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The Characterization Of Riparian Vegetation In Agriculture Drains Impacted By Phragmites Australis And Drain Management: A Southwestern Ontario, Canada Case Study, Ryan Mackenzie Graham

Electronic Theses and Dissertations

Agricultural drainage systems are important components of regional ecosystems and play key roles in ecosystem functioning. Biodiversity is a service provided by drains which is not fully understood in agriculturally dominated areas and is disrupted consistently by drain management, specifically in drains invaded by Phragmites australis. The objective of this thesis was to characterize the contribution of regional vegetational biodiversity provided by drainage systems, across sites representing a gradient of management frequencies. Drains were separated into management categories: Low (managed +5 years ago), Medium (managed every 3-5 years), or High (managed yearly). Plant abundance was measured and biodiversity indices …

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 …

Quantitative Change Analysis Of Undisturbed Lands In Eastern South Dakota: 2012-2021, Riley W. Wollschlager

Electronic Theses and Dissertations

The actual rate of loss of undisturbed prairie and woodland in eastern South Dakota is unknown, and the landscape composition of the region continues to change. Undisturbed land is land with no proven prior cropping or other disturbance history. Agriculture, development, recreation, and other land use practices create disturbances resulting in the further conversion of undisturbed prairies and woodlands. Previous work by South Dakota State University (SDSU) quantified the remaining undisturbed land in eastern South Dakota as of 2012 (Bauman et al 2016). Farm Service Agency (FSA) common land unit (CLU) and National Agricultural Imagery Program (NAIP) imagery were the …

Walleye Feeding, Movements, And Energetics Reveal The Importance Of Connected Wetlands In Glacial Lakes, Logan M. Cutler

Electronic Theses and Dissertations

Fish require a variety of resources including prey, thermal refugia, and different physical habitat characteristics to grow and reproduce. All necessary resources are rarely provided by a single habitat, resulting in tradeoffs between occupying different habitats; therefore, the ability to move among heterogenous habitats is critical. These tradeoffs may occur in lakes with connected wetlands where the main lake habitats tend to be more thermally stable, but wetlands often provide more diverse and abundant prey. For my second chapter, I compared prey diversity and abundance as well as Walleye (Sander vitreus) diets and condition in a large glacial lake (Lake …

Using Machine Learning Classification And Esa Sentinel 2 Multispectral Imager Data To Delineate Marsh Vegetation And Measure Ecotone Movement In Coastal Georgia, Thomas A. Pudil

Electronic Theses and Dissertations

Tidal marshes are unique communities that are subjected to environmental stressors including sea level rise, salinity change, and drought, resulting in constant change. It is important to monitor these changing areas because of the ecosystem services they provide to us, such as protection from storms and carbon sequestration. The proposed work for this thesis project is focused on the study of tidal marshes and the dynamics between the vegetation species within them. The aim of this project is to use geospatial technology and analyses, along with machine learning classification methods, to monitor change in these valuable ecosystems. The Georgia coast …

Middle Savannah River: An A/R/Tographic Ecopedagogical Ethnography Experimenting With Rhizomatic Perspectives, Lisa Augustine-Chizmar

Electronic Theses and Dissertations

This research is an experiment in perspective. Using the four commonplaces (Schwab, 1978), I practiced letting the Savannah River teach me what there is to know about the water, the land, the people, and the other entities that depend on ki through artistic, ethnographic, and ecopedagogical lenses. The ethnographic findings describe the social actors that depend on ki and give a voice to the River. The a/r/tographic findings display the River on a canvas map through two hundred years using paint, clay, photography, video, abstract acrylics, and fabric. Together, these methods contribute to a unique ecopedagogical journey. This word cloud …

Developing Best Practices For The Propagation Of Spartina Alterniflora For Use In Salt Marsh Restortaion, Justin Hinson

Electronic Theses and Dissertations

Coastal salt marshes are valuable ecosystems under threat from climate change and sea level rise. Living shorelines offer a promising solution, often incorporating the foundational salt marsh species Spartina alterniflora due to its ability to tolerate natural stressors and maintain sediment stability. However, research suggests that seed-based propagation protocols should be developed on a local scale due to the genetic heterogeneity within and between S. alterniflora populations. Here, we attempt to contribute to the development of one such protocol for coastal Georgia S. alterniflora.

In Fall 2021, seeds were collected bi-monthly from four marshes of varying ocean proximity and …

Remote Sensing Of Georgia Tidal Marsh Habitats Using Aerial Photography And Planetscope Satellite Imagery, Harrison M. Currin

Electronic Theses and Dissertations

Globally, tidal marshes cover about 90,800 km. Within the state of Georgia tidal marshes are primarily located behind the barrier islands and total 1,619 km². The combination of high salinity environments and daily inundation, and being dependent on river output, make these dynamic systems. Tidal marshes provide numerous ecosystem services such as carbon and nitrogen sequestration, flood control, coastal protection, and numerous biogeochemical processes. Due to their unique position, tidal marshes are under threat from sea level rise, drought, coastal development, and large-scale disturbance events. Tidal freshwater marshes are especially susceptible to these threats due to their geographic …

Water Literacy In Drought-Prone Regions: Case Studies From Aurora, Colorado, Usa And Cape Town, Western Cape, South Africa, Meghan Mccarroll

Electronic Theses and Dissertations

Water managers around the world must reevaluate their approach to water security as challenges continue to grow. Supply-focused paradigms that aimed to capture, control, and commodify water resources are increasingly unreliable and often depend on environmentally and socially damaging practices. Of particular concern are regions experiencing climate shocks and aridification from rising global temperatures. In order to stretch limited water resources using equitable water policies, conservation programs, and alternative water sourcing, water managers must invest in a water literate citizenry. Water literacy is the culmination of water-related knowledge, attitudes, and behaviors. The benefits of a water literate citizenry abound, including …

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. …

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 …

Sediment Microbial Community Diversity And Function In Response To Legacy And Prevailing Pollutants In Southern Ontario Watersheds, Nicolas Falk

Electronic Theses and Dissertations

Managing and mitigating point and non-point contamination to freshwater resources depends on reliable and sensitive monitoring of ecosystem health. Microorganisms in surface waters and sediments respond rapidly to anthropogenic disturbances, making them valuable bioindicators of human-induced landscape change. However, there lacks a baseline understanding of microbial community composition and function in industrially and agriculturally impacted regions of the Great Lakes. Without a reference state of microbial diversity and activity, future investigations seeking to integrate microorganisms into ecosystem assessments will lack context. Using genomic tools and measurements of chemical and nutrient contaminants, this thesis provides case studies of microbial community responses …

Dynamic Distributed Energy Resources For Expansion Of Ontario’S Greenhouse Sector, Lysandra Naom

Electronic Theses and Dissertations

The vegetable greenhouse sector is rapidly growing and adopting technology advances like supplemental lighting. Supplemental lighting has a dynamic impact on the demand and consumption of a greenhouse’s electricity load. There is uncertainty on the rate of adaptation of technologies and the impact this could have on the power consumption of the sector. Without electricity availability, the sectors innovation and expansion can come to a halt. This research focused on investigating greenhouse electrical load models and lighting trends to forecast demand on electricity grids and discover potential for Distributed Energy Resource (DER) applications.

This thesis presents a series of studies …

Cytotoxicity And Reproductive Impairment In Rainbow Trout Cell Lines Exposed To Microcystis Aeruginosa Extracellular Metabolites, Keira Harshaw

Electronic Theses and Dissertations

Current trends in cyanobacterial harmful algal blooms (cHABs) demonstrate increasing risks to human health and the health of aquatic ecosystems around the globe. Expansion of algal blooms, both geographically and temporally, serve to place increasing numbers of freshwater species, including fish, in peril. Microcystis aeruginosa, one of the most common species of bloom-causing cyanobacteria, is capable of producing a vast diversity of biologically active compounds, however Microcystis studies are often dominated by microcystins. How non-microcystin metabolites contribute to Microcystis toxicity, particularly in freshwater fish, has been the subject of a limited, but growing, body of research. To contribute to …

Consequences Of Environmental Manipulation On Behavioural And Neuromorphological Plasticity As It Relates To The Reintroduction Of Atlantic Salmon (Salmo Salar) To Lake Ontario, Ali I. Mokdad

Electronic Theses and Dissertations

The reintroduction of imperilled species has become an important tool in conservation biology and relies on the captive-rearing of remaining individuals, or a subset thereof, as a lifeline to prevent extinction. The success of reintroduction efforts has generally been low, mainly due to poor post-release performance of captive-reared animals. Captive-breeding programs tend to produce behaviourally and neurologically compromised animals that deviate from wild phenotypes and are less fit in natural settings. While genetic adaptation can account for some of the behavioural deficiencies expressed by captive-reared animals, phenotypic plasticity has been shown to play a large role. Phenotypic plasticity is generally …