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Full-Text Articles in Physical Sciences and Mathematics

Session 2: The Effect Of Boom Leveling On Spray Dispersion, Travis A. Burgers, Miguel Bustamante, Juan F. Vivanco Feb 2023

Session 2: The Effect Of Boom Leveling On Spray Dispersion, Travis A. Burgers, Miguel Bustamante, Juan F. Vivanco

SDSU Data Science Symposium

Self-propelled sprayers are commonly used in agriculture to disperse agrichemicals. These sprayers commonly have two boom wings with dozens of nozzles that disperse the chemicals. Automatic boom height systems reduce the variability of agricultural sprayer boom height, which is important to reduce uneven spray dispersion if the boom is not at the target height.

A computational model was created to simulate the spray dispersion under the following conditions: a) one stationary nozzle based on the measured spray pattern from one nozzle, b) one stationary model due to an angled boom, c) superposition of multiple stationary nozzles due an angled boom, …


Effects Of Agricultural Chemicals On Native Plants Of The Northern Great Plains, Gabrielle Bolwerk Jan 2023

Effects Of Agricultural Chemicals On Native Plants Of The Northern Great Plains, Gabrielle Bolwerk

Electronic Theses and Dissertations

Agricultural chemicals are ubiquitous on the Northern Great Plains landscape and have negative impacts on non-target plant communities, even at small doses. Northern Great Plains grassland plant communities may experience herbicide drift from agricultural fields or be subject to livestock pharmaceuticals in grazing lands. My research objective was to evaluate if and how native plants are affected by agricultural chemical presence at different concentrations. In Chapter 2, I studied the effect of different concentrations of three common agricultural herbicides (2,4-D, atrazine, and trifluralin) on the germination, emergence, and growth of native plant species of the Northern Great Plains. I performed …


Soil Hydro-Physical Properties, Computed Tomography Measured Pore Parameters, And Soil Health Indicators As Influenced By Tillage And Crop Rotation Systems, Goutham Thotakuri Jan 2022

Soil Hydro-Physical Properties, Computed Tomography Measured Pore Parameters, And Soil Health Indicators As Influenced By Tillage And Crop Rotation Systems, Goutham Thotakuri

Electronic Theses and Dissertations

Long-term tillage and crop rotation systems are important agricultural management practices as these can have direct impact on the soil’s key properties. The objectives of this study were to (ⅰ) quantify the soil pore characteristics under long-term tillage and crop rotation using X-ray computed tomography (XCT) and to assess the relationships between XCT-measured pore parameters and soil hydro-physical properties; and (ⅱ) evaluate the impacts of long-term tillage and crop rotation on select soil health indicators. The objective (ⅰ) was carried out at Haskell Agricultural Laboratory (HAL), Concord, NE; and objective (ⅰi) was carried out at South Central Agricultural Laboratory (SCAL), …


Using Deep Neural Networks To Analyze Precision Agriculture Data, Stephanie Liebl Jan 2022

Using Deep Neural Networks To Analyze Precision Agriculture Data, Stephanie Liebl

Electronic Theses and Dissertations

As the population of the Earth increases, there is a growing need for food to feed the inhabitants. Precision agriculture offers techniques and tools that can be used to help accommodate the growing population. One specific precision agriculture tool is remote sensing data, which can be used to image fields as an effort to better predict or understand the crops. In this thesis, deep neural networks are used to evaluate various spatial, spectral, and temporal resolutions of three different satellite images to determine which best predicts corn yield. The main metrics we used to evaluate the models were R-squared (R2), …


Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain Jan 2022

Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain

Electronic Theses and Dissertations

Conservation management practice adoption on agricultural land has increased in recent years due to increasing public and private investment. The anticipated impact of increasing conservation management practice adoption are reduced greenhouse gas emissions and improved soil, water, and air quality. Understanding how these conservation management practices affect agricultural producers economically is vital to properly incentivize these practices. The existing literature on how conservation management practices affect soil health and crop yields is mixed and generally has been conducted on experimental research stations. These studies may not fully account for the on-farm effects of conservation management practices. The objectives of this …


Regenerative Agriculture Effects On Invertebrate And Bird Communities And Insect-Provided Ecosystem Services, Alex Michels Jan 2022

Regenerative Agriculture Effects On Invertebrate And Bird Communities And Insect-Provided Ecosystem Services, Alex Michels

Electronic Theses and Dissertations

Conventional agricultural practices can have unintended consequences on the environment and wildlife. Insects and birds are declining at rapid rates around the world, and the current conventional agricultural paradigm is a major driver through habitat loss and the intensification of production. Invertebrates in agroecosystems provide services to both farmers and the rest of society. Regenerative systems may promote the functioning of an agroecosystem by influencing invertebrate abundance, diversity, and ecosystem services and mitigate bird and insect declines through conservation practices that increase soil health, reduce disturbances, and increase biological diversity. Here I address knowledge gaps of the effects of regenerative …


Phosphorus Use And Management Based On Fertilizer Placement, Rate Of Application, And Soil Biota In No-Till Situations, Brennan Alexander Bingham Lewis Jan 2022

Phosphorus Use And Management Based On Fertilizer Placement, Rate Of Application, And Soil Biota In No-Till Situations, Brennan Alexander Bingham Lewis

Electronic Theses and Dissertations

Phosphorus (P) pollution has become a concern among multiple scientific organizations as it leads to eutrophication, an algal bloom that depletes lacustrine and marine ecosystems of native species. Multiple strategies can be implemented to reduce phosphorus loss from agriculture fields, which is often implicated as a cause of eutrophication. Soil phosphorus chemistry results in phosphate fertilizers absorbing to clay minerals over time. Soil phosphorus is lost from agricultural fields primarily through wind and water erosion. No-till practices prevent soil erosion, which reduces the phosphorus from loading into waterways. Fertilizer placement affects phosphorus loss. Surface application of phosphorus fertilizers increases the …


South Dakota Farmers’ Perceived Extreme Weather Frequency And Adaptation Measures, Tong Wang, Jim Ristau Dec 2021

South Dakota Farmers’ Perceived Extreme Weather Frequency And Adaptation Measures, Tong Wang, Jim Ristau

South Dakota Farm Survey

Researchers at South Dakota State University (SDSU) conducted surveys of eastern South Dakota (SD) commodity crop producers with the support of the South Dakota Corn Utilization Council. Using publicly available addresses of government program participants, a random sample of 3,000 producers were sent the survey in 2018. 650 were ineligible and 708 responded to the survey for a response rate of 30%. In 2021, the same producers who took the survey in 2018 were asked to take a follow up survey. 94 were ineligible, and 350 responded for a 59% response rate. Producers could take the survey online or via …


Expanding Grass-Based Agriculture On Marginal Land In The U.S. Great Plains: The Role Of Management Intensive Grazing, Tong Wang, Hailong Jin, Urs Kreuter, Richard Teague May 2021

Expanding Grass-Based Agriculture On Marginal Land In The U.S. Great Plains: The Role Of Management Intensive Grazing, Tong Wang, Hailong Jin, Urs Kreuter, Richard Teague

Economics Faculty Publications

No abstract provided.


Exploring The Determinants Of Aspects Of Rotational Grazing In The U.S. Great Plains, Iftekhar Uddin Ahmed Chowdhury Jan 2021

Exploring The Determinants Of Aspects Of Rotational Grazing In The U.S. Great Plains, Iftekhar Uddin Ahmed Chowdhury

Electronic Theses and Dissertations

Pasture and rangeland make up about 45 percent of the agricultural land in the U.S. Great Plains and one of the most common form of mismanagement of this pasture is overgrazing. Which results in many detrimental effects on environment. Many practitioners endorsed Rotational grazing (RG) as an improved grazing management practice over season-long continuous grazing. The overall goal of the current study is to assess the certain aspects of using RG in the U.S. Great Plains. Using mail survey data of the of 874 beef cattle producers of North Dakota, South Dakota, and Texas, the study found that neighborhood practice, …


Burning With Potential: Understanding The Relationship Between Biochar And Agriculture Of The Northern Glaciated Plains Ecoregion, Kaitlyn Abrahamson Jan 2020

Burning With Potential: Understanding The Relationship Between Biochar And Agriculture Of The Northern Glaciated Plains Ecoregion, Kaitlyn Abrahamson

Electronic Theses and Dissertations

Achieving global sustainable agriculture is one of the most incredible challenges of this century, yet many continue to try to solve this problem through the development of precision technologies. Biotechnologies, such as biochar, can perform like a precision technology while protecting agricultural land from soil erosion and fertility loss. The Northern Glaciated Plains ecoregion of the United States is little researched in the benefits from the use of biochar through improved soil nutrient capture and water retention, crop health improvements, and yield increases. The study plot has four sections of corn stover biochar and eight sections of control sections. This …


Understanding How Agricultural Intensification Impacts Ring-Necked Pheasant Distribution And Survival In Eastern South Dakota, Hilary R. Kauth Jan 2020

Understanding How Agricultural Intensification Impacts Ring-Necked Pheasant Distribution And Survival In Eastern South Dakota, Hilary R. Kauth

Electronic Theses and Dissertations

Historically, pheasants (Phasianus colchicus) have thrived in South Dakota in conjunction with successful land retirement programs or early farming practices through the 1950s, which created interspersions of agriculture and native landscapes that were ideal for pheasants. Recently, the Prairie Pothole ecosystem has undergone rapid agroeconomic expansion, effectively reducing ideal interspersions of native prairie and cropland into agriculturally homogeneous landscapes. Indices of pheasant abundance have suggested persistent population declines since 2008, raising concerns regarding landscape suitability. Our goal was to understand how agriculture intensification impacts pheasant ecology. The objectives were to: 1) estimate overwinter hen probability of survival, resource …


Biophysical And Socioeconomic Impacts Of Farmer Managed Natural Regeneration In Burkina Faso, Basnewende Brice Fulgence Zoungrana Jan 2020

Biophysical And Socioeconomic Impacts Of Farmer Managed Natural Regeneration In Burkina Faso, Basnewende Brice Fulgence Zoungrana

Electronic Theses and Dissertations

Human actions such as overgrazing, the development of cities at the expense of forests, high intensity and poor agricultural management, and so forth, reduce the resources available for future generations. Because Earth has limited resources, it is important to judiciously use and manage natural resources. Human actions towards nature are the focus of my research in Africa. Increased demands for grazing, agriculture, and ecosystem services led some farmers in developing countries to use unsustainable practices, which may lead to low incomes and poor food nutrition for households. Farmer managed natural regeneration (FMNR) may be a solution to these issues. FMNR …


Understanding South Dakota Farmers’ Intentions To And Adoption Of Conservation Practices: An Examination Of The Theory Of Planned Behavior, Edem Avemegah Jan 2020

Understanding South Dakota Farmers’ Intentions To And Adoption Of Conservation Practices: An Examination Of The Theory Of Planned Behavior, Edem Avemegah

Electronic Theses and Dissertations

Conservation agriculture practice is a sustainable farming method based on three principle: crop diversification, minimal soil disturbance or movement and permanent or semi-permanent of soil cover. Government and stakeholders within the agricultural sector in the United States are promoting conservation farming practices but limited voluntary adoption still exists among producers at the farm level. This research study investigated the factors that influence the adoption of conservation practices among producers in the eastern and central parts of South Dakota (SD). A modified theory of planned behavior (TPB) is used as a framework alongside socioeconomic and demographic indicators to understand farmers’ current …


Chemical Amendments Of Dryland Saline–Sodic Soils Did Not Enhance Productivity And Soil Health In Fields Without Effective Drainage, Girma A. Birru, David E. Clay, Thomas M. Desutter, Cheryl L. Reese, Ann C. Kennedy, Sharon A. Clay, Stephanie A. Bruggeman, Rachel K. Owen, Douglas D. Malo Apr 2019

Chemical Amendments Of Dryland Saline–Sodic Soils Did Not Enhance Productivity And Soil Health In Fields Without Effective Drainage, Girma A. Birru, David E. Clay, Thomas M. Desutter, Cheryl L. Reese, Ann C. Kennedy, Sharon A. Clay, Stephanie A. Bruggeman, Rachel K. Owen, Douglas D. Malo

Agronomy, Horticulture and Plant Science Faculty Publications

A common restoration treatment for saline–sodic soils involves improving soil drainage, applying soil amendments (e.g., CaSO4, CaCl2, or elemental S), and leaching with water that has a relatively low electrical conductivity. However, due to high subsoil bulk densities and low drainable porosities, these treatments many not be effective in glaciated dryland systems. A 3-yr field study conducted in three model systems determined the impact of chemical amendments (none, CaCl2, CaSO4, and elemental S) on plant growth, microbial composition, temporal changes in electrical conductivity (ECe ), and the relative sodium content (%Na). …


Understanding Greenhouse Gases, Julie M. Mueller, Laura Edwards, Madhav P. Nepal, Larry B. Browning, Matthew L. Miller, P. Troy White Jan 2019

Understanding Greenhouse Gases, Julie M. Mueller, Laura Edwards, Madhav P. Nepal, Larry B. Browning, Matthew L. Miller, P. Troy White

iLEARN Teaching Resources

Students will conduct hands-on experiments to see how greenhouse gases interact with the Earth’s atmosphere and how greenhouse gases affect temperature. This lesson introduces National Geographic’s Geo-Inquiry Process, where students will identify a Geo-inquiry question, collect data, and create a project around the answer to their question. Students will then present their findings to their peers and evaluate their Geo-Inquiry process.


Using A Case Study Approach To Teach Invasive Species And Climate Change, Amanda Hoover, Bradley Blaha, Jacob Englin, Madhav P. Nepal, Larry B. Browning, Matt L. Miller, P. Troy White Jan 2019

Using A Case Study Approach To Teach Invasive Species And Climate Change, Amanda Hoover, Bradley Blaha, Jacob Englin, Madhav P. Nepal, Larry B. Browning, Matt L. Miller, P. Troy White

iLEARN Teaching Resources

In this teaching module, students will explore emerald ash borer (EAB), its impacts on the ash trees, and how warming temperatures could affect EAB populations. The emerald ash borer is a green buprestid or jewel beetle native to north-eastern Asia that causes devastating disease in ash trees.


Diversifying Cornfields By Interseeding Cover Crops: Practical Implications And The Response Of Invertebrate Communities, Michael Bredeson Jan 2019

Diversifying Cornfields By Interseeding Cover Crops: Practical Implications And The Response Of Invertebrate Communities, Michael Bredeson

Electronic Theses and Dissertations

The lack of suitable habitat conditions for beneficial organisms in simplified agroecosystems leads to unstable invertebrate communities and overreliance on chemical control of herbivores. It is possible to manage pest populations without agrichemicals by manipulating farmland so that herbivores are impaired by plant-driven bottom-up and enemy-driven top-down antagonisms. Interseeding cover crops between established crop rows is a method used by farmers to improve habitat suitability for natural enemies and hinder host-finding, feeding and movement by herbivores. Here I address three important research gaps related to interseeding cover crops. A calcium carbonate seed coating, used to improve seed-broadcasting efficiency, was tested …


Impacts Of Diverse Crop Rotations And Integrated Crop-Livestock System On Soil Quality In South Dakota, Atilla Polat Jan 2018

Impacts Of Diverse Crop Rotations And Integrated Crop-Livestock System On Soil Quality In South Dakota, Atilla Polat

Electronic Theses and Dissertations

Crop diversification can be beneficial in improving soil quality parameters. Diverse crop rotations and integrated crop-livestock systems (ICLS), are two examples of crop diversification used in this study to assess soil quality. The objectives of this study were to: (i) assess the impacts of diverse rotations on soil quality parameters, and (ii) assess the impacts of low and high stocking density on soil quality parameters. Both of the studies were conducted separately and are presented as two different chapters. To accomplish objective (i), a long-term experiment was selected which was established near Brookings, South Dakota, USA at USDA-ARS lab in …


Quantifying The Short-Term Impacts Of Cover Crops And Grazing On Soil Health Under An Integrated Crop-Livestock System In South Dakota, Vishal Seth Jan 2018

Quantifying The Short-Term Impacts Of Cover Crops And Grazing On Soil Health Under An Integrated Crop-Livestock System In South Dakota, Vishal Seth

Electronic Theses and Dissertations

Cover crops and grazing under Integrated Crop-Livestock System (ICLS) can impact the rhizosphere nutrient cycling and may have potential to increase the long-term sustainability and economic profitability of agricultural production system. In South Dakota, crop production practices and livestock husbandry are both common which provide the opportunity for ICLS to be successful in this region. However, little is known about the impacts of the cover crops and grazing under ICLS on soil properties in this region. The present study was conducted at South Dakota State University Research Farm (44°20'34.8"N, 96°48'14.8"W), Brookings, SD, to quantify the impacts of cover crops and …


Land Use Change Sustainability And Carbon Turnover Rate In The Northern Great Plains Soil, Deepak Raj Joshi Jan 2018

Land Use Change Sustainability And Carbon Turnover Rate In The Northern Great Plains Soil, Deepak Raj Joshi

Electronic Theses and Dissertations

Sustainable land management involves the management of land, water, biodiversity and other resources that meet human requirements while maintaining ecosystem services. In the northern Great Plains (NGP), the combined impacts of landuse and climate variability have placed many soils at the tipping point of sustainability. The objectives of this study were to: 1) calculate land-use changes from 2006 to 2012 and from 2012 to 2014 in South Dakota and Nebraska; 2) assess if land use changes had impacted on soil sustainability; 3) calculate variation in total carbon budget and turnover due to seasonal climate variability, biomass quality and soil properties; …


Interactive Effects Of Cover Crops, Invertebrate Communities And Soil Health In Corn Production Systems, Claire Lacanne Jan 2017

Interactive Effects Of Cover Crops, Invertebrate Communities And Soil Health In Corn Production Systems, Claire Lacanne

Electronic Theses and Dissertations

The adoption of regenerative farming practices is gaining traction, but the costs and benefits are not often considered on a systems level. Encouraging biodiversity and soil health is the goal of many agricultural practices used in regenerative farming; regenerative systems employ practices which abide by the two main principles of increasing biodiversity and decreasing disturbance, with the goal of encouraging ecosystem functioning to minimize inputs and maximize the productivity of a farm. I examined the management of corn (Zea mays) fields across four states in the Upper Midwest region of the United States. Regenerative systems in this study …


Heterogeneous Nitrogen Losses: Cost-Effectiveness Analysis Of Changes In Management Across South Dakota, Archibold Quaye Jan 2017

Heterogeneous Nitrogen Losses: Cost-Effectiveness Analysis Of Changes In Management Across South Dakota, Archibold Quaye

Electronic Theses and Dissertations

The loss of nitrogen fertilizer into the atmosphere and waterways is of increasing concern for citizens and policy makers. This is particularly relevant for hypoxia in rivers, lakes, and oceans, but also relevant for policy makers in reducing the increasing concentration of greenhouse gases (GHG) in the atmosphere. GHGs trap heat in the atmosphere and include: carbon dioxide, methane, nitrous oxide and fluorinated gases. Overall, the estimated contribution from the agricultural sector to GHG emissions was 9% in 2013 (EPA, 2013). Further, the addition of nitrogen to the soil through the use of synthetic fertilizers is a main contributor to …


Response Of Soil Properties To 23-25 Years Of Diverse Crop Rotations And Tillage Systems In South Dakota, Usa, Abdullah H. Alhameid Jan 2017

Response Of Soil Properties To 23-25 Years Of Diverse Crop Rotations And Tillage Systems In South Dakota, Usa, Abdullah H. Alhameid

Electronic Theses and Dissertations

Diverse cropping systems and no-till (NT) are beneficial in improving soil organic carbon (SOC) and other soils properties. The present study was conducted to evaluate the interactions and impacts of long-term tillage and diverse crop rotation systems on soil quality indicators that include a range of soil chemical, physical, hydrological, and microbial properties. The study was established in 1991 at Beresford, South Dakota and included three crop rotation systems [2-yr; maize (Zea mays L.)-soybean (Glycine max L.), 3-yr; maize-soybean-oat (Avena sativa L.), and 4-yr; maize-soybean-oat-wheat (Triticum aestivum L.)] managed under two tillage systems (NT and CT; conventional- tillage). Soil sampling …


A Demonstration Study Of Drainage Water Management In Eastern South Dakota, Ashik Sahani Jan 2017

A Demonstration Study Of Drainage Water Management In Eastern South Dakota, Ashik Sahani

Electronic Theses and Dissertations

Subsurface drainage is a common water management practice for improving crop production in poorly drained soils; however, the practice is associated with several environmental concerns such as nutrient losses to downstream surface waters. These environmental concerns from subsurface drainage have prompted interest in drainage water management strategies such as controlled drainage. This study assessed the agronomic and environmental impacts of drainage water management in eastern South Dakota by using two demonstration plots for controlled and conventional drainage. Drain flow, nitrate and dissolved phosphorous concentration in drain water, shallow groundwater, crop yield, residual soil nitrate, soil moisture and temperature, soil penetration …


Human Dimensions Of Habitat Loss In The Plains And Prairie Potholes Ecoregion, Lily A. Sweikert Jan 2017

Human Dimensions Of Habitat Loss In The Plains And Prairie Potholes Ecoregion, Lily A. Sweikert

Electronic Theses and Dissertations

The Plains and Prairie Potholes Ecoregion (PPPE), is located in the north-central contiguous United States and is one of the most imperiled grassland regions in the world. Most of the region is privately owned and used for the production of agricultural commodities. In addition to its direct benefits to humanity, the PPPE provides multiple ecosystem services including, soil and water quality improvements, carbon sequestration, weather amelioration, and wildlife habitat. Recent increases in expansion of row crop agriculture concerns conservation practitioners about the long-term integrity of the PPPE. Conservation practitioners are looking to improve their private landowner conservation initiatives in the …


Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez Jan 2017

Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez

Electronic Theses and Dissertations

Irrigation water is scarce. Hence, accurate estimation of crop water use is necessary for proper irrigation managements and water conservation. Satellite-based remote sensing is a tool that can estimate crop water use efficiently. Several models have been developed to estimate crop water requirement or actual evapotranspiration (ETa) using remote sensing. One of them is the Mapping EvapoTranspiration at High Resolution using Internalized Calibration (METRIC) model. This model has been compared with other methods for ET estimations including weighing lysimeters, pan evaporation, Bowen Ratio Energy Balance System (BREBS), Eddy Covariance (EC), and sap flow. However, comparison of METRIC model outputs to …


Comprehensive Structural, Thermal And Toxicological Characterization Of 1-Ethyl-3-Methylimidazolium Alkylbenzenesulfonate Ionic Liquids, Hiranmayee Kandala Jan 2017

Comprehensive Structural, Thermal And Toxicological Characterization Of 1-Ethyl-3-Methylimidazolium Alkylbenzenesulfonate Ionic Liquids, Hiranmayee Kandala

Electronic Theses and Dissertations

Synthesis and characterization of 1-ethyl-3- methylimidazolium alkylbenzenesulfonate ionic liquids for extraction of lignin from prairie cord grass have been studied. The ionic liquids (ILs) 1-ethyl-3- methylimidazolium benzenesulfonate (EBS), 1-ethyl-3- methylimidazolium toluenesulfonate (ETS) and 1-ethyl-3- methylimidazolium xylenesulfonate (EXS) have been synthesized in this research. An extensive structural, physical, thermal and toxicological characterization has been performed to understand the behavior of these ionic liquids. The reaction yield for the synthesis of EBS, ETS, and EXS ionic liquids was determined to be 91.2 ± 1.5 %, 96.1 ± 0.7 %, 99.0 ± 0.5 % respectively. Spectral analysis using NMR and FTIR confirms the …


Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaled Modis Vegetation Indices Improve Performance?, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiaoyang Zhang, Andrew Suyker, Shashi Verma, Yanmin Shuai, Elizabeth M. Middleton Jan 2015

Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaled Modis Vegetation Indices Improve Performance?, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiaoyang Zhang, Andrew Suyker, Shashi Verma, Yanmin Shuai, Elizabeth M. Middleton

GSCE Faculty Publications

Satellite remote sensing estimates of gross primary production (GPP) have routinely been made using spectral vegetation indices (VIs) over the past two decades. The Normalized Difference Vegetation Index (NDVI), the Enhanced Vegetation Index (EVI), the green band Wide Dynamic Range Vegetation Index (WDRVIgreen), and the green band Chlorophyll Index (CIgreen) have been employed to estimate GPP under the assumption that GPP is proportional to the product of VI and photosynthetically active radiation (PAR) (where VI is one of four VIs: NDVI, EVI, WDRVIgreen, or CIgreen). However, the empirical regressions between VI*PAR and …


Drivers Of Agricultural Land Use Change And Management Decisions In The Dakotas: The Influence Of Climate Change And Other Factors, Moses Luri Jan 2015

Drivers Of Agricultural Land Use Change And Management Decisions In The Dakotas: The Influence Of Climate Change And Other Factors, Moses Luri

Electronic Theses and Dissertations

This thesis conducts a general assessment of the: main drivers of land use change; recent and projected land use patterns; and the evolution of agriculture in the Dakotas. Specifically, it determines the main motives of land use change in the Dakotas by investigating individual and joint effects of external drivers of land use change on farm operators’ decisions and also examines recent and projected agricultural land use patterns in the Dakotas. Farm operators’ perceptions about the evolution of agriculture in the Dakotas based on observed changes in their local area were also analyzed. The study region consists of 37 counties …