Dissertations / Theses: 'Agricultural best practices'

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Dorner, Sarah M. "Evaluating best management practices for agricultural watersheds using probabilistic models." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0020/MQ55669.pdf.

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Parker, Geoff. "Modeling agricultural best management practices in the South Nation watershed." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/26740.

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The South Nation watershed consists of an area of roughly 3900 km2 in Eastern Ontario which drains into the South Nation River. The South Nation River in turn drains into the Ottawa River at the watershed outlet. The work presented here included the use of the continuous-simulation Annualized Agricultural Non Point Source (AnnAGNPS) 5.0 dynamic pollutant loading model, which was developed by the U.S. Department of Agriculture (USDA). In-stream water chemistry was also an important element of a meaningful analysis. The dynamic water-quality model CE-QUAL-RIV1 was selected due to its riverine nature, which is closely linked with the AnnAGNPS concept of a channel network. Utilities were developed to enhance the input and output capabilities of both codes. The linked models were then calibrated to the available data, and a case matrix focused on predicting feasibility of best management practices (BMPs) within the context of climate change was constructed and simulated. The calibration process was done manually at first, based on the results of a sensitivity analysis conducted on the AnnAGNPS package as part of the work. Subsequently, the use of an automatic genetic-algorithm based approach (also developed as part of this work) was explored, which yielded an improvement in the calibrated model and was therefore used as a base case of the model. The case matrix examined 4 individual BMPs, along with 4 combined BMP scenarios. (Abstract shortened by UMI.)

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Miller, Jennifer Christine. "Farmer Adoption of Best Management Practices Using Incentivized Conservation Programs." ScholarWorks @ UVM, 2014. http://scholarworks.uvm.edu/graddis/275.

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Many farms in the United States impose negative externalities on society. Population growth and the accompanying increase in demand for food further promote this trend of environmental degradation as a by-product of food production. The USDA's Environmental Quality Incentives Program (EQIP) provides financial assistance to farmers who wish to address natural resource concerns by making structural improvements or implementing best management practices (BMPs) on their farms. Regional examinations of program implementation and incentive levels are needed to evaluate the effectiveness of EQIP at both the farm and environmental level. This research addresses this need in the following two ways. First, conjoint analysis was used to calculate the willingness to accept incentive levels desired by Vermont farmers for implementing three common BMPs and the relative importance of each attribute in their adoption decisions. Next, a survey was conducted to document Vermont farmers' experiences, or choices not to engage, with EQIP. The results of the conjoint analysis indicated that farmers' adoption decisions are most heavily influenced by the available implementation incentives and that the higher the incentive level offered, the more willing farmers are to adopt a practice. The survey results triangulated these findings as cost was the most frequently cited challenge farmers face when implementing BMPs and one third of respondents felt the cost-share amount they had received was inadequate. Although 46% of respondents reported receiving nonmonetary benefits, 43% had encountered challenges when enrolling or participating in EQIP. In addition, though contracts are designed to address specific resource concerns, 30% of respondents had not fully fixed the original issues with their contracts. This also indicates that the incentive levels offered in EQIP contracts may be lower than Vermont farmers' preferred incentive levels, affecting the adoption rate of BMPs and subsequently the environmental health and long term sustainability of Vermont's agricultural systems. Program areas ripe for improvement, key points for farmers weighing the costs and benefits of program participation, and future research opportunities are discussed in order to guide efforts to improve the effectiveness of EQIP in Vermont. This research also raises awareness of how much it costs to simultaneously support environmental health and food production in our current food system and who ultimately should bear this financial burden.

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Stavros, Robert William. "The development of an evaluation method for best management practices on agricultural lands." Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/74773.

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To help local, rural planners make decisions on which Best Management Practices (BMPs) are most appropriate for the control of Non-Point Sources of Pollution (NPSP) within their jurisdiction, a method is developed for unbiased site-specific evaluation of BMPs appropriateness. An appropriate BMP is functional, practical and cost effective. The method developed is a rational method suitable for the general evaluation of agricultural BMPs to control NPSP in rural watersheds. The method is functional, practical, and cost effective because it uses existing data and personnel wherever and whenever possible. Unlike other NPSP modeling methods, this method lends itself to the selective application of BMPs throughout the watershed based on its actual land use and physical composition. This means, BMP's can be applied to the entire watershed uniformly or applied to a subset of the watershed based on selection criteria such as field slope, soil type, or existing cover crop. In addition, a combination of selection criteria can be used, and a combination of BMPs. This flexibility in selecting various BMPs and BMP combinations, allows planners to pose many different schemes for controlling NPSP within the watershed. The results of the schemes can be compared to determine which scheme is the most appropriate for use within the specific watershed. The method developed relies heavily on the United States Department of Agriculture's Soil Conservation Service's (SCS) Universal Soil Loss Equation (USLE) and uses data already being collected by the SCS and the Agricultural Stabilization and Conservation Service (ASCS). The method does require the creation of Hydrologic Response Units (HRUs) comprised of unique combinations or soil type and land use areas. To demonstrate the method's ability to select an effective BMPs for a watershed, a series of BMP scenarios were evaluated. The BMP scenarios were divided into three categories: a uniform application of a BMP throughout the watershed; a selective application of a BMP throughout the watershed and; the selective application of a set of BMP's throughout the watershed. Using a series of trial runs, the benefits of using the method were demonstrated. For example, similar results were obtained using a cropping BMP of "Corn, grain, soybean and cover" throughout the sample, and a ''no-till" BMP on 3 percent of the sample. This type of information was used by economic modelers to help target precious BMP implementation dollars. As an indirect result of the method's HRU development, it was possible to test the independence of each of the USLE factors within the Nansemond/Chuckatuck watershed. The results of the Duncan's Multiple Range Test shows an interdependence between the "soil type and the cover", "overland flow versus cover", and "overland flow versus soil type".
Ph. D.

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Daggupati, Naga Prasad. "GIS methods to implement sediment best management practices and locate ephemeral gullies." Diss., Kansas State University, 2012. http://hdl.handle.net/2097/13522.

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Doctor of Philosophy
Department of Biological & Agricultural Engineering
Kyle Douglas-Mankin
Soil erosion is one of the most important of today’s global environmental problems. Over the past few decades, soil conservation practices were implemented to reduce soil erosion in the United States. However, excessive sediment still remains among the most prevalent water quality problems. Agricultural fields and in particular ephemeral gullies (EGs) are considered to be a major contributor of sediment. The overall goal of this study was to improve modeling utility to identify and quantify sources of sediment. Specific objectives were: (1) to develop and demonstrate a method of field-scale targeting using Soil and Water Assessment Tool (SWAT) and to use this method as a targeted, flexible approach to pay explicitly for sediment-yield reductions; (2) to evaluate topographic index models (Slope Area [SA], Compound Topographic Index [CTI], Slope Area Power [SAP] and Wetness Topographic Index [WTI]) and a physical-based model (Overland Flow Turbulent [OFT]) in predicting spatial EG location and lengths. Black Kettle Creek watershed was the focus of an innovative project to pay for modeled field sediment reductions. An Arc-Geographical Information System (GIS) tool bar was developed that post processed SWAT hydrologic response unit output to field boundaries and prepared maps of high-priority fields by sediment, total nitrogen, and total phosphorus and was demonstrated to be useful for field-scale targeting. Calibrated SWAT model was used to establish baseline sediment yields. Various Best Management Practices (BMPs) were simulated and payments to implement each BMP for a given field were calculated. This study helped to guide determination of appropriate farmer support payments and quantified the important influence of BMP type and site-specific conditions for use in targeting conservation practice funding to achieve maximum soil-loss reductions per dollar spent. Extreme care should be used in selecting the source of spatial model input data when using SWAT for field-level targeting. Automated geospatial models were developed in a GIS environment to spatially locate and derive length of EGs using topographic index and physical based models. EG predictions were better for the SA model among the four topographic index models tested. Individual calibration of topographic index model threshold for each application site was needed. An OFT model (physical based model), which utilized topography, precipitation, soil, landuse/landcover and SWAT-based runoff estimates, did not need individual site calibration, and may have broader applicability than empirical based models.

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Cagle, Michael Scott. "Identifying adopters of best management practices within Mississippi beef producers and the reasons for non-adoption." Thesis, Mississippi State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3618196.

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The goal of the Mississippi State University Extension Service (MSU-ES) is to improve the quality of life for all Mississippians. One specific group that agricultural change agents work with at the county level is beef producers. Grazing lands have received much attention over the last few years regarding environmental concerns and Best Management Practices (BMPs) for beef cattle operations.

The adoption of these practices was voluntary during the time this study was conducted, however; adoption was highly encouraged by the MSU-ES and the Natural Resources Conservation Service (NRCS). By knowing the level of adoption of BMPs that Mississippi beef producers have implemented, change agents can more effectively plan educational programming efforts for producers to better understand the importance of BMP adoption.

The purpose of this study was to describe the adopter categories of Mississippi beef producers as determined by Rogers (2003) adopter characteristics generalizations based on their (1) socioeconomic status, (2) personality values and communication behavior, and (3) opinions. It also examined the correlations between the adopter categories to predict the level of the three BMPs being studied.

The adopter categories were innovator, early adopter, early majority, late majority, and laggard. The three BMPs that were the focus of the study were rotation grazing, riparian buffers, and pasture renovation.

The results of the study indicated that Mississippi beef producers could be correctly identified in the adopter categories. By identifying the adopter categories of the Mississippi beef producers and then examining the correlations among the variables, prediction of BMP adoption of rotational grazing and riparian buffers was possible.

The relationships between MSU-ES agents and their programming efforts, as well as the relationships between NRCS district conservationist and their programs, were studied. Non-adoption, though not an adopter category, was also examined and the reasons for it were cited.

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Campbell, Joseph T. "Impacts of Collaborative Watershed Management Policies on the Adoption of Agricultural Best Management Practices." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1212012674.

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Weekes, Christopher Etienne. "Agricultural and Domestic Waste Contamination in Chilibre Panama and Potential Low-Cost Best Managament Practices." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4789.

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Abstract Sanitation coverage in the Republic of Panama is 5 to 10 percent below the Millennium Development Goals targets set for the country. Population growth, urbanization, unplanned development and waste mismanagement have resulted in improvised trash sites and waste discharges into river systems that are important components of the biologically diverse natural environment of Panama. The study sought to investigate and estimate the burden of waste from domestic and agricultural sources in three regions of the Chilibre corrigimiento (district). It was hypothesized that the water quality and land cover data would reflect that the most populated region in the study sample (Region 2) would have more water quality violations than the adjacent background and attenuation regions (Region 1 and Region 3) in the study sample. The results supported that Region 2 had the most water quality violations -- particularly at the CHIL 3 monitoring station. Based on the results the most appropriate best management practices (BMPs) were recommended for the household, community, watershed, and regional level waste management in the study region. Future research will look determine the effectiveness of microfinance programs in bolstering sanitation-based entrepreneurship in Chilibre and across Panama.

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Sisung, Theresa. "Soil testing and nutrient application practices of agricultural retailers in the Great Lakes Region." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32556.

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Master of Agribusiness
Agricultural Economics
Terry Griffin
Agricultural runoff containing phosphorus is believed to be a major contributor of algae blooms in the Western Lake Erie Basin. However, the implementation of best management practices (BMPs) can be used to help reduce the runoff of phosphorus. This research involved conducting surveys to analyze the current implementation of BMPs in Michigan and Indiana. The hypothesis is that the survey results are similar between the two states. An additional hypothesis is that the Michigan and Indiana results are similar to results from two other studies that were previously conducted. The results from this research generally support the hypothesis that a similar number of farmers in Michigan and Indiana are already implementing best management practices on their farms. In addition to the results being similar across Michigan and Indiana, there is also some evidence that shows that the results are similar to studies from the Ohio State University (LaBarge and Prochaska 2014), CropLife magazine (Erickson and Widmar 2015) and NRCS (U.S. Department of Agriculture, Natural Resources Conservation Service 2016); however upon further investigation there are distinct differences before and after media mentions of ramifications from the Lake Erie algal blooms. While it is difficult to force farmers to implement BMPs, the results of this study may help to educate them, which may cause them to add these practices to their operations.

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Duke, Kate Repair. "FCV TOTAL : an analysis of leadership development best practices and recommendations." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/681.

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Cunningham, Janelle Hope. "An Assessment of the Quality of Agricultural Best Management Practices in the James River Basin of Virginia." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/34903.

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Assessment tools were developed to address the need for a low cost, rapid method of quantifying the quality of agricultural best management practices (BMPs). Best management practices are either cost-shared, where some or all of the capital costs of the practice were subsidized with federal, state, or local funds, or non cost-shared, where the cost of the practice and its upkeep is paid for by the landowner or farm operator. Cost-share practices are required to comply with state standards, while non cost-share practices are not subject to any standards. For this study, BMP quality is defined as the adherence to design, site selection, implementation, and maintenance criteria relating to water quality as specified by state and federal agencies promoting BMP implementation. The two objectives of this research were: 1. develop a set of assessment tools to quantify the quality of agricultural best management practices in a rapid low-cost manner, and 2. test the tools and determine if differences in quality exist between cost-share and non cost-share BMPs in the James River Basin of Virginia. Assessment tools were developed for sixteen practices: alternative water systems, stream fencing, streambank stabilization, grass filter strips, wooded buffers, permanent vegetative cover on critically eroding areas, permanent vegetative cover on erodible cropland, reforestation of erodible crop and pasture land, animal waste storage facilities, grazing land protection systems, loafing lot management systems, late winter split application of nitrogen on small grains, protective cover for specialty crops, sidedress application of nitrogen on corn, small grain cover crops-fertilized and harvested, and small grain cover crops for nutrient management. Assessment tools were developed using both Virginia BMP standards and expert knowledge. Virginia Department of Recreation and Conservation (DCR) and Virginia and national Natural Resource Conservation Service (NRCS) BMP standards were collected and sorted into the four quality component categories; design, site selection, implementation, and maintenance. Standards that pertained directly to a BMPs' potential to protect water quality were translated into question format. Multiple-choice or yes/no questions were used as often as possible to avoid potential bias and for ease of processing. Assessment tool development involved an iterative process that included input from a research team (university-based researchers) and an expert team (public and private sector professionals and practitioners responsible for BMP design and assessment). One hundred and fifty-five cost-shared BMPs and 150 non cost-shared BMPs were assessed on 128 independent farms in the James River Basin of Virginia over a period of four months. The assessment tools were loaded onto a personal digital assistant (PDA), which facilitated data collection and eliminated the need for data transcription. Data collected on the PDA were uploaded periodically to a computer database. A digital camera was used to develop a photographic record of the assessed BMPs. Best management practice quality scores were based on five-point scale, with one being the lowest quality score and five as the highest. Statistical analyses conducted on both the overall quality scores and the quality component scores, indicate that there is not a strong significant difference (p = 0.05) in quality between the cost-shared and non cost-shared BMPs assessed for this study. Statistically significant differences between cost-share and non cost-share practices did, however, exist. For the filter/buffer strips practices (grass filter strips and wooded buffers), the implementation quality component cost-share mean (3.35) and the non cost-share mean (3.88) were statistically different at the 0.05 level (p-value = 0.026). One other statistically significant difference was found. For stream fencing, the overall quality cost-share mean was 4.68 while the non cost-share mean was 4.20; the means are statistically different at the 0.05 level (p-value = 0.043). Statistical analyses were performed to determine if age of practice, farm size, or Soil and Water Conservation District (SWCD) had effects on the BMP quality. No statistically significant differences (p = 0.05) were found relating to the age of an assessed BMP or farm size. One SWCD, the Robert E. Lee district, had a statistically significant difference in the design quality component means; cost-share mean = 4.21, non cost-share mean = 2.94 with a p-value of 0.048. The statistically significant differences that were detected do not establish a clear trend; it appears that for the BMPs assessed here the qualities of cost-share and non cost-share practices are roughly equal. The fact that cost-share practices and non cost-share practices do appear to be roughly equal may be the result of education and outreach programs sponsored by Virginia's SWCDs and Virginia Cooperative Extension. Non cost-share practices may be of equal quality to cost-share practices because those implementing BMPs without the benefit of cost-share may have a greater stake (both financial and personal) in those practices performing well. If no statistically significant difference in quality exists between cost-share and non cost-share practices, then non cost-share practices should be treated equally when accounting for BMPs in NPS pollution in watershed management and computer modeling. Currently, only cost-share practices are included in computer models, in part because these are the only practices tracked by the existing BMP establishment infrastructure. Estimating the numbers and distribution of non cost-share practices and incorporating them into NPS water quality modeling efforts will more accurately reflect the steps agricultural producers have and are taking to decrease the amount of NPS pollution reaching water bodies. Additionally, policy regarding NPS pollution and BMPs should reflect the apparent equal qualities of cost-share and non cost-share practices. The assessment tools developed as a part of this study can potentially be applied to determine the quality of BMPs on basin or state-wide scales to give policy makers a better understanding of the practices and populations that the policies are created for. Moreover, BMP quality scores have the potential to be used as a surrogate measure for BMP performance. Further research recommendations include correlating BMP quality scores with BMP performance, wider scale testing of the tools, continued revision of the tools, and using the assessment tool scores to diagnose BMP quality problems.
Master of Science

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Alvarado, Lizeth, Juan Díaz, Juan Quiroz, and Carlos Raymundo. "Basic production planning and control model based on process management to increase the productivity of mango MSEs in Casma." Springer Verlag, 2020. http://hdl.handle.net/10757/656119.

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El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.
The department with the greatest economic dependence on the fruit is Ancash, and the Province of Casma is most important in production, as it only produces mango; however, at the productivity level, is a marked difference of 8.2 t/ha compared to the highest worldwide producer, Mexico. Taking this data into consideration, an analysis of the MSEs producing mango in Casma was conducted and problems were seen in the management of resources and processes, both at the levels of planning and control. Considering the problems of MSEs from Casma, a basic Production Planning and Control model was designed based on Process Management and agricultural best practices. The model consists of applying process management tools, such as the flow diagram, the SIPOC turtle, data sheet indicators, procedures, and formats for each sub-process, all with the aim of better understanding the proposal’s development and increasing the productivity of MSEs.

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Kumar, Vivek. "Hydro-Physical Characterization of Media Used in Agricultural Systems to Develop the Best Management Practices for operation of an Environmentally Sustainable Agricultural Enterprise." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/787.

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Florida is the second leading horticulture state in the United States with a total annual industry sale of over $12 Billion. Due to its competitive nature, agricultural plant production represents an extremely intensive practice with large amounts of water and fertilizer usage. Agrochemical and water management are vital for efficient functioning of any agricultural enterprise, and the subsequent nutrient loading from such agricultural practices has been a concern for environmentalists. A thorough understanding of the agrochemical and the soil amendments used in these agricultural systems is of special interest as contamination of soils can cause surface and groundwater pollution leading to ecosystem toxicity. The presence of fragile ecosystems such as the Everglades, Biscayne Bay and Big Cypress near enterprises that use such agricultural systems makes the whole issue even more imminent. Although significant research has been conducted with soils and soil mix, there is no acceptable method for determining the hydraulic properties of mixtures that have been subjected to organic and inorganic soil amendments. Hydro-physical characterization of such mixtures can facilitate the understanding of water retention and permeation characteristics of the commonly used mix which can further allow modeling of soil water interactions. The objective of this study was to characterize some of the locally and commercially available plant growth mixtures for their hydro-physical properties and develop mathematical models to correlate these acquired basic properties to the hydraulic conductivity of the mixture. The objective was also to model the response patterns of soil amendments present in those mixtures to different water and fertilizer use scenarios using the characterized hydro-physical properties with the help of Everglades-Agro-Hydrology Model. The presence of organic amendments helps the mixtures retain more water while the inorganic amendments tend to adsorb more nutrients due to their high surface area. The results of these types of characterization can provide a scientific basis for understanding the non-point source water pollution from horticulture production systems and assist in the development of the best management practices for the operation of environmentally sustainable agricultural enterprise

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Helling, Alexander Paul. "Sustainable Agriculture in Vermont: Economics of Climate Change Best Management Practices and the Complexity of Consumer Perceptions of Raw Milk." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/437.

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Changing weather patterns, the declining social fabric of rural communities, and economic uncertainty increasingly pose challenges to Vermont communities. The socially and environmentally embedded production practices within sustainable agriculture present a potential solution to these problems. In order to make the most of the potential benefits of these practices society must maximize their adoption. This requires an understanding of both farmer adoption of these practices and consumer perceptions of the resulting food products. This thesis contributes two original articles on sustainable agriculture through the analysis of factors driving both farmer adoption and consumer perceptions of products and practices often thought of as sustainable. The first article seeks to understand farmer adoption of climate change best management practices (CCBMPs). Farmer perceptions of risk and profitability of best management practices (BMPs) are key determinants of adoption, which traditional incentive programs like the Environmental Quality Incentives Program (EQIP) attempt to address by providing financial and technical support. To ensure appropriate price points are offered through these programs, regional price structures must be based upon locally established costs. Thus, this article focuses on the economic cost of implementing and maintaining CCBMPs for twelve diverse farms in Vermont. Specifically, three CCBMPs for Vermont are examined: cover cropping, management intensive rotational grazing (MIRG), and riparian buffer strips. Results of a yearlong farmer based data collection process indicate that the average cost for cover cropping is $129.24/acre, for MIRG is $79.82/acre, and for a tree based riparian buffer strip is $807.33/acre. We conclude that existing incentive payments for cover cropping and MIRG are below costs, likely resulting in under-adoption. The second article reports on a study which seeks to understand the factors influencing Vermont consumer perceptions of raw milk safety. While this article makes no assertion regarding the sustainability of raw milk, an association is established between the motivations for raw milk consumption and sustainable agriculture support. Vermonterâ??s appear to be continuing the trend of consuming raw milk at an increasing rate despite continued declarations from local and national public health officials that raw milk is too microbiologically dangerous to justify its consumption. Thus this study was designed to increase understanding of the factors driving consumer perceptions of raw milk safety. A conceptual model was developed to establish potential factors and related questions were incorporated into the 2014 Vermonter Poll. Resulting data were analyzed using a Probit regression analysis. We conclude that observable factors have the greatest influence on perceptions of raw milk safety. Specifically, perceived health benefits, presence of children in the household, and taste all influence perceptions of raw milk safety.

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Dittmer, Kyle Michael. "Mitigating Gaseous Nitrogen and Carbon Losses from Northeastern Agricultural Soils via Alternative Soil Management Practices." ScholarWorks @ UVM, 2019. https://scholarworks.uvm.edu/graddis/1161.

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Traditional agricultural practices often result in gaseous losses of nitrous oxide (N2O), ammonia (NH3), and carbon dioxide (CO2), representing a net loss of nutrients from agricultural soils, which negatively impacts crop yield and requires farmers to increase nutrient inputs. By adopting best management practices (BMPs; i.e., no-tillage, cover crops, sub-surface manure application, and proper manure application timing), there is great potential to reduce these losses. Because N2O and CO2 are also greenhouse gases (GHGs), climate change mitigation via BMP adoption and emissions reductions would be an important co-benefit. However, adopting a no-tillage and cover cropping system has had setbacks within the Northeast, primarily due to concerns regarding manure nitrogen (N) losses in no-tillage systems as well as uncertainty surrounding the benefits of cover crops. This thesis used two field-trials located in Alburgh, Vermont to assess differences in (i) GHG emissions from agricultural soils, (ii) nitrate and ammonium retention, (iii) corn yield and protein content, and (iv) N uptake and retention via cover crop scavenging under a combination of different BMPs. Chapter 1 evaluates the effects of different reduced-tillage practices and manure application methods (i.e., vertical-tillage, no-tillage, manure injection, and broadcast manure application) on reducing N2O and CO2 emissions, retaining inorganic N, and improving crop yields. Greenhouse gas measurements were collected every other week for the growing season of 2015-2017 via static chamber method using a photoacoustic gas analyzer. Results from this study showed that tillage regimes and manure application method did not interact to affect any of the three research objectives, although differences between individual BMPs were observed. Notably, vertical tillage enhanced CO2 emissions relative to no-tillage, demonstrating the role of soil disturbance and aeration on aerobic microbial C transformations. Manure injection was found to significantly enhance both N2O and CO2 emission relative to broadcast application, likely due to the formation of anerobic micro-zones created from liquid manure injection. However, plots that received manure injection retained greater concentrations of soil nitrate, a vital nutrient for quality crop production, thereby highlighting a major tradeoff between gaseous N losses and N retention with manure injection. Chapter 2 evaluates the effects of tillage practices and timing of manure application to increase N retention with the use of cover crops in order to mitigate GHG emissions, enhance soil nitrate and ammonium retention, and improve cropping system N uptake. Treatments at this field trial consisted of a combination of the presence or absence of cover crops, no-tillage or conventional-tillage, and spring or fall manure application. Greenhouse gas emissions were measured every other week via static chamber method using a gas chromatograph for the growing season of 2018. Results from this study showed that the presence of cover crops enhanced both N2O and CO2 emissions relative to fallow land, irrespective of tillage regime and manure application season, likely as a result of greater N and carbon substrates entering the soil upon cover crop decomposition. Due to enhanced N2O emissions with cover crops, cover crops did not retain significantly greater inorganic N in the system upon termination.

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Noteboom, Matthew. "Impacts of Deforestation on Water Quality and Quantity in a Canadian Agricultural Watershed." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40967.

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Around the world, many forested areas have been and continue to be cleared for expanding agriculture. Canada’s remaining forested lands account for around 9% of the world’s forest cover. Although only a fraction is lost to deforestation annually (0.02%, 2013), Statistics Canada reports that conversion to agriculture is the most significant driver of forest loss. As climate changes and agricultural demand expands, this trend is expected to continue, and ecosystems will continue to be impacted by resulting habitat loss and hydrological changes that can impact infrastructure and communities. Additionally, changes to sediment and nutrient loadings can harm ecosystems and affect the downstream usability of freshwater supplies. The impact of increased sediment and nutrient concentrations in freshwater systems has been extensively documented in the literature. In some extreme cases, it can lead to anoxic ‘dead zones’ in riverine, lacustrine, and marine habitats. Many river systems in Canada have shown elevated nutrient levels in recent years, often tied to the expansion of agricultural land use and destruction of natural forests to increasing nutrient levels in downstream rivers, lakes, and oceans. This study applies numerical modelling to quantify the influence of forest loss, agricultural expansion and the application of best management practices (BMPs) on water quality and quantity in the South Nation Watershed in eastern Ontario, Canada. The land use in the watershed is mainly agricultural (over 60%) with forest (27%) that is unevenly distributed in the basin. Aerial photography surveys from 2008 and 2014 show a steady decline in forest cover. Recent water quality monitoring has shown nutrient concentrations at or above Canadian water quality standards in many parts of the basin. The Soil and Water Assessment Tool (SWAT) was used to model the watershed because of its capacity to simulate comprehensive land management scenarios and assess their impact on a variety of water quantity and parameters quickly and effectively. The work was performed in four steps: 1. Recent land use configurations (2008-2014) in the watershed were acquired, and simplified land use projections based on the direct substitution of cropland for forest land were developed. 2. A numerical model was calibrated and validated for the initial land use scenario. 3. These land use scenarios, as well as more hypothetical scenarios representing more extensive deforestation and reforestation, were used as the basis for hydrological modelling using 31 years of real-world meteorological observations. 4. Idealized vegetated filter strips (VFSs) and grassed waterways (GWWs) were added to the cropped land packages to study the potential of these practices to contribute to the management of water quality. Analysis of the 33 output datasets derived from simulations of the suite of land use scenarios with and without VFSs and GWWs leads to several conclusions, while also raising some questions. Generally, forests significantly reduce sediment, nitrate and phosphorus outputs to streams as well as slightly reducing water yield compared to cropped areas due to an increase in surface runoff, groundwater and lateral flow combined with the absence of tile drainage. Across subbasins, this translates to significant reductions in sediment, nitrate and total phosphorus loadings entering the river reaches and a slight increase in water yield. At the basin outlet near Plantagenet, Ontario, streamflow and sediment loading show to have little sensitivity to changes in forest and crop cover, while increased forest cover leads to significantly reduced nutrient loadings, particularly in late spring and early winter. It is clear from this work that continued deforestation will continue to drive further nutrient enrichment in the South Nation River, while VFSs seems to have a significant potential for offsetting some of this enrichment. Streamflow and sediment loadings, however, are not significantly impacted by foreseeable deforestation. The influence of land use change and BMPs was much more significant in the runoff than in exports from the basin, suggesting there would be value in further examination of water quality and quantity at a higher spatial density to expand on assumptions of in-stream processes made here.

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Rees, Gwendolen Jayne. "Two analyses of costs of agricultural NPS pollution: Transactions costs of expanding nutrient trading to agricultural working lands and Impacts of TCs and differential BMP adoption rates on the cost of reducing agricultural NPS pollution in Virginia." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/52939.

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For over 30 years, federal and state governments have been engaged in a collective effort to improve the water quality and living resources in the Chesapeake Bay (CB), focusing particularly on reducing delivered nitrogen and phosphorus loads. However, achievement of water quality objectives remains elusive. In Virginia, agriculture represents the single largest source of nutrient loads to the Chesapeake Bay. Despite aggressive regulatory efforts in other nutrient source sectors, state authorities rely on educational programs and voluntary financial assistance programs to induce landowners to adopt best management practices (BMPs) that reduce agricultural nutrient loads. This study explores two economic aspects of efforts to reduce agricultural nonpoint source (NPS) pollution in the Virginia portion of the CB watershed. Firstly, current and possible future transactions costs associated with specific aspects of agricultural NPS participation in water quality trading (WQT) programs are examined in Chapter 1. A case study approach is used to consider the possible cost consequences of expanding the use of NPS credits from agricultural 'working lands' BMPs in Virginia. Findings indicate that overall transactions costs for nutrient trades involving agricultural NPS in Virginia are currently relatively low, due to the type of activities being credited: simple land conversions. Based on best available evidence, the administrative transactions costs of creating credits on agricultural 'working lands' using management and structural BMPs will be 2 to 5 times more costly on a per project basis than for credits generated from land conversions. Compliance monitoring protocols were found to be a significant driver of costs for credits generated from working agricultural lands. These results suggest an important cost/risk tradeoff between verification cost and compliance certainty for program designers to consider. The second study (Chapter 2) considers the economic cost of meeting pollution reduction targets for the Virginia portion of the CB Watershed. Existing cost models are based on simplifying behavioral assumptions about public transactions costs, conservation adoption rates, and implementation costs of agricultural BMPs. This study builds on the existing literature and uses the estimates of transactions costs from Chapter 1 together with information on producer BMP adoption rates to examine the implications of including transactions costs and differential BMP costs and adoption rates when estimating the minimum costs of achieving specified nutrient reduction goals in Virginia. The paper uses a cost-minimizing mathematical programming approach and models a number of different cost scenarios. Results indicate that inclusion of transactions costs substantially affects estimates of total costs of meeting nutrient reduction goals; on average total costs increased by 44 percent, but ranged between 19 and 81 percent depending on the scenario analyzed. Analysis of the modelled scenarios shows that those BMPs that account for the most implementation costs do not necessarily account for the most transactions costs (and vice versa). This suggests that transactions costs should be acknowledged to vary with the type of practices being implemented, rather than being approximated as either a fixed amount or a fixed proportion of implementation costs. In addition, the analysis highlights the disproportionate costs associated with achieving nutrient reductions via high-cost adopters, and suggests there may be a role for education or extension to assist landholders to lower opportunity costs of participating in conservation.
Master of Science

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Spangler, Jonathan Travis. "An Assessment of Floating Treatment Wetlands for Reducing Nutrient Loads from Agricultural Runoff in Coastal Virginia." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/86656.

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Floating treatment wetlands (FTWs) are an innovative best management practice that can enhance the performance of traditional retention ponds by increasing removal of the nutrients nitrogen (N) and phosphorous (P). FTWs consist of floating rafts on which wetland plants are planted, allowing the roots to be submerged below the water surface while the shoots remain above. A growing body of research has documented FTW performance with regard to urban runoff treatment, however evaluation of FTW effectiveness for treatment of agricultural runoff has received less attention. Due to high fertilization and irrigation rates, commercial nursery runoff contains much higher concentrations of N and P than runoff from urban areas. We conducted this study over two growing seasons (2015 and 2016) to assess the effectiveness of FTWs for use in commercial nursery retention ponds. In the first study we used two different nutrient concentrations, one to simulate nursery runoff (17.1 mg∙L-1 TN and 2.61 mg∙L-1 TP) and one to simulate concentrations that fall between urban and nursery runoff (5.22 mg∙L-1 TN and 0.52 mg∙L-1 TP). Four treatments were used: 1) Pontederia cordata planted in cups supported by a Beemat, 2) Juncus effusus planted in cups supported by a Beemat, 3) a Beemat with no plants, and 4) no treatment (open-water). Performance was evaluated based on a 7-day hydraulic retention time (HRT). Pontederia cordata removed between 90.3% and 92.4% of total phosphorus (TP) and 84.3% and 88.9% total nitrogen (TN), depending on initial loads. These reductions were significantly more than other treatments at both high and low nutrient loading rates. Juncus effusus performed better than the control treatments for TP removal at low nutrient concentrations, but did not perform any better than the control at higher nutrient loads. In the second study, conducted in 2016, we evaluated different plant species over two 8-week trials using simulated nursery runoff. We used five monoculture FTWs with the following species: Agrostis alba, Canna ×generalis, Carex stricta, Iris ensata, and Panicum virgatum. Additionally, two treatments were created from mixed species plantings and the final treatment consisted of an open water control mesocosm. Nutrient removal performance was evaluated over a 7-day HRT. P removal (phosphate-P) by FTW treatments ranged from 26.1% to 64.7% for trial 1 and 26.8% to 63.2% for trial 2. Trial 1 N removal (sum of ammonium-N, nitrate-N, and nitrite-N) efficiencies ranged from 38.9% to 82.4%, and trial 2 ranged from 12.9% to 59.6%. Panicum virgatum removed significantly more N and P than the control and any other FTW treatment in the second study. Both studies indicated, depending upon plant species, that FTWs can effectively remove nitrogen and phosphorous from urban and commercial nursery retention ponds.
Master of Science

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Zhong, Hua. "ESSAYS ON FARMER WILLINGNESS TO PARTICIPATE IN BEST MANAGEMENT PRACTICES IN THE KENTUCKY RIVER WATERSHED." UKnowledge, 2016. http://uknowledge.uky.edu/agecon_etds/40.

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This dissertation explores the adoption of Best Management Practices (BMPs) in the Kentucky River watershed. Through a survey of farmers in the Kentucky River watershed, chapter two investigates farmers’ current BMP adoption and their willingness to engage in additional adoption incentivized through a proposed Water Quality Trading (WQT) program. This chapter includes two parts: the first part is to investigate the factors influencing farmers’ current usage of BMPs; the second part is to estimate farmers’ willingness to implement BMPs given different levels of compensation specified in the survey. Farmers’ experiences about BMPs are more likely to persuade them to adopt additional BMPs. The activities of using riparian buffers, fencing off animals and building up waste storage facilities are found to be responsive to the levels of compensation offered. The third chapter discusses farmers’ expected economic benefits from BMP adoption, and addresses the missing data issue. In the survey, of those respondents who indicated that they accept the offered level of compensation, about 20% of them did not answer the follow-up question of how much they would adopt the practice, creating missing data. We compare three methods to handle the issue of missing data: deletion method, mean imputation, and multiple imputation method. Following these methods, we estimate factors affecting how much farmers may engage in BMPs using a Tobit or Poisson model. The results show that increasing the compensation for using BMPs is more likely to encourage farmers to adopt riparian buffers. Results obtained using the method of multivariate imputation by chained equation are more promising than using the deletion or mean imputation method. The fourth chapter examines whether wealth change and local community interaction may affect BMP adoption. Survey data on BMP adoption are combined with the local community data from publically available sources. Results show that the decrease in land values between 2007 and 2012 discouraged the adoption of riparian buffers; the equine inventory in local communities has positive impact on the adoption of animal fences and nutrient management; the more rural the local communities are, the less likely farmers would fence off livestock from water resources.

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Powell, George Erick. "Examination, application, and evaluation of geomorphic principles and resulting water quality in Midwest agricultural streams and rivers." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1148992105.

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Burnett, Elizabeth Anne. "The Influence of Farmer Stress and Hardiness on Adoption of Best Management Practices in the Maumee Watershed." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1405694911.

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Twombly, Cameron Robert. "Edge-of-Field Hydrology and Nutrient Fluxes within Northeastern Agroecosystems: Evaluation of Alternative Management Practices and Water Quality Models." ScholarWorks @ UVM, 2019. https://scholarworks.uvm.edu/graddis/1170.

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Agricultural runoff is one of largest contributors of phosphorus (P), nitrogen (N), and sediment affecting freshwater systems in watersheds across the Northeastern U.S., including the Lake Champlain Basin in Vermont. Agricultural cropping systems, such as corn silage and haylands, used for dairy feed production have been shown to impact watershed hydrology and water quality. Agricultural best management practices (BMPs) have the potential to decrease runoff volumes and flow rates and the associated export of nutrients and sediment from agricultural fields. Many states in the Northeastern U.S., including Vermont, are beginning to require farmers to implement water quality BMPs and further improve risk evaluation of export of P in runoff using evolving P site assessment tools, such as the Phosphorus Index (P-Index). Quantifying the effects of BMPs on hydrologic and nutrient exports from fields is critical for informing site assessment tools that aid in the development of nutrient management plans and to help design agroecosystems that do not degrade water quality. However, there is a lack of data on the effects of BMPs on edge-of-field hydrologic and nutrient fluxes, especially in cold-climate regions with snow-melt induced runoff events. This thesis consists of four chapters, Chapter 1 is a comprehensive literature review on agricultural hydrology and water quality, BMP effectiveness, and P site assessment tools. Chapters 2 and 3 address research objectives related to the evaluation of BMP and P site assessment tool effectiveness. Chapter 4 is a summary of the conclusions drawn from the work done in Chapters 2 and 3, and suggestions for future work. Chapter 2 evaluates the effects of soil aeration prior to manure application on edge-of-field hydrology, water quality, and P fluxes in haylands with clay soils during both precipitation and snow-melt induced runoff events. Edge-of-field water quality monitoring techniques and passive-capillary lysimeter systems were used to continuously measure the losses of surface runoff, subsurface leachate, and the associated export of nutrients (total phosphorus, total dissolved phosphorus, total nitrogen, and total dissolved nitrogen) and total suspended solids resulting from runoff events year-round from 2012 to 2018. Annual P fluxes in the form of vegetative uptake and removal, manure additions, and soil test P were also recorded. Results from this study indicated that soil aeration had the potential to reduce nutrient and sediment exports from haylands with poorly-drained, high runoff producing soils in the Northeastern U.S. where winter freeze-thaw conditions exist. However, potential increases in surface and subsurface hydrologic flows can accompany these reductions; these implications should be considered before implementation. Chapter 3 identifies potential P-Index improvements through the representation of topographic controls on phosphorus (P) transport by comparing results from the Vermont P-Index (VT P-Index) and a more complex process-based model, TopoSWAT, across topographic regions in a small agricultural watershed (360 ha) in the Lake Champlain Basin. Scenarios of varying P management strategies were modeled for corn silage production fields with poorly-drained soils and rolling topography. Modeled outputs of P risk assessments and edge-of-field dissolved and particulate P losses were compared. Results from this study suggest that the VT P-Index could improve its ability to support farm nutrient management planning and other P-based management decisions by incorporating topographic controls of runoff production into its estimation of P transport.

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Taniwaki, Ricardo Hideo. "Effects of intensive agriculture in the structure and functioning of tropical headwater streams." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-15082016-133412/.

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Tropical regions hold the planet´s most biodiverse ecosystems. Despite its importance to biodiversity and conservation, anthropogenic activities are degrading these ecosystems, with unknown consequences for its functioning and structure. In between the several ecosystems through the tropics, freshwater ecosystems call attention, due to its small fraction of area comparing to terrestrial ecosystems, that represent an enormous importance for human surviving and developing. Headwater streams constitute the majority of water bodies in a catchment, and therefore, it is essential for the health of the entire freshwater ecosystems. Several headwater streams are inserted in agricultural lands, suffering from the pressures from agricultural intensification. Therefore, this thesis was developed aiming to understand what are the main pressures that tropical headwater streams has been suffering, worldwide and locally in the Corumbataí river basin. The first chapter will contribute to understanding what are the main issues that tropical streams have been experiencing, focusing on agricultural multiple stressors and climate change effects. The second chapter analyzes how the conversion of low-intensity pasturelands to high-intensity bioenergy crops changes the water quality parameters in streams located in the Corumbataí river basin and also examines how important are the riparian forests in the headwater zone to provide better water quality in bioenergy crops. The third chapter investigates how water quality and climatic characteristics affect benthic biofilm community dynamics in tropical headwater streams in the Corumbataí river basin. The results have shown the existence of several knowledge gaps about tropical streams, mainly related to the effects of climate change, multiple stressors and the lack of policies and mitigation strategies for climate change. In relation to water quality, we found that the conversion of low-intensity pastures to high-intensity bioenergy crops are degrading water quality. Riparian forests in the springhead zone have demonstrated to be essential in providing water quality in bioenergy crops, especially in the wet season. The benthic biofilm community seems to be controlled mainly by climate characteristics and not by nutrient availability as observed in temperate streams. Therefore, a climate change scenario, the benthic biofilm will be strongly affected, with consequences in the functioning of tropical headwater streams. To reduce the negative impacts of intensive agriculture and climate change, we recommend the implementation of riparian forests, with special attention to the springhead area and also the implementation of best agricultural practices in tropical agriculture to ensure the sustainability of tropical freshwater resources.
As regiões tropicais possuem os ecossistemas mais biodiversos do planeta. Apesar da sua importância na manutenção da biodiversidade, as atividades antrópicas estão degradando esses ecossistemas, gerando consequências negativas para sua estrutura e funcionamento. Entre os diversos ecossistemas tropicais, as águas doces chamam a atenção por ocupar uma pequena área em comparação com ecossistemas terrestres, porém, representam grande importância para a sobrevivência e desenvolvimento humano. Os riachos de cabeceira representam a maior parte dos corpos aquáticos em uma microbacia e, portanto, sua conservação é essencial para a saúde de toda a rede de drenagem de água doce. Diversos riachos de cabeceira estão inseridos em ecossistemas agrícolas, sofrendo as consequências da agricultura intensiva. Nesse sentido, esta tese foi desenvolvida com o intuito de entender quais são os principais impactos que os riachos de cabeceira tropicais vêm sofrendo, globalmente e localmente na bacia do rio Corumbataí (SP, Brasil). O primeiro capítulo contribui para entender quais os principais problemas que riachos tropicas estão sofrendo, focando nos múltiplos estressores advindos da agricultura e efeitos de mudanças climáticas. O segundo capítulo analisa como a conversão de pastos para cultivo de cana de açúcar modifica a qualidade da água em riachos da bacia do rio Corumbataí e também analisa o quão fundamentais são as florestas nas áreas de nascente para manter a qualidade da água em plantios de cana de açúcar. O terceiro capítulo analisa como a qualidade da água e características climáticas influenciam biofilmes bentônicos em riachos de cabeceira na bacia do rio Corumbataí. Os resultados demonstraram a existência de diversos tópicos que necessitam de maior entendimento, principalmente relacionados às mudanças climáticas e estressores múltiplos e a falta de políticas e estratégias de mitigação para os efeitos de mudanças climáticas. Em relação à qualidade da água, demonstrou-se que a conversão de pastos para cultivo de cana de açúcar reduz a qualidade da água. A presença de florestas nas nascentes demonstrou ser essencial na manutenção da qualidade da água em plantios de cana. Os biofilmes bentônicos demonstraram ser controlados principalmente por características sazonais e não pela disponibilidade de nutrientes como observado em riachos temperados. Portanto, essa comunidade será severamente afetada diante das mudanças climáticas, com consequências no funcionamento de riachos de cabeceira tropicais. Para reduzir os efeitos negativos da agricultura intensiva e das mudanças climáticas, recomenda-se a implementação de florestas ripárias, com especial atenção às áreas de nascentes. Também se recomenda a implementação de boas práticas agrícolas na agricultura para garantir a sustentabilidade dos recursos hídricos tropicais.

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Bal, Sucheta. "Urban Agriculture / Community Gardening: Starting and Maintaining Successful Programs." Cincinnati, Ohio : University of Cincinnati, 2009. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1242870589.

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Thesis (Master of Community Planning)--University of Cincinnati, 2009.
Advisor: Carla Chifos. Title from electronic thesis title page (viewed July 29, 2009). Includes abstract. Keywords: urban agriculture; community gardening; community development; best practices; programming. Includes bibliographical references.

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Wagena, Moges Berbero. "Quantifying the Impact of Climate Change on Water Availability and Water Quality in the Chesapeake Bay Watershed." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/82420.

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Climate change impacts hydrology, nutrient cycling, agricultural conservation practices, and greenhouse gas (GHG) emissions. The Chesapeake Bay and its watershed are subject to the largest and most expensive Total Maximum Daily Load (TMDL) ever developed. It is unclear if the TMDL can be met given climate change and variability (e.g., extreme weather events). The objective of this dissertation is to quantify the impact of climate change and climate on water resources, nutrient cycling and export in agroecosystems, and agricultural conservation practices in the Chesapeake Bay watershed. This is accomplished by developing and employing a suite of modelling tools. GHG emissions from agroecosystems, particularly nitrous oxide (N2O), are an increasing concern. To quantify N2O emissions a routine was developed for the Soil and Water Assessment Tool (SWAT) model. The new routine predicts N2O and di-nitrogen (N2) emissions by coupling the C and N cycles with soil moisture, temperature, and pH in SWAT. The model uses reduction functions to predict total denitrification (N2 + N2O production) and partitions N2 from N2O using a ratio method. The SWAT nitrification routine was modified to predict N2O emissions using reduction functions. The new model was tested using GRACEnet data at University Park, Pennsylvania, and West Lafayette, Indiana. Results showed strong correlations between plot measurements of N2O flux and the model predictions for both test sites and suggest that N2O emissions are particularly sensitive to soil pH and soil N, and moderately sensitive to soil temperature/moisture and total soil C levels. The new GHG model was then used to analyze the impact of climate change and extreme weather conditions on the denitrification rate, N2O emissions, and nutrient cycling/export in the 7.4 km2 WE38 watershed in Pennsylvania. Climate change impacts hydrology and nutrient cycling by changing soil moisture, stoichiometric nutrient ratios, and soil temperature, potentially complicating mitigation measures. To quantify the impact of climate change we forced the new GHG model with downscaled and bias-corrected regional climate model output and derived climate anomalies to assess their impact on hydrology, nitrate (NO3-), phosphorus (P), and sediment export, and on emissions of N2O and N2. Model-average (± standard deviation) results indicate that climate change, through an increase in precipitation, will result in moderate increases in winter/spring flow (2.7±10.6 %) and NO3- export (3.0±7.3 %), substantial increases in dissolved P (DP, 8.8±19.8 %), total P (TP, 4.5±11.7 %), and sediment (17.9±14.2 %) export, and greater N2O (63.3±50.8 %) and N2 (17.6±20.7 %) emissions. Conversely, decreases in summer flow (-12.4±26.7 %) and the export of P (-11.4±27.4 %), TP (-7.9±24.5 %), sediment (-4.1±21.4 %), and NO3- (-12.2±31.4 %) are driven by greater evapotranspiration from increasing summer temperatures. Increases in N2O (20.1±29.3 %) and decreases in N2 (-13.0±14.6 %) are also predicted in the summer and driven by increases in soil moisture and temperature. In an effort to assess the impact of climate change at a regional level, the model was then scaled-up to the entire Susquehanna River basin and was used to evaluate if agricultural best management practices (BMPs) can offset the impact of climate change. Agricultural BMPs are increasingly and widely employed to reduce diffuse nutrient pollution. Climate change can complicate the development, implementation, and efficiency of BMPs by altering hydrology, nutrient cycling, and erosion. We select and evaluate four common BMPs (buffer strips, strip crop, no-till, and tile drainage) to test their response to climate change. We force the calibrated model with six downscaled global climate models (GCMs) for a historic period (1990-2014) and two future scenario periods (2041-2065) and (2075-2099) and quantify the impact of climate change on hydrology, NO3-, total N (TN), DP, TP, and sediment export with and without BMPs. We also tested prioritizing BMP installation on the 30% of agricultural lands that generate the most runoff (e.g., critical source areas-CSAs). Compared against the historical baseline and excluding the impact of BMPs, the ensemble model mean (± standard deviation?) predictions indicate that climate change results in annual increases in flow (4.5±7.3%), surface runoff (3.5±6.1%), sediment export (28.5±18.2%) and TN (9.5±5.1%), but decreases in NO3- (12±12.8%), DP (14±11.5%), and TP (2.5±7.4%) export. When agricultural BMPs are simulated most do not appreciably change the overall water balance; however, tile drainage and strip crop decrease surface runoff generation and the export of sediment, DP, and TP, while buffer strips reduced N export substantially. Installing BMPs on critical source areas (CSAs) results in nearly the same level of performance for most practices and most pollutants. These results suggest that climate change will influence the performance of BMPs and that targeting BMPs to CSAs can provide nearly the same level of water quality impact as more widespread adoption. Finally, recognizing that all of these model applications have considerable uncertainty associated with their predictions, we develop and employ a Bayesian multi-model ensemble to evaluate structural model prediction uncertainty. The reliability of watershed models in a management context depends largely on associated uncertainties. Our Objective is to quantify structural uncertainty for predictions of flow, sediment, TN, and TP predictions using three models: the SWAT-Variable Source Area model (SWAT-VSA), the standard SWAT model (SWAT-ST), and the Chesapeake Bay watershed model (CBP-model). We initialize each of the models using weather, soil, and land use data and analyze outputs of flow, sediment, TN, and TP for the Susquehanna River basin at the Conowingo Dam in Conowingo, Maryland. Using these three models we fit Bayesian Generalized Non - Linear Multilevel Models (BGMM) for flow, sediment, TN, and TP and obtain estimated outputs with 95% confidence intervals. We compare the BGMM results against the individual model results and straight model averaging (SMA) results using a split time period analysis (training period and testing period) to assess the BGMM in a predictive fashion. The BGMM provided better predictions of flow, sediment, TN, and TP compared to individual models and the SMA during the training period. However, during the testing period the BGMM was not always the best predictor; in fact, there was no clear best model during the testing period. Perhaps more importantly, the BGMM provides estimates of prediction uncertainty, which can enhance decision making and improve watershed management by providing a risk-based assessment of outcomes.
Ph. D.

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Woida, Angela. "Best Management Practices-A Practical Way to Protect the Environment." College of Agriculture, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/295729.

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Wiltshire, Serge William. "Grass-Based Dairy in Vermont: Benefits, Barriers, and Effective Public Policies." ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/492.

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A comprehensive literature review was undertaken in order to define and assess the sustainability and resiliency characteristics associated with grass-based and confinement dairy farming. Primarily as a result of reduced input costs, grass-based dairy farming often enhances profitability over confinement systems, especially on small farms. Further, conversion of tilled soil to permanent pasture has been shown to significantly reduce harmful sediment and nutrient transport into waterways. Perennial forage also acts as a carbon sink, curtailing or even negating a grass-based farm's carbon footprint. Finally, social benefits derived from enhanced nutrition and higher quality of life are also associated with grass-based dairy farming. Given that policy goals of the State of Vermont include both bolstering farm viability and reducing farm-related runoff, two questions are then raised. What is the most effective way to incentivize the adoption of rotational grazing in Vermont? And what types of farms are best suited to its use? A series of interviews with dairy experts and farmers was conducted as a preliminary investigation into these questions. This qualitative evidence suggested that farmers generally adopted grass-based dairying after observing a peer's success with the method, suggesting that a key leverage point may be peer-based learning. A behavioral economics game was developed to evaluate the role of peer networks in facilitating decision-making under conditions of uncertainty. A computerized game platform simulated networks of small dairy farm enterprises, with participants acting as farm managers. Treatments varied the size of peer networks, as well as the inclusion of a perfectly-performing automated 'seed player.' Participants could base their decisions upon the successes of their peers. They received a cash incentive based on their farms' performance. Results indicated that players with higher numbers of peers made better economic decisions on average. The inclusion of a 'seed player' within a network, which modeled the ideal behavior, also facilitated better decision-making. Both of these correlations were statistically significant. Furthermore, the shape of the 'diffusion curve' of new adoptees confirmed literature on the dynamics of innovation diffusion. Public policy implications from this work include an increased focus on facilitating peer-to-peer learning among farmers where Best Management Practice adoption is a policy goal. To further evaluate the potential for peer learning to facilitate positive change, the Dairy Farm Transitions Agent Based Model (DFTABM) was developed. The model was calibrated using existing datasets along with the qualitative and quantitative results described above. It forecasts effects on farm profitability, attrition, and soil loss arising from varying assumptions about peer network connectivity, peer emulation, macroeconomic trends, and agri-environmental policy. Nine experimental treatments were assessed. Overall, it was found that high rates of emulation coupled with high rates of connectivity'especially targeted connectivity among smaller farms'yielded the best balance of farm viability and reduction in soil loss. The establishment of a performance-based tax credit had no clear correlation with the resulting soil loss figures predicted by the model. Policy implications from this study include the finding that direct payment schemes for reduction in environmental harm may not always have their intended effects, whereas policies that enhance peer-to-peer learning opportunities, especially among the proprietors of smaller farms, may present an effective and relatively affordable means by which to bolster farm profitability while also reducing environmental degradation.

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D'Ambrosio, Jessica Leigh. "Perspectives on the Geomorphic Evolution and Ecology of Modified Channels and Two-Stage Ditches in the Agriculturally-Dominated Midwestern United States." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1356038774.

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Cohen, Rachel L. "Urban Agriculture Stormwater Management in California Cities." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1015.

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Cities within California are beginning to incorporate urban agriculture into their land use designations. Prompted by residents and local organizations, cities are hoping to capture the benefits that urban agriculture provides. Research has shown that urban agriculture renews and beautifies neighborhoods, provides healthy food choices, increases public health, has the potential to help with stormwater runoff, creates jobs, and fosters community. In the last few years, several California cities have made headlines as they have adopted new zoning codes that include urban agriculture. In reviewing these new zoning codes and exploring the topic of urban agriculture, it became evident that just because an urban farm was small, organic and provided certain benefits that it was not free from impacting its surroundings. As more urban agricultural ventures are established within cities, planners have to carefully consider their effect. One such impact could be stormwater pollution. There is insufficient research to determine whether there is a relationship between urban agriculture and stormwater, however, studies on conventional agriculture and urban landscaping (mainly urban lawns) show that each of these areas pollute the local water bodies with sediment, chemicals, and nutrients. Is urban agriculture different? This thesis utilizes two case studies within California, the City of Oakland and the City of San Diego, to examine the similarities and differences between each city’s urban agriculture ordinances and evaluate whether or not the cities have adjusted stormwater requirements in parallel with these ordinances. Interview responses and site visits in each city were analyzed and compared to expound upon the approaches each city engaged. Using the collected data and analysis as a base, a set of guidelines was created for managing stormwater runoff from urban agriculture.

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Thompson, Thomas L., Scott A. White, and Michael A. Maurer. "Development of Best Management Practices for Fertigation of Young Citrus Trees." College of Agriculture, University of Arizona (Tucson, AZ), 2000. http://hdl.handle.net/10150/223854.

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Microsprinkler irrigation offers excellent flexibility for site-specific management of water and nitrogen inputs for citrus orchards in the southwestern United States. Escalating water costs, declining water availability, and increasing regulation of nitrogen (N) fertilizer use are causing growers to adopt practices to improve water and N use efficiency. 'Newhall' navels on 'Carrizo' rootstock were planted in Jan. 1997 and an experiment was initiated. This experiment was continued during 1999. The objective of the experiment was to develop appropriate management guidelines for N fertigation of 3-4 year old microsprinkler-irrigated navel orange trees. Treatments were factorial combinations of three N rates (0.15, 0.30, 0.45 lb N tree⁻¹ yr⁻¹) and three fertigation frequencies (3x/year, monthly, weekly). An untreated control was included. Trunk diameter was not responsive to N rate or fertigation frequency. Leaf N in all treatments, even controls, remained above the critical level (2.5%). However, at each N rate leaf N was highest with the weekly fertigation frequency. Nitrate analyses of soil samples indicate that nitrate leaching was highest with the highest N rate and 3x/year fertigation. Frequent fertigation is recommended because it results in higher leaf N and less nitrate leaching.

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Thompson, Thomas L., Scott A. White, James Walworth, and Greg Sower. "Development of Best Management Practices for Fertigation of Young Citrus Tree." College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/226095.

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'Newhall' navel oranges on 'Carrizo' rootstock were planted in Mar. 1997 at the Citrus Agricultural Center. The objectives of this experiment were: i) to determine the effects of N rate and fertigation frequency for microsprinkler-irrigated navel oranges on tree N status, and crop yield and quality; and ii) to develop Best Management Practices which promote optimum tree growth and production while minimizing nitrate leaching. The trees are equipped with a microsprinkler irrigation system. The experiment is a randomized complete block factorial with N rates of 0, 0.15, 0.30, and 0.45 lb N/tree/year, and fertigation frequencies of weekly, monthly, and three times per year. Unfertilized control trees are also included in the experimental design. Each of the ten treatments is replicated five times. The trees were harvested for the first time in Feb. 2001. Fruit were processed through an automatic fruit sizer, and fruit from each plot were further evaluated for fruit quality. Although unfertilized control trees had lower leaf N content than fertilized trees, fruit yield and quality of controls was no lower than fertilized trees. Similarly, there were few statistically significant differences in fruit yield and quality between trees receiving different N rates and fertigation frequencies.

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Thompson, Thomas L., Scott A. White, James Walworth, and Greg Sower. "Development of Best Management Practices for Fertigation of Young Citrus Trees, 2003 Report." College of Agriculture, University of Arizona (Tucson, AZ), 2003. http://hdl.handle.net/10150/198113.

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‘Newhall’ navel oranges on ‘Carrizo’ rootstock were planted in Mar. 1997 at the Citrus Agricultural Center. The objectives of this experiment, conducted during 2000 - 2003, were to i) determine the effects of N rate and fertigation frequency for microsprinkler-irrigated navel oranges on tree N status, and crop yield and quality; and ii) develop Best Management Practices which promote optimum tree growth and production while minimizing nitrate leaching. The trees were equipped with a microsprinkler irrigation system. The experiment was a randomized complete block factorial with N rates of 0, 0.15, 0.30, and 0.45 lb N/tree/year, and fertigation frequencies of weekly, monthly, and three times per year. Each of the ten treatments was replicated five times. The trees were harvested in December or January of each growing season. Fruit were processed through an automatic fruit sizer, and fruit from each plot were further evaluated for fruit quality. Leaf N concentration and fruit yield of 4-6 year old trees were responsive to N rate, but not to fertigation frequency. Fruit quality and packout were not significantly affected by either N rate or fertigation frequency. Fruit yield was optimized at annual N rates of 0.25 lb/tree (four-year-old trees) to 0.35 lb/tree (six-year-old trees) during this experiment. We propose new tissue guidelines for guiding N fertilization of young microsprinkler-irrigated navel oranges.

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Thompson, Thomas L., Scott A. White, James Walworth, and Greg Sower. "Development of Best Management Practices for Fertigation of Young Citrus Trees, 2002 Report." College of Agriculture, University of Arizona (Tucson, AZ), 2002. http://hdl.handle.net/10150/223671.

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'Newhall' navel oranges on 'Carrizo' rootstock were planted in Mar. 1997 at the Citrus Agricultural Center. The objectives of this experiment were to i) determine the effects of N rate and fertigation frequency for microsprinkler-irrigated navel oranges on tree N status, and crop yield and quality; and ii) develop Best Management Practices which promote optimum tree growth and production while minimizing nitrate leaching. The trees are equipped with a microsprinkler irrigation system. The experiment is a randomized complete block factorial with N rates of 0, 0.15, 0.30, and 0.45 lb N/tree/year, and fertigation frequencies of weekly, monthly, and three times per year. Unfertilized control trees are also included in the experimental design. Each of the ten treatments is replicated five times. The trees were harvested in Jan. 2002. Fruit were processed through an automatic fruit sizer, and fruit from each plot were further evaluated for fruit quality. Leaf N concentration was responsive to N rate, but not to fertigation frequency. Leaf N in all fertilized plots was above tissue critical levels. Fruit yield in fertilized plots was higher than in unfertilized plots, but, in fertilized treatments, there was no significant effect of N rate or fertigation frequency on fruit yield or quality.

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Falato, Antonio di Bruno. "Water footprint of Ischia Island: preliminary evaluation." Master's thesis, ISA-UL, 2014. http://hdl.handle.net/10400.5/13012.

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Mestrado Vinifera Euromaster - Instituto Superior de Agronomia - UL
We are witnessing in recent years to a climate change due to a number of operations carried out by man. In this sense, agriculture is a strategic sector if we want to tackle this situation, more and more unsustainable as modern agriculture, also called "intensive", is causing more of a problem is the surface layer of the earth's crust, that the biosphere. The following work is part of a larger project, called VA.RIVI, applied on the island of Ischia, and is designed to specifically consider the components that form the basis for the calculation of the Water Footprint, which indicates the environmental impact of a product, a process or an entire company working on water resources. The WF is a relatively new tool, whose standard (ISO14046) was published not more than three months ago, on November 2014, so this does not always work considers the water footprint, but often refers to other indicators of the environmental impact, such as the Carbon Footprint, Ecological Footprint, or the Life Cycle Assessment. Will be analyzed the guidelines of the new ISO 14046, also reporting a sample calculation made possible thanks to the publications present in the bibliography, and will be compared to the production of organic wine. The work is complemented by a number of best practices to reduce the water footprint, but also to reduce the environmental impact of a company or a business process through small and large measures to be implemented at all levels.
N/A

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Lowery, James B. "Factors influencing best management practice implementation in Virginia's Chesapeake Bay drainage basin." Master's thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-01202010-020325/.

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Goeschel, Tyler. "Quantifying Soil Greenhouse Gas Emissions And Soil Carbon Storage To Determine Best Management Practices In Agroecosystems." ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/644.

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Intensive agriculture, coupled with an increase in nitrogen fertilizer use, has contributed significantly to the elevation of atmospheric greenhouse gases (GHGs), including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Rising GHG emissions usually mean a decrease in soil carbon. Currently, soil C is twice that of all standing crop biomass, making it an extremely important player in the C cycle. Fortunately, agricultural management practices have the potential to reduce agricultural GHG emissions whilst increasing soil C. Management practices that impact GHG emissions and soil C include various tillage practices, different N fertilization amounts and treatments (synthetic N, cattle manure, or a combination of both), the use of cover crops, aeration, and water levels. Employing agricultural best management practices (BMPs) can assist in the mitigation and sequestration of CO2, N2O and soil C. Measuring soil carbon storage and GHG emissions and using them as metrics to evaluate BMPs are vital in understanding agriculture's role in climate change. The objective of this research was to quantify soil carbon and CO2 and N2O emissions in agroecosystems (dairy, crop, and meat producing farms) under differing management practices. Three farms were selected for intensive GHG emissions sampling: Shelburne Farm in Shelburne, VT, a dairy in North Williston, VT, and Borderview Farm in Alburgh, VT. At each site, I collected data on GHG (CO2 and N2O) emissions and soil carbon and nitrogen storage to a depth of 1 meter. Soil emissions of CO2 and N2O were taken once every two weeks (on average) from June 2015 through November, 2015 using static flux chambers and a model 1412 Infrared Photoacoustic Spectroscopy (PAS) gas analyzer (Innova Air Tech Instruments, Ballerup, Denmark). Fluxes were measured on 17 dates at Shelburne Farms, 13 dates at the Williston site, and 13 dates in the MINT trial. Gas samples were taken at fixed intervals over a 10-14 minute time frame, with samples normally taken every one or two minutes. I also measured soil carbon to a depth of 1m in six BMPs at Borderview Farm. Overall, I found that manure injection increased N2O and CO2 emissions, but decreased soil C storage at depth. Tillage had little to no impact on N2O emissions, except at Shelburne Farms, where aeration tillage decreased N2O emissions (marginally significant, P < 0.1). No-till did, however, decrease CO2 emissions relative to other conservation tillage practices (strip and vertical tillage) but we were unable to detect a significant change in soil C due to tillage practices. At Borderview farm, N2O emissions increased with soil NO3 and soil moisture, while CO2 emissions increased with soil temperature and nitrate. At Williston, CO2 emissions only increased with temperature; at Shelburne CO2 emissions increased with nitrate. N2O fluxes at Shelburne and Williston were not associated with any of the measured covariates.

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Kopec, David M., Jeff J. Gilbert, James Walworth, Mohammed Pessarakli, D. Kerr, and J. Spence. "Best Management Practices for Sea Isle 2000 Surface Conditions as a Putting Green Turf Under Desert Conditions." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2004. http://hdl.handle.net/10150/216566.

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Sea Isle 2000, the recently developed Seashore paspalum cultivar intended for use on golf greens, was subjected to various surface cultivation practices of grooming, vertical mowing, and topdressing frequency, in order to investigate the (1) effects of these cultural practices on turfgrass quality (2) effects on ball roll distance (BRD), so as to devise best management practices (BMP) for cultural management recommendations for this grass in a hot/dry climate. The trial was conducted for the two summer seasons of 2002 (year1), and 2003 (year 2). Turfgrass quality in year 1 was significantly affected by imposed management treatments on all four evaluation dates, in which the groom vs. non-groom contrast was highly significant. Nongroomed treatments produced better quality than turf groomed 5-6x weekly. In year two, the cultural management treatment effect was not significant, and treatment means ranged from 5.5 to 7.8. The nongroomed/ topdressed and verticut at 14-day treatment had mean quality scores of 7.0 or greater on three of four evaluations in year two. This treatment had the least number of cultural management contact events. The most aggressive treatment in terms of the number of contact events (groom/topdressed and vertically mowed at 7 days) never reached a mean quality score of 7.0, but had acceptable turf otherwise (6.8, 6.5, 5.8 and 6.5 in year two). The treatments that did not receive any vertical mowing (groom/topdressed and verticut at 7 days and groomed/topdressed and verticut at 14 days) always produced mean turf quality scores of 6.0 or above. Over the two year test, the nongroomed treatments which were both verticut and topdressed at 7 or 14 day intervals had 12 of 16 possible quality mean scores of 7.0 or more. The turfs which were groomed and topdressed only at 7 or 14 day intervals (never verticut) had mean quality scores of 7.0 or more on 6 of 16 possible rating scores. Turfs that were groomed/topdressed and verticut at either 7 or 14`day intervals had mean quality scores of 7.0 or greater on 4 of 16 possible evaluation scores. For Ball roll distance (BRD) in year one, the treatment F ratio was significant on five of the ten BRD measurement events, with significance occurring on double mowed turfs on three events, and twice when plots received supplemental rolling. Rolling with an 875 lb Brouer roller numerically increased BRD values on all treatments (over double mowing alone) on 5 July, 16 August, and 26 August, decreased BRD values on 19 July, and had no effect for BRD on 26 July. The greatest BRD values which occurred during year one, was a test mean of 103 inches (double mow only) and 98" for rolled turfs. In year two, the treatment F ratio for treatment effects was not statistically significant on any evaluation date. This was true when BRD was taken after turfs were double mowed, and also followed by rolling. Rolling had minimal benefit, and was inconsistent in BRD effect. BRD was almost 20% greater in year two than a in year one. When BRD was recorded only after double mowing, turfs that were not groomed ranked numerically higher than groomed turfs for BRD response on all data sampling dates in year one. In general, turfs which received the most frequent number of cultural management practices (regular grooming, topdressing and vertical mowing ) tended to have the lowest ranking BRD values, except towards the seasons end (16 and 26 August). Although the main "treatment" effect in the ANOVA was significant on 3 of 5 collection dates (for double mowed BRD values), these trends show that in general, regular grooming decreased BRD values more so than for non-groomed surfaces. In year two, BRD values were essentially identical in mean performance, ranging only a few inches in BRD when measured after the standard double mowing. The greatest difference in BRD among treatments occurred on 27 June, as a BRD of 99.8" occurred for turfs that were non-groomed/topdressed and vertically mowed every 7 days versus non-groomed/topdressed and vertically mowed every 14 days (105"). Again note that there were no significant treatment effects for BRD in year two. When BRD was measured after mowing, followed by additional rolling , the rolling effect tended to increase BRD values across all treatments in year one, except in July, which normally had the most humid weather. Rolling did increase BRD values by 10% in early July (July 5), but also decreased, or had no effect on BRD in the middle or late July (16 and 26 July), and then increased BRD values slightly in August (16, 26 August) of year one. Although the largest increase in BRD values from rolling occurred in early July (almost 9 inches) of year one, the effect was not significant between surface treatments. Rolling was significant when imparted across surface management treatments in August of year 1, as at least one of the two non-groomed turfs tended to have the largest BRD values after rolling. In year two, supplemental rolling imparted very little gain in BRD, except in late September. Substantial increases or decreases in BRD did not occur from rolling relative to treatments in year two, as sometimes occurred in year one. BRD averages across all treatments (with the addition of rolling) were from 96.4" - 109.8" in year two. For both years, rolling) was inconsistent with respect to BRD. Rolling on the day of BRD assessment only sometimes increased, decreased, or had no effect on BRD. Rolling as a regular cultural management treatment should be evaluated. BMPS for Quality and BRD Performance together: In year one, the "groom" treatment which was verticut and topdressed every 7 days always ranked the slowest for BRD responses. While this specific treatment always ranked lowest in BRD, it did not have the lowest overall turf quality scores. Groomed turfs which were verticut and topdressed every 14 days ranked the lowest for quality scores on three of four evaluation dates. Therefore in year one, treatments which produced (in general terms) the greatest BRD values and ranked the highest in overall quality were turfs which received no-grooming, and topdressed either every 14 or 7 days. The treatment which produced the lowest ranking BRD values and lowest ranking quality scores in year one, was the treatment of grooming, verticutting and topdressing every 14 days. In year two, BRD was not related to any surface cultivation treatment. Although not statistically significant, nongroomed plots topdressed either at 7 or 14 day intervals, ranked first for BRD in late season (3 September, 30 September). BRD values were in general, 10-20% greater across all treatments in 2003 than in 2002. Although BRD and quality were not significant in year two, certain trends resulted over the two year test period in that plots that were not groomed had mean treatment quality scores of 7.0 or more on 12 of 16 possible (joint treatment) evaluations. These treatments also had high BRD values. Also, treatments devoid of vertical mowing (groomed/topdressed only at either 7 or 14 day intervals) produced mean quality scores of 7.0 or more on 6 of 16 possible (joint treatment) events over the two year period. BRD values for these treatments were always within 1-2 inches of the test mean BRD values as well. Treatments which received the most frequent contact events (regular grooming/topdress/verticut at either 7 or 14 day intervals over two years, had mean quality scores of 7.0 or greater on only 16 possible events. Over the course of the study, in general, turfs which were non-groomed / verticut and topdressed @ either 7 or 14 day intervals produced the higher ranking quality turfs, along with higher ranking BRD performance. Long term BRD values would most likely include a mixture of topdressing and verticutting either at 7 or 14 days internals, with grooming practiced on an as needed basis, especially during the first two thirds of the summer season.

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McFarland, Kelly. "Twenty-First Century Local Food Farmers in North Texas: An Evaluation of Farming Methods, Best Practices, and Common Struggles." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1609143/.

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Research with local farmers and local food consumers in the North Texas area which captures a contemporary understanding of the challenges and successes present in North Texas local farm-and-food networks. Through ethnographic research methods, including participant-observation and semi-structured interviews, the network of producers and consumers around several farmers' markets were evaluated to understand where the strengths of local food lie, and where networks need development to promote a more stable local food environment. Texas is newer to the trend of farmers' market development, with the local food system developed to foster community, educate, and promote the advantages of locally sourced goods. This research led to the academic discovery of climate adaptive ecological knowledge and farm commodification strategies; which are tools that farmers may use to build greater defense against threats to a farm's livelihood.

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Smith, Clifton Lee Jr. "Assessing Landowner Level Costs for Riparian Forest Buffer System Adoption on Farms in Virginia's Chesapeake Bay Watershed." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36906.

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Riparian Forest Buffer Systems contribute to non-point source pollution control and improve the physical and trophic qualities of streams. There is a limited understanding of the full range of costs incurred when implementing a RFBS. Establishment costs will vary with the site characteristics. The amount of forgone income will vary with the current land-use. RFBS enterprises may yield returns that partially or fully offset forgone income. Section A discusses the physical characteristics and functions of RFBS in the Chesapeake Bay Watershed. Section A argues that RFBS design and site characteristics alter the physical ability of RFBS to produce environmental services. Altering design specifications may come at little environmental loss but might greatly reduce landowner costs. Section B describes a decision support system that can provide landowners and policy makers with financial information on the site specific changes in costs that occur as RFBS designs are altered. Section C utilizes the decision support system software to simulate the common design and site characteristics found within the Chesapeake Bay Watershed of Virginia. Generalizations are drawn concerning reduction efficiencies of a RFBS based on the physical characteristics of the regions. Section D discusses government policies and incentive programs, as well as additional private income opportunities, that may influence the cost and adoption of RFBS. Findings revealed a range of annual per acre cost of adoption between $140.09 rising to a positive return of $124.79, depending on assumptions of site characteristics, land-use, and supplemental financial incentives.
Master of Science

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40

Johnson, Reed M. "On-Farm Assessment of Soil Properties under Different Management Practices in West-Central Ohio." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461092609.

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41

Widner, David E. "Old Order Amish Beliefs About Environmental Protection and the Use of Best Management Practices in the Sugar Creek Watershed." Kent State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=kent1290405236.

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42

Soder, Jeff R. "4-H State Leaders’ Readiness to Support Lesbian and Gay Youth-Assessing Leaders’ Lesbian and Gay Knowledge, Homophobic Attitudes, and Best Practice Implementation." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1259598794.

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Athreya, Brinda K. "Spatially Assessing the perceptions and motivations of farmers implementing Best Management Practices (BMPs) in the Western Lake Erie Basin." University of Toledo / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1588932667586433.

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44

Sekaluvu, Lawrence. "Assessment of ephemeral gully erosion using topographic and hydrologically based models in Central Kansas." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/20557.

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Master of Science
Department of Biological and Agricultural Engineering
Aleksey Sheshukov
The global requirements for food and agricultural products have increased enormously in recent years mainly due to increase in global population. More land is brought under human development and cultivation including marginal lands that are susceptible to degradation processes of erosion, waterlogging, and depletion of organic matter. The resulting effects include; deprivation of the roles performed by the environment, high costs of water treatment, and sedimentation of water reservoirs. This study aims at assessment of ephemeral gully (EG) erosion using topographic and hydrologically based models in two paired watersheds in Central Kansas. The effects of best management practices (BMPs) implementation on EG formation, and erosion rates within the watershed are discussed. The topographic index (TI) models used include: slope area model (SA), compound topographic index model (CTI), wetness topographic index model (WTI), slope area power (SA2), kinematic wave model (nLS), and modified kinematic wave model (nLSCSS). EGs predicted by each model threshold were compared with observed EGs obtained through digitization and field reconnaissance. The agreement of thresholds obtained from location and length approaches were compared by means of drainage density concept. Statistical analysis was performed by error matrix for EG location analysis, and root mean square error (RMSE) and Nash–Sutcliffe efficiency (NSE) for EG length analysis. A TIN-based real-time integrated basin simulator (tRIBS) model, a physically-based, distributed hydrological model was coupled with an EG erosion component (Foster and Lane model) to estimate the erosion rates, and effect of installation of BMPs on reduction of EG erosion rates from agricultural fields. The results indicated that TI models could predict EG location with a maximum total accuracy of 70%. The effectiveness of TI models at prediction of EGs is affected by watershed features such as installed structural best management practices, roads, and culverts. The CTI model outperformed all the TI models at prediction of EGs with maximum Kappa and NSE values of 0.32 and 0.55 respectively, and a minimum RMSE value of 0.087 m. Structural BMPs are effective at controlling erosion from croplands, however, the effectiveness of structural BMPs at reduction of sediment loadings from EGs vary depending on surface cover, and BMP geometry.

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Gouriveau, Fabrice. "Constructed farm wetlands (CFWs) designed for remediation of farmyard runoff : an evaluation of their water treatment efficiency, ecological value, costs and benefits." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/3806.

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Farmyard runoff, i.e. the effluent generated by the rain falling over farmyards, tracks and roofs, is a significant and overlooked source of nutrients and pathogens which degrades aquatic ecosystems through eutrophication, siltation and wildlife poisoning, raises public health concerns, and incurs considerable costs for society. Among other Best Management Practices implemented to address agricultural water pollution and help achieve compliance with the Water Framework Directive, Constructed Farm Wetlands (CFWs), i.e. shallow surface flow wetlands comprising several vegetated cells in series, are being recommended for remediation of farmyard runoff, due to their capacity to remove or store pollutants. Investigation is therefore needed of their long-term water treatment efficiency and ecological value to optimize their design and cost-effectiveness and minimize their negative externalities. The main aims of this study were to: 1) evaluate the treatment performance of CFWs and the link between design, hydrology and efficiency; 2) assess their ecological value and the influence of water quality and design on wetland ecology; 3) identify their costs, benefits and the way they are perceived by farmers; and 4) inform guidelines for the design, construction and aftercare of sustainable CFWs. Research focused on two CFWs in south-east Scotland, one at a dairy farm and one at a mixed beef-arable farm, which receive runoff from yards and roofs, field drainage and septic tank overflow. From February 2006 to June 2008, rainfall, evaporation, water levels and flow at the CFWs were monitored, and their treatment efficiency was assessed from water samples collected manually regularly or with automatic samplers during storm events, and analysed using standard methods. In addition, their ecological value was assessed twice a year from vegetation and aquatic macroinvertebrate surveys. Finally, semi-structured interviews with eight farmers and a farm advisor and discussions with three CFW designers in Scotland and Ireland allowed collection of technical and economic data on farm practices, CFW construction and maintenance, and helped assess CFW cost-effectiveness and acceptance by farmers. Both CFWs reduced pollutant concentrations between inlet and outlet, with efficiencies at CFW1 and CFW2 respectively of 87% and < 0% for five-day biochemical oxygen demand, 86% and 83% for suspended solids, 68% and 26% for nitrate/nitrite, 42% and 34% for ammonium, and 12% and 31% for reactive phosphorus. Nevertheless, the concentration of all pollutants at the outlet of CFW1, and concentration of nitrate/nitrite at the outlet of CFW2 frequently exceeded river water quality standards. Water treatment efficiency varied seasonally, being significantly lower in winter, mainly due to lower temperatures, increased volume of inputs and reduced residence time. The ecological value of the two CFWs differed greatly. At CFW1 and CFW2 respectively, 14 and 22 wetland plant species and 24 and 46 aquatic macroinvertebrate species (belonging to 13 and 27 BMWP scoring families respectively) were recorded, illustrating the greater biodiversity conservation value of CFW2, which was one year older, larger, cleaner, comprised several ponds with a combination of open water and densely vegetated areas, and was subsequently more structurally diverse. The socio-economic study revealed that, despite significant costs associated with their construction (£20 000-£50 000 ha-1) and maintenance (£900-£1500 ha-1 yr-1), CFWs may still represent a more cost-effective alternative than conventional methods. However, their adoption, implementation and sustainable use by farmers were conditioned by land availability and suitability, existing farm infrastructure, detailed information on limitations and maintenance requirements, and adequate financial support for both construction and aftercare. To ensure a long-term, consistent and efficient water treatment, and to enhance biodiversity and landscape, well-maintained, large, vegetated, multi-cell CFWs with shallow overflows are recommended. Their size should be adapted to local precipitation patterns and catchment characteristics. Keywords: agriculture, best management practice (BMP), biodiversity, constructed farm wetland (CFW), costs, farmyard runoff, water pollution, water treatment.

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Smith, Craig Matthew. "An analysis of alternative soil, nutrient, and water management strategies." Diss., Kansas State University, 2011. http://hdl.handle.net/2097/10723.

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Doctor of Philosophy
Department of Agricultural Economics
Jeffery R. Williams
The two topics addressed in this dissertation are both related to surface water quality. Reservoir sedimentation and water quality trading are examined from economic and environmental perspectives. Each topic and the resulting policy implications are relevant to stakeholders at the local, state, and federal levels. Reservoir sedimentation has been recognized as a major environmental, social, and economic issue in much of the Midwestern US. There is an effort to focus public and private funds to achieve the greatest return on the investment from soil erosion and sediment reduction strategies. How can physiographical and economic relationships within the watershed be quantified in such a way to provide insights into the selection of alternative management strategies? This study focuses on answering that question by integrating a physically-based watershed model with an economic analysis of alternative sedimentation reduction strategies for the case of Tuttle Creek Lake located in northeastern Kansas. Several key finding of this study are that both physiographical and economic factors must be considered for cost-effective conservation to occur. Considering these factors and targeting BMP implementation from 8 to 23 times more cost-effective than random implementation. If targeting cannot be done effectively or if “intangible” costs of BMP implementation are too large, dredging is likely to be more cost-effective. While this research compares the cost-effectiveness of various BMP implementation approaches in Kansas with dredging, the benefits associated with each of these strategies is not addressed. While there is substantial evidence that nonpoint sources have lower nutrient reduction costs than point sources, experience with water quality trading (WQT) reveals a common theme: little or no trading activity. These outcomes suggest the presence of obstacles to trading that were not recognized in the design of existing programs. To examine the ways that various market imperfections may impact the performance of a WQT market, an agent-based model is constructed, which simulates a hypothetical point-nonpoint market. This study first presents an overview of the concepts and simulation modeling technique used and then analyzes the effects of two prominent market impediments identified in the WQT literature: information levels and trading ratios. The results imply that if market designers feel that only a limited number of trades will be consummated, creating an institution that provides accessible information about buyers’ prices is preferred to providing information about sellers’ prices. Overall, more information is always better, but it becomes less important with higher trading ratios.

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Knight, Sharon L. "Best institutional practices for farmworker and community equity-sharing schemes in South Africa." Thesis, 2003. http://hdl.handle.net/10413/5500.

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Farmworker equity-share schemes were initiated by the private sector in the Western Cape region of South Africa in the early 1990's as a method of redistributing farm assets to land reform beneficiaries while maintaining the viability of commercial farming operations. This study set out to identify the institutional characteristics of successful farmworker equity-share schemes in South Africa, and to discern a set of best institutional practices that will likely promote the success of future equity-share schemes. A detailed study of nine commercial farming ventures involving partnerships with farmworkers was undertaken in the Western Cape during November 2001 to explore relationships between their institutional arrangements, worker empowerment, management quality and performance. Farmworker equity-share schemes (FWES) have received both positive and negative publicity. This thesis adds to the debate surrounding these land reform projects by comparing the results of case studies conducted by the Surplus People's Project in 1998 with more recent (2001) case studies. The latter suggest that many of the concerns raised by the Surplus People's Project, such as beneficiaries' participation and expectations, power relations between management and worker-shareholders, skills transfer and labour relations, have been addressed. The dissertation also highlights those issues that remain areas of concern, for example, beneficiaries' tenure security, literacy levels amongst worker shareholders, skill and wage differences between men and women, and exit procedures. A cluster analysis of variables measuring four constructs of a successful farmworker equity-share scheme, viz. sound institutional arrangements, effective worker empowerment, competent management and good performance, revealed positive relationships between these constructs. Best institutional practices identified by the analysis suggest that farmworker equity-share schemes should be operated as (or like) a company with voting and benefit rights proportional to individual shareholdings, but with restrictions on certain share transactions to prevent free-riding by non-workers and the loss of creditworthiness through sudden outflows of equity and managerial expertise. However, this positive relationship between best institutional practices and enterprise performance is dependent on effective worker empowerment (e.g. skills transfer and gender representation), good governance (e.g. external auditing) and competent management (e.g. schemes to reward worker performance and to resolve disputes). From a policy perspective it is recommended that public land reform grants should be awarded only to beneficiaries of FWES that have been co-financed by a bank or reputable investor as this ensures a thorough financial assessment of the project, and only to projects that can demonstrate a history of good labour relations. It is also recommended that the Department of Land Affairs should consider extending its grants to regular but seasonal farmworkers who wish to participate in an established project. While farmworker equity-share schemes may not provide all of the answers to land reform they have an important role to play in redistributing wealth and de-racialising commercial agriculture in South Africa.
Thesis (M.Agric.Mgt.)-University of Natal, Pietermaritzburg, 2003.

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Stang, Conrad. "AGRICULTURAL BEST MANAGEMENT PRACTICES AND THEIR EFFECTS ON SEDIMENT TRANSPORT CURVES FOR IMPROVED WATERSHED HEALTH." Thesis, 2011. http://hdl.handle.net/10214/3287.

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Eutrophic conditions caused Severn Sound to be listed as an Area of Concern in the 1980’s, it was then delisted in 2002 after implementing a number of agricultural Best Management Practices (BMPs). The focus of this research is to evaluate BMP effectiveness on a watershed scale using both monitoring and modelling. The monitoring data clearly shows that the BMPs significantly reduced the sediment loadings. It also showed that BMPs affect only the intercept and not the slope of the sediment rating curves meaning that BMPs reduce sediment loadings in a linear fashion and at a constant percentage for all sizes of storms. The literature review and associated BMP reduction factors used to model the applied BMPs clearly show that observed and predicted reductions in sediment were experienced and that the model is validated for use on a watershed scale for BMP implementation. The results from this research will further the understanding of how sediment transport curves are affected by Best Management Practices.
Chapter 1 defines the problem and scope of the research study to be examined in this thesis. The literature review presents the current state of knowledge related to the effectiveness of BMPs, sampling techniques, and the use of sediment transport curves, and watershed modelling as a tool to evaluate the use of BMPs. Chapter 3 explains the goals and objectives as well as the study area for this research. Outlined in Chapter 4 are the standard methods used for water quality monitoring and setting-up and calibrating a watershed model. Research results are presented in Chapter 5 and include measured streamflow and water quality results for the respective rivers along with results from watershed modelling. The results section also reflects on the implications for BMP effectiveness and areas of future research. Chapter 6 concludes with a summary of the new information gained from this research and the success of Severn Sound in leading the way in improved use of BMPs for a healthier watershed.
Severn Sound Environmental Association, Greenland International Consulting Ltd., University of Guelph School of Engineering

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Carreira, Rita Isabel Rodrigues. "Economic study of alternative best management practices for swine effluent application to corn in semiarid climate." 2004. http://digital.library.okstate.edu/etd/umi-okstate-1141.pdf.

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Godwin, Derek C. "Implementing best management practices in small commercial and non-commercial animal enterprises." Thesis, 1994. http://hdl.handle.net/1957/35644.

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Abstract:

Small commercial and non-commercial animal enterprises (SCAEs) raise a few beef cows, horses, pigs, sheep, poultry, and other animals on a few acres. These enterprises are often located in suburban areas of watersheds and show potential for degrading water quality through to increased bacterial, nitrogen, and phosphorus concentrations. SCAEs implement Best Management Practices (BNIPs) on a voluntary basis to control their water quality impacts. Off-stream watering areas, with animal access to streams, and covered manure storages are two BMPs which were analyzed in this thesis for effectiveness in reducing bacteria, nitrogen, and phosphorus from entering surface and groundwater in four SCAEs. The four cooperating SCAEs were located in the Tualatin River Basin, and the potential water quality improvements from implementing these two practices in all SCAEs in the basin were discussed. The BMP analyses use results from several studies. Two of these studies analyzed off-stream watering areas for reducing time animals spend watering at the stream. This time was measured and used to estimate the manure defecated in the stream. Reducing time animals spend at the stream decreases direct defecations in the stream and reduces water quality impacts of SCAEs. A third study analyzed a pasture pump as a possible off-stream watering device. It was analyzed for its ability to provide water to 27 Holstein dairy heifers without limiting water consumption. Daily water consumption from the pasture pump was not significantly different than daily consumption from an open water trough. A fourth study predicted the rainfall required to produce runoff from pastured areas in the Dairy-McKay Hydrological Unit Area within the Tualatin River Basin. These required rainfall amounts and runoff frequency were predicted for summer and winter soil conditions. The BMPs were analyzed for a variety of wet and dry conditions during the summer and winter. Off-stream watering areas were most effective in reducing water quality impacts of SCAEs for dry conditions during the summer and winter, while the covered manure storages were most effective during winter days of continuous rain. Off-stream watering areas reduced the time animals spent at the stream by 75%. Consequently, defecations at the stream were assumed to be reduced 75% and the SCAEs'water quality impacts decreased. Covered manure storages protect manure piles from rain and surface water runoff and prevent bacteria and nutrients from entering the stream or leaching to groundwater regardless of the weather. However, the amount prevented varies with weather conditions. An uncovered manure pile was estimated to cause no water quality impacts during dry weather. During wet weather, the bacteria and nutrients reaching the stream from an uncovered manure pile was estimated to be 60% of the quantity released. The maximum amount of nitrogen leaching to groundwater was estimated to be 10% of the amount applied to the pile since the previous rain. In addition to implementation costs of BMPs, there are changes in annual revenue and costs associated with the management changes. Partial budget analyses were conducted for the four SCAEs to determine their changes in annual monetary returns to management. Both BMPs resulted in negative changes in annual returns to management for all four enterprises.
Graduation date: 1994

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Dissertations / Theses on the topic 'Agricultural best practices'

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