executing efficient field surveys in settings without access to the power grid are increasingly needed. To evaluate scan methods and develop an off-grid power system, we used a tripod-mounted laser scanner to create high resolution (≤40 mm point spacing) topographic maps for use in neotectonic studies of active faulting in arid, high elevation settings. We required 1-2 cm internal precision within point clouds spanning field sites that were ~300 x 300 m. Main components of our survey system included a Trimble GX DR200+ terrestrial laser scanner, a Leica TCR407power total station, a ruggedized laptop (2 GB RAM, 2.33 GHz dual-processor, and an Intel GMA 950 graphics card), batteries, and a portable photovoltaic array. Our first goal was to develop an efficient field-survey workflow. We started each survey project by using the total station for 1-2 days to locate an average of 8 ground control locations per site and to measure key geomorphic features within the project area. We then used the laser scanner to capture overlapping scans of the site, which required an average of six, 5-hour scanning sessions and an average of ten station setups. At each station, the scanner located itself on a particular point by measuring the relative positions of an average of four backsights, each of which is a ~17 x 17cm reflective target mounted on a tripod over the ground control point. To locate the scanner at a particular station prior to scanning, we experimented with both setting up over known points as measured using the total station, and resectioning, by positioning the scanner over an unmeasured location and backsighting on previously scanned points. We found that resectioning provided the smallest errors in scan registration. We then framed and queued a series of scans from each station that optimized point density and minimized data repetition. We also increased the accuracy of the

  5. The synergistic use of models and observations: understanding the mechanisms behind observed biomass dynamics at 14 Amazonian field sites and the implications for future biomass change

    NASA Astrophysics Data System (ADS)

    Levine, N. M.; Galbraith, D.; Christoffersen, B. J.; Imbuzeiro, H. A.; Restrepo-Coupe, N.; Malhi, Y.; Saleska, S. R.; Costa, M. H.; Phillips, O.; Andrade, A.; Moorcroft, P. R.

    2011-12-01

    The Amazonian rainforests play a vital role in global water, energy and carbon cycling. The sensitivity of this system to natural and anthropogenic disturbances therefore has important implications for the global climate. Some global models have predicted large-scale forest dieback and the savannization of Amazonia over the next century [Meehl et al., 2007]. While several studies have demonstrated the sensitivity of dynamic global vegetation models to changes in temperature, precipitation, and dry season length [e.g. Galbraith et al., 2010; Good et al., 2011], the ability of these models to accurately reproduce ecosystem dynamics of present-day transitional or low biomass tropical forests has not been demonstrated. A model-data intercomparison was conducted with four state-of-the-art terrestrial ecosystem models to evaluate the ability of these models to accurately represent structure, function, and long-term biomass dynamics over a range of Amazonian ecosystems. Each modeling group conducted a series of simulations for 14 sites including mature forest, transitional forest, savannah, and agricultural/pasture sites. All models were run using standard physical parameters and the same initialization procedure. Model results were compared against forest inventory and dendrometer data in addition to flux tower measurements. While the models compared well against field observations for the mature forest sites, significant differences were observed between predicted and measured ecosystem structure and dynamics for the transitional forest and savannah sites. The length of the dry season and soil sand content were good predictors of model performance. In addition, for the big leaf models, model performance was highest for sites dominated by late successional trees and lowest for sites with predominantly early and mid-successional trees. This study provides insight into tropical forest function and sensitivity to environmental conditions that will aid in predictions of the

  6. Radiocesium and radioiodine in soil particles agitated by agricultural practices: field observation after the Fukushima nuclear accident.

    PubMed

    Yamaguchi, N; Eguchi, S; Fujiwara, H; Hayashi, K; Tsukada, H

    2012-05-15

    Three weeks after the accident at the Fukushima Daiichi Nuclear Power Plant, we determined the activity concentrations of (131)I, (134)Cs and (137)Cs in atmospheric dust fugitively resuspended from soil particles due to soil surface perturbation by agricultural practices. The atmospheric concentrations of (131)I, (134)Cs and (137)Cs increased because of the agitation of soil particles by a hammer-knife mower and a rotary tiller. Coarse soil particles were primarily agitated by the perturbation of the soil surface of Andosols. For dust particles smaller than 10 μm, the resuspension factors of radiocesium during the operation of agricultural equipment were 16-times higher than those under background condition. Before tillage, most of the radionuclides accumulated within a few cm of the soil surface. Tillage diluted their concentration in the uppermost soil layer. PMID:22455974

  7. Distinguishing 'new' from 'old' organic carbon in reclaimed coal mine sites using thermogravimetry: II. Field validation

    SciTech Connect

    Maharaj, S.; Barton, C.D.; Karathanasis, T.A.D.; Rowe, H.D.; Rimmer, S.M.

    2007-04-15

    Thermogravimetry was used under laboratory conditions to differentiate 'new' and 'old' organic carbon (c) by using grass litter, coal, and limestone to represent the different C fractions. Thermogravimetric and derivative thermogravimetry curves showed pyrolysis peaks at distinctively different temperatures, with the peak for litter occurring at 270 to 395{sup o}C, for coal at 415 to 520 {sup o}C, and for limestone at 700 to 785{sup o}C. To validate this method in a field setting, we studied four reforested coal mine sites in Kentucky representing a chronosequence since reclamation: 0 and 2 years located at Bent Mountain and 3 and 8 years located at the Starfire mine. A nonmined mature (approximate to 80 years old) stand at Robinson Forest, Kentucky, was selected as a reference location. Results indicated a general peak increase in the 270 to 395{sup o}C region with increased time, signifying an increase in the 'new' organic matter (OM) fraction. For the Bent Mountain site, the OM fraction increased from 0.03 to 0.095% between years 0 and 2, whereas the Starfire site showed an increase from 0.095 to 1.47% between years 3 and 8. This equates to a C sequestration rate of 2.92 Mg ha{sup -1} yr{sup -1} for 'new' OM in the upper 10-cm layer during the 8 years of reclamation on eastern Kentucky reclaimed coal mine sites. Results suggest that stable isotopes and elemental data can be used as proxy tools for qualifying soil organic C (SOC) changes over time on the reclaimed coal mine sites but cannot be used to determine the exact SOC accumulation rate. However, results suggested that the thermogravimetric and derivative thermogravimetry methods can be used to quantify SOC accumulation and has the potential to be a more reliable, cost-effective, and rapid means to determine the new organic C fraction in mixed geological material, especially in areas dominated by coal and carbonate materials.

  8. Expedited characterization of ground water contamination at a large industrial site through field sampling and on-site analysis

    SciTech Connect

    Fusillo, T.V.; Potts, M.J.

    1995-09-01

    Ground water contamination by chlorinated solvents was detected at a former manufacturing facility in central New Jersey. The site, which occupies approximately 30 acres and is located in the Coastal Plain of New Jersey, is underlain by a thin layer of fine sand that extends to approximately 4 to 15 feet below ground surface (bgs) and a dense clay to silty clay that underlies the sand to a depth of at least 30 feet bgs, with ground water at a depth of 4 to 10 feet bgs. To expedite the ground water investigation, ENVIRON utilized a Geoprobe{reg_sign} sampling system together with an onsite mobile laboratory to perform site-wide ground water delineation sampling. Ground water samples were collected from the upper 5 feet of the water table using disposable tubing for on-site analysis of selected volatile organic compounds (VOCs) using a Photovac 10S Plus GC/PID. Sampling and analysis were conducted by On-Site Services of Newark, Delaware. Duplicate samples were also collected from all locations for analysis of VOCs by US EPA method 8240 at a commercial laboratory. Sampling began in the vicinity of the most highly contaminated monitoring well and proceeded in all directions until low or nondetectable concentrations were measured using the on-site GC or until the property boundaries were reached. Over the three-day sampling period, 33 ground water samples were collected. The sampling results provided a detailed picture of ground water quality across the large site, and contaminant distribution patterns confirmed the likely variability in ground water flow directions.

  9. Preliminary results of numerical investigations at SECARB Cranfield, MS field test site

    NASA Astrophysics Data System (ADS)

    Choi, J.; Nicot, J.; Meckel, T. A.; Chang, K.; Hovorka, S. D.

    2008-12-01

    The Southeast Regional Carbon Sequestration partnership sponsored by DOE has chosen the Cranfield, MS field as a test site for its Phase II experiment. It will provide information on CO2 storage in oil and gas fields, in particular on storage permanence, storage capacity, and pressure buildup as well as on sweep efficiency. The 10,300 ft-deep reservoir produced 38 MMbbl of oil and 677 MMSCF of gas from the 1940's to the 1960's and is being retrofitted by Denbury Resources for tertiary recovery. CO2 injection started in July 2008 with a scheduled ramp up during the next few months. The Cranfield modeling team selected the northern section of the field for development of a numerical model using the multiphase-flow, compositional CMG-GEM software. Model structure was determined through interpretation of logs from old and recently-drilled wells and geophysical data. PETREL was used to upscale and export permeability and porosity data to the GEM model. Preliminary sensitivity analyses determined that relative permeability parameters and oil composition had the largest impact on CO2 behavior. The first modeling step consisted in history-matching the total oil, gas, and water production out of the reservoir starting from its natural state to determine the approximate current conditions of the reservoir. The fact that pressure recovered in the 40 year interval since end of initial production helps in constraining boundary conditions. In a second step, the modeling focused on understanding pressure evolution and CO2 transport in the reservoir. The presentation will introduce preliminary results of the simulations and confirm/explain discrepancies with field measurements.

  10. IAEA workshop and field trial at the Oak Ridge K-25 Site

    SciTech Connect

    Hembree, D.M. Jr.; Ross, H.H.; Carter, J.A.

    1995-03-01

    In March 1994, members of the International Safeguards Department in the National Security Program Office (NSPO) hosted an environmental monitoring field trial workshop for International Atomic Energy Agency (IAEA) inspectors. The workshop was held at the Oak Ridge K-25 Site and its primary purpose was to train the inspectors in the techniques needed for effective environmental sample collection and handling. The workshop emphasized both sampling theory and practice. First, detailed techniques for swipe, vegetation, soil, biota, and water-associated sampling were covered in the classroom. Subsequently, the inspectors were divided into three groups for actual sample collection in and around the K-25 locale. The collected samples were processed by the Department of Energy (DOE) Network of Analytical Laboratories using established analytical techniques. This activity is part of the IAEA ``Programme 93+2 in. assessment of measures to enhance IAEA safeguards.

  11. Outdoor field evaluation of passive tritiated water vapor samplers at Canadian power reactor sites.

    PubMed

    Wood, M J

    1996-02-01

    Tritium is one of several radioactive nuclides routinely monitored in and around CANDU (CANada Deuterium Uranium) power reactor facilities. Over the last ten years, passive samplers have replaced active sampling devices for sampling tritiated water vapor in the workplace at many CANDU stations. The potential of passive samplers for outdoor monitoring has also been realized. This paper presents the results of a 1-y field trial carried out at all five Canadian CANDU reactor sites. The results indicate that passive samplers can be used at most sampling locations to measure tritiated water vapor in air concentrations as low as 1 Bq m-3 over a 30-d sampling period. Only in one of the five sampling locations was poor agreement observed between active and passive monitoring data. This location, however, was very windy and it is suspected that the gusty winds were the source of the discrepancies observed. PMID:8567295

  12. Field test of infrared thermography applied to biogas controlling in landfill sites

    NASA Astrophysics Data System (ADS)

    Madruga, Francisco J.; Muñoz, Jaime M.; González, Daniel A.; Tejero, Juan I.; Cobo, Adolfo; Gil, José L.; Conde, Olga M.; López-Higuera, Jose M.

    2007-04-01

    The gases accumulated inside the landfill as result of the fermentation of Municipal Solid Waste (MSW) known as biogas, are taking into consideration all possible uses as direct transformation into electricity. The system for collecting, regulating and controlling the biogas must include all the necessary safety features where the biogas leakage presents a high impact. Infrared thermography can be use to detect gas leakages due to the differences in temperature between the gas and the immediate surroundings. This method is able to monitor a wide area of landfill sites