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South Dakota State University

Electronic Theses and Dissertations

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Development Of Innovative Flocculation Technologies For Agricultural Water Treatment, Noor Haleem Jan 2024

Development Of Innovative Flocculation Technologies For Agricultural Water Treatment, Noor Haleem

Electronic Theses and Dissertations

The development of innovative flocculation technologies is essential for addressing the challenges of agricultural water treatment. These technologies play a crucial role in removing contaminants such as suspended solids and nutrients, thereby ensuring safer water for irrigation and livestock consumption. By enhancing water quality and wastewater management, they contribute significantly to environmental sustainability and public health in agricultural communities. This comprehensive thesis extensively explores various dimensions of flocculation, with a focused effort on methodologies and resources aimed at strengthening sustainability and efficiency. A pivotal aspect of the research involves synthesizing cationic starch (CS), a flocculant derived from an underutilized resource, …


Physicochemical And Functional Properties Of Different Varieties Of Spring And Winter Peas Of South Dakota, Prakriti Dhakal Jan 2024

Physicochemical And Functional Properties Of Different Varieties Of Spring And Winter Peas Of South Dakota, Prakriti Dhakal

Electronic Theses and Dissertations

Peas are a good source of nutrients for both humans and animals, and they are the world's second most significant and sustainable legume. There have been studies on different kinds of pea grown in other parts of the world, but there is no information on the compositional and functional characteristics of pea varieties grown specifically in South Dakota. The objective of the study was to evaluate the proximate composition and functional properties of various pea varieties and determine if the pea variety impacted cookie properties. The proximate composition (moisture, protein, starch, and amylose), functional capacities (water holding, oil holding capacity, …


Effects Of Storage Regimes On Chemistry, Functional Properties, And Vitamin Profile Of Different Varieties Of Chickpea, Shirin Kazemzadeh Pournaki Jan 2024

Effects Of Storage Regimes On Chemistry, Functional Properties, And Vitamin Profile Of Different Varieties Of Chickpea, Shirin Kazemzadeh Pournaki

Electronic Theses and Dissertations

Chickpea (cicer arietinum) samples from five distinct varieties (crown, royal, orion, sierra, and frontier) were subjected to varying storage conditions to investigate the impact of temperature and relative humidity (rh) on their chemical, functional, physical properties, and vitamin b profile. over 360 days, samples were stored at two temperatures (21°c and 40°c) and three rh levels (40%, 55%, 65%), with collections made every 90 days. initial observations focused on key chemical properties including moisture, protein, fat, and total starch content. subsequently, protein and starch fractions were isolated for further analysis, employing techniques such as sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) …


Advancing Biological Applications Through Microfluidic-Based Tool Development, K.M. Taufiqur Rahman Jan 2024

Advancing Biological Applications Through Microfluidic-Based Tool Development, K.M. Taufiqur Rahman

Electronic Theses and Dissertations

This research undertook an interdisciplinary approach, integrating bioengineering, microbiology, molecular biology, and systems biology to investigate bacterial dynamics behavior. Specifically, it delved into the development of microfluidic devices for biological applications such as bacterial cell counts, real-time observation of plant roots (here, specialized lectin-coated microbeads are used that mimic root characteristics), and soil microbe interactions. Furthermore, Next-Generation Sequencing and systems biology methodologies were employed to explore the intricate, multifaceted survival mechanisms of Escherichia coli persister population. Studying and quantifying persisters or testing for the existence of VBNC (viable but nonculturable) is challenging. These experiments require precise counts. It has been …


Utilizing Soil Sensors To Assess Soil Health And Investigating Cover Crops Impact On Methane Emission, Shailesh Pandit Jan 2024

Utilizing Soil Sensors To Assess Soil Health And Investigating Cover Crops Impact On Methane Emission, Shailesh Pandit

Electronic Theses and Dissertations

Soil health is influenced by climate change, cultural practices, topography, crop rotations, cover crops, soil parent materials, and soil biota. Interactions between these factors can improve or reduce soil health. This thesis investigates two topics, using soil sensors to provide a rapid assessment of soil health, and the impact of cover crops on soil biological activity and greenhouse gas emissions. Chapter 1 explores the use of two types of sensors to measure apparent electrical conductivity (ECa) and provides examples on the use of these sensors. Even though both sensors measure ECa using different processes, they provide useful information about temporal …


Integrating Early Season Clover Cover Crops As A Living Mulch In Broccoli And Transitional Organic Winter Squash Production In Eastern South Dakota, Alexis Rose Barnes Jan 2024

Integrating Early Season Clover Cover Crops As A Living Mulch In Broccoli And Transitional Organic Winter Squash Production In Eastern South Dakota, Alexis Rose Barnes

Electronic Theses and Dissertations

Managing weeds, improving soil health, and reducing the use of plastic mulch continue to be priorities for South Dakota vegetable farmers. Farmers have expressed an interest in integrating cover crops into their farm systems. Clover cover crops used as a living mulch within and along cash crop rows may aid in weed suppression, nitrogen fixation, and prevent soil erosion. However, prior research has shown challenges of incorporating living mulch due to yield decreases. Research conducted in 2022 and 2023 in eastern South Dakota investigated the effects of four clover and four in-row soil management treatments on broccoli and organic winter …


Nitrogen Application Timing And Cereal Rye (Secale Cereale L.) Cover Crop Influence Greenhouse Gas Emissions, Graig Reicks Jan 2024

Nitrogen Application Timing And Cereal Rye (Secale Cereale L.) Cover Crop Influence Greenhouse Gas Emissions, Graig Reicks

Electronic Theses and Dissertations

Dryland contributions to greenhouse gas (GHG) emissions are increased by N fertilizer applications and high soil water contents. Fertilizer timing and spring growth of cover crops prior to cash crop planting were investigated in separate studies to examine impacts on overall GHG emissions using a near continuous measurement system. There was a significant interaction between N fertilizer rate (0 vs. 224 kg N ha-1 surface-applied as urea) and application date (p= 0.01) for CO2 emissions. This interaction occurred because N fertilizer increased CO2 emissions by 35% for the 21 d interval following early spring application. When application was delayed until …


Portable X-Ray Fluorescence Spectrometry For Sensing Salinity And Sodicity In Glacial Northern Great Plains Soils With Machine Learning Models, Adam Devlin Jan 2024

Portable X-Ray Fluorescence Spectrometry For Sensing Salinity And Sodicity In Glacial Northern Great Plains Soils With Machine Learning Models, Adam Devlin

Electronic Theses and Dissertations

Saline and sodic soils are an increasing concern across the Northern Great Plains (NGP) due to factors of climate change and land management that are drawing geologically derived salts to the land surface. Traditional laboratory assessments, such as electrical conductivity (EC) and sodium adsorption ratio (SAR), are time and resource consumptive. Portable X-ray fluorescence (PXRF) may be a viable proximal sensing alternative, as it is able to provide elemental data in minutes, in situ or ex situ, and can directly quantify salinity-associated elements like Ca, Mg, and S. PXRF paired with predictive models has proven useful for a range of …


The Hutton Project: Long-Term Agricultural Impacts On Soil Loss And Carbon Dynamics In Eastern South Dakota, Eli Halverson Jan 2024

The Hutton Project: Long-Term Agricultural Impacts On Soil Loss And Carbon Dynamics In Eastern South Dakota, Eli Halverson

Electronic Theses and Dissertations

Long-term and intensified agricultural land management has resulted in increased rates of soil erosion and has altered much of the carbon cycle at regional and global scales. Anthropogenic degradation of soil resources is a barrier to sustainable production, soil functioning, and ecosystem services. It is difficult to quantify the scope of pedogenic changes due to the lack of legacy data and short temporal scales. This study utilized decades to century-old soil information to quantify historical soil erosion losses and changes in soil carbon pools of eastern South Dakota soils. The results show that soils in the region have been significantly …


Developing Machine Learning Models For Selection Of Management Zones, Sravanthi Bachina Jan 2024

Developing Machine Learning Models For Selection Of Management Zones, Sravanthi Bachina

Electronic Theses and Dissertations

Soil sampling and analyses play a crucial role in optimizing nutrient management and enhancing crop productivity. However, collecting representative samples across diverse landscapes is challenging due to knowledge gaps about spatial variability of soil properties, large fields, multiple samples, and analysis costs. Collecting soil samples based on the management zones can help farmers gather precise information about soil properties with fewer samples. Recent developments in precision agriculture and machine learning. This study aimed to develop machine learning models that can learn, analyze, and refine landscape and soil properties data for automated selection of soil sampling zones and generating prediction maps. …


Longevity In Afrikaner Cattle: A Survival Analysis, Allison M. Bot Steffl Jan 2024

Longevity In Afrikaner Cattle: A Survival Analysis, Allison M. Bot Steffl

Electronic Theses and Dissertations

The Afrikaner breed of cattle is indigenous to South Africa and due to their hardiness was once the most popular breed amongst farmers. The objectives for this study were to: (1) estimate environmental effects (age at first calving, season) and (2) genetic variance affecting longevity in Afrikaner cattle using survival analysis and a Weibull model and (3) evaluate the effect of the Infusion Project on longevity utilizing a Cox model. For the first objective, age at first calving impacted longevity as younger age at first calving was associated with decreased longevity. Season of birth and year of birth also impacted …


Influence Of Reduced Salt In Fully Cooked Ham And Sausage Cured With Natural Celery Powder On The Growth Of Listeria Monocytogenes At 4⁰C, Anne Sherod Jan 2024

Influence Of Reduced Salt In Fully Cooked Ham And Sausage Cured With Natural Celery Powder On The Growth Of Listeria Monocytogenes At 4⁰C, Anne Sherod

Electronic Theses and Dissertations

This research evaluated the influence of reducing salt on outgrowth of L. monocytogenes on ready to eat (RTE) deli-style sliced ham cured with natural celery powder, fully cooked sausage links cured with traditional sodium nitrite and sausage links cured with natural celery powder, vacuum packaged and stored at 4⁰C on the outgrowth of L. monocytogenes. Experiment 1 evaluated L. monocytogenes outgrowth on ham over 153 days on the following treatments, current retail ham (HC) 2.0% salt; reduced salt 1 (HRS1) 1.5% salt; reduced salt 2 (HSR2) 1.35% salt; and reduced salt 2 without antimicrobials (HRS2WA) 1.35% salt without potassium lactate …


Evaluation Of Dietary Fiber Technologies In Sow Diets, Garrin Shipman Jan 2024

Evaluation Of Dietary Fiber Technologies In Sow Diets, Garrin Shipman

Electronic Theses and Dissertations

Various technologies and alternative ingredients are being developed to increase the nutrient value of fibrous feedstuffs, improve animal performance, and promote sustainable swine production. Fiber-degrading enzymes have been extensively studied in growing pigs, with few studies focused on gestating sows. When considering gestating sows have greater energy digestibility of fibrous feedstuffs than grower pigs, the efficacy of fiber-degrading enzymes needs to be determined for implementation in commercial sow diets. As fiber inclusion in gestation diets benefits sow performance, corn dried distiller grains with solubles (DDGS) are a candidate fiber source for gestation alternative energy ingredient. Functional fibers, such as yeast …


Valuation Of Soybean Meal Versus Distillers Co-Products As A Protein Supplement For Finishing Beef Cattle: Effects On Growth Performance, Carcass Characteristics, And Efficiency Of Dietary Net Energy Utilization, Cassidy R. Rose Jan 2024

Valuation Of Soybean Meal Versus Distillers Co-Products As A Protein Supplement For Finishing Beef Cattle: Effects On Growth Performance, Carcass Characteristics, And Efficiency Of Dietary Net Energy Utilization, Cassidy R. Rose

Electronic Theses and Dissertations

Two randomized complete block design experiments were conducted to: 1) examine the effects of soybean meal with or without additional soybean hulls in replacement of modified corn distillers grains plus (MDGS) solubles on growth performance efficiency of dietary net energy utilization and carcass traits responses in finishing beef steers, 2) determine if partial or complete replacement of dried distillers grains plus solubles (DDGS) with solvent-extracted soybean meal (SBM) in diets based upon high-moisture ensiled corn influences growth performance, efficiency of dietary net energy utilization, sera urea-N (SUN) concentrations, or carcass traits in finishing beef steers. Experiment 1 was a 118-d …


Nutrient Intake, Performance, And Body Composition In Preseason Wrestlers, Gregory Coapstick Jan 2024

Nutrient Intake, Performance, And Body Composition In Preseason Wrestlers, Gregory Coapstick

Electronic Theses and Dissertations

BACKGROUND: College athletes, especially in weight class sports, often experience energy deficits. Weight class sports such as wrestling are at greatest risk for deficiencies, and little is known about the relationships between body composition, nutrient intake, and performance in these athletes.
OBJECTIVES: The purposes of this study were to quantify macronutrient and micronutrient intake of pre-season male collegiate wrestlers and compare to recommendations, and examine relationships among nutritional intakes, body composition, and performance measurements of strength, anaerobic, and aerobic capacity.
METHODS: Male Division I wrestlers (n=11, mean ± SD age: 21.3±1.7 years, wrestling experience: 14.9±2.5 years) were recruited during preseason. …


The Relationship Of Macronutrient Intake With Growth In Children With Type 1 Diabetes Mellitus, Jessica L. Freeling Jan 2024

The Relationship Of Macronutrient Intake With Growth In Children With Type 1 Diabetes Mellitus, Jessica L. Freeling

Electronic Theses and Dissertations

Child growth, a sensitive metric of overall health, results from the intricate interplay of nature and nurture. While the importance of nutrition in child growth is well established, growth trajectories exhibit substantial individual variability, influenced by sex and age, and often characterized by nonlinear patterns. Inadequate nutrition or disease can hinder growth, with potential for recovery upon proper nutrition or acute disease resolution. However, chronic disease or persistent malnutrition may lead to permanent growth perturbation. Notably, before the advent of insulin, chronic stunting and wasting were hallmarks of Type 1 diabetes mellitus (T1DM), though the specific impacts under modern standard …


Effects Of Low-Cost, Low-Tech Tools For Riparian Restoration On Prairie Streams In Western South Dakota, James Andrew Joseph Bolyard Jan 2024

Effects Of Low-Cost, Low-Tech Tools For Riparian Restoration On Prairie Streams In Western South Dakota, James Andrew Joseph Bolyard

Electronic Theses and Dissertations

Despite making up less than two percent of the overall landscape in the arid and semi-arid western US, riparian areas are a crucial resource for agriculture, livestock, and wildlife. However, many have impaired function and reduced riparian cover. Low-Cost, Low-Tech Tools (LCLTT) are a subset of Process-Based Restoration (PBR) used for riparian restoration that were chosen for their cost-effectiveness and minimal technical requirements. LCLTT has been tested in mountainous areas of the western US but only recently implemented in the Northern Great Plains (NGP). Given their novelty as an approach toward restoration for the region, professional restoration and landowner communities …


Species Distribution Modeling Of Aquilegia Brevistyla (Ranunculaceae): A Critically Imperiled Black Hills Disjunct Species, Eric Daniel Puetz Jan 2024

Species Distribution Modeling Of Aquilegia Brevistyla (Ranunculaceae): A Critically Imperiled Black Hills Disjunct Species, Eric Daniel Puetz

Electronic Theses and Dissertations

Unchecked human activity is contributing to rising levels of greenhouse gas emissions, changes in land use, altered disturbance/fire regimes, spread of invasive species, and loss of biological diversity and related breakdown of ecosystem services. Additionally, climatic shifts may lead to phenological mismatches between species and their environments if these changes outpace a species’ ability to adapt or migrate to a more suitable habitat. Isolated mountain populations are particularly threatened by unpredictable climatic conditions, as they may have limited migration corridors and often lower levels of genetic diversity to move or adapt, respectively. As these negative feedbacks compound on the landscape, …


Estimating South Dakota’S Capacity To Meet K-12 School Meal Fruit And Vegetable Requirements With State-Grown Produce, Bridgette Bienias Jan 2024

Estimating South Dakota’S Capacity To Meet K-12 School Meal Fruit And Vegetable Requirements With State-Grown Produce, Bridgette Bienias

Electronic Theses and Dissertations

Objective: Quantify South Dakota (SD)’s capacity to procure locally-sourced fruit and vegetables (FVs) for K-12 school meals.
Methods: Secondary analysis of 2017 SD agricultural census and school meal data. Yields were converted to edible cups of FVs using school meal guidelines provided by the U.S. Department of Agriculture. Student enrollment and meal redemptions were used to estimate the number of FV cups needed.
Results: Estimated SD FV production met minimum total K-12 cup requirements, except for total fruit (66%) and dark green vegetables (80%). Legumes supplied 77% of the total cups of vegetables produced in 2017, whereas dark green vegetables …


The Spatial Ecology Of Plains Spotted Skunks In South Dakota: Insights From Species Distribution, Resource Selection, And Co-Occurrence Models, Kara M. White Jan 2024

The Spatial Ecology Of Plains Spotted Skunks In South Dakota: Insights From Species Distribution, Resource Selection, And Co-Occurrence Models, Kara M. White

Electronic Theses and Dissertations

The plains spotted skunk (Spilogale interrupta) is a data-deficient small carnivore native to the central plains of North America that has experienced significant population declines. My dissertation investigates the species’ distribution, habitat associations, and interspecific interactions in South Dakota, providing crucial information for conservation actions. In Chapter 1, I developed ensemble distribution models on a broad scale, incorporating species location data from 1985–2020, environmental factors, and six predictive modeling algorithms. I identified key predictors including mean temperature diurnal range and proportion of area as pasture, and estimated ~31,300 km2 of potential habitat, predominately in eastern South Dakota. In Chapter 2, …


Regional Assessment Of Live Cattle And Carcass Characteristics In The Northern Plains, Harlee A. Brauckmuller Jan 2023

Regional Assessment Of Live Cattle And Carcass Characteristics In The Northern Plains, Harlee A. Brauckmuller

Electronic Theses and Dissertations

The goal of this project was to perform a regional assessment of live cattle and carcass characteristics in the northern plains. The assessment audited three packing plants to assess fed cattle, cow, and bull production. The live animal factors evaluated were transportation, mobility of cattle, identification, brands, and mud/manure present. Data collected during the slaughter process was bruising, dentition, and offal condemnations. In fed cattle yield grade, quality grade, and hot carcass weight were assessed. In cows and bulls muscle score and fat color score were assessed. To assess differences between cattle in the Northern Plains and cattle in the …


Characterizing Vaginal Gene Expression In Prepubertal Gilts, Shannon Lee Dierking Jan 2023

Characterizing Vaginal Gene Expression In Prepubertal Gilts, Shannon Lee Dierking

Electronic Theses and Dissertations

The best-known predictor of reproductive success in gilts is the age at puberty. Early puberty (i.e., d170 – d180 of age) is associated with improved long-term reproductive performance and more full value offspring for market. The ability to predict, in the prepubertal stage, the age that a replacement gilt would be expected to achieve puberty has great reproductive and economic advantages. This work focuses on identifying biological markers that are potentially predictive of age at puberty. Study 1 identified changes in the vaginal epithelium during gilt reproductive development. Pre-pubertal gilts (n =13) were followed from d70 of age until first …


Relating Predator Community Ecology And Duck Nest Survival In Eastern South Dakota, Samantha R. Fino Jan 2023

Relating Predator Community Ecology And Duck Nest Survival In Eastern South Dakota, Samantha R. Fino

Electronic Theses and Dissertations

As conversion of native grasslands and wetlands to croplands continues in the Prairie Pothole Region (PPR), managers are tasked with maintaining sustainable waterfowl populations. Mesopredator community dynamics is a hypothesized mechanism driving spatiotemporal variation of waterfowl nest survival in the PPR, yet studies often lack detailed information on mesopredator species occurrence and abundance. Therefore, understanding spatial and temporal variation in behaviors of mesopredators provides valuable insights for understanding predator-prey interactions between mesopredators and upland duck nests. Further, differences in a predator community resulting from lethal removal of dominant species may influence composition and space use patterns of subordinate and non-target …


Evaluation Of Yeast Postbiotic In Sow Diets On Sow And Offspring Performance And Microbial Succession, Joel Kieser Jan 2023

Evaluation Of Yeast Postbiotic In Sow Diets On Sow And Offspring Performance And Microbial Succession, Joel Kieser

Electronic Theses and Dissertations

Litter size and the resulting nutritional demand on the sow continue to increase while sow mortality and culling rate are also increasing. Non-nutritive feed additives may enhance sow health and thereby improve offspring growth and productivity after weaning. Development of the gut microbiome in piglets via microbial succession is critical for maximizing their productivity and providing stability for overcoming weaning stress. The objective of this study was to evaluate the impact of yeast-based postbiotic supplementation in gestation and lactation diets on offspring performance through the nursery period and on whether a yeast postbiotic could impact the sow fecal microbiome as …


Effect Of Lighter (273 Kg) And Heavier (356 Kg) Initial Weight On Growth Performance Of Single-Source, Pre-Conditioned Beef Steers Fed A Single Growing-Finishing Diet, Thomas C. Norman Jan 2023

Effect Of Lighter (273 Kg) And Heavier (356 Kg) Initial Weight On Growth Performance Of Single-Source, Pre-Conditioned Beef Steers Fed A Single Growing-Finishing Diet, Thomas C. Norman

Electronic Theses and Dissertations

The objective of the study was to determine the influence that initial BW has on growth performance responses, efficiency of dietary net energy (NE) utilization, and carcass traits in feedlot steers. Light- and heavy-weight Charolais×Red Angus steers (n = 70) selected from a larger single-source group were used in a 209-d growing-finishing feedlot experiment at the Ruminant Nutrition Center, in Brookings, SD. On d-0 and d-1 weight and hip height (HH) measurements were collected for allotment purposes; the initial experimental weight was the average between d 0 and d 1 BW. Steers were assigned to two groups based on initial …


The Role Of Cadherins And Ryk On Metastasis And Invasion In Triple Negative Breast Cancer Cell Model: Hs578t/Hs578ts(I)8, Ibis Iser Jan 2023

The Role Of Cadherins And Ryk On Metastasis And Invasion In Triple Negative Breast Cancer Cell Model: Hs578t/Hs578ts(I)8, Ibis Iser

Electronic Theses and Dissertations

Breast cancer is a major cause of death among women in European and North American countries, even with improved methods for diagnosis and therapy. The mortality of breast cancer is mainly due to the migration of the primary tumor to distinct sites in the body and is very common in triple negative breast cancer (TNBC). This type of breast cancer affects younger woman and has a high recurrence rate. Unfortunately, TNBC is extremely difficult to control because of the absence of specific targets for treatment. Therefore, our research aim is to discover new therapeutic targets and identify novel approaches for …


Application Of Crispr/Cas9 Whole Genome Screens To Advance Macrophage Biology, Kevin Wanniarachchi Jan 2023

Application Of Crispr/Cas9 Whole Genome Screens To Advance Macrophage Biology, Kevin Wanniarachchi

Electronic Theses and Dissertations

Advances in CRISPR/Cas9 gene editing technologies present opportunities to better understand the contribution of individual genes to complex eukaryotic cellular processes. I have applied CRISPR whole genome screen technologies to inform further mechanistic understanding of macrophage fitness and neutral lipid metabolism. This work is important because macrophages play critical roles in immune function and are implicated as causative agents in disease states. Chapter One of this dissertation provides insights into how CRISPR genome screening technologies have improved biological discovery and key findings from their application and discusses how this technology can be implemented to advance the discovery of novel macrophage …


Soil Profile Properties And Greenhouse Gas Emissions As Influenced By Long-Term Cattle Manure And Inorganic Fertilizer Applications Under Corn-Soybean-Spring Wheat Rotation In Eastern South Dakota, Anuoluwa Ojonoka Sangotayo Jan 2023

Soil Profile Properties And Greenhouse Gas Emissions As Influenced By Long-Term Cattle Manure And Inorganic Fertilizer Applications Under Corn-Soybean-Spring Wheat Rotation In Eastern South Dakota, Anuoluwa Ojonoka Sangotayo

Electronic Theses and Dissertations

The application of manure and inorganic fertilizer in row crops may significantly influence soil and greenhouse gas (GHG) emissions. Understanding the long-term influence of these management practices on soil pore characteristics, hydro-physical properties and greenhouse gas emission is essential in developing proper conservation practices. However, there is limited information on the impact of cattle manure and inorganic fertilizer application on soil hydro-physical properties, soil pore characteristics at lower depths and surface GHGs emissions. Therefore, the objectives of this study were to; (i) utilize X-ray computed tomography (XCT) technique to quantify the impact of manure and fertilizer amendments under a corn …


Factors Influencing Mortality Of Bighorn Sheep (Ovis Canadensis), Emily Moberg Jan 2023

Factors Influencing Mortality Of Bighorn Sheep (Ovis Canadensis), Emily Moberg

Electronic Theses and Dissertations

Reintroduced bighorn sheep (Ovis canadensis) in Nebraska faced a devastating pneumonia epizootic resulting in variable ewe reproductive success and poor lamb recruitment in many of the herds. From 2015-2017, no lamb recruitment was observed in the northern Pine Ridge subpopulation and as many as 60% of adults died. This was in stark contrast to the healthier Wildcat Hills herds to the south, where lamb recruitment was estimated to be between 50-70% during the same years. From 2018-2020, we radio-collared and recaptured 76 adult female bighorn sheep from 2 of 3 Pine Ridge herds and 1 of 2 Wildcat Hills herds. …


Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel Jan 2023

Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel

Electronic Theses and Dissertations

Understanding soil N transformations in agricultural systems of the Northern Great Plains is crucial for guiding effective soil and nutrient management of this vital cropland. While the use of biochar in agriculture has attracted great attention recently, little has been reported on the seasonal dynamics of soil nitrogen (N) transformation and its response to biochar application. A field experiment was conducted over 2 seasons, spring (6/3/19-6/24/19) and summer (7/26/19-8/16/19), using four treatments or control soil, urea (224 kg N/ha), biochar (46,250 kg/ha), and urea+biochar (224 kg N/ha and 46,250 kg/ha, respectively). The results for both seasons showed biochar had no …