Digital Commons Network^™

Comparing Metabolism And Hypoxia Tolerance Of Native And Non-Native Florida Freshwater Fishes In Climate Change Scenarios, Benjamin A. Share

All HCAS Student Capstones, Theses, and Dissertations

As climate change brings rising water temperatures and lower dissolved oxygen (DO) concentrations to freshwater bodies, it has become increasingly important to understand how this will affect ecosystems with established non-native or invasive species. Fishes of the family Cichlidae are the most pervasive non-native fishes in the Everglades and may increase their range further north under a changing climate. To better understand potential invasibility and competition with native fishes, the metabolism and hypoxia tolerance of non-native Blue Tilapia Oreochromis aureus was compared to native Bluegill Lepomis macrochirus when acclimated across a range of seasonal and projected temperatures. Intermittent-flow respirometry was …

Northern Great Plains Native Seed Strategy, Lora Perkins, Amy Symstad, Jennifer Zavaleta-Cheek, Emily Rohrer, Krista Ehlert

Native Plant Initiative Newsletters and Reports

Developed by the Northern Great Plains Native Seed Partnership

Land Cover Effects On Stream Water Chemistry In The Upper Saline River Watershed, Brandy Everett

Graduate Theses and Dissertations

Non-point source (NPS) pollutants and the conversion of natural areas to anthropogenic uses are one of the most critical stressors on water quality. The Upper Saline River Watershed has seen an increase in anthropogenic land cover over the last two decades, leading it to be previously identified as a 319 NPS priority watershed in Arkansas. This study used publicly available data to assess the magnitude and trends of total nutrients (TN and TP) at both the watershed and site level scale. Results suggest a decrease of 2.6%/yr in TN concentrations and 1.5%/yr in TP concentrations at the watershed scale. While …

Impact Of Irrigation Systems On Water Use And Water Productivity: A Case Study Using Aquacrop In Khartoum, Sudan, Abdalhakam Almagzoop

Department of Agricultural and Biological Systems Engineering: Masters Project Reports

Water scarcity significantly challenges agricultural productivity in arid regions like Khartoum, Sudan. This study evaluates the impact of three irrigation systems—furrow, sprinkler, and surface drip—on the water use and productivity of sorghum (Sorghum bicolor L.) under different climatic conditions using the AquaCrop model. Simulations were conducted for three representative years: a wet year (2022), a normal year (2015), and a dry year (2018). The results demonstrate that irrigation substantially improved water use efficiency and crop yield compared to non-irrigated (rainfed) conditions. Rainfed crops resulted in lower biomass, harvest index, and yield, particularly in the dry year, highlighting the importance …

Enhancing Water Sustainability In North Africa: Literature Review And Synthesis Of Current Knowledge Gaps In Sudan, Osman M. A. Adam

Department of Agricultural and Biological Systems Engineering: Masters Project Reports

This study delves into the critical role of groundwater in addressing global water challenges, with a focus on the Nubian Sandstone Aquifer System (NSAS) in north Africa. Groundwater constitutes a source of potable water, irrigation, and industrial use, especially in arid regions where surface water is limited. We analyzed the status of water quantity, withdrawals, recharge, and geological characteristics in the NSAS, specifically in Sudan, Egypt, and Libya. Though the NSAS is largely an untapped resource, water withdrawals from the NSAS in Egypt, Sudan, and Libya are projected to increase substantially from 2000 to 2100 due to population growth, with …

Net Evaporation-Induced Mangrove Area Loss Across Low-Lying Caribbean Islands, Isamar M. Cortés, Jorge Lorenzo-Trueba, Andre S. Rovai, Robert R. Twilley, Mark Chopping, Temilola Fatoyinbo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Although mangroves provide many beneficial ecosystem services, such as blue carbon storage and coastal protection, they are currently under threat due to changes in climate conditions, such as prolonged drought exposure. Under drought conditions, evaporation exceeds precipitation and high soil salinities can lead to stunted growth and die-back. To quantify this interplay, we developed a database for low-lying and uninhabited mangrove islands in the Caribbean under various evaporation and precipitation regimes. We extracted physical and biological information from each island using remote sensing techniques and coupled it with a process-based model. We used this database to develop a model that …

Heavy Metals In Rural Soils: A Case Study In Jennings County, Indiana, Madeline Hill

All-Inclusive List of Electronic Theses and Dissertations

Heavy metals, such as lead and mercury, can be toxic if exposure levels are too high. People are often concerned about lead exposure from water or paint, but soil is another potential exposure avenue for many metals. While some heavy metals, including mercury and lead, are found in emissions from coal-burning power plants and from incinerators, many metals accumulate in soils from past uses (ex. lead paint, leaded gasoline, chemical spills, industrial emissions, and natural occurrences). It is important to have soil tested to check metal concentrations because consumption or inhalation of these metals can lead to permanent damage and …

Iowa Waste Reduction Center Newsletter, December 2024, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Contents:

--- Meet Drew Miller
--- Farewell Kendall
--- IWRC Advisory Member Updates
--- Changes Coming to Online Painter Training
--- January Reporting Deadlines
--- IAEP: 30 Years of Supporting Iowa Small Businesses

The Relationship Between Salvinia Molesta Infestation And The Microbial Ecology Of Wetlands At Caddo Lake, Tx, Usa, Martin Hadsell

Electronic Theses and Dissertations

Wetlands are known to host many beneficial geochemical processes such as nutrient cycling and carbon sequestration. These processes are primarily driven by the microbial communities within a wetland. The establishment of non-native invasive species within wetlands has the potential to alter the once beneficial functionality of wetland microbial communities due to the sensitivity microbes have towards environmental changes. Because of this, several metagenomic studies have been conducted to assess microbial community response to aquatic plant invasion; however, there haven’t been any studies researching the influence of Salvinia molesta (D.S. Mitch.), commonly known as Giant Salvinia, on microbial communities. The goal …

Bioremediation Of Effluent Water In A Coal Ash Disposal Area: Optimizing Microbial Sulfate Reduction, Ryka Shea

Electronic Theses and Dissertations

Coal combustion residues (CCR) pose a serious environmental threat, even long after they are disposed of in specialized landfills, due to their complex composition and potential for leaching into waterways. This study focuses on the issue of elevated sulfate concentrations at the Martin Lake Steam Electric Station (MLSES) A-I Disposal Area in Panola County, Texas, where CCR are disposed of in a permanent landfill. Currently, this site is exceeding its regulatory limit of sulfate concentrations in its effluent and is in need of a cost-effective and sustainable solution to this problem. This research utilized benchtop experiments to investigate sulfate reducing …

Informing Management Of American Shad (Alosa Sapidissima) In The Carolinas: Evaluating Novel Fish Passage Approaches And Acoustic Tracking Methods, Margaret Gaither

All Theses

Acoustic telemetry is a valuable tool for fisheries scientists to study the movements and migratory behaviors of aquatic organisms. A critical assumption of this method is that tagged fish exhibit similar behaviors and survival rates as their untagged counterparts. To investigate this, we conducted a 12-week laboratory study on adult American Shad (Alosa sapidissima) using gastroesophageal insertion of acoustic transmitters. We implanted 80 fish with dummy transmitters and monitored tag retention and survival. Our analysis, employing a mixed effects Cox’s proportional hazards model, revealed no significant differences in survival between tagged and control fish, regardless of sex. Additionally, …

Effect Of Integrated Crop–Livestock Systems On Soil Properties And Microbial Diversity In Soybean Production, Namita Sinha, Brett R. Rushing, Aniruddha Acharya, Shankar Gaapathi Shanmugam

Faculty Publications - Biological Sciences

Integrated crop and livestock systems (ICLSs) have been considered an important management-based decision to improve soil health by carbon sequestration. A two-year study (2019–2021) at CPBES in Newton, MS, was conducted to evaluate the effect of an ICLS on soil microbial diversity in the southeastern region of the USA, representing agroclimatic conditions that are warm and humid. Amplicons targeting bacterial 16S rRNA genes and fungal ITS2 regions were sequenced. Taxonomic assignment and characterization of microbial diversity were performed using QIIME2®. Soil fungal diversity pattern showed significant difference (alpha diversity, p = 0.031 in 2020 and beta diversity, p = 0.037 …

Analyzing Food Sources And Food Insecurity Of Kichwa Farming Families In The Ecuadorian Amazon, Reina Watanabe

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

While the right to food is internationally recognized and the United Nations established the sustainable development goal to end hunger and achieve food security by 2030, many households remain without consistent access to food in 2024. In Latin America, approximately 4 in 10 households were reported as food insecure in 2020 with higher rates in rural and indigenous communities. Rural areas, which have great overlap with indigenous communities in Ecuador, experience disproportionately high levels of poverty and food insecurity compared to urban areas. The most populous indigenous nationality in the Ecuadorian Amazon and the participants of this study are the …

Recreational Fishing For Western Rock Lobster: Estimates Of Participation, Effort And Catch In 2023/24, Claire B. Smallwood, Karina L. Ryan, Alissa C. Tate

Fisheries Research Reports

The Western Rock Lobster (WRL) (Panulirus cygnus) is the most commonly caught Rock Lobster (RL) species in Western Australia. Catches from the commercial and recreational sectors are required to determine and monitor Total Allowable Commercial Catch (TACC), Total Allowable Recreational Catch (TARC) and the proportion of Allowable Harvest Level (AHL) achieved. The TARC is set at 5% of the AHL and evaluated in the harvest strategy based on a 5-year average.

Data for the recreational sector are obtained using phone-recall surveys to provide annual estimates of participation, fishing effort and retained catch (by numbers) from recreational fishers who hold a …

Investigating Nekton Response To Changing Salinities In The Mississippi Sound: An Experimental And Statistical Approach, Adam Murray

Master's Theses

The Mississippi Sound provides nursery habitats for many coastal species and is recognized for its commercial fisheries. Previous freshening events linked to the Bonnet Carré Spillway, a Mississippi River flood diversion structure, proved catastrophic for oyster populations in the Mississippi Sound, but effects on mobile fish and shellfish species are not well-defined. The planned Mid-Breton Sediment Diversion (MBSD), an initiative to combat wetland loss, is also forecasted to lower salinities in the region, increasing the need to better understand responses of commercially and ecologically important species to freshening events. The objective of this study was to characterize effects of salinity …

The Impact Of Wild Pigs (Sus Scrofa) On Avian Occupancy And Vegetation Structure, Kenneth Wilson

Graduate Theses and Dissertations

Invasive species, particularly wild pigs (Sus scrofa), pose a significant threat to native ecosystems through both direct and indirect impacts. Wild pigs are large-bodied omnivorous species that can consume a wide variety of plants and animals and are known for destructive foraging behaviors, which likely threatens avian communities through habitat alteration and can impact the long term structure of ecosystems where they are present.

In chapter 1, we used a combination of avian point count surveys, vegetation assessments, and camera trap surveillance to quantify how the occupancy of breeding birds in bottomland hardwood forests changed in relation to …

Quantifying Greenhouse Gas Exchange And Ecosystem Services In Ecosystems Managed For Nature-Based Solutions Using Eddy Covariance, Remote Sensing, And Models, Lucas Clay

All Dissertations

As global temperatures rise due to climate change, nature-based solutions are increasingly being used to restore nature and to remove carbon from the atmosphere. Nature-based solutions draw on methodologies such as ecological forestry and improved forest management to reduce emissions and maximize resilience. These protocols are still in their infancy and additional measurements and case studies are important to optimizing these protocols. Herein this dissertation we describe multiple measurement methodologies for both greenhouse gas (GHG) emissions and for ecosystem services. In coastal wetland ecosystems, the need for GHG measurements is paramount to understanding the ability of these ecosystems to reduce …

Performance Of Acoustic Telemetry And Space Use Of Pallid Sturgeon In The Lower Platte River, Nebraska, Christopher F. Pullano

School of Natural Resources: Dissertations, Theses, and Student Research

Pallid Sturgeon (Scaphirhynchus albus) are centenarian, potamodromous, rheophiles that historically occupied the Missouri River and Mississippi River basins. Listed on the U.S. Endangered Species Act in 1990, population declines are attributed to habitat fragmentation and degradation, as well as overharvest, and hybridization. A knowledge gap exists regarding the extent to which tributaries facilitate key life stages for Pallid Sturgeon. This study evaluated the capacity of acoustic telemetry to monitor the movements of Pallid Sturgeon in a shallow, braided tributary to the Missouri River. The specific objectives were to (1) evaluate the environmental variables influencing the performance of acoustic …

Occupancy Of Fish Species Of Greatest Conservation Need And Temporal Patterns Of Assemblage Occurrence In Sandhills Ecoregion, Nebraska Streams, Braxton M. Newkirk

School of Natural Resources: Dissertations, Theses, and Student Research

Fish species’ occurrence is influenced by environmental conditions across multiple spatial and temporal scales. Alteration to stream systems has the potential to affect occurrence patterns of fish species. Stream systems of the North American Great Plains face threats originating from climate change and anthropogenic activities resulting in negative implications for many fish species. The Sandhills Ecoregion, Nebraska is considered one of the largest intact grasslands in North America, and thus may experience fewer threats than surrounding areas. Stream systems of the Sandhills Ecoregion are home to 12 fish species of greatest conservation need (SGCN). Little context exists regarding the environmental …

Spatial Ecology Of American Bison On Vermejo Park Ranch, New Mexico, Kate Ann Asmus

School of Natural Resources: Dissertations, Theses, and Student Research

American bison (Bison bison) are a keystone species that impact grassland productivity, plant diversity, and landscape heterogeneity. We used GPS telemetry and a replicate herbivore grazing experiment on Vermejo Park Ranch in northeastern New Mexico to advance understanding of bison spatial ecology and grazing dynamics. First, we evaluated the potentially disparate influences of forage productivity and site fidelity on the size and selection of home ranges of bison. Home range size was strongly negatively influenced by forage productivity. However, home range selection was influenced more strongly by site fidelity than spatial variation in forage, as bison selected home …

The New Anthropocentrism: The Problem Of Water Conservation And Water Justice, Benjamin Stuart Milam

Open Access Theses & Dissertations

My objective with my thesis is to argue for and reinforce a type of anthropocentrism that is both environmentally conscious and consumable for an audience that is not necessarily well versed in philosophical literature. In the first chapter I go over philosophical frameworks, such as Anthropocentrism and Biocentrism, and why I believe they do not meet both of those criteria listed. After that I discuss New Anthropocentrism, coined by Clive Hamilton, and why I believe that a slightly modified version possesses qualities that I believe are needed for the crisis at hand. In chapter 2 I use that framework and …

Environmental Impact Assessments (Eia): Analysis Of Transboundary Environmental Impact Assessments For The Development Of A Uniform Teia Model, Nicolas Chapa

Open Access Theses & Dissertations

This dissertation investigates the evolution, processes, and importance of Environmental Impact Assessments (EIAs), focusing on transboundary EIAs and the need for a uniform framework. Originating from the National Environmental Policy Act (NEPA) of 1969 in the U.S., EIAs have become globally adopted instruments for assessing and mitigating environmental impacts of development projects. This work reiterates historical milestones, strengths, and current limitations of EIAs. Research also included a review of environmental regulations from Mexico, such as the General Law on Ecological Equilibrium and Environmental Protection (LGEEPA). Through several case studies requiring the use of transboundary EIAs, where shared resources and concerns …

Redefining Approaches For Measuring Landscape Subsidence And Permafrost Degradation In Arctic Tundra Environments, Tabatha Lynn Fuson

Open Access Theses & Dissertations

As climate change accelerates in the Arctic, the degradation of permafrost is leading to significant landscape transformation in tundra landscapes. This dissertation investigates the multifaceted responses of permafrost systems to warming, focusing on the dynamics of surface elevation changes and active layer thickness (ALT) across the North Slope of Alaska. In this study, I explore the capacity of repeat Terrestrial Laser Scanning (TLS) technology for modeling tundra features and detecting surface subsidence, specifically how different climate and landscape conditions during scanning impact TLS model precision. We also compare TLS model precision estimates to TLS model accuracy by comparing elevation values …

Understanding The Influence Of Traffic And Noise On The Wildlife Community Surrounding Fm106 And Sh100 In South Texas, Anna Rose Mehner

Theses and Dissertations

In South Texas, highways create landscape fragmentation, habitat degradation, and result in wildlife vehicle collisions. Vehicle collisions are the highest known cause of mortality of the endangered ocelot (Leopardus pardalis), which led Texas Department of Transportation to install nine wildlife crossing structures (WCS) on Farm-to-Market 106 and five on State Highway 100. These highways are along Laguna Atascosa National Wildlife Refuge, which is the location of the southernmost breeding population of ocelots in the United States. Many other wildlife species including bobcat (Lynx rufus) and coyote (Canis latrans), are present along these highways and …

Structure Modifications And Alternative Monitoring Designs Of Wildlife Road Mitigation Structures, Madison T. Nadler

Theses and Dissertations

Wildlife mitigation structures are designed to keep animals off roadways while providing them safe passage to the other side and not impeding traffic flow. Camera traps are commonly used to assess the success of these mitigation structures, but there are downfalls to both the methods and structures. Alternative mitigation structure designs are needed to better prevent wildlife from accessing roadways in areas where they should be deterred. Additionally, traditional camera trapping methods do not accurately capture the full wildlife communities that may be utilizing these structures and other survey methods are needed, specifically aimed at small mammals, amphibians, and reptiles. …

A Nursery Study Of The Interplay Between Soil Texture, Rooting Space, And Nurse Plants On Seedling Growth And Root Development In Woody Species Of Tamaulipan Thornscrub, Lance I. Santos

Theses and Dissertations

Reforestation attempts in semi-arid regions are plagued with seedling mortality. Blanket greenhouse practices may not be optimal, in addition, commensalism interactions between nurse plants are considered. To better understand the effects of soil texture and nurse plant interactions on growth and drought tolerance, two experiments were developed. For soil texture, Border palo verde seedlings were grown in different-sized plant bands with three soil types. To observe the effects of nurse plants, an experiment using guayacan, was developed using Texas Ebony, as a leguminous nurse plant. Plants were also exposed to a drought experiment. The results suggest that some soil textures …

Examining Hispanic Beginning Farmers And Ranchers In The Rio Grande Valley Through A Community Capitals Framework, Perla Kimberly Schrock

Theses and Dissertations

While existing literature addresses the experiences of beginning farmers and ranchers (BFR), there is a notable gap in research focused on Hispanic beginning farmers and ranchers (HBFR). This study aimed at exploring the unique experiences of HBFR in a predominantly Hispanic region, the Rio Grande Valley (RGV), employed the Community Capitals Framework (Flora et al., 2016). I conducted 16 semi-structured interviews with HBFR and local nonprofit organizations and federal employees, complemented by participant observations. Through thematic and content analysis of the interview transcripts, findings revealed valuable insights into the livelihoods of HBFR. Despite HBFR facing significant challenges, this study demonstrated …

Assessing Khumbu Region Glaciers Mass Balance Change Using Geospatial Techniques From 2012 To 2024, Yashvi Jagatbhai Shah

Electronic Theses, Projects, and Dissertations

The glaciers in the Hindu Kush Himalaya are critical for sustaining the water supply of South Asia's major rivers, upon which over 230 million people, both in the mountainous regions and lowland areas, depend. Climate change is driving rapid glaciers melt near the summit of Mount Everest, located at an elevation of approximately 7,906 meters (25,938 feet). This has resulted in glacier thinning occurring up to 80 times faster than the original ice formation. However, due to their disposition in a complex topographic setting and inaccessible terrain, continuous glacier observations pose significant challenges.

This study evaluated the mass balance of …

Phytoplankton Responses To Changing Irradiance And Carbon Fertilization, Alison Siersma

Graduate Theses and Dissertations (2019 - present)

Phytoplankton play a crucial role in marine ecosystems due to their innate ability to fix carbon. As atmospheric CO2 levels continue to rise from fossil fuel combustion, the resulting increase in dissolved CO2 and the concurrent decrease in ocean pH are likely to impact the phytoplankton community. The response of phytoplankton to elevated CO2 can vary significantly among species and environmental conditions (e.g. light, temperature, nutrient availability). To address these variations, an experiment was conducted using a controlled photobioreactor system, maintaining high and low light, constant temperature, nutrient levels, and two pCO2 concentrations. This study focused on two regionally relevant …

Time Series Decomposition Of Land Surface Temperature For Long-Term Trend Forecasting And Impact On Nesting Sea Turtle Habitats In The Arabian Gulf, Sachi Perera, Rommel H. Maneja, Mohamed Allali, Cyril Rakovski, Erik Linstead, Daniele Struppa, Ali Qasem, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Improving land surface temperature (LST) modeling is vital for mitigating climate change effects on various ecosystems and marine habitats such as important sea turtle habitats. Over the past decade, extreme temperatures have likely significantly affected nesting sea turtle habitats in the Arabian Gulf, with predominantly female hatchlings creating an imbalance in the sex ratio. Such shifts have profound implications for these habitats’ long-term survival and conservation management. This study leverages statistical machine learning models to measure ongoing temporal variations in LST. We break down the LST time series into trend, seasonal, and noise components using classical decomposition methods like X11, …