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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

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.
2

Žemės ūkio naudmenų atkūrimo ir gerinimo darbų pagrindimas / The base of agricultural land restoration and improvement works

Šimonytė, Renata 25 June 2013 (has links)
Magistro baigiamajame darbe išanalizuoti ir įvertinti žemės ūkio naudmenų atkūrimo ir gerinimo pagrindų teoriniai ir praktiniai aspektai, atliktas empirinis melioracijos specialistų bei ūkininkų tyrimas, daromos išvados ir pasiūlymai. Darbas susideda iš dviejų dalių. Pirma darbo dalis – teorinė, šioje dalyje aptariami žemės ūkio naudmenų atkūrimo ir gerinimo darbų teoriniai aspektai: analizuojama jų samprata įstatymuose ir mokslinėje literatūroje, apžvelgiami teisinio reglamentavimo ypatumai. Antroje dalyje pristatoma tyrimo metodologija bei aptariami atlikto empirinio tyrimo rezultatai, kurio metu autorė apklausė Jonavos rajono specialistus-melioratorius bei ūkininkus. / Master's thesis analyzes with the base of agricultural land restoration and improvement works, shows it`s theoretical and practical aspects, also author provide an empirical study of professionals and farmers, make conclusions and recommendations. The work consists of two parts. The first part of the work - theoretical, this section deals with agricultural land restoration and improvement work in theoretical aspects: the analysis of the concept of agricultural land restoration and improvement work as it is written in law and literature, also provides an overview of the legal regulatory features. The second section presents the research methodology and discusses with the results of an empirical study in which the author interviewed Jonava professionals and farmers.
3

<b>EVALUATION OF RISK AND RETURN FOR FARMLAND LEASES</b>

Xiaoyi Lin (18436218) 27 April 2024 (has links)
<p dir="ltr">This study explores the net return and risk associated with different farmland leases, focusing on the tenant’s perspectives. The types of leases investigated include cash rent, crop-share, and eight flex leases. Utilizing data from a case farm in west-central Indiana and employing the @Risk simulation software, the study assesses the financial performance and risk exposure of each lease type. The study's objectives include evaluating net return and risk through simulation models. Hypotheses suggest crop-share leases exhibit lower tenant risk, cash rent leases present higher tenant risk, and flex leases more effectively distribute risk between tenants and landlords. Results indicate that, for risk-averse operators, crop-share leases prove advantageous, while cash rent leases offer higher net returns at the expense of increased risk. Flex leases provide a balanced alternative, mitigating risk while achieving higher net returns than a crop share lease. Stochastic dominance analysis supports the suitability of crop-share and specific flex leases for various risk preferences. Downside risk analysis emphasizes the importance of considering the lower tails of net return distributions. The crop-share lease consistently demonstrates more favorable downside risk characteristics, making it an appealing choice for risk-averse tenants.</p><p dir="ltr">In conclusion, the study contributes valuable insights into the complexities of farmland leasing, offering a nuanced understanding of the trade-offs between net return and risk for different lease types. The results provide practical guidance for tenants seeking leases aligned with their risk preferences and financial goals.</p>
4

<b>IMPACT OF COMMERCIAL AND UTILITY-SCALE SOLAR ENERGY ON FARMLAND PRICE</b>

Binayak Kunwar (18863209) 24 June 2024 (has links)
<p dir="ltr">The expected rapid development of renewable energy in the United States has raised concerns about its effects on farmland prices, yet there is little empirical evidence on the impact of solar energy development on farmland prices. This study aims to examine the heterogenous impact of commercial and utility-scale solar energy on farmland prices in Indi- ana. Drawing on farmland transactions from 2015 to 2020, we employ quantile and expectile hedonic price regressions to estimate the heterogeneous impact of proximity to solar energy facilities across the conditional price distribution. This study finds an inverse, non-linear relation between the proximity to solar energy and per acre land prices. We find that solar farms provide a premium to neighboring farmland parcels. However, this premium is heterogenous, with higher premiums on parcels with higher conditional prices. As we move across the higher conditional expectiles, we observe a price drop ranging from 0.8% (0.1 expectile) to 1.8% (0.9 expectile) for an additional mile increase from neighboring solar farms. Similarly, price premium for a proximity to solar energy is as high as 2.1% for 99th expectile farmland price. Thus, policymakers should consider the effect of solar energy to avoid potential damage on agricultural production and land price movements.</p>
5

Using Digital Agriculture Methodologies to Generate Spatial and Temporal Predictions of N Conservation, Management and Maize Yield

Min Xu (5930423) 03 January 2019 (has links)
<div>The demand for customized farm management prescription is increasing in order to maximize crop yield and minimize environmental risks under a changing climate. One great challenge to modeling crop growth and production is spatial and temporal variability. The goal of this dissertation research is to use publicly available Landsat imagery, ground samples and historical yield data to establish methodologies to spatially quantify cover crop growth and in-season maize yield. First, an investigation was conducted into the feasibility of using satellite remote sensing and spatial interpolation with minimal ground samples to rapidly estimate season-specific cover crop biomass and N uptake in the small watershed of Lake Bloomington in Illinois. Results from this study demonstrated that remote sensing indices could capture the spatial pattern of cover crop growth as affected by various cover crop and cash crop management systems. Soil adjusted vegetation index (SAVI), enhanced vegetation index (EVI) and triangular vegetation index (TVI) were strongly correlated with cover crop biomass and N uptake for low and moderate biomass and N uptake ranges (0-3000 kg ha-1 and 0-100 kg N ha-1). The SAVI estimated cover crop biomass and N uptake were +/- 15% of observed value. Compared to commonly used spatial interpolation methods such as ordinary kriging (OK) and inverse distance weighting (IDW), using the SAVI method showed higher prediction R2 values than that of OK and IDW. An additional advantage for these remote sensing vegetation indices, especially in the context of diverse agronomic management practices, is their much lower labor requirements compared to the high density ground samples needed for a spatial interpolation analysis. </div><div>In the second study, a new approach using the multivariate spatial autoregressive (MSAR) model was developed at 10-m grid resolution to forecast maize yield using historical grain yield data collected at farmers’ fields in Central Indiana, publicly available Landsat imagery, top 30 cm soil organic matter and elevation, while accounting for yield spatial autocorrelation. Relative mean error (RME) and relative mean absolute error (RMAE) were used to quantify the model prediction accuracy at the field level and 10-m grid level, respectively. The MSAR model performed reasonably well (absolute RME < 15%) for field overall yield predictions in 32 out of 35 site-years on the calibration dataset with an average absolute RME of 6.6%. The average RMAE of the MSAR model predictions was 13.1%. It was found that the MSAR model could result in large estimation error under an extreme stressed environment such as the 2012 drought, especially when grain yield under these stressed conditions was not included in the model calibration step. In the validation dataset (n=82), the MSAR model showed good prediction accuracy overall (± 15% of actual yield in 56 site-years) in new fields when extreme stress was not present. The novel approach developed in this study demonstrated its ability to use elevation and soil information to interpret satellite observations accurately in a fine spatial scale. </div><div>Then we incorporated the MSAR approach into a process-based N transformation model to predict field-scale maize yield in Indiana. Our results showed that the linear agreement of predicted yield (using the N Model in the Mapwindow GIS + MMP Tools) to actual yield improved as the spatial aggregation scale became broader. The proposed MSAR model used early vegetative precipitation, top 30 cm soil organic matter and elevation to adjust the N Model yield prediction in 10-m grids. The MSAR adjusted yield predictions resulted in more cases (77%) that fell within 15% of actual yield compared to the N Model alone using the calibration dataset (n=35). However, if the 2012 data was not included in the MSAR parameter training step, the MSAR adjusted yield predictions for 2012 were not improved from the N Model prediction (average RME of 24.1%). When extrapolating the MSAR parameters developed from 7 fields to a dataset containing 82 site-years on 30 different fields in the same region, the improvement from the MSAR adjustment was not significant. The lack of improvement from the MSAR adjustment could be because the relationship used in the MSAR model was location specific. Additionally, the uncertainty of precipitation data could also affect the relationship. </div><div>Through the sequence of these studies, the potential utility of big data routinely collected at farmers’ fields and publicly available satellite imagery has been greatly improved for field-specific management tools and on-farm decision-making. </div>
6

Arbuscular mycorrhizal fungi: crop management systems alter community structure and affect soybean growth and tolerance to water stress

Lisseth Zubieta (5930507) 03 January 2019 (has links)
<p>Arbuscular mycorrhizal fungi (AMF) are best known for their potential to help plants acquire nutrients, especially phosphorous. These microbes improve soil health by promoting soil aggregation and carbon sequestration, and further benefit plants by helping them withstand biotic and abiotic stress. Currently, there are 200 recognized species of AMF within the phylum Glomeromycota. Recent studies indicate that individual AMF species differ in the benefits they provide, with some even acting as parasites. Moreover, AMF community composition can be altered by soil and crop management practices, but the effect of these changes on the benefits conferred by AMF are still not well understood. Consequently, the goal of this study was to determine how two widely used crop management systems can alter the composition of AMF species, and affect the potential for these communities to promote the productivity and drought tolerance. To accomplish this goal, we collected AMF inoculum from a long-term crop systems trial comparing organic and conventional management for use in greenhouse trials where we subjected plants to drought. We collected AMF inoculum during mid-summer when differences between the two management systems were likely cause larger effects on AMF communities, and again in autumn after harvest to see if differences in AMF communities would persist. We determined AMF species composition using next generation sequencing. Results of this study confirm that soil-building practices commonly used in organic farming systems can improve soil health and increase the productivity of food-grade soybeans. They also demonstrate that AMF communities in Indiana croplands are highly diverse, and some of these taxa can improve soybean growth and help plants tolerate water stress. Although the overall diversity of AMF communities did not differ between the organic and conventional management systems in mid-summer, individual AMF taxa did differ between the systems, which were likely responsible for the greater tolerance to water stress observed when plants were amended with inoculum from the organic system. AMF communities present during autumn were significantly different between the two crop management systems, but did not result in differences in drought tolerance of soybeans, indicating that the loss of key AMF taxa in the organic system from the first relative to the second experiment was likely responsible. Finally, plants grown using inoculum from both crop management systems in autumn had greater tolerance to water stress than plants that received a AMF commercial inoculum. This provides further evidence that individual AMF species vary in the benefits they provide, and that the presence of a diverse consortium of AMF species is needed to optimize plant health and productivity in agricultural systems. Agricultural producers should consider incorporating soil-building practices that are commonly used in organic farming systems such as planting winter cover crops, to improve the health of their soil and enhance the productivity of their crops. <b></b></p> <br>
7

Study of the farming community, the Lockyer Valley, Queensland

Oo, Khin Unknown Date (has links)
This study was conducted in two shires of Laidley and Gatton in the Lockyer Valley in 1986. The research method used was a self-administered mail questionnaire sent to four hundred primary producers. The response rate received was 49.5 percent which is quite reasonable for a random sample of a non-specific interest group. The study area was divided into six zones based on the 198 respondents’ assessment of the enterprise from which they derived major income. The main approach of this project was a situational analysis o the Lockyer Valley. Central to this research was identification of the pressure and extent of problems relating to several aspects of land use, notably soil erosion, weed infestation; availability and quality of water and more general community-based problems. The characteristics of farm households, the role of family members in decision-making and tasks related to farm as well as home, were also included in this study. The Lockyer Valley is a major production area of vegetables as well as a mixed farming area. Natural pasture, which was extensively found in Zone 6, was largely used for cattle grazing. Generally, rural women were better educated than their husbands, and the ratio of educational level of husband and wife was higher than previous research findings. A large number of producers and their wives have taken off-farm work, and women tended to spend more time in off-farm employment. Only 6.1 percent of producers’ children had completed tertiary education and the majority of all sons were working on the farm. Partnership was found to be the major type of property ownership and inter-generational transfer of the property was the future plan. The producers who were from a non-farm upbringing and who had already taken up off-farm work intended to leave their properties at some time in the future. With the running of the farm business , 35 percent of rural women worked full-time in partnership with their husbands, and 42 percent worked part-time. However, 23 percent of rural women were homemakers and were not involved in running the farm business. The association between decision-making of husband and wife and situational factors such as ownership, involvement in farm tasks, record-keeping, education, on-farm upbringing and age were analysed. Joint involvement of wives in decision-making was to be related to ownership, farm tasks and record-keeping. However, husbands were more likely to take a major role in decision-making if they were more educated and had an on-farm upbringing. Age was found to be a factor affecting joint decision-making, although this result conflicted with findings of earlier research. The opinions of the farm community in identifying the problems of the specific small area in the Lockyer Valley were revealed. Lantana was the most severe weed problem in the whole catchment. The catchment area also had problems with wattle. The recommended control method of lantana was replacement by improved pasture, but it was adopted by few primary producers. Soil erosion in the form of gullies, bank erosion, sheet erosion, salinity and flooding were some of the problems perceived by the local community. Regular ‘slash and burn’ was practised by most of the producers. This is one of the causes of land degradation. Bore, creek and river, and dam were the main water sources for farm supply and irrigation. Only 60 percent of bored had adequate water supply and good water quality. Farm dam and creek/river sources were less reliable due to the inadequate availability of water. Consequently, operators at about half the cropped farms had to stop growing some vegetables which were previously commercially successful. Within the context of farm family needs, emphasis was placed on conservation of water, because of the erosion and water problems. The community’s opinion on community development activities emphasised the involvement of farm families. Finally, suggestions for the extension program which should be emphasised on rural development by means of community participation were included. The bases for further studies was also provided in this report.
8

Study of the farming community, the Lockyer Valley, Queensland

Oo, Khin Unknown Date (has links)
This study was conducted in two shires of Laidley and Gatton in the Lockyer Valley in 1986. The research method used was a self-administered mail questionnaire sent to four hundred primary producers. The response rate received was 49.5 percent which is quite reasonable for a random sample of a non-specific interest group. The study area was divided into six zones based on the 198 respondents’ assessment of the enterprise from which they derived major income. The main approach of this project was a situational analysis o the Lockyer Valley. Central to this research was identification of the pressure and extent of problems relating to several aspects of land use, notably soil erosion, weed infestation; availability and quality of water and more general community-based problems. The characteristics of farm households, the role of family members in decision-making and tasks related to farm as well as home, were also included in this study. The Lockyer Valley is a major production area of vegetables as well as a mixed farming area. Natural pasture, which was extensively found in Zone 6, was largely used for cattle grazing. Generally, rural women were better educated than their husbands, and the ratio of educational level of husband and wife was higher than previous research findings. A large number of producers and their wives have taken off-farm work, and women tended to spend more time in off-farm employment. Only 6.1 percent of producers’ children had completed tertiary education and the majority of all sons were working on the farm. Partnership was found to be the major type of property ownership and inter-generational transfer of the property was the future plan. The producers who were from a non-farm upbringing and who had already taken up off-farm work intended to leave their properties at some time in the future. With the running of the farm business , 35 percent of rural women worked full-time in partnership with their husbands, and 42 percent worked part-time. However, 23 percent of rural women were homemakers and were not involved in running the farm business. The association between decision-making of husband and wife and situational factors such as ownership, involvement in farm tasks, record-keeping, education, on-farm upbringing and age were analysed. Joint involvement of wives in decision-making was to be related to ownership, farm tasks and record-keeping. However, husbands were more likely to take a major role in decision-making if they were more educated and had an on-farm upbringing. Age was found to be a factor affecting joint decision-making, although this result conflicted with findings of earlier research. The opinions of the farm community in identifying the problems of the specific small area in the Lockyer Valley were revealed. Lantana was the most severe weed problem in the whole catchment. The catchment area also had problems with wattle. The recommended control method of lantana was replacement by improved pasture, but it was adopted by few primary producers. Soil erosion in the form of gullies, bank erosion, sheet erosion, salinity and flooding were some of the problems perceived by the local community. Regular ‘slash and burn’ was practised by most of the producers. This is one of the causes of land degradation. Bore, creek and river, and dam were the main water sources for farm supply and irrigation. Only 60 percent of bored had adequate water supply and good water quality. Farm dam and creek/river sources were less reliable due to the inadequate availability of water. Consequently, operators at about half the cropped farms had to stop growing some vegetables which were previously commercially successful. Within the context of farm family needs, emphasis was placed on conservation of water, because of the erosion and water problems. The community’s opinion on community development activities emphasised the involvement of farm families. Finally, suggestions for the extension program which should be emphasised on rural development by means of community participation were included. The bases for further studies was also provided in this report.
9

Evaluating the Effects of Legacy Phosphorus on Dissolved Reactive Phosphorus Losses in Tile-Drained Systems

Pauline Kageha Welikhe (8803301) 07 May 2020 (has links)
<p>Eutrophication due to phosphorus (P) enrichment continues to be a primary water quality concern affecting freshwater and marine estuaries around the world. Excessive anthropogenic P inputs, driven by the need to meet the rising food and energy demands of a growing and increasingly urbanized population, have resulted in the buildup of P creating legacy (historical) P pools in agricultural landscapes. There is growing evidence that remobilization of accumulated legacy P can interfere with conservation efforts aimed at curbing eutrophication and improving water quality. Less is known about the magnitude and effects of these legacy P pools on dissolved reactive P (DRP) losses in tile-drained systems. This dissertation consists of three separate inquiries into how legacy P may affect DRP losses in tile drains. In the first inquiry, we examined the possibility of developing a suitable pedo-transfer function (pedoTF) for estimating P sorption capacity (PSC). Subsequent PSC-based indices (Phosphorus Saturation Ratio (PSR) and Soil Phosphorus Storage Capacity (SPSC)) were evaluated using daily water quality data from an in-field laboratory. The pedoTF derived from soil aluminum and organic matter accurately predicted PSC (R<sup>2</sup> = 0.60). Segmented-line models fit between PSR and soluble P (SP) concentrations in both desorption assays (R² = 0.69) and drainflows (R² = 0.66) revealed apparent PSR thresholds in close agreement at 0.21 and 0.24, respectively. Linear relationships were observed between negative SPSC values and increasing SP concentrations (R² = 0.52 and R<sup>2</sup> =0.53 respectively), and positive SPSC values were associated with very low SP concentrations in both desorption assays and drainflows. Zero SPSC was suggested as a possible environmental threshold. Thus, PSC-based indices determined using a pedoTF could estimate the potential for SP loss in tile drains. Also, both index thresholds coincided with the critical soil test P level for agronomic P sufficiency (22 mg kg<sup>-1</sup> Mehlich 3 P) suggesting that the agronomic threshold could serve as an environmental P threshold. In the second inquiry, PSC- based indices in addition to other site characteristics present in a P index (PI), were used as inputs in the development of a multi-layer feed-forward artificial neural network (MLF-ANN). The MLF-ANN was trained, tested, and validated to evaluate its performance in predicting SP loss in tile drains. Garson’s algorithm was used to determine the weight of each site characteristic. To assess the performance of ANN-generated weights, empirical data from an in-field laboratory was used to evaluate the performance of an unweighted PI (PI<sub>NO</sub>), a PI weighted using Lemunyon and Gilbert weights (PI<sub>LG</sub>), and an ANN-weighted PI (PI<sub>ANN</sub>) in estimating SP losses in tile effluent. The MLF-ANN provided reliable predictions of SP concentrations in tile effluent (R<sup>2</sup> = 0.99; RMSE = 0.0024). Soil test P, inorganic fertilizer application rate (FPR), SPSC, PSR, and organic P fertilizer application rate (OPR), with weights of 0.279, 0.233, 0.231, 0.097, and 0.084, respectively, were identified as the top five site characteristics with the highest weights explaining SP loss in tile discharge. These results highlighted the great contribution of both contemporary and legacy P sources to SP concentrations in tile discharge. Also, PI<sub>ANN </sub>was the only PI with a significant exponential relationship with measured annual SP concentrations (R<sup>2 </sup>= 0.60; p < 0.001). These findings demonstrated that MLF-ANNs coupled with Garson’s algorithm, can accurately quantify weights for individual site characteristics and develop PIs with a strong correlation with measured SP in tile discharge. Finally, in the third inquiry, we compared DRP loads and flow-weighted mean DRP (FDRP) concentrations in P source and P sink soils and evaluated the predominant DRP concentration – discharge (C-Q) behavior in these soils on a daily and event scale. At the daily scale, C-Q patterns were linked to the soil P status whereby a chemostatic and dilution behavior was observed for P source and P sink soils, respectively. At the event scale, C-Q patterns were linked to soil P status, flow path connectivity, and mixing of event water, matrix water, and rising shallow groundwater. The predominant anti-clockwise rotational pattern observed on P source soils suggested that, as the discharge event progressed, contributions from P poor waters including matrix and shallow groundwater resulted in lower DRP concentrations on the rising limb compared to the falling limb. However, the variable flushing and dilution behavior observed on the rising limb suggested that, in addition to discharge and soil P status, rapid exchanges between P pools, the magnitude of discharge events (Q), and the relative number of days to discharge peak (D<sub>rel</sub>) also regulated DRP delivery. On the other hand, the predominant non-hysteretic C-Q behavior in P sink soils suggest that DRP loss from these soils can be discounted. Our collective results highlight the need for nutrient and conservation practices focused on P drawdown, P sequestration, and P supply close to the crop needs, which will likely be required to convert P sources to sinks and to avoid the conversion of P sinks to sources. </p>
10

Exploring the Effects of Cover Crop Use on Farm Profitability in Central Indiana

Megan N. Hughes (8775677) 02 May 2020 (has links)
Cover crop use provides a myriad of benefits to soil health. Despite strong agronomic evidence of the benefits of using cover crops, farmers have been slow to adopt cover crop systems. Surveys show that this is due to a lack of understanding on how cover crop use will impact the farm, and limited economic analysis on the effects of cover crop use on the farm. <div> In this thesis, a variable-rate nitrogen study was analyzed to determine the relationship between applied nitrogen fertilizer and corn yields, and how a cover crop treatment impacts that relationship. Data were obtained from a case farm in Central Indiana. Production information was then translated into a partial budget to see how the use of the different cover crop treatments impacted net return per acre for corn production on the farm. Net returns were analyzed using both historical corn and nitrogen prices and stochastic modelling.</div><div> Results showed that the final impact on farm net return per acre associated with adoption of a cover crop system varies among cover crop species. Implementing annual rye resulted in a negative change to net return; while cereal rye and an oats and radish blend resulted in a positive change to net return. When additional benefits of cover crop use; such as drought tolerance, carbon content, and erosion reduction; are included, all three cover crop species resulted in a substantial increase in net return. This information will be of interest to farmers as a source to draw upon when making decisions regarding their own farms. Further research is needed to fully understand the relationship between cover crop use and farm profitability, particularly for farms at the early stages of adoption.</div>

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