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Sample records for agricultural sources including

  1. Use of a multi-isotope and multi-tracer approach including organic matter isotopes for quantifying nutrient contributions from agricultural vs wastewater sources

    NASA Astrophysics Data System (ADS)

    Kendall, C.; Silva, S. R.; Young, M. B.

    2013-12-01

    While nutrient isotopes are a well-established tool for quantifying nutrients inputs from agricultural vs wastewater treatment plant (WWTP) sources, we have found that combining nutrient isotopes with the C, N, and S isotopic compositions of dissolved and particulate organic matter, as part of a comprehensive multi-isotope and multi-tracer approach, is a much more diagnostic approach. The main reasons why organic matter C-N-S isotopes are a useful adjunct to studies of nutrient sources and biogeochemical processes are that the dissolved and particulate organic matter associated with (1) different kinds of animals (e.g., humans vs cows) often have distinctive isotopic compositions reflecting the different diets of the animals, and (2) the different processes associated with the different land uses (e.g., in the WWTP or associated with different crop types) often result in significant differences in the isotopic compositions of the organics. The analysis of the δ34S of particulate organic matter (POM) and dissolved organic matter (DOM) has been found to be especially useful for distinguishing and quantifying water, nutrient, and organic contributions from different land uses in aquatic systems where much of the organic matter is aquatic in origin. In such environments, the bacteria and algae incorporate S from sulfate and sulfide that is isotopically labeled by the different processes associated with different land uses. We have found that there is ~35 permil range in δ34S of POM along the river-estuary continuum in the San Joaquin/Sacramento River basin, with low values associated with sulfate reduction in the upstream wetlands and high values associated with tidal inputs of marine water into the estuary. Furthermore, rice agriculture results in relatively low δ34S values whereas WWTP effluent in the Sacramento River produces distinctly higher values than upstream of the WWTP, presumably because SO2 is used to treat chlorinated effluent. The fish living

  2. Perceptions of Vocational Agriculture Instructors Regarding Knowledge and Importance of Including Selected Agricultural Mechanics Units in the Vocational Agriculture Program.

    ERIC Educational Resources Information Center

    Heimgartner, Dale C.; Foster, Richard M.

    1981-01-01

    A survey of teachers in five northwestern states revealed that respondents in all states rated the units of arc welding and oxyacetylene welding as the most important units to be included in secondary vocational agriculture programs. (LRA)

  3. Ammonia emissions from non-agricultural sources in the UK

    NASA Astrophysics Data System (ADS)

    Sutton, M. A.; Dragosits, U.; Tang, Y. S.; Fowler, D.

    A detailed literature review has been undertaken of the magnitude of non-agricultural sources of ammonia (NH 3) in the United Kingdom. Key elements of the work included estimation of nitrogen (N) excreted by different sources (birds, animals, babies, human sweat), review of miscellaneous combustion sources, as well as identification of industrial sources and use of NH 3 as a solvent. Overall the total non-agricultural emission of NH 3 from the UK in 1996 is estimated here as 54 (27-106) kt NH 3-N yr -1, although this includes 11 (6-23) kt yr -1 from agriculture related sources (sewage sludge spreading, biomass burning and agro-industry). Compared with previous estimates for 1990, component source magnitudes have changed both because of revised average emissions per source unit (emission factors) and changes in the source activity between 1990 and 1996. Sources with larger average emission factors than before include horses, wild animals and sea bird colonies, industry, sugar beet processing, household products and non-agricultural fertilizer use, with the last three sources being included for the first time. Sources with smaller emission factors than before include: land spreading of sewage sludge, direct human emissions (sweat, breath, smoking, infants), pets (cats and dogs) and fertilizer manufacture. Between 1990 and 1996 source activities increased for sewage spreading (due to reduced dumping at sea) and transport (due to increased use of catalytic converters), but decreased for coal combustion. Combined with the current UK estimates of agricultural NH 3 emissions of 229 kt N yr -1 (1996), total UK NH 3 emissions are estimated at 283 kt N yr -1. Allowing for an import of reduced nitrogen (NH x) of 30 kt N yr -1 and deposition of 230 kt N yr -1, these figures imply an export of 83 kt NH 3-N yr -1. Although export is larger than previously estimated, due to the larger contribution of non-agricultural NH 3 emissions, it is still insufficient to balance the UK

  4. Source Units Developed as Part of an Internship Program in Agriculture/Agribusiness.

    ERIC Educational Resources Information Center

    Mannebach, Alfred J., Ed.

    This guide includes 12 source units of instruction developed by teachers of vocational agriculture who participated in an internship program in agriculture/agribusiness, which was designed to up-date the knowledge and skills of teachers of vocational agriculture in their areas of teaching specialization and to develop source units of instruction…

  5. The sources of deforestation - implications for sustainable agriculture in Brazil

    SciTech Connect

    Torres-Zorrilla, J.; Arnode, C.

    1992-12-01

    Agricultural equilibrium conditions are used to identify the sources of deforestation in Brazil. The rate which forestland can be converted into agricultural land and meet agricultural and environmental goals is calculated. This serves the task of determining how long agricultural land growth can be maintained until environmental targets are violated.

  6. Rationale for Research on Including Sustainable Agriculture in the High School Agricultural Education Curriculum.

    ERIC Educational Resources Information Center

    Williams, David L.; Dollisso, Awoke D.

    1998-01-01

    Sustainable agriculture is a multidisciplinary approach to food and fiber problems. Its inclusion in the secondary curriculum would enrich and align it with social concerns. Research is needed in the scholarship functions of discovery, integrative approaches, and teaching. (SK)

  7. 29 CFR 780.116 - Commodities included by reference to the Agricultural Marketing Act.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... commodity’ includes, in addition to other agricultural commodities, crude gum (oleoresin) from a living tree... spirits of turpentine made from gum (oleoresin) from a living tree” and “ ‘gum rosin’ means rosin...) of the Agricultural Marketing Act is that derived from a living tree, the production of...

  8. 29 CFR 780.116 - Commodities included by reference to the Agricultural Marketing Act.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... commodity’ includes, in addition to other agricultural commodities, crude gum (oleoresin) from a living tree... spirits of turpentine made from gum (oleoresin) from a living tree” and “ ‘gum rosin’ means rosin...) of the Agricultural Marketing Act is that derived from a living tree, the production of...

  9. 29 CFR 780.116 - Commodities included by reference to the Agricultural Marketing Act.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... commodity’ includes, in addition to other agricultural commodities, crude gum (oleoresin) from a living tree... spirits of turpentine made from gum (oleoresin) from a living tree” and “ ‘gum rosin’ means rosin...) of the Agricultural Marketing Act is that derived from a living tree, the production of...

  10. Minimizing agricultural nonpoint-source impacts: A symposium overview

    SciTech Connect

    Sharpley, A.; Meyer, M.

    1994-01-01

    This paper provides a brief overview of agricultural non-point pollution source issues and options. The need to identify critical sources for pollution control, target specific controls for different wter quality objectives within watersheds, and evaluate and implement cost effective management practices that minimize the pollution to ground water and surface waters are key issues.

  11. Management of agricultural nonpoint source pollution in China: current status and challenges.

    PubMed

    Wang, Xiaoyan

    2006-01-01

    Water quality in China shows an overall trend of deterioration in recent years. Nonpoint source pollution from agricultural and rural regions is the leading source of water pollution. The agricultural nonpoint source pollutants are mainly from fertilization of cropland, excessive livestock and poultry breeding and undefined disposal of daily living wastes in rural areas. Agricultural nonpoint sources contribute the main source of pollution to most watersheds in China, but they are ignored in management strategy and policy. Due to the lack of full understanding of water pollution control and management and the lack of perfect water quality standard systems and practical legislative regulations, agricultural nonpoint source pollution will become one of the biggest challenges to the sustainable development of rural areas and to society as a whole. The system for agricultural nonpoint source pollution control in China should include an appropriate legislation and policy framework, financing mechanisms, monitoring system, and technical guidelines and standards. The management of agricultural nonpoint source pollution requires multidisciplinary approaches that will involve a range of government departments, institutions and the public.

  12. Management of agricultural nonpoint source pollution in China: current status and challenges.

    PubMed

    Wang, Xiaoyan

    2006-01-01

    Water quality in China shows an overall trend of deterioration in recent years. Nonpoint source pollution from agricultural and rural regions is the leading source of water pollution. The agricultural nonpoint source pollutants are mainly from fertilization of cropland, excessive livestock and poultry breeding and undefined disposal of daily living wastes in rural areas. Agricultural nonpoint sources contribute the main source of pollution to most watersheds in China, but they are ignored in management strategy and policy. Due to the lack of full understanding of water pollution control and management and the lack of perfect water quality standard systems and practical legislative regulations, agricultural nonpoint source pollution will become one of the biggest challenges to the sustainable development of rural areas and to society as a whole. The system for agricultural nonpoint source pollution control in China should include an appropriate legislation and policy framework, financing mechanisms, monitoring system, and technical guidelines and standards. The management of agricultural nonpoint source pollution requires multidisciplinary approaches that will involve a range of government departments, institutions and the public. PMID:16594318

  13. Dissolved organic carbon source integration in an agricultural watershed

    NASA Astrophysics Data System (ADS)

    Hernes, P. J.; Spencer, R. G.; Dyda, R. Y.; Pellerin, B. A.; Bachand, P. A.; Bergamaschi, B. A.

    2012-12-01

    The dissolved organic carbon (DOC) chemistry and concentration at the mouth of a watershed represents an integrated signal of all sources and process that occur upstream of the mouth, however, the relative contributions of all those sources and processes to the chemistry and concentration is not equal. We sampled an agricultural watershed in the Sacramento River valley in California synoptically on multiple occasions in order to better identify the most important contributors to DOC chemistry. Our samples included headwater samples from native grasslands in three sub-catchments, samples within the agricultural portions of those sub-watersheds, samples near the conjunctions, and irrigation field inputs and outputs. DOC concentrations increase considerably in the agricultural portion of the watershed, demonstrating the impacts of anthropogenic disturbance of landscapes as well as the potential for local landscapes to contribute significantly to the overall DOC concentration and chemistry. The central sub-catchment in particular had significantly greater DOC concentrations, which appears to correspond to the much greater proportion of flood irrigation land management in this portion, as our field runoff measurements indicate much higher added DOC during flood irrigation than during furrow irrigation. Flow-weighted averaging of the three sub-catchment DOC concentrations does not replicate concentrations at the mouth (1-6 km downstream of the confluences), indicating the importance of in-stream processing and/or source inputs from riparian zones even along the mainstem. Optical characterization of DOC demonstrates changing chemistry from season to season, and differences in chemistry from different areas of the catchment. The storm-influenced spring sampling yielded higher carbon-specific UV absorbance at 254 nm (SUVA254), indicating a higher proportion of aromaticity, while the southern sub-catchment consistently yielded the highest spectral slope values, which

  14. 29 CFR 780.116 - Commodities included by reference to the Agricultural Marketing Act.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... commodity’ includes, in addition to other agricultural commodities, crude gum (oleoresin) from a living tree, and the following products as processed by the original producers of the crude gum (oleoresin) from which derived: Gum spirits of turpentine, and gum resin, as defined in the Naval Stores Act,...

  15. 29 CFR 780.116 - Commodities included by reference to the Agricultural Marketing Act.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... commodity’ includes, in addition to other agricultural commodities, crude gum (oleoresin) from a living tree, and the following products as processed by the original producers of the crude gum (oleoresin) from which derived: Gum spirits of turpentine, and gum resin, as defined in the Naval Stores Act,...

  16. Using Microbial Source Tracking to Enhance Environmental Stewardship of Agriculture

    NASA Astrophysics Data System (ADS)

    Martin, Sherry; Rose, Joan; Flood, Matthew; Aw, Tiong; Hyndman, David

    2016-04-01

    Large scale agriculture relies on the application of chemical fertilizers and animal manure. It is well known that nutrients in excess of a plant's uptake and soil retention capacity can travel to nearby waterways via surface run-off and groundwater pathways, indirectly fertilizing these aquatic ecosystems. It has not yet been possible to distinguish water quality impacts of fertilizer from those derived from human and animal waste sources. However, new microbial source tracking (MST) tools allow specific identification of fecal pollution. Our objective was to examine pollution risks at the regional scale using MST, mapping and classification and regression tree analysis. We present results Bovine M2 genetic marker data from three flow regimes (baseflow, snow melt, and post-planting rain). Key landscape characteristics were related to the presence of the bovine markers and appear to be related to fate and transport. Impacts at this regional watershed scale will be discussed. Our research aims to identify the impacts of agricultural management practices on water quality by linking nutrient concentrations with fecal pollution sources. We hope that our research will provide guidance that will help improve water quality through agricultural best management practices to reduce pathogen contamination.

  17. Sediment fingerprinting in agricultural catchments: A critical re-examination of source discrimination and data corrections

    NASA Astrophysics Data System (ADS)

    Smith, Hugh G.; Blake, William H.

    2014-01-01

    Fine sediment source fingerprinting techniques have been widely applied in agricultural river catchments. Successful source discrimination in agricultural environments depends on the key assumption that land-use source signatures imprinted on catchment soils are decipherable from those due to other landscape factors affecting soil and sediment properties. In this study, we re-examine this critical assumption by investigating (i) the physical and chemical basis for source discrimination and (ii) potential factors that may confound source un-mixing in agricultural catchments, including particle size and organic matter effects on tracer properties. The study is situated in the River Tamar, a predominantly agricultural catchment (920 km2) in south-west England that has also been affected by mining. Source discrimination focused on pasture and cultivated land uses and channel banks. Monthly, time-integrated suspended sediment samples were collected across seven catchments for a 12-month period. Physical and chemical properties measured in source soils and sediment included fallout radionuclides (137Cs, excess 210Pb), major and minor element geochemical constituents, total organic carbon and particle size. Source discrimination was entirely dependent on differences in tracer property concentrations between surface and sub-surface soils. This is based on fallout radionuclide concentrations that are surface-elevated, while many geochemical properties are surface-depleted due to weathering and pedogenetic effects, although surface soil contamination can reverse this trend. However, source discrimination in the study catchments was limited by (i) rotation of cultivated and pasture fields resulting in reduced differences between these two sources, and (ii) the cultivated source signature resembling a mix of the pasture and channel bank sources for many tracer properties. Furthermore, a combination of metal pollution from abandoned historic mines and organic enrichment of

  18. 25 CFR 162.219 - Are there any provisions that must be included in an agricultural lease?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... agricultural lease? 162.219 Section 162.219 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER LEASES AND PERMITS Agricultural Leases Lease Requirements § 162.219 Are there any provisions that must be included in an agricultural lease? In addition to the other requirements of this part,...

  19. 25 CFR 162.219 - Are there any provisions that must be included in an agricultural lease?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... agricultural lease? 162.219 Section 162.219 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER LEASES AND PERMITS Agricultural Leases Lease Requirements § 162.219 Are there any provisions that must be included in an agricultural lease? In addition to the other requirements of this part,...

  20. 25 CFR 162.219 - Are there any provisions that must be included in an agricultural lease?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... agricultural lease? 162.219 Section 162.219 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER LEASES AND PERMITS Agricultural Leases Lease Requirements § 162.219 Are there any provisions that must be included in an agricultural lease? In addition to the other requirements of this part,...

  1. 25 CFR 162.219 - Are there any provisions that must be included in an agricultural lease?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... agricultural lease? 162.219 Section 162.219 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER LEASES AND PERMITS Agricultural Leases Lease Requirements § 162.219 Are there any provisions that must be included in an agricultural lease? In addition to the other requirements of this part,...

  2. 25 CFR 162.219 - Are there any provisions that must be included in an agricultural lease?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... agricultural lease? 162.219 Section 162.219 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER LEASES AND PERMITS Agricultural Leases Lease Requirements § 162.219 Are there any provisions that must be included in an agricultural lease? In addition to the other requirements of this part,...

  3. Arena retrofit includes ground-source heat pump

    SciTech Connect

    Hodgson, S.F.

    1996-01-01

    The venue for Sacramento`s first professional basketball games was the {open_quotes}old Arco Arena,{close_quotes} built in 1985 just north of the downtown area and converted to offices after a large, permanent arena was constructed. In 1994, the {open_quotes}old arena{close_quotes} was acquired by a California general partnership called Del Paso Venture. To heat and cool the 3-story, 211,000-square foot structure, Del Paso has installed a ground-source heat pump system. The project is significant for the ground-source heat pump industry, because this is the first ground-source heat pump site ever designed specifically for the energy load of the building it will serve. Other projects have been calculated by rule-of-thumb. The installation and cost of the heat pump system are discussed.

  4. [Spatial distribution and pollution source identification of agricultural non-point source pollution in Fujiang watershed].

    PubMed

    Ding, Xiao-Wen; Shen, Zhen-Yao

    2012-11-01

    In order to provide regulatory support for management and control of non-point source (NPS) pollution in Fujiang watershed, agricultural NPS pollution is simulated, spatial distribution characteristics of NPS pollution are analyzed, and the primary pollution sources are also identified, by export coefficient model (ECM) and geographic information system (GIS). Agricultural NPS total nitrogen (TN) loading was of research area was 9.11 x 10(4) t in 2010, and the average loading was intensity was 3.10 t x km(-2). Agricultural NPS TN loading mainly distributed over dry lands, Mianyang city and gentle slope areas; high loading intensity areas were dry lands, Deyang city and gentle slope areas. Agricultural land use, of which contribution rate was 62. 12%, was the most important pollution source; fertilizer loss in dry lands, of which contribution rate was 50.49%, was the prominent. Improving methods of agricultural cultivation, implementing "farm land returning to woodland" policy, and enhancing treatment efficiency of domestic sewage and livestock waster wate are effective measures.

  5. Tracing crop-specific sediment sources in agricultural catchments

    NASA Astrophysics Data System (ADS)

    Blake, William H.; Ficken, Katherine J.; Taylor, Philip; Russell, Mark A.; Walling, Desmond E.

    2012-02-01

    A Compound Specific Stable Isotope (CSSI) sediment tracing approach is evaluated for the first time in an agricultural catchment setting against established geochemical fingerprinting techniques. The work demonstrates that novel CSSI techniques have the potential to provide important support for soil resource management policies and inform sediment risk assessment for the protection of aquatic habitats and water resources. Analysis of soil material from a range of crop covers in a mixed land-use agricultural catchment shows that the carbon CSSI signatures of particle-reactive fatty acids label surface agricultural soil with distinct crop-specific signatures, thus permitting sediment eroded from each land-cover to be tracked downstream. High resolution sediment sampling during a storm event and analysis for CSSI and conventional geochemical fingerprints elucidated temporal patterns of sediment mobilisation under different crop regimes and the specific contribution that each crop type makes to downstream sediment load. Pasture sources (65% of the catchment area) dominated the sediment load but areal yield (0.13 ± 0.02 t ha - 1 ) was considerably less than that for winter wheat (0.44 ± 0.15 t ha - 1 ). While temporal patterns in crop response matched runoff and erosion response predictions based on plot-scale rainfall simulation experiments, comparison of biomarker and geochemical fingerprinting data indicated that the latter overestimated cultivated land inputs to catchment sediment yield due to inability to discriminate temporary pasture (in rotation) from cultivated land. This discrepancy, however, presents an opportunity since combination of the two datasets revealed the extremely localised nature of erosion from permanent pasture fields in this system (estimated at up to 0.5 t ha - 1 ). The novel use of CSSI and geochemical tracers in tandem provided unique insights into sediment source dynamics that could not have been derived from each method alone. Research

  6. Natural radiation sources, including some lessons for nuclear waste management

    NASA Astrophysics Data System (ADS)

    Métivier, Henri

    2002-09-01

    The average effective dose at the global level is, according to UNSCEAR, estimated to be 2.4 mSv from naturally occurring sources. This average value can be divided as follows: 1.3 mSv associated with radon, 0.39 mSv from cosmic radiation, 0.46 mSv from terrestrial radiation, and 0.23 mSv from internal radiation, radon excluded. These values can vary quite significantly depending on the place of habitation. Despite this large variation, no sound epidemiological study has yet shown the health effects on the most exposed populations, apart from a few studies concerning radon, but in which the predominant role of tobacco is difficult to determine. To cite this article: H. Métivier, C. R. Physique 3 (2002) 1035-1048.

  7. Evaluation of agricultural nonpoint source pollution potential risk over China with a Transformed-Agricultural Nonpoint Pollution Potential Index method.

    PubMed

    Yang, Fei; Xu, Zhencheng; Zhu, Yunqiang; He, Chansheng; Wu, Genyi; Qiu, Jin Rong; Fu, Qiang; Liu, Qingsong

    2013-01-01

    Agricultural nonpoint source (NPS) pollution has been the most important threat to water environment quality. Understanding the spatial distribution of NPS pollution potential risk is important for taking effective measures to control and reduce NPS pollution. A Transformed-Agricultural Nonpoint Pollution Potential Index (T-APPI) model was constructed for evaluating the national NPS pollution potential risk in this study; it was also combined with remote sensing and geographic information system techniques for evaluation on the large scale and at 1 km2 spatial resolution. This model considers many factors contributing to the NPS pollution as the original APPI model, summarized as four indicators of the runoff, sediment production, chemical use and the people and animal load. These four indicators were analysed in detail at 1 km2 spatial resolution throughout China. The T-APPI model distinguished the four indicators into pollution source factors and transport process factors; it also took their relationship into consideration. The studied results showed that T-APPI is a credible and convenient method for NPS pollution potential risk evaluation. The results also indicated that the highest NPS pollution potential risk is distributed in the middle-southern Jiangsu province. Several other regions, including the North China Plain, Chengdu Basin Plain, Jianghan Plain, cultivated lands in Guangdong and Guangxi provinces, also showed serious NPS pollution potential. This study can provide a scientific reference for predicting the future NPS pollution risk throughout China and may be helpful for taking reasonable and effective measures for preventing and controlling NPS pollution.

  8. Sole-Source Lighting for Controlled-Environment Agriculture

    NASA Technical Reports Server (NTRS)

    Mitchell.Cary; Stutte, Gary W.

    2015-01-01

    Since plants on Earth evolved under broad-spectrum solar radiation, anytime they are grown exclusively under electric lighting that does not contain all wavelengths in similar proportion to those in sunlight, plant appearance and size could be uniquely different. Nevertheless, plants have been grown for decades under fluorescent (FL) (1) + incandescent (IN) (2) lamps as a sole source of lighting (SSL), and researchers have become comfortable that, in certain proportions of FL + IN for a given species, plants can appear "normal" relative to their growth outdoors. The problem with using such traditional SSLs for commercial production typically is short lamp lifespans and not obtaining enough photosynthetically active radiation (PAR, 400-700 nm) when desired. These limitations led to supplementation of FL + IN lamp outputs with longer-lived, high-intensity discharge (HID) lamps in growth chambers (3). As researchers became comfortable that mixes of orange-biased high-pressure sodium (HPS) and blue-biased metal halide (MH) HIDs together also could give normal plant growth at higher intensities, growth chambers and phytotrons subsequently were equipped mainly with HID lamps, with their intense thermal output filtered out by ventilated light caps or thermal-controlled water barriers. For the most part, IN and HID lamps have found a home in commercial protected horticulture, usually for night-break photoperiod lighting (IN) or for seasonal supplemental lighting (mostly HPS) in greenhouses. However, lack of economically viable options for SSL have held back aspects of year-round indoor agriculture from taking off commercially.

  9. Modelling Mediterranean agro-ecosystems by including agricultural trees in the LPJmL model

    NASA Astrophysics Data System (ADS)

    Fader, M.; von Bloh, W.; Shi, S.; Bondeau, A.; Cramer, W.

    2015-11-01

    In the Mediterranean region, climate and land use change are expected to impact on natural and agricultural ecosystems by warming, reduced rainfall, direct degradation of ecosystems and biodiversity loss. Human population growth and socioeconomic changes, notably on the eastern and southern shores, will require increases in food production and put additional pressure on agro-ecosystems and water resources. Coping with these challenges requires informed decisions that, in turn, require assessments by means of a comprehensive agro-ecosystem and hydrological model. This study presents the inclusion of 10 Mediterranean agricultural plants, mainly perennial crops, in an agro-ecosystem model (Lund-Potsdam-Jena managed Land - LPJmL): nut trees, date palms, citrus trees, orchards, olive trees, grapes, cotton, potatoes, vegetables and fodder grasses. The model was successfully tested in three model outputs: agricultural yields, irrigation requirements and soil carbon density. With the development presented in this study, LPJmL is now able to simulate in good detail and mechanistically the functioning of Mediterranean agriculture with a comprehensive representation of ecophysiological processes for all vegetation types (natural and agricultural) and in a consistent framework that produces estimates of carbon, agricultural and hydrological variables for the entire Mediterranean basin. This development paves the way for further model extensions aiming at the representation of alternative agro-ecosystems (e.g. agroforestry), and opens the door for a large number of applications in the Mediterranean region, for example assessments of the consequences of land use transitions, the influence of management practices and climate change impacts.

  10. Modelling Mediterranean agro-ecosystems by including agricultural trees in the LPJmL model

    NASA Astrophysics Data System (ADS)

    Fader, M.; von Bloh, W.; Shi, S.; Bondeau, A.; Cramer, W.

    2015-06-01

    Climate and land use change in the Mediterranean region is expected to affect natural and agricultural ecosystems by decreases in precipitation, increases in temperature as well as biodiversity loss and anthropogenic degradation of natural resources. Demographic growth in the Eastern and Southern shores will require increases in food production and put additional pressure on agro-ecosystems and water resources. Coping with these challenges requires informed decisions that, in turn, require assessments by means of a comprehensive agro-ecosystem and hydrological model. This study presents the inclusion of 10 Mediterranean agricultural plants, mainly perennial crops, in an agro-ecosystem model (LPJmL): nut trees, date palms, citrus trees, orchards, olive trees, grapes, cotton, potatoes, vegetables and fodder grasses. The model was successfully tested in three model outputs: agricultural yields, irrigation requirements and soil carbon density. With the development presented in this study, LPJmL is now able to simulate in good detail and mechanistically the functioning of Mediterranean agriculture with a comprehensive representation of ecophysiological processes for all vegetation types (natural and agricultural) and in a consistent framework that produces estimates of carbon, agricultural and hydrological variables for the entire Mediterranean basin. This development pave the way for further model extensions aiming at the representation of alternative agro-ecosystems (e.g. agroforestry), and opens the door for a large number of applications in the Mediterranean region, for example assessments on the consequences of land use transitions, the influence of management practices and climate change impacts.

  11. [Spatial heterogeneity and classified control of agricultural non-point source pollution in Huaihe River Basin].

    PubMed

    Zhou, Liang; Xu, Jian-Gang; Sun, Dong-Qi; Ni, Tian-Hua

    2013-02-01

    Agricultural non-point source pollution is of importance in river deterioration. Thus identifying and concentrated controlling the key source-areas are the most effective approaches for non-point source pollution control. This study adopts inventory method to analysis four kinds of pollution sources and their emissions intensity of the chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in 173 counties (cities, districts) in Huaihe River Basin. The four pollution sources include livestock breeding, rural life, farmland cultivation, aquacultures. The paper mainly addresses identification of non-point polluted sensitivity areas, key pollution sources and its spatial distribution characteristics through cluster, sensitivity evaluation and spatial analysis. A geographic information system (GIS) and SPSS were used to carry out this study. The results show that: the COD, TN and TP emissions of agricultural non-point sources were 206.74 x 10(4) t, 66.49 x 10(4) t, 8.74 x 10(4) t separately in Huaihe River Basin in 2009; the emission intensity were 7.69, 2.47, 0.32 t.hm-2; the proportions of COD, TN, TP emissions were 73%, 24%, 3%. The paper achieves that: the major pollution source of COD, TN and TP was livestock breeding and rural life; the sensitivity areas and priority pollution control areas among the river basin of non-point source pollution are some sub-basins of the upper branches in Huaihe River, such as Shahe River, Yinghe River, Beiru River, Jialu River and Qingyi River; livestock breeding is the key pollution source in the priority pollution control areas. Finally, the paper concludes that pollution type of rural life has the highest pollution contribution rate, while comprehensive pollution is one type which is hard to control.

  12. Regulatory Control of Sealed Sources in Germany including Regulations Regarding Spent and Disused Sources - 13176

    SciTech Connect

    Dollan, Ralph; Haeusler, Uwe; Czarwinski, Renate

    2013-07-01

    Effective regulatory control is essential to ensure the safe and secure use of radioactive material and the appropriate management of radioactive waste. To ensure a sustainable control of high radioactive sources, the European Commission published the Council Directive 2003/122/EURATOM on the control of high-activity sealed radioactive sources and orphan sources, which had to be transferred into national legislation by all member states of the European Union. Major requirement of the Directive is a system to ensure traceability of high-activity sealed sources from 'cradle to grave' as well as the provision to take back disused sources by the supplier or manufacturer. With the Act on high-activity sealed radioactive sources Germany implemented the requirements of the Directive 2003/122/EURATOM and established a national registry of high-activity sealed sources in 2006. Currently, about 27.000 high-activity sealed sources are recorded in this national registry. (authors)

  13. Potential alternative fuel sources for agricultural crops and plant components

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The changing landscape of agricultural production is placing unprecedented demands on farmers as they face increasing global competition and greater natural resource conservation challenges. However, shrinking profit margins due to increasing input costs, particularly of fuel and fertilizer, can res...

  14. Critical source times for nutrient loss in agricultural catchment streams

    NASA Astrophysics Data System (ADS)

    Melland, Alice; Shore, Mairead; Mellander, Per-Erik; McDonald, Noeleen; Shortle, Ger; Murphy, Paul; Jordan, Phil

    2014-05-01

    Identifying periods of the year when there is a high risk of incidental nutrient loss from farms via runoff to streams underpins current nutrient management legislation in Europe. This research explored high-temporal resolution nutrient transfer patterns relative to the time that manure and fertiliser are prohibited from being spread (the mandatory spreading 'closed' period) in five Irish agricultural catchments. Catchment nutrient losses during the 12 week closed periods in 2009-10, 2010-11 and 2011-12 were compared with losses during the remainder of the year, and with losses in the two week 'shoulder' periods immediately before and after the closed period. The closed period losses were assumed to be residual from soil nutrient stores and the 'shoulder' periods were considered to also include incidental losses. Nutrient loss was measured at sub-hourly frequency as total phosphorus (P) and total oxidised nitrogen (mostly nitrate-N) fluxes in streamflow. The streamflow fluxes showed that the proportion of the annual nitrate-N loss occurring during the closed periods (33-61%) was high compared with the remainder of the year. Six to ten times more nitrate-N loss occurred in the two weeks after, compared with the two weeks before, the closed period. These two week 'shoulder' period losses were, on average, less than or equal to 2.5 kg nitrate-N/ha and 9% of total annual nitrate-N loss in streamflow. On average, 40-53% of the annual P loss occurred during the closed periods but in a runoff-prone catchment in a year with a wet summer, the closed period was the less risky period. Similar to nitrate-N, two to twenty times more P loss occurred in the two weeks after, compared with the two weeks before, the closed period. These shoulder period losses were, on average, less than or equal to 0.027 kg/ha and 4.2% of total annual P loss in streamflow. The proportion of the shoulder period loss that could be attributed to recently spread nutrients was not known but can be

  15. ASSESSMENT OF RISK REDUCTION STRATEGIES FOR THE MANAGEMENT OF AGRICULTURAL NONPOINT SOURCE PESTICIDE RUNOFF IN ESTUARINE ECOSYSTEMS

    EPA Science Inventory

    Agricultural nonpoint source (NPS) runoff may result in significant discharges of pesticides, suspended sediments, and fertilizers into estuarine habitats adjacent to agricultural areas or downstream from agricultural watersheds. Exposure of estuarine fin fish and shellfish to to...

  16. Food and agricultural waste: Sources of carbon for ethanol production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the past, wastes derived from agriculture products have met with limited success in the production of biofuels. Our objective in this report is to showcase a new and meaningful concept (called “avoidance”), to measure the environmental importance of converting these waste streams into energy. Agr...

  17. Reference Sources in Science, Engineering, Medicine, and Agriculture.

    ERIC Educational Resources Information Center

    Malinowsky, H. Robert

    This document is a bibliographic guide of over 2,400 titles in science, engineering, medicine and agriculture. This book is intended for use by librarians for reference updates, researchers and students who need to access information but who are unfamiliar with the particular discipline, and for information science students learning about the…

  18. Optimization strategy integrity for watershed agricultural non-point source pollution control based on Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Gong, Y.; Yu, Y. J.; Zhang, W. Y.

    2016-08-01

    This study has established a set of methodological systems by simulating loads and analyzing optimization strategy integrity for the optimization of watershed non-point source pollution control. First, the source of watershed agricultural non-point source pollution is divided into four aspects, including agricultural land, natural land, livestock breeding, and rural residential land. Secondly, different pollution control measures at the source, midway and ending stages are chosen. Thirdly, the optimization effect of pollution load control in three stages are simulated, based on the Monte Carlo simulation. The method described above is applied to the Ashi River watershed in Heilongjiang Province of China. Case study results indicate that the combined three types of control measures can be implemented only if the government promotes the optimized plan and gradually improves implementation efficiency. This method for the optimization strategy integrity for watershed non-point source pollution control has significant reference value.

  19. Mitigation strategies for methane emissions from agricultural sources

    SciTech Connect

    Duxbury, J.M.

    1993-12-31

    Anthropogenic emissions of CH{sub 4} account for 70% of total global emissions of this greenhouse gas. Current anthropogenic emissions of CH{sub 4} in the US are estimated to be between 24-30 Tg CH{sub 4} or 7-9% of the global anthropogenic total. By comparison the US is responsible for 27% of anthropogenic emissions of CO{sub 2} from fossil fuel use. Table 1 shows that the major anthropogenic sources of CH{sub 4} in the US are landfills (37%), domestic livestock and livestock waste (31%) and the coal mining/natural gas/petroleum industries (28%). On a global basis it is estimated that US landfills contribute 30% to the global landfill total, whereas livestock (including waste) and the coal mining/natural gas/petroleum industries each contribute about 8% to their respective global totals. The US is an insignificant contributor (< 1%) to global emissions of CH{sub 4} from rice paddies.

  20. Using Strontium Isotopes in Arid Agricultural Soils to Determine a Sink or Source of CO2

    NASA Astrophysics Data System (ADS)

    Ortiz, A. C.; Jin, L.

    2014-12-01

    Arid and semi-arid regions of the world are predicted to continue to expand through land degradation and prolonged drought events. Agricultural practices in these drylands degrade soils through elevated salinity, sodicity and alkalinity. Indeed, flood irrigation loads salts onto the soils including carbonate minerals in the form of calcite. Alfalfa and Pecan are salt tolerant and commonly grown in the arid El Paso region, but need irrigation using Rio Grande water with little to no contribution from local ground waters. We hypothesize that the irrigation is loading extra Ca and bicarbonate to soils and anthropogenically enhancing the precipitation of carbonates. We intend to monitor soil CO2 efflux after irrigation, characterize soil minerals, and combine them to isotopic data of soil, irrigation, and drainage waters to link the sources of Ca and C, kinetics of calcite precipitation, to irrigation events. This will include strontium isotopic analysis to determine the source of calcium in the agricultural fields, U-disequilibrium isotopes to estimate the carbonate ages, and CO2 efflux to monitor atmosphere-soil exchange. Carbon dioxide emissions are expected to change during flood irrigation when soils are saturated. After irrigation events, evaporative effects increase Ca and dissolved inorganic carbon concentration in soil waters leading to precipitation of calcite and thus elevated CO2efflux. Preliminary measurements in the pecan field show a marginally significant difference in CO2 fluxes before and after irrigation (p=0.07, t-test). Carbon dioxide emissions are lower during moist conditions (0.6 g m-2hr-1 CO2) than those in dry conditions (1.0 g m-2hr-1 CO2). Future C isotope data are needed to identify the source of extra CO2, biogenic or calcite-precipitation related. A water leachable extraction of alfalfa soils shows 87Sr/86Sr ratios ranged from 0.7101 to 0.7103, indicating Rio Grande river as a dominant calcium source. Further Sr isotopic analysis of

  1. Agricultural Science Teachers' Barriers, Roles, and Information Source Preferences for Teaching Biotechnology Topics

    ERIC Educational Resources Information Center

    Mowen, Diana L.; Wingenbach, Gary J.; Roberts, T. Grady; Harlin, Julie F.

    2007-01-01

    The purpose of this study was to determine barriers, roles, and information source preferences for teaching agricultural biotechnology topics. Agricultural science teachers were described primarily as 37 year-old males who had taught for 12 years, had bachelor's degrees, and had lived or worked on a farm or ranch. Equipment was perceived as the…

  2. Economic Analysis of Nitrate Source Reductions in California Agriculture

    NASA Astrophysics Data System (ADS)

    Medellin-Azuara, J.; Howitt, R.; Rosenstock, T.; Harter, T.; Pettygrove, S. G.; Dzurella, K.; Lund, J. R.

    2011-12-01

    We present an analytical approach to assess the economic impact of improving nitrogen management practices in California agriculture. We employ positive mathematical programming to calibrate crop production to base input information. The production function representation is a nested constant elasticity of substitution with two nests: one for applied water and one for applied nitrogen. The first nest accounts for the tradeoffs between irrigation efficiency and capital investments in irrigation technology. The second nest represents the tradeoffs between nitrogen application efficiency and the marginal costs of improving nitrogen efficiency. In the production function nest, low elasticities of substitution and water and nitrogen stress constraints keep agricultural crop yields constant despite changes in nitrogen management practices. We use the Tulare Basin, and the Salinas Valley in California's Central Valley and Central Coast respectively as our case studies. Preliminary results show that initial reductions of 25% in nitrogen loads to groundwater may not impose large costs to agricultural crop production as substitution of management inputs results in only small declines in net revenue from farming and total land use. Larger reductions in the nitrogen load to groundwater of 50% imposes larger marginal costs for better nitrogen management inputs and reductions in the area of lower valued crops grown in the study areas. Despite the shortage of data on quantitative effects of improved nitrogen efficiency; our results demonstrate the potential of combining economic and agronomic data into a model that can reflect differences in cost and substitutabilty in nitrogen application methods, that can be used to reduce the quantity of nitrogen leaching into groundwater.

  3. Emissions from Combustion of Open Area Sources: Prescribed Forest and Agricultural Burns

    EPA Science Inventory

    Emissions from wildfires and prescribed forest and agricultural burns generate a variety of emissions that can cause adverse health effects for humans, contribute to climate change, and decrease visibility. Only limited pollutant data are available for these sources, particularly...

  4. Wetlands and Agriculture in Africa: Major Sources of N2O?

    NASA Astrophysics Data System (ADS)

    Gettel, G. M.

    2015-12-01

    Papyrus wetlands in East Africa are rapidly being converted to agricultural production in an effort to increase food security. This conversion is often seasonal, with wetlands being used for grazing and crop production of maize, sugarcane, and rice during dry seasons, and flooding occurring during wet seasons. An important question with respect to greenhouse gas production is whether wetland conversion to agriculture increases N2O fluxes. This trend has been shown in temperate regions where increased N2O fluxes are positively related to low soil C:N ratios, especially when soil moisture content remains high. In order to examine whether denitrification contributes to N2O flux, we measured potential denitrification rates (PDR by acetylene block method) in intact papyrus wetlands and agricultural converted wetlands in Kenya, Tanzania, Uganda, and Rwanda, and also performed multivariate analysis to relate soil characteristics to PDR. Agricultural land-cover types included maize, sugarcane, rice, and grazing. Results showed that intact wetlands are potentially important sources of N2O, as PDR in papyrus vegetation were consistently the highest (p<0.05; 128 - 601 μg N2O g DW-1 hour-1) while grazing sites showed the lowest (0.1 - 0.5 μg N2O g DW-1 hour-1). Rates were second highest in rice fields (2.3 - 303 μg N2O g DW-1 hour-1), and intermediate in maize and sugarcane (6.5 - 75 μmg N2O g DW-1 hour-1 and 5 - 30 μg N2O g DW-1 hour-1 respectively). PDR across all sites was inversely related to soil C:N ratio, with nitrate consistently limiting PDR in the wetland sites while soil carbon limited PDR in agricultural sites. This is seemingly in contrast with other findings that show that lower C:N ratios result in high N2O fluxes from drained wetland sites. However, flux measurements along with more realistic process-based measurements of denitrification are urgently needed to more fully understand the effect of agricultural conversion of wetlands in East Africa.

  5. 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

  6. Non-agricultural sources of groundwater nitrate: a review and case study.

    PubMed

    Wakida, Fernando T; Lerner, David N

    2005-01-01

    Nitrate is often seen as an agricultural pollutant of groundwater and so is expected to be at higher concentrations in the groundwaters surrounding a city than in those beneath it. However the difference between rural and urban nitrate concentrations is often small, due to the non-agricultural sources of nitrogen that are concentrated in cities. This paper illustrates the source and significance of non-agricultural nitrogen for groundwater and presents a case study of nitrate loading in the city of Nottingham. Major sources of nitrogen in urban aquifers are related to wastewater disposal (on-site systems and leaky sewers), solid waste disposal (landfills and waste tips). The major sources of nitrogen in the Nottingham area are mains leakage and contaminated land with approximately 38% each of a total load of 21 kg N ha(-1) year(-1).

  7. Research Orientations and Sources of Influence: Agricultural Scientists in the U.S. Land-Grant System.

    ERIC Educational Resources Information Center

    Goldberger, Jessica R.

    2001-01-01

    Uses data from a 1995-96 national survey of agricultural scientists at land-grant universities to investigate the relative importance of 19 sources of influence on agricultural scientists engaged in six areas of agricultural research: productionist-oriented, sustainable agriculture, environmental, basic, consumer-oriented, and rural…

  8. Re-examining the basis for source discrimination and data corrections used by sediment fingerprinting studies in agricultural catchments

    NASA Astrophysics Data System (ADS)

    Smith, Hugh; Blake, Will

    2014-05-01

    The sediment fingerprinting technique has been widely used in agricultural catchments to quantify fine sediment contributions from various land use sources. This application of the technique depends on the key assumption that land-use source signatures imprinted on catchment soils are decipherable from those due to other landscape factors affecting soil and sediment properties. We re-examine this key assumption by investigating (i) the physical and chemical basis for source discrimination and (ii) potential factors that may confound source un-mixing in agricultural catchments, including particle size and organic matter effects on tracer properties. The study is situated in the River Tamar, a predominantly agricultural catchment in south-west England that has also been affected by mining. Source discrimination focused on pasture and cultivated land uses and channel banks. Monthly, time-integrated suspended sediment samples were collected across seven catchments for a 12-month period. Physical and chemical properties measured in source soils and sediment included fallout radionuclides, major and minor element geochemical constituents, total organic carbon and particle size. Source discrimination was entirely dependent on differences in tracer property concentrations between surface and sub-surface soils. This is based on fallout radionuclide concentrations that are surface-elevated, while many geochemical properties are surface-depleted due to weathering and pedogenetic effects, although surface soil contamination can reverse this trend. Source discrimination in the study catchments was limited by (i) rotation of cultivated and pasture fields resulting in reduced differences between these two sources and (ii) the cultivated source signature resembling a mix of the pasture and channel bank sources for many tracer properties. Furthermore, metal pollution from abandoned historic mines and organic enrichment of sediment from areas of peaty soil resulted in the non

  9. Financing alternatives for agricultural nonpoint source pollution control programs. Final report

    SciTech Connect

    Braden, J.B.; Farnsworth, R.L.; Seitz, W.D.; Uchtmann, D.L.

    1988-10-01

    The study examines mechanisms for increasing state and local spending for abatement of nonpoint source pollution from agriculture. Emphasis is on the legal feasibility and economic consequences of various funding options. The state and local funding mechanisms considered include income or sales taxes, an income tax checkoff, property taxes, special property assessments, water taxes, recreation license fees or surcharges, recreational equipment and fuel excise taxes, recreational access fees, erosion taxes, and farm chemicals taxes. Rated most highly are: property taxes or special assessments and water taxes at the local level; and water taxes and increased recreation fees at the state level. These mechanisms have a clear connection to the objective of improved water quality, would yield substantial revenues, and would be easy to administer. The remaining funding mechanisms would be too difficult to administer or have limited revenue potential.

  10. Interrelationships between Mass Media Use and Interpersonal Source Use in Agricultural Development: The Case of the Dominican Republic.

    ERIC Educational Resources Information Center

    Abbott, Eric A.; de Leon, Cesar Amado Martinez

    A study examined (1) how the use of interpersonal information sources, the use of print media sources, and the use of radio sources are interrelated for agricultural decisions, and (2) which patterns of media use or interpersonal source use are most closely associated with knowing recommendations made by agricultural extension services and with…

  11. Catalog of infrared observations including: Bibliography of infrared astronomy and index of infrared source positions

    NASA Technical Reports Server (NTRS)

    Gezari, D. Y.; Schmitz, M.; Mead, J. M.

    1984-01-01

    The Catalog of Infrared Observations and its Far Infrared Supplement summarize all infrared astronomical observations at infrared wavelengths published in the scientific literature between 1965 and 1982. The Catalog includes as appendices the Bibliography of infrared astronomy which keys observations in the Catalog with the original journal references, and the index of infrared source positions which gives source positions for alphabetically listed sources in the Catalog. The Catalog data base contains over 85,000 observations of about 10,000 infrared sources, of which about 2,000 have no known visible counterpart.

  12. Horse paddocks - an emerging source of agricultural water pollution

    NASA Astrophysics Data System (ADS)

    Masud Parvage, Mohammed; Ulén, Barbro; Kirchmann, Holger

    2015-04-01

    Horse farms occupy about 4% of the total agricultural land in the EU but are not well investigated with regard to their impact on water quality. Horse paddocks commonly hold horses on a limited space and the animal density often exceeds the recommended density. Therefore, paddock soils receive significant amounts of phosphorus (P) and nitrogen (N) through feed residues and deposition of faeces and urine, which can lead to nutrient build-up in the soil and subsequent losses to aquatic systems. This study characterized the potential risk of phosphorus (P) and nitrogen (N) leaching losses from Swedish horse paddocks through three stage examination of soil and water P and N status. The experiment began with a pilot study where surface soil P status and eight years of drainage P data were examined from a paddock catchment and an adjacent arable catchment both receiving similar amount of P and N over years. Results showed that there were no signi?cant differences in water-soluble P (WSP) or total P data in soils but the drainage water P concentrations, being higher in the paddock catchment (0.33 mg P l-1, mainly in dissolved reactive form) than the arable catchment (0.10 mg P l-1). In the second experiment, soil P and N status were examined in different parts of horse paddocks (feeding, grazing, and excretion areas) to identify existence of any potential hotspots for losses within the paddock. In total, seven horse farms, covering different grazing densities and soil textures representative of Swedish horse paddocks were examined. The results showed that concentrations of WSP, plant available P or P-AL (P extracted in ammonium acetate lactate solution at pH 3.75), and total N were highest in feeding and excretion areas within the paddocks. It was also observed that the WSP concentration in the paddocks was strongly correlated with horse density (R2 = 0.80, p < 0.001) and P-AL with years of paddock management (R2 = 0.78, p < 0.001). In the final experiment, topsoil

  13. Potential pollutant sources in a Choptank River subwatershed: Influence of agricultural and residential land use and aqueous and atmospheric sources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture and animal feeding operations have been implicated as sources of water pollution along the Choptank River, an estuary and tributary of the Chesapeake Bay. This study examined a subwatershed within the Choptank River watershed for effects of land use on water quality. Water and sediment...

  14. Agricultural non-point source pollution in China: causes and mitigation measures.

    PubMed

    Sun, Bo; Zhang, Linxiu; Yang, Linzhang; Zhang, Fusuo; Norse, David; Zhu, Zhaoliang

    2012-06-01

    Non-point source (NPS) pollution has been increasingly serious in China since the 1990s. The increases of agricultural NPS pollution in China is evaluated for the period 2000-2008 by surveying the literature on water and soil pollution from fertilizers and pesticides, and assessing the surplus nitrogen balance within provinces. The main causes for NPS pollution were excessive inputs of nitrogen fertilizer and pesticides, which were partly the result of the inadequate agricultural extension services and the rapid expansion of intensive livestock production with little of waste management. The annual application of synthetic nitrogen fertilizers and pesticides in China increased by 50.7 and 119.7%, respectively, during 1991-2008. The mitigation measures to reduce NPS pollution include: correct distortion in fertilizer prices; improve incentives for the recycling of organic manure; provide farmers with better information on the sound use of agro-chemicals; and tighten the regulations and national standards on organic waste disposal and pesticides use.

  15. Agroforestry buffers for nonpoint source pollution reductions from agricultural watersheds.

    PubMed

    Udawatta, Ranjith P; Garrett, Harold E; Kallenbach, Robert

    2011-01-01

    Despite increased attention and demand for the adoption of agroforestry practices throughout the world, rigorous long-term scientific studies confirming environmental benefits from the use of agroforestry practices are limited. The objective was to examine nonpoint-source pollution (NPSP) reduction as influenced by agroforestry buffers in watersheds under grazing and row crop management. The grazing study consists of six watersheds in the Central Mississippi Valley wooded slopes and the row crop study site consists of three watersheds in a paired watershed design in Central Claypan areas. Runoff water samples were analyzed for sediment, total nitrogen (TN), and total phosphorus (TP) for the 2004 to 2008 period. Results indicate that agroforestry and grass buffers on grazed and row crop management sites significantly reduce runoff, sediment, TN, and TP losses to streams. Buffers in association with grazing and row crop management reduced runoff by 49 and 19%, respectively, during the study period as compared with respective control treatments. Average sediment loss for grazing and row crop management systems was 13.8 and 17.9 kg ha yr, respectively. On average, grass and agroforestry buffers reduced sediment, TN, and TP losses by 32, 42, and 46% compared with the control treatments. Buffers were more effective in the grazing management practice than row crop management practice. These differences could in part be attributed to the differences in soils, management, and landscape features. Results from this study strongly indicate that agroforestry and grass buffers can be designed to improve water quality while minimizing the amount of land taken out of production.

  16. Agricultural Libraries and Information.

    ERIC Educational Resources Information Center

    Russell, Keith W., Ed.; Pisa, Maria G., Ed.

    1990-01-01

    Eleven articles address issues relating to agricultural libraries and information, including background on agricultural libraries and information, trend management, document delivery, reference services, user needs and library services, collection development, technologies for international information management, information sources,…

  17. Landscape planning for agricultural nonpoint source pollution reduction III: Assessing phosphorus and sediment reduction potential

    USGS Publications Warehouse

    Diebel, M.W.; Maxted, J.T.; Robertson, D.M.; Han, S.; Vander Zanden, M. J.

    2009-01-01

    Riparian buffers have the potential to improve stream water quality in agricultural landscapes. This potential may vary in response to landscape characteristics such as soils, topography, land use, and human activities, including legacies of historical land management. We built a predictive model to estimate the sediment and phosphorus load reduction that should be achievable following the implementation of riparian buffers; then we estimated load reduction potential for a set of 1598 watersheds (average 54 km2) in Wisconsin. Our results indicate that land cover is generally the most important driver of constituent loads in Wisconsin streams, but its influence varies among pollutants and according to the scale at which it is measured. Physiographic (drainage density) variation also influenced sediment and phosphorus loads. The effect of historical land use on present-day channel erosion and variation in soil texture are the most important sources of phosphorus and sediment that riparian buffers cannot attenuate. However, in most watersheds, a large proportion (approximately 70%) of these pollutants can be eliminated from streams with buffers. Cumulative frequency distributions of load reduction potential indicate that targeting pollution reduction in the highest 10% of Wisconsin watersheds would reduce total phosphorus and sediment loads in the entire state by approximately 20%. These results support our approach of geographically targeting nonpoint source pollution reduction at multiple scales, including the watershed scale. ?? 2008 Springer Science+Business Media, LLC.

  18. Landscape planning for agricultural nonpoint source pollution reduction III: assessing phosphorus and sediment reduction potential.

    PubMed

    Diebel, Matthew W; Maxted, Jeffrey T; Robertson, Dale M; Han, Seungbong; Vander Zanden, M Jake

    2009-01-01

    Riparian buffers have the potential to improve stream water quality in agricultural landscapes. This potential may vary in response to landscape characteristics such as soils, topography, land use, and human activities, including legacies of historical land management. We built a predictive model to estimate the sediment and phosphorus load reduction that should be achievable following the implementation of riparian buffers; then we estimated load reduction potential for a set of 1598 watersheds (average 54 km(2)) in Wisconsin. Our results indicate that land cover is generally the most important driver of constituent loads in Wisconsin streams, but its influence varies among pollutants and according to the scale at which it is measured. Physiographic (drainage density) variation also influenced sediment and phosphorus loads. The effect of historical land use on present-day channel erosion and variation in soil texture are the most important sources of phosphorus and sediment that riparian buffers cannot attenuate. However, in most watersheds, a large proportion (approximately 70%) of these pollutants can be eliminated from streams with buffers. Cumulative frequency distributions of load reduction potential indicate that targeting pollution reduction in the highest 10% of Wisconsin watersheds would reduce total phosphorus and sediment loads in the entire state by approximately 20%. These results support our approach of geographically targeting nonpoint source pollution reduction at multiple scales, including the watershed scale.

  19. Investigation of the effectiveness of source control sanitation concepts including pre-treatment with Rottebehaelter.

    PubMed

    Gajurel, D R; Li, Z; Otterpohl, R

    2003-01-01

    High levels of nutrients recovery can be achieved with source control sanitation--technologies are already available. Separation toilets for example separate urine that can be used in agriculture with some crop restrictions as a fertiliser after about 6 months of storage. The grey water has very low loads of nitrogen and can be treated in different combinations of biological and physical treatment and reused. Faecal matter with flush water from the separation toilet can be discharged into Rottebehaelter (an underground pre-composting tank) that retains solid material and drains liquid to a certain extent. Investigation of Rottebehaelter in the different sites and laboratory experiments showed that retained faecal material still contained a high percentage of water. However, odour was not noticed in those Rottebehaelters that have been examined. One of the major advantages of this system over other forms of pre-treatment as the septic tanks is that it does not deprive agriculture of the valuable nutrients and soil conditioner from human excreta. It has to be stated that maintenance is a crucial factor. As an intermediate result of the intensive research of Rottebehaelter it seems that these systems are rather a way of solids retaining, de-watering and long-term storage before the contents are further treated.

  20. Sources of fine sediment stored in agricultural lowland streams, Midwest, USA

    NASA Astrophysics Data System (ADS)

    Lamba, Jasmeet; Thompson, A. M.; Karthikeyan, K. G.; Fitzpatrick, Faith A.

    2015-05-01

    Agricultural activities can accelerate the offsite transport of productive soil from fields leading to stream water quality degradation. Identification of the nature and relative contribution of different sources to fine-grained sediment (e.g., silts, clays) in streams is important to effectively focus agricultural best management practices in watersheds. Sediment fingerprinting techniques through the use of geochemical tracers are commonly used to differentiate relative contribution from various sources. Research was conducted in lowland streams in the Pleasant Valley watershed in South Central Wisconsin (USA) to identify provenance of fine-grained sediment deposits and evaluate the impact of land use on relative contributions from the following potential sources: cropland, pasture, woodland, and eroding stream banks. Results show that both agriculture (croplands and pastures) and eroding stream banks are primary sources to fine sediment deposits on the stream bed with contributions ranging from 19 to 100% and 0 to 81%, respectively. The increase in area under agricultural land use within a subwatershed results in greater contribution from agriculture (R2 = 0.846, p = 0.0034). Relative contributions from eroding stream banks increased with increasing area under grasslands and woodlands within a subwatershed (R2 = 0.814, p = 0.0055). Subwatersheds with greater mass of fine sediment deposited on the stream bed per unit area should be prioritized for best management practices. The conservation practices should be targeted to stream banks or croplands depending on the dominant source of fine sediment within a subwatershed. Site specific changes in relative contributions from different sources to fine-grained sediment in this watershed highlights the complexities involved in sediment transport dynamics. The nested sampling sites helped determine that sediment dynamics at the subwatershed scale need to be considered for application of targeted conservation techniques.

  1. How Do Washington's Newspaper Editors Evaluate Their Sources of Agricultural News?--A Survey.

    ERIC Educational Resources Information Center

    Sampson, M. W.

    This report presents the results of a questionnaire sent to the daily and weekly newspaper editors in Washington to evaluate their sources of agricultural news. Responses were obtained from 16 of 21 daily newspaper editors queried and 63 of 140 weekly editors. The questionnaire was designed to check the accuracy of newspapers' mailing addresses,…

  2. Severe situation of rural nonpoint source pollution and efficient utilization of agricultural wastes in the Three Gorges Reservoir Area.

    PubMed

    Zhang, Tong; Ni, Jiupai; Xie, Deti

    2015-11-01

    Rural nonpoint source (NPS) pollution caused by agricultural wastes has become increasingly serious in the Three Gorges Reservoir Area (TGRA), significantly affecting the reservoir water quality. The grim situation of rural NPS pollution in the TGRA indicated that agrochemicals (chemical fertilizer and pesticide) were currently the highest contributor of rural NPS pollution (50.38%). The harmless disposal rates of livestock excrement, crop straws, rural domestic refuse, and sewage also cause severe water pollution. More importantly, the backward agricultural economy and the poor environmental awareness of farmers in the hinterland of the TGRA contribute to high levels of rural NPS pollution. Over the past decade, researchers and the local people have carried out various successful studies and practices to realize the effective control of rural NPS pollution by efficiently utilizing agricultural wastes in the TGRA, including agricultural waste biogas-oriented utilization, crop straw gasification, decentralized land treatment of livestock excrement technology, and crop straw modification. These technologies have greatly increased the renewable resource utilization of agricultural wastes and improved water quality and ecological environment in the TGRA. PMID:26392092

  3. Severe situation of rural nonpoint source pollution and efficient utilization of agricultural wastes in the Three Gorges Reservoir Area.

    PubMed

    Zhang, Tong; Ni, Jiupai; Xie, Deti

    2015-11-01

    Rural nonpoint source (NPS) pollution caused by agricultural wastes has become increasingly serious in the Three Gorges Reservoir Area (TGRA), significantly affecting the reservoir water quality. The grim situation of rural NPS pollution in the TGRA indicated that agrochemicals (chemical fertilizer and pesticide) were currently the highest contributor of rural NPS pollution (50.38%). The harmless disposal rates of livestock excrement, crop straws, rural domestic refuse, and sewage also cause severe water pollution. More importantly, the backward agricultural economy and the poor environmental awareness of farmers in the hinterland of the TGRA contribute to high levels of rural NPS pollution. Over the past decade, researchers and the local people have carried out various successful studies and practices to realize the effective control of rural NPS pollution by efficiently utilizing agricultural wastes in the TGRA, including agricultural waste biogas-oriented utilization, crop straw gasification, decentralized land treatment of livestock excrement technology, and crop straw modification. These technologies have greatly increased the renewable resource utilization of agricultural wastes and improved water quality and ecological environment in the TGRA.

  4. 13 CFR 120.102 - Funds not available from alternative sources, including personal resources of principals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Funds not available from alternative sources, including personal resources of principals. 120.102 Section 120.102 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Policies Applying to All Business Loans...

  5. 13 CFR 120.102 - Funds not available from alternative sources, including personal resources of principals.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false Funds not available from alternative sources, including personal resources of principals. 120.102 Section 120.102 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Policies Applying to All Business Loans...

  6. 77 FR 6463 - Revisions to Labeling Requirements for Blood and Blood Components, Including Source Plasma...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-08

    ... 20993-0002, (301) 796-9148. SUPPLEMENTARY INFORMATION: In the FR Doc. 2011-33554, appearing on page 7 in the Federal Register of Tuesday, January 3, 2012 (77 FR 7), the following correction is made: 1. On... Requirements for Blood and Blood Components, Including Source Plasma; Correction AGENCY: Food and...

  7. Concentrations, distribution, sources, and ecological risk assessment of heavy metals in agricultural topsoil of the Three Gorges Dam region, China.

    PubMed

    Liu, Minxia; Yang, Yuyi; Yun, Xiaoyan; Zhang, Miaomiao; Wang, Jun

    2015-03-01

    Concentrations, distribution, sources, and ecological risk of seven heavy metals including chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd), and mercury (Hg) in agricultural topsoil samples of the Three Gorges Dam region, China were investigated in this study. Among seven heavy metals, Zn had the highest mean concentration (149 mg kg(-1)) in the agricultural topsoil, followed by Cr (66 mg kg(-1)), Cu (52.2 mg kg(-1)), Pb (13.0 mg kg(-1)), Ni (8.5 mg kg(-1)), Cd (0.29 mg kg(-1)), and Hg (0.08 mg kg(-1)). Enrichment factor (EF) values of Zn, Cu, Cd, and Hg were higher than 1.5, indicating that Zn, Cu, Cd, and Hg were the major pollutants in this study area. The average potential ecological risk index (RI) value was 147, suggesting that heavy metals in the agricultural topsoil in the study area had a low ecological risk. The result of factor analysis (FA) and correlation analysis showed that long-term use of chemical fertilizer and pesticides, natural rock weathering, and atmospheric deposition were the several main sources of seven heavy metals in agricultural topsoil of the Three Gorges Dam region. Factor analysis-multiple linear regression (FA-MLR) results indicated that the most important source in this area was long-term use of chemical fertilizer and pesticides, which contributed 70 % for Cu and Zn, 62 % for Cd, and 72 % for Hg. More attention must be paid to the extensive use of chemical fertilizers and pesticides containing heavy metals which have been accumulated in the agricultural soil. PMID:25716527

  8. Concentrations, distribution, sources, and ecological risk assessment of heavy metals in agricultural topsoil of the Three Gorges Dam region, China.

    PubMed

    Liu, Minxia; Yang, Yuyi; Yun, Xiaoyan; Zhang, Miaomiao; Wang, Jun

    2015-03-01

    Concentrations, distribution, sources, and ecological risk of seven heavy metals including chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd), and mercury (Hg) in agricultural topsoil samples of the Three Gorges Dam region, China were investigated in this study. Among seven heavy metals, Zn had the highest mean concentration (149 mg kg(-1)) in the agricultural topsoil, followed by Cr (66 mg kg(-1)), Cu (52.2 mg kg(-1)), Pb (13.0 mg kg(-1)), Ni (8.5 mg kg(-1)), Cd (0.29 mg kg(-1)), and Hg (0.08 mg kg(-1)). Enrichment factor (EF) values of Zn, Cu, Cd, and Hg were higher than 1.5, indicating that Zn, Cu, Cd, and Hg were the major pollutants in this study area. The average potential ecological risk index (RI) value was 147, suggesting that heavy metals in the agricultural topsoil in the study area had a low ecological risk. The result of factor analysis (FA) and correlation analysis showed that long-term use of chemical fertilizer and pesticides, natural rock weathering, and atmospheric deposition were the several main sources of seven heavy metals in agricultural topsoil of the Three Gorges Dam region. Factor analysis-multiple linear regression (FA-MLR) results indicated that the most important source in this area was long-term use of chemical fertilizer and pesticides, which contributed 70 % for Cu and Zn, 62 % for Cd, and 72 % for Hg. More attention must be paid to the extensive use of chemical fertilizers and pesticides containing heavy metals which have been accumulated in the agricultural soil.

  9. GCAM 3.0 Agriculture and Land Use: Data Sources and Methods

    SciTech Connect

    Kyle, G. Page; Luckow, Patrick; Calvin, Katherine V.; Emanuel, William R.; Nathan, Mayda; Zhou, Yuyu

    2011-12-12

    This report presents the data processing methods used in the GCAM 3.0 agriculture and land use component, starting from all source data used, and detailing all calculations and assumptions made in generating the model inputs. The report starts with a brief introduction to modeling of agriculture and land use in GCAM 3.0, and then provides documentation of the data and methods used for generating the base-year dataset and future scenario parameters assumed in the model input files. Specifically, the report addresses primary commodity production, secondary (animal) commodity production, disposition of commodities, land allocation, land carbon contents, and land values.

  10. Investigating the sources of sediment in a Canadian agricultural watershed using a colour-based fingerprinting technique

    NASA Astrophysics Data System (ADS)

    Barthod, Louise; Lobb, David; Owens, Philip; Martinez-Carreras, Nuria; Koiter, Alexander; Petticrew, Ellen; McCullough, Gregory

    2014-05-01

    The development of beneficial management practises to minimize adverse impacts of agriculture on soil and water quality requires information on the sources of sediment at the watershed scale. Sediment fingerprinting allows for the determination of sediment sources and apportionment of their contribution within a watershed, using unique physical, radiochemical or biogeochemical properties, or fingerprints, of the potential sediment sources. The use of sediment colour as a fingerprint is an emerging technique that can provide a rapid and inexpensive means of investigating sediment sources. This technique is currently being utilized to determine sediment sources within the South Tobacco Creek Watershed, an agricultural watershed located in the Canadian prairies (south-central Manitoba). Suspended sediment and potential source (topsoil, channel bank and shale bedrock material) samples were collected between 2009 and 2011 at six locations along the main stem of the creek. Sample colour was quantified from diffuse reflectance spectrometry measurements over the visible wavelength range using a spectroradiometer (ASD Field Spec Pro, 400-2500 nm). Sixteen colour coefficients were derived from several colour space models (CIE XYZ, CIE xyY, CIE Lab, CIE Luv, CIE Lch, Landsat RGB, Redness Index). The individual discrimination power of the colour coefficients, after passing several prerequisite tests (e.g., linearly additive behaviour), was assessed using discriminant function analysis. A stepwise discriminant analysis, based on the Wilk's lambda criterion, was then performed in order to determine the best-suited colour coefficient fingerprints which maximized the discrimination between the potential sources. The selected fingerprints classified the source samples in the correct category 86% of the time. The misclassification is due to intra-source variability and source overlap which can lead to higher uncertainty in sediment source apportionment. The selected fingerprints

  11. Active control of environmental noise, VIII: increasing the response to primary source changes including unpredictable noise

    NASA Astrophysics Data System (ADS)

    Wright, S. E.; Atmoko, H.; Vuksanovic, B.

    2004-07-01

    Conventional adaptive cancellation systems using traditional transverse finite impulse response (FIR) filters, together with least mean square (LMS) adaptive algorithms, well known in active noise control, are slow to adapt to primary source changes. This makes them inappropriate for cancelling rapidly changing noise, including unpredictable noise such as speech and music. Secondly, the cancelling structures require considerable computational processing effort to adapt to primary source and plant changes, particularly for multi-channel systems. This paper describes methods to increase the adaptive speed to primary source changes in large enclosed spaces and outdoor environments. A method is described that increases the response to time varying periodic noise using traditional transverse FIR filters. Here a multi-passband filter, with individual variable adaptive step sizes for each passband is automatically adjusted according to the signal level in each band. This creates a similar adaptive response for all frequencies within the total pass-band, irrespective of amplitude, minimizing the signal distortion and increasing the combined adaptive speed. Unfortunately, there is a limit to the adaptive speed using the above method as classical transverse FIR filters have a finite adaptive speed given by the stability band zero bandwidth. For rapidly changing periodic noise and unpredictable non-stationary noise, a rapid to instantaneous response is required. In this case the on-line adaptive FIR filters are dispensed with and replaced by a time domain solution that gives virtually instantaneous cancellation response (infinite adaptive speed) to primary source changes, and is computationally efficient.

  12. PROFILE: Comparative Analysis of New Zealand and US Approaches for Agricultural Nonpoint Source Pollution Management.

    PubMed

    Caruso

    2000-01-01

    / Nonpoint source (NPS) pollution from widespread agricultural/pastoral land use in New Zealand can result in receiving water quality problems, but the Resource Management Act of 1991 requires the sustainable management of land and water resources. Many similar types of problems occur in the United States, where the Clean Water Act is the primary legislation addressing NPS pollution and progress has been made on the development and use of a variety of management approaches. However, little evaluation and comparison of approaches or cooperation between the two countries has occurred in the past. This type of analysis could provide information that is useful for more effective management of the problem. The goal of this study is to evaluate and compare approaches used in New Zealand and the United States for management of agricultural NPS pollution.The role of the central government in New Zealand is generally limited to research and policy development, and regional councils are responsible for most monitoring and management of the problem. The role of the federal government in the United States includes research and monitoring, policy development, and regulation. States also have a significant management role. Both countries rely on voluntary approaches for NPS pollution management. Very few national water quality standards exist in New Zealand, whereas standards are widely used in the United States. Loading estimates and modeling are often used in the United States, but not in New Zealand. A wide range of best management practices (BMPs) are used in the United States, including buffer strips and constructed/engineered wetlands. Buffer strips and riparian management have been emphasized and used widely in New Zealand.Many approaches are common to both countries, but management of the problem has only been partly successful. The primary barriers are the inadequacy of the voluntary approach and the lack of scientific tools that are useful to decision-makers. More work

  13. Reducing fluxes of faecal indicator compliance parameters to bathing waters from diffuse agricultural sources: the Brighouse Bay study, Scotland.

    PubMed

    Kay, D; Aitken, M; Crowther, J; Dickson, I; Edwards, A C; Francis, C; Hopkins, M; Jeffrey, W; Kay, C; McDonald, A T; McDonald, D; Stapleton, C M; Watkins, J; Wilkinson, J; Wyer, M D

    2007-05-01

    The European Water Framework Directive requires the integrated management of point and diffuse pollution to achieve 'good' water quality in 'protected areas'. These include bathing waters, which are regulated using faecal indicator organisms as compliance parameters. Thus, for the first time, European regulators are faced with the control of faecal indicator fluxes from agricultural sources where these impact on bathing water compliance locations. Concurrently, reforms to the European Union (EU) Common Agricultural Policy offer scope for supporting on-farm measures producing environmental benefits through the new 'single farm payments' and the concept of 'cross-compliance'. This paper reports the first UK study involving remedial measures, principally stream bank fencing, designed to reduce faecal indicator fluxes at the catchment scale. Considerable reduction in faecal indicator flux was observed, but this was insufficient to ensure bathing water compliance with either Directive 76/160/EEC standards or new health-evidence-based criteria proposed by WHO and the European Commission.

  14. Landscape planning for agricultural nonpoint source pollution reduction I: a geographical allocation framework.

    PubMed

    Diebel, Matthew W; Maxted, Jeffrey T; Nowak, Peter J; Vander Zanden, M Jake

    2008-11-01

    Agricultural nonpoint source pollution remains a persistent environmental problem, despite the large amount of money that has been spent on its abatement. At local scales, agricultural best management practices (BMPs) have been shown to be effective at reducing nutrient and sediment inputs to surface waters. However, these effects have rarely been found to act in concert to produce measurable, broad-scale improvements in water quality. We investigated potential causes for this failure through an effort to develop recommendations for the use of riparian buffers in addressing nonpoint source pollution in Wisconsin. We used frequency distributions of phosphorus pollution at two spatial scales (watershed and field), along with typical stream phosphorus (P) concentration variability, to simulate benefit/cost curves for four approaches to geographically allocating conservation effort. The approaches differ in two ways: (1) whether effort is aggregated within certain watersheds or distributed without regard to watershed boundaries (dispersed), and (2) whether effort is targeted toward the most highly P-polluting fields or is distributed randomly with regard to field-scale P pollution levels. In realistic implementation scenarios, the aggregated and targeted approach most efficiently improves water quality. For example, with effort on only 10% of a model landscape, 26% of the total P load is retained and 25% of watersheds significantly improve. Our results indicate that agricultural conservation can be more efficient if it accounts for the uneven spatial distribution of potential pollution sources and the cumulative aspects of environmental benefits.

  15. Identification of nitrogen sources to four small lakes in the agricultural region of Khorezm, Uzbekistan

    USGS Publications Warehouse

    Shanafield, M.; Rosen, M.; Saito, L.; Chandra, S.; Lamers, J.; Nishonov, Bakhriddin

    2010-01-01

    Pollution of inland waters by agricultural land use is a concern in many areas of the world, and especially in arid regions, where water resources are inherently scarce. This study used physical and chemical water quality and stable nitrogen isotope (δ15N) measurements from zooplankton to examine nitrogen (N) sources and concentrations in four small lakes of Khorezm, Uzbekistan, an arid, highly agricultural region, which is part of the environmentally-impacted Aral Sea Basin. During the 2-year study period, ammonium concentrations were the highest dissolved inorganic N species in all lakes, with a maximum of 3.00 mg N l−1 and an average concentration of 0.62 mg N l−1. Nitrate levels were low, with a maximum concentration of 0.46 mg N l−1 and an average of 0.05 mg N l−1 for all four lakes. The limited zooplankton δ15N values did not correlate with the high loads of synthetic fertilizer applied to local croplands during summer months. These results suggest that the N cycles in these lakes may be more influenced by regional dynamics than agricultural activity in the immediate surroundings. The Amu-Darya River, which provides the main source of irrigation water to the region, was identified as a possible source of the primary N input to the lakes.

  16. U and Sr Isotope Tracers of Agricultural Salinity Sources to the Lower Rio Grande River

    NASA Astrophysics Data System (ADS)

    Nyachoti, S. K.; Ma, L.; Szynkiewicz, A.; Jin, L.; McIntosh, J. C.

    2014-12-01

    Elevated salinity of the lower Rio Grande River deteriorates water quality and limits domestic and agricultural water use. Both natural and anthropogenic processes contribute salts in the Rio Grande. Previous studies have focused on natural salt contributions with less emphasis on anthropogenic sources of salinity in the Rio Grande. Using (234U/238U) activity ratios (UAR), 87Sr/86Sr isotope ratios, and major element concentrations, we aim to trace and quantify the salt loads in the Lower Rio Grande watershed which is greatly impacted by agricultural activities. Between 2009 and 2010, we sampled the Rio Grande stretch and irrigation return flows between the Elephant Butte Reservoir, New Mexico and El Paso, Texas. Furthermore, we monitored in monthly intervals the temporal changes of chemical and isotopic compositions of the Rio Grande at Canutillo, Tx. Our results show higher U and Sr fluxes in the Rio Grande during the irrigation season as compared to the non-irrigation season. The UAR (1.62 to 2.13) and 87Sr/86Sr ratios (0.7099 to 0.7138) were higher in the non-irrigation season compared to the irrigation season (UAR: 1.69 to 1.77; 87Sr/86Sr: 0.7100 to 0.7106). These variations of UAR and 87Sr/86Sr ratios imply multiple sources of U and Sr in the Rio Grande. In contrast, the agricultural return flows show a narrow range of UAR (1.31 to 1.37) and 87Sr/86Sr ratios (0.7091 to 0.7099) in the studied seasons. This is consistent with salinity contributions from agricultural sources. Rio Grande at Canutillo shows low UAR (1.62 to 1.77) and 87Sr/86Sr ratios (0.7104 to 0.7105) during the irrigation season as compared to the non-irrigation season (UAR: 2.04 to 2.24; 87Sr/86Sr: 0.7105 to 0.7109). The low U and Sr signature at Canutillo during the irrigation season is close to that of the agricultural return flows, indicative of agricultural salinity sources. These results provide useful elemental and isotopic constraints for future mass balance calculations of salinity

  17. Agricultural sources of contaminants of emerging concern and adverse health effects on freshwater fish

    USGS Publications Warehouse

    Tillitt, Donald E.; Buxton, Herbert T.

    2011-01-01

    Agricultural contaminants of emerging concern (CECs) are generally thought of as certain classes of chemicals associated with animal feeding and production facilities. Veterinary pharmaceuticals used in animal food production systems represent one of the largest groups of CECs. In our review, we discuss the extensive increase in use of antibiotics in animal feeding operations (AFOs) around the world. AFOs are a major consumer of antibiotics and other veterinary pharmaceuticals and over the past decade there has been growing information on the occurrence, release, and fate of CECs from animal food production operations, including the application of pharmaceutical-containing manure to agricultural fields and releases from waste lagoons. Concentrations of CECs in surface and ground water in proximity to AFOs correspond to their presence in the AFO wastes. In many cases, the environmental concentrations of agriculturally-derived CECs are below toxicity thresholds. Hormones and hormone replacement compounds are a notable exception, where chemical concentrations near AFOs can exceed concentrations known to cause adverse effects on endocrine-related functions in fish. In addition, some agricultural pesticides, once thought to be safe to non-target organisms, have demonstrated endocrine-related effects that may pose threats to fish populations in agricultural regions. That is, we have pesticides with emerging concerns, thus, the concern is emerging and not necessarily the chemical. In this light, one must consider certain agricultural pesticides to be included in the list of CECs. Even though agricultural pesticides are routinely evaluated in regulatory testing schemes which have been used for decades, the potential hazards of some pesticides have only recently been emerging. Emerging concerns of pesticides in fish include interference with hormone signaling pathways; additive (or more than additive) effects from pesticide mixtures; and adverse population-level effects at

  18. Contamination, source, and input route of polycyclic aromatic hydrocarbons in historic wastewater-irrigated agricultural soils.

    PubMed

    Wang, Ning; Li, Hong-Bo; Long, Jin-Lin; Cai, Chao; Dai, Jiu-Lan; Zhang, Juan; Wang, Ren-Qing

    2012-12-01

    Contamination by polycyclic aromatic hydrocarbons (PAHs) of historic wastewater-irrigated agricultural topsoil (0-5 cm) and the contribution of groundwater irrigation and atmospheric deposition to soil PAHs were studied in a typical agricultural region, i.e. Hunpu region, Liaoning, China. Concentrations of total PAHs ranged from 0.43 to 2.64 mg kg⁻¹ in topsoil, being lower than those found in other wastewater-irrigated areas. The levels of PAHs in soil declined as the distance from a water source increased. Concentrations of individual PAHs were generally higher in upland than in paddy topsoils. The calculated nemerow composite index showed that agricultural soil in the region was "polluted" by PAHs. A human health risk assessment based on the total toxic equivalent concentration showed that the presence of elevated concentrations of PAHs in the soil might pose a great threat to the health of local residents. Ratios of pairs of PAHs and principal component analysis (PCA) showed that pyrogenesis, such as coal combustion, was the main source of PAHs, while petroleum, to some extent, also had a strong influence on PAHs contamination in upland soil. The distribution patterns of individual PAHs and composition of PAHs differed between irrigation groundwater and topsoil, but were similar between atmospheric deposition and topsoil. There were significant linear correlations (r = 0.90; p < 0.01) between atmospheric deposition rates and average concentrations of the 16 individual PAHs in soils, while no significant relationships were observed between irrigation groundwater and topsoil in levels of PAHs. These suggested that PAHs in agricultural soils were mainly introduced from atmospheric deposition, rather than from groundwater irrigation after the phasing out of wastewater irrigation in the region since 2002. This study provides a reference to ensure agricultural product safety, pollution control, and proper soil management.

  19. Initial results of a full kinetic simulation of RF H- source including Coulomb collision process

    NASA Astrophysics Data System (ADS)

    Mochizuki, S.; Mattei, S.; Shibata, T.; Nishida, K.; Hatayama, A.; Lettry, J.

    2015-04-01

    In order to evaluate Electron Energy Distribution Function (EEDF) more correctly for radio frequency inductively coupled plasma (RF-ICP) in hydrogen negative ion sources, the Electromagnetic Particle-In-Cell (EM-PIC) simulation code has been improved by taking into account electron-electron Coulomb collision. Binary collision model is employed to model Coulomb collision process and we have successfully modeled it. The preliminary calculation including Coulomb collision has been done and it is shown that Coulomb collision doesn't have significant effects under the condition: electron density ne ˜ 1018 m-3 and high gas pressure pH2 = 3 Pa, while it is necessary to include Coulomb collision under high electron density and low gas pressure conditions.

  20. Including shielding effects in application of the TPCA method for detection of embedded radiation sources.

    SciTech Connect

    Johnson, William C.; Shokair, Isaac R.

    2011-12-01

    Conventional full spectrum gamma spectroscopic analysis has the objective of quantitative identification of all the radionuclides present in a measurement. For low-energy resolution detectors such as NaI, when photopeaks alone are not sufficient for complete isotopic identification, such analysis requires template spectra for all the radionuclides present in the measurement. When many radionuclides are present it is difficult to make the correct identification and this process often requires many attempts to obtain a statistically valid solution by highly skilled spectroscopists. A previous report investigated using the targeted principal component analysis method (TPCA) for detection of embedded sources for RPM applications. This method uses spatial/temporal information from multiple spectral measurements to test the hypothesis of the presence of a target spectrum of interest in these measurements without the need to identify all the other radionuclides present. The previous analysis showed that the TPCA method has significant potential for automated detection of target radionuclides of interest, but did not include the effects of shielding. This report complements the previous analysis by including the effects of spectral distortion due to shielding effects for the same problem of detection of embedded sources. Two examples, one with one target radionuclide and the other with two, show that the TPCA method can successfully detect shielded targets in the presence of many other radionuclides. The shielding parameters are determined as part of the optimization process using interpolation of library spectra that are defined on a 2D grid of atomic numbers and areal densities.

  1. Selection and application of agricultural wastes as solid carbon sources and biofilm carriers in MBR.

    PubMed

    Yang, Xiao-Li; Jiang, Qi; Song, Hai-Liang; Gu, Tian-Tian; Xia, Ming-Qian

    2015-01-01

    This paper examined the feasibility of agricultural wastes used as solid carbon sources and the effect of determined agricultural wastes on improving denitrification. Eight agricultural wastes were evaluated in MBR tests to find out their carbon release capacity, denitrification potential, leaching elements and surface properties. The results showed that retinervus luffae fructus, wheat straw, corncob and rice straw had higher carbon release capacity with COD of 13.17-21.07 mg g(-1)day(-1), BOD5 of 3.33-7.33 mg g(-1)day(-1) and respirable carbon of 8.64-10.71 mg g(-1)day(-1). Correspondingly, they displayed a good denitrification potential of 105.3-140.1mg NO3(-)-Ng(-1). Rice straw, retinervus luffae fructus and corncob were then applied in MBRs. These three agricultural wastes were found to be effective in enhancing the denitrification process, where the TN removal increased from 43.44% (control MBR) to 82.34, 68.92 and 62.97%, respectively.

  2. [Catchment scale risk assessment and critical source area identification of agricultural phosphorus loss].

    PubMed

    Li, Qi; Chen, Li-Ding; Qi, Xin; Zhang, Xin-Yu; Ma, Yan

    2007-09-01

    Agricultural non-point source phosphorus pollution is a severe problem for rural water bodies in China, but hard to control directly because of its special characteristics. In this paper, an approach on the catchment scale risk assessment and critical source area identification of agricultural phosphorus loss in northern China was made, based on the catchment scale phosphorus ranking scheme and the method proposed by Gburek et al. Eight factors were selected and weighed in the modified catchment scale phosphorus ranking scheme, and the phosphorus loss risk rating of each factor was adjusted based on the current professional standards and the actual circumstances in China. The areas with ' high' risk rating of phosphorus loss in definite catchment were the critical source areas for non-point source phosphorous pollution control in that catment. The availability of obtained data and the quantification of the assessment were taken into account in the new scheme, and GIS technique and geostatistics were used for confirming the factors. Therefore, the new scheme had definite operability and practicability. PMID:18062300

  3. Evaluating agricultural nonpoint-source pollution programs in two Lake Erie tributaries.

    PubMed

    Forster, D Lynn; Rausch, Jonathan N

    2002-01-01

    During the past three decades, numerous government programs have encouraged Lake Erie basin farmers to adopt practices that reduce water pollution. The first section of this paper summarizes these state and federal government agricultural pollution abatement programs in watersheds of two prominent Lake Erie tributaries, the Maumee River and Sandusky River. Expenditures are summarized for each program, total expenditures in each county are estimated, and cost effectiveness of program expenditures (i.e., cost per metric ton of soil saved) are analyzed. Farmers received nearly $143 million as incentive payments to implement agricultural nonpoint source pollution abatement programs in the Maumee and Sandusky River watersheds from 1987 to 1997. About 95% of these funds was from federal sources. On average, these payments totaled about $7000 per farm or about $30 per farm acre (annualized equivalent of $2 per acre) within the watersheds. Our analysis raises questions about how efficiently these incentive payments were allocated. The majority of Agricultural Conservation Program (ACP) funds appear to have been spent on less cost-effective practices. Also, geographic areas with relatively low (high) soil erosion rates received relatively large (small) funding.

  4. Salmonella source attribution based on microbial subtyping: does including data on food consumption matter?

    PubMed

    Mughini-Gras, Lapo; van Pelt, Wilfrid

    2014-11-17

    Source attribution based on microbial subtyping is being performed in many countries to ascertain the main reservoirs of human salmonellosis and to assess the impact of food safety interventions. To account for differences in exposure, the amount of food available for consumption within a country is often included in Salmonella source attribution models along with the level of contamination. However, not all foods have an equal probability of serving as vehicles for salmonellas, as some foods are more likely to be consumed raw/undercooked than others, posing a relatively higher risk. Using Salmonella data from the Netherlands in 2001-2004, this study aims at elucidating whether and how the incorporation of food consumption data in two source attribution models - the (modified) Dutch and Hald models - affects their attributions. We also propose the incorporation of an additional parameter to weight the amount of food consumed by its likelihood to be consumed raw/undercooked by the population. Incorporating the amount of food consumed caused a drastic change in the ranking of the top reservoirs in the Dutch model, but not in the Hald model, which proved to be insensitive to additional weightings given that its source-dependent factor can account for both food consumption and the ability for foods to serve as vehicles for salmonellas. Compared to attributions without food consumption, the Dutch model including the amount of food consumed showed an increase in the percentage of cases attributable to pigs and a decrease in that of layers/eggs, which became the second reservoir, after pigs. This was not consistent with established knowledge indicating that layers/eggs, rather than pigs, were the main reservoir of human salmonellosis in that period. By incorporating the additional weight reflecting the likelihood for different foods to be consumed raw/undercooked, the attributions of the Dutch model were effectively adjusted, both in terms of ranking and percent

  5. 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

  6. Modeling Agricultural Nonpoint Source Pollution Using a Geographic Information System Approach

    NASA Astrophysics Data System (ADS)

    Emili, Lisa A.; Greene, Richard P.

    2013-01-01

    Agricultural non-point source (NPS) pollution, primarily sediment and nutrients, is the leading source of water-quality impacts to surface waters in North America. The overall goal of this study was to develop geographic information system (GIS) protocols to facilitate the spatial and temporal modeling of changes in soils, hydrology, and land-cover change at the watershed scale. In the first part of this article, we describe the use of GIS to spatially integrate watershed scale data on soil erodibility, land use, and runoff for the assessment of potential source areas within an intensively agricultural watershed. The agricultural non-point source pollution (AGNPS) model was used in the Muddy Creek, Ontario, watershed to evaluate the effectiveness of management strategies in decreasing sediment and nutrient [phosphorus (P)] pollution. This analysis was accompanied by the measurement of water-quality parameters (dissolved oxygen, pH, hardness, alkalinity, and turbidity) as well as sediment and P loadings to the creek. Practices aimed at increasing year-round soil cover would be most effective in decreasing sediment and P losses in this watershed. In the second part of this article, we describe a method for characterizing land-cover change in a dynamic urban fringe watershed. The GIS method we developed for the Blackberry Creek, Illinois, watershed will allow us to better account for temporal changes in land use, specifically corn and soybean cover, on an annual basis and to improve on the modeling of watershed processes shown for the Muddy Creek watershed. Our model can be used at different levels of planning with minimal data preprocessing, easily accessible data, and adjustable output scales.

  7. Modeling agricultural nonpoint source pollution using a geographic information system approach.

    PubMed

    Emili, Lisa A; Greene, Richard P

    2013-01-01

    Agricultural non-point source (NPS) pollution, primarily sediment and nutrients, is the leading source of water-quality impacts to surface waters in North America. The overall goal of this study was to develop geographic information system (GIS) protocols to facilitate the spatial and temporal modeling of changes in soils, hydrology, and land-cover change at the watershed scale. In the first part of this article, we describe the use of GIS to spatially integrate watershed scale data on soil erodibility, land use, and runoff for the assessment of potential source areas within an intensively agricultural watershed. The agricultural non-point source pollution (AGNPS) model was used in the Muddy Creek, Ontario, watershed to evaluate the effectiveness of management strategies in decreasing sediment and nutrient [phosphorus (P)] pollution. This analysis was accompanied by the measurement of water-quality parameters (dissolved oxygen, pH, hardness, alkalinity, and turbidity) as well as sediment and P loadings to the creek. Practices aimed at increasing year-round soil cover would be most effective in decreasing sediment and P losses in this watershed. In the second part of this article, we describe a method for characterizing land-cover change in a dynamic urban fringe watershed. The GIS method we developed for the Blackberry Creek, Illinois, watershed will allow us to better account for temporal changes in land use, specifically corn and soybean cover, on an annual basis and to improve on the modeling of watershed processes shown for the Muddy Creek watershed. Our model can be used at different levels of planning with minimal data preprocessing, easily accessible data, and adjustable output scales.

  8. An integrated approach to assess heavy metal source apportionment in peri-urban agricultural soils.

    PubMed

    Huang, Ying; Li, Tingqiang; Wu, Chengxian; He, Zhenli; Japenga, Jan; Deng, Meihua; Yang, Xiaoe

    2015-12-15

    Three techniques (Isotope Ratio Analysis, GIS mapping, and Multivariate Statistical Analysis) were integrated to assess heavy metal pollution and source apportionment in peri-urban agricultural soils. The soils in the study area were moderately polluted with cadmium (Cd) and mercury (Hg), lightly polluted with lead (Pb), and chromium (Cr). GIS Mapping suggested Cd pollution originates from point sources, whereas Hg, Pb, Cr could be traced back to both point and non-point sources. Principal component analysis (PCA) indicated aluminum (Al), manganese (Mn), nickel (Ni) were mainly inherited from natural sources, while Hg, Pb, and Cd were associated with two different kinds of anthropogenic sources. Cluster analysis (CA) further identified fertilizers, waste water, industrial solid wastes, road dust, and atmospheric deposition as potential sources. Based on isotope ratio analysis (IRA) organic fertilizers and road dusts accounted for 74-100% and 0-24% of the total Hg input, while road dusts and solid wastes contributed for 0-80% and 19-100% of the Pb input. This study provides a reliable approach for heavy metal source apportionment in this particular peri-urban area, with a clear potential for future application in other regions. PMID:26257294

  9. An integrated approach to assess heavy metal source apportionment in peri-urban agricultural soils.

    PubMed

    Huang, Ying; Li, Tingqiang; Wu, Chengxian; He, Zhenli; Japenga, Jan; Deng, Meihua; Yang, Xiaoe

    2015-12-15

    Three techniques (Isotope Ratio Analysis, GIS mapping, and Multivariate Statistical Analysis) were integrated to assess heavy metal pollution and source apportionment in peri-urban agricultural soils. The soils in the study area were moderately polluted with cadmium (Cd) and mercury (Hg), lightly polluted with lead (Pb), and chromium (Cr). GIS Mapping suggested Cd pollution originates from point sources, whereas Hg, Pb, Cr could be traced back to both point and non-point sources. Principal component analysis (PCA) indicated aluminum (Al), manganese (Mn), nickel (Ni) were mainly inherited from natural sources, while Hg, Pb, and Cd were associated with two different kinds of anthropogenic sources. Cluster analysis (CA) further identified fertilizers, waste water, industrial solid wastes, road dust, and atmospheric deposition as potential sources. Based on isotope ratio analysis (IRA) organic fertilizers and road dusts accounted for 74-100% and 0-24% of the total Hg input, while road dusts and solid wastes contributed for 0-80% and 19-100% of the Pb input. This study provides a reliable approach for heavy metal source apportionment in this particular peri-urban area, with a clear potential for future application in other regions.

  10. COMBUSTION AREA SOURCES: DATA SOURCES

    EPA Science Inventory

    The report identifies, documents, and evaluates data sources for stationary area source emissions, including solid waste and agricultural burning. Area source emissions of particulate matter, sulfur dioxide, oxides of nitrogen, reactive volatile organic compounds, and carbon mon...

  11. Implicit Solution of Non-Equilibrium Radiation Diffusion Including Reactive Heating Source in Material Energy Equation

    SciTech Connect

    Shumaker, D E; Woodward, C S

    2005-05-03

    In this paper, the authors investigate performance of a fully implicit formulation and solution method of a diffusion-reaction system modeling radiation diffusion with material energy transfer and a fusion fuel source. In certain parameter regimes this system can lead to a rapid conversion of potential energy into material energy. Accuracy in time integration is essential for a good solution since a major fraction of the fuel can be depleted in a very short time. Such systems arise in a number of application areas including evolution of a star and inertial confinement fusion. Previous work has addressed implicit solution of radiation diffusion problems. Recently Shadid and coauthors have looked at implicit and semi-implicit solution of reaction-diffusion systems. In general they have found that fully implicit is the most accurate method for difficult coupled nonlinear equations. In previous work, they have demonstrated that a method of lines approach coupled with a BDF time integrator and a Newton-Krylov nonlinear solver could efficiently and accurately solve a large-scale, implicit radiation diffusion problem. In this paper, they extend that work to include an additional heating term in the material energy equation and an equation to model the evolution of the reactive fuel density. This system now consists of three coupled equations for radiation energy, material energy, and fuel density. The radiation energy equation includes diffusion and energy exchange with material energy. The material energy equation includes reaction heating and exchange with radiation energy, and the fuel density equation includes its depletion due to the fuel consumption.

  12. Phenotypic and genotypic characterization of Vagococcus fluvialis, including strains isolated from human sources.

    PubMed Central

    Teixeira, L M; Carvalho, M G; Merquior, V L; Steigerwalt, A G; Brenner, D J; Facklam, R R

    1997-01-01

    This study presents phenotypic and genotypic data for seven isolates of Vagococcus fluvialis, including four strains recovered from human clinical sources, one strain isolated from an environmental source, and two strains isolated from pigs. On the basis of phenotypic characteristics, most isolates were initially classified as "unidentified enterococci," because they resembled atypical arginine-negative enterococcal species. All seven strains as well as the type strain of V. fluvialis reacted with the AccuProbe Enterococcus genetic probe. The seven isolates had virtually indistinguishable whole-cell protein profiles that were similar to that of the V. fluvialis type strain and distinct from those of Enterococcus and Lactococcus species. DNA-DNA reassociation experiments confirmed that the strains were V. fluvialis. They were 71% or more related to the V. fluvialis type strain under optimum and stringent conditions, with 2.5% or less divergence within related sequences. All strains were susceptible to ampicillin, cefotaxime, trimethoprim-sulfamethoxazole, and vancomycin and were resistant to clindamycin, lomefloxacin, and ofloxacin. Strain-to-strain variation was observed in relation to susceptibilities to 18 other antimicrobial agents. Chromosomal DNA was analyzed by pulsed-field gel electrophoresis (PFGE) after digestion with SmaI. Distinctive PFGE patterns were generated, suggesting the nonclonal nature of V. fluvialis strains. Although the number of strains was small, this report provides molecular characterization of V. fluvialis and the first evidence of a possible connection of this species with human infections. PMID:9350732

  13. Plants as sources of airborne bacteria, including ice nucleation-active bacteria.

    PubMed

    Lindemann, J; Constantinidou, H A; Barchet, W R; Upper, C D

    1982-11-01

    Vertical wind shear and concentration gradients of viable, airborne bacteria were used to calculate the upward flux of viable cells above bare soil and canopies of several crops. Concentrations at soil or canopy height varied from 46 colony-forming units per m over young corn and wet soil to 663 colony-forming units per m over dry soil and 6,500 colony-forming units per m over a closed wheat canopy. In simultaneous samples, concentrations of viable bacteria in the air 10 m inside an alfalfa field were fourfold higher than those over a field with dry, bare soil immediately upwind. The upward flux of viable bacteria over alfalfa was three- to fourfold greater than over dry soil. Concentrations of ice nucleation-active bacteria were higher over plants than over soil. Thus, plant canopies may constitute a major source of bacteria, including ice nucleation-active bacteria, in the air.

  14. Stream sediment sources in midwest agricultural basins with land retirement along channel

    USGS Publications Warehouse

    Williamson, Tanja N.; Christensen, Victoria G.; Richardson, William B.; Frey, Jeffrey W.; Gellis, Allen C.; Kieta, K. A.; Fitzpatrick, Faith A.

    2014-01-01

    Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our hypotheses were that sediment from cropland, retired land, stream banks, and roads would be discernible using isotopic and elemental concentrations and that source contributions would vary with land retirement distribution along tributaries of West Fork Beaver Creek in Minnesota. Channel-bed and suspended sediment were sampled at nine locations and compared with local source samples by using linear discriminant analysis and a four-source mixing model that evaluated seven tracers: In, P, total C, Be, Tl, Th, and Ti. The proportion of sediment sources differed significantly between suspended and channel-bed sediment. Retired land contributed to channel-bed sediment but was not discernible as a source of suspended sediment, suggesting that retired-land material was not mobilized during high-flow conditions. Stream banks were a large contributor to suspended sediment; however, the percentage of stream-bank sediment in the channel bed was lower in basins with more continuous retired land along the riparian corridor. Cropland sediments had the highest P concentrations; basins with the highest cropland-sediment contributions also had the highest P concentrations. Along stream reaches with retired land, there was a lower proportion of cropland material in suspended sediment relative to sites that had almost no land retirement, indicating less movement of nutrients and sediment from cropland to the channel as a result of land retirement.

  15. Stream Sediment Sources in Midwest Agricultural Basins with Land Retirement along Channel.

    PubMed

    Williamson, T N; Christensen, V G; Richardson, W B; Frey, J W; Gellis, A C; Kieta, K A; Fitzpatrick, F A

    2014-09-01

    Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our hypotheses were that sediment from cropland, retired land, stream banks, and roads would be discernible using isotopic and elemental concentrations and that source contributions would vary with land retirement distribution along tributaries of West Fork Beaver Creek in Minnesota. Channel-bed and suspended sediment were sampled at nine locations and compared with local source samples by using linear discriminant analysis and a four-source mixing model that evaluated seven tracers: In, P, total C, Be, Tl, Th, and Ti. The proportion of sediment sources differed significantly between suspended and channel-bed sediment. Retired land contributed to channel-bed sediment but was not discernible as a source of suspended sediment, suggesting that retired-land material was not mobilized during high-flow conditions. Stream banks were a large contributor to suspended sediment; however, the percentage of stream-bank sediment in the channel bed was lower in basins with more continuous retired land along the riparian corridor. Cropland sediments had the highest P concentrations; basins with the highest cropland-sediment contributions also had the highest P concentrations. Along stream reaches with retired land, there was a lower proportion of cropland material in suspended sediment relative to sites that had almost no land retirement, indicating less movement of nutrients and sediment from cropland to the channel as a result of land retirement. PMID:25603248

  16. Understanding Multifunctional Agricultural Land by Using Low Cost and Open Source Solutions to Quantify Ecosystem Function and Services

    NASA Astrophysics Data System (ADS)

    Forsmoo, Joel; Anderson, Karen; Brazier, Richard; Macleod, Kit; Wilkinson, Mark

    2016-04-01

    There is a need to advance our understanding of how the spatial structure of farmed landscapes contributes to the provision of functions and services. Agricultural land is of critical importance in NW Europe, covering large parts of NW Europe's temperate land. Moreover, these agricultural areas are primarily intensively managed, with a focus on maximizing food and fibre production. Such landscapes therefore can provide a wealth of ecosystem goods and services (ESs) including regulation of climate, erosion regulation, hydrology, water quality, nutrient cycling and biodiversity conservation. However, it has been shown they are key sources of sediment, phosphorous, nitrogen and storm runoff contributing to flooding, and therefore it is likely that most agricultural landscapes do not maximize the services or benefits that they might provide. The focus of this study is the spatio-temporal assessment of carbon sequestration (particularly through proxies such as above-ground biomass) and hydrological processes on agricultural land. Understanding and quantifying both of these is important to (a) inform payments for ecosystem services frameworks, (b) evaluate and improve carbon sequestration models, (c) manage the flood risk, (d) downstream water security and (e) water quality. Quantifying both of these ESs is dependent on data describing the fine spatial and temporal structure and function of the landscape. Common practice has been to use remote sensing techniques, e.g. satellites, providing coarse spatial resolution (around 30cm at 20° off nadir) and/or temporal resolution (around 5 days revisit time at <20° off nadir). In this paper we will explain how imaging data from lightweight and easily deployed unmanned aerial vehicles (UAVs) can be used to generate structure from motion (SFM) products describing the very fine detailed (<3 cm pixel resolution) structure of the agricultural environment. We will demonstrate how these products can be delivered using advanced free

  17. Estimate of tsunami source using optimized unit sources and including dispersion effects during tsunami propagation: The 2012 Haida Gwaii earthquake

    NASA Astrophysics Data System (ADS)

    Gusman, Aditya Riadi; Mulia, Iyan Eka; Satake, Kenji; Watada, Shingo; Heidarzadeh, Mohammad; Sheehan, Anne F.

    2016-09-01

    We apply a genetic algorithm to find the optimized unit sources using dispersive tsunami synthetics to estimate the tsunami source of the 2012 Haida Gwaii earthquake. The optimal number and distribution of unit sources gives the sea surface elevation similar to that from our previous slip distribution on a fault using tsunami data, but different from that using seismic data. The difference is possibly due to submarine mass failure in the source region. Dispersion effects during tsunami propagation reduce the maximum amplitudes by up to 20% of conventional linear longwave propagation model. Dispersion effects also increase tsunami travel time by approximately 1 min per 1300 km on average. The dispersion effects on amplitudes depend on the azimuth from the tsunami source reflecting the directivity of tsunami source, while the effects on travel times depend only on the distance from the source.

  18. Simulation of stress waves in attenuating drill strings, including piezoelectric sources and sensors

    PubMed

    Carcione; Poletto

    2000-07-01

    A key element in drill steering and prediction of lithology ahead-of-the-bit is the transmission of while-drilling information from the bottom of the well to the rig operator and the geophysicists. Mud-pulse telemetry, based on pressure pulses along the drilling mud and extensional waves through the drill string, is the most used technique. The last method, properly designed, could transmit data rates up to 100 bits per second, against the 1 or 2 bits per second achieved with pressure pulses. In this work, a time-domain algorithm is developed for the propagation of one-dimensional axial, torsional, and flexural stress waves, including transducer sources and sensors. In addition, the equations include relaxation mechanisms simulating the viscoelastic behavior of the steel, dielectric losses, and any other losses, such as those produced by the presence of the drilling mud, the casing, and the formation. Moreover, the algorithm simulates the passbands and stopbands due to the presence of the coupling joints and pulse distortion and delay due to nonuniform cross-section areas. Acoustic and electric pulses, generated at one location in the string, can be propagated and detected at any other location by piezoelectric and acoustic sensors, such as PCB accelerometers, clamp-on ammeters, force, and strain transducers.

  19. COMPARATIVE DIVERSITY OF FECAL BACTERIA IN AGRICULTURALLY SIGNIFICANT ANIMALS TO IDENTIFY ALTERNATIVE TARGETS FOR MICROBIAL SOURCE TRACKING

    EPA Science Inventory

    Animals of agricultural significance contribute a large percentage of fecal pollution to waterways via runoff contamination. The premise of microbial source tracking is to utilize fecal bacteria to identify target populations which are directly correlated to specific animal feces...

  20. Hybrid Design of Electric Power Generation Systems Including Renewable Sources of Energy

    ERIC Educational Resources Information Center

    Wang, Lingfeng; Singh, Chanan

    2008-01-01

    With the stricter environmental regulations and diminishing fossil-fuel reserves, there is now higher emphasis on exploiting various renewable sources of energy. These alternative sources of energy are usually environmentally friendly and emit no pollutants. However, the capital investments for those renewable sources of energy are normally high,…

  1. Energy-Water Nexus Relevant to Baseload Electricity Source Including Mini/Micro Hydropower Generation

    NASA Astrophysics Data System (ADS)

    Fujii, M.; Tanabe, S.; Yamada, M.

    2014-12-01

    Water, food and energy is three sacred treasures that are necessary for human beings. However, recent factors such as population growth and rapid increase in energy consumption have generated conflicting cases between water and energy. For example, there exist conflicts caused by enhanced energy use, such as between hydropower generation and riverine ecosystems and service water, between shale gas and ground water, between geothermal and hot spring water. This study aims to provide quantitative guidelines necessary for capacity building among various stakeholders to minimize water-energy conflicts in enhancing energy use. Among various kinds of renewable energy sources, we target baseload sources, especially focusing on renewable energy of which installation is required socially not only to reduce CO2 and other greenhouse gas emissions but to stimulate local economy. Such renewable energy sources include micro/mini hydropower and geothermal. Three municipalities in Japan, Beppu City, Obama City and Otsuchi Town are selected as primary sites of this study. Based on the calculated potential supply and demand of micro/mini hydropower generation in Beppu City, for example, we estimate the electricity of tens through hundreds of households is covered by installing new micro/mini hydropower generation plants along each river. However, the result is based on the existing infrastructures such as roads and electric lines. This means that more potentials are expected if the local society chooses options that enhance the infrastructures to increase micro/mini hydropower generation plants. In addition, further capacity building in the local society is necessary. In Japan, for example, regulations by the river law and irrigation right restrict new entry by actors to the river. Possible influences to riverine ecosystems in installing new micro/mini hydropower generation plants should also be well taken into account. Deregulation of the existing laws relevant to rivers and

  2. An investigation of element ratios for assessing suspended-sediment sources in small agricultural basins

    USGS Publications Warehouse

    Juracek, K.

    2012-01-01

    Various sediment properties previously have been investigated for the purpose of determining sources of suspended sediment. A remaining research need is an assessment of element ratios for the determination of suspended-sediment sources in different terrestrial environments. In this study, 253 element ratios were assessed to determine which, if any, were potentially useful for sediment-source determinations in six small agricultural basins in northeastern Kansas, USA. Samples of surface soils (cropland and grassland), channel banks, and reservoir bottom sediments were collected, analyzed for 23 elements, and compared. Of the 253 element ratios assessed, only the Co/Pb and Co/Zn ratios were substantially and consistently different between the channel banks and surface soils for all six basins. For three of four reservoirs for which data were available, sediment-source estimates provided by Co/Pb ratios were in agreement with estimates previously provided using 137Cs. For two of the four reservoirs, sediment-source estimates provided by Co/Zn ratios were consistent with the 137Cs estimates. Thus, the Co/Pb ratio potentially may be more useful. Additional research is needed to ascertain whether or not the use of Co/Pb and Co/Zn ratios as tracers is widely applicable or restricted to specific terrestrial environments.

  3. Chloride Sources and Losses in Two Tile-Drained Agricultural Watersheds.

    PubMed

    David, Mark B; Mitchell, Corey A; Gentry, Lowell E; Salemme, Ronald K

    2016-01-01

    Chloride is a relatively unreactive plant nutrient that has long been used as a biogeochemical tracer but also can be a pollutant causing aquatic biology impacts when concentrations are high, typically from rock salt applications used for deicing roads. Chloride inputs to watersheds are most often from atmospheric deposition, road salt, or agricultural fertilizer, although studies on agricultural watersheds with large fertilizer inputs are few. We used long-term (21 and 17 yr) chloride water quality data in two rivers of east-central Illinois to better understand chloride biogeochemistry in two agricultural watersheds (Embarras and Kaskaskia), the former with a larger urban land use and both with extensive tile drainage. During our sampling period, the average chloride concentration was 23.7 and 20.9 mg L in the Embarras and Kaskaskia Rivers, respectively. Annual fluxes of chloride were 72.5 and 61.2 kg ha yr in the Embarras and Kaskaskia watersheds, respectively. In both watersheds, fertilizer chloride was the dominant input (∼49 kg ha yr), with road salt likely the other major source (23.2 and 7.2 kg ha yr for the Embarras and Kaskaskia watersheds, respectively). Combining our monitoring data with earlier published data on the Embarras River showed an increase in chloride concentrations as potash use increased in Illinois during the 1960s and 1970s with a lag of about 2 to 6 yr to changes in potash inputs based on a multiple-regression model. In these agricultural watersheds, riverine chloride responds relatively quickly to potash fertilization as a result of tile-drainage.

  4. Chloride Sources and Losses in Two Tile-Drained Agricultural Watersheds.

    PubMed

    David, Mark B; Mitchell, Corey A; Gentry, Lowell E; Salemme, Ronald K

    2016-01-01

    Chloride is a relatively unreactive plant nutrient that has long been used as a biogeochemical tracer but also can be a pollutant causing aquatic biology impacts when concentrations are high, typically from rock salt applications used for deicing roads. Chloride inputs to watersheds are most often from atmospheric deposition, road salt, or agricultural fertilizer, although studies on agricultural watersheds with large fertilizer inputs are few. We used long-term (21 and 17 yr) chloride water quality data in two rivers of east-central Illinois to better understand chloride biogeochemistry in two agricultural watersheds (Embarras and Kaskaskia), the former with a larger urban land use and both with extensive tile drainage. During our sampling period, the average chloride concentration was 23.7 and 20.9 mg L in the Embarras and Kaskaskia Rivers, respectively. Annual fluxes of chloride were 72.5 and 61.2 kg ha yr in the Embarras and Kaskaskia watersheds, respectively. In both watersheds, fertilizer chloride was the dominant input (∼49 kg ha yr), with road salt likely the other major source (23.2 and 7.2 kg ha yr for the Embarras and Kaskaskia watersheds, respectively). Combining our monitoring data with earlier published data on the Embarras River showed an increase in chloride concentrations as potash use increased in Illinois during the 1960s and 1970s with a lag of about 2 to 6 yr to changes in potash inputs based on a multiple-regression model. In these agricultural watersheds, riverine chloride responds relatively quickly to potash fertilization as a result of tile-drainage. PMID:26828190

  5. Sugarcane Aphid (Hemiptera: Aphididae): Host Range and Sorghum Resistance Including Cross-Resistance From Greenbug Sources.

    PubMed

    Armstrong, J Scott; Rooney, William L; Peterson, Gary C; Villenueva, Raul T; Brewer, Michael J; Sekula-Ortiz, Danielle

    2015-04-01

    The graminous host range and sources of sorghum [Sorghum bicolor (L.) Moench.] plant resistance, including cross-resistance from greenbug, Schizaphis graminum (Rondani), were studied for the newly emerging sugarcane aphid, Melanaphis sacchari (Zehntner), in greenhouse no-choice experiments and field evaluations. The sugarcane aphid could not survive on field corn, Zea mays (L.), Teff grass, Eragrostis tef (Zucc.), proso millet, Panicum miliaceum L., barley, Hordeum vulgare L., and rye, Secale cereale L. Only sorghum genotypes served as hosts including Johnsongrass, Sorghum halepense (L.), a highly suitable noncrop host that generates high numbers of sugarcane aphid and maintains moderate phenotypic injury. The greenbug-resistant parental line RTx2783 that is resistant to greenbug biotypes C and E was resistant to sugarcane aphid in both greenhouse and field tests, while PI 55607 greenbug resistant to biotypes B, C, and E was highly susceptible. PI 55610 that is greenbug resistant to biotypes B, C, and E maintained moderate resistance to the sugarcane aphid, while greenbug-resistant PI 264453 was highly susceptible to sugarcane aphid. Two lines and two hybrids from the Texas A&M breeding program B11070, B11070, AB11055-WF1-CS1/RTx436, and AB11055-WF1-CS1/RTx437 were highly resistant to sugarcane aphid, as were parental types SC110, SC170, and South African lines Ent62/SADC, (Macia/TAM428)-LL9, (SV1*Sima/IS23250)-LG15. Tam428, a parental line that previously showed moderate resistance in South Africa and India, also showed moderate resistance in these evaluations. Overall, 9 of 20 parental sorghum entries tested for phenotypic damage in the field resulted in good resistance to the sugarcane aphid and should be utilized in breeding programs that develop agronomically acceptable sorghums for the southern regions of the United States.

  6. Sugarcane Aphid (Hemiptera: Aphididae): Host Range and Sorghum Resistance Including Cross-Resistance From Greenbug Sources.

    PubMed

    Armstrong, J Scott; Rooney, William L; Peterson, Gary C; Villenueva, Raul T; Brewer, Michael J; Sekula-Ortiz, Danielle

    2015-04-01

    The graminous host range and sources of sorghum [Sorghum bicolor (L.) Moench.] plant resistance, including cross-resistance from greenbug, Schizaphis graminum (Rondani), were studied for the newly emerging sugarcane aphid, Melanaphis sacchari (Zehntner), in greenhouse no-choice experiments and field evaluations. The sugarcane aphid could not survive on field corn, Zea mays (L.), Teff grass, Eragrostis tef (Zucc.), proso millet, Panicum miliaceum L., barley, Hordeum vulgare L., and rye, Secale cereale L. Only sorghum genotypes served as hosts including Johnsongrass, Sorghum halepense (L.), a highly suitable noncrop host that generates high numbers of sugarcane aphid and maintains moderate phenotypic injury. The greenbug-resistant parental line RTx2783 that is resistant to greenbug biotypes C and E was resistant to sugarcane aphid in both greenhouse and field tests, while PI 55607 greenbug resistant to biotypes B, C, and E was highly susceptible. PI 55610 that is greenbug resistant to biotypes B, C, and E maintained moderate resistance to the sugarcane aphid, while greenbug-resistant PI 264453 was highly susceptible to sugarcane aphid. Two lines and two hybrids from the Texas A&M breeding program B11070, B11070, AB11055-WF1-CS1/RTx436, and AB11055-WF1-CS1/RTx437 were highly resistant to sugarcane aphid, as were parental types SC110, SC170, and South African lines Ent62/SADC, (Macia/TAM428)-LL9, (SV1*Sima/IS23250)-LG15. Tam428, a parental line that previously showed moderate resistance in South Africa and India, also showed moderate resistance in these evaluations. Overall, 9 of 20 parental sorghum entries tested for phenotypic damage in the field resulted in good resistance to the sugarcane aphid and should be utilized in breeding programs that develop agronomically acceptable sorghums for the southern regions of the United States. PMID:26470168

  7. User's Guide for the Agricultural Non-Point Source (AGNPS) Pollution Model Data Generator

    USGS Publications Warehouse

    Finn, Michael P.; Scheidt, Douglas J.; Jaromack, Gregory M.

    2003-01-01

    BACKGROUND Throughout this user guide, we refer to datasets that we used in conjunction with developing of this software for supporting cartographic research and producing the datasets to conduct research. However, this software can be used with these datasets or with more 'generic' versions of data of the appropriate type. For example, throughout the guide, we refer to national land cover data (NLCD) and digital elevation model (DEM) data from the U.S. Geological Survey (USGS) at a 30-m resolution, but any digital terrain model or land cover data at any appropriate resolution will produce results. Another key point to keep in mind is to use a consistent data resolution for all the datasets per model run. The U.S. Department of Agriculture (USDA) developed the Agricultural Nonpoint Source (AGNPS) pollution model of watershed hydrology in response to the complex problem of managing nonpoint sources of pollution. AGNPS simulates the behavior of runoff, sediment, and nutrient transport from watersheds that have agriculture as their prime use. The model operates on a cell basis and is a distributed parameter, event-based model. The model requires 22 input parameters. Output parameters are grouped primarily by hydrology, sediment, and chemical output (Young and others, 1995.) Elevation, land cover, and soil are the base data from which to extract the 22 input parameters required by the AGNPS. For automatic parameter extraction, follow the general process described in this guide of extraction from the geospatial data through the AGNPS Data Generator to generate input parameters required by the pollution model (Finn and others, 2002.)

  8. Source identification of nitrate in groundwater using stable isotopes and Cl/Br ratios in an agricultural area

    NASA Astrophysics Data System (ADS)

    Koh, D.; Mayer, B.

    2009-12-01

    Sources of nitrate in groundwater were investigated in an agricultural area with natural area at higher altitude, upland at hilly terrains and residential areas at low-lying lands using δ15N and δ18O of nitrate and Cl/Br ratios. The NO3- concentration in groundwater was as high as 49 mg/L, with an average of 6.0 mg/L and a median value of 4.4 mg/L as NO3-N, and, 22% of the groundwater samples exceeded the DWS of South Korea, which is 10 mg/L for NO3-N. Nitrate sources were consistently identified in residential and upland areas using stable isotopes of nitrate and Cl/Br ratios which showed that the higher δ15N-NO3- and Cl/Br ratios in residential area and lower δ15N-NO3- and Cl/Br ratios in upland Meanwhile, contribution of atmospheric nitrate in natural area was not readily observable due to resetting of δ18O-NO3- in the soil zone. The higher δ15N-NO3- values in residential area was consistent with higher Cl/Br ratios indicating the effect of domestic wastewater including sewage and septic effluents. Upland area had δ15N-NO3- corresponding to soil organic nitrogen which seems resulted from mixed sources of mineralized fertilizer and manure with higher contribution of the latter. The lower Cl/Br ratios of upland area compared to residential area indicates higher contribution of agrochemicals including fertilizers and pesticides. Statistical comparison of chemical and isotopic parameters according to land-use groups revealed that nitrate concentrations and Cl/Br ratios were distinctive between four land uses considered whereas stable isotopes of nitrate were not significantly different between anthropogenic land uses indicating Cl/Br ratio is a more efficient tracer for impact of land-uses on groundwater quality in agricultural areas.

  9. Comparing bottom-up and top-down approaches at the landscape scale, including agricultural activities and water systems, at the Roskilde Fjord, Denmark

    NASA Astrophysics Data System (ADS)

    Lequy, Emeline; Ibrom, Andreas; Ambus, Per; Massad, Raia-Silvia; Markager, Stiig; Asmala, Eero; Garnier, Josette; Gabrielle, Benoit; Loubet, Benjamin

    2015-04-01

    The greenhouse gas nitrous oxide (N2O) mainly originates in direct emissions from agricultural soils due to microbial reactions stimulated by the use of nitrogen fertilisers. Indirect N2O emissions from water systems due to nitrogen leaching and deposition from crop fields range between 26 and 37% of direct agricultural emissions, indicating their potential importance and uncertainty (Reay et al. 2012). The study presented here couples a top-down approach with eddy covariance (EC) and a bottom-up approach using different models and measurements. A QCL sensor at 96-m height on a tall tower measures the emissions of N2O from 1100 ha of crop fields and from the south part of the Roskilde fjord, in a 5-km radius area around the tall tower at Roskilde, Denmark. The bottom-up approach includes ecosystem modelling with CERES-EGC for the crops and PaSIM for the grasslands, and the N2O fluxes from the Roskilde fjord are derived from N2O sea water concentration measurements. EC measurements are now available from July to December 2014, and indicate a magnitude of the emissions from the crop fields around 0.2 mg N2O-N m-2 day-1 (range -9 to 5) which is consistent with the CERES-EGC simulations and calculations using IPCC emission factors. N2O fluxes from the Roskilde fjord in May and July indicated quite constant N2O concentrations around 0.1 µg N L-1 despite variations of nitrate and ammonium in the fjord. The calculated fluxes from these concentrations and the tall tower measurements consistently ranged between -7 and 6 mg N2O-N m-2 day-1. The study site also contains a waste water treatment plant, whose direct emissions will be measured in early 2015 using a dynamic plume tracer dispersion method (Mønster et al. 2014). A refined source attribution methodology together with more measurements and simulations of the N2O fluxes from the different land uses in this study site will provide a clearer view of the dynamics and budgets of N2O at the regional scale. The

  10. Basic biogenic aerosol precursors: Agricultural source attribution of volatile amines revised

    NASA Astrophysics Data System (ADS)

    Kuhn, U.; Sintermann, J.; Spirig, C.; Jocher, M.; Ammann, C.; Neftel, A.

    2011-08-01

    Despite recent evidence on an important role of volatile amines in the nucleation of particulate matter, very scarce information is available on their atmospheric abundance and source distribution. Previous measurements in animal housings had identified livestock husbandry as the main amine source, with trimethylamine (TMA) being the key component. This has led to the assumption that the agricultural sources for amines are similar as for ammonia, emitted throughout the cascade of animal excretion, storage and application in the field. In this study, we present the first micrometeorological flux measurements as well as dynamic enclosure experiments showing that the amine source strength from stored slurry is negligible, implying significant consequences for the global amine emission inventory. In the case of cattle, amine production is attributed to the animal's rumination activity and exhalation is suggested to be an important emission pathway, similar to the greenhouse gas methane. Fodder like hay and silage also emits volatile amines, potentially assigning these alkaloid compounds a key function in enhancing particle formation in remote areas.

  11. Radio Properties of Low Redshift Broad Line Active Galactic Nuclei Including Multiple Component Radio Sources

    NASA Astrophysics Data System (ADS)

    Rafter, Stephen E.

    2010-01-01

    We present results on the radio properties of a low redshift (z < 0.35) sample of 8434 broad line active galactic nuclei (AGNs) from the Sloan Digital Sky Survey after correlating the optical sources with radio sources in the Faint Images of the Radio Sky at Twenty-Centimeters survey. We find that 10% of our sample has radio emission < 4" away from the optical counterpart (core-only sources), and 1% has significant extended emission that must be taken into account when calculating the total radio luminosity (multi-component sources). Association of the extended radio emission is established by the proximity to the optical source, physical connection of jets and lobes, or large scale symmetry like in classic FRIIs. From these data we find an FRI/FRII luminosity dividing line like that found by Fanaroff & Riley (1974), where we use our core-only sources as proxies for FRIs, and our multi-component sources for the FRIIs. We find a bimodal distribution for the radio loudness (R = L(radio)/L(opt)) where the lower radio luminosity core-only sources appear as a population separate from the multi-component extended sources, compared with no evidence for bimodality when just the core-only sources are used. We also find that a log(R) value of 1.75 is well suited to separate the FRIs from the FRIIs, and that the R bimodality seen here is really a manifestation of the FRI/FRII break originally found by Fanaroff & Riley (1974). We find modest trends in the radio loud fraction as a function of Eddington ratio and black hole mass, where the fraction of RL AGNs decreases with increasing Eddington ratio, and increases when the black hole mass is above 2 x 108 solar masses.

  12. Surface Time-Variable Gravity Signals and Possible Sources Including Core Mass Flow

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.; Kuang, Weijia

    2003-01-01

    Over two decades of geodetic satellite-laser-ranging (SLR) data show that the variation of the Earth's oblateness parameter J2 has a clear seasonal signal of amplitude of about 3e-10 and a secular decrease of about -2.8e-11/year, superimposed on some interesting interannual fluctuations. Physically, any change in mass distribution or/inside the Earth will be reflected in the time-variable gravity signal obtained outside the Earth, according to Newton s gravitational law. Therefore, such signal contains contributions from all geophysical sources that redistribute mass, on all temporal and spatial scales, including those from the core. Besides Earth rotation and geomagnetic field variations, the time-variable gravity also contains information linking Earth surface observations with internal core dynamical processes. The time scales of the gravity signal are critical in helping differentiate different contributions. The atmosphere and hydrosphere are responsible for the seasonal and much of the interannual and intraseasoanl fluctuations, while the secular trend is due mainly to the post-glacial rebound but possibly core mass flow. To estimate the latter effect, we use our MoSST (Modular, Scalable, Self-consistent, Three-dimensional) core dynamics model to forward simulate the core flow, and density variation due to the core convection. Our results suggest that, when upward continued to the surface, the J2 component of the core mass redistribution can reach an overall amplitude of e-11/year, approaching the SLR detectability and significant in geophysical terms. We also find a general westward drift of the mass flow, with a speed comparable to that of the geomagnetic westward drift.

  13. Potential sources of and ecological risks from heavy metals in agricultural soils, Daye City, China.

    PubMed

    Du, Ping; Xie, Yunfeng; Wang, Shijie; Zhao, Huanhuan; Zhang, Zhuo; Wu, Bin; Li, Fasheng

    2015-03-01

    Concentrations of eight heavy metals (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn)) were measured in 92 topsoil samples collected from agricultural areas in Daye City to (1) assess the distribution of these heavy metals, (2) discriminate natural and anthropic contributions, and (3) identify possible sources of pollution. Mean concentrations of As, Cd, Cu, and Zn in the investigated soils were 23.8, 1.41, 105, and 159 mg kg(-1), respectively. These values were higher, in some cases by several orders of magnitude, than their corresponding background values. Estimated ecological risks, based on contamination factors and potential ecological risk indexes, were mostly low, but were considerable for As and Cd. A range of basic and multivariate statistical analyses (Pearson's correlation analysis, hierarchical cluster analysis, and principal component analysis) clearly revealed two distinct metal groups, comprising As/Cd/Cu/Zn and Cr/Ni/Hg/Pb, whose concentrations were closely associated with the distribution and pollution characteristics of industries in and around the city. Results demonstrated that As/Cd/Cu/Zn were indicators of anthropic pollution, while Cr/Hg/Ni/Pb were from parent materials. Maps of pollutant distribution compiled for the entire arable area further indicated that non-ferrous metal smelting and mining is the main source of diffuse pollution, and also showed the contribution of point source pollution to metal concentrations in agricultural topsoil. Results of this study will be useful for planning, risk assessment, and decision making by environmental managers in this region. PMID:25242589

  14. Potential sources of and ecological risks from heavy metals in agricultural soils, Daye City, China.

    PubMed

    Du, Ping; Xie, Yunfeng; Wang, Shijie; Zhao, Huanhuan; Zhang, Zhuo; Wu, Bin; Li, Fasheng

    2015-03-01

    Concentrations of eight heavy metals (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn)) were measured in 92 topsoil samples collected from agricultural areas in Daye City to (1) assess the distribution of these heavy metals, (2) discriminate natural and anthropic contributions, and (3) identify possible sources of pollution. Mean concentrations of As, Cd, Cu, and Zn in the investigated soils were 23.8, 1.41, 105, and 159 mg kg(-1), respectively. These values were higher, in some cases by several orders of magnitude, than their corresponding background values. Estimated ecological risks, based on contamination factors and potential ecological risk indexes, were mostly low, but were considerable for As and Cd. A range of basic and multivariate statistical analyses (Pearson's correlation analysis, hierarchical cluster analysis, and principal component analysis) clearly revealed two distinct metal groups, comprising As/Cd/Cu/Zn and Cr/Ni/Hg/Pb, whose concentrations were closely associated with the distribution and pollution characteristics of industries in and around the city. Results demonstrated that As/Cd/Cu/Zn were indicators of anthropic pollution, while Cr/Hg/Ni/Pb were from parent materials. Maps of pollutant distribution compiled for the entire arable area further indicated that non-ferrous metal smelting and mining is the main source of diffuse pollution, and also showed the contribution of point source pollution to metal concentrations in agricultural topsoil. Results of this study will be useful for planning, risk assessment, and decision making by environmental managers in this region.

  15. Evaluating nitrate sources in nested agricultural sub-basins using nitrate stable isotopes

    NASA Astrophysics Data System (ADS)

    Chang, C. C.; Frey, J. W.; Kim, M.; Kendall, C.

    2005-05-01

    Nutrient enrichment is the second leading cause of drinking water contamination in the United States. To provide environmental managers with nutrient source and transport information, the U.S. Geological Survey' s National Water-Quality Assessment (NAWQA) Program conducted a multi-component study in Sugar Creek Basin, Indiana, in which major nutrients, cations, anions, and pesticides were analyzed. Land use at Sugar Creek (246 square km basin) is dominated by row crop agriculture, primarily corn and soybeans. The soils are largely heavy clay, glacial till in origin, and require tile drains to move excess water and make the land farmable. As one component of the study, stable isotopes of nitrate (N-15 and O-18) were used to examine nitrate sources and transport, and possible transformations of nitrate. Water samples were collected in 2003 and 2004 from major environmental compartments involved with the movement of nutrients into the creek, (precipitation, tile drain, and overland flow). Samples were also collected from Leary-Weber Ditch, a 6.2 square km basin is nested within Sugar Creek. Collection times bracketing four distinct periods of the agricultural cycle: pre-application of fertilizer, post-application of fertilizer, growing season, and post-harvest periods. Nutrient samples (nitrate, phosphate, ammonia) were also collected several times between storm events during baseflow conditions. Preliminary nutrient and pesticide data indicate that tile drains are the primary pathway into streams. Little interaction occurs between the ground water and surface water interface. Nitrate stable isotopes will enable us to determine the relative contribution of nitrate sources feeding in from the tile drains, into Leary-Weber Ditch and Sugar Creek.

  16. Downstream mixing of sediment and tracers in agricultural catchments: Evidence of changing sediment sources and fluvial processes?

    NASA Astrophysics Data System (ADS)

    Ralph, Timothy; Wethered, Adam; Smith, Hugh; Heijnis, Henk

    2014-05-01

    Land clearance, soil tillage and grazing in agricultural catchments have liberated sediment and altered hydrological connectivity between hillslopes and channels, leading to increased sediment availability, mobilisation and delivery to rivers. The type and amount of sediment supplied to rivers is critical for fluvial geomorphology and aquatic ecosystem health. Contemporary sediment dynamics are routinely investigated using environmental radionuclides such as caesium-137 (Cs-137) and excess lead-210 (Pb-210ex), which can provide information regarding sediment source types and fluvial processes if sediment sources can be distinguished from one another and mixing models applied to representative samples. However, downstream transport, mixing and dilution of radionuclide-labelled sediment (especially from sources with low initial concentrations) can obliterate the tracer signal; sometimes before anything of geomorphological importance happens in the catchment. Can these findings be used as evidence of sediment source variations and fluvial processes when the limits of detection (of Cs-137 in particular) are being exceeded so rapidly downstream? Sediment sources and downstream sediment dynamics were investigated in Coolbaggie Creek, a major supplier of sediment to the Macquarie River in an agricultural catchment with temperate to semi-arid climate in Australia. Radionuclides were used to discriminate between the <63 micron fraction of sediment sources including forested topsoils (Cs-137 11.28 +/- 0.75 Bq/kg; Pb-210ex 181.87 +/- 20.00 Bq/kg), agricultural topsoils (Cs-137 3.21 +/- 0.26 Bq/kg; Pb-210ex 29.59 +/- 10.94 Bq/kg) and sub-soils from channel banks and gullies (Cs-137 1.45 +/- 0.47 Bq/kg; Pb-210ex 4.67 +/- 1.93 Bq/kg). Within the trunk stream, suspended sediment, organic matter and Cs-137 and Pb-210ex concentrations declined downstream. Results from a mixing model suggest that agricultural topsoils account for 95% of fine sediment entering the channel in the

  17. Extraction of whole versus ground source rocks: Fundamental petroleum geochemical implications including oil-source rock correlation

    USGS Publications Warehouse

    Price, L.C.; Clayton, J.L.

    1992-01-01

    In petroleum geochemistry, extractable hydrocarbons (HCs) in source rocks have typically been studied by grinding the rock to a fine powder (???100 mesh) and then extracting the HCs from the rock with a solvent. This procedure carries the implicit assumption that the HCs are homogeneously distributed throughout the rock. However, sequential Soxhlet extractions of whole (unpowdered) source rocks have shown that progressive extracts from the same rock can be quite different and may not even correlate with each other. A crude oil-like material clearly has been fractionated from indigenous bitumen in these rocks, has moved to cracks and parting laminae in the rocks, is ready for expulsion from the rocks, and is thus most accessible to the first extracting solvents. This process, which we believe is largely due to HC gases and carbon dioxide generated over all maturation ranks in source rocks, carries petroleum geochemical implications of a fundamental nature for oil-source rock correlations and gives insight into primary migration mechanisms, origin of oil deposits, and use of maturity and organic-facies indices. ?? 1992.

  18. Nonpoint Source Pollution: Agriculture, Forestry, and Mining. Instructor Guide. Working for Clean Water: An Information Program for Advisory Groups.

    ERIC Educational Resources Information Center

    Buskirk, E. Drannon, Jr.

    Nonpoint sources of pollution have diffuse origins and are major contributors to water quality problems in both urban and rural areas. Addressed in this instructor's manual are the identification, assessment, and management of nonpoint source pollutants resulting from mining, agriculture, and forestry. The unit, part of the Working for Clean Water…

  19. Semi-Empirical Characterization of Ground Motions Including Source, Path and Nonlinear Site Effects

    NASA Astrophysics Data System (ADS)

    Seyhan, Emel

    The objective of this thesis is to improve the physical understanding of earthquake ground motion characteristics related to source, path and nonlinear site effects and our ability to model those effects with engineering models. Site database work was performed within the context of the NGA-West 2 project. Starting with the site database from original (2008) NGA project (last edited in 2006), we provided site classifications for 2538 new sites and re-classifications of previous sites. The principal site parameter is the time-averaged shear wave velocity in the upper 30 m (Vs30 ), which is characterized using measurements where available, and proxy-based relationships otherwise. We improved the documentation and consistency of site descriptors used as proxies for the estimation of Vs30, developed evidence-based protocols for Vs30 estimation from available proxies, and augmented estimates of various basin depth parameters. Site factors typically have a small-strain site amplification that captures impedance and resonance effects coupled with nonlinear components. Site factors in current NEHRP Provisions are empirically-derived at relatively small ground motion levels and feature simulation-based nonlinearity. We show that current NEHRP site factors have discrepancies with respect to the site terms in the original NGA GMPEs both in the linear site amplification (especially for Classes B, C, D, and E) and the degree of nonlinearity (Classes C and D). We analyzed the NGA-West 2 dataset and simulation-based models for site amplification to develop a new model. The model has linear and nonlinear additive components. The linear component is fully empirical, being derived from worldwide ground motion data (regional effects were examined but found to not be sufficiently important to be included in the model). The model features linear Vs30-scaling in a log-log sense below a corner velocity (Vc), and no Vs30-scaling for velocities faster than Vc. The nonlinear component is

  20. Evaluating agricultural nonpoint-source pollution using integrated geographic information systems and hydrologic/water quality model

    SciTech Connect

    Tim, U.S.; Jolly, R.

    1994-01-01

    Considerable progress has been made in developing physically based, distributed parameter, hydrologic/water quality (HIWQ) models for planning and control of nonpoint-source pollution. The widespread use of these models is often constrained by the excessive and time-consuming input data demands and the lack of computing efficiencies necessary for iterative simulation of alternative management strategies. Recent developments in geographic information systems (GIS) provide techniques for handling large amounts of spatial data for modeling nonpoint-source pollution problems. Because a GIS can be used to combine information from several sources to form an array of model input data and to examine any combinations of spatial input/output data, it represents a highly effective tool for HiWQ modeling. This paper describes the integration of a distributed-parameter model (AGNPS) with a GIS (ARC/INFO) to examine nonpoint sources of pollution in an agricultural watershed. The ARC/INFO GIS provided the tools to generate and spatially organize the disparate data to support modeling, while the AGNPS model was used to predict several water quality variables including soil erosion and sedimentation within a watershed. The integrated system was used to evaluate the effectiveness of several alternative management strategies in reducing sediment pollution in a 417-ha watershed located in southern Iowa. The implementation of vegetative filter strips and contour buffer (grass) strips resulted in a 41 and 47% reduction in sediment yield at the watershed outlet, respectively. In addition, when the integrated system was used, the combination of the above management strategies resulted in a 71% reduction in sediment yield. In general, the study demonstrated the utility of integrating a simulation model with GIS for nonpoini-source pollution control and planning. Such techniques can help characterize the diffuse sources of pollution at the landscape level. 52 refs., 6 figs., 1 tab.

  1. Including signal intensity increases the performance of blind source separation on brain imaging data.

    PubMed

    Li, Ming; Liu, Yadong; Chen, Fanglin; Hu, Dewen

    2015-02-01

    When analyzing brain imaging data, blind source separation (BSS) techniques critically depend on the level of dimensional reduction. If the reduction level is too slight, the BSS model would be overfitted and become unavailable. Thus, the reduction level must be set relatively heavy. This approach risks discarding useful information and crucially limits the performance of BSS techniques. In this study, a new BSS method that can work well even at a slight reduction level is presented. We proposed the concept of "signal intensity" which measures the significance of the source. Only picking the sources with significant intensity, the new method can avoid the overfitted solutions which are nonexistent artifacts. This approach enables the reduction level to be set slight and retains more useful dimensions in the preliminary reduction. Comparisons between the new and conventional algorithms were performed on both simulated and real data. PMID:25314698

  2. Comparison of lead isotopes with source apportionment models, including SOM, for air particulates.

    PubMed

    Gulson, Brian; Korsch, Michael; Dickson, Bruce; Cohen, David; Mizon, Karen; Davis, J Michael

    2007-08-01

    We have measured high precision lead isotopes in PM(2.5) particulates from a highly-trafficked site (Mascot) and rural site (Richmond) in the Sydney Basin, New South Wales, Australia to compare with isotopic data from total suspended particulates (TSP) from other sites in the Sydney Basin and evaluate relationships with source fingerprints obtained from multi-element PM(2.5) data. The isotopic data for the period 1998 to 2004 show seasonal peaks and troughs that are more pronounced in the rural site for the PM(2.5).samples but are consistent with the TSP. The Self Organising Map (SOM) method has been applied to the multi-element PM(2.5) data to evaluate its use in obtaining fingerprints for comparison with standard statistical procedures (ANSTO model). As seasonal effects are also significant for the multi-element data, the SOM modelling is reported as site and season dependent. At the Mascot site, the ANSTO model exhibits decreasing (206)Pb/(204)Pb ratios with increasing contributions of fingerprints for "secondary smoke" (industry), "soil", "smoke" and "seaspray". Similar patterns were shown by SOM winter fingerprints for both sites. At the rural site, there are large isotopic variations but for the majority of samples these are not associated with increased contributions from the main sources with the ANSTO model. For two winter sampling times, there are increased contributions from "secondary industry", "smoke", "soil" and seaspray with one time having a source or sources of Pb similar to that of Mascot. The only positive relationship between increasing (206)Pb/(204)Pb ratio and source contributions is found at the rural site using the SOM summer fingerprints, both of which show a significant contribution from sulphur. Several of the fingerprints using either model have significant contributions from black carbon (BC) and/or sulphur (S) that probably derive from diesel fuels and industrial sources. Increased contributions from sources with the SOM summer

  3. Impacts of input parameter spatial aggregation on an agricultural nonpoint source pollution model

    NASA Astrophysics Data System (ADS)

    FitzHugh, T. W.; Mackay, D. S.

    2000-09-01

    The accuracy of agricultural nonpoint source pollution models depends in part on how well model input parameters describe the relevant characteristics of the watershed. The spatial extent of input parameter aggregation has previously been shown to have a substantial impact on model output. This study investigates this problem using the Soil and Water Assessment Tool (SWAT), a distributed-parameter agricultural nonpoint source pollution model. The primary question addressed here is: how does the size or number of subwatersheds used to partition the watershed affect model output, and what are the processes responsible for model behavior? SWAT was run on the Pheasant Branch watershed in Dane County, WI, using eight watershed delineations, each with a different number of subwatersheds. Model runs were conducted for the period 1990-1996. Streamflow and outlet sediment predictions were not seriously affected by changes in subwatershed size. The lack of change in outlet sediment is due to the transport-limited nature of the Pheasant Branch watershed and the stable transport capacity of the lower part of the channel network. This research identifies the importance of channel parameters in determining the behavior of SWAT's outlet sediment predictions. Sediment generation estimates do change substantially, dropping by 44% between the coarsest and the finest watershed delineations. This change is primarily due to the sensitivity of the runoff term in the Modified Universal Soil Loss Equation to the area of hydrologic response units (HRUs). This sensitivity likely occurs because SWAT was implemented in this study with a very detailed set of HRUs. In order to provide some insight on the scaling behavior of the model two indexes were derived using the mathematics of the model. The indexes predicted SWAT scaling behavior from the data inputs without a need for running the model. Such indexes could be useful for model users by providing a direct way to evaluate alternative models

  4. From deposition to erosion: Spatial and temporal variability of sediment sources, storage, and transport in a small agricultural watershed

    NASA Astrophysics Data System (ADS)

    Florsheim, J. L.; Pellerin, B. A.; Oh, N. H.; Ohara, N.; Bachand, P. A. M.; Bachand, S. M.; Bergamaschi, B. A.; Hernes, P. J.; Kavvas, M. L.

    2011-09-01

    The spatial and temporal variability of sediment sources, storage, and transport were investigated in a small agricultural watershed draining the Coast Ranges and Sacramento Valley in central California. Results of field, laboratory, and historical data analysis in the Willow Slough fluvial system document changes that transformed a transport-limited depositional system to an effective erosion and transport system, despite a large sediment supply. These changes were caused by a combination of factors: (i) an increase in transport capacity, and (ii) hydrologic alteration. Alteration of the riparian zone and drainage network pattern during the past ~ 150 years included a twofold increase in straightened channel segments along with a baselevel change from excavation that increased slope, and increased sediment transport capacity by ~ 7%. Hydrologic alteration from irrigation water contributions also increased transport capacity, by extending the period with potential for sediment transport and erosion by ~ 6 months/year. Field measurements document Quaternary Alluvium as a modern source of fine sediment with grain size distributions characterized by 5 to 40% fine material. About 60% of an upland and 30% of a lowland study reach incised into this deposit exhibit bank erosion. During this study, the wet 2006 and relatively dry 2007 water years exhibited a range of total annual suspended sediment load spanning two orders of magnitude: ~ 108,500 kg/km 2/year during 2006 and 5,950 kg/km 2/year during 2007, only 5% of that during the previous year. Regional implications of this work are illustrated by the potential for a small tributary such as Willow Slough to contribute sediment - whereas large dams limit sediment supply from larger tributaries - to the Sacramento River and San Francisco Bay Delta and Estuary. This work is relevant to lowland agricultural river-floodplain systems globally in efforts to restore aquatic and riparian functions and where water quality

  5. From deposition to erosion: spatial and temporal variability of sediment sources, storage, and transport in a small agricultural watershed

    USGS Publications Warehouse

    Florsheim, J.L.; Pellerin, B.A.; Oh, N.H.; Ohara, N.; Bachand, P.A.M.; Bachand, Sandra M.; Bergamaschi, B.A.; Hernes, P.J.; Kavvas, M.L.

    2011-01-01

    The spatial and temporal variability of sediment sources, storage, and transport were investigated in a small agricultural watershed draining the Coast Ranges and Sacramento Valley in central California. Results of field, laboratory, and historical data analysis in the Willow Slough fluvial system document changes that transformed a transport-limited depositional system to an effective erosion and transport system, despite a large sediment supply. These changes were caused by a combination of factors: (i) an increase in transport capacity, and (ii) hydrologic alteration. Alteration of the riparian zone and drainage network pattern during the past ~ 150 years included a twofold increase in straightened channel segments along with a baselevel change from excavation that increased slope, and increased sediment transport capacity by ~ 7%. Hydrologic alteration from irrigation water contributions also increased transport capacity, by extending the period with potential for sediment transport and erosion by ~ 6 months/year. Field measurements document Quaternary Alluvium as a modern source of fine sediment with grain size distributions characterized by 5 to 40% fine material. About 60% of an upland and 30% of a lowland study reach incised into this deposit exhibit bank erosion. During this study, the wet 2006 and relatively dry 2007 water years exhibited a range of total annual suspended sediment load spanning two orders of magnitude: ~ 108,500 kg/km2/year during 2006 and 5,950 kg/km2/year during 2007, only 5% of that during the previous year. Regional implications of this work are illustrated by the potential for a small tributary such as Willow Slough to contribute sediment – whereas large dams limit sediment supply from larger tributaries – to the Sacramento River and San Francisco Bay Delta and Estuary. This work is relevant to lowland agricultural river–floodplain systems globally in efforts to restore aquatic and riparian functions and where water quality

  6. Understanding the sources and mitigation potential of nitrous oxide in agriculture

    NASA Astrophysics Data System (ADS)

    Horwath, W. R.; Zhu, X.; Doane, T. A.; Burger, M.

    2014-12-01

    More than half of the global warming potential of GHG emissions from agriculture is attributed to nitrous oxide (N2O).. Many factors control the production and release of N2O from soils. In addition to fertilizer N, soil N, moisture and carbon availability control N2O emissions. In addition, a previously overlooked factor, iron, was recently found to be the most significant factor influencing N2O production. Controlled by soil and management factors, N2O production is attributed to multiple pathways, including ammonia oxidation (AO), denitrification, and abiotic chemical reactions. Ammonia oxidation or nitrifier activity N2O production, is a well known pathway, but it significance to total N2O production is also highly debated and soil conditions influencing its production are poorly understood. Studies in a variety of crops in California strongly suggest that this pathway contributes substantially to N2O emissions. It is well established that denitrification primarily occurs under O2- limiting conditions, while N2O produced from AO is also influenced by soil O2 content, with maximum production occurring at low O2 levels (~0.5%). Since emission of N2O can arise from both AO and denitrification activities at low O2 concentrations, it is difficult to discern the importance of each pathway under various soil conditions and management. Furthermore, both the N form and concentration are determinants of nitrifier N2O production. The nitrifier denitrification pathway has been shown to dominate over nitrifier nitrification and nitrification coupled denitrification pathways. Irrigation, rainfall, and fertilization events stimulate microbial activity, including AO and denitrification that produces N2O and although limited, these events contribute to the majority of annual emissions. This uncertainty and complexity surrounding N2O production pathways has hampered the development of practices to reduce N2O emissions. As agricultural production intensifies in developing

  7. Source and transport factors influencing storm phosphorus losses in agricultural catchments

    NASA Astrophysics Data System (ADS)

    Shore, Mairead; Jordan, Phil; Mellander, Per-Erik; kelly-quinn, Mary; Wall, David; Murphy, Paul; Melland, Alice

    2014-05-01

    The relative risk of diffuse phosphorus (P) loss from agricultural land was assessed in a well-drained arable catchment and a poorly-drained grassland catchment and in two nested basins within each catchment. This research investigated the relative control of hydrology and soil P on P losses between basins. Quick flow (QF) P losses (defined here as both concentrations and loads), monitored in stream flow during four storm events, were compared with a dynamic metric of transport risk (QF magnitude) and a static metric of critical source area (CSA) risk (extent of highly-connected poorly-drained soils with excess plant-available soil P). The potential for static transport metrics of soil connectivity and soil drainage class, to predict relative QF magnitudes and P losses between basins was also investigated. In basins with similar CSA risk but with contrasting QF magnitudes, mean TRP (total molybdate-reactive P) losses were consistently higher in the basins which had the highest QF magnitudes. This suggests that basin hydrology, rather than hydrology of high-P soils only, determined relative TRP losses between hydrologically contrasting basins. Furthermore, static transport metrics of soil connectivity and soil drainage class reliably discerned relative QF magnitudes and TRP losses between these basins. However, for two of the storm events (both occurring during the hydrologically active season), PP (particulate P) concentrations were frequently higher in basins which had the lowest QF magnitudes and may be attributed to a higher proportion of bare soil in these basins at these times as a result of their predominantly arable nature. In basins with similar hydrology, relative TRP and PP losses did not reflect trends in CSA risk or QF magnitude. The dynamics of TRP and PP losses and QF magnitude between these basins varied across storms, thus could not be predicted using static metrics. Where differences in hydrological dynamics were large, storm TRP losses were well

  8. Nitrate behaviors and source apportionment in an aquatic system from a watershed with intensive agricultural activities.

    PubMed

    Lu, Lu; Cheng, Hongguang; Pu, Xiao; Liu, Xuelian; Cheng, Qianding

    2015-01-01

    Nitrate pollution in aquatic systems caused by intensive agricultural activities is a serious problem in the Sanjiang Plain. In this study, a dual isotope approach (δ(15)N-NO3(-) and δ(18)O-NO3(-)) was employed to identify potential nitrate sources (atmospheric deposition, AD; NO3(-) derived from soil organic matter nitrification, NS; NO3(-) derived from chemical fertilizer nitrification, NF; and manure and sewage, M&S) and transformation processes occurring in the Abujiao River watershed located in the Sanjiang Plain. The Bayesian model (stable isotope analysis in R, SIAR) was utilized to apportion the contribution of the potential sources. In this watershed, the nitrate concentrations in the surface water were low (mean ± SD = 1.15 ± 0.84 mg L(-1)), and were greatly influenced by precipitation and land use conditions during the two sampling periods (the high flow period, September; the low flow period, November). On the contrary, in the ground water, high NO3(-) concentrations were observed (7.84 ± 5.83 mg L(-1)) and no significant temporal variation in NO3(-) was found during the sampling periods. The sampled water δ(18)O-NO3(-) values suggest that the nitrification process was not the main N cycling process, because most of the measured δ(18)O-NO3(-) values were above the expected δ(18)O-NO3(-) from nitrification throughout the sampling periods. Both the chemical and isotopic characteristics indicated that the signs of de-nitrification were absent in the surface water. However, significant de-nitrification processes were observed in the ground water for all sample periods. Results from the SIAR model showed that source contributions differed significantly during the two sampling periods. During the high flow period, chemical fertilizers and soil N fertilizer equally contributed to the major sources of nitrate in the surface water. In contrast, manure and sewage sources dominated the source contribution during the low flow period (November). This study

  9. A Sheath Model for Negative Ion Sources Including the Formation of a Virtual Cathode

    SciTech Connect

    McAdams, R.; King, D. B.; Surrey, E.

    2011-09-26

    A one dimensional model of the sheath between the plasma and the wall in a negative ion source has been developed. The plasma consists of positive ions, electrons and negative ions. The model takes into account the emission of negative ions from the wall into the sheath and thus represents the conditions in a caesiated ion source with surface production of negative ions. At high current densities of the emitted negative ions, the sheath is unable to support the transport of all the negative ions to the plasma and a virtual cathode is formed. This model takes this into account and allows the calculation of the transported negative ions across the sheath with the virtual cathode. The model has been extended to allow the linkage between plasma conditions at the sheath edge and the plasma to be made. Comparisons are made between the results of the model and experimental measurements.

  10. Source identification of PCDD/Fs in agricultural soils near to a Chinese MSWI plant through isomer-specific data analysis.

    PubMed

    Xu, Meng-Xia; Yan, Jian-Hua; Lu, Sheng-Yong; Li, Xiao-Dong; Chen, Tong; Ni, Ming-Jiang; Dai, Hui-Fen; Cen, Ke-Fa

    2008-04-01

    Isomer-specific data were investigated in order to identify the sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in agricultural soils, including Fluvo-aquic and paddy soils, in the vicinity of a Chinese municipal solid waste incineration (MSWI) plant. Homologue and isomer profiles of PCDD/Fs in soils were compared with those of potential sources, including combustion sources, i.e., MSWI flue gas and fly ash; and the impurities in agrochemicals, such as the pentachlorophenol (PCP), sodium pentachlorophenate (PCP-Na) and 1,3,5-trichloro-2-(4-nitrophenoxy) benzene (CNP). The results showed that the PCDD/F isomer profiles of combustion sources and agricultural soils were very similar, especially for PCDFs, although their homologue profiles varied, indicating that all the isomers within each homologue behave identically in the air and soil. Moreover, factor analysis of the isomer compositions among 33 soil samples revealed that the contamination of PCDD/Fs in agricultural soils near the MSWI plant were primarily influenced by the combustion sources, followed by the PCP/PCP-Na and CNP sources. This implication is consistent with our previous findings based on chemometric analysis of homologue profiles of soil and flue gas samples, and identifies PCP/PCP-Na as an additional important source of PCDD/Fs in the local area. This makes the similarities and differences of isomer profiles between Fluvo-aquic and paddy soils more explainable. It is, therefore, advisable to use isomer-specific data for PCDD/F source identifications where possible.

  11. Modeling of land use and reservoir effects on nonpoint source pollution in a highly agricultural basin

    USGS Publications Warehouse

    Wu, Yiping; Liu, Shu-Guang

    2012-01-01

    Nonpoint source (NPS) pollution is tightly linked to land use activities that determine the sources and magnitudes of pollutant loadings to stream water. The pollutant loads may also be alleviated within reservoirs because of the physical interception resulting from changed hydrological regimes and other biochemical processes. It is important but challenging to assess the NPS pollution processes with human effects due to the measurement limitations. The objective of this study is to evaluate the effects of human activities such as land uses and reservoir operation on the hydrological and NPS pollution processes in a highly agricultural area-the Iowa River Basin-using the Soil and Water Assessment Tool (SWAT). The evaluation of model performance at multiple sites reveals that SWAT can consistently simulate the daily streamflow, and monthly/annual sediment and nutrient loads (nitrate nitrogen and mineral phosphorus) in the basin. We also used the calibrated model to estimate the trap efficiencies of sediment (~78%) and nutrients (~30%) in the Coralville Reservoir within the basin. These non-negligible effects emphasize the significance of incorporating the sediment and nutrient removal mechanisms into watershed system studies. The spatial quantification of the critical NPS pollution loads can help identify hot-spot areas that are likely locations for the best management practices.

  12. Modeling of land use and reservoir effects on nonpoint source pollution in a highly agricultural basin.

    PubMed

    Wu, Yiping; Liu, Shuguang

    2012-09-01

    Nonpoint source (NPS) pollution is tightly linked to land use activities that determine the sources and magnitudes of pollutant loadings to stream water. The pollutant loads may also be alleviated within reservoirs because of the physical interception resulting from changed hydrological regimes and other biochemical processes. It is important but challenging to assess the NPS pollution processes with human effects due to the measurement limitations. The objective of this study is to evaluate the effects of human activities such as land uses and reservoir operation on the hydrological and NPS pollution processes in a highly agricultural area-the Iowa River Basin-using the Soil and Water Assessment Tool (SWAT). The evaluation of model performance at multiple sites reveals that SWAT can consistently simulate the daily streamflow, and monthly/annual sediment and nutrient loads (nitrate nitrogen and mineral phosphorus) in the basin. We also used the calibrated model to estimate the trap efficiencies of sediment (∼78%) and nutrients (∼30%) in the Coralville Reservoir within the basin. These non-negligible effects emphasize the significance of incorporating the sediment and nutrient removal mechanisms into watershed system studies. The spatial quantification of the critical NPS pollution loads can help identify hot-spot areas that are likely locations for the best management practices.

  13. Modeling of land use and reservoir effects on nonpoint source pollution in a highly agricultural basin.

    PubMed

    Wu, Yiping; Liu, Shuguang

    2012-09-01

    Nonpoint source (NPS) pollution is tightly linked to land use activities that determine the sources and magnitudes of pollutant loadings to stream water. The pollutant loads may also be alleviated within reservoirs because of the physical interception resulting from changed hydrological regimes and other biochemical processes. It is important but challenging to assess the NPS pollution processes with human effects due to the measurement limitations. The objective of this study is to evaluate the effects of human activities such as land uses and reservoir operation on the hydrological and NPS pollution processes in a highly agricultural area-the Iowa River Basin-using the Soil and Water Assessment Tool (SWAT). The evaluation of model performance at multiple sites reveals that SWAT can consistently simulate the daily streamflow, and monthly/annual sediment and nutrient loads (nitrate nitrogen and mineral phosphorus) in the basin. We also used the calibrated model to estimate the trap efficiencies of sediment (∼78%) and nutrients (∼30%) in the Coralville Reservoir within the basin. These non-negligible effects emphasize the significance of incorporating the sediment and nutrient removal mechanisms into watershed system studies. The spatial quantification of the critical NPS pollution loads can help identify hot-spot areas that are likely locations for the best management practices. PMID:22790209

  14. LCLS-II: Upgrade Plans for the Linac Coherent Light Source-Including New Scientific Opportunities

    NASA Astrophysics Data System (ADS)

    Schlotter, William; LCLS-II Team

    2015-03-01

    The Linac Coherent Light Source (LCLS) is planning a major upgrade that will provide revolutionary new scientific capabilities for exploring materials on the atomic and nano-scale with element specificity and ultrafast temporal resolution. The LCLS is an x-ray free electron laser with six experimental instruments accessible via a peer-reviewed proposal process. The upgraded LCLS-II facility will continuously deliver ultrafast x-ray pulses at repetition rates greater than 100kHz with photon energies tunable between 250 eV and 5 keV. The upgrade will also produce pulses with photon energies as high as 25 keV at a repetition rate of 120 Hz. These capabilities will enable new scientific methods that will revolutionize the study of highly correlated electron systems, magnetization dynamics and nanoscale fluctuations in soft matter to name a few. Expected capabilities and prospective experimental examples will be presented. The Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory. LCLS is an Office of Science User Facility operated for the U.S. Department of Energy Office of Science by Stanford University.

  15. A Description and Source Listing of Curriculum Materials in Agricultural Education, 1969-1970.

    ERIC Educational Resources Information Center

    American Vocational Association, Washington, DC. Agricultural Education Div.

    The purpose of this annotated bibliography is to provide teachers of vocational agriculture, agricultural supervisors, and agricultural teacher educators with information on current curriculum materials available to them. Classified according to the AGDEX filing system, the 163 references are grouped under the headings: (1) Field Crops, (2)…

  16. A Description and Source Listing of Curriculum Materials in Agricultural Education. 1972-73.

    ERIC Educational Resources Information Center

    American Vocational Association, Washington, DC. Agricultural Education Div.

    Listed are 246 curriculum material items in ten categories: field crops, horticulture, forestry, animal science, soils, diseases and pests, agricultural engineering, agricultural economics, agricultural occupations, and professional. Most materials are annotated and all are classified according to the AGPEX filing system. Bibliographic and…

  17. A Description and Source Listing of Curriculum Materials in Agricultural Education, 1970-1971.

    ERIC Educational Resources Information Center

    American Vocational Association, Washington, DC. Agricultural Education Div.

    To provide teachers of vocational agriculture, agricultural supervisors, and agricultural teacher educators with information on current curriculum materials available to them, this annotated bibliography presents 207 references classified according to the AGDEX filing system. Topics are: (1) Field Crops, (2) Horticulture, (3) Forestry, (4) Animal…

  18. The organic agricultural waste as a basic source of biohydrogen production

    NASA Astrophysics Data System (ADS)

    Sriwuryandari, Lies; Priantoro, E. Agung; Sintawardani, Neni; Astuti, J. Tri; Nilawati, Dewi; Putri, A. Mauliva Hada; Mamat, Sentana, Suharwadji; Sembiring, T.

    2016-02-01

    Biohydrogen production research was carried out using raw materials of agricultural organic waste that was obtained from markets around the Bandung city. The organic part, which consisted of agricultural waste material, mainly fruit and vegetable waste, was crushed and milled using blender. The sludge that produced from milling process was then used as a substrate for mixed culture microorganism as a raw material to produce biohydrogen. As much as 1.2 kg.day-1 of sludge (4% of total solid) was fed into bioreactor that had a capacity of 30L. Experiment was done under anaerobic fermentation using bacteria mixture culture that maintained at pH in the range of 5.6-6.5 and temperature of 25-30oC on semi-continuous mode. Parameters of analysis include pH, temperature, total solid (TS), organic total solid (OTS), total gas production, and hydrogen gas production. The results showed that from 4% of substrate resulted 897.86 L of total gas, which contained 660.74 L (73.59%) of hydrogen gas. The rate of hydrogen production in this study was 11,063 mol.L-1.h-1.

  19. Investigating the Sources and Dynamics of Dissolved Organic Matter in an Agricultural Watershed in California (U.S.A.)

    NASA Astrophysics Data System (ADS)

    Dyda, R. Y.; Hernes, P. J.; Spencer, R. G.; Ingrum, T. D.; Pellerin, B. A.; Bergamaschi, B. A.

    2007-12-01

    Dissolved organic matter (DOM) is ubiquitous and plays critical roles in nutrient cycling, aquatic food webs and numerous other biogeochemical processes. Furthermore, various factors control the quality and quantity of DOM, including land use, soil composition, in situ production, microbial uptake and assimilation and hydrology. As a component of DOM, dissolved organic carbon (DOC) has been recently identified as a drinking water constituent of concern due to its propensity to form EPA-regulated carcinogenic compounds when disinfected for drinking water purposes. Therefore, understanding the sources, cycling and modification of DOC across various landscapes is of direct relevance to a wide range of studies. The Willow Slough watershed is located in the Central Valley of California (U.S.A.) and is characterized by both diverse geomorphology as well as land use. The watershed drains approximately 425 km2 and is bordered by Cache and Putah Creeks to the north and south. The study area in the watershed includes the eastern portion of the foothills of the inner Coast Range and the alluvial plain and encompasses diverse land uses, including orchards, viticulture, dairy, pasture and natural grasslands. The Willow Slough watershed represents a unique opportunity to examine DOC dynamics through multiple land uses and hydrologic flow paths that are common throughout California. Preliminary data show that DOC concentrations at the watershed mouth peak during winter storms and also increase gradually throughout the summer months during the agricultural irrigation season. The increasing DOC concentrations during the summer months may result from agricultural runoff and/or primary production in channel. In addition, initial results using the chromophoric DOM (CDOM) absorption coefficient and spectral slope parameters indicate seasonal differences in the composition of the DOM. Spectral slopes decreased during both the summer irrigation season and winter storms relative to winter

  20. Nutrition in pregnancy: the argument for including a source of choline.

    PubMed

    Zeisel, Steven H

    2013-01-01

    Women, during pregnancy and lactation, should eat foods that contain adequate amounts of choline. A mother delivers large amounts of choline across the placenta to the fetus, and after birth she delivers large amounts of choline in milk to the infant; this greatly increases the demand on the choline stores of the mother. Adequate intake of dietary choline may be important for optimal fetal outcome (birth defects, brain development) and for maternal liver and placental function. Diets in many low income countries and in approximately one-fourth of women in high income countries, like the United States, may be too low in choline content. Prenatal vitamin supplements do not contain an adequate source of choline. For women who do not eat foods containing milk, meat, eggs, or other choline-rich foods, a diet supplement should be considered.

  1. Contribution of base flow to nonpoint source pollution loads in an agricultural watershed

    USGS Publications Warehouse

    Schilling, K.E.; Wolter, C.F.

    2001-01-01

    Nonpoint source pollution of surface water from overland flow, drainage tiles, and ground water discharge is a major cause of water quality impairment in Iowa. Nonpoint source pollution from base flow ground water was estimated in the Walnut Creek watershed by measuring chemical loads of atrazine, nitrate, chloride, and sulfate at 18 tributary creeks and 19 tiles. Loads were measured during a stable base flow period at creeks and files that discharged into Walnut Creek between two stream gauges. Chemical concentrations of atrazine (< 0.1-12 ??g/L), nitrate (0.1 to 15 mg/L, and chloride (1.5 to 26 mg/L) in water were similar for creek and tile samples. Water draining predominantly agricultural row crop areas had much higher concentrations than water draining restored prairie areas. Three methods were used to estimate base flow discharge in the watershed: (1) Darcy flux; (2) watershed discharge budget; and (3) discharge-drainage area; each yielded similar results (31.2 L/s to 62.3 L/s). Base flow loads to the main channel were estimated by subtracting the loads from the upstream gauge; creeks and tiles, from the total load measured at the downstream gauge station. Base flow concentration for atrazine ranged from 0.15 to 0.29 ??g/L and sulfate concentration ranged from 32 to 64 mg/L, whereas concentrations for nitrate and chloride were negative (-1 to -4 mg/L). Calculated base flow concentrations of atrazine and sulfate appeared to be reasonable estimates, but negative concentrations of nitrate and chloride imply either loss of chemical mass in the stream from upstream to downstream sampling points or measurement error. Load data suggest little contribution from base flow pollutants to Walnut Creek water quality, with most of the pollutant load derived from major tributary creeks. Results from this study have implications for determining total maximum daily loads in agricultural watersheds where contributions from point sources (creeks and tiles) can he used to

  2. Completed Research in Health, Physical Education, Recreation & Dance, Including International Sources. Volume 32-1990 Edition.

    ERIC Educational Resources Information Center

    Chamberlin, Craig, Ed.

    This compilation provides 256 abstracts of research completed in the areas of health, physical education, recreation, dance, and allied areas during 1989. Master's theses and doctoral dissertations are abstracted from institutions offering graduate programs in those fields. The volume includes an index to the abstracts in which references are…

  3. OpenOrb: Open-source asteroid orbit computation software including statistical ranging

    NASA Astrophysics Data System (ADS)

    Granvik, M.; Virtanen, J.; Oszkiewicz, D.; Muinonen, K.

    2009-01-01

    We are making an open-source asteroid orbit computation software package called OpenOrb publicly available. OpenOrb is built on a well-established Bayesian inversion theory, which means that it is to a large part complementary to orbit-computation packages currently available. In particular, OpenOrb is the first package that contains tools for rigorously estimating the uncertainties resulting from the inverse problem of computing orbital elements using scarce astrometry. In addition to the well-known least-squares method, OpenOrb also contains both Monte-Carlo (MC) and Markov-Chain MC (MCMC; Oszkiewicz et al. [2009]) versions of the statistical ranging method. Ranging allows the user to obtain sampled, non-Gaussian orbital-element probability-density functions and is therefore optimized for cases where the amount of astrometry is scarce or spans a relatively short time interval. Ranging-based methods have successfully been applied to a variety of different problems such as rigorous ephemeris prediction, orbital element distribution studies for transneptunian objects, the computation of invariant collision probabilities between near-Earth objects and the Earth, detection of linkages between astrometric asteroid observations within an apparition as well as between apparitions, and in the rigorous analysis of the impact of orbital arc length and/or astrometric uncertainty on the uncertainty of the resulting orbits. Tools for making ephemeris predictions and for classifying objects based on their orbits are also available in OpenOrb. As an example, we use OpenOrb in the search for candidate retrograde and/or high-inclination objects similar to 2008 KV42 in the known population of transneptunian objects that have an observational time span shorter than 30 days.

  4. Agricultural non-point source pollution in the Western Coal Field region of Kentucky

    SciTech Connect

    Snell, J.D.; Sendlein, L.V.A. . Dept. of Geological Sciences)

    1993-03-01

    As part of a general plan to characterize the extent of agricultural non-point source pollution in the different physiographic regions of Kentucky, two sites located in the Western Coal Field Physiographic provinces representing farmland drained by field tiles were chosen for ground water monitoring. These two sites are similar geologically, but the levels of Nitrate-N have proven to be drastically different between the two areas. A total of 24 wells and 3 lysimeters were installed at the two sites in three nested areas. Although both study sites are located in lowland valleys in fine grained lacustrine deposits, the materials at the Hopkins County site are slightly coarser grained. The wells in Hopkins County, with the exception of the two in the riparian zone, yield water consistently and substantially higher in Nitrate-N than wells in Daviess County. The Nitrate-N levels regularly hover near or exceed the EPA limit in Hopkins County, whereas the levels in Daviess County are near and in most cases far below the 0.53 ppm background level for the region. Pesticide concentrations are minor in both areas with small spikes of contamination noted in shallow wells shortly after application. The concentration of both the pesticides and the Nitrate-N drops off quickly with depth in both counties yielding relatively clean water below the lacustrine deposits.

  5. Nonpoint-source agricultural hazard index: a case study of the province of cremona, Italy.

    PubMed

    Trevisan, M; Padovani, L; Capri, E

    2000-11-01

    This paper reports the results of a study aimed at the evaluation of the hazard level of farming activities in the province of Cremona, Italy, with particular reference to groundwater. The applied methodology employs a parametric approach based on the definition of potential hazard indexes (nonpoint-source agricultural hazard indexes, NPSAHI). Two categories of parameters were considered: the hazard factors (HF), which represent all farming activities that cause or might cause an impact on groundwater (use of fertilizers and pesticides, application of livestock and poultry manure, food industry wastewater, and urban sludge), and the control factors (CF), which adapt the hazard factor to the characteristics of the site (geographical location, slope, agronomic practices, and type of irrigation). The hazard index (HI) can be calculated multiplying the hazard factors by the control factors and, finally, the NPSAHI are obtained dividing HI into classes on a percentile basis using a scale ranging from 1 to 10. Organization, processing, and display of all data layers were performed using the geographical information system (GIS) ArcView and its Spatial Analyst extension. Results show that the potential hazard of groundwater pollution by farming activities in the province of Cremona falls mainly in the fifth class (very low hazard).

  6. Unaccounted variability in NH3 agricultural sources detected by IASI contributing to European spring haze episode

    NASA Astrophysics Data System (ADS)

    Fortems-Cheiney, A.; Dufour, G.; Hamaoui-Laguel, L.; Foret, G.; Siour, G.; Van Damme, M.; Meleux, F.; Coheur, P.-F.; Clerbaux, C.; Clarisse, L.; Favez, O.; Wallasch, M.; Beekmann, M.

    2016-05-01

    Ammonia (NH3), whose main source in the troposphere is agriculture, is an important gaseous precursor of atmospheric particulate matter (PM). We derived daily ammonia emissions using NH3 total columns measured from the Infrared Atmospheric Sounding Interferometer (IASI) on board Metop-A, at a relatively high spatial resolution (grid cell of 0.5° × 0.5°). During the European spring haze episodes of 24-31 March 2012 and 8-15 March 2014, IASI reveals NH3 total column magnitudes highlighting higher NH3 emissions over central Europe (especially over Germany, Czech Republic, and eastern France) from the ones provided by the European reference European Monitoring and Evaluation Programme inventory. These ammonia emissions exhibit in addition a large day-to-day variability, certainly due to spreading practices. The increase of NH3 emissions in the model, that reaches +300% locally, leads to an increase of both NH3 and PM2.5 surface concentrations and allows for a better comparison with independent measurements (in terms of bias, root-mean-square error, and correlation). This study suggests that there are good prospects for better quantifying NH3 emissions by atmospheric inversions.

  7. Developing unique tracers to distinguish nutrient contributions from agriculture and wastewater sources in the Choptank River and Anacostia River watersheds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eutrophication is a major problem for the Chesapeake Bay ecosystem. The efficacy of the restoration efforts implemented is restricted by the inability to differentiate nutrient sources. This study assessed the use of stable tracers in order to discriminate between urban and agricultural nutrient sou...

  8. Studies by the U.S. Geological Survey on sources, transport, and fate of agricultural chemicals

    USGS Publications Warehouse

    Capel, Paul D.; Hamilton, Pixie A.; Erwin, Martha L.

    2004-01-01

    Information from these studies will help with decision-making related to chemical use, conservation, and other farming practices that are used to reduce runoff of agricultural chemicals and sediment from fields. This information also will benefit the U.S. Environmental Protection Agency, the Department of Agriculture, local and regional water managers, and agricultural chemical manufacturers who are involved in managing chemical use and pesticide registration.

  9. Integrating different knowledge sources and disciplines for practical applications in Forest and Agricultural Engineering

    NASA Astrophysics Data System (ADS)

    Guzmán, Gema; Castillo, Carlos; Taguas, Encarnación

    2013-04-01

    One of the aims of 'The Bologna Process' is to promote among the students the acquisition of practical, social and creative skills to face real-life situations and to solve the difficulties they might find during their professional life. It involves an important change in the educational system, from a traditional approach focused on teaching, towards a new one that encourages learning. Under this context, University teaching implies the design of activities addressed to the dissemination of "know-how" to solve different problems associated with two technical disciplines: Forest and Agricultural Engineering. This study presents a preliminary experience where a group of information and communication technologies (ICT) such as, audiovisual resources (videos, reports and photo gallery), virtual visits to blogs and interactive activities have been used to provide a comprehensive knowledge of the environmental and sociocultural components of the landscape in order to facilitate the decision-making process in the engineering project context . With these tools, the students must study and characterize all these aspects in order to justify the chosen solutions and the project design. This approach was followed in the analysis of the limiting factors of practical cases in projects about forestation, landscape restoration and hydrological planning. This communication shows how this methodology has been applied in Forest and Agricultural Engineering and the students' experience with these innovative tools. The use of ICTs involved a friendly framework that stimulated students' interest and made subjects more attractive, since it allowed to assess the complex relationships between landscape, history and economy. Furthermore, this type of activities promotes the interdisciplinary training and the acquisition of creative and autonomous skills which are not included in many cases into the main objectives of the subjects.

  10. Quantifying sediment sources in a lowland agricultural catchment pond using (137)Cs activities and radiogenic (87)Sr/(86)Sr ratios.

    PubMed

    Le Gall, Marion; Evrard, Olivier; Foucher, Anthony; Laceby, J Patrick; Salvador-Blanes, Sébastien; Thil, François; Dapoigny, Arnaud; Lefèvre, Irène; Cerdan, Olivier; Ayrault, Sophie

    2016-10-01

    Soil erosion often supplies high sediment loads to rivers, degrading water quality and contributing to the siltation of reservoirs and lowland river channels. These impacts are exacerbated in agricultural catchments where modifications in land management and agricultural practices were shown to accelerate sediment supply. In this study, sediment sources were identified with a novel tracing approach combining cesium ((137)Cs) and strontium isotopes ((87)Sr/(86)Sr) in the Louroux pond, at the outlet of a lowland cultivated catchment (24km(2), Loire River basin, France) representative of drained agricultural areas of Northwestern Europe. Surface soil (n=36) and subsurface channel bank (n=17) samples were collected to characterize potential sources. Deposited sediment (n=41) was sampled across the entire surface of the pond to examine spatial variation in sediment deposits. In addition, a 1.10m sediment core was sampled in the middle of the pond to reconstruct source variations throughout time. (137)Cs was used to discriminate between surface and subsurface sources, whereas (87)Sr/(86)Sr ratios discriminated between lithological sources. A distribution modeling approach quantified the relative contribution of these sources to the sampled sediment. Results indicate that surface sources contributed to the majority of pond (μ 82%, σ 1%) and core (μ 88%, σ 2%) sediment with elevated subsurface contributions modeled near specific sites close to the banks of the Louroux pond. Contributions of the lithological sources were well mixed in surface sediment across the pond (i.e., carbonate sediment contribution, μ 48%, σ 1% and non-carbonate sediment contribution, μ 52%, σ 3%) although there were significant variations of these source contributions modeled for the sediment core between 1955 and 2013. These fluctuations reflect both the progressive implementation of land consolidation schemes in the catchment and the eutrophication of the pond. This original sediment

  11. Quantifying sediment sources in a lowland agricultural catchment pond using (137)Cs activities and radiogenic (87)Sr/(86)Sr ratios.

    PubMed

    Le Gall, Marion; Evrard, Olivier; Foucher, Anthony; Laceby, J Patrick; Salvador-Blanes, Sébastien; Thil, François; Dapoigny, Arnaud; Lefèvre, Irène; Cerdan, Olivier; Ayrault, Sophie

    2016-10-01

    Soil erosion often supplies high sediment loads to rivers, degrading water quality and contributing to the siltation of reservoirs and lowland river channels. These impacts are exacerbated in agricultural catchments where modifications in land management and agricultural practices were shown to accelerate sediment supply. In this study, sediment sources were identified with a novel tracing approach combining cesium ((137)Cs) and strontium isotopes ((87)Sr/(86)Sr) in the Louroux pond, at the outlet of a lowland cultivated catchment (24km(2), Loire River basin, France) representative of drained agricultural areas of Northwestern Europe. Surface soil (n=36) and subsurface channel bank (n=17) samples were collected to characterize potential sources. Deposited sediment (n=41) was sampled across the entire surface of the pond to examine spatial variation in sediment deposits. In addition, a 1.10m sediment core was sampled in the middle of the pond to reconstruct source variations throughout time. (137)Cs was used to discriminate between surface and subsurface sources, whereas (87)Sr/(86)Sr ratios discriminated between lithological sources. A distribution modeling approach quantified the relative contribution of these sources to the sampled sediment. Results indicate that surface sources contributed to the majority of pond (μ 82%, σ 1%) and core (μ 88%, σ 2%) sediment with elevated subsurface contributions modeled near specific sites close to the banks of the Louroux pond. Contributions of the lithological sources were well mixed in surface sediment across the pond (i.e., carbonate sediment contribution, μ 48%, σ 1% and non-carbonate sediment contribution, μ 52%, σ 3%) although there were significant variations of these source contributions modeled for the sediment core between 1955 and 2013. These fluctuations reflect both the progressive implementation of land consolidation schemes in the catchment and the eutrophication of the pond. This original sediment

  12. Characterizing the ozone formation potential of agricultural sources in California's San Joaquin Valley: A computational and experimental approach

    NASA Astrophysics Data System (ADS)

    Howard, Cody Jerome

    The global pattern of expanding urban centers and increasing agricultural intensity is leading to more frequent interactions between air pollution emissions from urban and agricultural sources. The confluence of these emissions that traditionally have been separated by hundreds of kilometers is creating new air quality challenges in numerous regions across the United States. An area of particular interest is California's San Joaquin Valley (SJV), which has an agricultural output higher than many countries, a rapidly expanding human population, and ozone concentrations that are already higher than many dense urban areas. New regulations in the SJV restrict emissions of reactive organic gases (ROG) from animal sources in an attempt to meet Federal and State ozone standards designed to protect human health. A transportable "smog" chamber was developed and tested to directly measure the ozone formation potential of a variety of agricultural emissions in representative urban and rural atmospheres. After validation of the experimental procedure, four animal types were examined: beef cattle, dairy cattle, swine, and poultry, as well as six commonly used animal feeds: cereal silage (wheat grain and oat grain), alfalfa silage, corn silage, high moisture ground corn, almond shells, almond hulls, and total mixed ration. The emitted ROG composition was also measured so that the theoretical incremental reactivity could be calculated for a variety of atmospheres and directly compared with the measured ozone formation potential (OFP) under the experimental conditions. A computational model was created based on a modified form of the Caltech Atmospheric Chemistry Mechanism and validated against experimental results. After validation, the computational model was used to predict OFP across a range of NOx and ROG concentrations. The ROG OFP measurements combined with adjusted agricultural ROG emissions inventory estimates were used to predict the actual ozone production in the SJV

  13. Sulphate leaching from diffuse agricultural and forest sources in a large central European catchment during 1900-2010.

    PubMed

    Kopáček, Jiří; Hejzlar, Josef; Porcal, Petr; Posch, Maximilian

    2014-02-01

    Using dynamic, mass budget, and empirical models, we quantified sulphate-sulphur (SO4-S) leaching from soils in a large central European catchment (upper Vltava river, Czech Republic) over a 110-year period (1900-2010). SO4-S inputs to soils with synthetic fertilisers and atmospheric deposition increased in the 1950s-1980s, then rapidly decreased (~80%), and remained low since the middle 1990s. The proportion of drained agricultural land rapidly increased from 4 to 43% between the 1950s and 1990s; then the draining ability of the system slowly decreased due to its ageing. Sulphate concentrations in the Vltava exhibited similar trends as the external SO4-S inputs, suggesting that they could be explained by changes in atmospheric and fertiliser S inputs. The available data and modelling, however, showed that (i) internal SO4-S sources (mineralization of soil organic S in the drained agricultural land), (ii) a hysteresis in SO4-S leaching from forest soils (a net S retention at the high S inputs and then a net release at the lowered inputs), and (iii) hydrology must be taken into account. An empirical model was then employed, based on parameters representing hydrology (discharge), external SO4-S sources (inputs by synthetic fertilisers and atmospheric deposition), and internal SO4-S sources (mineralization related to soil drainage). The model explained 84% of the observed variability in annual SO4-S concentrations in the Vltava river during 1900-2010 and showed that forest soils were a net sink (105 kg ha(-1)) while agricultural land was a net source (55 kg ha(-1)) of SO4-S during 1960-2010. In the late 1980s, forest soils changed from a sink to a source of S, and the present release of SO4-S accumulated in forest soils thus delays recovery of surface waters from acidification, while S losses from agricultural soils increase the risk of future S deficiency in S-demanding crops.

  14. 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...

  15. PROBABILISTIC ASSESSMENT OF GROUNDWATER VULNERABILITY TO NONPOINT SOURCE POLLUTION IN AGRICULTURAL WATERSHEDS

    EPA Science Inventory

    This paper presents a probabilistic framework for the assessment of groundwater pollution potential by pesticides in two adjacent agricultural watersheds in the Mid-Altantic Coastal Plain. Indices for estimating streams vulnerability to pollutants' load from the surficial aquifer...

  16. National, holistic, watershed-scale approach to understand the sources, transport, and fate of agricultural chemicals

    USGS Publications Warehouse

    Capel, P.D.; McCarthy, K.A.; Barbash, J.E.

    2008-01-01

    This paper is an introduction to the following series of papers that report on in-depth investigations that have been conducted at five agricultural study areas across the United States in order to gain insights into how environmental processes and agricultural practices interact to determine the transport and fate of agricultural chemicals in the environment. These are the first study areas in an ongoing national study. The study areas were selected, based on the combination of cropping patterns and hydrologic setting, as representative of nationally important agricultural settings to form a basis for extrapolation to unstudied areas. The holistic, watershed-scale study design that involves multiple environmental compartments and that employs both field observations and simulation modeling is presented. This paper introduces the overall study design and presents an overview of the hydrology of the five study areas. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

  17. Characteristic and potential sources of polychlorinated dibenzo-P-dioxins and dibenzofurans in agricultural soils in Beijing, China.

    PubMed

    Li, Wei; Li, Chaoqin; Chen, Zuosheng; Cai, Zongwei

    2014-09-01

    Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in 25 background and 80 agricultural soil samples collected from 21 sites in Beijing, China. The levels of PCDD/Fs in the north agricultural soils were low (0.15-0.58 ng international toxic equivalent quantity [I-TEQ]/kg), which were comparable with those of the background soils (0.091-0.35 ng I-TEQ/kg). In the southern agricultural soils, however, concentrations were several times higher (0.27-3.3 ng I-TEQ/kg). Comparison of PCDD/Fs congener compositions between possible sources and samples indicated that agricultural soils in Beijing had not been contaminated by the 3 main PCDD/F contamination sources in China--ferrous and nonferrous metal, waste incineration, and power generation. They had, however, been slightly contaminated by the impurities of some organochlorine pesticides, such as sodium pentachlorophenate, and by open burning of biomass, vehicle exhaust, atmospheric deposition, sediment, and sewage sludge. These results have been supported by the principal components analysis.

  18. [Three patterns of interaction between soil and non-point source P-pollutants in agricultural watershed].

    PubMed

    Wang, Xia-hui; Yin, Cheng-qing; Yan, Xiao; Shan, Bao-qing; Wang, Wei-dong

    2004-07-01

    Typical agricultural watershed was selected to study the interactions between soil matrix and non-point source P-pollutants in surface runoff under simulative conditions. The soil samples were taken in different spatial locations in this watershed and were under different degree of human disturbance. The results showed that the interactions between different soil matrix and phosphorus could be divided into three patterns:retention, release and combination of retention and release. Soil of retention pattern has strong adsorption capacity of phosphate and will retain phosphorus from polluted runoff. Soil of release pattern has significant desorption capacity of phosphate and will release phosphorus to the runoff. Soil of retention and release combination pattern will retain or release phosphorus according to the phosphate concentration in the polluted runoff. These results showed that soil matrix in different spatial locations in the agricultural watershed have different ecological functions and environmental values under the processing of natural conditions and human disturbance. From the view of occurrence of non-point source pollution, these soils could become the sink of pollutants as well as the source of pollutants. Under some conditions, there has a conversion between sink and source of them. These results are valuable for control of non-point source pollution on watershed level, identification of key source area of pollutants and improvement of efficiency of control measures.

  19. Assessment of sources and fate of nitrate in shallow groundwater of an agricultural area by using a multi-tracer approach.

    PubMed

    Pastén-Zapata, Ernesto; Ledesma-Ruiz, Rogelio; Harter, Thomas; Ramírez, Aldo I; Mahlknecht, Jürgen

    2014-02-01

    Nitrate isotopic values are often used as a tool to understand sources of contamination in order to effectively manage groundwater quality. However, recent literature describes that biogeochemical reactions may modify these values. Therefore, data interpretation is difficult and often vague. We provide a discussion on this topic and complement the study using halides as comparative tracers assessing an aquifer underneath a sub-humid to humid region in NE Mexico. Hydrogeological information and stable water isotopes indicate that active groundwater recharge occurs in the 8000km(2) study area under present-day climatic and hydrologic conditions. Nitrate isotopes and halide ratios indicate a diverse mix of nitrate sources and transformations. Nitrate sources include organic waste and wastewater, synthetic fertilizers and soil processes. Animal manure and sewage from septic tanks were the causes of groundwater nitrate pollution within orchards and vegetable agriculture. Dairy activities within a radius of 1,000 m from a sampling point significantly contributed to nitrate pollution. Leachates from septic tanks caused nitrate pollution in residential areas. Soil nitrogen and animal waste were the sources of nitrate in groundwater under shrubland and grassland. Partial denitrification processes helped to attenuate nitrate concentration underneath agricultural lands and grassland, especially during summer months. PMID:24200723

  20. Assessment of sources and fate of nitrate in shallow groundwater of an agricultural area by using a multi-tracer approach.

    PubMed

    Pastén-Zapata, Ernesto; Ledesma-Ruiz, Rogelio; Harter, Thomas; Ramírez, Aldo I; Mahlknecht, Jürgen

    2014-02-01

    Nitrate isotopic values are often used as a tool to understand sources of contamination in order to effectively manage groundwater quality. However, recent literature describes that biogeochemical reactions may modify these values. Therefore, data interpretation is difficult and often vague. We provide a discussion on this topic and complement the study using halides as comparative tracers assessing an aquifer underneath a sub-humid to humid region in NE Mexico. Hydrogeological information and stable water isotopes indicate that active groundwater recharge occurs in the 8000km(2) study area under present-day climatic and hydrologic conditions. Nitrate isotopes and halide ratios indicate a diverse mix of nitrate sources and transformations. Nitrate sources include organic waste and wastewater, synthetic fertilizers and soil processes. Animal manure and sewage from septic tanks were the causes of groundwater nitrate pollution within orchards and vegetable agriculture. Dairy activities within a radius of 1,000 m from a sampling point significantly contributed to nitrate pollution. Leachates from septic tanks caused nitrate pollution in residential areas. Soil nitrogen and animal waste were the sources of nitrate in groundwater under shrubland and grassland. Partial denitrification processes helped to attenuate nitrate concentration underneath agricultural lands and grassland, especially during summer months.

  1. Poultry litter ash as a potential phosphorus source for agricultural crops.

    PubMed

    Codling, Eton E; Chaney, Rufus L; Sherwell, John

    2002-01-01

    Maryland will impose restrictions on poultry litter application to soils with excessive P by the year 2005. Alternative uses for poultry litter are being considered, including burning as a fuel to generate electricity. The resulting ash contains high levels of total P, but the availability for crop uptake has not been reported. Our objective was to compare the effectiveness of poultry litter ash (PLA) and potassium phosphate (KP) as a P source for wheat (Triticum aestivum L.) in acidic soils, without and with limestone application. Two acidic soils (pH 4.25 and 4.48) were studied, unlimed or limed to pH 6.5 before cropping. The PLA and KP were applied at 0, 39, and 78 kg P ha(-1), after which wheat was grown. Limestone significantly increased wheat yield, but the P sources without limestone did not. The two P sources were not significantly different as P fertilizer. At the 78 kg P ha(-1) rate, wheat shoot-P concentrations were 1.10 and 1.12 g kg(-1) for the PLA treatment compared with 0.90 and 0.89 g kg(-1) for KP in the nonlimed and limed soils, respectively. Trace element concentrations in wheat shoots from the PLA treatment were less than or equal to KP and the control. The low levels of water-soluble P and metals in the soils and the low metal concentrations in wheat suggest that PLA is an effective P fertilizer. Further studies are needed to determine the optimum application rate of PLA as a P fertilizer.

  2. Agriculture: A source of raw materials for industrial purposes the French strategy

    SciTech Connect

    Mauguin, P.; Gaouyer, J.P.; Labrousse, S.

    1995-11-01

    Creating new value-added products from agricultural and forestry biomass can present opportunities for diversifying industry, preserving agricultural activities and reinvigorating exploitation of forests. Stimulating new markets for agriculture and forestry products is strategically important for France, in order to cushion the effects of the reform of the European Common Policy (CAP), while maintaining the commitments assessed at the Rio Coference. The promotion of new markets should constitute a major vector for rural development, by marking use of agricultural lands no longer needed for food crops due to the glut of foodstuffs on the market. In the next few years, energy uses of biomass should help hold down greenhouse gas emissions, by regulating and storing CO{sub 2}. For each of these markets, whether for energy uses (solid, liquid or gaseous fuels) or for other applications, the first priority is to match prices and specifications of the fossil fuels that are to be deplaced, with minimum impact on the environment. To match these goals, the French government has launched a new research group, Agriculture for Chemicals and Energy (AGRICE). AGRICE has been set up for a renewable five years period. Its members are: Agriculture, Industry, Research and Environment departments; the Institut National de la Recherche Agronomique (INRA), the Institut Francais due Petrole (IFP), the French Agency for Environment and Energy (Ademe); Wheat producers, Beet growers, and oil seed producers; and Rhone Poulenc (chemicals), TOTAL (oil company). In 1995, AGRICE will have a 40 Millions FFrancs from public funds, supplemented by 25 Millions FFrancs from business and trade groups.

  3. Sediment sources in a small agricultural catchment: A composite fingerprinting approach based on the selection of potential sources

    NASA Astrophysics Data System (ADS)

    Zhou, Huiping; Chang, Weina; Zhang, Longjiang

    2016-08-01

    Fingerprinting techniques have been widely used as a reasonable and reliable means for investigating sediment sources, especially in relatively large catchments in which there are significant differences in surface materials. However, the discrimination power of fingerprint properties for small catchments, in which the surface materials are relatively homogeneous and human interference is marked, may be affected by fragmentary or confused source information. Using fingerprinting techniques can be difficult, and there is still a need for further studies to verify the effectiveness of such techniques in these small catchments. A composite fingerprinting approach was used in this study to investigate the main sources of sediment output, as well as their relative contributions, from a small catchment (30 km2) with high levels of farming and mining activities. The impact of the selection of different potential sediment sources on the derivation of composite fingerprints and its discrimination power were also investigated by comparing the results from different combinations of potential source types. The initial source types and several samples that could cause confusion were adjusted. These adjustments improved the discrimination power of the composite fingerprints. The results showed that the composite fingerprinting approach used in this study had a discriminatory efficiency of 89.2% for different sediment sources and that the model had a mean goodness of fit of 0.90. Cultivated lands were the main sediment source. The sediment contribution of the studied cultivated lands ranged from 39.9% to 87.8%, with a mean of 76.6%, for multiple deposited sediment samples. The mean contribution of woodlands was 21.7%. Overall, the sediment contribution from mining and road areas was relatively low. The selection of potential sources is an important factor in the application of fingerprinting techniques and warrants more attention in future studies, as is the case with other

  4. LANDSCAPE INFLUENCES ON NON-POINT SOURCED NUTRIENTS FOR AGRICULTURAL WATERSHEDS IN OHIO

    EPA Science Inventory

    In stream nutrient concentrations for a set of 35 small agricultural subwatersheds in southwestern Ohio have been monitored with respect to both water quality and biological integrity measures over a five year period. The dominant land cover in all of these subwatersheds is row ...

  5. A Description and Source Listing of Curriculum Materials in Agricultural Education, 1971-1972.

    ERIC Educational Resources Information Center

    American Vocational Association, Washington, DC. Agricultural Education Div.

    Members of the Curriculum Materials Committee collect materials available to them prior to each American Vocational Association Meeting. The resulting bibliography contains current, non-commercial materials developed by persons in vocational education in agriculture for use in that field, but of interest beyond the state in which it was developed.…

  6. A DESCRIPTION AND SOURCE LISTING OF PROFESSIONAL INFORMATION IN AGRICULTURAL EDUCATION, 1963-64.

    ERIC Educational Resources Information Center

    SLEDGE, GEORGE W.; AND OTHERS

    BRIEF ANNOTATIONS ARE GIVEN FOR MANY OF THE 107 REFERENCES LISTED UNDER THE FOLLOWING CATEGORIES -- (1) ADULT EDUCATION, (2) AGRICULTURAL ENGINEERING, (3) ANIMAL SCIENCE, (4) CURRICULUM DEVELOPMENT AND CURRICULUM IN CROPS, ENTOMOLOGY, FARM MANAGEMENT, FARM MECHANICS, AND LIVESTOCK, (5) FARM BUSINESS MANAGEMENT AND MARKETING, (6) FORESTRY, (7)…

  7. 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...

  8. Chemical characteristics and source apportionment of PM2.5 during the harvest season in eastern China's agricultural regions

    NASA Astrophysics Data System (ADS)

    Li, Jianfeng; Song, Yu; Mao, Yi; Mao, Zhichun; Wu, Yusheng; Li, Mengmeng; Huang, Xin; He, Qichao; Hu, Min

    2014-08-01

    To determine the contribution of the open burning of wheat straw residues to local PM2.5 during the harvest season of June 2013, PM2.5 was sampled in an agricultural region in eastern China. The sampling site was approximately 1 km from the nearest wheat field. Chemical compositions were analyzed, and source apportionment was undertaken using the positive matrix factorization model. The average PM2.5 concentration was 110.7 μg/m3, containing 36.4 μg/m3 organics, 7.3 μg/m3 EC, 6.0 μg/m3 potassium (K) and 4.9 μg/m3 chloride ion (Cl-). The sampling period was divided into three phases: the pre-local-burning phase (Phase 1), the local-burning phase (Phase 2) and the post-local-burning phase (Phase 3). In Phase 2, the concentrations of PM2.5 and the organics, EC, K and Cl- in PM2.5 were 163.6 μg/m3, 59.0 μg/m3, 12.2 μg/m3, 11.0 μg/m3 and 10.8 μg/m3, respectively, which were all remarkably higher than in both Phase 1 and Phase 3. Eight sources of PM2.5 were determined, including two types of wheat residue burning sources, which showed a significant difference in Cl- content. The atmospheric relative humidity (RH) and the aging process of PM2.5 might be the causes: only fresh particulate emissions from wheat residue burning could feature high-concentration Cl- under high RH conditions. In Phase 2, wheat residue burning contributed 51.3% of PM2.5, 75.8% of OC, 74.5% of EC, 90.1% of K and 104.1% of Cl-. These percentages were lower in Phases 1 and 3 than in Phase 2. Wheat residue burning caused such severe air pollution that it's necessary to prohibit the open burning of crop residues in order to protect public health and the environment.

  9. 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.

  10. Degradation State, Sources, and Reactivity of Dissolved Organic Matter from an Amino Acid Time Series in an Agricultural Watershed

    NASA Astrophysics Data System (ADS)

    Matiasek, S. J.; Pellerin, B. A.; Spencer, R. G.; Bergamaschi, B. A.; Hernes, P.

    2015-12-01

    A detailed time series of dissolved amino acids was obtained in an agricultural watershed in the northern Central Valley, California, USA to investigate the roles of hydrologic and seasonal changes on the composition of dissolved organic matter (DOM). Total hydrolysable amino acid (THAA) concentrations ranged from 0.55 to 9.96 μM (mean 3.76 ± 1.80 μM) and not only peaked with discharge during winter storms, but also remained elevated throughout the irrigation season when discharge was low. Summer irrigation was a critical hydrologic regime for DOM cycling, since it mobilized DOM similar in concentration and reactivity to DOM released during winter storms for an extended period of time, with the largest amino acid contributions to the dissolved organic carbon (DOC) and the dissolved organic nitrogen (DON) pools (3.4 ‒ 3.7 % DOC-AA, 17.4 ‒ 22.5 % DON-AA), the largest proportion of basic amino acids (B/(B+A) = 0.19 ‒ 0.22), and the largest degradation index values (mean 1.37 ± 0.96). The mole percent of non-protein amino acids, commonly considered as an indicator of microbial degradation, decreased with DOM processing and was highest during summer (mean 4.1 ± 1.1%). A lack of correlation between THAA concentrations and UV-Vis absorbance and fluorescence proxies (including "protein-like" fluorophores B and T) indicated that optical properties may be limited in representing amino acid dynamics in this system. A new parameter for DOM processing derived from trends in individual amino acids demonstrated strong potential for inferring the extent of DOM degradation in freshwater systems. The biogeochemical relevance of irrigation practices is heightened by timing, since the additional export of reactive DOM coincides with enhanced downstream DOM processing in the Sacramento-San Joaquin River Delta, a critical habitat for endangered species serving as water source for 25 million Californians.

  11. Comparing source of agricultural contact water and the presence of fecal indicator organisms on the surface of 'juliet' grape tomatoes.

    PubMed

    Pahl, Donna M; Telias, Adriana; Newell, Michael; Ottesen, Andrea R; Walsh, Christopher S

    2013-06-01

    Consumption of fresh tomatoes (Solanum lycopersicum) has been implicated as the cause of several foodborne illness outbreaks in the United States, most notably in cases of salmonellosis. How the levels of fecal indicator organisms (FIOs) in water relate to the counts of these microorganisms on the tomato fruit surface is unknown, although microbial water quality standards exist for agricultural use. This study utilized four types of FIOs currently and historically used in microbial water quality standards (Enterobacteriaceae, total coliforms, fecal coliforms, and Escherichia coli) to monitor the water quality of two surface ponds and a groundwater source. The groundwater tested contained significantly lower counts of all FIOs than the two surface water sources (P < 0.05). Considerable variability in bacterial counts was found in the surface water sources over the course of the season, perhaps explained by environmental variables, such as water temperature, pH, precipitation, and air temperature (R(2) of 0.13 to 0.27). We also monitored the fruit surface of grape tomatoes treated with overhead applications of the different water sources over the 2009 and 2010 growing seasons. The type of water source and time of year significantly affected the populations of FIOs in irrigation water (P < 0.05). Despite up to 5-log differences in fecal coliforms and 3-log differences in E. coli between the water sources, there was little difference in the populations measured in washes taken from tomato fruits. This lack of association between the aforementioned FIOs present in the water samples and on the tomato fruit surface demonstrates the difficulty in developing reliable metrics needed for testing of agricultural water to ensure the effectiveness of food safety programs.

  12. Initial results of a full kinetic simulation of RF H{sup −} source including Coulomb collision process

    SciTech Connect

    Mochizuki, S.; Shibata, T.; Nishida, K.; Hatayama, A.; Mattei, S.; Lettry, J.

    2015-04-08

    In order to evaluate Electron Energy Distribution Function (EEDF) more correctly for radio frequency inductively coupled plasma (RF-ICP) in hydrogen negative ion sources, the Electromagnetic Particle-In-Cell (EM-PIC) simulation code has been improved by taking into account electron-electron Coulomb collision. Binary collision model is employed to model Coulomb collision process and we have successfully modeled it. The preliminary calculation including Coulomb collision has been done and it is shown that Coulomb collision doesn’t have significant effects under the condition: electron density n{sub e} ∼ 10{sup 18} m{sup −3} and high gas pressure p{sub H{sub 2}} = 3 Pa, while it is necessary to include Coulomb collision under high electron density and low gas pressure conditions.

  13. Distribution, enrichment and principal component analysis for possible sources of naturally occurring and anthropogenic radionuclides in the agricultural soil of Punjab state, India.

    PubMed

    Kumar, Ajay; Joshi, Vikram M; Mishra, Manish K; Karpe, Rupali; Rout, Sabyasachi; Narayanan, Usha; Tripathi, Raj M; Singh, Jaspal; Kumar, Sanjeev; Hegde, Ashok G; Kushwaha, Hari S

    2012-06-01

    Enrichment factor (EF) of elements including geo-accumulation indices for soil quality and principal component analysis (PCA) were used to identify the contributions of the origin of sources in the studied area. Results of (40)K, (137)Cs, (238)U and (232)Th including their decay series isotopes in the agricultural soil of Mansa and Bathinda districts in the state of Punjab were presented and discussed. The measured mean radioactivity concentrations for (238)U, (232)Th and (40)K in the agricultural soil of the studied area differed from nationwide average crustal abundances by 51, 17 and 43 %, respectively. The sequence of the EFs of radionuclides in soil from the greatest to the least was found to be (238)U > (40)K > (226)Ra > (137)Cs > (232)Th > (228)Ra. Even though the enrichment of naturally occurring radionuclides was found to be higher, they remained to be in I(geo) class of '0', indicating that the soil is uncontaminated with respect to these radionuclides. Among non-metals, N showed the highest EF and belonged to I(geo) class of '2', indicating that soil is moderately contaminated due to intrusion of fertiliser. The resulting data set of elemental contents in soil was also interpreted by PCA, which facilitates identification of the different groups of correlated elements. The levels of the (40)K, (238)U and (232)Th radionuclides showed a significant positive correlation with each other, suggesting a similar origin of their geochemical sources and identical behaviour during transport in the soil system.

  14. Methane and nitrous oxide emissions of China: Sources from agricultural systems and mitigation options

    SciTech Connect

    Lin Erda; Li Yue; Dong Hongmin; Zhou Wennong

    1994-12-31

    This paper reports the estimated results of methane and nitrous oxide emissions from China`s agricultural systems. The results show that the overall methane emissions from paddies and ruminants were 11.335 and 5.796 Tg/y, respectively in 1990. For mitigation options, based on some experiments, a number of options were recommended to reduce methane and nitrous oxide emissions. Several research priority areas were proposed to reduce the uncertainties in estimates they are: (1) improve measurement methods; (2) further identify controlling factors; and (3) develop simulation models.

  15. Reducing future non-point source sediment and phosphorus loading under intensifying agricultural production in the Ethiopian highlands

    NASA Astrophysics Data System (ADS)

    Mogus, Mamaru; Schmitter, Petra; Tilahun, Seifu; Steenhuise, Tammo

    2016-04-01

    Intensification of agriculture will bring along non-point source pollution in the Ethiopian highlands resulting in eutrophication of lakes. The first signs of eutrophication have been observed already in Lake Tana. The lake it supports the lives of millions in the surrounding through fishing, tourism, transportation and hydropower.Presently, information on non-point source pollution is lacking in the Ethiopian highlands. There are few studies carried out in the highlands on the extent and the source areas of pollution, and models are not available for predicting sediment and phosphorus loading other than those developed for temperate climates. The objective of this chapter is to review existing non-point source studies, report on our findings of sediment and phosphorus sources that are related the non-point source pollution of Lake Tana and to present a non-point source model for the Ethiopian highland based on the Parameter Efficient Semi-distributed Watershed Hydrology Model (PED-WHM).In our research we have found that the saturation excess runoff from valley bottoms and from degraded lands are prevalent in the Ethiopia highlands. The periodically runoff source areas are also the sources for the non-point source pollution and by concentrating best management practices in these source areas we expect that we can reduce pollution without affecting the profitability of the existing farms. The water balance component of the non-point source model has been performing well in predicting both the discharge and the location of the runoff source areas. Sediment and phosphorus prediction models have been developed and are currently being tested for the 7km2Awramba watershed and the 1350 km2Gumara basin. Initial results indicate that 11.2 ton/ha/year sediment load and an accumulation rate of 17.3 mg/kg/year of dissolved phosphorus from Gumara watershed joining the lake. By developing best management practices at this time before non-point source pollution is rampant and

  16. Long-term agricultural non-point source pollution loading dynamics and correlation with outlet sediment geochemistry

    NASA Astrophysics Data System (ADS)

    Ouyang, Wei; Jiao, Wei; Li, Xiaoming; Giubilato, Elisa; Critto, Andrea

    2016-09-01

    Some agricultural non-point source (NPS) pollutants accumulate in sediments in the outlet sections of watersheds. It is crucial to evaluate the historical interactions between sediment properties and watershed NPS loading. Therefore, a sediment core from the outlet of an agricultural watershed was collected. The core age was dated using the 210Pb method, and sedimentation rates were determined using the constant rate of supply (CRS) model. The total nitrogen (TN), total phosphorus (TP), Cd, Pb, Cu, Ni and Cr accumulations in the sediment generally showed fluctuating increases, with the highest sedimentation fluxes all occurring in approximately 1998. The measurement of specific mass sedimentation rates reflected a record of watershed soil erosion dynamics. Using SWAT (Soil and Water Assessment Tool) to simulate long-term watershed agricultural NPS pollution loadings, the historical interactions between sediment properties and NPS loadings were further evaluated. The N leaching process weakened these interactions, but the historical accumulations of TP and heavy metals in sediments generally correlated well with watershed NPS TP loading. The regression analysis suggested that Pb and Cr were the most suitable indexes for assessing long-term NPS TN and TP pollution, respectively. Assessing the NPS loading dynamics using the vertical characteristics of sediment geochemistry is a new method.

  17. Fingerprinting Sources of Suspended Sediment in a Canadian Agricultural Watershed Using the MixSIAR Bayesian Unmixing Model

    NASA Astrophysics Data System (ADS)

    Smith, J. P.; Owens, P. N.; Gaspar, L.; Lobb, D. A.; Petticrew, E. L.

    2015-12-01

    An understanding of sediment redistribution processes and the main sediment sources within a watershed is needed to support watershed management strategies. The fingerprinting technique is increasingly being recognized as a method for establishing the source of the sediment transported within watersheds. However, the different behaviour of the various fingerprinting properties has been recognized as a major limitation of the technique, and the uncertainty associated with tracer selection needs to be addressed. There are also questions associated with which modelling approach (frequentist or Bayesian) is the best to unmix complex environmental mixtures, such as river sediment. This study aims to compare and evaluate the differences between fingerprinting predictions provided by a Bayesian unmixing model (MixSIAR) using different groups of tracer properties for use in sediment source identification. We used fallout radionuclides (e.g. 137Cs) and geochemical elements (e.g. As) as conventional fingerprinting properties, and colour parameters as emerging properties; both alone and in combination. These fingerprinting properties are being used (i.e. Koiter et al., 2013; Barthod et al., 2015) to determine the proportional contributions of fine sediment in the South Tobacco Creek Watershed, an agricultural watershed located in Manitoba, Canada. We show that the unmixing model using a combination of fallout radionuclides and geochemical tracers gave similar results to the model based on colour parameters. Furthermore, we show that a model that combines all tracers (i.e. radionuclide/geochemical and colour) gave similar results, showing that sediment sources change from predominantly topsoil in the upper reaches of the watershed to channel bank and bedrock outcrop material in the lower reaches. Barthod LRM et al. (2015). Selecting color-based tracers and classifying sediment sources in the assessment of sediment dynamics using sediment source fingerprinting. J Environ Qual

  18. Seasonal Variation in Hydrology Driving Shifts in Sources of Nitrate in an Agricultural Dominant Semi-arid Watershed

    NASA Astrophysics Data System (ADS)

    Moon Nielsen, L. G.; Orr, C. H.

    2010-12-01

    In the South Fork Palouse River in the semi-arid region of Eastern Washington State, surface water hydrology is driven by seasonal variation in precipitation, with peak surface water flow and highest Nitrate values observed from January to April, and lowest surface flows and corresponding lower Nitrate concentrations observed from June to August. Land-use in the watershed is predominantly non-irrigated cropland (82%) fertilized by synthetic fertilizer, with an additional 8% of land in urban areas. Due to the prevalence of anthropogenically influenced land in the watershed, Nitrate concentrations measured in streams here are chronically elevated above natural levels. Typically in an area that is dominated by agriculture, the source of Nitrate in surface waters draining agricultural land would be predicted to be synthetic fertilizer. However it is important to consider the impacts seasonal hydrological conditions can have upon Nitrate sources and flow paths. We investigated how Nitrate sources in Palouse streams and rivers changed seasonally to address the hypothesis that seasonal variation in precipitation shifts the dominant sources of Nitrate in surface waters. We based our determination of nitrogen source on the results from dual stable isotope analysis of Nitrate using the denitrifier method. Sampling was done at 7 locations of increasing catchment area along the South Fork Palouse River and tributary streams. Sampling site catchment area varied one order of magnitude from 70.9 to 717.4 km2. Surface waters at yearly low flow during the summer season indicated δ15N-Nitrate and δ18O-Nitrate ranging within generally accepted values to indicate Nitrate derived from animal and human waste. These can be attributed to waste water discharge from the urban areas in the watershed. Yearly hydrologic data suggests that during the winter season, increased precipitation causes a shift in δ15N-Nitrate and δ18O-Nitrate to values typically observed in sources derived from

  19. Sources of heavy metal pollution in agricultural soils of a rapidly industrializing area in the Yangtze Delta of China.

    PubMed

    Xu, Xianghua; Zhao, Yongcun; Zhao, Xiaoyan; Wang, Yudong; Deng, Wenjing

    2014-10-01

    The rapid industrialization and urbanization in developing countries have increased pollution by heavy metals, which is a concern for human health and the environment. In this study, 230 surface soil samples (0-20cm) were collected from agricultural areas of Jiaxing, a rapidly industrializing area in the Yangtze Delta of China. Sequential Gaussian simulation (SGS) and multivariate factorial kriging analysis (FKA) were used to identify and explore the sources of heavy metal pollution for eight metals (Cu, Zn, Pb, Cr, Ni, Cd, Hg and As). Localized hot-spots of pollution were identified for Cu, Zn, Pb, Cr, Ni and Cd with area percentages of 0.48 percent, 0.58 percent, 2.84 percent, 2.41 percent, 0.74 percent, and 0.68 percent, respectively. The areas with Hg pollution covered approximately 38 percent whereas no potential pollution risk was found for As. The soil parent material and point sources of pollution had significant influences on Cr, Ni, Cu, Zn and Cd levels, except for the influence of agricultural management practices also accounted for micro-scale variations (nugget effect) for Cu and Zn pollution. Short-range (4km) diffusion processes had a significant influence on Cu levels, although they did not appear to be the dominant sources of Zn and Cd variation. The short-range diffusion pollution arising from current and historic industrial emissions and urbanization, and long-range (33km) variations in soil parent materials and/or diffusion jointly determined the current concentrations of soil Pb. The sources of Hg pollution risk may be attributed to the atmosphere deposition of industrial emission and historical use of Hg-containing pesticides.

  20. Agricultural Wastes.

    ERIC Educational Resources Information Center

    Jewell, W. J.; Switzenbaum, M. S.

    1978-01-01

    Presents a literature review of agricultural wastes, covering publications of 1976-77. Some of the areas covered are: (1) water characteristics and impacts; (2) waste treatment; (3) reuse of agricultural wastes; and (4) nonpoint pollution sources. A list of 150 references is also presented. (HM)

  1. Using Radioactive Fallout Cesium (137Cs) to Distinguish Sediment Sources in an Agricultural Watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Radioactive fallout Cesium (Cs-137) has been used for quantifying sources of accumulating sediment in water bodies and to determine the rates and pattern of soil erosion. The objectives of this research are to use Cs-137 as a tracer to determine patterns of soil erosion and deposition of eroding soi...

  2. Organic matter source and degradation as revealed by molecular biomarkers in agricultural soils of Yuanyang terrace

    PubMed Central

    Li, Fangfang; Pan, Bo; Zhang, Di; Yang, Xiaolei; Li, Hao; Liao, Shaohua; Ghaffar, Abdul; Peng, Hongbo; Xing, Baoshan

    2015-01-01

    Three soils with different tillage activities were collected and compared for their organic matter sources and degradation. Two soils (TD and TP) with human activities showed more diverse of chemicals in both free lipids and CuO oxidation products than the one (NS) without human activities. Branched alkanoic acids only accounted for less than 5% of lipids, indicating limited microbial inputs in all three investigated soils. The degradation of lignin in NS and TD was relatively higher than TP, probably because of the chemical degradation, most likely UV light-involved photodegradation. Lignin parameters obtained from CuO oxidation products confirmed that woody gymnosperm tissue (such as pine trees) may be the main source for NS, while angiosperm tissues from vascular plant may be the predominant source for the lignins in TD and TP. Analysis of BPCAs illustrated that BC in NS may be mainly originated from soot or other fossil carbon sources, whereas BC in TD and TP may be produced during corn stalk and straw burning. BC was involved in mineral interactions for TD and TP. The dynamics of organic matter needs to be extensively examined for their nonideal interactions with contaminants. PMID:26046574

  3. Organic matter source and degradation as revealed by molecular biomarkers in agricultural soils of Yuanyang terrace

    NASA Astrophysics Data System (ADS)

    Li, Fangfang; Pan, Bo; Zhang, Di; Yang, Xiaolei; Li, Hao; Liao, Shaohua; Ghaffar, Abdul; Peng, Hongbo; Xing, Baoshan

    2015-06-01

    Three soils with different tillage activities were collected and compared for their organic matter sources and degradation. Two soils (TD and TP) with human activities showed more diverse of chemicals in both free lipids and CuO oxidation products than the one (NS) without human activities. Branched alkanoic acids only accounted for less than 5% of lipids, indicating limited microbial inputs in all three investigated soils. The degradation of lignin in NS and TD was relatively higher than TP, probably because of the chemical degradation, most likely UV light-involved photodegradation. Lignin parameters obtained from CuO oxidation products confirmed that woody gymnosperm tissue (such as pine trees) may be the main source for NS, while angiosperm tissues from vascular plant may be the predominant source for the lignins in TD and TP. Analysis of BPCAs illustrated that BC in NS may be mainly originated from soot or other fossil carbon sources, whereas BC in TD and TP may be produced during corn stalk and straw burning. BC was involved in mineral interactions for TD and TP. The dynamics of organic matter needs to be extensively examined for their nonideal interactions with contaminants.

  4. The role of hydrology in connecting agricultural phosphorus sources to surface water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Minimizing the risk of phosphorus (P) loss from land to water represents one of the most important priorities of nutrient management in the Chesapeake Bay watershed. Simply put, for P to pose a water quality problem, there must be a source of P that can readily be connected to surface water by hydro...

  5. Stream nitrogen sources apportionment and pollution control scheme development in an agricultural watershed in eastern China.

    PubMed

    Chen, Dingjiang; Lu, Jun; Huang, Hong; Liu, Mei; Gong, Dongqin; Chen, Jiabo

    2013-08-01

    A modeling system that couples a land-usebased export coefficient model, a stream nutrient transport equation, and Bayesian statistics was developed for stream nitrogen source apportionment. It divides a watershed into several sub-catchments, and then considers the major landuse categories as stream nitrogen sources in each subcatchment. The runoff depth and stream water depth are considered as the major factors influencing delivery of nitrogen from land to downstream stream node within each sub-catchment. The nitrogen sources and delivery processes are lumped into several constant parameters that were calibrated using Bayesian statistics from commonly available stream monitoring and land-use datasets. This modeling system was successfully applied to total nitrogen (TN) pollution control scheme development for the ChangLe River watershed containing six sub-catchments and four land-use categories. The temporal (across months and years) and spatial (across sub-catchments and land-use categories) variability of nonpoint source (NPS) TN export to stream channels and delivery to the watershed outlet were assessed. After adjustment for in-stream TNretention, the time periods and watershed areas with disproportionately high-TN contributions to the stream were identified. Aimed at a target stream TN level of 2 mg L-1, a quantitative TN pollution control scheme was further developed to determine which sub-catchments, which land-use categories in a sub-catchment, which time periods, and how large of NPS TN export reduction were required. This modeling system provides a powerful tool for stream nitrogen source apportionment and pollution control scheme development at the watershed scale and has only limited data requirements.

  6. Agricultural waste as a source for the production of silica nanoparticles

    NASA Astrophysics Data System (ADS)

    Vaibhav, Vineet; Vijayalakshmi, U.; Roopan, S. Mohana

    2015-03-01

    The major interest of the paper deals with the extraction of silica from four natural sources such as rice husk, bamboo leaves, sugarcane bagasse and groundnut shell. These waste materials in large quantities can create a serious environmental problem. Hence, there is a need to adopt proper strategy to reduce the waste. In the present investigation, all the waste materials are subjected to moisture removal in a hot plate and sintered at 900 °C for 7 h. The sintered powder was treated with 1 M NaOH to form sodium silicate and then with 6 M H2SO4 to precipitate silica. The prepared silica powders were characterized by FT-IR, XRD and SEM-EDAX analysis. The silica recovered from different sources was found to vary between 52% and 78%. Magnesium substituted silica was formed from the groundnut waste and further treatment is required to precipitate silica.

  7. [Mechanism of stomatal regulation by root sourced signaling and its agricultural signficance].

    PubMed

    Guo, Anhong; Li, Zhaoxiang; Liu, Gengshan; Yang, Yuanyan; An, Shunqing

    2004-06-01

    Under soil drought condition, root sourced signal abcisic acid (ABA) plays an important role in the long distance signaling process, and can be a measurement of soil water availability. ABA is also an effective stomatal closing agent, and acts to reduce transpiration and canopy water loss. This paper briefly introduced the physiological mechanism and theoretical model about the stomatal regulation by root sourced signaling, and indicated that the combination of this model with root water absorption model and stomatal conductance model could be more effective in depicting the response of plant to soil drying and atmospheric drought. In addition, some effective irrigation approaches, such as regulated deficit irrigation (RDI), partial root-zone drying (PRD) and controlled alternative irrigation (CAI) were profited from the mechanism of plant water use regulation by the root sourced signaling. These irrigation measures favored to reasonably distribute available soil water in root-zone. Root signaling system also played important role in regulating root growth and its development, retarding shoot growth to adjusting root shoot ratio, and optimizing assimilation allocation to favor to improve reproductive development. These processes hold substantial promise for enhancing crop water use efficiency. PMID:15362642

  8. U.S.-State Agricultural Data. Agriculture Information Bulletin Number 512.

    ERIC Educational Resources Information Center

    Womack, Letricia M.; Traub, Larry G.

    This report presents agricultural information for each state and the United States as a whole for the years 1981-1985. Included are data on population, land use, agricultural production, farm income, value of assets on farms, and selected characteristics of farms. The primary data sources are the "1982 Census of Agriculture," the "Economic…

  9. Targeting allergenic fungi in agricultural environments aids the identification of major sources and potential risks for human health.

    PubMed

    Weikl, F; Radl, V; Munch, J C; Pritsch, K

    2015-10-01

    Fungi are, after pollen, the second most important producers of outdoor airborne allergens. To identify sources of airborne fungal allergens, a workflow for qPCR quantification from environmental samples was developed, thoroughly tested, and finally applied. We concentrated on determining the levels of allergenic fungi belonging to Alternaria, Cladosporium, Fusarium, and Trichoderma in plant and soil samples from agricultural fields in which cereals were grown. Our aims were to identify the major sources of allergenic fungi and factors potentially influencing their occurrence. Plant materials were the main source of the tested fungi at and after harvest. Amounts of A. alternata and C. cladosporioides varied significantly in fields under different management conditions, but absolute levels were very high in all cases. This finding suggests that high numbers of allergenic fungi may be an inevitable side effect of farming in several crops. Applied in large-scale studies, the concept described here may help to explain the high number of sensitization to airborne fungal allergens.

  10. Tracing sources of suspended sediment in a Canadian agricultural watershed using a Bayesian model: Testing different groups of fingerprinting properties

    NASA Astrophysics Data System (ADS)

    Gaspar, Leticia; Owens, Philip; Petticrew, Ellen; Lobb, David; Koiter, Alexander; Reiffarth, Dominic; Barthod, Louise; Liu, Kui; Martinez-Carreras, Nuria

    2015-04-01

    An understanding of sediment redistribution processes and the main sediment sources within a watershed is needed to support catchment management strategies, to control soil erosion processes, and to preserve water quality and ecological status. The fingerprinting technique is increasingly recognised as a method for establishing the source of the sediment transported within a catchment. However, the different behaviour of the various fingerprinting properties has been recognised as a major limitation of the technique, and the uncertainty associated with tracer selection has to be addressed. Do the different properties give similar results? Can we combine different groups of tracers? This study aims to compare and evaluate the differences between fingerprinting predictions provided by a Bayesian mixing model using different groups of tracer properties for use in sediment source identification. We are employing fallout radionuclides (137Cs, 210Pbex) and geochemical elements as conventional fingerprinting properties, and colour parameters and compound-specific stable isotopes (CSSIs) as emerging properties; both alone and in combination. These fingerprinting properties are being used to determine the proportional contributions of fine sediment in the South Tobacco Creek Watershed, an agricultural catchment located in south-central Manitoba in Canada. We present preliminary results to evaluate the use of different statistical procedures to increase the accuracy of fingerprinting outputs and establish protocols for the selection of appropriate fingerprint properties.

  11. Targeting allergenic fungi in agricultural environments aids the identification of major sources and potential risks for human health.

    PubMed

    Weikl, F; Radl, V; Munch, J C; Pritsch, K

    2015-10-01

    Fungi are, after pollen, the second most important producers of outdoor airborne allergens. To identify sources of airborne fungal allergens, a workflow for qPCR quantification from environmental samples was developed, thoroughly tested, and finally applied. We concentrated on determining the levels of allergenic fungi belonging to Alternaria, Cladosporium, Fusarium, and Trichoderma in plant and soil samples from agricultural fields in which cereals were grown. Our aims were to identify the major sources of allergenic fungi and factors potentially influencing their occurrence. Plant materials were the main source of the tested fungi at and after harvest. Amounts of A. alternata and C. cladosporioides varied significantly in fields under different management conditions, but absolute levels were very high in all cases. This finding suggests that high numbers of allergenic fungi may be an inevitable side effect of farming in several crops. Applied in large-scale studies, the concept described here may help to explain the high number of sensitization to airborne fungal allergens. PMID:26022406

  12. 78 FR 49506 - Source Power & Gas LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-14

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Source Power & Gas LLC; Supplemental Notice That Initial Market- Based Rate...-referenced proceeding of Source Power & Gas LLC's application for market-based rate authority, with...

  13. Assessment of groundwater vulnerability to nitrates from agricultural sources using a GIS-compatible logic multicriteria model.

    PubMed

    Rebolledo, Boris; Gil, Antonia; Flotats, Xavier; Sánchez, José Ángel

    2016-04-15

    In the present study an overlay method to assess groundwater vulnerability is proposed. This new method based on multicriteria decision analysis (MCDA) was developed and validated using an appropriate case study in Aragon area (NE Spain). The Vulnerability Index to Nitrates from Agricultural Sources (VINAS) incorporates a novel Logic Scoring of Preferences (LSP) approach, and it has been developed using public geographic information from the European Union. VINAS-LSP identifies areas with five categories of vulnerability, taking into account the hydrogeological and environmental characteristics of the territory as a whole. The resulting LSP map is a regional screening tool that can provide guidance on the potential risk of nitrate pollution, as well as highlight areas where specific research and farming planning policies are required. PMID:26874616

  14. Assessment of groundwater vulnerability to nitrates from agricultural sources using a GIS-compatible logic multicriteria model.

    PubMed

    Rebolledo, Boris; Gil, Antonia; Flotats, Xavier; Sánchez, José Ángel

    2016-04-15

    In the present study an overlay method to assess groundwater vulnerability is proposed. This new method based on multicriteria decision analysis (MCDA) was developed and validated using an appropriate case study in Aragon area (NE Spain). The Vulnerability Index to Nitrates from Agricultural Sources (VINAS) incorporates a novel Logic Scoring of Preferences (LSP) approach, and it has been developed using public geographic information from the European Union. VINAS-LSP identifies areas with five categories of vulnerability, taking into account the hydrogeological and environmental characteristics of the territory as a whole. The resulting LSP map is a regional screening tool that can provide guidance on the potential risk of nitrate pollution, as well as highlight areas where specific research and farming planning policies are required.

  15. Quantifying the Earthquake Clustering that Independent Sources with Stationary Rates (as Included in Current Risk Models) Can Produce.

    NASA Astrophysics Data System (ADS)

    Fitzenz, D. D.; Nyst, M.; Apel, E. V.; Muir-Wood, R.

    2014-12-01

    The recent Canterbury earthquake sequence (CES) renewed public and academic awareness concerning the clustered nature of seismicity. Multiple event occurrence in short time and space intervals is reminiscent of aftershock sequences, but aftershock is a statistical definition, not a label one can give an earthquake in real-time. Aftershocks are defined collectively as what creates the Omori event rate decay after a large event or are defined as what is taken away as "dependent events" using a declustering method. It is noteworthy that depending on the declustering method used on the Canterbury earthquake sequence, the number of independent events varies a lot. This lack of unambiguous definition of aftershocks leads to the need to investigate the amount of clustering inherent in "declustered" risk models. This is the task we concentrate on in this contribution. We start from a background source model for the Canterbury region, in which 1) centroids of events of given magnitude are distributed using a latin-hypercube lattice, 2) following the range of preferential orientations determined from stress maps and focal mechanism, 3) with length determined using the local scaling relationship and 4) rates from a and b values derived from the declustered pre-2010 catalog. We then proceed to create tens of thousands of realizations of 6 to 20 year periods, and we define criteria to identify which successions of events in the region would be perceived as a sequence. Note that the spatial clustering expected is a lower end compared to a fully uniform distribution of events. Then we perform the same exercise with rates and b-values determined from the catalog including the CES. If the pre-2010 catalog was long (or rich) enough, then the computed "stationary" rates calculated from it would include the CES declustered events (by construction, regardless of the physical meaning of or relationship between those events). In regions of low seismicity rate (e.g., Canterbury before

  16. 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

  17. 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.

  18. Nitrate sinks and sources as controls of spatio-temporal water quality dynamics in an agricultural headwater catchment

    NASA Astrophysics Data System (ADS)

    Schuetz, Tobias; Gascuel-Odoux, Chantal; Durand, Patrick; Weiler, Markus

    2016-02-01

    Several controls are known to affect water quality of stream networks during flow recession periods, such as solute leaching processes, surface water-groundwater interactions as well as biogeochemical in-stream turnover processes. Throughout the stream network, combinations of specific water and solute export rates and local in-stream conditions overlay the biogeochemical signals from upstream sections. Therefore, upstream sections can be considered functional units which could be distinguished and ordered regarding their relative contribution to nutrient dynamics at the catchment outlet. Based on snapshot sampling of flow and nitrate concentrations along the stream in an agricultural headwater during the summer flow recession period, we determined spatial and temporal patterns of water quality for the whole stream. A data-driven, in-stream-mixing-and-removal model was developed and applied for analysing the spatio-temporal in-stream retention processes and their effect on the spatio-temporal fluxes of nitrate from subcatchments. Thereby, we have been able to distinguish quantitatively between nitrate sinks, sources per stream reaches, and subcatchments, and thus we could disentangle the overlay of nitrate sink and source signals. For nitrate sources, we determined their permanent and temporal impact on stream water quality and for nitrate sinks, we found increasing nitrate removal efficiencies from upstream to downstream. Our results highlight the importance of distinct nitrate source locations within the watershed for in-stream concentrations and in-stream removal processes, respectively. Thus, our findings contribute to the development of a more dynamic perception of water quality in streams and rivers concerning ecological and sustainable water resource management.

  19. Phosphorus Recycling from an Unexplored Source by Polyphosphate Accumulating Microalgae and Cyanobacteria-A Step to Phosphorus Security in Agriculture.

    PubMed

    Mukherjee, Chandan; Chowdhury, Rajojit; Ray, Krishna

    2015-01-01

    Phosphorus (P), an essential element required for crop growth has no substitute. The global food security depends on phosphorus availability in soil for crop production. World phosphorus reserves are fast depleting and with an annual increase of 2.3% in phosphorus demand, the current reserves will be exhausted in coming 50-100 years. India and other Western countries are forced to import phosphorus fertilizers at high costs to meet their agricultural demands due to uneven distribution of phosphate rocks on earth. The present study from India, aims to draw attention to an unnoticed source of phosphorus being wasted as parboiled rice mill effluent and subsequent bio-recovery of the valuable element from this unconventional source. The research was conducted in West Bengal, India, a state with the highest number of parboiled rice mills where its effluent carries on an average ~40 mg/L of soluble phosphorus. Technology to recover and recycle this wastewater P in India in a simple, inexpensive mode is yet to be optimized. Our strategy to use microalgae, Chlorella sp. and cyanobacteria, Cyanobacterium sp., Lyngbya sp., and Anabaena sp. to sequester the excess phosphorus from the effluent as polyphosphate inclusions and its subsequent recycling as slow and moderate release phosphorus biofertilizers to aid plant growth, preventing phosphorus loss and pollution, is a contemporary venture to meet the need of the hour. These polyphosphate accumulating microorganisms play a dual role of remediation and recovery of phosphorus, preliminarily validated in laboratory scale. PMID:26733966

  20. Dioxins, furans, biphenyls, arsenic, thorium and uranium in natural and anthropogenic sources of phosphorus and calcium used in agriculture.

    PubMed

    Avelar, A C; Ferreira, W M; Pemberthy, D; Abad, E; Amaral, M A

    2016-05-01

    The aim of this study was to assess the presence of dioxins, furans and biphenyls, and the inorganic contaminants such as arsenic (As), thorium (Th) and uranium (U) in three main products used in Agriculture in Brazil: feed grade dicalcium phosphate, calcined bovine bone meal and calcitic limestone. The first two are anthropogenic sources of phosphorus and calcium, while calcitic limestone is a natural unprocessed mineral. Regarding to dioxin-like substances, all samples analyzed exhibited dioxins (PCDD) and furans (PCDF) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations below limit of detection (LOD). In general, achieved is in accordance with regulation in Brazil where is established a maximum limit in limestone used in the citric pulp production (0.50pg WHO-TEQ g(-1)). In addition, reported data revealed very low levels for limestone in comparison with similar materials reported by European legislation. As result for toxic metals, achieved data were obtained using Instrumental Neutron Activation Analysis (INAA). On one hand, limestone sample exhibits the largest arsenic concentration. On another hand, dicalcium phosphate exhibited the largest uranium concentration, which represents a standard in animal nutrition. Therefore, it is phosphorus source in the animal feed industry can be a goal of concern in the feed field. PMID:26901743

  1. Dioxins, furans, biphenyls, arsenic, thorium and uranium in natural and anthropogenic sources of phosphorus and calcium used in agriculture.

    PubMed

    Avelar, A C; Ferreira, W M; Pemberthy, D; Abad, E; Amaral, M A

    2016-05-01

    The aim of this study was to assess the presence of dioxins, furans and biphenyls, and the inorganic contaminants such as arsenic (As), thorium (Th) and uranium (U) in three main products used in Agriculture in Brazil: feed grade dicalcium phosphate, calcined bovine bone meal and calcitic limestone. The first two are anthropogenic sources of phosphorus and calcium, while calcitic limestone is a natural unprocessed mineral. Regarding to dioxin-like substances, all samples analyzed exhibited dioxins (PCDD) and furans (PCDF) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations below limit of detection (LOD). In general, achieved is in accordance with regulation in Brazil where is established a maximum limit in limestone used in the citric pulp production (0.50pg WHO-TEQ g(-1)). In addition, reported data revealed very low levels for limestone in comparison with similar materials reported by European legislation. As result for toxic metals, achieved data were obtained using Instrumental Neutron Activation Analysis (INAA). On one hand, limestone sample exhibits the largest arsenic concentration. On another hand, dicalcium phosphate exhibited the largest uranium concentration, which represents a standard in animal nutrition. Therefore, it is phosphorus source in the animal feed industry can be a goal of concern in the feed field.

  2. Phosphorus Recycling from an Unexplored Source by Polyphosphate Accumulating Microalgae and Cyanobacteria—A Step to Phosphorus Security in Agriculture

    PubMed Central

    Mukherjee, Chandan; Chowdhury, Rajojit; Ray, Krishna

    2015-01-01

    Phosphorus (P), an essential element required for crop growth has no substitute. The global food security depends on phosphorus availability in soil for crop production. World phosphorus reserves are fast depleting and with an annual increase of 2.3% in phosphorus demand, the current reserves will be exhausted in coming 50–100 years. India and other Western countries are forced to import phosphorus fertilizers at high costs to meet their agricultural demands due to uneven distribution of phosphate rocks on earth. The present study from India, aims to draw attention to an unnoticed source of phosphorus being wasted as parboiled rice mill effluent and subsequent bio-recovery of the valuable element from this unconventional source. The research was conducted in West Bengal, India, a state with the highest number of parboiled rice mills where its effluent carries on an average ~40 mg/L of soluble phosphorus. Technology to recover and recycle this wastewater P in India in a simple, inexpensive mode is yet to be optimized. Our strategy to use microalgae, Chlorella sp. and cyanobacteria, Cyanobacterium sp., Lyngbya sp., and Anabaena sp. to sequester the excess phosphorus from the effluent as polyphosphate inclusions and its subsequent recycling as slow and moderate release phosphorus biofertilizers to aid plant growth, preventing phosphorus loss and pollution, is a contemporary venture to meet the need of the hour. These polyphosphate accumulating microorganisms play a dual role of remediation and recovery of phosphorus, preliminarily validated in laboratory scale. PMID:26733966

  3. A lighting assembly based on red and blue light-emitting diodes as a lighting source for space agriculture

    NASA Astrophysics Data System (ADS)

    Avercheva, Olga; Berkovich, Yuliy A.; Smolyanina, Svetlana; Bassarskaya, Elizaveta; Zhigalova, Tatiana; Ptushenko, Vasiliy; Erokhin, Alexei

    Light-emitting diodes (LEDs) are a promising lighting source for space agriculture due to their high efficiency, longevity, safety, and other factors. Assemblies based on red and blue LEDs have been recommended in literature, although not all plants show sufficient productivity in such lighting conditions. Adding of green LEDs proposed in some works was aimed at psychological support for the crew, and not at the improvement of plant growth. We studied the growth and the state of the photosynthetic apparatus in Chinese cabbage (Brassica chinensis L.) plants grown under red (650 nm) and blue (470 nm) light-emitting diodes (LEDs). Plants grown under a high-pressure sodium lamp (HPS lamp) were used as a control. The plants were illuminated with two photosynthetic photon flux levels: nearly 400 µE and about 100 µE. Plants grown under LEDs with 400 µE level, as compared to control plants, showed lower fresh weight, edible biomass, growth rate, and sugar content. The difference in fresh weight and edible biomass was even more pronounced in plants grown with 100 µE level; the data indicate that the adaptability of the test plants to insufficient lighting decreased. Under LEDs, we observed the decreasing of root growth and the absence of transition to the flowering stage, which points to a change in the hormonal balance in plants grown in such lighting conditions. We also found differences in the functioning of the photosynthetic apparatus and its reaction to a low lighting level. We have concluded that a lighting assembly with red and blue LEDs only is insufficient for the plant growth and productivity, and can bring about alterations in their adaptive and regulatory mechanisms. Further studies are needed to optimize the lighting spectrum for space agriculture, taking into account the photosynthetic, phototropic and regulatory roles of light. Using white LEDs or adding far-red and green LEDs might be a promising approach.

  4. Application of strontium isotope measurements to trace sediment sources in an upstream agricultural catchment (Loire River basin, France)

    NASA Astrophysics Data System (ADS)

    Le Gall, Marion; Evrard, Olivier; Thil, François; Foucher, Anthony; Salvador-Blanes, Sébastien; Cerdan, Olivier; Ayrault, Sophie

    2015-04-01

    Soil erosion is recognized as one of the main processes of land degradation in agricultural areas. It accelerates the supply of sediment to the rivers and degrades water quality. To limit those impacts and optimize management programs in such areas, sources of sediment need to be identified and sediment transport to be controlled. Here, we determined the sources of suspended sediment in the Louroux (24 km², French Loire River basin), a small catchment representative of lowland cultivated environments of Northwestern Europe. In this catchment, channels have been reshaped and 220 tile drain outlets have been installed over the last several decades. As a result, soil erosion and sediment fluxes have increased drastically. The variation of 87Sr/86Sr ratios, driven by the weathering of rocks with different ages and chemical composition, may reflect the mixing of different sediment sources. Strontium isotopic ratios (87Sr/86Sr) were therefore determined in potential soil sources, suspended particulate matter (SPM) and a sediment core sampled in the Louroux Pond at the catchment outlet. Soil, SPM and core samples displayed significantly different isotopic signatures. 87Sr/86Sr ratios in soil samples varied from 0.712763 to 0.724631 ± 0.000017 (2σ, n=20). Highest values were observed in silicic parts of the catchment whereas the lower values were identified in a calcareous area close to the Louroux Pond. 87Sr/86Sr ratios in SPM (0.713660 to 0.725749 ± 0.000017, 2σ, n=20) plotted between the soil and sediment core (0.712255 to 0.716415 ± 0.000017, 2σ, n=12), suggesting the presence of particles originating from at least two different lithological sources, i.e. silicic rocks and carbonate material. Variations in 87Sr/86Sr ratios in the outlet core sample were used to reconstruct the sedimentary dynamics in the catchment during the last decades. These results will guide the future implementation of appropriate management practices aiming to reduce erosion in upstream

  5. 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

  6. Interactions between Bifidobacterium and Bacteroides Species in Cofermentations Are Affected by Carbon Sources, Including Exopolysaccharides Produced by Bifidobacteria

    PubMed Central

    Rios-Covian, David; Arboleya, Silvia; Hernandez-Barranco, Ana M.; Alvarez-Buylla, Jorge R.; Ruas-Madiedo, Patricia; Gueimonde, Miguel

    2013-01-01

    Cocultures of strains from two Bifidobacterium and two Bacteroides species were performed with exopolysaccharides (EPS) previously purified from bifidobacteria, with inulin, or with glucose as the carbon source. Bifidobacterium longum NB667 and Bifidobacterium breve IPLA20004 grew in glucose but showed poor or no growth in complex carbohydrates (inulin, EPS E44, and EPS R1), whereas Bacteroides grew well in the four carbon sources tested. In the presence of glucose, the growth of Bacteroides thetaiotaomicron DSM-2079 was inhibited by B. breve, whereas it remained unaffected in the presence of B. longum. Ba. fragilis DSM-2151 contributed to a greater survival of B. longum, promoting changes in the synthesis of short-chain fatty acids (SCFA) and organic acids in coculture with respect to monocultures. In complex carbohydrates, cocultures of bifidobacterium strains with Ba. thetaiotaomicron did not modify the behavior of Bacteroides nor improve the poor growth of bifidobacteria. The metabolic activity of Ba. fragilis in coculture with bifidobacteria was not affected by EPS, but greater survival of bifidobacteria at late stages of incubation occurred in cocultures than in monocultures, leading to a higher production of acetic acid than in monocultures. Therefore, cocultures of Bifidobacterium and Bacteroides can behave differently against fermentable carbohydrates as a function of the specific characteristics of the strains from each species. These results stress the importance of considering specific species and strain interactions and not simply higher taxonomic divisions in the relationship among intestinal microbial populations and their different responses to probiotics and prebiotics. PMID:24077708

  7. Using SWAT, Bacteroidales microbial source tracking markers, and fecal indicator bacteria to predict waterborne pathogen occurrence in an agricultural watershed.

    PubMed

    Frey, Steven K; Topp, Edward; Edge, Thomas; Fall, Claudia; Gannon, Victor; Jokinen, Cassandra; Marti, Romain; Neumann, Norman; Ruecker, Norma; Wilkes, Graham; Lapen, David R

    2013-10-15

    Developing the capability to predict pathogens in surface water is important for reducing the risk that such organisms pose to human health. In this study, three primary data source scenarios (measured stream flow and water quality, modelled stream flow and water quality, and host-associated Bacteroidales) are investigated within a Classification and Regression Tree Analysis (CART) framework for classifying pathogen (Escherichia coli 0157:H7, Salmonella, Campylobacter, Cryptosporidium, and Giardia) presence and absence (P/A) for a 178 km(2) agricultural watershed. To provide modelled data, a Soil Water Assessment Tool (SWAT) model was developed to predict stream flow, total suspended solids (TSS), total N and total P, and fecal indicator bacteria loads; however, the model was only successful for flow and total N and total P simulations, and did not accurately simulate TSS and indicator bacteria transport. Also, the SWAT model was not sensitive to an observed reduction in the cattle population within the watershed that may have resulted in significant reduction in E. coli concentrations and Salmonella detections. Results show that when combined with air temperature and precipitation, SWAT modelled stream flow and total P concentrations were useful for classifying pathogen P/A using CART methodology. From a suite of host-associated Bacteroidales markers used as independent variables in CART analysis, the ruminant marker was found to be the best initial classifier of pathogen P/A. Of the measured sources of independent variables, air temperature, precipitation, stream flow, and total P were found to be the most important variables for classifying pathogen P/A. Results indicate a close relationship between cattle pollution and pathogen occurrence in this watershed, and an especially strong link between the cattle population and Salmonella detections. PMID:24079968

  8. Sustainable Sourcing of Global Agricultural Raw Materials: Assessing Gaps in Key Impact and Vulnerability Issues and Indicators

    PubMed Central

    Springer, Nathaniel P.; Garbach, Kelly; Guillozet, Kathleen; Haden, Van R.; Hedao, Prashant; Hollander, Allan D.; Huber, Patrick R.; Ingersoll, Christina; Langner, Megan; Lipari, Genevieve; Mohammadi, Yaser; Musker, Ruthie; Piatto, Marina; Riggle, Courtney; Schweisguth, Melissa; Sin, Emily; Snider, Sara; Vidic, Nataša; White, Aubrey; Brodt, Sonja; Quinn, James F.; Tomich, Thomas P.

    2015-01-01

    Understanding how to source agricultural raw materials sustainably is challenging in today’s globalized food system given the variety of issues to be considered and the multitude of suggested indicators for representing these issues. Furthermore, stakeholders in the global food system both impact these issues and are themselves vulnerable to these issues, an important duality that is often implied but not explicitly described. The attention given to these issues and conceptual frameworks varies greatly—depending largely on the stakeholder perspective—as does the set of indicators developed to measure them. To better structure these complex relationships and assess any gaps, we collate a comprehensive list of sustainability issues and a database of sustainability indicators to represent them. To assure a breadth of inclusion, the issues are pulled from the following three perspectives: major global sustainability assessments, sustainability communications from global food companies, and conceptual frameworks of sustainable livelihoods from academic publications. These terms are integrated across perspectives using a common vocabulary, classified by their relevance to impacts and vulnerabilities, and categorized into groups by economic, environmental, physical, human, social, and political characteristics. These issues are then associated with over 2,000 sustainability indicators gathered from existing sources. A gap analysis is then performed to determine if particular issues and issue groups are over or underrepresented. This process results in 44 “integrated” issues—24 impact issues and 36 vulnerability issues —that are composed of 318 “component” issues. The gap analysis shows that although every integrated issue is mentioned at least 40% of the time across perspectives, no issue is mentioned more than 70% of the time. A few issues infrequently mentioned across perspectives also have relatively few indicators available to fully represent them

  9. Sustainable Sourcing of Global Agricultural Raw Materials: Assessing Gaps in Key Impact and Vulnerability Issues and Indicators.

    PubMed

    Springer, Nathaniel P; Garbach, Kelly; Guillozet, Kathleen; Haden, Van R; Hedao, Prashant; Hollander, Allan D; Huber, Patrick R; Ingersoll, Christina; Langner, Megan; Lipari, Genevieve; Mohammadi, Yaser; Musker, Ruthie; Piatto, Marina; Riggle, Courtney; Schweisguth, Melissa; Sin, Emily; Snider, Sara; Vidic, Nataša; White, Aubrey; Brodt, Sonja; Quinn, James F; Tomich, Thomas P

    2015-01-01

    Understanding how to source agricultural raw materials sustainably is challenging in today's globalized food system given the variety of issues to be considered and the multitude of suggested indicators for representing these issues. Furthermore, stakeholders in the global food system both impact these issues and are themselves vulnerable to these issues, an important duality that is often implied but not explicitly described. The attention given to these issues and conceptual frameworks varies greatly--depending largely on the stakeholder perspective--as does the set of indicators developed to measure them. To better structure these complex relationships and assess any gaps, we collate a comprehensive list of sustainability issues and a database of sustainability indicators to represent them. To assure a breadth of inclusion, the issues are pulled from the following three perspectives: major global sustainability assessments, sustainability communications from global food companies, and conceptual frameworks of sustainable livelihoods from academic publications. These terms are integrated across perspectives using a common vocabulary, classified by their relevance to impacts and vulnerabilities, and categorized into groups by economic, environmental, physical, human, social, and political characteristics. These issues are then associated with over 2,000 sustainability indicators gathered from existing sources. A gap analysis is then performed to determine if particular issues and issue groups are over or underrepresented. This process results in 44 "integrated" issues--24 impact issues and 36 vulnerability issues--that are composed of 318 "component" issues. The gap analysis shows that although every integrated issue is mentioned at least 40% of the time across perspectives, no issue is mentioned more than 70% of the time. A few issues infrequently mentioned across perspectives also have relatively few indicators available to fully represent them. Issues in the

  10. Effect of hillslope position and manure application rates on the persistence of fecal source tracking indicators in an agricultural soil.

    PubMed

    Piorkowski, Gregory S; Bezanson, Greg S; Jamieson, Rob C; Hansen, Lisbeth Truelstrup; Yost, Chris K

    2014-03-01

    The influence of liquid dairy manure (LDM) application rates (12.5 and 25 kL ha) and soil type on the decay rates of library-independent fecal source tracking markers (host-associated and mitochondrial DNA) and persistent (>58 d) population structure was examined in a field study. The soils compared were an Aquic Haplorthod and a Typic Haplorthod in Nova Scotia, Canada, that differed according to landscape position and soil moisture regime. Soil type and LDM application rate did not influence decay rates (0.045-0.057 d). population structure, in terms of the occurrence of abundance of strain types, varied according to soil type ( = 0.012) but did not vary by LDM application rate ( = 0.121). Decay of ruminant-specific (BacR), bovine-specific (CowM2), and mitochondrial DNA (AcytB) markers was analyzed for 13 d after LDM application. The decay rates of BacR were greater under high-LDM application rates (0.281-0.358 d) versus low-LDM application rates (0.212-0.236 d) but were unaffected by soil type. No decay rates could be calculated for the CowM2 marker because it was undetectable within 6 d after manure application. Decay rates for AcytB were lower for the Aquic Haplorthod (0.088-0.100 d), with higher moisture status compared with the Typic Haplorthod (0.135 d). Further investigation into the decay of fecal source tracking indicators in agricultural field soils is warranted to assess the influence of soil type and agronomic practice on the differential decay of relevant markers and the likelihood of transport in runoff.

  11. Application of particle size distributions to total particulate stack samples to estimate PM2.5 and PM10 emission factors for agricultural sources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Particle size distributions (PSD) have long been used to more accurately estimate the PM10 fraction of total particulate matter (PM) stack samples taken from agricultural sources. These PSD analyses were typically conducted using a Coulter Counter with 50 micrometer aperture tube. With recent increa...

  12. Integrated pest management: the push-pull approach for controlling insect pests and weeds of cereals, and its potential for other agricultural systems including animal husbandry.

    PubMed

    Hassanali, Ahmed; Herren, Hans; Khan, Zeyaur R; Pickett, John A; Woodcock, Christine M

    2008-02-12

    This paper describes the 'push-pull' or 'stimulo-deterrent diversionary' strategy in relation to current and potential examples from our own experiences. The push-pull effect is established by exploiting semiochemicals to repel insect pests from the crop ('push') and to attract them into trap crops ('pull'). The systems exemplified here have been developed for subsistence farming in Africa and delivery of the semiochemicals is entirely by companion cropping, i.e. intercropping for the push and trap cropping for the pull. The main target was a series of lepidopterous pests attacking maize and other cereals. Although the area given to the cereal crop itself is reduced under the push-pull system, higher yields are produced per unit area. An important spin-off from the project is that the companion crops are valuable forage for farm animals. Leguminous intercrops also provide advantages with regard to plant nutrition and some of the trap crops help with water retention and in reducing land erosion. A major benefit is that certain intercrop plants provide dramatic control of the African witchweed (striga). Animal husbandry forms an essential part of intensive subsistence agriculture in Africa and developments using analogous push-pull control strategies for insect pests of cattle are exemplified.

  13. The Use of LiDAR Elevation Data and Satellite Imagery to Locate Critical Source Areas to Diffuse Pollution in Agricultural Watersheds

    NASA Astrophysics Data System (ADS)

    Drouin, Ariane; Michaud, Aubert; Thériault, Georges; Beaudin, Isabelle; Rodrigue, Jean-François; Denault, Jean-Thomas; Desjardins, Jacques; Côté, Noémi

    2013-04-01

    In Quebec / Canada, water quality improvement in rural areas greatly depends on the reduction of diffuse pollution. Indeed, point source pollution has been reduced significantly in Canada in recent years by creating circumscribed pits for manure and removing animals from stream. Diffuse pollution differs from point source pollution because it is spread over large areas. In agricultural areas, sediment loss by soil and riverbank erosion along with loss of nutrients (phosphorus, nitrogen, etc.) and pesticides from fields represent the main source of non-point source pollution. The factor mainly responsible for diffuse pollution in agricultural areas is surface runoff occurring in poorly drained areas in fields. The presence of these poorly drained areas is also one of the most limiting factors in crop productivity. Thus, a reconciliation of objectives at the farm (financial concern for farmers) and off-farm concerns (environmental concern) is possible. In short, drainage, runoff, erosion, water quality and crop production are all interconnected issues that need to be tackled together. Two complementary data sources are mainly used in the diagnosis of drainage, surface runoff and erosion : elevation data and multispectral satellite images. In this study of two watersheds located in Québec (Canada), LiDAR elevation data and satellite imagery (QuickBird, Spot and Landsat) were acquired. The studied territories have been partitioned in hydrologic response units (HRUs) according to sub-basins, soils, elevation (topographic index) and land use. These HRUs are afterwards used in a P index software (P-Edit) that calculates the quantities of sediments and phosphorus exported from each HRUs. These exports of sediments and phosphorus are validated with hydrometric and water quality data obtain in two sub-basins and are also compared to soil brightness index derived from multispectral images. This index is sensitive to soil moisture and thus highlights areas where the soil is

  14. High-frequency monitoring reveals nutrient sources and transport processes in an agriculture-dominated lowland water system

    NASA Astrophysics Data System (ADS)

    van der Grift, Bas; Broers, Hans Peter; Berendrecht, Wilbert; Rozemeijer, Joachim; Osté, Leonard; Griffioen, Jasper

    2016-05-01

    Many agriculture-dominated lowland water systems worldwide suffer from eutrophication caused by high nutrient loads. Insight in the hydrochemical functioning of embanked polder catchments is highly relevant for improving the water quality in such areas or for reducing export loads to downstream water bodies. This paper introduces new insights in nutrient sources and transport processes in a polder in the Netherlands situated below sea level using high-frequency monitoring technology at the outlet, where the water is pumped into a higher situated lake, combined with a low-frequency water quality monitoring programme at six locations within the drainage area. Seasonal trends and short-scale temporal dynamics in concentrations indicated that the NO3 concentration at the pumping station originated from N loss from agricultural lands. The NO3 loads appear as losses via tube drains after intensive rainfall events during the winter months due to preferential flow through the cracked clay soil. Transfer function-noise modelling of hourly NO3 concentrations reveals that a large part of the dynamics in NO3 concentrations during the winter months can be related to rainfall. The total phosphorus (TP) concentration and turbidity almost doubled during operation of the pumping station, which points to resuspension of particulate P from channel bed sediments induced by changes in water flow due to pumping. Rainfall events that caused peaks in NO3 concentrations did not results in TP concentration peaks. The rainfall induced and NO3 enriched quick interflow, may also be enriched in TP but retention of TP due to sedimentation of particulate P then results in the absence of rainfall induced TP concentration peaks. Increased TP concentrations associated with run-off events is only observed during a rainfall event at the end of a freeze-thaw cycle. All these observations suggest that the P retention potential of polder water systems is primarily due to the artificial pumping regime

  15. High-frequency monitoring reveals nutrient sources and transport processes in an agriculture-dominated lowland water system

    NASA Astrophysics Data System (ADS)

    van der Grift, B.; Broers, H. P.; Berendrecht, W. L.; Rozemeijer, J. C.; Osté, L. A.; Griffioen, J.

    2015-08-01

    Many agriculture-dominated lowland water systems worldwide suffer from eutrophication caused by high nutrient loads. Insight in the hydrochemical functioning of embanked polder catchments is highly relevant for improving the water quality in such areas. This paper introduces new insights in nutrient sources and transport processes in a low elevated polder in the Netherlands using high-frequency monitoring technology at the outlet, where the water is pumped into a higher situated lake, combined with a low-frequency water quality monitoring program at six locations within the drainage area. Seasonal trends and short scale temporal dynamics in concentrations indicated that the NO3 concentration at the pumping station originated from N-loss from agricultural lands. The NO3 loads appear as losses with drain water discharge after intensive rainfall events during the winter months due to preferential flow through the cracked clay soil. Transfer function-noise modelling of hourly NO3 concentrations reveals that a large part of the dynamics in NO3 concentrations during the winter months can be related to rainfall. The total phosphorus (TP) concentration almost doubled during operation of the pumping station which points to resuspension of particulate P from channel bed sediments induced by changes in water flow due to pumping. Rainfall events that caused peaks in NO3 concentrations did not results in TP concentration peaks. The by rainfall induced and NO3 enriched quick interflow, may also be enriched in TP but this is then buffered in the water system due to sedimentation of particulate P. Increased TP concentrations associated with run-off events is only observed during a rainfall event at the end of a freeze-thaw cycle. All these observations suggest that the P retention potential of polder water systems is highly due to the artificial pumping regime that buffers high flows. As the TP concentration is affected by operation of the pumping station, timing of sampling

  16. Development of a risk-based index for source water protection planning, which supports the reduction of pathogens from agricultural activity entering water resources.

    PubMed

    Goss, Michael; Richards, Charlene

    2008-06-01

    Source water protection planning (SWPP) is an approach to prevent contamination of ground and surface water in watersheds where these resources may be abstracted for drinking or used for recreation. For SWPP the hazards within a watershed that could contribute to water contamination are identified together with the pathways that link them to the water resource. In rural areas, farms are significant potential sources of pathogens. A risk-based index can be used to support the assessment of the potential for contamination following guidelines on safety and operational efficacy of processes and practices developed as beneficial approaches to agricultural land management. Evaluation of the health risk for a target population requires knowledge of the strength of the hazard with respect to the pathogen load (massxconcentration). Manure handling and on-site wastewater treatment systems form the most important hazards, and both can comprise confined and unconfined source elements. There is also a need to understand the modification of pathogen numbers (attenuation) together with characteristics of the established pathways (surface or subsurface), which allow the movement of the contaminant species from a source to a receptor (water source). Many practices for manure management have not been fully evaluated for their impact on pathogen survival and transport in the environment. A key component is the identification of potential pathways of contaminant transport. This requires the development of a suitable digital elevation model of the watershed for surface movement and information on local groundwater aquifer systems for subsurface flows. Both require detailed soils and geological information. The pathways to surface and groundwater resources can then be identified. Details of land management, farm management practices (including animal and manure management) and agronomic practices have to be obtained, possibly from questionnaires completed by each producer within the

  17. A Glossary of Spanish-American Agricultural Terms.

    ERIC Educational Resources Information Center

    Mainous, Bruce H.; Rund, Maria T.

    The Spanish-English and English-Spanish glossary of agricultural and supporting terms is an expansion of an earlier glossary intended for North American agricultural specialists working in Latin America. It contains terminology from 50 articles in Spanish on Latin American agricultural topics. A list of those sources is included. (MSE)

  18. Descriptions and Source Listings of Professional Information in Agricultural Education, 1966-67, 1967-68, and 1968-69.

    ERIC Educational Resources Information Center

    American Vocational Association, Washington, DC. Professional Information Committee.

    These annotated bibliographies contain a total of 449 references of professional information in agricultural education published annually. References are organized under headings of: (1) Agricultural Mechanics, (2) Animal Science, (3) Conservation and Forestry, (4) Curriculum Development and Course of Study, (5) Farm Business Management and…

  19. Forests on drained agricultural peatland are potentially large sources of greenhouse gases - insights from a full rotation period simulation

    NASA Astrophysics Data System (ADS)

    He, Hongxing; Jansson, Per-Erik; Svensson, Magnus; Björklund, Jesper; Tarvainen, Lasse; Klemedtsson, Leif; Kasimir, Åsa

    2016-04-01

    The CoupModel was used to simulate a Norway Spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring derived biomass data and measured 6 year abiotic data we obtained a "reference" model by which we were able to describe the GHG fluxes and controlling factors over the 60 years. The GHG fluxes are composed of two important quantities, the forest carbon (C) uptake, 405 g C m‑2 yr‑1 and the decomposition of peat soil, 396 g C m‑2 yr‑1. N2O emissions contribute to the GHG emissions by 0.5 g N m‑2 yr‑1, corresponding to 56.8 g C m‑2 yr‑1. The 60-year-old Spruce forest has an accumulated biomass of 164 Mg C ha‑1. However, over this period 208 Mg C ha‑1 GHG has been added to the atmosphere, which means a net addition of GHG emissions. The main losses are from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. Model sensitivity analysis by changing initial soil C, drainage depth and initial soil C/N ratio also confirms that forests on drained agricultural peatland are a GHG source. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding both CO2 and N2O to the atmosphere.

  20. Identification of sources and behavior of agricultural contaminants in groundwater using nitorgen and sulfur isootope in Haean basin, Korea

    NASA Astrophysics Data System (ADS)

    Kaown, Dugin; Kim, Heejung; Mayer, Bernard; Hyun, Yunjung; Lee, Jin-Yong; Lee, Kang-Kun

    2013-04-01

    The Haean basin shows a bowl-shaped topographic feature and the drainage system shows a dendritic pattern. The study area is consisted of forests (58.0%), vegetable fields (27.6%), rice paddy fields (11.4%) and fruit fields (0.5%). Most of residents in the study area practice agriculture and paddy rice and vegetables (Chinese radish) are the typical crops grown. The concentration of nitrate in groundwater showed 0.8 ~ 67.3 mg/L in June, 2012 and 2.0 ~ 65.7 mg/L in September, 2012. Hydrogeochemical values and stable isotope ratios of dissolved nitrate and sulfate in groundwater were used to identify contamination sources and transformation processes in shallow groundwater. The δ15N-NO3- values in the study area ranged between +5.2 and +16.9‰ in June and between +4.4 and +13.0‰ in September. The sulfate concentration in groundwater samples obtained from the study area varied from 0.8 to 16.5 mg/L in June and 0 to 19.7 mg/L in September. δ34S-SO42- values ranged from +2.9 to +11.7‰ in June and +1.6 to +8.2‰ in September. The values of δ15N-NO3- and δ34S-SO42- in September were slightly decreased than those of values in June. The chemical composition of groundwater in vegetable and fruit fields showed slightly lower values of δ34S-SO42- and δ15N-NO3- indicated that a mixture of synthetic and organic fertilizers is responsible for groundwater contamination with agro-chemicals. Most groundwater from forests and paddy fields showed slightly higher values of δ15N-NO3- suggested that organic fertilizer is introduced into subsurface.

  1. Forests on drained agricultural peatland are potentially large sources of greenhouse gases - insights from a full rotation period simulation

    NASA Astrophysics Data System (ADS)

    He, Hongxing; Jansson, Per-Erik; Svensson, Magnus; Björklund, Jesper; Tarvainen, Lasse; Klemedtsson, Leif; Kasimir, Åsa

    2016-04-01

    The CoupModel was used to simulate a Norway Spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring derived biomass data and measured 6 year abiotic data we obtained a "reference" model by which we were able to describe the GHG fluxes and controlling factors over the 60 years. The GHG fluxes are composed of two important quantities, the forest carbon (C) uptake, 405 g C m-2 yr-1 and the decomposition of peat soil, 396 g C m-2 yr-1. N2O emissions contribute to the GHG emissions by 0.5 g N m-2 yr-1, corresponding to 56.8 g C m-2 yr-1. The 60-year-old Spruce forest has an accumulated biomass of 164 Mg C ha-1. However, over this period 208 Mg C ha-1 GHG has been added to the atmosphere, which means a net addition of GHG emissions. The main losses are from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. Model sensitivity analysis by changing initial soil C, drainage depth and initial soil C/N ratio also confirms that forests on drained agricultural peatland are a GHG source. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding both CO2 and N2O to the atmosphere.

  2. Land-use controls on sources and fate of nitrate in shallow groundwater of an agricultural area revealed by multiple environmental tracers

    NASA Astrophysics Data System (ADS)

    Koh, Dong-Chan; Mayer, Bernhard; Lee, Kwang-Sik; Ko, Kyung-Seok,

    2010-10-01

    Sources and transformation processes of nitrate in groundwater from shallow aquifers were investigated in an agricultural area in the mid-western part of South Korea using a multi-tracer approach including δ 2H and δ 18O values of water, δ 15N and δ 18O values of nitrate, Cl/Br ratios and chlorofluorocarbons (CFCs). The study area was comprised of four land-use types with natural areas at higher altitudes, upland areas with fruit orchards, paddy fields and residential areas at lower elevations. The isotopic composition of water was suitable for distinguishing groundwater that had infiltrated in the higher elevation natural areas with lower δ 2H and δ 18O values from groundwater underneath paddy fields that was characterized by elevated δ 2H and δ 18O values due to evaporation. δ 18O-H 2O values and Cl - concentrations indicated that groundwater and contaminant sources were derived from three land-use types: natural areas, residential areas and paddy fields. Groundwater age determination based on CFCs showed that nitrate contamination of groundwater is primarily controlled by historic nitrogen loadings at least in areas with higher nitrate contamination. Nitrate sources were identified using the stable isotope composition of nitrate and Cl/Br ratios. Higher δ 15N-NO 3- values and Cl/Br ratios of 300 to 800 in residential areas indicated that waste water and septic effluents were major nitrate sources whereas lower δ 15N-NO 3- values and Cl/Br ratios of 100 to 700 in upland areas suggested that synthetic fertilizers constituted a major source of nitrate contamination of aquifers. With only few exceptions in the natural area, contributions of atmospheric nitrate were insignificant due to the resetting of δ 18O-NO 3- values via immobilization and re-mineralization of nitrate in the soil zone. In groundwater underneath paddy fields, 30% of samples had δ 18O-NO 3- values at least 2‰ higher than expected for nitrate formed by chemolithoautotrophic

  3. Land-use controls on sources and fate of nitrate in shallow groundwater of an agricultural area revealed by multiple environmental tracers.

    PubMed

    Koh, Dong-Chan; Mayer, Bernhard; Lee, Kwang-Sik; Ko, Kyung-Seok

    2010-10-21

    Sources and transformation processes of nitrate in groundwater from shallow aquifers were investigated in an agricultural area in the mid-western part of South Korea using a multi-tracer approach including δ²H and δ¹⁸O values of water, δ¹⁵N and δ¹⁸O values of nitrate, Cl/Br ratios and chlorofluorocarbons (CFCs). The study area was comprised of four land-use types with natural areas at higher altitudes, upland areas with fruit orchards, paddy fields and residential areas at lower elevations. The isotopic composition of water was suitable for distinguishing groundwater that had infiltrated in the higher elevation natural areas with lower δ²H and δ¹⁸O values from groundwater underneath paddy fields that was characterized by elevated δ²H and δ¹⁸O values due to evaporation. δ¹⁸O-H₂O values and Cl⁻ concentrations indicated that groundwater and contaminant sources were derived from three land-use types: natural areas, residential areas and paddy fields. Groundwater age determination based on CFCs showed that nitrate contamination of groundwater is primarily controlled by historic nitrogen loadings at least in areas with higher nitrate contamination. Nitrate sources were identified using the stable isotope composition of nitrate and Cl/Br ratios. Higher δ¹⁵N-NO₃⁻ values and Cl/Br ratios of 300 to 800 in residential areas indicated that waste water and septic effluents were major nitrate sources whereas lower δ¹⁵N-NO₃⁻ values and Cl/Br ratios of 100 to 700 in upland areas suggested that synthetic fertilizers constituted a major source of nitrate contamination of aquifers. With only few exceptions in the natural area, contributions of atmospheric nitrate were insignificant due to the resetting of δ¹⁸O-NO₃⁻ values via immobilization and re-mineralization of nitrate in the soil zone. In groundwater underneath paddy fields, 30% of samples had δ¹⁸O-NO₃⁻ values at least 2‰ higher than expected for nitrate formed

  4. Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    PubMed Central

    Gibbs, H. K.; Ruesch, A. S.; Achard, F.; Clayton, M. K.; Holmgren, P.; Ramankutty, N.; Foley, J. A.

    2010-01-01

    Global demand for agricultural products such as food, feed, and fuel is now a major driver of cropland and pasture expansion across much of the developing world. Whether these new agricultural lands replace forests, degraded forests, or grasslands greatly influences the environmental consequences of expansion. Although the general pattern is known, there still is no definitive quantification of these land-cover changes. Here we analyze the rich, pan-tropical database of classified Landsat scenes created by the Food and Agricultural Organization of the United Nations to examine pathways of agricultural expansion across the major tropical forest regions in the 1980s and 1990s and use this information to highlight the future land conversions that probably will be needed to meet mounting demand for agricultural products. Across the tropics, we find that between 1980 and 2000 more than 55% of new agricultural land came at the expense of intact forests, and another 28% came from disturbed forests. This study underscores the potential consequences of unabated agricultural expansion for forest conservation and carbon emissions. PMID:20807750

  5. Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s.

    PubMed

    Gibbs, H K; Ruesch, A S; Achard, F; Clayton, M K; Holmgren, P; Ramankutty, N; Foley, J A

    2010-09-21

    Global demand for agricultural products such as food, feed, and fuel is now a major driver of cropland and pasture expansion across much of the developing world. Whether these new agricultural lands replace forests, degraded forests, or grasslands greatly influences the environmental consequences of expansion. Although the general pattern is known, there still is no definitive quantification of these land-cover changes. Here we analyze the rich, pan-tropical database of classified Landsat scenes created by the Food and Agricultural Organization of the United Nations to examine pathways of agricultural expansion across the major tropical forest regions in the 1980s and 1990s and use this information to highlight the future land conversions that probably will be needed to meet mounting demand for agricultural products. Across the tropics, we find that between 1980 and 2000 more than 55% of new agricultural land came at the expense of intact forests, and another 28% came from disturbed forests. This study underscores the potential consequences of unabated agricultural expansion for forest conservation and carbon emissions. PMID:20807750

  6. Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s.

    PubMed

    Gibbs, H K; Ruesch, A S; Achard, F; Clayton, M K; Holmgren, P; Ramankutty, N; Foley, J A

    2010-09-21

    Global demand for agricultural products such as food, feed, and fuel is now a major driver of cropland and pasture expansion across much of the developing world. Whether these new agricultural lands replace forests, degraded forests, or grasslands greatly influences the environmental consequences of expansion. Although the general pattern is known, there still is no definitive quantification of these land-cover changes. Here we analyze the rich, pan-tropical database of classified Landsat scenes created by the Food and Agricultural Organization of the United Nations to examine pathways of agricultural expansion across the major tropical forest regions in the 1980s and 1990s and use this information to highlight the future land conversions that probably will be needed to meet mounting demand for agricultural products. Across the tropics, we find that between 1980 and 2000 more than 55% of new agricultural land came at the expense of intact forests, and another 28% came from disturbed forests. This study underscores the potential consequences of unabated agricultural expansion for forest conservation and carbon emissions.

  7. Identifying sources of dissolved organic carbon in agriculturally dominated rivers using radiocarbon age dating: Sacramento-San Joaquin River Basin, California

    USGS Publications Warehouse

    Sickman, James O.; DiGiorgio, Carol L.; Davisson, M. Lee; Lucero, Delores M.; Bergamaschi, Brian A.

    2010-01-01

    We used radiocarbon measurements of dissolved organic carbon (DOC) to resolve sources of riverine carbon within agriculturally dominated landscapes in California. During 2003 and 2004, average Δ14C for DOC was -254‰ in agricultural drains in the Sacramento-San Joaquin Delta, -218‰ in the San Joaquin River, -175‰ in the California State Water Project and -152‰ in the Sacramento River. The age of bulk DOC transiting the rivers of California's Central Valley is the oldest reported for large rivers and suggests wide-spread loss of soil organic matter caused by agriculture and urbanization. Using DAX 8 adsorbent, we isolated and measured 14C concentrations in hydrophobic acid fractions (HPOA); river samples showed evidence of bomb-pulse carbon with average Δ14C of 91 and 76‰ for the San Joaquin and Sacramento Rivers, respectively, with older HPOA, -204‰, observed in agricultural drains. An operationally defined non-HPOA fraction of DOC was observed in the San Joaquin River with seasonally computed Δ14C values of between -275 and -687‰; the source of this aged material was hypothesized to be physically protected organic-matter in high clay-content soils and agrochemicals (i.e., radiocarbon-dead material) applied to farmlands. Mixing models suggest that the Sacramento River contributes about 50% of the DOC load in the California State Water Project, and agricultural drains contribute approximately one-third of the load. In contrast to studies showing stabilization of soil carbon pools within one or two decades following land conversion, sustained loss of soil organic matter, occurring many decades after the initial agricultural-land conversion, was observed in California's Central Valley.

  8. Long-term Observations of Carbonaceous Aerosols (including C isotope) at Alert: Inferring Emission Sources of Black Carbon Transported to the Arctic

    NASA Astrophysics Data System (ADS)

    Huang, Lin; Sharma, Sangeeta; Zhang, Wendy; Brook, Jeff; Leaitch, Richard; He, Kebin; Duan, Fengkui; Yang, Fumo

    2015-04-01

    Black carbon is a major component of carbonaceous aerosols and formed by incomplete combustion of fossil fuels and biomass burning (including biofuels and open fires). It plays unique roles in Earth's climate system through both direct and indirect effects. Identifying and attributing its emission sources, tracking source changes with time and relating them to radiative forcing are important for understanding the impacts of BC on climate at the global and regional levels, as well as necessary for the strategies targeted to reduce BC emission. However, there are many challenges and uncertainties regarding those aspects, particularly for BC aerosols transported to the Arctic region. To address the concerns of BC in the Arctic, carbonaceous aerosol observations, including elemental carbon (EC) content as BC mass, C isotopes as a source tracer, and light absorption coefficient as BC's optical property, have been conducted at Alert, a WMO GAW station (82° 27'N, 62° 31'W) since the early 2000s. In this presentation, nearly a decade of measurements will be presented, with a focus on the isotope results in EC (corresponding data from Beijing will also be shown for the purpose of comparison). Seasonal and inter-annual variations in δ13C (EC) have been characterized, inferring emission sources and suggesting source changes over last 5-6 years. Based on the C isotope results, the possible emission sources of BC contributed to the Arctic will be also discussed.

  9. Tracing organic and inorganic pollution sources of agricultural crops and water resources in Güzelhisar Basin of the Aegean Region - Turkey

    NASA Astrophysics Data System (ADS)

    Czarnecki, Sezin; Colak Esetlili, Bihter; Esetlili, Tolga; Tepecik, Mahmut; Anac, Dilek; Düring, Rolf-Alexander

    2014-05-01

    The study area Güzelhisar Basin is 6 km far from the city Aliaga, Aegean Region in Turkey which represents a rather industrialized area having five large iron and steel factories, but also areas of agriculture. Steel industry in Aliaga is causing metal pollution. Around Güzelhisar Basin and nearby, the dominant crop fields are cotton, maize, vegetables, olive trees and vineyards. Güzelhisar stream and dam water is used for irrigation of the agricultural land. Due to contamination from metal industry in Aliaga, organic farming is not allowed in this region. Industrial activities in the region present a threat on sustainable agriculture. The region is a multi-impacted area in terms of several pollutant sources affecting soil and water quality. The overall objective of the project is to trace back plant nutrients (N, P, K, Ca, Mg, Na, Fe, Mn, Zn, Cu, and B), hazardous substances (i. e. persistent organic pollutants), radionuclides (40K, 232Th, 226Ra/238U), and metal contents (As, Cd, Cr, Co, Cu, Hg, Mn, Ni, Pb, and Zn) by examining the soils, agricultural crops and natural plants from Güzelhisar Basin and water and sediments from Güzelhisar stream and dam. Spatial distribution of pollution will be evaluated by regionalization methods. For this, an advanced analytical methodology will be applied which provides an understanding of sources and occurrence of the respective substances of concern. An innovative multi-tracer approach comprising organic and inorganic marker substances, will identify and quantitatively assess sources and their impact on water pollution and the pollutant pathways in this agricultural crop production system.

  10. Monthly variability and possible sources of nitrate in ground water beneath mixed agricultural land use, Suwannee and Lafayette Counties, Florida

    USGS Publications Warehouse

    Katz, Brian G.; Böhlke, J.K.

    2000-01-01

    In an area of mixed agricultural land use in Suwannee and Lafayette Counties of northern Florida, water samples were collected monthly from 14 wells tapping the Upper Floridan aquifer during July 1998 through June 1999 to assess hydrologic and land-use factors affecting the variability in nitrate concentrations in ground water. Unusually high amounts of rainfall in September and October 1998 (43.5 centimeters total for both months) resulted in an increase in water levels in all wells in October 1998. This was followed by unusually low amounts of rainfall during November 1998 through May 1999, when rainfall was 40.7 centimeters below 30-year mean monthly values. The presence of karst features (sinkholes, springs, solution conduits) and the highly permeable sands that overlie the Upper Floridan aquifer provide for rapid movement of water containing elevated nitrate concentrations to the aquifer. Nitrate was the dominant form of nitrogen in ground water collected at all sites and nitrate concentrations ranged from less than 0.02 to 22 milligrams per liter (mg/L), as nitrogen. Water samples from most wells showed substantial monthly or seasonal fluctuations in nitrate concentrations. Generally, water samples from wells with nitrate concentrations higher than 10 mg/L showed the greatest amount of monthly fluctuation. For example, water samples from six of eight wells had monthly nitrate concentrations that varied by at least 5 mg/L during the study period. Water from most wells with lower nitrate concentrations (less than 6 mg/L) also showed large monthly fluctuations. For instance, nitrate concentrations in water from four sites showed monthly variations of more than 50 percent. Large fluctuations in nitrate concentrations likely result from seasonal agricultural practices (fertilizer application and animal waste spreading) at a particular site. For example, an increase in nitrate concentrations observed in water samples from seven sites in February or March 1999 most

  11. A simulation-based interval two-stage stochastic model for agricultural non-point source pollution control through land retirement.

    PubMed

    Luo, B; Li, J B; Huang, G H; Li, H L

    2006-05-15

    This study presents a simulation-based interval two-stage stochastic programming (SITSP) model for agricultural non-point source (NPS) pollution control through land retirement under uncertain conditions. The modeling framework was established by the development of an interval two-stage stochastic program, with its random parameters being provided by the statistical analysis of the simulation outcomes of a distributed water quality approach. The developed model can deal with the tradeoff between agricultural revenue and "off-site" water quality concern under random effluent discharge for a land retirement scheme through minimizing the expected value of long-term total economic and environmental cost. In addition, the uncertainties presented as interval numbers in the agriculture-water system can be effectively quantified with the interval programming. By subdividing the whole agricultural watershed into different zones, the most pollution-related sensitive cropland can be identified and an optimal land retirement scheme can be obtained through the modeling approach. The developed method was applied to the Swift Current Creek watershed in Canada for soil erosion control through land retirement. The Hydrological Simulation Program-FORTRAN (HSPF) was used to simulate the sediment information for this case study. Obtained results indicate that the total economic and environmental cost of the entire agriculture-water system can be limited within an interval value for the optimal land retirement schemes. Meanwhile, a best and worst land retirement scheme was obtained for the study watershed under various uncertainties.

  12. Nonpoint-source agricultural chemicals in ground water in Nebraska; preliminary results for six areas of the High Plains Aquifer

    USGS Publications Warehouse

    Chen, Hsiu-Hsiung; Druliner, A.D.

    1987-01-01

    The reconnaissance phase of a study to determine the occurrence of agricultural chemicals from nonpoint sources in groundwater in six areas, which represented the major provinces of the High Plains aquifer in Nebraska is described. In 1984, water from 82 wells in the 6 study areas was analyzed for nitrate, and water from 57 of the 82 wells was analyzed for triazine herbicides. Data for 9 of the 21 independent variables suspected of affecting concentrations of nitrate and triazine herbicides in groundwater were compiled from the 82 well sites. The variables and their ranges are: hydraulic gradient (XI), 0.006-0.0053; hydraulic conductivity (X2), 5-149 ft/day; specific discharge (X3), 0.0128-0.2998 ft/day; depth to water (X4), 3-239 ft; well depth (X5), 40-550 ft; annual precipitation (X6), 12.0-39.3 inches; soil permeability (X7), 0.76-9.0 inches; irrigation well density (X8), 0-8 irrigation wells/ sq mi; and annual nitrogen fertilizer use (X9), 0-260 lbs of nitrogen/acre. Nitrate concentrations ranged from < 0.1 to 45 mg/L as nitrogen. Triazine herbicide concentrations were detected in samples from five of the six study areas in concentrations ranging from < 0.1 to 2.3 mg/L. Statistical tests indicated that there were significant differences in nitrate concentrations among the six study areas, while no significant differences in triazine herbicide concentrations were found. Concentrations of nitrate and triazine herbicide were significantly larger in more intensively irrigated areas. Preliminary correlations with the independent variables and nitrate concentrations indicated significant relations at the 95% confidence level with variables X2, X5, and X8. Correlations with triazine herbicide concentrations indicated significant relations with variables X2 , X3, X5, X6, and X8, and with nitrate concentrations (X10). By using a simple multiple regression technique, variables X5, X8, and X9 explained about 51% of the variation in nitrate concentrations. Variables X3

  13. A revised dosimetric characterization of the model S700 electronic brachytherapy source containing an anode-centering plastic insert and other components not included in the 2006 model

    SciTech Connect

    Hiatt, Jessica R.; Davis, Stephen D.; Rivard, Mark J.

    2015-06-15

    Purpose: The model S700 Axxent electronic brachytherapy source by Xoft, Inc., was characterized by Rivard et al. in 2006. Since then, the source design was modified to include a new insert at the source tip. Current study objectives were to establish an accurate source model for simulation purposes, dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and determine dose differences between the original simulation model and the current model S700 source design. Methods: Design information from measurements of dissected model S700 sources and from vendor-supplied CAD drawings was used to aid establishment of an updated Monte Carlo source model, which included the complex-shaped plastic source-centering insert intended to promote water flow for cooling the source anode. These data were used to create a model for subsequent radiation transport simulations in a water phantom. Compared to the 2006 simulation geometry, the influence of volume averaging close to the source was substantially reduced. A track-length estimator was used to evaluate collision kerma as a function of radial distance and polar angle for determination of TG-43 dosimetry parameters. Results for the 50 kV source were determined every 0.1 cm from 0.3 to 15 cm and every 1° from 0° to 180°. Photon spectra in water with 0.1 keV resolution were also obtained from 0.5 to 15 cm and polar angles from 0° to 165°. Simulations were run for 10{sup 10} histories, resulting in statistical uncertainties on the transverse plane of 0.04% at r = 1 cm and 0.06% at r = 5 cm. Results: The dose-rate distribution ratio for the model S700 source as compared to the 2006 model exceeded unity by more than 5% for roughly one quarter of the solid angle surrounding the source, i.e., θ ≥ 120°. The radial dose function diminished in a similar manner as for an {sup 125}I seed, with values of 1.434, 0.636, 0.283, and 0.0975 at 0.5, 2, 5, and 10 cm, respectively. The radial dose

  14. Towards an improved inventory of N2O from agriculture: Model evaluation of N2O emission factors and N fraction leached from different sources in UK agriculture

    NASA Astrophysics Data System (ADS)

    Cardenas, L. M.; Gooday, R.; Brown, L.; Scholefield, D.; Cuttle, S.; Gilhespy, S.; Matthews, R.; Misselbrook, T.; Wang, J.; Li, C.; Hughes, G.; Lord, E.

    2013-11-01

    National and international requirements for greenhouse gas emissions demand the development of more accurate inventories and mitigation options that are effective in reducing emissions. The UK government set a target for the year 2050 of an 80% reduction in greenhouse gas emissions compared to the 1990 baseline. Estimate of UK national emissions is based on IPCC default methodology and as agriculture contributes about 7% of total GHG emissions of which 60% is N2O, efforts to improve the inventory and assess mitigation options are needed. Models can be used to derive N2O emission factors providing high spatial and temporal resolution. In this study, we used two models, the UK-DNDC, a mechanistic model to estimate N2O emissions from soils and the NITCAT model to estimate the fraction of N applied that is leached and causes indirect emissions, both at county level for the UK. Four mitigation options were assessed and the results showed there were differences in the emission factors according to location. Average emission factors for N2O from soils for inorganic fertiliser did not differ from the IPCC default value but for organic fertiliser the model gave much lower values. FracLEACH for arable land was higher than that for grassland (UK averages of 0.28 and 0.09 respectively) and the national average value was 0.18. For N2O, the most effective mitigation measure was adjusting fertiliser rates to account for crop available manure N. For N leaching, the most effective measure was implementation of a manure closed period.

  15. Near-Channel Sediment Sources Now Dominate in Many Agricultural Landscapes: The Emergence of River-Network Models to Guide Watershed Management

    NASA Astrophysics Data System (ADS)

    Czuba, J. A.; Foufoula-Georgiou, E.; Gran, K. B.; Belmont, P.; Wilcock, P. R.

    2015-12-01

    Detailed sediment budgets for many agricultural watersheds are revealing a surprising story - that sediment is no longer primarily sourced from upland fields, but instead from near-channel sources. This is the case for the Minnesota River Basin (MRB) where an intensification and expansion of agricultural drainage combined with increased precipitation has (1) reduced surface runoff and erosion, (2) amplified streamflows, and (3) accelerated both near-channel sediment generation and sediment transport. Bluffs and streambanks in the MRB are now the dominant sources of sediment, but these features are not easily incorporated into traditional watershed-scale, sediment-transport models. Instead, we are advancing a network-based modeling framework that explicitly considers sediment sources, transport, and storage along a river network. We apply this framework to bed-material sediment transport in the Greater Blue Earth River Basin, the major sediment-generating subbasin of the MRB, where a recent sediment budget has quantified the locations and rates of erosion and deposition of major sediment sources and sinks (i.e., bluffs, streambanks/floodplains, agricultural fields, and ravines) over millennial and decadal timescales. With the river network as the basis of a simple model, inputs of sediment to the network are informed by the sediment budget and these inputs are tracked through the network using process-based time delays that incorporate uniform-flow hydraulics and at-capacity sediment transport. We explore how this sediment might move through the network and affect the variability of bed elevations under cases where the mechanisms of in-channel and floodplain storage are turned on and off. We will discuss timescales of movement of sediment through the system to better inform legacy effects and hysteresis, and also discuss targeted management actions that will most effectively reduce the detrimental effects of excess sediment.

  16. Handbook of Agricultural Geophysics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Geophysical methods continue to show great promise for use in agriculture. The term “agricultural geophysics” denotes a subdiscipline of geophysics that is focused only on agricultural applications. The Handbook of Agricultural Geophysics was compiled to include a comprehensive overview of the geoph...

  17. Agricultural Occupations Programs Planning Guides

    ERIC Educational Resources Information Center

    Stitt, Thomas R.; And Others

    1977-01-01

    A set of program planning guides that include seven areas (1) Agricultural Production, (2) Agricultural Supplies and Services, (3) Agricultural Mechanics, (4) Agricultural Products, (5) Ornamental Horticulture, (6) Agricultural Resources, and (7) Forestry, were developed and introduced to high school applied biological and agricultural occupations…

  18. Expressing the sense of the House of Representatives that specialty crops are a vital part of agriculture in the United States, that the Committee on Agriculture should propose funding for programs that support specialty crops priorities, and that legislation should be passed that includes funding reflecting specialty crops as a growing and important part of United States agriculture.

    THOMAS, 113th Congress

    Rep. DelBene, Suzan K. [D-WA-1

    2013-04-25

    05/03/2013 Referred to the Subcommittee on Horticulture, Research, Biotechnology, and Foreign Agriculture. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  19. Wastewater Reuse for Agriculture: Development of a Regional Water Reuse Decision-Support Model (RWRM) for Cost-Effective Irrigation Sources.

    PubMed

    Tran, Quynh K; Schwabe, Kurt A; Jassby, David

    2016-09-01

    Water scarcity has become a critical problem in many semiarid and arid regions. The single largest water use in such regions is for crop irrigation, which typically relies on groundwater and surface water sources. With increasing stress on these traditional water sources, it is important to consider alternative irrigation sources for areas with limited freshwater resources. One potential irrigation water resource is treated wastewater for agricultural fields located near urban centers. In addition, treated wastewater can contribute an appreciable amount of necessary nutrients for plants. The suitability of reclaimed water for specific applications depends on water quality and usage requirements. The main factors that determine the suitability of recycled water for agricultural irrigation are salinity, heavy metals, and pathogens, which cause adverse effects on human, plants, and soils. In this paper, we develop a regional water reuse decision-support model (RWRM) using the general algebraic modeling system to analyze the cost-effectiveness of alternative treatment trains to generate irrigation water from reclaimed wastewater, with the irrigation water designed to meet crop requirements as well as California's wastewater reuse regulations (Title 22). Using a cost-minimization framework, least-cost solutions consisting of treatment processes and their intensities (blending ratios) are identified to produce alternative irrigation sources for citrus and turfgrass. Our analysis illustrates the benefits of employing an optimization framework and flexible treatment design to identify cost-effective blending opportunities that may produce high-quality irrigation water for a wide range of end uses. PMID:27499353

  20. Wastewater Reuse for Agriculture: Development of a Regional Water Reuse Decision-Support Model (RWRM) for Cost-Effective Irrigation Sources.

    PubMed

    Tran, Quynh K; Schwabe, Kurt A; Jassby, David

    2016-09-01

    Water scarcity has become a critical problem in many semiarid and arid regions. The single largest water use in such regions is for crop irrigation, which typically relies on groundwater and surface water sources. With increasing stress on these traditional water sources, it is important to consider alternative irrigation sources for areas with limited freshwater resources. One potential irrigation water resource is treated wastewater for agricultural fields located near urban centers. In addition, treated wastewater can contribute an appreciable amount of necessary nutrients for plants. The suitability of reclaimed water for specific applications depends on water quality and usage requirements. The main factors that determine the suitability of recycled water for agricultural irrigation are salinity, heavy metals, and pathogens, which cause adverse effects on human, plants, and soils. In this paper, we develop a regional water reuse decision-support model (RWRM) using the general algebraic modeling system to analyze the cost-effectiveness of alternative treatment trains to generate irrigation water from reclaimed wastewater, with the irrigation water designed to meet crop requirements as well as California's wastewater reuse regulations (Title 22). Using a cost-minimization framework, least-cost solutions consisting of treatment processes and their intensities (blending ratios) are identified to produce alternative irrigation sources for citrus and turfgrass. Our analysis illustrates the benefits of employing an optimization framework and flexible treatment design to identify cost-effective blending opportunities that may produce high-quality irrigation water for a wide range of end uses.

  1. Assessing the sources of suspended sediments in the streams of an agricultural watershed in the Canadian prairies using caesium-137 as a tracer

    NASA Astrophysics Data System (ADS)

    Koiter, A. J.; Lobb, D. A.; Owens, P. N.; Tiessen, K. H. D.; Li, S.

    2012-04-01

    Sediments adversely impact the quality of surface waters and are a significant source of contaminants such as nutrients and pesticides in agricultural watersheds. The South Tobacco Creek watershed is part of a national project aimed at measuring the economic and water quality impacts of different agricultural practices and is one of nine sites across Canada. This predominantly agricultural watershed extends across the Manitoba Escarpment; its upper reaches lay in undulating glacial tills and its lower reaches lay in the lacustrine sediments of glacial Lake Agassiz. Past studies of soil erosion within fields and sediment delivery from the watershed have produced conflicting results. In 2009, a comprehensive study of the sources of sediments was undertaken using sediment fingerprinting techniques. Suspended sediments were sampled using paired time-integrated samplers fixed to the stream bed. Samples were collected over the course of three years at several locations along the main stem of the creek, ranging from 3rd order (42 ha) to seventh order (7441 ha) drainage basins. Sediment samples were analyzed for caesium-137 content and the values were compared to those measured within the surface soil of field and riparian areas, and streambank profiles. Analysis determined that the majority of suspended sediments being exported from the watershed were coming from the stream channels and not the soils of the uplands.

  2. Historical accumulation of N and P and sources of organic matter and N in sediment in an agricultural reservoir in Northern China.

    PubMed

    Ni, Zhaokui; Wang, Shengrui; Chu, Zhaosheng; Jin, Xiangcan

    2015-07-01

    Agriculture has significantly intensified in Northern China since the 1980s. This intensification has caused a series of simultaneous lake ecological environment problems in this area. However, little is known about the role of agricultural intensification in historical nutrient dynamics and lake eutrophication processes. The Yanghe reservoir, a typical artificial reservoir characterized by high-yield grain production in Northern China, has been suffering from serious eutrophication and water quality deterioration. This study evaluates the effect of agricultural intensification on nutrient retention and source in the sediments using (210)Pb and (137)Cs dating techniques combined with stable C and N isotopes (δ(13)C, δ(15)N) and total organic carbon/total nitrogen, as well as total nitrogen (TN), total phosphorus (TP), and P fractions. Results suggested that agricultural intensification was keys to the accumulation of nutrients and was a source of organic matter (OM) and N in sediment for the past three decades. N and P pollution started in the 1980s and worsened from the 1990s. Good water quality status and steady sedimentary environment with low nutrient content (mean concentrations of TN and TP were 815 and 387 mg kg(-1), respectively) were observed before the 1980s. Sediment OM was primarily derived from aquatic plants, whereas N was primarily derived from soil erosion and aquatic plants. However, water quality began to deteriorate while sediment nutrient content began to increase after the 1980s, with values of 1186 mg kg(-1) for TN and 434 mg kg(-1) for TP in 1989. Sediment OM was primarily derived from C3 (sweet potato) and aquatic plants, and the major sources of N were soil erosion, fertilizer, and sewage, which accompany the rapid development of agriculture in the watershed. Following the further growth of grain production and fertilizers, excessive external nutrient loading has resulted in dramatic water quality and ecosystem deterioration since 1990

  3. Information for Agricultural Development.

    ERIC Educational Resources Information Center

    Kaungamno, E. E.

    This paper describes the major international agricultural information services, sources, and systems; outlines the existing information situation in Tanzania as it relates to problems of agricultural development; and reviews the improvements in information provision resources required to support the process of agricultural development in Tanzania.…

  4. Indicators of the sources and distribution of nitrate in water from shallow domestic wells in agricultural areas of the New Jersey Coastal Plain

    USGS Publications Warehouse

    Vowinkel, Eric F.; Tapper, Robert J.

    1995-01-01

    Previously collected and new water-quality data from shallow wells (screened interval less than 30 meters below the land surface) in predominantly agricultural areas of the New Jersey Coastal Plain were used to determine the relation of nitrate concentrations in shallow ground water to various hydrogeologic and land-use factors in the study area. Information on land use, well construction, hydrogeology, and water quality were used to predict the conditions under which concentrations of nitrate as nitrogen in water from domestic wells in predominantly agricultural areas are most likely to be equal to or larger than the U.S. Environmental Protection Agency maximum contaminant level (MCL) of 10 milligrams per liter. Results of the analyses of water-quality samples collected during 1980-89 from 230 shallow wells in the outcrop areas of the Kirkwood-Cohansey and Potomac-Raritan-Magothy aquifer systems were used to evaluate the regional effects of land use on shallow-ground-water quality. Results of statistical analysis indicate that concentrations of nitrate in shallow ground water are significantly different (p= 0.001) in agricultural areas than in undeveloped areas in both aquifer systems. Concentrations of nitrate nitrogen exceeded the MCL in water from more than 33 percent of the 60 shallow wells in agricultural areas. Concentrations of hitrate in water from shallow wells in agricultural areas increased as the percentage of agricultural land within an 800-meter-radius buffer zone of the wellhead increased (r= 0.81). Concentrations ofhitrate in water from domestic wells in agricultural areas were similar (p= 0.23) to those concentrations in water from irrigation wells. These results indicate that most of the nitrate in water from domestic wells in agricultural areas results from agricultural practices rather than other sources, such as septic systems. Water-quality samples collected from 12 shallow domestic wells in agricultural areas screened in the outcrop areas of

  5. Wavelet-transform-based power management of hybrid vehicles with multiple on-board energy sources including fuel cell, battery and ultracapacitor

    NASA Astrophysics Data System (ADS)

    Zhang, Xi; Mi, Chris Chunting; Masrur, Abul; Daniszewski, David

    A wavelet-transform-based strategy is proposed for the power management of hybrid electric vehicles (HEV) with multiple on-board energy sources and energy storage systems including a battery, a fuel cell, and an ultra-capacitor. The proposed wavelet-transform algorithm is capable of identifying the high-frequency transient and real time power demand of the HEV, and allocating power components with different frequency contents to corresponding sources to achieve an optimal power management control algorithm. By using the wavelet decomposition algorithm, a proper combination can be achieved with a properly sized ultra-capacitor dealing with the chaotic high-frequency components of the total power demand, while the fuel cell and battery deal with the low and medium frequency power demand. Thus the system efficiency and life expectancy can be greatly extended. Simulation and experimental results validated the effectiveness of wavelet-transform-based power management algorithm.

  6. Quantifying the dominant sources of sediment in a drained lowland agricultural catchment: The application of a thorium-based particle size correction in sediment fingerprinting

    NASA Astrophysics Data System (ADS)

    Foucher, Anthony; Laceby, Patrick J.; Salvador-Blanes, Sébastien; Evrard, Olivier; Le Gall, Marion; Lefèvre, Irène; Cerdan, Olivier; Rajkumar, Vignesh; Desmet, Marc

    2015-12-01

    Soil erosion is one of the main factors influencing land degradation and water quality at the global scale. Identifying the main sediment sources is therefore essential for the implementation of appropriate soil erosion mitigation measures. Accordingly, caesium-137 (137Cs) concentrations were used to determine the relative contribution of surface and subsurface erosion sources in a lowland drained catchment in France. As 137Cs concentrations are often dependent on particle size, specific surface area (SSA) and novel thorium (Th) based particle size corrections were applied. Surface and subsurface samples were collected to characterize the radionuclide properties of potential sources. Sediment samples were collected during one hydrological year and a sediment core was sampled to represent sediment accumulated over a longer temporal period. Additionally, sediment from tile drains was sampled to determine the radionuclide properties of sediment exported from the drainage network. A distribution modelling approach was used to quantify the relative sediment contributions from surface and subsurface sources. The results highlight a substantial enrichment in fine particles and associated 137Cs concentrations between the sources and the sediment. The application of both correction factors reduced this difference, with the Th correction providing a more accurate comparison of source and sediment samples than the SSA correction. Modelling results clearly indicate the dominance of surface sources during the flood events and in the sediment core. Sediment exported from the drainage network was modelled to originate predominantly from surface sources. This study demonstrates the potential of Th to correct for 137Cs particle size enrichment. More importantly, this research indicates that drainage networks may significantly increase the connectivity of surface sources to stream networks. Managing sediment transferred through drainage networks may reduce the deleterious effects of

  7. Dynamics and sources of reduced sulfur, humic substances and dissolved organic carbon in a temperate river system affected by agricultural practices.

    PubMed

    Marie, Lauriane; Pernet-Coudrier, Benoît; Waeles, Matthieu; Gabon, Marine; Riso, Ricardo

    2015-12-15

    Although reduced organic sulfur substances (RSS) as well as humic substances (HS) are widely suspected to play a role in, for example, metal speciation or used as a model of dissolved organic carbon (DOC) in laboratory studies, reports of their quantification in natural waters are scarce. We have examined the dynamics and sources of reduced sulfur, HS and DOC over an annual cycle in a river system affected by agricultural practices. The new differential pulse cathodic stripping voltammetry was successfully applied to measure glutathione-like compounds (GSHs), thioacetamide-like compounds (TAs) and the liquid chromatography coupled to organic detector to analyze HS and DOC at high frequency in the Penzé River (NW France). The streamflow-concentration patterns, principal components analysis and flux analysis allowed discrimination of the source of each organic compound type. Surprisingly, the two RSS and HS detected in all samples, displayed different behavior. As previously shown, manuring practice is the main source of DOC and HS in this watershed where agricultural activity is predominant. The HS were then transferred to the river systems via runoff, particularly during the spring and autumn floods, which are responsible of >60% of the annual flux. TAs had a clear groundwater source and may be formed underground, whereas GSHs displayed two sources: one aquagenic in spring and summer probably linked to the primary productivity and a second, which may be related to bacterial degradation. High sampling frequency allowed a more accurate assessment of the flux values which were 280 tC y(-1) for DOC representing 20 kg C ha(-1) y(-1). HS, TAs and GSHs fluxes represented 60, 13, and 4% of the total annual DOC export, respectively.

  8. Dynamics and sources of reduced sulfur, humic substances and dissolved organic carbon in a temperate river system affected by agricultural practices.

    PubMed

    Marie, Lauriane; Pernet-Coudrier, Benoît; Waeles, Matthieu; Gabon, Marine; Riso, Ricardo

    2015-12-15

    Although reduced organic sulfur substances (RSS) as well as humic substances (HS) are widely suspected to play a role in, for example, metal speciation or used as a model of dissolved organic carbon (DOC) in laboratory studies, reports of their quantification in natural waters are scarce. We have examined the dynamics and sources of reduced sulfur, HS and DOC over an annual cycle in a river system affected by agricultural practices. The new differential pulse cathodic stripping voltammetry was successfully applied to measure glutathione-like compounds (GSHs), thioacetamide-like compounds (TAs) and the liquid chromatography coupled to organic detector to analyze HS and DOC at high frequency in the Penzé River (NW France). The streamflow-concentration patterns, principal components analysis and flux analysis allowed discrimination of the source of each organic compound type. Surprisingly, the two RSS and HS detected in all samples, displayed different behavior. As previously shown, manuring practice is the main source of DOC and HS in this watershed where agricultural activity is predominant. The HS were then transferred to the river systems via runoff, particularly during the spring and autumn floods, which are responsible of >60% of the annual flux. TAs had a clear groundwater source and may be formed underground, whereas GSHs displayed two sources: one aquagenic in spring and summer probably linked to the primary productivity and a second, which may be related to bacterial degradation. High sampling frequency allowed a more accurate assessment of the flux values which were 280 tC y(-1) for DOC representing 20 kg C ha(-1) y(-1). HS, TAs and GSHs fluxes represented 60, 13, and 4% of the total annual DOC export, respectively. PMID:26278374

  9. Comparative study on nutrient removal of agricultural non-point source pollution for three filter media filling schemes in eco-soil reactors.

    PubMed

    Du, Fuyi; Xie, Qingjie; Fang, Longxiang; Su, Hang

    2016-08-01

    Nutrients (nitrogen and phosphorus) from agricultural non-point source (NPS) pollution have been increasingly recognized as a major contributor to the deterioration of water quality in recent years. The purpose of this article is to investigate the discrepancies in interception of nutrients in agricultural NPS pollution for eco-soil reactors using different filling schemes. Parallel eco-soil reactors of laboratory scale were created and filled with filter media, such as grit, zeolite, limestone, and gravel. Three filling schemes were adopted: increasing-sized filling (I-filling), decreasing-sized filling (D-filling), and blend-sized filling (B-filling). The systems were intermittent operations via simulated rainstorm runoff. The nutrient removal efficiency, biomass accumulation and vertical dissolved oxygen (DO) distribution were defined to assess the performance of eco-soil. The results showed that B-filling reactor presented an ideal DO for partial nitrification-denitrification across the eco-soil, and B-filling was the most stable in the change of bio-film accumulation trends with depth in the three fillings. Simultaneous and highest removals of NH4(+)-N (57.74-70.52%), total nitrogen (43.69-54.50%), and total phosphorus (42.50-55.00%) were obtained in the B-filling, demonstrating the efficiency of the blend filling schemes of eco-soil for oxygen transfer and biomass accumulation to cope with agricultural NPS pollution. PMID:27441855

  10. Geologic sources and concentrations of selenium in the West-Central Denver Basin, including the Toll Gate Creek watershed, Aurora, Colorado, 2003-2007

    USGS Publications Warehouse

    Paschke, Suzanne S.; Walton-Day, Katie; Beck, Jennifer A.; Webbers, Ank; Dupree, Jean A.

    2014-01-01

    Toll Gate Creek, in the west-central part of the Denver Basin, is a perennial stream in which concentrations of dissolved selenium have consistently exceeded the Colorado aquatic-life standard of 4.6 micrograms per liter. Recent studies of selenium in Toll Gate Creek identified the Denver lignite zone of the non-marine Cretaceous to Tertiary-aged (Paleocene) Denver Formation underlying the watershed as the geologic source of dissolved selenium to shallow ground-water and surface water. Previous work led to this study by the U.S. Geological Survey, in cooperation with the City of Aurora Utilities Department, which investigated geologic sources of selenium and selenium concentrations in the watershed. This report documents the occurrence of selenium-bearing rocks and groundwater within the Cretaceous- to Tertiary-aged Denver Formation in the west-central part of the Denver Basin, including the Toll Gate Creek watershed. The report presents background information on geochemical processes controlling selenium concentrations in the aquatic environment and possible geologic sources of selenium; the hydrogeologic setting of the watershed; selenium results from groundwater-sampling programs; and chemical analyses of solids samples as evidence that weathering of the Denver Formation is a geologic source of selenium to groundwater and surface water in the west-central part of the Denver Basin, including Toll Gate Creek. Analyses of water samples collected from 61 water-table wells in 2003 and from 19 water-table wells in 2007 indicate dissolved selenium concentrations in groundwater in the west-central Denver Basin frequently exceeded the Colorado aquatic-life standard and in some locations exceeded the primary drinking-water standard of 50 micrograms per liter. The greatest selenium concentrations were associated with oxidized groundwater samples from wells completed in bedrock materials. Selenium analysis of geologic core samples indicates that total selenium

  11. Identifying sediment sources in a drained lowland agricultural catchment: the application of a novel thorium-based particle size correction in sediment fingerprinting

    NASA Astrophysics Data System (ADS)

    Laceby, J. P.; Le Gall, M.; Foucher, A.; Salvador-Blanes, S.; Evrard, O.; Lefèvre, I.; Cerdan, O.; Desmet, M.

    2015-12-01

    Soil erosion is one of the main processes influencing land and water degradation at the global scale. Identifying the main sediment sources is therefore essential for effective soil erosion management. Accordingly, caesium-137 (137Cs) concentrations were used to quantify the relative contribution of surface and subsurface erosion sources in a lowland drained catchment in France. As 137Cs concentrations are often dependent on particle size, specific surface area (SSA) and novel Thorium (Th) based particle size corrections were applied. Surface and subsurface samples were collected to characterize the radionuclide properties of potential sources. Sediment samples were collected during one hydrological year and a sediment core was sampled to represent sediment accumulated over a longer temporal period. Additionally, sediment from tile drains was sampled to determine the radionuclide properties of sediment exported from the drainage network. The results highlight a substantial enrichment in fine particles and associated 137Cs concentrations between the sources and the sediment. The application of both correction factors reduced this difference, with the Th correction providing a more accurate comparison of source and sediment samples than the SSA correction. Modelling results clearly indicate the dominance of surface sources during the flood events and in the sediment core. Sediment exported from the drainage network was modelled to originate predominantly from surface sources. This study demonstrates the potential of Th to correct for 137Cs particle size enrichment. More importantly, this research indicates that drainage networks may significantly increase the connectivity of surface sources to stream networks. Managing sediment transferred through drainage networks may reduce the deleterious effects of suspended sediment loads on riverine systems in similar lowland drained agricultural catchments.

  12. Urban Agricultural Education.

    ERIC Educational Resources Information Center

    Corbellini, Margaret

    1991-01-01

    John Bourne High School in Queens, New York, offers an agricultural program enrolling more than 400 students. The curriculum includes agricultural career exploration, plant and animal science, summer land laboratories, and a special education component. (SK)

  13. Agricultural lung diseases.

    PubMed Central

    Kirkhorn, S R; Garry, V F

    2000-01-01

    Agriculture is considered one of the most hazardous occupations. Organic dusts and toxic gases constitute some of the most common and potentially disabling occupational and environmental hazards. The changing patterns of agriculture have paradoxically contributed to both improved working conditions and increased exposure to respiratory hazards. Animal confinement operations with increasing animal density, particularly swine confinement, have contributed significantly to increased intensity and duration of exposure to indoor air toxins. Ongoing research has implicated bacterial endotoxins, fungal spores, and the inherent toxicity of grain dusts as causes of upper and lower airway inflammation and as immunologic agents in both grain and animal production. Animal confinement gases, particularly ammonia and hydrogen sulfide, have been implicated as additional sources of respiratory irritants. It has become evident that a significant percentage of agricultural workers have clinical symptoms associated with long-term exposure to organic dusts and animal confinement gases. Respiratory diseases and syndromes, including hypersensitivity pneumonitis, organic dust toxic syndrome, chronic bronchitis, mucous membrane inflammation syndrome, and asthmalike syndrome, result from ongoing acute and chronic exposures. In this review we focus upon the emerging respiratory health issues in a changing agricultural economic and technologic environment. Environmental and occupational hazards and exposures will be emphasized rather than clinical diagnosis and treatment. Methods of prevention, from both engineering controls and personal respiratory perspectives, are also addressed. PMID:10931789

  14. Identification of groundwater contamination sources of nitrate and sulfate in shallow alluvial aquifers using a dual-isotope approach in an agricultural area

    NASA Astrophysics Data System (ADS)

    Kaown, D.; Koh, D.; Mayer, B.; Hyun, Y.; Bae, G.; Lee, K.

    2007-12-01

    The elevated level of nitrate in groundwater is a serious problem in Korean agricultural areas. Yupori, a small agricultural area in Chuncheon (Korea), shows a rising level of NO3-N and displays multiple NO3-N sources from non-point and point sources in shallow aquifer groundwater. Numerous vegetable fields are located in the western part of the study area and fruit orchards dominate the landscape with only few vegetable fields in the eastern part of the study area. The source identification of groundwater contamination from overburden agricultural area was undertaken by analyzing hydrochemical data and stable isotopic compositions of dissolved nitrate and sulfate (¥ä15N-NO3-, ¥ä18O-NO3-, ¥ä34S-SO42-, and ¥ä18O-SO42-). The measurements of ¥ä15N- NO3- are in the range of 7.1 to 14.4¢¶ and the values of ¥ä18O-NO3- are in the range of -1.8 to 6.5¢¶. High ¥ä15N-NO3- values shown at low concentrations of nitrate in the eastern Yupori are characteristics of manure- derived nitrate and organic soil. The values of ¥ä34S-SO4-2 ranged from 2.9 to 9.9¢¶ and ¥ä18O-SO42- ranged from 2.5 to 4.7¢¶. At high concentrations of SO42- in the western Yupori, the value of ¥ä34S-SO42- are low around 3-4¢¶. The value of ¥ä34S-SO42- increased with decreasing SO42- concentration in the eastern Yupori. Groundwater quality and stable isotopic compositions of dissolved nitrate and sulfate seem to be significantly affected by agricultural land use pattern of the study site.

  15. Levels and sources of volatile organic compounds including carbonyls in indoor air of homes of Puertollano, the most industrialized city in central Iberian Peninsula. Estimation of health risk.

    PubMed

    Villanueva, Florentina; Tapia, Araceli; Amo-Salas, Mariano; Notario, Alberto; Cabañas, Beatriz; Martínez, Ernesto

    2015-08-01

    Twenty nine organic air pollutants including carbonyl compounds, alkanes, aromatic hydrocarbons and terpenes were measured in the indoor environment of different houses together with the corresponding outdoor measurements in Puertollano, the most industrialized city in central Iberian Peninsula. VOCs were sampled during 8 weeks using Radiello(®) passive samplers, and a questionnaire on potential VOCs sources was filled out by the occupants. The results show that formaldehyde and hexanal was the most abundant VOCs measured in indoor air, with a median concentration of 55.5 and 46.4μgm(-3), respectively followed by butanal (29.1μgm(-3)), acetone (28.4μgm(-3)) and acetaldehyde (21.4μgm(-3)). After carbonyls, n-dodecane (13.1μgm(-3)) and terpenes (α-pinene, 13.4μgm(-3) and limonene, 13.4μgm(-3)) were the compounds with higher median concentrations. The indoor/outdoor (I/O) ratios demonstrated that sources in the indoor environment are prevailing for most of the investigated VOCs especially for limonene, α-pinene, hexanal, formaldehyde, pentanal, acetaldehyde, o-xylene, n-dodecane and acetone with I/O ratio >6. Multiple linear regressions were applied to investigate the indoor VOC determinants and Spearman correlation coefficients were used to establish common sources between VOCs. Finally, the lifetime cancer risk associated to formaldehyde, acetaldehyde and benzene exposure was estimated and they varied from 7.8×10(-5) to 4.1×10(-4) for formaldehyde, from 8.6×10(-6) to 3.5×10(-5) for acetaldehyde and from 2.0×10(-6) to 1.5×10(-5) for benzene. For formaldehyde, the attributed risk in most sampled homes was two orders of magnitude higher than the one (10(-6)) proposed as acceptable by risk management bodies.

  16. Simultaneous Determination of Thermal Conductivity and Thermal Diffusivity of Food and Agricultural Materials Using a Transient Plane-Source Method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thermal conductivity and thermal diffusivity are two important physical properties essential for designing any food engineering processes. Recently a new transient plane-source method was developed to measure a variety of materials, but its application in foods has not been documented. Therefore, ...

  17. Comparison of Online Agricultural Information Services.

    ERIC Educational Resources Information Center

    Reneau, Fred; Patterson, Richard

    1984-01-01

    Outlines major online agricultural information services--agricultural databases, databases with agricultural services, educational databases in agriculture--noting services provided, access to the database, and costs. Benefits of online agricultural database sources (availability of agricultural marketing, weather, commodity prices, management…

  18. Identifying sources of groundwater nitrate contamination in a large alluvial groundwater basin with highly diversified intensive agricultural production.

    PubMed

    Lockhart, K M; King, A M; Harter, T

    2013-08-01

    Groundwater quality is a concern in alluvial aquifers underlying agricultural areas worldwide. Nitrate from land applied fertilizers or from animal waste can leach to groundwater and contaminate drinking water resources. The San Joaquin Valley, California, is an example of an agricultural landscape with a large diversity of field, vegetable, tree, nut, and citrus crops, but also confined animal feeding operations (CAFOs, here mostly dairies) that generate, store, and land apply large amounts of liquid manure. As in other such regions around the world, the rural population in the San Joaquin Valley relies almost exclusively on shallow domestic wells (≤150 m deep), of which many have been affected by nitrate. Variability in crops, soil type, and depth to groundwater contribute to large variability in nitrate occurrence across the underlying aquifer system. The role of these factors in controlling groundwater nitrate contamination levels is examined. Two hundred domestic wells were sampled in two sub-regions of the San Joaquin Valley, Stanislaus and Merced (Stan/Mer) and Tulare and Kings (Tul/Kings) Counties. Forty six percent of well water samples in Tul/Kings and 42% of well water samples in Stan/Mer exceeded the MCL for nitrate (10mg/L NO3-N). For statistical analysis of nitrate contamination, 78 crop and landuse types were considered by grouping them into ten categories (CAFO, citrus, deciduous fruits and nuts, field crops, forage, native, pasture, truck crops, urban, and vineyards). Vadose zone thickness, soil type, well construction information, well proximity to dairies, and dominant landuse near the well were considered. In the Stan/Mer area, elevated nitrate levels in domestic wells most strongly correlate with the combination of very shallow (≤21 m) water table and the presence of either CAFO derived animal waste applications or deciduous fruit and nut crops (synthetic fertilizer applications). In Tulare County, statistical data indicate that elevated

  19. Identifying sources of groundwater nitrate contamination in a large alluvial groundwater basin with highly diversified intensive agricultural production

    NASA Astrophysics Data System (ADS)

    Lockhart, K. M.; King, A. M.; Harter, T.

    2013-08-01

    Groundwater quality is a concern in alluvial aquifers underlying agricultural areas worldwide. Nitrate from land applied fertilizers or from animal waste can leach to groundwater and contaminate drinking water resources. The San Joaquin Valley, California, is an example of an agricultural landscape with a large diversity of field, vegetable, tree, nut, and citrus crops, but also confined animal feeding operations (CAFOs, here mostly dairies) that generate, store, and land apply large amounts of liquid manure. As in other such regions around the world, the rural population in the San Joaquin Valley relies almost exclusively on shallow domestic wells (≤ 150 m deep), of which many have been affected by nitrate. Variability in crops, soil type, and depth to groundwater contribute to large variability in nitrate occurrence across the underlying aquifer system. The role of these factors in controlling groundwater nitrate contamination levels is examined. Two hundred domestic wells were sampled in two sub-regions of the San Joaquin Valley, Stanislaus and Merced (Stan/Mer) and Tulare and Kings (Tul/Kings) Counties. Forty six percent of well water samples in Tul/Kings and 42% of well water samples in Stan/Mer exceeded the MCL for nitrate (10 mg/L NO3-N). For statistical analysis of nitrate contamination, 78 crop and landuse types were considered by grouping them into ten categories (CAFO, citrus, deciduous fruits and nuts, field crops, forage, native, pasture, truck crops, urban, and vineyards). Vadose zone thickness, soil type, well construction information, well proximity to dairies, and dominant landuse near the well were considered. In the Stan/Mer area, elevated nitrate levels in domestic wells most strongly correlate with the combination of very shallow (≤ 21 m) water table and the presence of either CAFO derived animal waste applications or deciduous fruit and nut crops (synthetic fertilizer applications). In Tulare County, statistical data indicate that elevated

  20. Identifying sources of groundwater nitrate contamination in a large alluvial groundwater basin with highly diversified intensive agricultural production.

    PubMed

    Lockhart, K M; King, A M; Harter, T

    2013-08-01

    Groundwater quality is a concern in alluvial aquifers underlying agricultural areas worldwide. Nitrate from land applied fertilizers or from animal waste can leach to groundwater and contaminate drinking water resources. The San Joaquin Valley, California, is an example of an agricultural landscape with a large diversity of field, vegetable, tree, nut, and citrus crops, but also confined animal feeding operations (CAFOs, here mostly dairies) that generate, store, and land apply large amounts of liquid manure. As in other such regions around the world, the rural population in the San Joaquin Valley relies almost exclusively on shallow domestic wells (≤150 m deep), of which many have been affected by nitrate. Variability in crops, soil type, and depth to groundwater contribute to large variability in nitrate occurrence across the underlying aquifer system. The role of these factors in controlling groundwater nitrate contamination levels is examined. Two hundred domestic wells were sampled in two sub-regions of the San Joaquin Valley, Stanislaus and Merced (Stan/Mer) and Tulare and Kings (Tul/Kings) Counties. Forty six percent of well water samples in Tul/Kings and 42% of well water samples in Stan/Mer exceeded the MCL for nitrate (10mg/L NO3-N). For statistical analysis of nitrate contamination, 78 crop and landuse types were considered by grouping them into ten categories (CAFO, citrus, deciduous fruits and nuts, field crops, forage, native, pasture, truck crops, urban, and vineyards). Vadose zone thickness, soil type, well construction information, well proximity to dairies, and dominant landuse near the well were considered. In the Stan/Mer area, elevated nitrate levels in domestic wells most strongly correlate with the combination of very shallow (≤21 m) water table and the presence of either CAFO derived animal waste applications or deciduous fruit and nut crops (synthetic fertilizer applications). In Tulare County, statistical data indicate that elevated

  1. Agricultural nonpoint source pollution and economic incentive policies. Issues in the reauthorization of the Clean Water Act. Staff report

    SciTech Connect

    Malik, A.S.; Larson, B.A.; Ribaudo, M.

    1992-11-01

    The limited success of command-and-control policies for reducing nonpoint source (NPS) water pollution mandated under the Federal Water Pollution Control Act (FWPCA) has prompted increased interest in economic incentive policies as an alternative control mechanism. No single policy, however, is likely to be effective in reducing all NPS pollution. Economic incentives may be effective in some cases, command-and-control practices in others.

  2. Coherence among different microbial source tracking markers in a small agricultural stream with or without livestock exclusion practices.

    PubMed

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A; Gannon, Victor; Jokinen, Cassandra C; Jones, Tineke H; Marti, Romain; Neumann, Norman F; Ruecker, Norma J; Sunohara, Mark; Topp, Edward; Lapen, David R

    2013-10-01

    Over 1,400 water samples were collected biweekly over 6 years from an intermittent stream protected and unprotected from pasturing cattle. The samples were monitored for host-specific Bacteroidales markers, Cryptosporidium species/genotypes, viruses and coliphages associated with humans or animals, and bacterial zoonotic pathogens. Ruminant Bacteroidales markers did not increase within the restricted cattle access reach of the stream, whereas the ruminant Bacteroidales marker increased significantly in the unrestricted cattle access reach. Human Bacteroidales markers significantly increased downstream of homes where septic issues were documented. Wildlife Bacteroidales markers were detected downstream of the cattle exclusion practice where stream and riparian habitat was protected, but detections decreased after the unrestricted pasture, where the stream and riparian zone was unprotected from livestock. Detection of a large number of human viruses was shown to increase downstream of homes, and similar trends were observed for the human Bacteroidales marker. There was considerable interplay among biomarkers with stream flow, season, and the cattle exclusion practices. There were no to very weak associations with Bacteroidales markers and bacterial, viral, and parasitic pathogens. Overall, discrete sample-by-sample coherence among the different microbial source tracking markers that expressed a similar microbial source was minimal, but spatial trends were physically meaningful in terms of land use (e.g., beneficial management practice) effects on sources of fecal pollution.

  3. Coherence among Different Microbial Source Tracking Markers in a Small Agricultural Stream with or without Livestock Exclusion Practices

    PubMed Central

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A.; Gannon, Victor; Jokinen, Cassandra C.; Jones, Tineke H.; Marti, Romain; Neumann, Norman F.; Ruecker, Norma J.; Sunohara, Mark; Topp, Edward

    2013-01-01

    Over 1,400 water samples were collected biweekly over 6 years from an intermittent stream protected and unprotected from pasturing cattle. The samples were monitored for host-specific Bacteroidales markers, Cryptosporidium species/genotypes, viruses and coliphages associated with humans or animals, and bacterial zoonotic pathogens. Ruminant Bacteroidales markers did not increase within the restricted cattle access reach of the stream, whereas the ruminant Bacteroidales marker increased significantly in the unrestricted cattle access reach. Human Bacteroidales markers significantly increased downstream of homes where septic issues were documented. Wildlife Bacteroidales markers were detected downstream of the cattle exclusion practice where stream and riparian habitat was protected, but detections decreased after the unrestricted pasture, where the stream and riparian zone was unprotected from livestock. Detection of a large number of human viruses was shown to increase downstream of homes, and similar trends were observed for the human Bacteroidales marker. There was considerable interplay among biomarkers with stream flow, season, and the cattle exclusion practices. There were no to very weak associations with Bacteroidales markers and bacterial, viral, and parasitic pathogens. Overall, discrete sample-by-sample coherence among the different microbial source tracking markers that expressed a similar microbial source was minimal, but spatial trends were physically meaningful in terms of land use (e.g., beneficial management practice) effects on sources of fecal pollution. PMID:23913430

  4. Agriculture, Environmental Education Guide.

    ERIC Educational Resources Information Center

    Project I-C-E, Green Bay, WI.

    This agriculture guide, for use at the secondary level, is one of a series of guides, K-12, which were developed by teachers to help introduce environmental education into the total curriculum. Environmental problems are present in every community where agriculture education is offered, and therefore many agriculture teachers have included some…

  5. Levels and sources of volatile organic compounds including carbonyls in indoor air of homes of Puertollano, the most industrialized city in central Iberian Peninsula. Estimation of health risk.

    PubMed

    Villanueva, Florentina; Tapia, Araceli; Amo-Salas, Mariano; Notario, Alberto; Cabañas, Beatriz; Martínez, Ernesto

    2015-08-01

    Twenty nine organic air pollutants including carbonyl compounds, alkanes, aromatic hydrocarbons and terpenes were measured in the indoor environment of different houses together with the corresponding outdoor measurements in Puertollano, the most industrialized city in central Iberian Peninsula. VOCs were sampled during 8 weeks using Radiello(®) passive samplers, and a questionnaire on potential VOCs sources was filled out by the occupants. The results show that formaldehyde and hexanal was the most abundant VOCs measured in indoor air, with a median concentration of 55.5 and 46.4μgm(-3), respectively followed by butanal (29.1μgm(-3)), acetone (28.4μgm(-3)) and acetaldehyde (21.4μgm(-3)). After carbonyls, n-dodecane (13.1μgm(-3)) and terpenes (α-pinene, 13.4μgm(-3) and limonene, 13.4μgm(-3)) were the compounds with higher median concentrations. The indoor/outdoor (I/O) ratios demonstrated that sources in the indoor environment are prevailing for most of the investigated VOCs especially for limonene, α-pinene, hexanal, formaldehyde, pentanal, acetaldehyde, o-xylene, n-dodecane and acetone with I/O ratio >6. Multiple linear regressions were applied to investigate the indoor VOC determinants and Spearman correlation coefficients were used to establish common sources between VOCs. Finally, the lifetime cancer risk associated to formaldehyde, acetaldehyde and benzene exposure was estimated and they varied from 7.8×10(-5) to 4.1×10(-4) for formaldehyde, from 8.6×10(-6) to 3.5×10(-5) for acetaldehyde and from 2.0×10(-6) to 1.5×10(-5) for benzene. For formaldehyde, the attributed risk in most sampled homes was two orders of magnitude higher than the one (10(-6)) proposed as acceptable by risk management bodies. PMID:26025206

  6. Total and infectious Cryptosporidium oocyst and total Giardia cyst concentrations from distinct agricultural and urban contamination sources in Eastern Canada.

    PubMed

    Lalancette, Cindy; Généreux, Mylène; Mailly, Jacinthe; Servais, Pierre; Côté, Caroline; Michaud, Aubert; Di Giovanni, George D; Prévost, Michèle

    2012-03-01

    Cryptosporidium and Giardia (oo)cyst concentrations are frequently used for assessing drinking water safety. The widely used USEPA Method 1623 provides total counts of (oo)cysts, but may not be accurate for human health risk characterization, since it does not provide infectivity information. The total counts and infectious fraction of Cryptosporidium oocysts and the total counts of Giardia cysts were assessed in major fecal pollution sources. Fresh calf and cow feces, their manure, and the discharge point were sampled in a small rural sub-watershed (n = 20, 21, 10, 10). Median concentrations for total (oo)cysts were higher in calves (333 oocysts g(-1); 111 cysts g(-1)) than in cows (52 oocysts g(-1); 7 cysts g(-1)). Infectious oocysts were found in 17 (7%) of the samples and none were found in manure or at the discharge point. Urban sources were sampled in the influent and effluent (n = 19, 18) of two wastewater treatment plants. Peak concentrations were 533 oocysts L(-1) and 9,010 cysts L(-1) for influents and 89 oocysts L(-1) and 472 cysts L(-1) for effluents. Infectious oocyst fractions varied from below the detection limit to 7-22% in the effluent and influent respectively. These infectious fractions are significantly lower than those currently used for quantitative microbial risk assessment estimates. PMID:22361710

  7. Response of Polish rivers (Vistula, Oder) to reduced pressure from point sources and agriculture during the transition period (1988-2008)

    NASA Astrophysics Data System (ADS)

    Pastuszak, Marianna; Stålnacke, Per; Pawlikowski, Krzysztof; Witek, Zbigniew

    2012-06-01

    The Vistula and Oder Rivers, two out of the seven largest rivers in the Baltic drainage basin, were responsible for 25% of total riverine nitrogen (TN) and 37% of total riverine phosphorus (TP) input to the Baltic Sea in 2000. The aim of this paper is to evaluate the response of these two rivers to changes that took place in Polish economy during the transition period (1988-2008). The economic changes encompassed: construction of nearly 900 waste water treatment plants in 1999-2008, modernization or closure of obsolete factories, economizing in water consumption, closure or change of ownership of State-owned farms, a drop in fertilizer application, and a decline in livestock stocking. More intensive agriculture and higher point source emissions in the Oder than in the Vistula basin resulted in higher concentrations of TN, nitrate (NO3-N), and TP in the Oder waters in the entire period of our studies. In both rivers, nutrient concentrations and loads showed significant declining trends in the period 1988-2008. TN loads decreased by ca. 20% and 25% in the Vistula and Oder; TP loads dropped by ca. 15% and 65% in the Vistula and Oder. The reduction in phosphorus loads was particularly pronounced in the Oder basin, which was characterized by efficient management systems aiming at mitigation of nutrient emission from the point sources and greater extent of structural changes in agricultural sector during the transition period. The trends in riverine loads are discussed in the paper in relation to socio-economical changes during the transition period, and with respect to physiographic features.

  8. Integrating GRACE and multi-source data sets to quantify the seasonal groundwater depletion in mega agricultural regions

    NASA Astrophysics Data System (ADS)

    Tang, Y.; Wang, D.; Zhu, T.; Ringler, C.; Sun, A. Y.

    2015-12-01

    It is challenging to quantify the groundwater depletion in the mega basins owing to the huge spatial scale and the intensive anthrophonic activities (e.g. dams and reservoirs). Recently, the satellite Gravity Recovery and Climate Experiment (GRACE) data provides an opportunity to monitor large-scale groundwater depletion. However, the data is only available after 2002, limiting the understanding of inter-annual variability of seasonal groundwater depletion. In this study, a simple model with two parameters is developed, based on the seasonal Budyko framework for quantifying the seasonal groundwater depletion. The model is applied to the Indus and Ganges River basin in South Asia and the High Plain/Ogallala aquifer in United States. The parameters of the model are estimated by integrating GRACE and other multi-source data sets. Total water storage changes before 2003 are reconstructed based on the developed model with available data of evaporation, precipitation, and potential evaporation.

  9. Streamflow and water-quality conditions including geologic sources and processes affecting selenium loading in the Toll Gate Creek watershed, Aurora, Arapahoe County, Colorado, 2007

    USGS Publications Warehouse

    Paschke, Suzanne S.; Runkel, Robert L.; Walton-Day, Katherine; Kimball, Briant A.; Schaffrath, Keelin R.

    2013-01-01

    discrete groundwater inflow supports streamflow during low-flow conditions along the entire 18-kilometer stream reach. Concentrations of dissolved selenium within all subreaches of Toll Gate Creek exceeded the Colorado aquatic-life standard of 4.6 micrograms per liter in 2007. Concentrations of selenium in the upper portion of the Toll Gate Headwaters subreach (TGH) remained close to the aquatic-life standard at about 5 micrograms per liter. Downstream from a concrete-lined channel section, inflows with selenium concentrations greater than the stream contribute selenium load to surface water. However, stream selenium concentrations were less than 20 micrograms per liter all along Toll Gate Creek. Concentrations of selenium in groundwater were in general substantially greater than the Colorado aquatic-life standard of 4.6 micrograms per liter and at some locations were greater than the U.S. Environmental Protection Agency primary drinking-water standard for selenium of 50 micrograms per liter. The distribution of selenium concentrations in groundwater, springs, and the 11 inflows with the greatest selenium concentrations indicates that shallow groundwater in surficial materials and the Denver Formation bedrock is a source of selenium loading to Toll Gate Creek and that selenium loading is distributed along the entire length of the study reach downstream from the concrete-lined channel. Water-quality and solids-sampling results from this study indicate weathering processes release water-soluble selenium from the underlying Denver Formation claystone bedrock with subsequent cycling of selenium in the aquatic environment of Toll Gate Creek. Exposure of the Denver Formation selenium-bearing bedrock to oxidizing atmospheric conditions, surface water, and groundwater, oxidizes selenide, held as a trace element in pyrite or in complexes with organic matter, to selenite and selenate. Secondary weathering products including iron oxides and selenium-bearing salts have accumulated in

  10. Composition, sources, and potential toxicology of polycyclic aromatic hydrocarbons (PAHs) in agricultural soils in Liaoning, People's Republic of China.

    PubMed

    Cao, Xiu Feng; Liu, Miao; Song, Yu Fang; Ackland, M Leigh

    2013-03-01

    Surface soil (0-20 cm) samples (n = 143) were collected from vegetable, maize, and paddy farmland used for commercial crops in Liaoning, China. Sixteen priority polycyclic aromatic hydrocarbons (PAHs) listed in US Environmental Protection Agency were analyzed by high-performance liquid chromatography using a fluorescence detector. The soil concentrations of the 16 PAH ranged from 50 to 3,309 ng/g with a mean of 388 ng/g. The highest concentration of total PAHs found in soil of the vegetable farmland was 448 ng/g in average, followed by maize and paddy with total PAHs of 391 and 331 ng/g, respectively. Generally, the low molecular weight PAHs were more predominant than the high molecular weight PAHs in most of the soils. The evaluation of soil PAH contamination based on the Canadian criterion indicated that only naphthalene, phenanthrene, and pyrene were over the target values in several sampling sites. Isomer pair ratios and principal component analysis indicated that biomass and coal combustion were the main sources of PAHs in this area. And the average value of total B[a]Peq concentration in vegetable soils was higher than paddy and maize soils. We suggest that biomass burning should be abolished and commercial farming should be carried out far from the highways to ensure the safety of food products derived from commercial farming.

  11. Sources of atmospheric acidity in an agricultural-industrial region of São Paulo State, Brazil

    NASA Astrophysics Data System (ADS)

    Da Rocha, G. O.; Franco, A.; Allen, A. G.; Cardoso, A. A.

    2003-04-01

    Surface-based measurements of atmospheric formic acid (HCOOH), acetic acid (CH3COOH), sulfur dioxide (SO2), hydrogen chloride (HCl), and nitric acid (HNO3) were made in central São Paulo State, Brazil, between April 1999 and March 2000. Mean concentrations were 9.0 ppb (HCOOH), 1.3 ppb (CH3COOH), 4.9 ppb (SO2), 0.3 ppb (HCl), and 0.5 ppb (HNO3). Concentrations in sugar cane burning plumes were 1160-4230 ppb (HCOOH), 360-1750 ppb (CH3COOH), 10-630 ppb (SO2), 4-210 ppb (HCl), and 14-90 ppb (HNO3). Higher ambient concentrations of SO2, HCl and HNO3 were measured during the burning season (May-November). Concentrations of SO2 and HCl increased during the evening, and of HCOOH and CH3COOH were lowest in the morning, with peak levels in the afternoon. Ratios obtained between different species showed either nighttime maxima (SO2/HCOOH, SO2/CH3COOH, SO2/HNO3, CH3COOH/HNO3, SO2/HCl and HCOOH/HNO3), daytime maxima (HCOOH/HCl, CH3COOH/HCl and HNO3/HCl), or no clear trends (HCOOH/CH3COOH). Correlation analysis showed that SO2 and HCl were primary emissions from biomass burning and road transport; HCOOH, HNO3 and CH3COOH were products of photochemistry; HCOOH and CH3COOH were emitted directly during combustion as well as from biogenic sources. Biomass burning affected atmospheric acidity on a regional scale, while vehicular emissions had greater impact in urban and adjacent areas. Atmospheric ammonia levels were insufficient to neutralize atmospheric acidity, which was mainly removed by deposition to the surface.

  12. Characterizing Non-Point Source Pollution From Agricultural Landscape Using Remote Sensing And Gis - A Case Study From Sugarcreek Headwaters, Ohio, USA

    NASA Astrophysics Data System (ADS)

    Prasad, V. K.; Stinner, B.; McCartney, D.

    Ohio is typical among many mid west and eastern states in US that are experiencing elevated inputs of anthropogenic pollutants, especially from agricultural sources. In this study, we designed an integrated Remote sensing and GIS based approach to investigate and understand the role of landscape complexity affecting the spatial and temporal variation in pollutant loads in one of the most impaired headwater streams in Ohio. LANDSAT ETM+ data in conjunction with digital elevation model were used to compute the hydrological and watershed parameters, viz., wetness index, topographic index, soil loss, flow direction, flow accumulation, stream networks, stream orders, etc. These parameters were used in Geographic Information Systems framework along with step wise multiple linear regression to understand the spatial and temporal variation in pollutant loads. Among the different parameters, results suggested elevation range and upstream flow length as best predictors for nitrate, flow direction and upstream flow length for ammonia and slope and elevation range for phosphate loads. Methodology followed in the study and the results obtained suggest potential use of Remote sensing and GIS for characterizing non-point source pollution.

  13. Streamflow and water-quality conditions including geologic sources and processes affecting selenium loading in the Toll Gate Creek watershed, Aurora, Arapahoe County, Colorado, 2007

    USGS Publications Warehouse

    Paschke, Suzanne S.; Runkel, Robert L.; Walton-Day, Katherine; Kimball, Briant A.; Schaffrath, Keelin R.

    2013-01-01

    discrete groundwater inflow supports streamflow during low-flow conditions along the entire 18-kilometer stream reach. Concentrations of dissolved selenium within all subreaches of Toll Gate Creek exceeded the Colorado aquatic-life standard of 4.6 micrograms per liter in 2007. Concentrations of selenium in the upper portion of the Toll Gate Headwaters subreach (TGH) remained close to the aquatic-life standard at about 5 micrograms per liter. Downstream from a concrete-lined channel section, inflows with selenium concentrations greater than the stream contribute selenium load to surface water. However, stream selenium concentrations were less than 20 micrograms per liter all along Toll Gate Creek. Concentrations of selenium in groundwater were in general substantially greater than the Colorado aquatic-life standard of 4.6 micrograms per liter and at some locations were greater than the U.S. Environmental Protection Agency primary drinking-water standard for selenium of 50 micrograms per liter. The distribution of selenium concentrations in groundwater, springs, and the 11 inflows with the greatest selenium concentrations indicates that shallow groundwater in surficial materials and the Denver Formation bedrock is a source of selenium loading to Toll Gate Creek and that selenium loading is distributed along the entire length of the study reach downstream from the concrete-lined channel. Water-quality and solids-sampling results from this study indicate weathering processes release water-soluble selenium from the underlying Denver Formation claystone bedrock with subsequent cycling of selenium in the aquatic environment of Toll Gate Creek. Exposure of the Denver Formation selenium-bearing bedrock to oxidizing atmospheric conditions, surface water, and groundwater, oxidizes selenide, held as a trace element in pyrite or in complexes with organic matter, to selenite and selenate. Secondary weathering products including iron oxides and selenium-bearing salts have accumulated in

  14. Chemical characteristics, including stable-isotope ratios, of surface water and ground water from selected sources in and near East Fork Armells Creek basin, southeastern Montana, 1985

    USGS Publications Warehouse

    Ferreira, R.F.; Lambing, J.H.; Davis, R.E.

    1989-01-01

    Water samples were collected from 29 sites to provide synoptic chemical data, including stable-isotope ratios, for an area of active surface coal mining and to explore the effectiveness of using the data to chemically distinguish water from different aquifers. Surface-water samples were collected from one spring, four sites on East Armells Creek, one site on Stocker Creek, and two fly-ash ponds. Streamflows in East Fork Armells Creek ranged from no flow in several upstream reaches to 2.11 cu ft/sec downstream from Colstrip, Montana. Only one tributary, Stocker Creek, was observed to contribute surface flow in the study area. Groundwater samples were collected from wells completed in Quaternary alluvium or mine spoils, Rosebud overburden, Rosebud coal bed, McKay coal bed, and sub-McKay deposits of the Tongue River Member, Paleocene Fort Union Formation. Dissolved-solids concentrations, in mg/L, were 840 at the spring, 3,100 to 5,000 in the streams, 13,000 to 22,000 in the ash ponds, and 690 to 4 ,100 in the aquifers. With few exceptions, water from the sampled spring, streams, and wells had similar concentrations of major constituents and trace elements and similar stable-isotope ratios. Water from the fly-ash ponds had larger concentrations of dissolved solids, boron, and manganese and were isotopically more enriched in deuterium and oxygen-18 than water from other sources. Water from individual aquifers could not be distinguished by either ion-composition diagrams or statistical cluster analyses. (USGS)

  15. The PM2.5 chemical composition in an industrial zone included in a large urban settlement: main sources and local background.

    PubMed

    Squizzato, Stefania; Masiol, Mauro; Visin, Flavia; Canal, Andrea; Rampazzo, Giancarlo; Pavoni, Bruno

    2014-08-01

    Chemical analyses, receptor modeling and meteorological data were combined to determine the composition and sources of PM2.5 sampled daily in a large area in Italy characterized by a high number of heterogeneous industrial emissions and contiguous to a major urban center. The PM2.5 local background in the area, i.e. the common basic composition and concentrations of PM2.5, was determined. Factor analysis-multiple linear regression analysis (FA-MLRA) was used to identify and quantify the main PM sources. Groups of samples with similar source contributions were then sorted using cluster analysis. The potential source location and the influence of long range transport were investigated by using the conditional probability function (CPF) and the potential source contribution function (PSCF) respectively. On an annual basis, five sources of PM were found relevant. Industrial emissions accounted for 3% of PM mass, whereas the main contribution to PM was related to a combination of ammonium nitrate, combustion (54%) and road traffic (36%), mainly related to urban emissions. The PM2.5 background was estimated to account for 20 μg m(-3). It comprises contributions of 55% ammonium nitrate and combustion, 46% road traffic, 6% fossil fuel combustion and 3% industrial emissions. Source contributions are influenced by both local atmospheric circulation and regional transport.

  16. The PM2.5 chemical composition in an industrial zone included in a large urban settlement: main sources and local background.

    PubMed

    Squizzato, Stefania; Masiol, Mauro; Visin, Flavia; Canal, Andrea; Rampazzo, Giancarlo; Pavoni, Bruno

    2014-08-01

    Chemical analyses, receptor modeling and meteorological data were combined to determine the composition and sources of PM2.5 sampled daily in a large area in Italy characterized by a high number of heterogeneous industrial emissions and contiguous to a major urban center. The PM2.5 local background in the area, i.e. the common basic composition and concentrations of PM2.5, was determined. Factor analysis-multiple linear regression analysis (FA-MLRA) was used to identify and quantify the main PM sources. Groups of samples with similar source contributions were then sorted using cluster analysis. The potential source location and the influence of long range transport were investigated by using the conditional probability function (CPF) and the potential source contribution function (PSCF) respectively. On an annual basis, five sources of PM were found relevant. Industrial emissions accounted for 3% of PM mass, whereas the main contribution to PM was related to a combination of ammonium nitrate, combustion (54%) and road traffic (36%), mainly related to urban emissions. The PM2.5 background was estimated to account for 20 μg m(-3). It comprises contributions of 55% ammonium nitrate and combustion, 46% road traffic, 6% fossil fuel combustion and 3% industrial emissions. Source contributions are influenced by both local atmospheric circulation and regional transport. PMID:24912903

  17. Using U-series Isotopes To Determine Sources Of Pedogenic Carbonates: Comparison Of Natural And Agricultural Soils In The Semi-arid Southern New Mexico And Western Texas

    NASA Astrophysics Data System (ADS)

    Nyachoti, S. K.; Ma, L.; Borrok, D. M.; Jin, L.; Tweedie, C. E.

    2012-12-01

    Pedogenic carbonates commonly precipitate from infiltrating soil water in arid and semi-arid lands and are observed in soils of southern New Mexico and western Texas. These carbonates could form an impermeable layer in the soil horizons impairing water infiltration, thus affecting crop growth and yield. It is important to determine the source of C and Ca in these carbonates and to understand conditions favoring their formation, kinetics and precipitation rates. In this study, major elements and U-series isotopes in bulk calcic soils, and weak acid leachates and residues were measured from one irrigated alfalfa site in the Hueco basin near El Paso, TX and one natural shrubland site on the USDA Jornada experimental range in southern NM. The combined geochemical and isotopic results allow us to determine the formation ages of the carbonates; investigate the mobility of U, Th, and major elements in these soils; and infer for the effects of irrigation on carbonate formation in agricultural soils. Our results show distinctive U and Th isotope systems in the two soil profiles analyzed. For example, (234U/238U) ratios in the Jornada bulk soils decrease from ~1.01 to 0.96 towards the surface, consistent with a preferential loss of 234U over 238U during chemical weathering. At the Jornada site, (238U/232Th) ratios decrease while (230Th/238U) increase towards the surface, consistent with a general depletion of U and the immobility of Th in the natural soils. By contrast at the Alfalfa site, (234U/238U) ratios of bulk soils increase from ~ 0.97 to 1.02 towards the surface, suggesting an additional source of external uranium, most likely the irrigation water from Rio Grande which has a (234U/238U) ratio of ~ 1.5 near El Paso. The (238U/232Th) and (230Th/238U) ratios also imply leaching of U from shallower soils but precipitation in greater depths at Alfalfa site; suggests that partial dissolution and re-precipitation of younger carbonates occur. Calculated carbonate ages from U

  18. Support vector machine-an alternative to artificial neuron network for water quality forecasting in an agricultural nonpoint source polluted river?

    PubMed

    Liu, Mei; Lu, Jun

    2014-09-01

    Water quality forecasting in agricultural drainage river basins is difficult because of the complicated nonpoint source (NPS) pollution transport processes and river self-purification processes involved in highly nonlinear problems. Artificial neural network (ANN) and support vector model (SVM) were developed to predict total nitrogen (TN) and total phosphorus (TP) concentrations for any location of the river polluted by agricultural NPS pollution in eastern China. River flow, water temperature, flow travel time, rainfall, dissolved oxygen, and upstream TN or TP concentrations were selected as initial inputs of the two models. Monthly, bimonthly, and trimonthly datasets were selected to train the two models, respectively, and the same monthly dataset which had not been used for training was chosen to test the models in order to compare their generalization performance. Trial and error analysis and genetic algorisms (GA) were employed to optimize the parameters of ANN and SVM models, respectively. The results indicated that the proposed SVM models performed better generalization ability due to avoiding the occurrence of overtraining and optimizing fewer parameters based on structural risk minimization (SRM) principle. Furthermore, both TN and TP SVM models trained by trimonthly datasets achieved greater forecasting accuracy than corresponding ANN models. Thus, SVM models will be a powerful alternative method because it is an efficient and economic tool to accurately predict water quality with low risk. The sensitivity analyses of two models indicated that decreasing upstream input concentrations during the dry season and NPS emission along the reach during average or flood season should be an effective way to improve Changle River water quality. If the necessary water quality and hydrology data and even trimonthly data are available, the SVM methodology developed here can easily be applied to other NPS-polluted rivers.

  19. Biogenic Volatile Organic Compound (BVOC) emissions from agricultural crop species: is guttation a possible source for methanol emissions following light/dark transition ?

    NASA Astrophysics Data System (ADS)

    Mozaffar, Ahsan; Amelynck, Crist; Bachy, Aurélie; Digrado, Anthony; Delaplace, Pierre; du Jardin, Patrick; Fauconnier, Marie-Laure; Schoon, Niels; Aubinet, Marc; Heinesch, Bernard

    2015-04-01

    In the framework of the CROSTVOC (CROp STress VOC) project, the exchange of biogenic volatile organic compounds (BVOCs) between two important agricultural crop species, maize and winter wheat, and the atmosphere has recently been measured during an entire growing season by using the eddy covariance technique. Because of the co-variation of BVOC emission drivers in field conditions, laboratory studies were initiated in an environmental chamber in order to disentangle the responses of the emissions to variations of the individual environmental parameters (such as PPFD and temperature) and to diverse abiotic stress factors. Young plants were enclosed in transparent all-Teflon dynamic enclosures (cuvettes) through which BVOC-free and RH-controlled air was sent. BVOC enriched air was subsequently sampled from the plant cuvettes and an empty cuvette (background) and analyzed for BVOCs in a high sensitivity Proton Transfer Reaction Mass Spectrometer (hs-PTR-MS) and for CO2 in a LI-7000 non-dispersive IR gas analyzer. Emissions were monitored at constant temperature (25 °C) and at a stepwise varying PPFD pattern (0-650 µmol m-2 s-1). For maize plants, sudden light/dark transitions at the end of the photoperiod were accompanied by prompt and considerable increases in methanol (m/z 33) and water vapor (m/z 39) emissions. Moreover, guttation droplets appeared on the sides and the tips of the leaves within a few minutes after light/dark transition. Therefore the assumption has been raised that methanol is also coming out with guttation fluid from the leaves. Consequently, guttation fluid was collected from young maize and wheat plants, injected in an empty enclosure and sampled by PTR-MS. Methanol and a large number of other compounds were observed from guttation fluid. Recent studies have shown that guttation from agricultural crops frequently occurs in field conditions. Further research is required to find out the source strength of methanol emissions by this guttation

  20. [Transformation Mechanism and Sources of Secondary Inorganic Components in PM2.5 at an Agriculture Site (Quzhou) in the North China Plain in Summer].

    PubMed

    Chen, Shi-yi; Zeng, Li-min; Dong, Hua-bin; Zhu, Tong

    2015-10-01

    Simultaneously on-line measurements of major water-soluble inorganic ions and gaseous pollutants were performed from June 9 to July 11, 2014 at Quzhou, an agriculture site in the North China Plain using a gas-aerosol collector (GAC) and ion chromatograph (IC), aiming to track the diurnal variation rule of secondary inorganic components and gas-phase precursors as well as their interactions. The transformation mechanism and sources of fine particles (PM2.5) were also discussed. The results showed that these water-soluble ions in PM2.5 and their gas-phase precursors varied regularly. As the dominant ionic components of PM2.5 (accounting for 76.23%), the average concentrations of SO4(2-), NH4(+), NO3(-) were 26.28 μg x m(-3), 18.08 μg x m(-3) and 16.36 μg m(-3) respectively. Among the precursor gases, the NH3, generated from the discharges of local agricultural activities, displayed a significantly higher concentration at an average value of 44.85 μg x m(-3). The average fine sulfate and nitrate oxidation ratios (SOR and NOR) were SOR = 0.60, NOR = 0.30, revealing the remarkable characteristics of secondary pollution. As could be found from the relevant analysis, the NH4(+) of Quzhou showed well relations with NO3(-) and SO4(2-), and the environment here was rich of ammonia. The NH4(+) existed in the form of (NH4)2SO4 and the generation of NO3(-) was limited by the HNO3. From the analysis for the equilibrium of NH4NO3, we observed that the atmospheric environment of Quzhou was adverse to the generation and maintenance of NH4NO3 during the daytime,in contrast with the night. Integrated with the study, the results displayed that the secondary transformation was the main source of fine particles in Quzhou, and the NH3 from field and compost was the significant factor leading to the high value of S-N-A. PMID:26841585

  1. Spatial and temporal variations in non-point source losses of nitrogen and phosphorus in a small agricultural catchment in the Three Gorges Region.

    PubMed

    Chen, Chenglong; Gao, Ming; Xie, Deti; Ni, Jiupai

    2016-04-01

    Losses of agricultural pollutants from small catchments are a major issue for water quality in the Three Gorges Region. Solutions are urgently needed. However, before pollutant losses can be controlled, information about spatial and temporal variations in pollutant losses is needed. The study was carried out in the Wangjiagou catchment, a small agricultural catchment in Fuling District, Chongqing, and the data about non-point source losses of nitrogen and phosphorus was collected here. Water samples were collected daily by an automatic water sampler at the outlets of two subcatchments from 2012 to 2014. Also, samples of surface runoff from 28 sampling sites distributed through the subcatchments were collected during 12 rainfall events in 2014. A range of water quality variables were analyzed for all samples and were used to demonstrate the variation in non-point losses of nitrogen and phosphorus over a range of temporal and spatial scales and in different types of rainfall in the catchment. Results showed that there was a significant linear correlation between the mass concentrations of total nitrogen (TN) and nitrate (NO3-N) in surface runoff and that the relationship was maintained with changes in time. Concentrations of TN and NO3-N peaked after fertilizer was applied to crops in spring and autumn; concentrations decreased rapidly after the peak values in spring but declined slowly in autumn. N and P concentrations fluctuated more and showed a greater degree of dispersion during the spring crop cultivation period than those in autumn. Concentrations of TN and NO3-N in surface runoff were significantly and positively correlated with the proportion of the area that was planted with corn and mustard tubers, but were negatively correlated with the proportion of the area taken up with rice and mulberry plantations. The average concentrations of TN and NO3-N in surface runoff reached the highest level from the sampling points at the bottom of the land used for corn

  2. [Transformation Mechanism and Sources of Secondary Inorganic Components in PM2.5 at an Agriculture Site (Quzhou) in the North China Plain in Summer].

    PubMed

    Chen, Shi-yi; Zeng, Li-min; Dong, Hua-bin; Zhu, Tong

    2015-10-01

    Simultaneously on-line measurements of major water-soluble inorganic ions and gaseous pollutants were performed from June 9 to July 11, 2014 at Quzhou, an agriculture site in the North China Plain using a gas-aerosol collector (GAC) and ion chromatograph (IC), aiming to track the diurnal variation rule of secondary inorganic components and gas-phase precursors as well as their interactions. The transformation mechanism and sources of fine particles (PM2.5) were also discussed. The results showed that these water-soluble ions in PM2.5 and their gas-phase precursors varied regularly. As the dominant ionic components of PM2.5 (accounting for 76.23%), the average concentrations of SO4(2-), NH4(+), NO3(-) were 26.28 μg x m(-3), 18.08 μg x m(-3) and 16.36 μg m(-3) respectively. Among the precursor gases, the NH3, generated from the discharges of local agricultural activities, displayed a significantly higher concentration at an average value of 44.85 μg x m(-3). The average fine sulfate and nitrate oxidation ratios (SOR and NOR) were SOR = 0.60, NOR = 0.30, revealing the remarkable characteristics of secondary pollution. As could be found from the relevant analysis, the NH4(+) of Quzhou showed well relations with NO3(-) and SO4(2-), and the environment here was rich of ammonia. The NH4(+) existed in the form of (NH4)2SO4 and the generation of NO3(-) was limited by the HNO3. From the analysis for the equilibrium of NH4NO3, we observed that the atmospheric environment of Quzhou was adverse to the generation and maintenance of NH4NO3 during the daytime,in contrast with the night. Integrated with the study, the results displayed that the secondary transformation was the main source of fine particles in Quzhou, and the NH3 from field and compost was the significant factor leading to the high value of S-N-A.

  3. Spatial and temporal variations in non-point source losses of nitrogen and phosphorus in a small agricultural catchment in the Three Gorges Region.

    PubMed

    Chen, Chenglong; Gao, Ming; Xie, Deti; Ni, Jiupai

    2016-04-01

    Losses of agricultural pollutants from small catchments are a major issue for water quality in the Three Gorges Region. Solutions are urgently needed. However, before pollutant losses can be controlled, information about spatial and temporal variations in pollutant losses is needed. The study was carried out in the Wangjiagou catchment, a small agricultural catchment in Fuling District, Chongqing, and the data about non-point source losses of nitrogen and phosphorus was collected here. Water samples were collected daily by an automatic water sampler at the outlets of two subcatchments from 2012 to 2014. Also, samples of surface runoff from 28 sampling sites distributed through the subcatchments were collected during 12 rainfall events in 2014. A range of water quality variables were analyzed for all samples and were used to demonstrate the variation in non-point losses of nitrogen and phosphorus over a range of temporal and spatial scales and in different types of rainfall in the catchment. Results showed that there was a significant linear correlation between the mass concentrations of total nitrogen (TN) and nitrate (NO3-N) in surface runoff and that the relationship was maintained with changes in time. Concentrations of TN and NO3-N peaked after fertilizer was applied to crops in spring and autumn; concentrations decreased rapidly after the peak values in spring but declined slowly in autumn. N and P concentrations fluctuated more and showed a greater degree of dispersion during the spring crop cultivation period than those in autumn. Concentrations of TN and NO3-N in surface runoff were significantly and positively correlated with the proportion of the area that was planted with corn and mustard tubers, but were negatively correlated with the proportion of the area taken up with rice and mulberry plantations. The average concentrations of TN and NO3-N in surface runoff reached the highest level from the sampling points at the bottom of the land used for corn

  4. Urban Agriculture Program Planning Guide.

    ERIC Educational Resources Information Center

    Hemp, Paul E.; Ethridge, Jim

    Urban agriculture may be defined as those areas of agriculture that are practiced in metropolitan settings, plus knowledge and skills in agricultural subject areas which lead to vocational proficiency and improved quality of life or effective citizenship. Agriculture areas that are especially significant in urban settings include ornamental…

  5. Theme: Changes in Agricultural Education.

    ERIC Educational Resources Information Center

    Agricultural Education Magazine, 1997

    1997-01-01

    Includes "Changes in Agricultural Education in Tennessee" (Byerley, Todd); "Evolving Focus for Agricultural Education Graduates?" (Schlink); "Researching Adult Organizations in Agricultural Education" (Seevers, Dormody); "Past 25 Years" (Klein, Luft); "Agricultural Education" (Sibiga, Mannebach); "Don't Look Back" (Butcher); "Changes in…

  6. Historical contributions of phosphorus from natural and agricultural sources and implications for stream water quality, Cheney Reservoir watershed, south-central Kansas

    USGS Publications Warehouse

    Pope, Larry M.; Milligan, Chad R.; Mau, David Phillip

    2002-01-01

    An examination of soil cores collected from 43 nonagricultural coring sites in the Cheney Reservoir watershed of south-central Kansas was conducted by the U.S. Geological Survey in September 1999. The cores were collected as part of an ongoing cooperative study with the city of Wichita, Kansas. The 43 sites (mostly cemeteries) were thought to have total phosphorus concentrations in the soil that are representative of natural conditions (unaffected by human activity). The purpose of this report is to present the analysis and evaluation of these soil cores, to quantify the phosphorus contributions to Cheney Reservoir from natural and agricultural sources, and to provide estimates of stream-water-quality response to natural concentrations of total phosphorus in the soil. Analysis of soil cores from the 43 sites produced natural concentrations of total phosphorus that ranged from 74 to 539 milligrams per kilogram with a median concentration of 245 milligrams per kilogram in 2-inch soil cores and from 50 to 409 milligrams per kilogram with a median concentration of 166 milligrams per kilogram in 8-inch soil cores. Natural concentrations of total phosphorus in soil were statistically larger in samples from coring sites in the eastern half of the watershed than in samples from coring sites in the western half of the watershed. This result partly explains a previously determined west-to-east increase in total phosphorus yields in streams of the Cheney Reservoir watershed. A comparison of total phosphorus concentrations in soil under natural conditions to the historical mean total phosphorus concentration in agriculturally enriched bottom sediment in Cheney Reservoir indicated that agricultural activities within the watershed have increased total phosphorus concentrations in watershed soil that is transported in streams to about 2.9 times natural concentrations. Retention efficiencies for phosphorus and sediment historically transported to Cheney Reservoir were calculated

  7. Geospatial data resampling and resolution effects on watershed modeling: A case study using the agricultural non-point source pollution model

    USGS Publications Warehouse

    Usery, E.L.; Finn, M.P.; Scheidt, D.J.; Ruhl, S.; Beard, T.; Bearden, M.

    2004-01-01

    Researchers have been coupling geographic information systems (GIS) data handling and processing capability to watershed and waterquality models for many years. This capability is suited for the development of databases appropriate for water modeling. However, it is rare for GIS to provide direct inputs to the models. To demonstrate the logical procedure of coupling GIS for model parameter extraction, we selected the Agricultural Non-Point Source (AGNPS) pollution model. Investigators can generate data layers at various resolutions and resample to pixel sizes to support models at particular scales. We developed databases of elevation, land cover, and soils at various resolutions in four watersheds. The ability to use multiresolution databases for the generation of model parameters is problematic for grid-based models. We used database development procedures and observed the effects of resolution and resampling on GIS input datasets and parameters generated from those inputs for AGNPS. Results indicate that elevation values at specific points compare favorably between 3- and 30-m raster datasets. Categorical data analysis indicates that land cover classes vary significantly. Derived parameters parallel the results of the base GIS datasets. Analysis of data resampled from 30-m to 60-, 120-, 210-, 240-, 480-, 960-, and 1920-m pixels indicates a general degradation of both elevation and land cover correlations as resolution decreases. Initial evaluation of model output values for soluble nitrogen and phosphorous indicates similar degradation with resolution. ?? Springer-Verlag 2004.

  8. The seasonal dynamics of the stream sources and input flow paths of water and nitrogen of an Austrian headwater agricultural catchment.

    PubMed

    Exner-Kittridge, Michael; Strauss, Peter; Blöschl, Günter; Eder, Alexander; Saracevic, Ernis; Zessner, Matthias

    2016-01-15

    Our study examines the source aquifers and stream inputs of the seasonal water and nitrogen dynamics of a headwater agricultural catchment to determine the dominant driving forces for the seasonal dynamics in the surface water nitrogen loads and concentrations. We found that the alternating aquifer contributions throughout the year of the deep and shallow aquifers were the main cause for the seasonality of the nitrate concentration. The deep aquifer water typically contributed 75% of the total outlet discharge in the summer and 50% in the winter when the shallow aquifer recharges due to low crop evapotranspiration. The shallow aquifer supplied the vast majority of the nitrogen load to the stream due to the significantly higher total nitrogen concentration (11 mg-N/l) compared to the deep aquifer (0.50 mg-N/l). The main stream input pathway for the shallow aquifer nitrogen load was from the perennial tile drainages providing 60% of the total load to the stream outlet, while only providing 26% of the total flow volume. The diffuse groundwater input to the stream was the largest input to the stream (39%), but only supplied 27% to the total nitrogen load as the diffuse water was mostly composed of deep aquifer water. PMID:26562340

  9. Grassland agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agriculture in grassland environments is facing multiple stresses from: shifting demographics, declining and fragmented agricultural landscapes, declining environmental quality, variable and changing climate, volatile and increasing energy costs, marginal economic returns, and globalization. Degrad...

  10. Agricultural Production.

    ERIC Educational Resources Information Center

    Lehigh County Area Vocational-Technical School, Schnecksville, PA.

    This brochure describes the philosophy and scope of a secondary-level course in agricultural production. Addressed in the individual units of the course are the following topics: careers in agriculture and agribusiness, animal science and livestock production, agronomy, agricultural mechanics, supervised occupational experience programs, and the…

  11. Multi-purpose droop controllers incorporating a passivity-based stabilizer for unified control of electronically interfaced distributed generators including primary source dynamics.

    PubMed

    Azimi, Seyed Mohammad; Afsharnia, Saeed

    2016-07-01

    This paper presents multi-purpose droop controllers for electronically-interfaced distributed generators (EI-DGs). These controllers allow the micro-grids to operate in grid-connected mode, islanded mode and mode transition transients with a unique control configuration. The active and reactive-power sharing among EI-DGs are satisfied by the proposed droop controllers in islanded mode. On the other hand, in the grid-connected mode, the droop controllers adjust the output active and reactive-powers of EI-DGs at the pre-programmed constant levels. The provision of sufficient damping capability and maintenance of the transient stability in all operational modes of EI-DGs are warranted by the suggested stabilizer. This stabilizer, which is designed using the passivity-based control (PBC) approach, is incorporated in the droop controllers to dampen power-angle, frequency and voltage deviations during large transients using solely local information. The primary source dynamics of EI-DGs are also considered. It is analytically proven that the presence of the primary source dynamics leads to attenuation of the damping capability of EI-DGs in transients. To compensate the adverse effect of the primary source dynamics during transients a novel compensator is inserted in the frequency-droop loop. Finally, time-domain simulations are performed on a multi-resources MG to verify the analytical results compared to those obtained, based on a recently-developed strategy.

  12. Agricultural Compounds in Water and Birth Defects.

    PubMed

    Brender, Jean D; Weyer, Peter J

    2016-06-01

    Agricultural compounds have been detected in drinking water, some of which are teratogens in animal models. The most commonly detected agricultural compounds in drinking water include nitrate, atrazine, and desethylatrazine. Arsenic can also be an agricultural contaminant, although arsenic often originates from geologic sources. Nitrate has been the most studied agricultural compound in relation to prenatal exposure and birth defects. In several case-control studies published since 2000, women giving birth to babies with neural tube defects, oral clefts, and limb deficiencies were more likely than control mothers to be exposed to higher concentrations of drinking water nitrate during pregnancy. Higher concentrations of atrazine in drinking water have been associated with abdominal defects, gastroschisis, and other defects. Elevated arsenic in drinking water has also been associated with birth defects. Since these compounds often occur as mixtures, it is suggested that future research focus on the impact of mixtures, such as nitrate and atrazine, on birth defects. PMID:27007730

  13. Agricultural Compounds in Water and Birth Defects.

    PubMed

    Brender, Jean D; Weyer, Peter J

    2016-06-01

    Agricultural compounds have been detected in drinking water, some of which are teratogens in animal models. The most commonly detected agricultural compounds in drinking water include nitrate, atrazine, and desethylatrazine. Arsenic can also be an agricultural contaminant, although arsenic often originates from geologic sources. Nitrate has been the most studied agricultural compound in relation to prenatal exposure and birth defects. In several case-control studies published since 2000, women giving birth to babies with neural tube defects, oral clefts, and limb deficiencies were more likely than control mothers to be exposed to higher concentrations of drinking water nitrate during pregnancy. Higher concentrations of atrazine in drinking water have been associated with abdominal defects, gastroschisis, and other defects. Elevated arsenic in drinking water has also been associated with birth defects. Since these compounds often occur as mixtures, it is suggested that future research focus on the impact of mixtures, such as nitrate and atrazine, on birth defects.

  14. Identifying the sources of nitrate contamination of groundwater in an agricultural area (Haean basin, Korea) using isotope and microbial community analyses.

    PubMed

    Kim, Heejung; Kaown, Dugin; Mayer, Bernhard; Lee, Jin-Yong; Hyun, Yunjung; Lee, Kang-Kun

    2015-11-15

    An integrated study based on hydrogeochemical, microbiological and dual isotopic approaches for nitrate and sulfate was conducted to elucidate sources and biogeochemical reactions governing groundwater contaminants in different seasons and under different land use in a basin of Korea. The land use in the study area is comprised of forests (58.0%), vegetable fields (27.6%), rice paddy fields (11.4%) and others (3.0%). The concentrations of NO3-N and SO4(2-) in groundwater in vegetable fields were highest with 4.2-15.2 mg L(-1) and 1.6-19.7 mg L(-1) respectively, whereas under paddy fields NO3-N concentrations ranged from 0 to 10.7 mg L(-1) and sulfate concentrations were ~15 mg L(-1). Groundwater with high NO3-N concentrations of >10mgL(-1) had δ(15)N-NO3(-) values ranging from 5.2 to 5.9‰ and δ(18)O values of nitrate between 2.7 and 4.6‰ suggesting that the nitrate was mineralized from soil organic matter that was amended by fertilizer additions. Elevated concentrations of SO4(2-) with δ(34)S-SO4(2-) values between 1 and 6‰ in aquifers in vegetable fields indicated that a mixture of sulfate from atmospheric deposition, mineralization of soil organic matter and from synthetic fertilizers is the source of groundwater sulfate. Elevated δ(18)O-NO3(-) and δ(18)O-SO4(2-) values in samples collected from the paddy fields indicated that denitrification and bacterial sulfate reduction are actively occurring removing sulfate and nitrate from the groundwater. This was supported by high occurrences of denitrifying and sulfate reducing bacteria in groundwater of the paddy fields as evidenced by 16S rRNA pyrosequencing analysis. This study shows that dual isotope techniques combined with microbial data can be a powerful tool for identification of sources and microbial processes affecting NO3(-) and SO4(2-) in groundwater in areas with intensive agricultural land use. PMID:26204420

  15. Identifying the sources of nitrate contamination of groundwater in an agricultural area (Haean basin, Korea) using isotope and microbial community analyses.

    PubMed

    Kim, Heejung; Kaown, Dugin; Mayer, Bernhard; Lee, Jin-Yong; Hyun, Yunjung; Lee, Kang-Kun

    2015-11-15

    An integrated study based on hydrogeochemical, microbiological and dual isotopic approaches for nitrate and sulfate was conducted to elucidate sources and biogeochemical reactions governing groundwater contaminants in different seasons and under different land use in a basin of Korea. The land use in the study area is comprised of forests (58.0%), vegetable fields (27.6%), rice paddy fields (11.4%) and others (3.0%). The concentrations of NO3-N and SO4(2-) in groundwater in vegetable fields were highest with 4.2-15.2 mg L(-1) and 1.6-19.7 mg L(-1) respectively, whereas under paddy fields NO3-N concentrations ranged from 0 to 10.7 mg L(-1) and sulfate concentrations were ~15 mg L(-1). Groundwater with high NO3-N concentrations of >10mgL(-1) had δ(15)N-NO3(-) values ranging from 5.2 to 5.9‰ and δ(18)O values of nitrate between 2.7 and 4.6‰ suggesting that the nitrate was mineralized from soil organic matter that was amended by fertilizer additions. Elevated concentrations of SO4(2-) with δ(34)S-SO4(2-) values between 1 and 6‰ in aquifers in vegetable fields indicated that a mixture of sulfate from atmospheric deposition, mineralization of soil organic matter and from synthetic fertilizers is the source of groundwater sulfate. Elevated δ(18)O-NO3(-) and δ(18)O-SO4(2-) values in samples collected from the paddy fields indicated that denitrification and bacterial sulfate reduction are actively occurring removing sulfate and nitrate from the groundwater. This was supported by high occurrences of denitrifying and sulfate reducing bacteria in groundwater of the paddy fields as evidenced by 16S rRNA pyrosequencing analysis. This study shows that dual isotope techniques combined with microbial data can be a powerful tool for identification of sources and microbial processes affecting NO3(-) and SO4(2-) in groundwater in areas with intensive agricultural land use.

  16. Analysis of time-series of total and plant water stress levels using a dual-source energy balance model over agricultural crops and medium to low resolution thermal infra red remote sensing data

    NASA Astrophysics Data System (ADS)

    Boulet, Gilles; Mougenot, Bernard; Bahir, Malik; Fanise, Pascal; Saadi, Sameh; Simonneaux, Vincent; Chebbi, Wafa; Kassouk, Zeineb; Oualid, Toufik; Olioso, Albert; Lagouarde, Jean-Pierre; Le Dantec, Valérie; Rivalland, Vincent; Zribi, Mehrez; Lili-Chabaane, Zohra

    2015-04-01

    Detecting, monitoring and mapping plant water stress with remote sensing data is a crucial component of modern agricultural water management, especially in areas with scarce water resources such as the south and the eastern parts of the Mediterranean region. Developing efficient operational methods dedicated to those three actions is thus necessary to design observing systems for areas with a mixture of irrigated, rainfed and deficit irrigation agriculture. Those systems can assist managers in tasks such as early warning of drought, real time irrigated area mapping etc. A way to quantify plant and total water stress levels is to exploit the available surface temperature data from remote sensing as a signature of the surface energy balance, including the latent heat flux. Remotely sensed energy balance models enable to estimate evapotranspiration and the water status of continental surfaces. Two-source models, such as TSEB (Norman et al., 1995) allow deriving a rough estimate of the water stress of the vegetation instead of that of a soil-vegetation composite. For the latter, a realistic underlying assumption enables to invert two unknowns (evaporation and transpiration) from a single piece of information. This assumption states that, in most cases, vegetation is unstressed, and that if vegetation is stressed, evaporation is negligible. In the latter case, if vegetation stress is not properly accounted for, the resulting evaporation will decrease to unrealistic levels (negative fluxes) in order to maintain the same total surface temperature. Actual and potential transpiration rates are combined to derive an index of plant water stress applicable to low resolution data. Here, we evaluate time series of plant water stress indices in the Kairouan area in Central Tunisia in the last few years by comparing them with 1- maps of the irrigation sectors as well as rainfall data and 2- turbulent heat flux measurements obtained at low resolution (scintillometer, eddy

  17. Chemical mass balance (CMB) source apportionment and organic speciation of PM(2.5) in Missoula, Montana including the 2000 wildfire season

    NASA Astrophysics Data System (ADS)

    Ward, Tony J.

    A yearlong sampling program for PM2.5, Semi- Volatile Organic Compounds (SVOCs), and Volatile Organic Compounds (VOCs) was conducted in 2000/2001. The data were used in a Chemical Mass Balance (CMB) Source Apportionment Model (Version 8.0) to apportion the sources of PM2.5 in the Missoula Valley. Results showed that wood combustion contributed an average of 41% to the fine fraction throughout the year. The second largest source of PM 2.5 was diesel (19%), followed by ammonium nitrate (17%), the kraft recovery boilers from Smurfit-Stone Container (14%), other hog fuel boilers (6%), and street sand (5%). Results also showed that PM2.5 levels and contributions from sources were consistent on both sides of the Missoula Valley, but VOCs were twice as high in Missoula compared to Frenchtown. Another aspect of this program was to investigate the organic fraction of the Missoula Valley PM2.5 by evaluating a modified Federal Reference Method (FRM) PM2.5 sampler. A method comparison was also made between sampling for SVOCs using the modified PM2.5 sampler and in using a Hi-volume Polyurethane Foam (PUF) sampler. Results showed that the PM 2.5 PUF measured more of the lighter SVOCs compared to the Hi-vol PUF sampler. This is most likely the result of the higher flows through the Hi-vol PUF which ``strip'' the lighter organics from the surface of the filter. The wildland fires of summer 2000 comprised one of the most severe fire seasons is U.S. history, and had a direct impact on the city of Missoula. Sampling in Missoula was already in progress when the fires began and smoke started rolling into the Missoula Valley. Samples were collected before, during, and after the 2000 fire season, and a detailed characterization of particulate and gaseous emissions from extensive wildland fires was obtained. The 2000/2001 CMB Sampling Program data collected during the 2000 fire season suggest that the main health impacts to downwind populations reside in the fine particulate exposures

  18. [Effects of agricultural activities and transgenic crops on agricultural biodiversity].

    PubMed

    Zhang, Xi-Tao; Luo, Hong-Bing; Li, Jun-Sheng; Huang, Hai; Liu, Yong-Bo

    2014-09-01

    Agricultural biodiversity is a key part of the ecosystem biodiversity, but it receives little concern. The monoculture, environmental pollution and habitat fragmentation caused by agricultural activities have threatened agricultural biodiversity over the past 50 years. To optimize agricultural management measures for crop production and environmental protection, we reviewed the effects of agricultural activities, including cultivation patterns, plastic mulching, chemical additions and the cultivation of transgenic crops, on agricultural biodiversity. The results showed that chemical pesticides and fertilizers had the most serious influence and the effects of transgenic crops varied with other factors like the specific transgene inserted in crops. The environmental risk of transgenic crops should be assessed widely through case-by-case methods, particularly its potential impacts on agricultural biodiversity. It is important to consider the protection of agricultural biodiversity before taking certain agricultural practices, which could improve agricultural production and simultaneously reduce the environmental impacts.

  19. [Effects of agricultural activities and transgenic crops on agricultural biodiversity].

    PubMed

    Zhang, Xi-Tao; Luo, Hong-Bing; Li, Jun-Sheng; Huang, Hai; Liu, Yong-Bo

    2014-09-01

    Agricultural biodiversity is a key part of the ecosystem biodiversity, but it receives little concern. The monoculture, environmental pollution and habitat fragmentation caused by agricultural activities have threatened agricultural biodiversity over the past 50 years. To optimize agricultural management measures for crop production and environmental protection, we reviewed the effects of agricultural activities, including cultivation patterns, plastic mulching, chemical additions and the cultivation of transgenic crops, on agricultural biodiversity. The results showed that chemical pesticides and fertilizers had the most serious influence and the effects of transgenic crops varied with other factors like the specific transgene inserted in crops. The environmental risk of transgenic crops should be assessed widely through case-by-case methods, particularly its potential impacts on agricultural biodiversity. It is important to consider the protection of agricultural biodiversity before taking certain agricultural practices, which could improve agricultural production and simultaneously reduce the environmental impacts. PMID:25757330

  20. Environmental behavior and analysis of agricultural sulfur.

    PubMed

    Griffith, Corey M; Woodrow, James E; Seiber, James N

    2015-11-01

    Sulfur has been widely used for centuries as a staple for pest and disease management in agriculture. Presently, it is the largest-volume pesticide in use worldwide. This review describes the sources and recovery methods for sulfur, its allotropic forms and properties and its agricultural uses, including development and potential advantages of nanosulfur as a fungicide. Chemical and microbial reactivity, interactions in soil and water and analytical methods for determination in environmental samples and foodstuffs, including inexpensive analytical methods for sulfur residues in wine, beer and other food/beverage substrates, will be reviewed. The toxicology of sulfur towards humans and agriculturally important fungi is included, with some restrictions on use to promote safety. The review concludes with areas for which more research is warranted.

  1. Environmental behavior and analysis of agricultural sulfur.

    PubMed

    Griffith, Corey M; Woodrow, James E; Seiber, James N

    2015-11-01

    Sulfur has been widely used for centuries as a staple for pest and disease management in agriculture. Presently, it is the largest-volume pesticide in use worldwide. This review describes the sources and recovery methods for sulfur, its allotropic forms and properties and its agricultural uses, including development and potential advantages of nanosulfur as a fungicide. Chemical and microbial reactivity, interactions in soil and water and analytical methods for determination in environmental samples and foodstuffs, including inexpensive analytical methods for sulfur residues in wine, beer and other food/beverage substrates, will be reviewed. The toxicology of sulfur towards humans and agriculturally important fungi is included, with some restrictions on use to promote safety. The review concludes with areas for which more research is warranted. PMID:26108794

  2. Nitrate in groundwater and water sources used by riparian trees in an agricultural watershed: A chemical and isotopic investigation in southern Minnesota

    USGS Publications Warehouse

    Komor, S.C.; Magner, J.A.

    1996-01-01

    This study evaluates processes that affect nitrate concentrations in groundwater beneath riparian zones in an agricultural watershed. Nitrate pathways in the upper 2 m of groundwater were investigated beneath wooded and grass-shrub riparian zones next to cultivated fields. Because trees can be important components of the overall nitrate pathway in wooded riparian zones, water sources used by riparian trees and possible effects of trees on nitrate concentrations in groundwater were also investigated. Average nitrate concentrations in shallow groundwater beneath the cultivated fields were 5.5 mg/L upgradient of the wooded riparian zone and 3.5 mg/L upgradient of the grass-shrub zone. Shallow groundwater beneath the fields passed through the riparian zones and discharged into streams that had average nitrate concentrations of 8.5 mg/L (as N). Lateral variations of ??D values in groundwater showed that mixing among different water sources occurred beneath the riparian zones. In the wooded riparian zone, nitrate concentrations in shallow groundwater were diluted by upwelling, nitrate- poor, deep groundwater. Upwelling deep groundwater contained ammonium with a ??15N of 5??? that upon nitrification and mixing with nitrate in shallow groundwater caused nitrate ??15N values in shallow groundwater to decrease by as much as 19.5???. Stream water penetrated laterally beneath the wooded riparian zone as far as 19 m from the stream's edge and beneath the grass- shrub zone as far as 27 m from the stream's edge. Nitrate concentrations in shallow groundwater immediately upgradient of where it mixed with stream water averaged 0.4 mg/L in the wooded riparian zone and 0.8 mg/L near the grass-shrub riparian zone. Nitrate concentrations increased toward the streams because of mixing with nitrate-rich stream water. Because nitrate concentrations were larger in stream water than shallow groundwater, concentrated nitrate in the streams cannot have come from shallow groundwater at these

  3. Nitrate in ground water and water sources used by riparian trees in an agricultural watershed: A chemical and isotopic investigation in southern Minnesota

    USGS Publications Warehouse

    Komor, Stephen C.; Magner, J.

    1996-01-01

    This study evaluates processes that affect nitrate concentrations in groundwater beneath riparian zones in an agricultural watershed. Nitrate pathways in the upper 2 m of groundwater were investigated beneath wooded and grass-shrub riparian zones next to cultivated fields. Because trees can be important components of the overall nitrate pathway in wooded riparian zones, water sources used by riparian trees and possible effects of trees on nitrate concentrations in groundwater were also investigated. Average nitrate concentrations in shallow groundwater beneath the cultivated fields were 5.5 mg/L upgradient of the wooded riparian zone and 3.5 mg/L upgradient of the grass-shrub zone. Shallow groundwater beneath the fields passed through the riparian zones and discharged into streams that had average nitrate concentrations of 8.5 mg/L (as N). Lateral variations of δD values in groundwater showed that mixing among different water sources occurred beneath the riparian zones. In the wooded riparian zone, nitrate concentrations in shallow groundwater were diluted by upwelling, nitrate-poor, deep groundwater. Upwelling deep groundwater contained ammonium with a δ15N of 5‰ that upon nitrification and mixing with nitrate in shallow groundwater caused nitrate δ15N values in shallow groundwater to decrease by as much as 19.5‰. Stream water penetrated laterally beneath the wooded riparian zone as far as 19 m from the stream's edge and beneath the grass-shrub zone as far as 27 m from the stream's edge. Nitrate concentrations in shallow groundwater immediately upgradient of where it mixed with stream water averaged 0.4 mg/L in the wooded riparian zone and 0.8 mg/L near the grass-shrub riparian zone. Nitrate concentrations increased toward the streams because of mixing with nitrate-rich stream water. Because nitrate concentrations were larger in stream water than shallow groundwater, concentrated nitrate in the streams cannot have come from shallow groundwater at these

  4. The potential of vegetable oila s an alternate source of liquid fuel for agriculture in the Pacific Northwest - V: Final report, 1986--1987

    SciTech Connect

    Auld, D.L.; Davis, J.B.; Feldman, M.E.; Hall, M.C.; Hawley, K.N.; Korus, R.A.; Magenis, B.R.; Mahler, K.A.; Melville, D.E.; Mosgrove, D.L.

    1987-06-01

    This research was conducted to develop the technology necessary to produce, process, and utilize vegetable oil as a diesel fuel substitute for agricultural production in the Pacific Northwest. Additional studies were conducted to determine the economic threshold, to derive energy budgets for various crop production regions and to insure that expeller extracted meals would make acceptable animal feeds. This research was conducted by an integrated team of scientists from the University of Idaho which initiated efforts in this field in December of 1979. Experiments were conducted by agronomists, agricultural engineers, animal nutritionists, chemical engineers, and agricultural economists. This report summarizes data accumulated from April 1986 to May 1987 as part of USDA/ARS Research Agreement No. 58-7B30-2-402. Copies for this report can be obtained from the Director of the Idaho Agricultural Experiment Station, College of Agriculture, University of Idaho, Moscow, ID 83843.

  5. The potential of vegetable oil as an alternate source of liquid fuel for agriculture in the Pacific Northwest - IV: Final report, 1984-1986

    SciTech Connect

    Auld, D.L.; Hall, M.C.; Hawley, K.N.; Korus, R.A.; Madsen, J.P.; Mahler, K.A.; Mora, P.G.; Peterson, C.L.; Roelofsen, M.; Stibal, W.T.; Whitcraft, J.C.

    1986-01-01

    This research was conducted to develop the technology necessary to produce, process, and utilize vegtable oil as a diesel fuel substitute for agricultural production in the Pacific Northwest. Additional studies were conducted to determine the economic threshold, to derive energy budgets for various crop production regions, and to insure that expeller extracted meals would make acceptable animal feeds. This research was conducted by an integrated team of scientists from the University of Idaho which initiated efforts in this field in December of 1979. Experiments were conducted by agronomists, agricultural engineers, animal nutritionists, chemical engineers, and agricultural economists. This report summarized data accumulated from October 1984 to March 1986 as part of USDA/ARS Research Agreement No. 58-7B30-2-402. Copies of this report can be obtained from the Director of the Idaho Agricultural Experiment Station, College of Agriculture, University of Idaho, Moscow, ID 83843.

  6. Vocational Agriculture I.

    ERIC Educational Resources Information Center

    Patton, Bob; Harp, Keith

    These course materials are designed to provide a foundation of basic knowledge in production agriculture as a prelude to further education in vocational agriculture. The guide contains 6 sections and 22 units of instruction. Each unit includes all or most of eight basic components: performance objectives, suggested activities for the teacher,…

  7. Theme: Urban Agriculture.

    ERIC Educational Resources Information Center

    Ellibee, Margaret; And Others

    1990-01-01

    On the theme of secondary agricultural education in urban areas, this issue includes articles on opportunities, future directions, and implications for the profession; creative supervised experiences for horticulture students; floral marketing, multicultural education; and cultural diversity in urban agricultural education. (JOW)

  8. Agricultural Occupations Handbook.

    ERIC Educational Resources Information Center

    Lark, Floyd J.; Henderson, Billie

    This agricultural occupations handbook was developed from the Dictionary of Occupational Titles (DOT) and the U.S. Departments of Health, Education, and Welfare, and Labor publication, Vocational Education and Occupations. It includes the U.S. Office of Education coding for the instructional area of agriculture and the cluster coding for the…

  9. Long-Term Monitoring of Waterborne Pathogens and Microbial Source Tracking Markers in Paired Agricultural Watersheds under Controlled and Conventional Tile Drainage Management

    PubMed Central

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A.; Gannon, Victor; Gottschall, Natalie; Jokinen, Cassandra C.; Jones, Tineke H.; Khan, Izhar U. H.; Marti, Romain; Sunohara, Mark D.; Topp, Edward

    2014-01-01

    Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization. PMID:24727274

  10. Advancing agricultural greenhouse gas quantification*

    NASA Astrophysics Data System (ADS)

    Olander, Lydia; Wollenberg, Eva; Tubiello, Francesco; Herold, Martin

    2013-03-01

    increased emissions unless we improve production efficiencies and management. Developing countries currently account for about three-quarters of direct emissions and are expected to be the most rapidly growing emission sources in the future (FAO 2011). Reducing agricultural emissions and increasing carbon sequestration in the soil and biomass has the potential to reduce agriculture's contribution to climate change by 5.5-6.0 gigatons (Gt) of carbon dioxide equivalent (CO2eq)/year. Economic potentials, which take into account costs of implementation, range from 1.5 to 4.3 GT CO2eq/year, depending on marginal abatement costs assumed and financial resources committed, with most of this potential in developing countries (Smith et al 2007). The opportunity for mitigation in agriculture is thus significant, and, if realized, would contribute to making this sector carbon neutral. Yet it is only through a robust and shared understanding of how much carbon can be stored or how much CO2 is reduced from mitigation practices that informed decisions can be made about how to identify, implement, and balance a suite of mitigation practices as diverse as enhancing soil organic matter, increasing the digestibility of feed for cattle, and increasing the efficiency of nitrogen fertilizer applications. Only by selecting a portfolio of options adapted to regional characteristics and goals can mitigation needs be best matched to also serve rural development goals, including food security and increased resilience to climate change. Expansion of agricultural land also remains a major contributor of greenhouse gases, with deforestation, largely linked to clearing of land for cultivation or pasture, generating 80% of emissions from developing countries (Hosonuma et al 2012). There are clear opportunities for these countries to address mitigation strategies from the forest and agriculture sector, recognizing that agriculture plays a large role in economic and development potential. In this context

  11. Completed Research in Health, Physical Education, Recreation and Dance; Including International Sources. Volume 23. 1981 Edition. Covering Research Completed in 1980.

    ERIC Educational Resources Information Center

    Rothstein, Anne L., Ed.; Nelson, Jack, Ed.

    Citations of published research reports and abstracts of master's and doctoral theses completed during 1980 are included in the areas of health, physical education, recreation, dance, and allied fields in two sections of this three-section volume. The bibliography section contains listings of 1031 articles published in 113 periodicals. In a…

  12. Agricultural biosecurity.

    PubMed

    Waage, J K; Mumford, J D

    2008-02-27

    The prevention and control of new pest and disease introductions is an agricultural challenge which is attracting growing public interest. This interest is in part driven by an impression that the threat is increasing, but there has been little analysis of the changing rates of biosecurity threat, and existing evidence is equivocal. Traditional biosecurity systems for animals and plants differ substantially but are beginning to converge. Bio-economic modelling of risk will be a valuable tool in guiding the allocation of limited resources for biosecurity. The future of prevention and management systems will be strongly influenced by new technology and the growing role of the private sector. Overall, today's biosecurity systems are challenged by changing national priorities regarding trade, by new concerns about environmental effects of biological invasions and by the question 'who pays?'. Tomorrow's systems may need to be quite different to be effective. We suggest three changes: an integration of plant and animal biosecurity around a common, proactive, risk-based approach; a greater focus on international cooperation to deal with threats at source; and a commitment to refocus biosecurity on building resilience to invasion into agroecosystems rather than building walls around them.

  13. Modular Design of Processing and Storage Facilities for Small Volumes of Low and Intermediate Level Radioactive Waste including Disused Sealed Sources - 12372

    SciTech Connect

    Keene, David R.; Kumar Samanta, Susanta; Drace, Zoran

    2012-07-01

    There are a number of IAEA Member States generating relatively small quantities of radioactive waste and/or disused sealed sources in application of nuclear techniques in medicine, industry and research and in nuclear research centres having small research reactors. At present many of these Member States do not have facilities for processing and storing their radioactive wastes; notably in those countries with small quantities of generated radioactive wastes. In other Member States the existing waste processing and storage facilities (WPSF) are in need of varying degrees of upgrading in order to address new waste streams, incorporate new waste processing technologies, or expand interim storage capacities. The IAEA has developed a modular design approach for a WPSF that is based on a variety of modules for different waste stream treatment and conditioning processes. The modular WPSF design is elaborated in a substantial Design Engineering Package that will be published by IAEA as a technical report. The Design Engineering Package enables users to select the optimum waste processing and storage modules to meet their needs, and to specify the requirements for procurement of individual modules and their integration into a waste processing and storage facility. The Design Engineering Package is planned for publication by the IAEA in 2012 and is presented as: - A Design Engineering Package Summary document. - A supporting CD that contains: - Process module general specifications. - Process module interface specifications. - Design Engineering Package for process modules. - Sample technical specifications for design and construction of modular processing facility. - Design Engineering Package for storage modules. (authors)

  14. Growth performance and metabolic utilization of diets including starch, dextrin, maltose or glucose as carbohydrate source by gilthead sea bream (Sparus aurata) juveniles.

    PubMed

    Enes, P; Peres, H; Couto, A; Oliva-Teles, A

    2010-12-01

    The effect of dietary carbohydrate complexity on growth, feed utilization and activity of selected key liver enzymes of intermediary metabolism were studied in gilthead sea bream juveniles. Four isonitrogenous (50% crude protein) and isolipidic (16% crude lipids) diets were formulated to contain 20% of pregelatinized maize starch, dextrin, maltose or glucose. Triplicate groups of fish (117 g initial weight) were fed each diet to near satiation during 6 weeks. No effect of dietary carbohydrate on growth was noticed. Feed efficiency was lower in fish fed the glucose diet than the maltose and dextrin diets. The lowest protein efficiency ratio was observed in fish fed the glucose diet. Six hours after feeding, glycemia was higher in fish fed the glucose diet than the maltose and starch diets. Liver glycogen content was unaffected by dietary carbohydrate complexity. Hepatic glucokinase (GK) activity was higher in fish fed the glucose and the maltose diets, while higher pyruvate kinase (PK) activity was recorded in fish fed the glucose diet than in fish fed the starch diet. Fructose-1,6-bisphosphatase (FBPase) and glucose-6-phosphate dehydrogenase (G6PD) activities were higher in fish fed the starch diet compared to dextrin and glucose diets. Data suggest that dietary glucose and maltose are more effective than complex carbohydrates in enhancing liver glycolytic activity. Dietary glucose also seems to be more effective than starch in depressing liver gluconeogenic and lipogenic activities. Overall, dietary maltose, dextrin or starch was better utilized than glucose as energy source by gilthead sea bream juveniles.

  15. Theme: Future Programs of Agricultural Education.

    ERIC Educational Resources Information Center

    Lee, Jasper S.; And Others

    1985-01-01

    This issue, focusing on future programs of agricultural education, includes articles on the future of agriculture, bioelectronics, secondary programs, technical education in agriculture, young and adult farmer programs, instructional technology, and expanding opportunities for women. (CT)

  16. VOCATIONAL AGRICULTURE.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Research Coordinating Unit.

    TO ASSIST THOSE WHO MAKE DECISIONS RELATING TO EDUCATIONAL PROGRAMS IN AGRICULTURE, RECENT RESEARCH IN VOCATIONAL AGRICULTURE IS SUMMARIZED. A 1963 STUDY TREATS THE RELATIONSHIP BETWEEN WORK EXPERIENCE AND STUDENT CHARACTERISTICS, PLANS, AND ASPIRATIONS. STUDIES ON POST-SECONDARY EDUCATION CONCERN GUIDELINES FOR TECHNICIAN PROGRAMS, JUSTIFICATION…

  17. Agricultural Machinery - Equipment. Agricultural Cooperative Training. Vocational Agricluture. Revised.

    ERIC Educational Resources Information Center

    Sandlin, David, Comp.; And Others

    Designed for students enrolled in the Agricultural Cooperative Part-Time Training Program, this course of study contains 12 units on agricultural machinery mechanics. Units include (examples of unit topics in parentheses): introduction (agricultural mechanics as an occupation; safety--shop and equipment; use of holding devices, jacks, lifts, and…

  18. Cost-effectiveness and cost-benefit analysis of BMPs in controlling agricultural nonpoint source pollution in China based on the SWAT model.

    PubMed

    Liu, Ruimin; Zhang, Peipei; Wang, Xiujuan; Wang, Jiawei; Yu, Wenwen; Shen, Zhenyao

    2014-12-01

    Best management practices (BMPs) have been widely used in managing agricultural nonpoint source pollution (ANSP) at the watershed level. Most BMPs are related to land use, tillage management, and fertilizer levels. In total, seven BMP scenarios (Reforest1, Reforest2, No Tillage, Contour tillage, and fertilizer level 1-4) that are related to these three factors were estimated in this study. The objectives were to investigate the effectiveness and cost-benefit of these BMPs on ANSP reduction in a large tributary of the Three Gorges Reservoir (TGR) in China, which are based on the simulation results of the Soil and Water Assessment Tool (SWAT) model. The results indicated that reforestation was the most economically efficient of all BMPs, and its net benefits were up to CNY 4.36×10(7) years(-1) (about USD 7.08×10(6) years(-1)). Regarding tillage practices, no tillage practice was more environmentally friendly than other tillage practices, and contour tillage was more economically efficient. Reducing the local fertilizer level to 0.8-fold less than that of 2010 can yield a satisfactory environmental and economic efficiency. Reforestation and fertilizer management were more effective in reducing total phosphorus (TP), whereas tillage management was more effective in reducing total nitrogen (TN). When CNY 10,000 (about USD 162) was applied to reforestation, no tillage, contour tillage, and an 0.8-fold reduction in the fertilizer level, then annual TN load can be reduced by 0.08, 0.16, 0.11, and 0.04 t and annual TP load can be reduced by 0.04, 0.02, 0.01 and 0.03 t, respectively. The cost-benefit (CB) ratios of the BMPs were as follows: reforestation (207 %) > contour tillage (129 %) > no tillage (114 %) > fertilizer management (96 and 89 %). The most economical and effective BMPs can be designated as follows: BMP1 (returning arable land with slopes greater than 25° to forests and those lands with slopes of 15-25° to orchards), BMP2 (implementing no tillage

  19. 7 CFR 46.38 - Sundays and holidays included.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Sundays and holidays included. 46.38 Section 46.38 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Holidays § 46.38 Sundays and holidays included. Sundays and holidays shall be included in the...

  20. 7 CFR 46.38 - Sundays and holidays included.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Sundays and holidays included. 46.38 Section 46.38 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Holidays § 46.38 Sundays and holidays included. Sundays and holidays shall be included in the...

  1. 7 CFR 46.38 - Sundays and holidays included.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Sundays and holidays included. 46.38 Section 46.38 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Holidays § 46.38 Sundays and holidays included. Sundays and holidays shall be included in the...

  2. 7 CFR 46.38 - Sundays and holidays included.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Sundays and holidays included. 46.38 Section 46.38 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Holidays § 46.38 Sundays and holidays included. Sundays and holidays shall be included in the...

  3. 7 CFR 46.38 - Sundays and holidays included.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Sundays and holidays included. 46.38 Section 46.38 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Holidays § 46.38 Sundays and holidays included. Sundays and holidays shall be included in the...

  4. Agriculture Education. Agricultural Metal Working.

    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 agricultural metal working. The guide presents units of study in the following areas: (1) oxyacetylene welding, (2) arc welding, (3) sheet metal, (4) blueprint reading for welders and (5) job…

  5. Variation in Quantity, Source and Bioreactivity of Dissolved Organic Matter in Streams Draining Watersheds along a Gradient of Agricultural Land Use

    NASA Astrophysics Data System (ADS)

    Shang, P.; Lu, Y.; Jaffe, R.; Du, Y.; Findlay, R.

    2015-12-01

    In order to address the effects of agricultural land use on stream water dissolved organic matter (DOM), we sampled a regional group of second to third order streams draining watersheds along a gradient of percentage agricultural lands in northwestern Alabama, USA. Samples were collected under baseflow conditions, five different times over the year 2014. We analyzed dissolved organic carbon (DOC) concentrations, DOM optical properties (i.e. ultraviolet-visible and fluorescence spectrophotometry), and DOM bioreactivity over the course of 22 d incubation. We found that air temperature and antecedent precipitation intensity (API) were two major factors positively controlling DOC concentrations. High DOC concentrations were associated with high fluorescence index values, low percent contributions from terrestrially derived humic-like DOM fluorescence component (C1), and high percent contributions from microbially derived humic-like DOM fluorescence component (C3). We suggest that elevated microbial DOM production under high temperature and API was the primary reason for DOC enrichment in stream water. Percentage agricultural land was the secondary predictor of DOM characteristics. The percentages of forest land use within watersheds positively correlated with percent protein-like DOM fluorescence component (C4). DOC concentrations and relative abundance of humic-like DOM fluorescence components (C1, C2 and C3) were higher in agricultural streams than in forested streams, which could be attributed to flow path differences between agricultural and forested watersheds. Larger amount and percentage of bioreactive DOC was observed in agricultural streams, which might decrease oxygen level and impact fluvial ecosystem in downstream regions during degradation.

  6. Urban conservation agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetables are important sources of vitamins and nutrients for human nutrition. United States Department of Agriculture recommends filling half of the food plates with vegetables in every meal. While it is important in promoting good health, access to fresh vegetables is limited especially in urban ...

  7. Agricultural Microbiology.

    ERIC Educational Resources Information Center

    Brill, Winston J.

    1981-01-01

    Elucidates strategies for applying microbiological techniques to traditional agricultural practices. Discusses the manipulation of microorganisms that live with plants and also the problems involved in the introduction of new genes into crop plants by recombinant DNA methods. (CS)

  8. Agricultural Geophysics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The four geophysical methods predominantly used for agricultural purposes are resistivity, electromagnetic induction, ground penetrating radar (GPR), and time domain reflectometry (TDR). Resistivity and electromagnetic induction methods are typically employed to map lateral variations of apparent so...

  9. Recycling biosolids and lake-dredged materials to pasture-based animal agriculture: Alternative nutrient sources for forage productivity and sustainability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domestic sewage sludge or biosolids and lake-dredged materials are examples of materials that can be used to cut fertilizer costs in pasture-based animal agriculture. Sustainable biosolids and lake-dredged materials management is based upon controlling and influencing the quantity, quality and chara...

  10. Screening of postharvest agricultural wastes as alternative sources of peroxidases: characterization and kinetics of a novel peroxidase from lentil ( Lens culinaris L.) stubble.

    PubMed

    Hidalgo-Cuadrado, Nazaret; Pérez-Galende, Patricia; Manzano, Teresa; De Maria, Cándido Garcia; Shnyrov, Valery L; Roig, Manuel G

    2012-05-16

    Aqueous crude extracts of a series of plant wastes (agricultural, wild plants, residues from sports activities (grass), ornamental residues (gardens)) from 17 different plant species representative of the typical biodiversity of the Iberian peninsula were investigated as new sources of peroxidases (EC 1.11.1.7). Of these, lentil (Lens culinaris L.) stubble crude extract was seen to provide one of the highest specific peroxidase activities, catalyzing the oxidation of guaiacol in the presence of hydrogen peroxide to tetraguaiacol, and was used for further studies. For the optimum extraction conditions found, the peroxidase activity in this crude extract (110 U mL(-1)) did not vary for at least 15 months when stored at 4 °C (k(inact) = 0.146 year(-1), t(1/2 inact) = 4.75 year), whereas, for comparative purposes, the peroxidase activity (60 U mL(-1)) of horseradish (Armoracia rusticana L.) root crude extract, obtained and stored under the same conditions, showed much faster inactivation kinetics (k(inact) = 2.2 × 10(-3) day(-1), t(1/2 inact) = 315 days). Using guaiacol as an H donor and a universal buffer (see above), all crude extract samples exhibited the highest peroxidase activity in the pH range between 4 and 7. Once semipurified by passing the crude extract through hydrophobic chromatography on phenyl-Sepharose CL-4B, the novel peroxidase (LSP) was characterized as having a purity number (RZ) of 2.5 and three SDS-PAGE electrophoretic bands corresponding to molecular masses of 52, 35, and 18 kDa. The steady-state kinetic study carried out on the H(2)O(2)-mediated oxidation of guaiacol by the catalytic action of this partially purified peroxidase pointed to apparent Michaelian kinetic behavior (K(m)(appH(2)O(2)) = 1.87 mM; V(max)(appH(2)O(2)) = 6.4 mM min(-1); K(m)(app guaicol) = 32 mM; V(max)(app guaicol) = 9.1 mM min(-1)), compatible with the two-substrate ping-pong mechanism generally accepted for peroxidases. Finally, after the effectiveness of the crude

  11. Ecosystem services and agriculture: tradeoffs and synergies

    PubMed Central

    Power, Alison G.

    2010-01-01

    Agricultural ecosystems provide humans with food, forage, bioenergy and pharmaceuticals and are essential to human wellbeing. These systems rely on ecosystem services provided by natural ecosystems, including pollination, biological pest control, maintenance of soil structure and fertility, nutrient cycling and hydrological services. Preliminary assessments indicate that the value of these ecosystem services to agriculture is enormous and often underappreciated. Agroecosystems also produce a variety of ecosystem services, such as regulation of soil and water quality, carbon sequestration, support for biodiversity and cultural services. Depending on management practices, agriculture can also be the source of numerous disservices, including loss of wildlife habitat, nutrient runoff, sedimentation of waterways, greenhouse gas emissions, and pesticide poisoning of humans and non-target species. The tradeoffs that may occur between provisioning services and other ecosystem services and disservices should be evaluated in terms of spatial scale, temporal scale and reversibility. As more effective methods for valuing ecosystem services become available, the potential for ‘win–win’ scenarios increases. Under all scenarios, appropriate agricultural management practices are critical to realizing the benefits of ecosystem services and reducing disservices from agricultural activities. PMID:20713396

  12. Agriculture and land use issues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Large-scale biofuels development as a source of renewable energy will shift current dynamics in the agricultural sector that deliver food, feed, and fiber. This chapter examines the potential for modern agriculture to support a biofuels industry without comprimising its critical role for delivering ...

  13. Dioxin in the agricultural foodchain

    SciTech Connect

    Stevens, J.B. )

    1988-01-01

    Incineration of municipal solid waste is becoming an increasingly attractive alternative to the current practice of landfilling our garbage. However, the impact of this new practice on human health and the environment is not yet known. Emissions from MSW incinerators have been shown to contain numerous hazardous substances, including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polynuclear aromatic hydrocarbons and toxic metals. Of these emissions, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is viewed as the most toxic. Because of its lipophilic nature and environmental persistence, TCDD would be expected to biomagnify in food chains. Because many MSW incinerators are located in rural agricultural areas, it is thus very important to address the magnitude of human exposure to TCDD incinerator emissions from the agricultural food chain, i.e. ingestion by humans of garden produce, milk, beef, pork, lamb, chicken and eggs originating from the impact zone of the facility. This paper discusses this investigation the purpose of which was twofold: to quantify the food chain dose of TCDD relative to a commonly evaluated exposure pathway in risk assessment, inhalation of contaminated air; and to identify the major agricultural food chain sources of human exposure to TCDD.

  14. Water Quality Significance of Wetlands Receiving Agricultural Drainage

    NASA Astrophysics Data System (ADS)

    Stringfellow, W.; Sharon, B.; Engelage, S.; Hanlon, J.; Graham, J.; Burks, R.

    2007-12-01

    The San Joaquin Valley is one of the most productive agricultural regions in the world and this productivity is heavily dependent on irrigated agricultural. An inevitable consequence of irrigated agricultural is the generation of return-flows conveyed down-gradient in agricultural drains that eventually discharge to surface waters. Agricultural drainage often has poor water quality characteristics, but demand for water in California is high and agricultural drainage is often diverted for secondary use, including the maintenance of ponds and wetlands. Additionally, agricultural drainage often discharges into riparian wetlands, rather than into the open river channel. In this study we tested the hypothesis that wetlands were mitigating or buffering the impact of agricultural drainage and that discharge of agricultural drainage into wetland buffer zones would provide water quality benefits. Water samples were collected at wetland, agricultural, and mixed drainages in the San Joaquin River basin and analyzed for a broad array of physical and chemical water quality parameters, including nutrients and organic carbon. At selected wetlands, input-output studies were conducted to determine wetland specific water quality effects. The water quality of drainages influenced by wetlands was compared to drainages that were predominantly influenced by other types of land-use. Wetland influenced drainages are more likely to have higher DOC concentrations that other drainages, including agricultural and mixed urban-agricultural drains. Wetland dominated drainages had lower nitrates than agricultural drainages and studies of individual wetlands demonstrated that wetlands remove soluble phosphate and nitrate, but produce DOC and biochemical oxygen demand (BOD). Overall land use in a drainage was a less significant determinant of water quality than soil type and the presence or absence of wetlands. The specific trihalomethane formation potential (THMFP) of the DOC from wetland

  15. Application of multiple geochemical indicators, including the stable isotopes of water, to differentiate water quality evolution in a region influenced by various agricultural practices and domestic wastewater treatment and disposal.

    PubMed

    Butler, Thomas W

    2007-12-15

    Spatial and temporal variations in groundwater chemistry indicate that the use of low TDS lake water for irrigation, on land located just south of the City of Dixon, Solano County, California, is primarily responsible for improving groundwater quality with regards to salts. The stable isotopes of water further support this finding and suggest that TDS concentrations decrease as groundwater evolves to a more highly evaporated state. This seemingly contradictory finding was primarily attributed to infiltration of low TDS Lake Berryessa surface water, which has an isotopic signature indicative of an evaporated source and is used extensively for irrigation in the area, mixing with poorer quality locally recharged shallow groundwater. Geochemical modeling using the program PHREEQC further supports the anthropogenic aquifer freshening hypotheses through computed reductions in the saturation state of carbonate minerals in the vicinity of land irrigated by lake derived water, which is undersaturated with regards to modeled carbonates. Additionally, delta(18)O and delta(2)H were found to be useful in estimating climatic variables such as temperature and humidity, illustrating the potential for applying these models in hydrologic investigations within the area. It was however found that USDA NRCS soils data and measured water chemistry were not well correlated and thus the use of soils classifications to assess potential groundwater quality impacts was of limited utility.

  16. Landscape effects of a non-native grass facilitate source populations of a native generalist bug, Stenotus rubrovittatus, in a heterogeneous agricultural landscape.

    PubMed

    Yoshioka, A; Takada, M B; Washitani, I

    2014-01-01

    Non-native plant species can provide native generalist insects, including pests, with novel food and habitats. It is hypothesized that local and landscape-level abundances of non-native plants can affect the population size of generalist insects, although generalists are assumed to be less sensitive to habitat connectivity than specialists. In a heterogeneous landscape in Japan, the relationship between the density of a native pest of rice (Stenotus rubrovittatus (Matsumura) (Heteroptera: Miridae)) and the abundance of Italian ryegrass (Lolium multiflorum Lam. (Poales: Poaceae)), a non-native meadow grass known to facilitate S. rubrovittatus, was analyzed. Statistical analyses of data on bug density, vegetation, and the spatial distribution of fallow fields and meadows dominated by Italian ryegrass, obtained by field surveys, demonstrated that local and landscape-level abundances of Italian ryegrass (the unmowed meadow areas within a few hundred meters of a sampling plot) positively affected bug density before its immigration into rice fields. Our findings suggest that a generalist herbivorous insect that prefers non-native plants responds to spatial availability and connectivity of plant species patches at the metapopulation level. Fragmentation by selective mowing that decreases the total area of source populations and increases the isolation among them would be an effective and environmentally-friendly pest management method.

  17. Landscape Effects of a Non-Native Grass Facilitate Source Populations of a Native Generalist Bug, Stenotus rubrovittatus, in a Heterogeneous Agricultural Landscape

    PubMed Central

    Yoshioka, A.; Takada, M. B.; Washitani, I.

    2014-01-01

    Non-native plant species can provide native generalist insects, including pests, with novel food and habitats. It is hypothesized that local and landscape-level abundances of non-native plants can affect the population size of generalist insects, although generalists are assumed to be less sensitive to habitat connectivity than specialists. In a heterogeneous landscape in Japan, the relationship between the density of a native pest of rice (Stenotus rubrovittatus (Matsumura) (Heteroptera: Miridae)) and the abundance of Italian ryegrass (Lolium multiflorum Lam. (Poales: Poaceae)), a non-native meadow grass known to facilitate S. rubrovittatus, was analyzed. Statistical analyses of data on bug density, vegetation, and the spatial distribution of fallow fields and meadows dominated by Italian ryegrass, obtained by field surveys, demonstrated that local and landscape-level abundances of Italian ryegrass (the unmowed meadow areas within a few hundred meters of a sampling plot) positively affected bug density before its immigration into rice fields. Our findings suggest that a generalist herbivorous insect that prefers non-native plants responds to spatial availability and connectivity of plant species patches at the metapopulation level. Fragmentation by selective mowing that decreases the total area of source populations and increases the isolation among them would be an effective and environmentally-friendly pest management method. PMID:25205015

  18. EVALUATION OF SIGNIFICANT ANTHROPOGENIC SOURCES OF RADIATIVELY IMPORTANT TRACE GASES

    EPA Science Inventory

    The report is an initial evaluation of significant anthropogenic sources of radiatively important trace gases. missions of greenhouse gases from human activities--including fossil fuel combustion, industrial/agricultural activities, and transportation--contribute to the increasin...

  19. Economic Drought Impact on Agriculture: analysis of all agricultural sectors affected

    NASA Astrophysics Data System (ADS)

    Gil, M.; Garrido, A.; Hernández-Mora, N.

    2012-04-01

    The analysis of drought impacts is essential to define efficient and sustainable management and mitigation. In this paper we present a detailed analysis of the impacts of the 2004-2008 drought in the agricultural sector in the Ebro river basin (Spain). An econometric model is applied in order to determine the magnitude of the economic loss attributable to water scarcity. Both the direct impacts of drought on agricultural productivity and the indirect impacts of drought on agricultural employment and agroindustry in the Ebro basin are evaluated. The econometric model measures losses in the economic value of irrigated and rainfed agricultural production, of agricultural employment and of Gross Value Added both from the agricultural sector and the agro-industrial sector. The explanatory variables include an index of water availability (reservoir storage levels for irrigated agriculture and accumulated rainfall for rainfed agriculture), a price index representative of the mix of crops grown in each region, and a time variable. The model allows for differentiating the impacts due to water scarcity from other sources of economic losses. Results show how the impacts diminish as we approach the macro-economic indicators from those directly dependent on water abstractions and precipitation. Sectors directly dependent on water are the most affected with identifiable economic losses resulting from the lack of water. From the management perspective implications of these findings are key to develop mitigation measures to reduce drought risk exposure. These results suggest that more open agricultural markets, and wider and more flexible procurement strategies of the agro-industry reduces the socio-economic exposure to drought cycles. This paper presents the results of research conducted under PREEMPT project (Policy relevant assessment of the socioeconomic effects of droughts and floods, ECHO - grant agreement # 070401/2010/579119/SUB/C4), which constitutes an effort to provide

  20. IDENTIFICATION AND CHARACTERIZATION OF FIVE NON- TRADITIONAL SOURCE CATEGORIES: CATASTROPHIC/ACCIDENTAL RELEASES, VEHICLE REPAIR FACILITIES, RECYCLING, PESTICIDE APPLICATION, AND AGRICULTURAL OPERATIONS

    EPA Science Inventory

    The report gives results of work that is part of EPA's program to identify and characterize emissions sources not currently accounted for by either the existing Aerometric Information Retrieval System (AIRS) or State Implementation Plan (SIP) area source methodologies and to deve...

  1. Advancing agricultural greenhouse gas quantification*

    NASA Astrophysics Data System (ADS)

    Olander, Lydia; Wollenberg, Eva; Tubiello, Francesco; Herold, Martin

    2013-03-01

    increased emissions unless we improve production efficiencies and management. Developing countries currently account for about three-quarters of direct emissions and are expected to be the most rapidly growing emission sources in the future (FAO 2011). Reducing agricultural emissions and increasing carbon sequestration in the soil and biomass has the potential to reduce agriculture's contribution to climate change by 5.5-6.0 gigatons (Gt) of carbon dioxide equivalent (CO2eq)/year. Economic potentials, which take into account costs of implementation, range from 1.5 to 4.3 GT CO2eq/year, depending on marginal abatement costs assumed and financial resources committed, with most of this potential in developing countries (Smith et al 2007). The opportunity for mitigation in agriculture is thus significant, and, if realized, would contribute to making this sector carbon neutral. Yet it is only through a robust and shared understanding of how much carbon can be stored or how much CO2 is reduced from mitigation practices that informed decisions can be made about how to identify, implement, and balance a suite of mitigation practices as diverse as enhancing soil organic matter, increasing the digestibility of feed for cattle, and increasing the efficiency of nitrogen fertilizer applications. Only by selecting a portfolio of options adapted to regional characteristics and goals can mitigation needs be best matched to also serve rural development goals, including food security and increased resilience to climate change. Expansion of agricultural land also remains a major contributor of greenhouse gases, with deforestation, largely linked to clearing of land for cultivation or pasture, generating 80% of emissions from developing countries (Hosonuma et al 2012). There are clear opportunities for these countries to address mitigation strategies from the forest and agriculture sector, recognizing that agriculture plays a large role in economic and development potential. In this context

  2. Agricultural Biodiversity.

    ERIC Educational Resources Information Center

    Postance, Jim

    1998-01-01

    The extinction of farm animals and crops is rarely brought up during discussions of endangered species and biodiversity; however, the loss of diversity in crops and livestock threatens the sustainability of agriculture. Presents three activities: (1) "The Colors of Diversity"; (2) "Biodiversity among Animals"; and (3) "Heirloom Plants." Discusses…

  3. AGRICULTURAL EDUCATION.

    ERIC Educational Resources Information Center

    STEVENS, GLENN Z.

    FEDERAL LEGISLATION HAS PROVIDED FOR PUBLIC PROGRAMS OF OCCUPATIONAL AGRICULTURE EDUCATION IN LAND GRANT COLLEGES AND UNIVERSITIES, LOCAL SCHOOL DISTRICTS, AND MANPOWER DEVELOPMENT PROGRAMS. PROGRAM OBJECTIVES SHOULD BE TO DEVELOP KNOWLEDGE AND SKILLS, PROVIDE OCCUPATIONAL GUIDANCE AND PLACEMENT, AND DEVELOP ABILITIES IN HUMAN RELATIONS AND…

  4. AGRICULTURAL EXTENSION.

    ERIC Educational Resources Information Center

    FARQUHAR, R.N.

    AUSTRALIAN AGRICULTURAL EXTENSION HAS LONG EMPHASIZED TECHNICAL ADVISORY SERVICE AT THE EXPENSE OF THE SOCIOECONOMIC ASPECTS OF FARM PRODUCTION AND FARM LIFE. ONLY IN TASMANIA HAS FARM MANAGEMENT BEEN STRESSED. DEMANDS FOR THE WHOLE-FARM APPROACH HAVE PRODUCED A TREND TOWARD GENERALISM FOR DISTRICT OFFICERS IN MOST STATES. THE FEDERAL GOVERNMENT,…

  5. Distribution and mobility of heavy elements in floodplain agricultural soils along the Ibar River (Southern Serbia and Northern Kosovo). Chemometric investigation of pollutant sources and ecological risk assessment.

    PubMed

    Barać, Nemanja; Škrivanj, Sandra; Bukumirić, Zoran; Živojinović, Dragana; Manojlović, Dragan; Barać, Milan; Petrović, Rada; Ćorac, Aleksandar

    2016-05-01

    This work investigates the influence of a high-magnitude flood event on heavy elements (HEs) pollution and mobility in the agricultural soils along Ibar River in Southern Serbia and Northern Kosovo. The study area was one of the most important Pb/Zn industrial regions in Europe. Soil samples (n = 50) collected before and after the floods in May 2014 were subjected to the sequential extraction procedure proposed by the Community Bureau of Reference (BCR). The results indicated that the floods significantly increased not only the pseudo total concentrations of HEs in the soil but also their mobile and potentially bioavailable amounts. Moreover, higher concentrations (both pseudo total and potentially bioavailable) were found in the agricultural soils closer to the industrial hotspots. Principal component analysis and hierarchical cluster analysis successfully grouped the analyzed elements according to their anthropogenic or natural origin. The floods significantly increased the potential ecological risk of HEs associated with Pb/Zn industrial activities in the study area. The potential ecological risk of Cd after the floods was highest and should be of special concern. PMID:26822217

  6. Using Nitrate N and O Isotope Ratios to Identify Nitrate Sources and Dominant Nitrogen Cycling Processes in a 12ha Tile Drained Dryland Agricultural Field in the Palouse Basin of Eastern Washington State

    NASA Astrophysics Data System (ADS)

    Kelley, C. J.; Keller, C. K.; Evans, R. D.; Orr, C. H.; Smith, J. L.

    2010-12-01

    Agricultural systems are a leading source of reactive nitrogen to aquatic and atmospheric ecosystem. Understanding how anthropogenic nitrogen sources are cycled during transport from agricultural systems to aquatic and atmospheric systems is essential to identify the sink(s) of missing nitrogen and improve nitrogen management. Here we use natural nitrate 15N and 18O isotope abundances to determine the timing of nitrogen cycling process and to identify the source of nitrate discharged from a tile drained section of the WSU Cook Agronomy Farm. Previous research at the Cook Farm has shown that 5% to 20% of fertilizer nitrogen leaves the system as nitrate through the tile-drain. Identifying the timing of nitrogen cycling events and identifying the source(s) of tile drain nitrate is the first step to reduce nitrogen loss to aquatic systems bordering agricultural land. Throughout the 5 year study period δ18Onitrate averaged -1.26±1.48‰, indicating that nitrate-oxygen isotopes were not being enriched. Tile drain nitrate δ15N varied seasonally from -0.48‰ in the winter to +9.24‰ during the summer with an average of +3.19±2.62‰. The lack of nitrate-oxygen enrichment during the study period indicates that nitrification is the dominant nitrogen cycling process in the tile drained soil. The expected δ18Onitrate from nitrification based on the nitrification equation is -2.0‰, also supporting the claim that nitrification is the dominant nitrogen cycling process in the soil drained by the tile drain system. The large range of nitrate δ15N overlaps the expected isotope values for nitrate from nitrified synthetic nitrogen fertilizers and soil organic nitrogen. Nitrate-nitrogen and nitrate-oxygen isotope abundances have shown that nitrate in high nitrate concentration TD discharge originates from nitrification of reduced nitrogen fertilizers and nitrate in low nitrate concentration TD discharge originates from nitrification of; 1) soil organic nitrogen, 2) biotically

  7. Agricultural and urban pollution

    NASA Technical Reports Server (NTRS)

    Brehmer, M. L.

    1972-01-01

    The degradation produced by the introduction of agricultural and urban wastes into estuarine systems, with emphasis on the Chesapeake Bay area, is discussed. The subjects presented are: (1) effects of sediment loading and (2) organic and nutrient loading problems. The impact of high turbidity on the biological life of the bay is analyzed. The sources of nutrients which produce over-enrichment of the waters and the subsequent production of phytoplankton are examined.

  8. Conducting an agricultural life cycle assessment: challenges and perspectives.

    PubMed

    Caffrey, Kevin R; Veal, Matthew W

    2013-01-01

    Agriculture is a diverse field that produces a wide array of products vital to society. As global populations continue to grow the competition for natural resources will increase pressure on agricultural production of food, fiber, energy, and various high value by-products. With elevated concerns related to environmental impacts associated with the needs of a growing population, a life cycle assessment (LCA) framework can be used to determine areas of greatest impact and compare reduction strategies for agricultural production systems. The LCA methodology was originally developed for industrial operations but has been expanded to a wider range of fields including agriculture. There are various factors that increase the complexity of determining impacts associated with agricultural production including multiple products from a single system, regional and crop specific management techniques, temporal variations (seasonally and annually), spatial variations (multilocation production of end products), and the large quantity of nonpoint emission sources. The lack of consistent methodology of some impacts that are of major concern to agriculture (e.g., land use and water usage) increases the complexity of this analysis. This paper strives to review some of these issues and give perspective to the LCA practitioner in the field of agriculture. PMID:24391463

  9. Conducting an Agricultural Life Cycle Assessment: Challenges and Perspectives

    PubMed Central

    Caffrey, Kevin R.; Veal, Matthew W.

    2013-01-01

    Agriculture is a diverse field that produces a wide array of products vital to society. As global populations continue to grow the competition for natural resources will increase pressure on agricultural production of food, fiber, energy, and various high value by-products. With elevated concerns related to environmental impacts associated with the needs of a growing population, a life cycle assessment (LCA) framework can be used to determine areas of greatest impact and compare reduction strategies for agricultural production systems. The LCA methodology was originally developed for industrial operations but has been expanded to a wider range of fields including agriculture. There are various factors that increase the complexity of determining impacts associated with agricultural production including multiple products from a single system, regional and crop specific management techniques, temporal variations (seasonally and annually), spatial variations (multilocation production of end products), and the large quantity of nonpoint emission sources. The lack of consistent methodology of some impacts that are of major concern to agriculture (e.g., land use and water usage) increases the complexity of this analysis. This paper strives to review some of these issues and give perspective to the LCA practitioner in the field of agriculture. PMID:24391463

  10. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Aquaculture, including ornamental fish. 1437.303 Section 1437.303 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS NONINSURED CROP...

  11. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Aquaculture, including ornamental fish. 1437.303 Section 1437.303 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS NONINSURED CROP...

  12. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Aquaculture, including ornamental fish. 1437.303 Section 1437.303 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY CREDIT CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS NONINSURED CROP...

  13. Utility of a Two-source Energy Balance Approach for Daily Mapping of Landsat-scale Fluxes Over Irrigated Agriculture in a Desert Environment

    NASA Astrophysics Data System (ADS)

    Houborg, R.; McCabe, M. F.; Rosas Aguilar, J.; Anderson, M. C.; Hain, C.

    2014-12-01

    The Middle East and North Africa (MENA) region is an area characterized by limited fresh water resources, an often inefficient use of these, and relatively poor in-situ monitoring as a result of sparse meteorological observations. Enhanced satellite-based monitoring systems are needed for aiding local water resource and agricultural management activities in these data poor arid environments. A multi-sensor and multi-scale land-surface flux monitoring capacity is being implemented over parts of MENA in order to provide meaningful decision support at relevant spatiotemporal scales. The integrated modeling system uses the Atmosphere-Land Exchange Inverse (ALEXI) model and associated flux disaggregation scheme (DisALEXI), and the Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM) in conjunction with model reanalysis data and remotely sensed data from polar orbiting (Landsat and MODIS; MODerate resolution Imaging Spectroradiometer) and geostationary (MSG; Meteosat Second Generation) satellite platforms to facilitate daily estimates of land surface fluxes down to sub-field scale (i.e. 30 m). Within this modeling system, thermal infrared satellite data provide information about the sub-surface moisture status and plant stress, obviating the need for precipitation input and error-prone soil surface characterizations. In this study, the integrated ALEXI-DisALEXI-STARFM framework is applied over an irrigated agricultural region in Saudi Arabia, and the daily estimates of Landsat scale water, energy and carbon fluxes are evaluated against available flux tower observations and other independent in-situ and satellite-based records. The study addresses the challenges associated with time-continuous sub-field scale mapping of land-surface fluxes in a harsh desert environment, and looks into the optimization of model descriptions and parameterizations and meteorological forcing and vegetation inputs for application over these regions.

  14. Vocational Agriculture II.

    ERIC Educational Resources Information Center

    Harp, Keith; Steward, Jim

    This curriculum guide was developed for second-year courses in vocational agriculture in Oklahoma. The curriculum contains 5 sections organized in 16 instructional units. The units follow a standard format established in 1970 for development of instructional materials for all Oklahoma vocational teachers. This format includes eight basic…

  15. Nanotechnology in Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An overview is given of the application of nanotechnology to agriculture. This is an active field of R&D, where a large number of findings and innovations have been reported. For example, in soil management, applications reported include nanofertilizers, soil binders, water retention aids, and nut...

  16. Agriculture. Poultry Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for poultry, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task list.…

  17. Agriculture. Sheep Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for sheep, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task list. Each…

  18. Agriculture. Swine Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for swine, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task list. Each…

  19. Agriculture. Dairy Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for dairy livestock, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task…

  20. Agriculture. Beef Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for beef livestock, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task…

  1. Real-Time N2O Gas Detection System for Agricultural Production Using a 4.6-μm-Band Laser Source Based on a Periodically Poled LiNbO3 Ridge Waveguide

    PubMed Central

    Tokura, Akio; Asobe, Masaki; Enbutsu, Koji; Yoshihara, Toshihiro; Hashida, Shin-nosuke; Takenouchi, Hirokazu

    2013-01-01

    This article describes a gas monitoring system for detecting nitrous oxide (N2O) gas using a compact mid-infrared laser source based on difference-frequency generation in a quasi-phase-matched LiNbO3 waveguide. We obtained a stable output power of 0.62 mW from a 4.6-μm-band continuous-wave laser source operating at room temperature. This laser source enabled us to detect atmospheric N2O gas at a concentration as low as 35 parts per billion. Using this laser source, we constructed a new real-time in-situ monitoring system for detecting N2O gas emitted from potted plants. A few weeks of monitoring with the developed detection system revealed a strong relationship between nitrogen fertilization and N2O emission. This system is promising for the in-situ long-term monitoring of N2O in agricultural production, and it is also applicable to the detection of other greenhouse gases. PMID:23921829

  2. Dry fermentation of agricultural residues

    NASA Astrophysics Data System (ADS)

    Jewell, W. J.; Chandler, J. A.; Dellorto, S.; Fanfoni, K. J.; Fast, S.; Jackson, D.; Kabrick, R. M.

    1981-09-01

    A dry fermentation process is discussed which converts agricultural residues to methane, using the residues in their as produced state. The process appears to simplify and enhance the possibilities for using crop residues as an energy source. The major process variables investigated include temperature, the amount and type of inoculum, buffer requirements, compaction, and pretreatment to control the initial available organic components that create pH problems. A pilot-scale reactor operation on corn stover at a temperature of 550 C, with 25 percent initial total solids, a seed-to-feed ratio of 2.5 percent, and a buffer-to-feed ratio of 8 percent achieved 33 percent total volatile solids destruction in 60 days. Volumetric biogas yields from this unit were greater than 1 vol/vol day for 12 days, and greater than 0.5 vol/vol day for 32 days, at a substrate density of 169 kg/m (3).

  3. Proceedings: Agricultural Technology Alliance

    SciTech Connect

    1997-09-01

    This report is a compilation of field trip overviews, presentations and committee reports from the EPRI-ATA meeting held in Boise, Idaho, May 28-30, 1997. The field trips consisted of an Agriculture and Aquaculture Tour, a tour of Idaho as America's Seed Supplier, and a Production of Milk, Cheese and Electricity tour. Presentations and committee reports include the following: (1) Idaho Seed Industry; (2) Controlled Environment Agriculture; (3) Irrigation in the North West: An Overview; (4) Drip Irrigation; (5) Sprinkler Irrigation; (6) Current Status of the ATA; (7) ATA Office Report; (8) Committee Reports; (9) Steering Committee Minutes.

  4. Skill Sheets for Agricultural Mechanics.

    ERIC Educational Resources Information Center

    Iowa State Univ. of Science and Technology, Ames. Dept. of Agricultural Education.

    This set of 33 skill sheets for agricultural mechanics was developed for use in high school and vocational school agricultural mechanics programs. Some sheets teach operational procedures while others are for simple projects. Each skill sheet covers a single topic and includes: (1) a diagram, (2) a step-by-step construction or operational…

  5. Genetic Technology and Agricultural Development

    ERIC Educational Resources Information Center

    Staub, William J.; Blase, Melvin G.

    1971-01-01

    Examines the nature, application, limits and potential of applied genetics in plant breeding as a factor in South Asian agricultural development. Concludes other factors were also present in recent agricultural growth, and indicates some economic implications of continued growth, including problems of employment of displaced rural workers. (AL)

  6. Agricultural Science--Striving for Excellence.

    ERIC Educational Resources Information Center

    Budke, Wesley E.; And Others

    1991-01-01

    Six articles examine several of the critical components of program and personnel development in agricultural science including linkages between agriscience and natural resources teachers and high school science teachers, science in agriculture, biological science applications, and hydroponics. (JOW)

  7. Agricultural Business and Management Materials for Agricultural Education Programs. Core Agricultural Education Curriculum, Central Cluster.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana. Office of Agricultural Communications and Education.

    This curriculum guide contains 5 teaching units for 44 agricultural business and management cluster problem areas. These problem areas have been selected as suggested areas of study to be included in a core curriculum for secondary students enrolled in an agricultural education program. The five units are as follows: (1) agribusiness operation and…

  8. Carbon balance of Russian agricultural land

    NASA Astrophysics Data System (ADS)

    Schepaschenko, D.; Shvidenko, A.; Schepaschenko, M.

    2012-04-01

    Russia managed 218.7 mln ha agricultural land (2009) in accordance with national statistics (FSSS, 2011: http://www.gks.ru/dbscripts/Cbsd/DBInet.cgi#1). Among that, 91.75 mln ha is arable land; 92.05 mln ha - hayfield and pasture; 34.9 mln ha - abandoned arable and fallow. Abandoned arable area is not indicated directly in the statistics, but can be calculated as a difference between "arable" and "cultivated" area. We estimated carbon balance of agricultural land by accounting carbon fluxes. Carbon sink includes: net primary productivity (NPP), applying fertilizes and liming. Carbon losses include soil respiration (SR), harvest and lateral flux. The initial data (cultivated area and harvest distribution by regions and crop) was derived from national agriculture statistics (FSSS, 2011). NPP was estimated via harvest and set of regression models. Average NPP for agricultural land was estimated at 435 g C m-2 (530 g C m-2 for crops). Soil respiration was calculated by a model (Mukhortova et. al., 1011: http://www.iiasa.ac.at/Research/FOR/forest_cdrom/Articles/Mukhortova_2011_IBFRA_SR.pdf) developed for Russia which is based on all available empirical data and accounted for climatic parameters, soil type and management practice. Average SR of agricultural land is 344 g C m-2 (372 g C m-2 for the cropland). We applied the IPCC method (National inventory, 2010; IPCC, 2006) for fertilizer and lateral fluxes assessment. The total carbon balance of agricultural land is almost in equilibrium (-0.04 t C ha-1) in spite of arable land is a carbon source (-0.84 t C ha-1). The highest sink (1.21 t C ha-1) is provided by abandoned land. Carbon fluxes vary substantially depending on seasonal weather conditions. For example grains' NPP in 2010 (dry and hot summer in major agricultural regions of European Russia) was estimated at 32% less compare to 2009 and the total carbon balance of this land category decreased by order of magnitude. We used Russian land cover (Schepaschenko et al

  9. Analysis of breast milk to assess exposure to chlorinated contaminants in Kazakhstan: sources of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposures in an agricultural region of southern Kazakhstan.

    PubMed

    Hooper, K; Chuvakova, T; Kazbekova, G; Hayward, D; Tulenova, A; Petreas, M X; Wade, T J; Benedict, K; Cheng, Y Y; Grassman, J

    1999-06-01

    High levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; up to 208 pg/g fat) were measured in samples of breast milk collected in 1997 from 64 donors [41 first-time mothers (primiparae)] living on state farms in southern Kazakhstan. TCDD was the major contributor (70%) to the toxic equivalents, matching the congener patterns found in breast milk and serum samples collected in 1994 and 1996 from donors in nearby villages. The highest TCDD levels were found in state farms adjacent to a reservoir (zone A), which receives agricultural runoff from cotton fields. TCDD levels in zone A were significantly higher than levels in a region more distant (zone B; > 10 miles) from the reservoir (zone A: mean 53 pg/g, n = 17; zone B: mean 21 pg/g, n = 24; p = 0.0017). Levels of TCDD in breast milk and animal-derived foodstuffs were 10 times U.S. levels. Body burden and dietary data suggest that exposures to TCDD are chronic, environmental, and long term and may be related to the use of chemicals in cotton agriculture. The data suggest that the most likely source is the use of cotton defoliants contaminated with TCDD, and the most likely pathway for human exposure is via the consumption of contaminated foodstuffs.

  10. Analysis of breast milk to assess exposure to chlorinated contaminants in Kazakhstan: sources of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposures in an agricultural region of southern Kazakhstan.

    PubMed Central

    Hooper, K; Chuvakova, T; Kazbekova, G; Hayward, D; Tulenova, A; Petreas, M X; Wade, T J; Benedict, K; Cheng, Y Y; Grassman, J

    1999-01-01

    High levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; up to 208 pg/g fat) were measured in samples of breast milk collected in 1997 from 64 donors [41 first-time mothers (primiparae)] living on state farms in southern Kazakhstan. TCDD was the major contributor (70%) to the toxic equivalents, matching the congener patterns found in breast milk and serum samples collected in 1994 and 1996 from donors in nearby villages. The highest TCDD levels were found in state farms adjacent to a reservoir (zone A), which receives agricultural runoff from cotton fields. TCDD levels in zone A were significantly higher than levels in a region more distant (zone B; > 10 miles) from the reservoir (zone A: mean 53 pg/g, n = 17; zone B: mean 21 pg/g, n = 24; p = 0.0017). Levels of TCDD in breast milk and animal-derived foodstuffs were 10 times U.S. levels. Body burden and dietary data suggest that exposures to TCDD are chronic, environmental, and long term and may be related to the use of chemicals in cotton agriculture. The data suggest that the most likely source is the use of cotton defoliants contaminated with TCDD, and the most likely pathway for human exposure is via the consumption of contaminated foodstuffs. Images Figure 1 Figure 2 Figure 3 PMID:10515712

  11. Theme: Agricultural Educators in Non-School Settings.

    ERIC Educational Resources Information Center

    Mannebach, Alfred J.; And Others

    1993-01-01

    Four theme articles illustrate other settings for agriculture teachers besides public schools, including agriculture lobbying, children's home, preschool, exporting business, utilities industry, and youth group. (SK)

  12. 7 CFR 2.68 - Administrator, National Agricultural Statistics Service.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... promote and support the development of a viable and sustainable global agricultural system. Such work may... committees concerned with agricultural science, education, and development activities, including library...

  13. 7 CFR 2.68 - Administrator, National Agricultural Statistics Service.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... promote and support the development of a viable and sustainable global agricultural system. Such work may... committees concerned with agricultural science, education, and development activities, including library...

  14. U.S.-State Agricultural Data. Agriculture Information Bulletin Number 501.

    ERIC Educational Resources Information Center

    Womack, Letricia M.; And Others

    This report presents agricultural information for each of the 50 states and the United States. Data are provided on population, land use, agricultural production, farm income, value of assets on farms, and selected characteristics of farms, such as size, tenure, and farm organization. Primary data sources are the 1982 Census of Agriculture and the…

  15. [Multivariate geostatistics and GIS-based approach to study the spatial distribution and sources of heavy metals in agricultural soil in the Pearl River Delta, China].

    PubMed

    Cai, Li-mei; Ma, Jin; Zhou, Yong-zhang; Huang, Lan-chun; Dou, Lei; Zhang, Cheng-bo; Fu, Shan-ming

    2008-12-01

    One hundred and eighteen surface soil samples were collected from the Dongguan City, and analyzed for concentration of Cu, Zn, Ni, Cr, Pb, Cd, As, Hg, pH and OM. The spatial distribution and sources of soil heavy metals were studied using multivariate geostatistical methods and GIS technique. The results indicated concentrations of Cu, Zn, Ni, Pb, Cd and Hg were beyond the soil background content in Guangdong province, and especially concentrations of Pb, Cd and Hg were greatly beyond the content. The results of factor analysis group Cu, Zn, Ni, Cr and As in Factor 1, Pb and Hg in Factor 2 and Cd in Factor 3. The spatial maps based on geostatistical analysis show definite association of Factor 1 with the soil parent material, Factor 2 was mainly affected by industries. The spatial distribution of Factor 3 was attributed to anthropogenic influence. PMID:19256391

  16. Agricultural Education in the People's Republic of China.

    ERIC Educational Resources Information Center

    Henderson, Janet L.; He, Changxia

    1987-01-01

    Describes the system of agricultural education in the People's Republic of China. Topics include (1) the modernization of Chinese agriculture, (2) policy issues, (3) types of vocational agriculture schools, and (4) needs for the future. (CH)

  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. Cropland sources of water pollution

    SciTech Connect

    Peskin, H.M.

    1986-05-01

    In recent years, there has been a growing perception that the original objectives of the Clean Water Act would not be realized until more attention was directed toward so-called nonpoint sources of water pollution. These sources included run-off from city streets, rangelands, pastures, forests, croplands, and stream-bank erosion. Water pollution from the erosion of croplands has been a concern of the EPA and the Department of Agriculture for several years. This paper discussed the problem of cropland erosion as a source of water pollution and the potential effectiveness of legislation drafted to control this problem.

  19. Developments in greenhouse gas emissions and net energy use in Danish agriculture - how to achieve substantial CO(2) reductions?

    PubMed

    Dalgaard, T; Olesen, J E; Petersen, S O; Petersen, B M; Jørgensen, U; Kristensen, T; Hutchings, N J; Gyldenkærne, S; Hermansen, J E

    2011-11-01

    Greenhouse gas (GHG) emissions from agriculture are a significant contributor to total Danish emissions. Consequently, much effort is currently given to the exploration of potential strategies to reduce agricultural emissions. This paper presents results from a study estimating agricultural GHG emissions in the form of methane, nitrous oxide and carbon dioxide (including carbon sources and sinks, and the impact of energy consumption/bioenergy production) from Danish agriculture in the years 1990-2010. An analysis of possible measures to reduce the GHG emissions indicated that a 50-70% reduction of agricultural emissions by 2050 relative to 1990 is achievable, including mitigation measures in relation to the handling of manure and fertilisers, optimization of animal feeding, cropping practices, and land use changes with more organic farming, afforestation and energy crops. In addition, the bioenergy production may be increased significantly without reducing the food production, whereby Danish agriculture could achieve a positive energy balance.

  20. Sediment P in Agricultural Streams: Response to Land Use and Influence on TP Export

    NASA Astrophysics Data System (ADS)

    Rosamond, Madeline; Mohamed, Mohamed; Taylor, William

    2015-04-01

    Phosphorus export from agricultural streams can be a significant source to downstream water bodies, contributing to eutrophication, algal blooms and hypoxia. Sediment in agricultural streams can have very high P concentrations and has been proposed as a significant source of P to the water column though bioavailability can be low. Recent work suggests that sediments can sorb P from point sources such as WWTPs, and release this P during disturbances such as high flow events. However, it is unclear if sediment P responds to increased P application to the landscape, or if it is a significant source of P to annual TP export from agricultural streams. We examined 15 streams in southern Ontario, Canada, in highly agricultural catchments, comparing stream sediment P concentration to sediment geochemistry, P application, runoff, tile drainage, water column TP concentration and TP export. Stream sediment P was well correlated to sediment Fe and C and to tile drainage, and weakly correlated to manure P. This could suggest that sediment P responds to P addition, and may temporarily store P incoming from agricultural sources. Annual TP export was not correlated to stream sediment P concentration but was well correlated with runoff and tile drainage. This suggests P stored in sediment is a minor contributor to annual TP export. Effective agricultural P management strategies include implementing drainage water management, buffer zones etc. in catchments with high runoff and tile drainage.

  1. Agricultural chemistry and bioenergy.

    PubMed

    Orts, William J; Holtman, Kevin M; Seiber, James N

    2008-06-11

    Renewed interest in converting biomass to biofuels such as ethanol, other forms of bioenergy, and bioenergy byproducts or coproducts of commercial value opens opportunities for chemists, including agricultural chemists and related disciplines. Applications include feedstock characterization and quantification of structural changes resulting from genetic modification and of the intermediates formed during enzymatic and chemical processing; development of improved processes for utilizing chemical coproducts such as lactic acid and glycerol; development of alternative biofuels such as methanol, butanol, and hydrogen; and ways to reduce greenhouse gas emission and/or use carbon dioxide beneficially. Chemists will also be heavily involved in detailing the phytochemical composition of alternative energy crops and genetically improved crops. A resurgence of demand for agricultural chemistry and related disciplines argues for increasing output through targeted programs and on-the-job training. PMID:18473470

  2. 34 CFR 303.15 - Include; including.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Include; including. 303.15 Section 303.15 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF SPECIAL EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION EARLY INTERVENTION PROGRAM FOR INFANTS AND TODDLERS...

  3. Entomophagy and space agriculture

    NASA Astrophysics Data System (ADS)

    Katayama, N.; Ishikawa, Y.; Takaoki, M.; Yamashita, M.; Nakayama, S.; Kiguchi, K.; Kok, R.; Wada, H.; Mitsuhashi, J.; Space Agriculture Task Force, J.

    Supplying food for human occupants remains one of the primary issues in engineering space habitation Evidently for long-term occupation on a distant planet it is necessary to start agriculture on site Historically humans have consumed a variety of animals and it is required to fill our nutritional need when they live in space Among many candidate group and species of animal to breed in space agriculture insects are of great interest since they have a number of advantages over mammals and other vertebrates or invertebrates About 70-75 of animal species is insects and they play an important role in materials recycle loop of terrestrial biosphere at their various niche For space agriculture we propose several insect species such as the silkworm Bombyx mori the drugstore beetle Stegobium paniceum and the termite Macrotermes subhyalinus Among many advantages these insects do not compete with human in terms of food resources but convert inedible biomass or waste into an edible food source for human The silkworm has been domesticated since 5 000 years ago in China Silk moth has lost capability of flying after its domestication history This feature is advantageous in control of their breeding Silkworm larvae eat specifically mulberry leaves and metamorphose in their cocoon Silk fiber obtained from cocoon can be used to manufacture textile Farming system of the drugstore beetle has been well established Both the drugstore beetle and the termite are capable to convert cellulose or other inedible biomass

  4. Nonpoint Source Pollution.

    PubMed

    Mccoy, Nicholas; Chao, Bing; Gang, Daniel Dianchen

    2015-10-01

    The article presents a comprehensive review of research advancing in 2014 on nonpoint source pollution (NPS). The topics presented relate to nonpoint source pollution (NPS) within agricultural and urban areas. NPS pollution from agricultural areas is the main focus in this review. Management of NPS in agricultural, urban and rural areas is presented. Modeling of NPS pollution in different watersheds with various modeling tools is reviewed.

  5. Collaboration between Science and Agriculture Teachers

    ERIC Educational Resources Information Center

    Stephenson, Lee G.; Warnick, Brian K.; Tarpley, Rudy S.

    2008-01-01

    The focus of this descriptive study was to determine the type and frequency of collaborative activities occurring between agriculture teachers and science teachers who taught in schools with agricultural education programs. Additional foci of this study included determining the extent to which science and agriculture teachers value collaborative…

  6. Theme: Teaching Physical Science Applications in Agriculture.

    ERIC Educational Resources Information Center

    Osborne, Edward W.; And Others

    1996-01-01

    Includes "Preparing Teachers to Teach Agriscience" (Osborne); "Physical Sciences and Agriculture" (Buriak); "Using Experiments to Teach Agriculture" (Miller); "Oooh-Ahhh: So That's How It Works!" (Loschen); "Keeping Agriculture in Agriscience" (Moss); "Sharpening Twist Drills" (McHargue, Hood); and "Safety in the Agriscience Laboratory"…

  7. Agricultural Mechanics: Program Planning Guide: Volume 3.

    ERIC Educational Resources Information Center

    Bristol, Benton K.

    The program planning guide for agricultural mechanics was written to assist Applied Biological and Agricultural Occupations (ABAO) teachers in enriching existing programs and/or to provide the basis for expansion of offerings to include additional materials for the cluster areas of agricultural power and machinery, structural and conveniences,…

  8. Agriculture and climate change

    SciTech Connect

    Abelson, P.H.

    1992-07-03

    How will increases in levels of CO{sub 2} and changes in temperature affect food production A recently issued report analyzes prospects for US agriculture 1990 to 2030. The report, prepared by a distinguished Task Force, first projects the evolution of agriculture assuming increased levels of CO{sub 2} but no climate change. Then it deals with effects of climate change, followed by a discussion of how greenhouse emissions might be diminished by agriculture. Economic and policy matters are also covered. How the climate would respond to more greenhouse gases is uncertain. If temperatures were higher, there would be more evaporation and more precipitation. Where would the rain fall That is a good question. Weather in a particular locality is not determined by global averages. The Dust Bowl of the 1930s could be repeated at its former site or located in another region such as the present Corn Belt. But depending on the realities at a given place, farmers have demonstrated great flexibility in choosing what they may grow. Their flexibility has been increased by the numerous varieties of seeds of major crops that are now available, each having different characteristics such as drought resistance and temperature tolerance. In past, agriculture has contributed about 5% of US greenhouse gases. Two large components have involved emissions of CO{sub 2} from farm machinery and from oxidation of organic matter in soil due to tillage. Use of diesel fuel and more efficient machinery has reduced emissions from that source by 40%. In some areas changed tillage practices are now responsible for returning carbon to the soil. The report identifies an important potential for diminishing net US emissions of CO{sub 2} by growth and utilization of biomass. Large areas are already available that could be devoted to energy crops.

  9. Programs in Animal Agriculture.

    ERIC Educational Resources Information Center

    Herring, Don R.; And Others

    1980-01-01

    Five topics relating to programs in animal agriculture are addressed: (1) the future of animal agriculture; (2) preparing teachers in animal agriculture; (3) how animal programs help young people; (4) a nontraditional animal agriculture program; and (5) developing competencies in animal agriculture. (LRA)

  10. Grower Communication Networks: Information Sources for Organic Farmers

    ERIC Educational Resources Information Center

    Crawford, Chelsi; Grossman, Julie; Warren, Sarah T.; Cubbage, Fred

    2015-01-01

    This article reports on a study to determine which information sources organic growers use to inform farming practices by conducting in-depth semi-structured interviews with 23 organic farmers across 17 North Carolina counties. Effective information sources included: networking, agricultural organizations, universities, conferences, Extension, Web…

  11. Importance of including small body spin effects in the modelling of intermediate mass-ratio inspirals. II. Accurate parameter extraction of strong sources using higher-order spin effects

    NASA Astrophysics Data System (ADS)

    Huerta, E. A.; Gair, Jonathan R.; Brown, Duncan A.

    2012-03-01

    We improve the numerical kludge waveform model introduced in Huerta and Gair (2011) [E. A. Huerta and J. R. Gair, Phys. Rev. D 84, 064023 (2011).PRVDAQ1550-799810.1103/PhysRevD.84.064023] in two ways. We extend the equations of motion for spinning black hole binaries derived by Saijo et al. [M. Saijo, K. Maeda, M. Shibata, and Y. Mino, Phys. Rev. D 58, 064005 (1998).PRVDAQ0556-282110.1103/PhysRevD.58.064005] using spin-orbit and spin-spin couplings taken from perturbative and post-Newtonian (PN) calculations at the highest order available. We also include first-order conservative self-force corrections for spin-orbit and spin-spin couplings, which are derived by comparison to PN results. We generate the inspiral evolution using fluxes that include the most recent calculations of small body spin corrections, spin-spin, and spin-orbit couplings and higher-order fits to solutions of the Teukolsky equation. Using a simplified version of this model in [E. A. Huerta and J. R. Gair, Phys. Rev. D 84, 064023 (2011).PRVDAQ1550-799810.1103/PhysRevD.84.064023], we found that small body spin effects could be measured through gravitational-wave observations from intermediate-mass-ratio inspirals (IMRIs) with mass ratio η≳10-3, when both binary components are rapidly rotating. In this paper, we present results of Monte Carlo simulations of parameter-estimation errors to study in detail how the spin of the small/big body affects parameter measurement using a variety of mass and spin combinations for typical IMRI sources. We have found that for IMRI events involving a moderately rotating intermediate-mass black hole (IMBH) of mass 104M⊙ and a rapidly rotating central supermassive black hole (SMBH) of mass 106M⊙, gravitational wave observations made with LISA at a signal-to-noise ratio of 1000 should be able to determine the inspiralling IMBH mass, the central SMBH mass, the SMBH spin magnitude, and the IMBH spin magnitude to within fractional errors of ˜10-3, 10-3, 10

  12. Agricultural Extension: Who Uses It?

    ERIC Educational Resources Information Center

    Nolan, Michael; Lasley, Paul

    1979-01-01

    A Missouri study conducted to determine agricultural extension usage patterns found that heavy users of extension publications tended to be younger farmers, those with a relatively large amount of land, and pork producers. Extension meetings were a less frequent source of information than either publications or county extension office visits. (LRA)

  13. Innovation and Teaching in Agriculture.

    ERIC Educational Resources Information Center

    Nieuwenhuis, Loek F. M.

    2002-01-01

    Two case studies were conducted: (1) linear innovation through technology diffusion in Dutch agriculture and (2) knowledge sources and learning processes of Dutch farmer- entrepreneurs. Learning and innovation were central to entrepreneurship. Innovative learning involved balancing the chaos of uncertainty and the status quo of experience.…

  14. Application of methane fermentation technology into organic wastes in closed agricultural system

    NASA Astrophysics Data System (ADS)

    Endo, Ryosuke; Kitaya, Yoshiaki

    Sustainable and recycling-based systems are required in space agriculture which takes place in an enclosed environment. Methane fermentation is one of the most major biomass conversion technologies, because (1) it provides a renewable energy source as biogas including methane, suitable for energy production, (2) the nutrient-rich solids left after digestion can be used as compost for agriculture. In this study, the effect of the application of methane fermentation technology into space agriculture on the material and energy cycle was investigated.

  15. Agricultural Education: Key to Providing Broader Opportunities for Third World Women in Production Agriculture.

    ERIC Educational Resources Information Center

    Lelle, Mark A.; Holt, Barbara A.

    1987-01-01

    The authors focus on providing opportunities for women in Third World countries in agriculture. A review of the body of knowledge in agricultural development and of the issues surrounding current world food crises is included. (CH)

  16. Peruvian Arid Coast and Agriculture, South America

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The coast of Peru, between the Pacific Ocean and the Andes Mountains is very arid (16.5S, 72.5W). For several thousand years, water from numerous small streams has been used for traditional flood and canal irrigation agriculture. However, during the past decade innovative techniques have tapped new water sources for increased agricultural production. Ground water in the porous sedimentary rock formations has been tapped for well irrigation agriculture.

  17. Agricultural Education at Risk.

    ERIC Educational Resources Information Center

    Evans, Donald E.

    1988-01-01

    Discusses educational reform in the context of agricultural education. Covers a recent report on agricultural education reform by the National Academy of Sciences, state legislative initiatives, and several recommendations for the future of agricultural education. (CH)

  18. Review of ammonia emission factors for United States animal agriculture

    NASA Astrophysics Data System (ADS)

    Faulkner, W. B.; Shaw, B. W.

    Ammonia emissions from agricultural industries are a significant source of atmospheric reactive nitrogen, which can lead to negative environmental consequences such as ecosystem change and formation of fine particulate. While a number of emission factors (EFs) have been proposed for developing ammonia emissions inventories for the US, most are based on European research with little discussion of their applicability to US production systems. Recently developed ammonia EFs from literature for animal feeding operations (AFOs), including production facilities for beef and dairy cattle, swine, and poultry, are presented. Tentative EFs for US animal agriculture are suggested until further research can be conducted. Currently, there is a dearth of EFs developed specifically for agricultural production practices in the US.

  19. Interactions of U.S. Agricultural Production with Climatic Stresses and Reactive Nitrogen

    NASA Astrophysics Data System (ADS)

    Gehl, R. J.; Robertson, G. P.; Bruulsema, T. W.; Kanter, D.; Mauzerall, D. L.; Rotz, C. A.; Williams, C. O.

    2011-12-01

    Agricultural production both contributes to and responds to climatic variations across spatial and temporal continuums. The agriculture sector is responsible for over 6% of total U.S. greenhouse gas emissions, primarily as methane (CH4) and nitrous oxide (N2O) gases emitted by agricultural activities. Agriculture activities specifically account for about 69% of U.S. N2O emissions, largely as a result of production practices including fertilizer management, cropping systems, and manure management. Fertilizers, together with manure and legume fixation, are the three main inputs of N to US agricultural soils. All three sources have been increasing over the past two decades, while the rate at which they are removed in the form of harvested crops has been increasing at a slightly slower rate. The outlook for continued large areas of cultivation in the U.S., specifically for corn production and supported by biofuel production goals, is a major factor in sustaining demand for N fertilizer. However, rising fertilizer prices and environmental pressures on producers are encouraging increased adoption of emerging technologies such as precision agriculture, cultivars with higher N use efficiency, and enhanced-efficiency N sources such as controlled-release forms or forms with urease or nitrification inhibitors. Crop productivity also responds to climatic changes, as crop growth is affected by variables including heat, drought, ozone (O3), and increased ambient carbon dioxide (CO2). We summarize sources and fates of N for cropping systems and intensive animal systems and assess how climate change will affect crop response to and recovery of N and subsequent cascading effects on Nr. The complex interactions between agricultural Nr and climate present opportunities for mitigation/adaption relative to N use. N fertilizer and manure management, tillage, technology, and decision support models provide significant opportunities for climate mitigation and adaption in U.S. agriculture

  20. Perceived agricultural runoff impact on drinking water.

    PubMed

    Crampton, Andrea; Ragusa, Angela T

    2014-09-01

    Agricultural runoff into surface water is a problem in Australia, as it is in arguably all agriculturally active countries. While farm practices and resource management measures are employed to reduce downstream effects, they are often either technically insufficient or practically unsustainable. Therefore, consumers may still be exposed to agrichemicals whenever they turn on the tap. For rural residents surrounded by agriculture, the link between agriculture and water quality is easy to make and thus informed decisions about water consumption are possible. Urban residents, however, are removed from agricultural activity and indeed drinking water sources. Urban and rural residents were interviewed to identify perceptions of agriculture's impact on drinking water. Rural residents thought agriculture could impact their water quality and, in many cases, actively avoided it, often preferring tank to surface water sources. Urban residents generally did not perceive agriculture to pose health risks to their drinking water. Although there are more agricultural contaminants recognised in the latest Australian Drinking Water Guidelines than previously, we argue this is insufficient to enhance consumer protection. Health authorities may better serve the public by improving their proactivity and providing communities and water utilities with the capacity to effectively monitor and address agricultural runoff.

  1. The Land Grant Colleges of Agriculture.

    ERIC Educational Resources Information Center

    Campbell, Rex R.

    1991-01-01

    Discusses the following alternatives for the colleges of agriculture: (1) continue the status quo; (2) specialize to serve the needs of a group not currently served by traditional colleges of agriculture; or (3) reduce the dependence on traditional clientele groups through more funding with grants from industries or governmental sources. Provides…

  2. Nitrate concentrations and fluxes in the River Thames, London UK 1868 to 2008: catchment-scale modelling of diffuse agricultural sources and groundwater response using the world's longest water quality time series

    NASA Astrophysics Data System (ADS)

    Howden, N. J.; Burt, T. P.; Worrall, F.; Mathias, S.; Whelan, M.

    2011-12-01

    This paper presents analyses of the world's longest water quality record: 140 years of monthly-average nitrate concentrations (1868 to 2008) and fluxes (1883 to 2008) for the River Thames north of London. We show how short- and long- term patterns in these time series are influenced by both climatic and anthropogenic pressures, in the case of the latter, particularly land use and land management practices. Climate change does not play a significant role in controlling annual average concentrations or fluxes, rather large-scale land conversions from permanent grassland to arable farming have created sustained diffuse sources of nitrate that have caused (almost four-fold) increases in concentrations and fluxes that persist for many decades after the initial changes. Our analyses of this unique time series highlight four areas of particular interest: (1) Despite several layers of regulation and source control, fluvial concentrations and fluxes remain in- tractably high - no decrease has been observed since the early 1970s; (2) Catchment response to changing nitrogen inputs from land use and land management is subject to considerable lag: present conditions in the river reflect land practices from some years ago; (3) Following (2), we suggest that current changes to land use and land management practices will not be reflected in river water quality for some time to come; (4) Overall, the long-term view afforded by this record questions the derivation of "baseline conditions" that are formulated from records that do not reflect the massive changes in land use and land management in the mid-20th century. Overall, a better understanding of the links, and time delays, between cause (i.e. changing land use / land management) and fluvial response (i.e. concentration increase/decrease) will improve our ability both to predict changes in the coming decades, and inform management decision making now, to ensure the appropriate balance between agricultural development and

  3. Comparison of organic matter composition in agricultural versus forest affected headwaters with special emphasis on organic nitrogen.

    PubMed

    Heinz, Marlen; Graeber, Daniel; Zak, Dominik; Zwirnmann, Elke; Gelbrecht, Joerg; Pusch, Martin T

    2015-02-17

    Agricultural management practices promote organic matter (OM) turnover and thus alter both the processing of dissolved organic matter (DOM) in soils and presumably also the export of DOM to headwater streams, which intimately connect the terrestrial with the aquatic environment. Size-exclusion chromatography, in combination with absorbance and emission matrix fluorometry, was applied to assess how agricultural land use alters the amount and composition of DOM, as well as dissolved organic nitrogen (DON) forms in headwater streams, including temporal variations, in a temperate region of NE Germany. By comparing six agriculturally and six forest-impacted headwater streams, we demonstrated that agriculture promotes increased DOC and DON concentrations, entailing an even more pronounced effect on DON. The major part of DOC and DON in agricultural and forest reference streams is exported in the form of humic-like material with high molecular weight, which indicates terrestrial, i.e., allochthonous sources. As an obvious difference in agricultural streams, the contribution of DOC and particularly DON occurring in the form of nonhumic high-molecular-weight, presumably proteinous material is clearly elevated. Altogether, DOM in agricultural headwaters is mainly complex-soil-derived and aromatic material with a low C:N ratio, which is more microbial processed than its counterpart from forest reference catchments. Our results emphasize the importance of agricultural land use on DOM loss from soils and identify agricultural soils as important DOC and particularly DON sources to headwater streams. PMID:25594834

  4. Biotic stress resistance in agriculture through antimicrobial peptides.

    PubMed

    Sarika; Iquebal, M A; Rai, Anil

    2012-08-01

    Antimicrobial peptides (AMPs) are the hosts' defense molecules against microbial pathogens and gaining extensive research attention worldwide. These have been reported to play vital role of host innate immunity in response to microbial challenges. AMPs can be used as a natural antibiotic as an alternative of their chemical counterpart for protection of plants/animals against diseases. There are a number of sources of AMPs including prokaryotic and eukaryotic organisms and are present, both in vertebrates and invertebrates. AMPs can be classified as cationic or anionic, based on net charges. Large number of databases and tools are available in the public domain which can be used for development of new genetically modified disease resistant varieties/breeds for agricultural production. The results of the biotechnological research as well as genetic engineering related to AMPs have shown high potential for reduction of economic losses of agricultural produce due to pathogens. In this article, an attempt has been made to introduce the role of AMPs in relation to plants and animals. Their functional and structural characteristics have been described in terms of its role in agriculture. Different sources of AMPs and importance of these sources has been reviewed in terms of its availability. This article also reviews the bioinformatics resources including different database tools and algorithms available in public domain. References of promising biotechnology research in relation to AMPs, prospects of AMPs for further development of genetically modified varieties/breeds are highlighted. AMPs are valuable resource for students, researchers, educators and medical and industrial personnel.

  5. Origin and Development of Industrial Education at Alcorn Agricultural and Mechanical College.

    ERIC Educational Resources Information Center

    Smith, Jay T.

    This study covering the last 100 years in the development of industrial education at Alcorn Agricultural and Mechanical College was prompted by the need to determine the role of the college in the development of industrial education in the state of Mississippi. Sources of data included college catalogs, reports of the college administration and…

  6. The links between agriculture and health: an intersectoral opportunity to improve the health and livelihoods of the poor.

    PubMed

    Hawkes, Corinna; Ruel, Marie

    2006-12-01

    Agriculture and health are linked in many ways. First, agriculture is essential for good health: it produces the world's food, fibre and materials for shelter; in many countries it is also an important source of livelihood among the poor. At the same time, agriculture can be linked with poor health, including malnutrition, malaria, foodborne illnesses, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), livestock-related diseases, chronic diseases and occupational ill-health. Health also affects agriculture: people's health status influences the demand for agricultural outputs, and in agricultural communities, poor health reduces work performance, reducing income and productivity and perpetuating a downward spiral into ill-health. This paper presents an overview of the bidirectional links between agriculture and health with a focus on the developing world. It develops a conceptual framework that brings together the various links between agriculture and health into a single broad framework. The framework comprises the core components of the agricultural supply chain (producers, systems and outputs), key health concerns and the mechanisms of common interaction between the agricultural and health components: income, labour, environment and access -- all key social determinants of health. These links between agriculture and health present an opportunity for the two sectors to work together to find solutions to each other's problems. Yet the health and agricultural sectors remain poorly coordinated. Leadership from global health and agricultural institutions is needed to build policies and good governance to facilitate integration, while capacity building is needed at all levels to help translate the conceptual links into comprehensive action on the ground. Health and agricultural researchers likewise need to work more closely together to achieve common goals. PMID:17242835

  7. The links between agriculture and health: an intersectoral opportunity to improve the health and livelihoods of the poor.

    PubMed Central

    Hawkes, Corinna; Ruel, Marie

    2006-01-01

    Agriculture and health are linked in many ways. First, agriculture is essential for good health: it produces the world's food, fibre and materials for shelter; in many countries it is also an important source of livelihood among the poor. At the same time, agriculture can be linked with poor health, including malnutrition, malaria, foodborne illnesses, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), livestock-related diseases, chronic diseases and occupational ill-health. Health also affects agriculture: people's health status influences the demand for agricultural outputs, and in agricultural communities, poor health reduces work performance, reducing income and productivity and perpetuating a downward spiral into ill-health. This paper presents an overview of the bidirectional links between agriculture and health with a focus on the developing world. It develops a conceptual framework that brings together the various links between agriculture and health into a single broad framework. The framework comprises the core components of the agricultural supply chain (producers, systems and outputs), key health concerns and the mechanisms of common interaction between the agricultural and health components: income, labour, environment and access -- all key social determinants of health. These links between agriculture and health present an opportunity for the two sectors to work together to find solutions to each other's problems. Yet the health and agricultural sectors remain poorly coordinated. Leadership from global health and agricultural institutions is needed to build policies and good governance to facilitate integration, while capacity building is needed at all levels to help translate the conceptual links into comprehensive action on the ground. Health and agricultural researchers likewise need to work more closely together to achieve common goals. PMID:17242835

  8. The links between agriculture and health: an intersectoral opportunity to improve the health and livelihoods of the poor.

    PubMed

    Hawkes, Corinna; Ruel, Marie

    2006-12-01

    Agriculture and health are linked in many ways. First, agriculture is essential for good health: it produces the world's food, fibre and materials for shelter; in many countries it is also an important source of livelihood among the poor. At the same time, agriculture can be linked with poor health, including malnutrition, malaria, foodborne illnesses, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), livestock-related diseases, chronic diseases and occupational ill-health. Health also affects agriculture: people's health status influences the demand for agricultural outputs, and in agricultural communities, poor health reduces work performance, reducing income and productivity and perpetuating a downward spiral into ill-health. This paper presents an overview of the bidirectional links between agriculture and health with a focus on the developing world. It develops a conceptual framework that brings together the various links between agriculture and health into a single broad framework. The framework comprises the core components of the agricultural supply chain (producers, systems and outputs), key health concerns and the mechanisms of common interaction between the agricultural and health components: income, labour, environment and access -- all key social determinants of health. These links between agriculture and health present an opportunity for the two sectors to work together to find solutions to each other's problems. Yet the health and agricultural sectors remain poorly coordinated. Leadership from global health and agricultural institutions is needed to build policies and good governance to facilitate integration, while capacity building is needed at all levels to help translate the conceptual links into comprehensive action on the ground. Health and agricultural researchers likewise need to work more closely together to achieve common goals.

  9. Agricultural opportunities to mitigate greenhouse gas emissions.

    PubMed

    Johnson, Jane M-F; Franzluebbers, Alan J; Weyers, Sharon Lachnicht; Reicosky, Donald C

    2007-11-01

    Agriculture is a source for three primary greenhouse gases (GHGs): CO(2), CH(4), and N(2)O. It can also be a sink for CO(2) through C sequestration into biomass products and soil organic matter. We summarized the literature on GHG emissions and C sequestration, providing a perspective on how agriculture can reduce its GHG burden and how it can help to mitigate GHG emissions through conservation measures. Impacts of agricultural practices and systems on GHG emission are reviewed and potential trade-offs among potential mitigation options are discussed. Conservation practices that help prevent soil erosion, may also sequester soil C and enhance CH(4) consumption. Managing N to match crop needs can reduce N(2)O emission and avoid adverse impacts on water quality. Manipulating animal diet and manure management can reduce CH(4) and N(2)O emission from animal agriculture. All segments of agriculture have management options that can reduce agriculture's environmental footprint.

  10. Agriculture as a subject in primary school

    NASA Astrophysics Data System (ADS)

    Bergmann, Herbert

    1985-12-01

    Many countries have included agriculture as a subject in primary school for a number of reasons. The present article briefly presents five rationales for including agriculture and offers three main approaches which seem to emerge from current practice. The main results of the subsequent discussion can be summarized as follows: integrating education with rural development most of the time would mean including agriculture as a subject in primary schools in rural areas and compensating it in core curriculum with some sort of practical subject taught in urban areas. It becomes clear that narrow vocational and extension-support approaches to school agriculture should be avoided in favour of a more general approach which relates agriculture to science. Unless these problems — curricular, technical, and organizational — are tackled, the results of school agriculture and its acceptance by those concerned will remain far behind expectations and possibilities.

  11. Drought, Climate Change and Potential Agricultural Productivity

    NASA Astrophysics Data System (ADS)

    Sheffield, J.; Herrera-Estrada, J. E.; Caylor, K. K.; Wood, E. F.

    2011-12-01

    Drought is a major factor in agricultural productivity, especially in developing regions where the capacity for water resources management is limited and climate variability ensures that drought is recurrent and problematic. Recent events in East Africa are testament to this, where drought conditions that have slowly developed over multiple years have contributed to reduced productivity and ultimately food crises and famine. Prospects for the future are not promising given ongoing problems of dwindling water supplies from non-renewable sources and the potential for increased water scarcity and increased drought with climate change. This is set against the expected increase in population by over 2 billion people by 2050 and rise in food demand, coupled with changes in demographics that affect food choices and increases in non-food agriculture. In this talk we discuss the global variability of drought over the 20th century and recent years, and the projected changes over the 21st century, and how this translates into changes in potential agricultural productivity. Drought is quantified using land surface hydrological models driven by a hybrid reanalysis-observational meteorological forcing dataset. Drought is defined in terms of anomalies of hydroclimatic variables, in particular precipitation, evaporation and soil moisture, and we calculate changes in various drought characteristics. Potential agricultural productivity is derived from the balance of precipitation to crop water demand, where demand is based on potential evaporation and crop coefficients for a range of staple crops. Some regional examples are shown of historic variations in drought and potential productivity, and the estimated water deficit for various crops. The multitude of events over the past decade, including heat waves in Europe, fires in Russia, long-term drought in northern China, southeast Australia, the Western US and a series of droughts in the Amazon and Argentina, hint at the influence of

  12. Publisher Source Directory: A List of Where to Buy or Rent Instructional Materials and Other Educational Aids, Devices, and Media Including More Than 1,600 Publishers and Producers in the U.S., Canada, and Europe. Revised Edition.

    ERIC Educational Resources Information Center

    National Center on Educational Media and Materials for the Handicapped, Columbus, OH.

    Listed are more than 1,600 publishers, producers, and distributors of educational materials for use with the handicapped. Entries are presented in alphabetical order according to name. Beneath each source's name and address are code numbers which correspond to the type of materials each publisher's catalog lists. Provided is a list of the codes…

  13. Nitrogen-source regulation of yeast gamma-glutamyl transpeptidase synthesis involves the regulatory network including the GATA zinc-finger factors Gln3, Nil1/Gat1 and Gzf3.

    PubMed Central

    Springael, Jean-Yves; Penninckx, Michel J

    2003-01-01

    In Saccharomyces cerevisiae, the CIS2 gene encodes gamma-glutamyl transpeptidase (gamma-GT; EC 2.3.2.2), the main GSH-degrading enzyme. The promoter region of CIS2 contains one stress-response element (CCCCT) and eight GAT(T/A)A core sequences, probably involved in nitrogen-regulated transcription. We show in the present study that expression of CIS2 is indeed regulated according to the nature of the nitrogen source. Expression is highest in cells growing on a poor nitrogen source such as urea. Under these conditions, the GATA zinc-finger transcription factors Nil1 and Gln3 are both required for CIS2 expression, Nil1 appearing as the more important factor. We further show that Gzf3, another GATA zinc-finger protein, acts as a negative regulator in nitrogen-source control of CIS2 expression. During growth on a preferred nitrogen source like NH(4)(+), CIS2 expression is repressed through a mechanism involving (at least) the Gln3-binding protein Ure2/GdhCR. Induction of CIS2 expression during nitrogen starvation is dependent on Gln3 and Nil1. Furthermore, rapamycin causes similar CIS2 activation, indicating that the target of rapamycin signalling pathway controls CIS2 expression via Gln3 and Nil1 in nitrogen-starved cells. Finally, our results show that CIS2 expression is induced mainly by nitrogen starvation but apparently not by other types of stress. PMID:12529169

  14. Agriculture Supplies & Services. Volume 3 of 3.

    ERIC Educational Resources Information Center

    Kansas State Univ., Manhattan.

    The third of three volumes included in a secondary agricultural supplies and services curriculum guide, this volume contains twenty-five units of instruction in the area of agricultural mechanics. Among the unit topics included are (1) Farm Safety, (2) Ignition Systems; (3) Servicing Wheel Bearings, (4) Oxyacetylene Cutting, (5) Servicing the…

  15. Review, mapping and analysis of the agricultural plastic waste generation and consolidation in Europe.

    PubMed

    Briassoulis, Demetres; Babou, Epifania; Hiskakis, Miltiadis; Scarascia, Giacomo; Picuno, Pietro; Guarde, Dorleta; Dejean, Cyril

    2013-12-01

    A review of agricultural plastic waste generation and consolidation in Europe is presented. A detailed geographical mapping of the agricultural plastic use and waste generation in Europe was conducted focusing on areas of high concentration of agricultural plastics. Quantitative data and analysis of the agricultural plastic waste generation by category, geographical distribution and compositional range, and physical characteristics of the agricultural plastic waste per use and the temporal distribution of the waste generation are presented. Data were collected and cross-checked from a variety of sources, including European, national and regional services and organizations, local agronomists, retailers and farmers, importers and converters. Missing data were estimated indirectly based on the recorded cultivated areas and the characteristics of the agricultural plastics commonly used in the particular regions. The temporal distribution, the composition and physical characteristics of the agricultural plastic waste streams were mapped by category and by application. This study represents the first systematic effort to map and analyse agricultural plastic waste generation and consolidation in Europe.

  16. Occurrences and toxicological risk assessment of eight heavy metals in agricultural soils from Kenya, Eastern Africa.

    PubMed

    Mungai, Teresiah Muciku; Owino, Anita Awino; Makokha, Victorine Anyango; Gao, Yan; Yan, Xue; Wang, Jun

    2016-09-01

    The concentration distribution and toxicological assessment of eight heavy metals including lead (Pb), cadmium (Cd), copper (Cu), chromium (Cr), nickel (Ni), mercury (Hg), arsenic (As), and zinc (Zn) in agricultural soils from Kenya, Eastern Africa, were investigated in this study. The results showed mean concentrations of eight heavy metals of Zn, Pb, Cr, Cu, As, Ni, Hg, and Cd in agricultural soils as 247.39, 26.87, 59.69, 88.59, 8.93, 12.56, 8.06, and 0.42 mg kg(-1), respectively. These mean values of eight heavy metals were close to the toxicity threshold limit of USEPA standard values of agricultural soils, indicating potential toxicological risk to the food chain. Pollution index values revealed that eight heavy metals severely decreased in the order Hg > Cd > As > Cu > Pb > Zn > Ni > Cr and the mean value of the overall pollution index of Hg and Cd was 20.31, indicating severe agriculture ecological risk. Potential pollution sources of eight heavy metals in agricultural soils were mainly from anthropogenic activities and natural dissolution. The intensification of human agricultural activities, the growing industrialization, and the rapid urbanization largely influenced the concentration levels of heavy metals in Kenya, Eastern Africa. Moreover, the lack of agricultural normalization management and poor enforcement of environmental laws and regulations further intensified the widespread pollution of agricultural soils in Kenya. PMID:27291978

  17. Climate-smart agriculture for food security

    NASA Astrophysics Data System (ADS)

    Lipper, Leslie; Thornton, Philip; Campbell, Bruce M.; Baedeker, Tobias; Braimoh, Ademola; Bwalya, Martin; Caron, Patrick; Cattaneo, Andrea; Garrity, Dennis; Henry, Kevin; Hottle, Ryan; Jackson, Louise; Jarvis, Andrew; Kossam, Fred; Mann, Wendy; McCarthy, Nancy; Meybeck, Alexandre; Neufeldt, Henry; Remington, Tom; Sen, Pham Thi; Sessa, Reuben; Shula, Reynolds; Tibu, Austin; Torquebiau, Emmanuel F.

    2014-12-01

    Climate-smart agriculture (CSA) is an approach for transforming and reorienting agricultural systems to support food security under the new realities of climate change. Widespread changes in rainfall and temperature patterns threaten agricultural production and increase the vulnerability of people dependent on agriculture for their livelihoods, which includes most of the world's poor. Climate change disrupts food markets, posing population-wide risks to food supply. Threats can be reduced by increasing the adaptive capacity of farmers as well as increasing resilience and resource use efficiency in agricultural production systems. CSA promotes coordinated actions by farmers, researchers, private sector, civil society and policymakers towards climate-resilient pathways through four main action areas: (1) building evidence; (2) increasing local institutional effectiveness; (3) fostering coherence between climate and agricultural policies; and (4) linking climate and agricultural financing. CSA differs from 'business-as-usual' approaches by emphasizing the capacity to implement flexible, context-specific solutions, supported by innovative policy and financing actions.

  18. 1986 Agricultural Chartbook. Agriculture Handbook No. 663.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC.

    This book contains 310 charts, tables, and graphs containing statistical information about agriculture-related commodities and services, primarily in the United States, in 1986. The book is organized in seven sections that cover the following topics: (1) the farm (farm income, farm population, farm workers, food and fiber system, agriculture and…

  19. 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 ...

  20. Agricultural Chartbook 1988. Agriculture Handbook No. 673.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC.

    These charts present an overview of the current economic health of American agriculture. The charts move from the national and international arenas to farm economic health measures and crop and livestock trends. A small amount of descriptive narrative accompanies most of the charts. Charts depicting the economic picture of U.S. agriculture include…

  1. Composting of agricultural and industrial wastes. (Latest citations from the Compendex database). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning agricultural and industrial waste treatment by composting. Articles discuss techniques, source materials, end product uses, and cost effectiveness. Materials considered include sawdust, wood chips, straw, manures, produce wastes, and industrial waste sludges. Applications of end products include pressed containers, fertilizers and soil amendments, and topsoil replacement. Composting of municipal wastes and sewage wastes is referenced in a related bibliography. (Contains a minimum of 80 citations and includes a subject term index and title list.)

  2. Precision agriculture in the 21st Century: Geospatial and information technologies in crop management

    SciTech Connect

    1997-12-31

    Agricultural managers have for decades taken advantage of new technologies, including information technologies, that enabled better management decision making and improved economic efficiency of operations. The extent and rate of change now occurring in the development of information technologies have opened the way for significant change in crop production management and agricultural decision making. This vision is reflected in the concept of precision agriculture. Precision agriculture is a phrase that captures the imagination of many concerned with the production of food, feed, and fiber. The concepts embodied in precision agriculture offer the promise of increasing productivity while decreasing production costs and minimizing environmental impacts. Precision agriculture conjures up images of farmers overcoming the elements with computerized machinery that is precisely controlled via satellites and local sensors and using planning software that accurately predicts crop development. This image has been called the future of agriculture. Such high-tech images are engaging. Precision agriculture, however, is in early and rapidly changing phases of innovation. Techniques and practices not anticipated by the committee will likely become common in the future, and some techniques and practices thought to hold high promise today may turn out to be less desirable than anticipated. This report defines precision agriculture as a management strategy that uses information technologies to bring data from multiple sources to bear on decisions associated with crop production. Precision agriculture has three components: capture of data at an appropriate scale and frequency, interpretation and analysis of that data, and implementation of a management response at an appropriate scale and time. The most significant impact of precision agriculture is likely to be on how management decisions address spatial and temporal variability in crop production systems.

  3. Understanding Canadian Agriculture. "Understanding Economics" Series No. 5.

    ERIC Educational Resources Information Center

    Loyns, R. M. A.

    This document for secondary school Canadian students analyzes the role of agriculture in the national economy and in Canadian trade, describes characteristics of Canadian farms, and discusses governmental inlfuences on Canadian agriculture. The document stresses that agriculture is a large source of national wealth; about 30% of Canadian farm…

  4. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations...

  5. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations...

  6. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations...

  7. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations...

  8. 7 CFR 201.7 - Purity (including variety).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Records for Agricultural and Vegetable Seeds § 201.7 Purity (including variety). The complete record for any lot of seed shall include (a) records of analyses, tests, and examinations...

  9. Methylotrophic bacteria in sustainable agriculture.

    PubMed

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices.

  10. Weather extremes could affect agriculture

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-05-01

    As Earth's climate warms, agricultural producers will need to adapt. Changes, especially increases in extreme events, are already having an impact on food production, according to speakers at a 1 May session on agriculture and food security at the AGU Science Policy Conference. Christopher Field, director of the Department of Global Ecology at the Carnegie Institution for Science of Washington, D. C., pointed out the complex factors that come into play in understanding food security, including spatially varying controls and stresses, incomplete models, and the potential for threshold responses. Factors that are likely to cause problems include increasing population; increasing preference for meat, which needs more land and energy inputs to produce; climate change; and increasing use of agricultural lands for biomass energy.

  11. Methylotrophic bacteria in sustainable agriculture.

    PubMed

    Kumar, Manish; Tomar, Rajesh Singh; Lade, Harshad; Paul, Diby

    2016-07-01

    Excessive use of chemical fertilizers to increase production from available land has resulted in deterioration of soil quality. To prevent further soil deterioration, the use of methylotrophic bacteria that have the ability to colonize different habitats, including soil, sediment, water, and both epiphytes and endophytes as host plants, has been suggested for sustainable agriculture. Methylotrophic bacteria are known to play a significant role in the biogeochemical cycle in soil ecosystems, ultimately fortifying plants and sustaining agriculture. Methylotrophs also improve air quality by using volatile organic compounds such as dichloromethane, formaldehyde, methanol, and formic acid. Additionally, methylotrophs are involved in phosphorous, nitrogen, and carbon cycling and can help reduce global warming. In this review, different aspects of the interaction between methylotrophs and host plants are discussed, including the role of methylotrophs in phosphorus acquisition, nitrogen fixation, phytohormone production, iron chelation, and plant growth promotion, and co-inoculation of these bacteria as biofertilizers for viable agriculture practices. PMID:27263015

  12. Resource Guide to Educational Materials about Agriculture. A Project of Agriculture in the Classroom. 1996 Edition.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC. Office of the Secretary.

    This resource guide provides a list of materials available from public and private sources on agriculture and related issues. More than 300 organizations and publishers were asked what materials they were producing that could help regular K-12 classroom teachers incorporate more information about agriculture into their instruction. This guide is…

  13. Pump apparatus including deconsolidator

    SciTech Connect

    Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

    2014-10-07

    A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

  14. Agricultural fuel crops, 201-county Tennessee Valley region

    SciTech Connect

    Madewell, C.E.; D'Souza, G.E.; Esensoy, Y.; Broder, J.D.; Simpson, G.S.

    1983-11-01

    The main objective of the report is to identify and analyze the potential economic and environmental impacts arising from the supplementation of a conventional liquid fuels energy system utilizing fossil-derived fuels with a renewable liquid fuels energy source relying primarily on agricultural fuel crops. The scope of this study is limited to the 201 counties of the Tennessee Valley region. Corn and soybeans, the two predominant crops in this region, are used as surrogates around which certain scenarios are constructed to evaluate the impacts of agricultural fuel crops production. Corn and soybeans are believed to represent greatest regional impact cases. Further, this report presents a data base and inventory summary of the region's agricultural land resources, crops and crop residues, land use patterns, erosion problems, conservation needs, and land suitability and potential availability for fuel crop production. Also included is a profile of institutions associated with agricultural fuel crop production, together with functions and responsibilities. The study is multidisciplinary in nature and is part of the overall biomass integrated environmental assessment for the Tennessee Valley region. The report contains the following sections: (1) inventory summary of Tennessee Valley agricultural resources; crops and crop residues; land use; current erosion status; trends in crop and use and yields; land suitability and potential availability for fuel crops production; and background information on alcohol and major economic related factors; (2) economic and environmental impacts arising from production of corn for ethanol fuel; (3) crop residue availability in the Tennessee Valley; (4) an integrated environmental assessment of vegetable oil crops; and (5) profile of institutions associated with agricultural fuel crops production including policies, functions, and responsibilities. 87 references, 17 figures, 29 tables.

  15. Crop Farm Employee. Agricultural Cooperative Training. Vocational Agriculture. Revised.

    ERIC Educational Resources Information Center

    Boyd, Chester; And Others

    Designed for students enrolled in the Vocational Agricultural Cooperative Part-Time Training Program, this course of study contains 13 units for crop farm employees. Units include (examples of unit topics in parentheses): introduction (opportunities in farming, farming as a science, and farming in the United States), farm records (keeping farm…

  16. Theme: Delivering Agricultural Literacy.

    ERIC Educational Resources Information Center

    Reed, Warren D.; And Others

    1990-01-01

    Eight articles in this theme issue deal with the nationwide implementation of agricultural literacy programs--discovering how to do it. Discussed are experiences in planning and conducting agricultural literacy programs at state and local levels. (JOW)

  17. Traditional Agriculture and Permaculture.

    ERIC Educational Resources Information Center

    Pierce, Dick

    1997-01-01

    Discusses benefits of combining traditional agricultural techniques with the concepts of "permaculture," a framework for revitalizing traditions, culture, and spirituality. Describes school, college, and community projects that have assisted American Indian communities in revitalizing sustainable agricultural practices that incorporate cultural…

  18. Vocational Agriculture in Ponape

    ERIC Educational Resources Information Center

    Dayrit, Ruben S.

    1975-01-01

    The general objectives of agriculture education in both the elementary and secondary schools in Ponape District are to develop interest in agriculture among students and to provide practical and technical skills in growing crops and raising domestic animals. (Author)

  19. Strategies for Agriculture.

    ERIC Educational Resources Information Center

    Crosson, Pierre R.; Rosenberg, Norman J.

    1989-01-01

    Discusses the change of agricultural methods with human population growth. Describes the trends of world food production, changes in farmland, use of fertilizer, and 13 agricultural research institutions. Lists 5 references for further reading. (YP)

  20. Climate Change Effects on Agriculture: Economic Responses to Biophysical Shocks

    NASA Technical Reports Server (NTRS)

    Nelson, Gerald C.; Valin, Hugo; Sands, Ronald D.; Havlik, Petr; Ahammad, Helal; Deryng, Delphine; Elliott, Joshua; Fujimori, Shinichiro; Hasegawa, Tomoko; Heyhoe, Edwina

    2014-01-01

    Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and data. This paper is part of a collective effort to systematically integrate these three types of models. We focus on the economic component of the assessment, investigating how nine global economic models of agriculture represent endogenous responses to seven standardized climate change scenarios produced by two climate and five crop models. These responses include adjustments in yields, area, consumption, and international trade. We apply biophysical shocks derived from the Intergovernmental Panel on Climate Change's representative concentration pathway with end-of-century radiative forcing of 8.5 W/m(sup 2). The mean biophysical yield effect with no incremental CO2 fertilization is a 17% reduction globally by 2050 relative to a scenario with unchanging climate. Endogenous economic responses reduce yield loss to 11%, increase area of major crops by 11%, and reduce consumption by 3%. Agricultural production, cropland area, trade, and prices show the greatest degree of variability in response to climate change, and consumption the lowest. The sources of these differences include model structure and specification; in particular, model assumptions about ease of land use conversion, intensification, and trade. This study identifies where models disagree on the relative responses to climate shocks and highlights research activities needed to improve the representation of agricultural adaptation responses to climate change.

  1. Climate change effects on agriculture: economic responses to biophysical shocks.

    PubMed

    Nelson, Gerald C; Valin, Hugo; Sands, Ronald D; Havlík, Petr; Ahammad, Helal; Deryng, Delphine; Elliott, Joshua; Fujimori, Shinichiro; Hasegawa, Tomoko; Heyhoe, Edwina; Kyle, Page; Von Lampe, Martin; Lotze-Campen, Hermann; Mason d'Croz, Daniel; van Meijl, Hans; van der Mensbrugghe, Dominique; Müller, Christoph; Popp, Alexander; Robertson, Richard; Robinson, Sherman; Schmid, Erwin; Schmitz, Christoph; Tabeau, Andrzej; Willenbockel, Dirk

    2014-03-01

    Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and data. This paper is part of a collective effort to systematically integrate these three types of models. We focus on the economic component of the assessment, investigating how nine global economic models of agriculture represent endogenous responses to seven standardized climate change scenarios produced by two climate and five crop models. These responses include adjustments in yields, area, consumption, and international trade. We apply biophysical shocks derived from the Intergovernmental Panel on Climate Change's representative concentration pathway with end-of-century radiative forcing of 8.5 W/m(2). The mean biophysical yield effect with no incremental CO2 fertilization is a 17% reduction globally by 2050 relative to a scenario with unchanging climate. Endogenous economic responses reduce yield loss to 11%, increase area of major crops by 11%, and reduce consumption by 3%. Agricultural production, cropland area, trade, and prices show the greatest degree of variability in response to climate change, and consumption the lowest. The sources of these differences include model structure and specification; in particular, model assumptions about ease of land use conversion, intensification, and trade. This study identifies where models disagree on the relative responses to climate shocks and highlights research activities needed to improve the representation of agricultural adaptation responses to climate change. PMID:24344285

  2. Climate change effects on agriculture: economic responses to biophysical shocks.

    PubMed

    Nelson, Gerald C; Valin, Hugo; Sands, Ronald D; Havlík, Petr; Ahammad, Helal; Deryng, Delphine; Elliott, Joshua; Fujimori, Shinichiro; Hasegawa, Tomoko; Heyhoe, Edwina; Kyle, Page; Von Lampe, Martin; Lotze-Campen, Hermann; Mason d'Croz, Daniel; van Meijl, Hans; van der Mensbrugghe, Dominique; Müller, Christoph; Popp, Alexander; Robertson, Richard; Robinson, Sherman; Schmid, Erwin; Schmitz, Christoph; Tabeau, Andrzej; Willenbockel, Dirk

    2014-03-01

    Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and data. This paper is part of a collective effort to systematically integrate these three types of models. We focus on the economic component of the assessment, investigating how nine global economic models of agriculture represent endogenous responses to seven standardized climate change scenarios produced by two climate and five crop models. These responses include adjustments in yields, area, consumption, and international trade. We apply biophysical shocks derived from the Intergovernmental Panel on Climate Change's representative concentration pathway with end-of-century radiative forcing of 8.5 W/m(2). The mean biophysical yield effect with no incremental CO2 fertilization is a 17% reduction globally by 2050 relative to a scenario with unchanging climate. Endogenous economic responses reduce yield loss to 11%, increase area of major crops by 11%, and reduce consumption by 3%. Agricultural production, cropland area, trade, and prices show the greatest degree of variability in response to climate change, and consumption the lowest. The sources of these differences include model structure and specification; in particular, model assumptions about ease of land use conversion, intensification, and trade. This study identifies where models disagree on the relative responses to climate shocks and highlights research activities needed to improve the representation of agricultural adaptation responses to climate change.

  3. Optical modulator including grapene

    DOEpatents

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  4. Biotechnology and Agriculture.

    ERIC Educational Resources Information Center

    Kenney, Martin

    Even at this early date in the application of biotechnology to agriculture, it is clear that agriculture may provide the largest market for new or less expensive biotechnologically manufactured products. The chemical and pharmaceutical industries that hold important positions in agricultural inputs are consolidating their positions by purchasing…

  5. Agriculture Business and Management.

    ERIC Educational Resources Information Center

    Seperich, George; And Others

    This curriculum guide is intended for vocational agriculture teachers who deliver agricultural business and management programs at the secondary or postsecondary level. It is based on the Arizona validated occupational competencies and tasks for management and supervisory positions in agricultural business. The competency/skill and task list…

  6. Agricultural Education: Value Adding.

    ERIC Educational Resources Information Center

    Riesenberg, Lou E.; And Others

    1989-01-01

    This issue develops the theme of "Agricultural Education--Value Adding." The concept value adding has been a staple in the world of agricultural business for describing adding value to a commodity that would profit the producer and the local community. Agricultural education should add value to individuals and society to justify agricultural…

  7. Chapter 3: Cropland Agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2013, cropland agriculture resulted in total emissions of approximately 209 MMT CO2 eq. of greenhouse gases (GHG). Cropland agriculture is responsible for almost half (46%) of all emissions from the agricultural sector. Nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) emissions from c...

  8. Dutch Agricultural Education.

    ERIC Educational Resources Information Center

    Netherlands Ministry of Agriculture and Fisheries, The Hauge.

    Agricultural Education in the Netherlands is categorized as Scientific, Higher Secondary, Middle Secondary, and Lower Secondary. Scientific education is given at the agricultural university which has a 6- or 7-year curriculum. Higher secondary education is given at agricultural and horticultural colleges with a 3- to 4-year curriculum. Middle…

  9. Agricultural Structures, Volume II.

    ERIC Educational Resources Information Center

    Linhardt, Richard E.; Burhoe, Steve

    This guide to a curriculum unit in agricultural structures is designed to expand the curriculum materials available in vocational agriculture in Missouri. It and Agricultural Structures I (see note) provide reference materials to systematize the curriculum. The six units cover working with concrete (19 lessons, 2 laboratory exercises), drawing and…

  10. Beyond conservation agriculture.

    PubMed

    Giller, Ken E; Andersson, Jens A; Corbeels, Marc; Kirkegaard, John; Mortensen, David; Erenstein, Olaf; Vanlauwe, Bernard

    2015-01-01

    Global support for Conservation Agriculture (CA) as a pathway to Sustainable Intensification is strong. CA revolves around three principles: no-till (or minimal soil disturbance), soil cover, and crop rotation. The benefits arising from the ease of crop management, energy/cost/time savings, and soil and water conservation led to widespread adoption of CA, particularly on large farms in the Americas and Australia, where farmers harness the tools of modern science: highly-sophisticated machines, potent agrochemicals, and biotechnology. Over the past 10 years CA has been promoted among smallholder farmers in the (sub-) tropics, often with disappointing results. Growing evidence challenges the claims that CA increases crop yields and builds-up soil carbon although increased stability of crop yields in dry climates is evident. Our analyses suggest pragmatic adoption on larger mechanized farms, and limited uptake of CA by smallholder farmers in developing countries. We propose a rigorous, context-sensitive approach based on Systems Agronomy to analyze and explore sustainable intensification options, including the potential of CA. There is an urgent need to move beyond dogma and prescriptive approaches to provide soil and crop management options for farmers to enable the Sustainable Intensification of agriculture.

  11. Beyond conservation agriculture.

    PubMed

    Giller, Ken E; Andersson, Jens A; Corbeels, Marc; Kirkegaard, John; Mortensen, David; Erenstein, Olaf; Vanlauwe, Bernard

    2015-01-01

    Global support for Conservation Agriculture (CA) as a pathway to Sustainable Intensification is strong. CA revolves around three principles: no-till (or minimal soil disturbance), soil cover, and crop rotation. The benefits arising from the ease of crop management, energy/cost/time savings, and soil and water conservation led to widespread adoption of CA, particularly on large farms in the Americas and Australia, where farmers harness the tools of modern science: highly-sophisticated machines, potent agrochemicals, and biotechnology. Over the past 10 years CA has been promoted among smallholder farmers in the (sub-) tropics, often with disappointing results. Growing evidence challenges the claims that CA increases crop yields and builds-up soil carbon although increased stability of crop yields in dry climates is evident. Our analyses suggest pragmatic adoption on larger mechanized farms, and limited uptake of CA by smallholder farmers in developing countries. We propose a rigorous, context-sensitive approach based on Systems Agronomy to analyze and explore sustainable intensification options, including the potential of CA. There is an urgent need to move beyond dogma and prescriptive approaches to provide soil and crop management options for farmers to enable the Sustainable Intensification of agriculture. PMID:26579139

  12. Beyond conservation agriculture

    PubMed Central

    Giller, Ken E.; Andersson, Jens A.; Corbeels, Marc; Kirkegaard, John; Mortensen, David; Erenstein, Olaf; Vanlauwe, Bernard

    2015-01-01

    Global support for Conservation Agriculture (CA) as a pathway to Sustainable Intensification is strong. CA revolves around three principles: no-till (or minimal soil disturbance), soil cover, and crop rotation. The benefits arising from the ease of crop management, energy/cost/time savings, and soil and water conservation led to widespread adoption of CA, particularly on large farms in the Americas and Australia, where farmers harness the tools of modern science: highly-sophisticated machines, potent agrochemicals, and biotechnology. Over the past 10 years CA has been promoted among smallholder farmers in the (sub-) tropics, often with disappointing results. Growing evidence challenges the claims that CA increases crop yields and builds-up soil carbon although increased stability of crop yields in dry climates is evident. Our analyses suggest pragmatic adoption on larger mechanized farms, and limited uptake of CA by smallholder farmers in developing countries. We propose a rigorous, context-sensitive approach based on Systems Agronomy to analyze and explore sustainable intensification options, including the potential of CA. There is an urgent need to move beyond dogma and prescriptive approaches to provide soil and crop management options for farmers to enable the Sustainable Intensification of agriculture. PMID:26579139

  13. NABIC: A New Access Portal to Search, Visualize, and Share Agricultural Genomics Data

    PubMed Central

    Seol, Young-Joo; Lee, Tae-Ho; Park, Dong-Suk; Kim, Chang-Kug

    2016-01-01

    The National Agricultural Biotechnology Information Center developed an access portal to search, visualize, and share agricultural genomics data with a focus on South Korean information and resources. The portal features an agricultural biotechnology database containing a wide range of omics data from public and proprietary sources. We collected 28.4 TB of data from 162 agricultural organisms, with 10 types of omics data comprising next-generation sequencing sequence read archive, genome, gene, nucleotide, DNA chip, expressed sequence tag, interactome, protein structure, molecular marker, and single-nucleotide polymorphism datasets. Our genomic resources contain information on five animals, seven plants, and one fungus, which is accessed through a genome browser. We also developed a data submission and analysis system as a web service, with easy-to-use functions and cutting-edge algorithms, including those for handling next-generation sequencing data. PMID:26848255

  14. NABIC: A New Access Portal to Search, Visualize, and Share Agricultural Genomics Data.

    PubMed

    Seol, Young-Joo; Lee, Tae-Ho; Park, Dong-Suk; Kim, Chang-Kug

    2016-01-01

    The National Agricultural Biotechnology Information Center developed an access portal to search, visualize, and share agricultural genomics data with a focus on South Korean information and resources. The portal features an agricultural biotechnology database containing a wide range of omics data from public and proprietary sources. We collected 28.4 TB of data from 162 agricultural organisms, with 10 types of omics data comprising next-generation sequencing sequence read archive, genome, gene, nucleotide, DNA chip, expressed sequence tag, interactome, protein structure, molecular marker, and single-nucleotide polymorphism datasets. Our genomic resources contain information on five animals, seven plants, and one fungus, which is accessed through a genome browser. We also developed a data submission and analysis system as a web service, with easy-to-use functions and cutting-edge algorithms, including those for handling next-generation sequencing data. PMID:26848255

  15. Climate Change and Agriculture in Africa: Impact Assessment and Adaptation Strategies

    NASA Astrophysics Data System (ADS)

    Brown, Molly E.; McCusker, Brent

    2008-11-01

    As climate change has emerged as a significant threat, there is much concern about how vulnerable agricultural communities will adapt, particularly as global population continues to rise. Much of the current lack of productivity and economic marginalization of African agriculture arises from global trade regimes that give a competitive advantage to Western farmers, from low use of agricultural inputs, and from a dearth of infrastructure and services for the agriculture sector. For centuries, African farmers have used a wide variety of risk-reducing livelihood strategies, including diversifying income sources, switching crops, and investing in marketing. However, improving their productivity to ``modern'' levels has remained a distant dream, resulting in a continual reduction in investment in the sector over the past five decades.

  16. Agricultural Science Protects Our Environment.

    ERIC Educational Resources Information Center

    1967

    Included are a 49 frame filmstrip and a script for narrating a presentation. The presentation is aimed at the secondary school level with an emphasis on how agricultural scientists investigate problems in farmland erosion, stream pollution, road building erosion problems, air pollution, farm pollution, pesticides, and insect control by biological…

  17. Single Sheet Agricultural Mechanics Plans.

    ERIC Educational Resources Information Center

    Schumacher, Leon, Ed.

    This packet contains 25 single-page plans for agricultural mechanics projects. Each plan consists of a one-page set of drawings of the object to be made with a list of needed materials, a cut list, and step-by-step construction procedures on the back of the page. Plans for the following wood projects are included: bluebird house, lawn seat, dog…

  18. Agriculture & the Environment. Teacher's Guide.

    ERIC Educational Resources Information Center

    McMurry, Linda Maston

    This teacher's guide offers background information that teachers can use to incorporate topics related to agriculture and the environment into the curriculum. Classroom activities to bring these topics alive for students in grades 6-9 are suggested. Chapters include: (1) Pesticides and Integrated Pest Management; (2) Food Safety; (3) Water…

  19. Agriculture Teachers: An Endangered Species?

    ERIC Educational Resources Information Center

    Hemp, Paul E.

    1979-01-01

    Discusses a 1978 survey highlighting some of the factors which may be related to the critical shortage of agriculture teachers in Illinois and the high rate of turnover among these teachers. These factors include the time required on the job, inadequate salaries, and large classes. (JOW)

  20. On the new GPCC gridded reference data sets of observed (daily) monthly land-surface precipitation since (1988) 1901 published in 2014 including an all seasons open source test product

    NASA Astrophysics Data System (ADS)

    Ziese, Markus; Andreas, Becker; Peter, Finger; Anja, Meyer-Christoffer; Kirstin, Schamm; Udo, Schneider

    2014-05-01

    Since 1989 the Global Precipitation Climatology Centre (GPCC) collects world-wide observational in-situ data from rain gauges in order to provide gridded high quality and resolution land surface precipitation analyses as mandated by WMO's World Climate Research Program and the Global Climate Observing System (GCOS). In doing so a thorough quality control (QC) is performed on the original data prior to its entrance into the ever growing GPCC data archive being the world-wide largest with monthly totals for more than 90000 stations. Since 2012 also daily data is processed and the archive already holds daily data for more than 30000 stations with the aim to reach at least the same scope as for monthly data, ultimately. All archived data stems from various sources, e.g. national meteorological and hydrological services and regional or global data collections and is thus stored in source specific slots, allowing cross-checks on redundant records and subsequent QC at different sophistication levels depending on the timeliness demand on each product. All data products are referenced by digital object identifiers (DOIs all starting with "10.5676/DWD_GPCC/") and thus published in public domain (ftp://ftp-anon.dwd.de/pub/data/gpcc/html/download_gate.html) for minimum 10 years per product and version. In 2014 the monthly Full Data Reanalysis and the Climatology product releases of December 2011 are due for update. As the new Climatology product is also used as background climatology for all other data products, the Monitoring Product shall be re-processed for all years since 1986. Moreover the First Guess Products (daily and monthly) will benefit from the improved climatology. Finally, GPCC will release its first Full Data Daily Reanalysis product comprising the land-surface precipitation for every day since 1 January 1988. It will be extended backward in course of GPCC's participation in the ERA_CLIM2 re-analysis project. The double to triple size of the GPCC data archive

  1. Agricultural work safety efforts by Wisconsin extension agricultural agents.

    PubMed

    Chapman, L J; Schuler, R T; Skjolaas, C A; Wilkinson, T L

    1995-01-01

    This study investigated the agricultural work-related safety and health programming of county-level cooperative extension agents who work through land grant universities to provide a range of educational programs to agricultural producers. A questionnaire was designed and administered to all 89 Wisconsin agriculture and agribusiness extension county faculty. The questionnaire obtained valid responses from 98.9 percent of the agents. Ninety percent of all agents conducted some occupational safety and health promotion programming in the last year. These activities occupied an average of 4.8 days per agent per year. Most of the reported activities were group programs for the agricultural labor force that involved other extension agents and included the use of videotapes. The greatest barrier to more programming was lack of time on the part of both the agricultural work force and the agents. Most extension agents placed greater emphasis on training in how to work safely around hazards than on how to recognize and permanently correct hazards. For future programs agents requested more short format materials to use in programming, such as fact sheets, videotapes, and farm hazard inspection checklists. Agents are important training delivery resources for controlling farm-related injury and disease. Agents could be more effective with more time, better materials, and with more emphasis on hazard correction in workplace safety programs.

  2. Soil Erosion and Agricultural Sustainability

    NASA Astrophysics Data System (ADS)

    Montgomery, D. R.

    2009-04-01

    Data drawn from a global compilation of studies support the long articulated contention that erosion rates from conventionally plowed agricultural fields greatly exceed rates of soil production, erosion under native vegetation, and long-term geological erosion. Whereas data compiled from around the world show that soil erosion under conventional agriculture exceeds both rates of soil production and geological erosion rates by up to several orders of magnitude, similar global distributions of soil production and geological erosion rates suggest an approximate balance. Net soil erosion rates in conventionally plowed fields on the order of 1 mm/yr can erode typical hillslope soil profiles over centuries to millennia, time-scales comparable to the longevity of major civilizations. Well-documented episodes of soil loss associated with agricultural activities date back to the introduction of erosive agricultural methods in regions around the world, and stratigraphic records of accelerated anthropogenic soil erosion have been recovered from lake, fluvial, and colluvial stratigraphy, as well as truncation of soil stratigraphy (such as truncated A horizons). A broad convergence in the results from studies based on various approaches employed to study ancient soil loss and rates of downstream sedimentation implies that widespread soil loss has accompanied human agricultural intensification in examples drawn from around the world. While a broad range of factors, including climate variability and society-specific social and economic contexts — such as wars or colonial relationships — all naturally influence the longevity of human societies, the ongoing loss of topsoil inferred from studies of soil erosion rates in conventional agricultural systems has obvious long-term implications for agricultural sustainability. Consequently, modern agriculture — and therefore global society — faces a fundamental question over the upcoming centuries. Can an agricultural system

  3. Measures of the Effects of Agricultural Practices on Ecosystem Services

    SciTech Connect

    Dale, Virginia H; Polasky, Stephen

    2007-01-01

    Agriculture produces more than just crops. Agricultural practices have environmental impacts that affect a wide range of ecosystem services, including water quality, pollination, nutrient cycling, soil retention, carbon sequestration, and biodiversity conservation. In turn, ecosystem services affect agricultural productivity. Understanding the contribution of various agricultural practices to the range of ecosystem services would help inform choices about the most beneficial agricultural practices. To accomplish this, however, we must overcome a big challenge in measuring the impact of alternative agricultural practices on ecosystem services and of ecosystem services on agricultural production.

  4. Irradiation of northwest agricultural products

    NASA Astrophysics Data System (ADS)

    Eakin, D. E.; Tingey, G. I.

    1985-02-01

    Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect ocntrol procedures are developed and followed. Due to the recognized potential benefits of irradiation, this program was conducted to evaluate the benefits of using irradiation on Northwest agricultural products. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

  5. Agricultural Education. Proceedings of the Central Region Annual Research Conference (44th, Chicago, Illinois, February 24-25, 1990).

    ERIC Educational Resources Information Center

    Kansas State Univ., Manhattan.

    The following papers are included: "Focusing Agricultural Education Research" (Williams); "A Time Series Analysis of Agricultural Education Student Teachers' Perceptions of Agricultural Mechanics Laboratory Management Competencies" (Schumacher, Johnson); "Determination of the Agricultural Mechanics Laboratory Management Inservice Needs of Missouri…

  6. Listening to Include

    ERIC Educational Resources Information Center

    Veck, Wayne

    2009-01-01

    This paper attempts to make important connections between listening and inclusive education and the refusal to listen and exclusion. Two lines of argument are advanced. First, if educators and learners are to include each other within their educational institutions as unique individuals, then they will need to listen attentively to each other.…

  7. Opportunities for Demand Response in California Agricultural Irrigation: A Scoping Study

    SciTech Connect

    Marks, Gary; Wilcox, Edmund; Olsen, Daniel; Goli, Sasank

    2013-01-02

    California agricultural irrigation consumes more than ten billion kilowatt hours of electricity annually and has significant potential for contributing to a reduction of stress on the grid through demand response, permanent load shifting, and energy efficiency measures. To understand this potential, a scoping study was initiated for the purpose of determining the associated opportunities, potential, and adoption challenges in California agricultural irrigation. The primary research for this study was conducted in two ways. First, data was gathered and parsed from published sources that shed light on where the best opportunities for load shifting and demand response lie within the agricultural irrigation sector. Secondly, a small limited survey was conducted as informal face-to-face interviews with several different California growers to get an idea of their ability and willingness to participate in permanent load shifting and/or demand response programs. Analysis of the data obtained from published sources and the survey reveal demand response and permanent load shifting opportunities by growing region, irrigation source, irrigation method, grower size, and utility coverage. The study examines some solutions for demand response and permanent load shifting in agricultural irrigation, which include adequate irrigation system capacity, automatic controls, variable frequency drives, and the contribution from energy efficiency measures. The study further examines the potential and challenges for grower acceptance of demand response and permanent load shifting in California agricultural irrigation. As part of the examination, the study considers to what extent permanent load shifting, which is already somewhat accepted within the agricultural sector, mitigates the need or benefit of demand response for agricultural irrigation. Recommendations for further study include studies on how to gain grower acceptance of demand response as well as other related studies such as

  8. Lunar outpost agriculture

    NASA Technical Reports Server (NTRS)

    Hossner, Lloyd R.; Ming, Douglas W.; Henninger, Donald L.; Allen, Earl R.

    1991-01-01

    The development of a CELSS for a lunar outpost is discussed. It is estimated that a lunar outpost life support system with a crew of four that produces food would break even in terms of mass and cost to deliver the system to the lunar surface after 2.5 years when compared to the cost of resupply from earth. A brief review is made of research on life support systems and NASA projects for evaluating CELSS components. The use of on-site materials for propellants, construction materials, and agriculture is evaluated, and the use of microbes for waste decomposition and stabilization of ecological balance is touched upon. Areas for further investigation include the behavior of organisms in microgravity, genetic alteration, gas exchange capabilities of organisms, integration of biological and physicochemical components, and automation. The development stages leading to lunar deployment are outlined.

  9. Agricultural Products: Program Planning Guide: Volume 4.

    ERIC Educational Resources Information Center

    Welton, Richard; Robb, Sam

    The program planning guide for agricultural products was written to assist Applied Biological and Agricultural Occupations (ABAO) teachers in enriching existing programs and/or to provide the basis for expansion of offerings to include additional materials for the cluster areas of meat and meat byproducts, dairy processing, fruit and vegetable…

  10. Measurement of gas and aerosol agricultural emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies of air quality indicate that agricultural emissions may impact particulate mass concentrations through both primary and secondary processes. Agriculture impacts can include primary dust emission, on-facility combustion from vehicles or seasonal field burning, and gaseous emissions from waste...

  11. An Integrated Approach to Teaching Agriculture.

    ERIC Educational Resources Information Center

    Jenkinson, G. M.; And Others

    1989-01-01

    Outlines developments that took place in teaching agriculture at the freshman-sophomore level and the concept of integrated courses in agriculture. Future directions include: more emphasis on the impact of technology, case-study forms, and efforts to shift the balance from content to concept. (Author/RT)

  12. Agricultural aviation application in the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The United States has the most advanced equipment and applications in agricultural aviation. It also has a complete service system in agricultural aviation. This article introduces the current status of aerial application including service, equipment, and aerial application techniques. It has a c...

  13. Agriculture waste and rising CO2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Currently, there are many uncertainties concerning agriculture’s role in global environmental change including the effects of rising atmospheric CO2 concentration. A viable and stable world food supply depends on productive agricultural systems, but environmental concerns within agriculture have to...

  14. Migrant labor in agriculture: an international comparison.

    PubMed

    Martin, P L

    1985-01-01

    The May 1984 Conference on Migrant Labor in Agriculture at the University of California-Davis discussed papers by 22 farm labor experts from 12 nations. Each industrial nation utilizes a different set of public and private policies to supply workers for labor-intensive agriculture, but none is entirely satisfactory. Labor-intensive agriculture is becoming more dependent on workers who are shut out of labor markets. Some countries have simply accepted foreign workers in agriculture, while others have adopted policies to integrate farm and nonfarm labor markets. Polices to reduce agriculture's reliance on workers-without-options include restructuring employment practices to employ fewer seasonal workers for longer periods, mechanizing production, and importing fruits and vegetables from nearby developing countries. This article explains the salient features of labor-intensive agriculture, the various polices for obtaining seasonal farmworkers, and options to reduce farming's dependence on migrant labor.

  15. Health and safety strategy in Swedish agriculture.

    PubMed

    Lundqvist, Peter; Svennefelt, Catharina Alwall

    2012-01-01

    In Sweden there is a joint focus on injury prevention in agriculture and this is coordinated through the Swedish Committee on Working Environment (LAMK). LAMK is a network working for a good, healthy and safe working environment in Swedish agriculture from the view of the enterprise with the humans in focus. It is a committee consisting of representatives of authorities, institutions, companies, research & education institutions and organisations referring to the green sector. Examples of on-going initiatives & partners are presented which are included in this mission against injuries in agriculture. It involves the Swedish Work Environment Authority,, the Federation of Swedish Farmers (LRF), the Swedish Institute of Agricultural and Environmental Engineering, Swedish University of Agricultural Sciences (SLU, the Federation of Swedish Forestry and Agricultural Employers (SLA) and the Swedish Municipal Worker's Union. PMID:22317540

  16. Agricultural waste utilization and management

    SciTech Connect

    Not Available

    1985-01-01

    These papers were presented at a symposium on the management and use of agricultural waste products, including food industry wastes. Topics covered include fat and protein recovery from fish wastes, treatments for straw to improve its digestibility, using food industry wastes as animal feeds, various manure treatments and studies of its combustion properties, fermentation, methane and ethanol production, hemp waste water treatment, and heat recovery from manure combustion.

  17. SOLERAS: Rural/agricultural project technical overview

    SciTech Connect

    Huraib, F.S.; Adcock, J.P.; Knect, R.D.

    1987-04-01

    The objective of the Rural and Agricultural Solar Applications Projects is to enhance the quality of rural life in hot, arid climates by providing systems that use renewable or regenerable energy sources for domestic or communal, agricultural, and local industrial applications. These systems must provide domestic services such as hot water, heat for cooking, and electric power for lighting, communications, and refrigeration. In addition, agricultural applications such as water desalination, irrigation pumping, and heat and electricity for crop or food processing and local industrial functions, can become the basis for improving the villagers' standard of living. 29 refs., 82 figs., 23 tabs.

  18. Simplified overturn stability monitoring of agricultural tractors.

    PubMed

    Nichol, C I; Sommer, H J; Murphy, D J

    2005-02-01

    Agricultural tractors are the most common source of farm work fatalities in the U.S., with overturns the most common type of incident. For the year 2001, there were 15 tractor-related fatalities in Pennsylvania, 9 of which were due to tractor rollover. A new device using low-cost sensors and microcomputers was developed around a simplified mathematical model of an agricultural tractor to inform the operator of potential tractor instability. This device communicates the current rollover potential, along with a recent history of rollover potential, to the operator of the tractor via a simple bar-graph display. The device uses a single-chip accelerometer to sense the current rollover potential and a small microprocessor to analyze the accelerometer data, compensate for variations due to temperature, and then send this information to a visual display. The use of these low-cost "off the shelf" components enabled the fabrication of a very inexpensive sensor system. Because agricultural tractors have a long service life, it was important to make the device low cost and flexible. This could enable it to be sold as an aftermarket add-on for a variety of tractor models. The device is also capable of interfacing with newer on-board tractor systems via a CAN bus to make it more attractive to tractor manufacturers who may want to incorporate this device into new models. Work is continuing on the development of an improved display to inform the tractor operator of possible instability, including display ergonomic studies, investigation of threshold levels for alerting an operator of potential instability, and investigation into audible warning signals.

  19. 7 CFR 3560.66 - Participation with other funding or financing sources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... in accordance with 7 CFR 1924, subparts A and C. If housing includes non-Agency financed common... 7 Agriculture 15 2010-01-01 2010-01-01 false Participation with other funding or financing sources... Grant Origination § 3560.66 Participation with other funding or financing sources. (a)...

  20. 7 CFR 2.68 - Administrator, National Agricultural Statistics Service.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... avoid disclosure of confidential data or information supplied by any person, firm, partnership... agreements to further research and statistical reporting programs in the food and agricultural sciences (7 U... committees concerned with agricultural science, education, and development activities, including library...

  1. A threshold area ratio of organic to conventional agriculture causes recurrent pathogen outbreaks in organic agriculture.

    PubMed

    Adl, S; Iron, D; Kolokolnikov, T

    2011-05-01

    Conventional agriculture uses herbicides, pesticides, and chemical fertilizers that have the potential to pollute the surrounding land, air and water. Organic agriculture tries to avoid using these and promotes an environmentally friendly approach to agriculture. Instead of relying on herbicides, pesticides and chemical fertilizers, organic agriculture promotes a whole system approach to managing weeds, pests and nutrients, while regulating permitted amendments. In this paper, we consider the effect of increasing the total area of agricultural land under organic practices, against a background of conventional agriculture. We hypothesized that at a regional scale, organic agriculture plots benefit from existing in a background of conventional agriculture, that maintains low levels of pathogens through pesticide applications. We model pathogen dispersal with a diffusive logistic equation in which the growth/death rate is spatially heterogeneous. We find that if the ratio of the organic plots to conventional plots remains below a certain threshold l(c), the pest population is kept small. Above this threshold, the pest population in the organic plots grows rapidly. In this case, the area in organic agriculture will act as a source of pest to the surrounding region, and will always infect organic plots as they become more closely spaced. Repeated localized epidemics of pest outbreaks threaten global food security by reducing crop yields and increasing price volatility. We recommend that regional estimates of this threshold are necessary to manage the growth of organic agriculture region by region.

  2. A threshold area ratio of organic to conventional agriculture causes recurrent pathogen outbreaks in organic agriculture.

    PubMed

    Adl, S; Iron, D; Kolokolnikov, T

    2011-05-01

    Conventional agriculture uses herbicides, pesticides, and chemical fertilizers that have the potential to pollute the surrounding land, air and water. Organic agriculture tries to avoid using these and promotes an environmentally friendly approach to agriculture. Instead of relying on herbicides, pesticides and chemical fertilizers, organic agriculture promotes a whole system approach to managing weeds, pests and nutrients, while regulating permitted amendments. In this paper, we consider the effect of increasing the total area of agricultural land under organic practices, against a background of conventional agriculture. We hypothesized that at a regional scale, organic agriculture plots benefit from existing in a background of conventional agriculture, that maintains low levels of pathogens through pesticide applications. We model pathogen dispersal with a diffusive logistic equation in which the growth/death rate is spatially heterogeneous. We find that if the ratio of the organic plots to conventional plots remains below a certain threshold l(c), the pest population is kept small. Above this threshold, the pest population in the organic plots grows rapidly. In this case, the area in organic agriculture will act as a source of pest to the surrounding region, and will always infect organic plots as they become more closely spaced. Repeated localized epidemics of pest outbreaks threaten global food security by reducing crop yields and increasing price volatility. We recommend that regional estimates of this threshold are necessary to manage the growth of organic agriculture region by region. PMID:21420722

  3. 7 CFR 1755.98 - List of telecommunications specifications included in other 7 CFR parts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false List of telecommunications specifications included in other 7 CFR parts. 1755.98 Section 1755.98 Agriculture Regulations of the Department of Agriculture... included in other 7 CFR parts. The following specifications are included throughout 7 CFR chapter...

  4. A review of groundwater recharge under irrigated agriculture in Australia

    NASA Astrophysics Data System (ADS)

    Riasat, Ali; Mallants, Dirk; Walker, Glen; Silberstein, Richard

    2014-05-01

    Quantification of recharge under irrigated agriculture is one of the most important but difficult tasks. It is the least understood component in groundwater studies because of its large variability in space and time and the difficulty of direct measurement. Better management of groundwater resources is only possible if we can accurately determine all fluxes going into and out of a groundwater system. One of the major challenges facing irrigated agriculture in Australia, and the world, is to reduce uncertainty in estimating or measuring the recharge flux. Reducing uncertainty in groundwater recharge under irrigated agriculture is a pre-requisite for effective, efficient and sustainable groundwater resource management especially in dry areas where groundwater usage is often the key to economic development. An accurate quantification of groundwater recharge under irrigated systems is also crucial because of its potential impacts on soil profile salinity, groundwater levels and groundwater quality. This paper aims to identify the main recharge control parameters thorough a review of past field and modelling recharge studies in Australia. We find that the main recharge control parameters under irrigated agriculture are soil type, irrigation management, watertable depth, land cover or plant water uptake, soil surface conditions, and soil, irrigation water and groundwater chemistry. The most commonly used recharge estimation approaches include chloride mass balance, water budget equation, lysimeters, Darcy's law and numerical models. Main sources and magnitude of uncertainty in recharge estimates associated with these approaches are discussed.

  5. [Towards a renewable and sustainable agriculture. Biological agriculture: from marginal vanguard to spearhead of the agriculture of the future].

    PubMed

    Diek Van Mansvelt, J

    1992-01-01

    This work seeks to demonstrate how different types of organic agriculture can meet the need for renewable and sustainable agriculture, rural development, and management of the land and water resources. An obstacle to the spread of organic agriculture is the widespread perception that without intensive factors of production, demographic growth will necessarily outstrip the available food resources. Calculation of economic costs and benefits at present carries greater weight in planning than do soil erosion, deforestation, extinction of species, disappearance of habitats, and similar environmental damage. The different types of organic agriculture do not follow rigid rules and are not defined solely by the nonuse of nitrogenous fertilizers and pesticides. One of the main principles or organic agriculture is to respect local soil and climatic conditions. Self-sufficiency regarding external factors of production and an emphasis on recycling and optimal use of natural resources were concept ahead of their time when they initially were introduced in the 1920s. The specialization which restructured agriculture over the past century has seriously damaged the system of mixed agriculture and the chain of food production. The solution will be to seek for each region an appropriate balance linking animals and agricultural production in an organic process. The objective of organic agriculture, also known as autonomous ecosystem management, is to preserve as far as possible the balance between needs for food and fiber on the 1 hand and the potential of local ecosystems on the other. General principles of organic agriculture include mixed exploitation in which both plants and animals have specific functions in the context of their local soil and climatic characteristics. Different types of crop rotation are practiced to optimize mutual interactions between crops, and the varied organic cycles are also optimized within the framework of anorganic management in accord with nature

  6. Agricultural Occupations Program Planning Guide.

    ERIC Educational Resources Information Center

    Hemp, Paul E.; Mayer, Leon

    The major program objectives of agricultural occupations courses are (1) to develop agricultural competencies needed by individuals engaged in or preparing to engage in production agriculture, and in agricultural occupations other than production agriculture; (2) to develop an understanding of the career opportunities in agriculture; (3) to…

  7. Groundwater recharge and agricultural contamination

    NASA Astrophysics Data System (ADS)

    Böhlke, John-Karl

    2002-02-01

    Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water-rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agricultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3 -, N2, Cl, SO4 2-, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well as a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3 -, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.

  8. Agriculture and water quality. Agriculture Information Bulletin

    SciTech Connect

    Crowder, B.M.; Ribaudo, M.O.; Young, C.E.

    1988-08-01

    Agriculture generates byproducts that may contribute to the contamination of the Nation's water supply. Any effective regulations to ban or restrict agricultural-chemical or land-use practices in order to improve water quality will affect the farm economy. Some farmers will benefit; some will not. Most agricultural pollutants reach surface waterways in runoff; some leach through soil into ground water. Because surface-water systems and ground water systems are interrelated, farm-management practices need to focus on water quality in both systems. Modifying farm-management practices may raise production costs in some areas. Farmers can reduce runoff losses by reducing input use, implementing soil-conservation practices, and changing land use. Also at issue is who should pay for improving water quality.

  9. Sustainable Agriculture as a Recruitment Tool for Geoscience Majors

    NASA Astrophysics Data System (ADS)

    Enright, K. P.; Gilbert, L. A.; McGillis, A.

    2014-12-01

    Small-scale agriculture has exploded with popularity in recent years, as teenagers and college students gain interest in local food sources. Outdoor experiences, including gardening and farming, are often among the motivations for students to take their first geoscience courses in college. The methods and theories of small agriculture translate well into geologic research questions, especially in the unique setting of college campus farms and gardens. We propose an activity or assignment to engage student-farmers in thinking about geosciences, and connect them with geoscience departments as a gateway to the major and career field. Furthermore, the activity will encourage a new generation of passionate young farmers to integrate the principles of earth science into their design and implementation of more sustainable food systems. The activity includes mapping, soil sampling, and interviewing professionals in agriculture and geology, and results in the students writing a series of recommendations for their campus or other farm. The activity includes assessment tools for instructors and can be used to give credit for a summer farming internship or as part of a regular course. We believe reaching out to students interested in farming could be an important recruitment tool for geosciences and helps build interdisciplinary and community partnerships.

  10. Agricultural aviation research

    NASA Technical Reports Server (NTRS)

    Chevalier, H. L. (Compiler); Bouse, L. F. (Compiler)

    1977-01-01

    A compilation of papers, comments, and results is provided during a workshop session. The purpose of the workshop was to review and evaluate the current state of the art of agricultural aviation, to identify and rank potentially productive short and long range research and development areas, and to strengthen communications between research scientists and engineers involved in agricultural research. Approximately 71 individuals actively engaged in agricultural aviation research were invited to participate in the workshop. These were persons familiar with problems related to agricultural aviation and processing expertise which are of value for identifying and proposing beneficial research.

  11. Effects of low-grade weirs on soil microbial communities to advance agricultural best management practices for nitrate remediation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural activities throughout the Mississippi River Basin have been identified as a major source of nutrient pollution, particularly nitrogen from fertilizer application, to downstream waters including the Gulf of Mexico. Utilizing best management practices, such as low-grade weirs have been id...

  12. Managing agricultural phosphorus for water quality: lessons from the USA and China.

    PubMed

    Sharpley, Andrew; Wang, Xiaoyan

    2014-09-01

    The accelerated eutrophication of freshwaters and to a lesser extent some coastal waters is primarily driven by phosphorus (P) inputs. While efforts to identify and limit point source inputs of P to surface waters have seen some success, nonpoint sources remain difficult to identify, target, and remediate. As further improvements in wastewater treatment technologies becomes increasingly costly, attention has focused more on nonpoint source reduction, particularly the role of agriculture. This attention was heightened over the last 10 to 20 years by a number of highly visible cases of nutrient-related water quality degradation; including the Lake Taihu, Baltic Sea, Chesapeake Bay, and Gulf of Mexico. Thus, there has been a shift to targeted management of critical sources of P loss. In both the U.S. and China, there has been an intensification of agricultural production systems in certain areas concentrate large amounts of nutrients in excess of local crop and forage needs, which has increased the potential for P loss from these areas. To address this, innovative technologies are emerging that recycle water P back to land as fertilizer. For example, in the watershed of Lake Taihu, China one of the largest surface fresh waters for drinking water supply in China, local governments have encouraged innovation and various technical trials to harvest harmful algal blooms and use them for bio-gas, agricultural fertilizers, and biofuel production. In any country, however, the economics of remediation will remain a key limitation to substantial changes in agricultural production. PMID:25193824

  13. Managing agricultural phosphorus for water quality: lessons from the USA and China.

    PubMed

    Sharpley, Andrew; Wang, Xiaoyan

    2014-09-01

    The accelerated eutrophication of freshwaters and to a lesser extent some coastal waters is primarily driven by phosphorus (P) inputs. While efforts to identify and limit point source inputs of P to surface waters have seen some success, nonpoint sources remain difficult to identify, target, and remediate. As further improvements in wastewater treatment technologies becomes increasingly costly, attention has focused more on nonpoint source reduction, particularly the role of agriculture. This attention was heightened over the last 10 to 20 years by a number of highly visible cases of nutrient-related water quality degradation; including the Lake Taihu, Baltic Sea, Chesapeake Bay, and Gulf of Mexico. Thus, there has been a shift to targeted management of critical sources of P loss. In both the U.S. and China, there has been an intensification of agricultural production systems in certain areas concentrate large amounts of nutrients in excess of local crop and forage needs, which has increased the potential for P loss from these areas. To address this, innovative technologies are emerging that recycle water P back to land as fertilizer. For example, in the watershed of Lake Taihu, China one of the largest surface fresh waters for drinking water supply in China, local governments have encouraged innovation and various technical trials to harvest harmful algal blooms and use them for bio-gas, agricultural fertilizers, and biofuel production. In any country, however, the economics of remediation will remain a key limitation to substantial changes in agricultural production.

  14. Amount, composition and seasonality of dissolved organic carbon and nitrogen export from agriculture in contrasting climates

    NASA Astrophysics Data System (ADS)

    Graeber, Daniel; Meerhof, Mariana; Zwirnmann, Elke; Ovesen, Niels; Gelbrecht, Jörg; Teixeira de Mello, Franco; González-Bergonzoni, Ivan; Jeppesen, Erik; Kronvang, Brian

    2014-05-01

    ratios. The high seasonality of DOM, especially in the Uruguayan streams implies high influence of variation of the environmental conditions, both temperature and precipitation. Our study shows the importance of agriculture as DOM source in both climate zones, with a high seasonality particularly in Uruguayan streams. Future investigations and models of DOC and DON export in agricultural catchments need to include this seasonality to give correct information on the catchment export. Moreover, our results clearly show that DON is increasingly important for the nitrogen export from agricultural catchments when moving from a temperate to a warmer climate.

  15. Sustainable Agriculture Course Delivered Nationally via Satellite.

    ERIC Educational Resources Information Center

    Salvador, R. J.; And Others

    1993-01-01

    Describes an instructional model for a sustainable agriculture telecourse offered nationally by Iowa State University. Includes preproduction activities; technology employed; budget; time requirements; course content; student postevaluation results. Provides information and suggestions for individuals and institutions considering production or…

  16. Theme: The Latest Trends in Agricultural Education.

    ERIC Educational Resources Information Center

    Agricultural Education Magazine, 2002

    2002-01-01

    Theme issue includes 10 articles on the following topics: innovation, trends in agricultural curriculum, working with special populations, the role of history, standards, curriculum integration, distance learning, integrating math and science, and developing leaders. (JOW)

  17. Effects of conservation practices on fishes, amphibians, and reptiles within agricultural streams and wetlands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation practices have been traditionally used to manage soil and water resources to improve agricultural production, and now include methods to reduce the environmental impacts of agriculture on streams and wetlands. These practices have been regularly implemented within agricultural watershed...

  18. Hands-On Activities and Challenge Tests in Agricultural and Environmental Education

    ERIC Educational Resources Information Center

    Poudel, D. D.; Vincent, L. M.; Anzalone, C.; Huner, J.; Wollard, D.; Clement, T.; DeRamus, A.; Blakewood, G.

    2005-01-01

    Many agricultural and environmental problems are interrelated and overlapping. Several agencies, including nonprofit organizations, have developed programs to educate schoolchildren about agricultural and environmental issues; however, programs that integrate both agricultural and environmental learning, especially among middle and high school…

  19. 7 CFR 319.8-20 - Importations by the Department of Agriculture.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-20 Section 319.8-20 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND... Programs, which conditions may include clearance through the New Crops Research Branch of the Plant Science Research Division, Agricultural Research Services....

  20. Nonpoint Source Pollution.

    PubMed

    Ahmad, Zaki Uddin; Sakib, Salman; Gang, Daniel Dianchen

    2016-10-01

    Research advances on non-point source pollution in the year 2015 have been depicted in this review paper. Nonpoint source pollution is mainly caused by agricultural runoff, urban stormwater, and atmospheric deposition. Modeling techniques of NPS with different tools are reviewed in this article.