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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Continuous watershed-scale hydrologic modeling of conservation practices for peak flow reduction

Krasowski, Michael 01 May 2019 (has links)
Iowa first started seeing largescale changes to its landscape with the arrival of Europeans and ensuing conversion of forest and prairie to row crops and pasture and would see its landscape altered again in the early 1900s through the conversion of wetlands to row crops. Watersheds in Iowa, and the Midwest at large, have been drastically altered hydrologically—through land use change, tile drainage, digging of drainage ditches, and channelizing of meandering streams. Though drainage practices maximize arable land, they also induce higher flood peaks. Along with these practices, climate change also has the potential to increase flood peaks. Conservation practices —typically employed to reduce erosion and agricultural pollution—have been proposed to be used to reduce flood peaks, but little analysis has been done on their ability to do so at the watershed-scale. To quantify the impact implementing conservation practices at the watershed-scale has on flood peaks, a novel hydrologic model is run to simulate five conservation scenarios under both historic and increased precipitation continuously for seventeen years. The Generic Hydrologic Overland-Subsurface Toolkit (GHOST) is used to model the Boone River, an agriculturally dominated watershed in Iowa. The Boone River model is calibrated against the United States Geological Survey gaging station near the outlet of the watershed and achieves notable success. For the seventeen year study period from 2002 to 2018, calibration achieved a Nash Sutcliffe efficiency of 0.79, percent bias of -6.0 percent, and R2 of 0.80. To simulate the change from the baseline to a conservation practice, changes were made to the parameters of the baseline, calibrated model to reflect the effects of conservation practices. Scenarios run were the return of row crop acres to native vegetation, improved soil health via cover crops and no-till farming, distributed wetlands, conversion of river-adjacent row crop elements to native vegetation, and conversion of stream order one river-adjacent row crop elements to native vegetation. Results for the seventeen year study period show the average peak flow reductions simulated for the conservation scenarios are 82, 39, 9, 13, and 9 percent respectively for annual maximums and 75, 29, 10, 11, and 7.5 percent respectively for the peaks over the 2-year flood threshold. Of the five scenarios modeled, only native vegetation and cover crops were able to offset the increased precipitation anticipated from climate change.
2

Assessing the environmental and educational value of an agricultural watershed restoration project in Mississippi

McCrary, Audrey K 01 May 2020 (has links)
With a majority of land in the United States being utilized for agricultural production, water resource conservation has become a significant topic of interest for natural resource agencies. In partnership with the Mississippi Department of Environmental Quality and Natural Resources Conservation Service, Mississippi State University conducted a stream restoration project within its agricultural research properties in Oktibbeha County, Mississippi. Water sampling during storm-runoff events was conducted to assess changes in microbial, nutrient, and sediment concentrations and loads pre- and post-restoration. In addition to these water monitoring activities, a regional survey of Cooperative Extension Service agents with agriculture and natural resource responsibilities was conducted to assess the need for in-service training on water resource conservation topics. Water quality monitoring and agent survey data were used to evaluate the restoration project’s environmental impact and potential as a demonstration site for future agent training initiatives for water resource conservation.
3

Understanding how crop insurance impacts adoption of conservation practices

Michelle R Hemler (7479974) 17 October 2019 (has links)
In recent years, agricultural magazine articles have positioned crop insurance requirements as a barrier to conservation adoption. Our research uses a mixed-methods design with Midwest conventional corn farmers to identify if crop insurance is a hindrance to adoption. Qualitative data was analyzed in Nvivo using thematic coding and quantitative data was analyzed using Stata statistical software. Our results indicate that crop insurance is not a direct barrier to adoption. Rather, farmers identify distinct and complimentary outcomes for risk-management from participating in both crop insurance and conservation. These findings reflect broader perspectives on Midwest conventional corn producers’ beliefs and rationale for using crop insurance and/or conservation practices.
4

Professional development internship: Canadian Conservation Institute, Ottawa, Canada

Mulford, Therese, n/a January 1983 (has links)
n/a ----Introduction---- I have presented my dissertation in four specific parts as specified on page 2 of the "Guidelines For Internship Requirements of Master of Applied Science in Material Conservation": Part I: Details of the programme of work carried out Part 11: Description of the function and facilities of the Canadian Conservation Institute Part 111: Details of conservation work carried out: Examination and Treatment Reports Part I V : A. Technical Training Sessions and Lectures B. Visits t o Conservation Laboratories C. Visits to Cultural Institutions Each part can be considered a separate unit and, therefore, the bibliography pertaining to each section follows it immediately, contrary to the usual format of being placed as an entire unit at the end of the dissertation. The use of photographic reproduction and official documentation is restricted for ethical, political, legal, security and other reasons (Appendix 11). Therefore, limited photographic documentation is evident in the treatment reports presented. The CC1 Examination and Treatment format did not comply with the size specifications for the dissertation. Therefore, it was not used. However, the following forms have been reduced and presented in Appendices 111, I V and V: Request for Conservation Services, Request for Analytical Services and Time Log on Work for the National Museum of Man. In addition to the examination and treatment reports, I have chosen to include a literature survey of the tannic acid treatment for ferrous metals. The literature survey increased my understanding of the treatment.
5

Essays on the adoption and intensification of conservation agricultural practices under risk

Canales Medina, Dominga Elizabeth January 1900 (has links)
Doctor of Philosophy / Department of Agricultural Economics / Jason S. Bergtold / In recent years, great attention has been placed on conservation systems for agricultural production. Conservation practices offer economic and environmental benefits, yet conventional practices remain the prevailing system in some regions. As conservation efforts are launched by different local and federal agencies, understanding farmers’ motivations when adopting conservation practices is important to ensure the continuation of adoption through the development of programs that are tailored to meet farmers’ preferences and constraints. The purpose of the first essay was to identify the factors affecting farmers’ choice of tillage practice at the crop level. Farmer’s choice of No-till, Strip-till and Conventional tillage was modeled for dryland corn, wheat and soybean production in Kansas. The results show that tillage decisions are crop-specific and that factors such as risk aversion, baling and grazing of crop residue, crop acreage, and farmers’ approach to adopting new technologies are significant factors affecting farmers’ decisions. The second essay focused on the adoption of continuous no-till, conservation crop rotation, cover crops, and variable rate application of inputs and the effect that incentive payments, payment mechanism, and off-farm environmental benefits from conservation have on the decision to adopt. This essay also examined the risk associated with the variability of net returns and its effect on farmers’ willingness to adopt using a non-linear extended expected utility framework, allowing for the estimation of a utility parameter for net returns, farmer’s subjective judgment of probabilities, and farmers’ risk attitudes. Farmers were found to exhibit risk aversion, with an estimated risk premium of approximately 3% of net returns. Results also suggested a preference for federally-run programs and for programs with higher off-farm environmental benefits. The third essay examined the timing of adoption of continuous no-till, cover crops, and variable rate application of inputs. This study found that risk aversion delays the timing of adoption of cover crops and variable rate application of inputs. However, the timing of adoption of continuous no-till was not affected by risk aversion. Findings also indicated that farmers who consider themselves innovators adopt at a faster rate than their counterparts.
6

A causal analysis of conservation practices on corn yield:evidence from the Mississippi Delta and Arkansas Delta

Pinamang, Melody Afrane 07 August 2020 (has links)
Employing the causal inference methods (matching for binary and continuous treatments), I examined the impact of conservation payments on corn yield. I used the propensity score and covariate distance matching and generalized propensity score methods to manage the problem of selection bias since the enrollment of conservation programs (i.e., receiving conservation payments) is not a randomized experiment. Using USDA Economic Research Service – Agricultural Resource Management Survey (ERS-ARMS) field-level data, I assessed whether receiving conservation payments had harm on corn yield in the Mississippi and Arkansas Delta. The findings from the two binary matchings showed that receiving conservation payments didn’t decrease corn yield. The generalized propensity approach revealed that lower conservation payments received held higher corn yield while higher conservation payments led to lower corn yield.
7

Conservation Planning, What Is Used And What Is Needed: A Needs Assessment Survey Of The Natural Resources Conservation Service

Murdock, Jeremy Neal 15 December 2007 (has links)
How important is conservation planning to society today? It impacts the quality of our most precious natural resources: water, air, soil, wildlife, and plant material as well as every aspect of one of the largest industries in the United States: agriculture. In order to gain a better understanding of the conservation planning process, as well as the elements involved in creating an effective conservation plan, a Web-based survey was administered to one of the leaders in the advancement of conservation planning and planning technology, the United States Department of Agriculture’s (USDA’s) Natural Resources Conservation Service (NRCS). The purpose of this study is to identify the trends and needs within the Mississippi NRCS, as well as to identify the characteristics of a potential end user of a conservation planning tool. The purpose of the survey was to identify the agents’ comfort levels with the conservation planning process, conservation practice design and implementation, numerous incentive programs, water quality testing, and most importantly digital technology.
8

Assessing the Effects of Conservation Practices and Fertilizer Application Methods on Nitrogen and Phosphorus Losses from Farm Fields – A Meta Analysis

Nummer, Stephanie Ann January 2016 (has links)
No description available.
9

ASSESSING THE ROLE OF NORMS AND INFORMATION IN SHAPING RESIDENTS' INTENTIONS TO ADOPT WATER QUALITY IMPROVEMENT PRACTICES ACROSS URBAN-TO-RURAL LANDSCAPES

Jennifer A. Domenech (5930615) 17 January 2019 (has links)
<p> </p> Nonpoint source (NPS) pollution refers to pollution entering receiving waterbodies from diffuse sources, and is one of the main causes of water pollution in the United States. Best management practices (BMPs) and low impact development (LID) strategies are water and land management practices geared at reducing the effect of NPS pollution. This research focused on residents in northwestern Indiana and assessed their interest in adopting BMPs and LID strategies across the urban-to-rural gradient. Resident groups of interest include medium/large-scale farmers, small-scale farmers, rural non-farming residents, suburban residents, and urban residents. Specifically, this research explored residents’ awareness of and attitudes towards water quality improvement practices, their likelihood of adopting these practices, and factors that influence their likelihood of adoption. Data was collected through a household survey that was mailed to residents of Porter and LaPorte counties. In addition to survey questions measuring respondents’ awareness, attitudes, perceptions, likelihood of adoption, and demographics, the survey also contained an experimental component in the form of an information page. By using descriptive, bivariate and multivariate statistical procedures to analyze survey data, this research found that respondents generally reported high levels of awareness of and positive attitudes towards BMPs and LID strategies. Despite this, 41% of respondents reported a likelihood of adopting any water quality improvement practices. This research found that resident groups differed in their awareness of water quality improvement practices, as well as their descriptive and subjective norms associated with adopting these practices. Respondents valued improved environmental quality and reduced flash flood risk as benefits of adopting water quality improvement practices, and identified not knowing enough about specific conservation practices and concerns about how to install and maintain the practices as main barriers to adoption. Generally, respondents who were younger, perceived more problems with various potential water pollution sources, were more aware of water quality improvement practices, had more positive attitudes, had a stronger sense of personal responsibility, sought information in the past about water quality problems, or perceived stronger social expectations from peers (i.e., subjective norms) were more likely to be interested in adopting water quality improvement practices in the next year. The role of information was more ambiguous. While information about how to choose, install and maintain specific water quality improvement practices may be useful for residents, the information treatment about the responsibility of each resident group for NPS pollution did not seem to affect respondents’ likelihood of adoption. However, this research did find that respondents reacted differently to the information provided based on their initial self-reported likelihood of adoption prior to receiving any information. Based on these results, this research suggests strategies that may be used by public and private entities to motivate residents’ adoption of water quality improvement practices, including but not limited to: (1) developing education programs that highlight both the broader environmental quality benefits and geography-specific practical benefits of water quality improvement; (2) developing technical assistance programs that help residents identify appropriate conservation practices for their homes and properties and that facilitate installation and maintenance of such practices; (3) developing communication strategies to help residents establish a sense of self-responsibility and align their perceived water quality problems with their own actions; and, (4) developing outreach programs to help establish and facilitate descriptive and subjective norms in favor of adopting water quality improvement practices at the watershed scale. <br> Nonpoint source (NPS) pollution refers to pollution entering receiving waterbodies from diffuse sources, and is one of the main causes of water pollution in the United States. Best management practices (BMPs) and low impact development (LID) strategies are water and land management practices geared at reducing the effect of NPS pollution. This research focused on residents in northwestern Indiana and assessed their interest in adopting BMPs and LID strategies across the urban-to-rural gradient. Resident groups of interest include medium/large-scale farmers, small-scale farmers, rural non-farming residents, suburban residents, and urban residents. Specifically, this research explored residents’ awareness of and attitudes towards water quality improvement practices, their likelihood of adopting these practices, and factors that influence their likelihood of adoption. Data was collected through a household survey that was mailed to residents of Porter and LaPorte counties. In addition to survey questions measuring respondents’ awareness, attitudes, perceptions, likelihood of adoption, and demographics, the survey also contained an experimental component in the form of an information page. By using descriptive, bivariate and multivariate statistical procedures to analyze survey data, this research found that respondents generally reported high levels of awareness of and positive attitudes towards BMPs and LID strategies. Despite this, 41% of respondents reported a likelihood of adopting any water quality improvement practices. This research found that resident groups differed in their awareness of water quality improvement practices, as well as their descriptive and subjective norms associated with adopting these practices. Respondents valued improved environmental quality and reduced flash flood risk as benefits of adopting water quality improvement practices, and identified not knowing enough about specific conservation practices and concerns about how to install and maintain the practices as main barriers to adoption. Generally, respondents who were younger, perceived more problems with various potential water pollution sources, were more aware of water quality improvement practices, had more positive attitudes, had a stronger sense of personal responsibility, sought information in the past about water quality problems, or perceived stronger social expectations from peers (i.e., subjective norms) were more likely to be interested in adopting water quality improvement practices in the next year. The role of information was more ambiguous. While information about how to choose, install and maintain specific water quality improvement practices may be useful for residents, the information treatment about the responsibility of each resident group for NPS pollution did not seem to affect respondents’ likelihood of adoption. However, this research did find that respondents reacted differently to the information provided based on their initial self-reported likelihood of adoption prior to receiving any information. Based on these results, this research suggests strategies that may be used by public and private entities to motivate residents’ adoption of water quality improvement practices, including but not limited to: (1) developing education programs that highlight both the broader environmental quality benefits and geography-specific practical benefits of water quality improvement; (2) developing technical assistance programs that help residents identify appropriate conservation practices for their homes and properties and that facilitate installation and maintenance of such practices; (3) developing communication strategies to help residents establish a sense of self-responsibility and align their perceived water quality problems with their own actions; and, (4) developing outreach programs to help establish and facilitate descriptive and subjective norms in favor of adopting water quality improvement practices at the watershed scale.
10

Identification of potential conservation practices and hydrologic modeling of the upper Iowa watershed

Rundhaug, Trevor Julian 01 August 2018 (has links)
In 2016 the Iowa Watershed Approach (IWA) was created to increase community resiliency against flooding, to develop hydrologic assessments that would identify strategies to reduce flooding, and to implement those strategies within nine identified watersheds that experienced flooding between 2011 and 2013. One of the nine watersheds was the Upper Iowa watershed located in northeast Iowa. This thesis focuses on the work that has been done to create a hydrologic assessment of the Upper Iowa watershed. The hydrologic assessment identifies potential conservation practices, creates a hydrologic model to assess the hydrologic cycle over the past ten years, and identifies strategies to reduce flooding within the watershed. Many potential agricultural conservation practices within the Upper Iowa watershed were identified and trends relating to the soil, land use, and topography were determined. In addition, a methodology to compare potential conservation practices with existing conservation practices actually in place was developed including a tool to estimate the size of grassed waterways to NRCS design guidelines. The comparison validated the methodologies used to identify potential practice placements, identified locations where potential practices could be implemented, and showed how stakeholder preferences influence conservation implementation. Additionally, a hydrologic model of the Upper Iowa watershed was developed, using the new Generic Hydrologic Overland-Subsurface Toolset model and calibrated to simulate the time period of 2007 through 2016. The model was evaluated against water balance ratios and performance statistics calculated from measured data. The model achieved Nash Sutcliffe Efficiency scores for streamflow above 0.7 and percent bias scores between ±12% for the three wettest years of 2008, 2013, and 2016. With the calibrated model, the benefits of continuous cover crop implementation were investigated under current conditions and under increased extreme precipitation intensity expected from climate change over the next half century. The results of this investigation determined that continuous cover crops increased evapotranspiration within the early half of the year creating more storage within the soil. Thus the flood risk from convective storms during the summer was lowered. In addition, the benefits from cover crops in terms of peak flow and volume reductions were cumulative increasing each consecutive year and were proportional to the percentage of cover cropped area. Lastly, a scenario using cover crops in a future extreme precipitation environment resulted in a reduction of peak discharge to current conditions. The results of this thesis will guide both future work within the Upper Iowa watershed and contribute to the knowledge of hydrologic planning and modeling within agricultural watersheds.

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