Life Sciences Commons^™

Competition And Herbivory Influence The Survival, Growth, And Physiology Of Native Tree Seedlings In The Kentucky Inner Bluegrass Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Terrestrial plant communities are shaped by competition for resources, herbivory, and abiotic processes. Savanna systems represent a dynamic coexistence of contrasting life forms (grasses and trees) shaped by competition and disturbance. The Kentucky Inner Bluegrass Savanna-Woodland (KIBSW) is described as an open woodland of shade intolerant species; however, climatic, and edaphic conditions can support closed-canopy forest. After European pioneer settlement (c1750-1800), over 99% of “savanna-woodlands” have been lost. KIBSW remnants are experiencing a recruitment failure, leading to a dominance shift in tree communities. I researched how tree-grass competition and mammalian herbivory influence KIBSW regeneration and maintenance. The KIBSW does not …

Sun Exposure And Protective Behaviors Among U.S. Hispanic Farmworkers, Claudia Marie Delgado Cebollero

Walden Dissertations and Doctoral Studies

Sun exposure increases the risk of sun-related illnesses and skin cancer among U.S. Hispanic farmworkers. Reinforced by the health belief model, the purpose of this study was to determine the association between socio-demographic factors (i.e., age, educational attainment, gender, income, and marital status) and skin cancer with the level of sun exposure (sun’s effect on skin, sunburn reported) and protective behaviors (use of cap/visor, use of sunscreen) among adult Hispanic farmworkers in the United States. The study included Hispanic farmworkers aged 21 or older (N = 112) who responded to the 2015 National Health Interview Survey. Ordinal logistic regression showed …

Dormant Propagules In Demographic Studies: A Recurrent Bias And Potential Solutions, Federico Borghesi

Graduate Thesis and Dissertation 2023-2024

In the face of unprecedented anthropogenic change, we increasingly turn to emergent technologies and extensive data sets for solutions that complement much needed systemic changes in our societies. These technological solutions, however, must be approached with care. We must recognize and address biases in the way data has been accumulated. In demographic studies, dormant life stages, such as seed banks, and other cryptic factors have often been neglected. The potential consequences of these omissions have been extensively described in the literature. In the first chapter, I analyze patterns of seed bank omissions in demographic models, finding unjustified omissions are widespread …

Investigation Of Small Mammal Species Richness, Abundance, And Genetic Population Structure On And Around The Eastern Washington University Prairie Restoration Site, Sarah Deshazer

EWU Masters Thesis Collection

Small mammals are an ecologically important component of every landscape on Earth. They are a food source for higher trophic level animals, disperse plant seed and mycorrhizal fungi spore, engineer the landscape through burrowing and foraging activities, and alter plant community composition through selective predation of seed and grain. Studies have shown that small mammals may help facilitate the transition between successive stages in prairie restoration. Eastern Washington University has dedicated 120 acres of campus land to restoration of native prairie habitat. Small mammals can play both a positive and a negative role in restoration, therefore it is important to …

Quantifying The Carbon Stored And Sequestered By The Trees On Pomona College’S Campus, Paola A. Giron-Carson

Scripps Senior Theses

We are experiencing a climate crisis that must be confronted with strategic mitigation. Pomona College contributes to the climate crisis through its emissions for which there is a baseline record. However there is no baseline record of the climate mitigation currently performed by the trees on Pomona’s campus through carbon storage. This study seeks to determine a current baseline quantity of carbon stored and sequestrated by Pomona’s trees as well as possible courses of climate mitigation for Pomona College to take. Initial information gathering was conducted through interviews with several stakeholders. This study was conducted using data collected prior to …

Treatment Plan And Educational Guide For Removing Invasive Barnyard Grass, Canada Thistle, And Cocklebur Within The Baduwa't (Mad River) Estuary, Ashley S. Turner, Alex D. Lallman

Cal Poly Humboldt Capstone Honor Roll

Our project is located at the Baduwa’t Estuary. We partnered with CalTrout to assist them with meeting one of the objectives for their Mad River (Baduwa’t) Estuary Floodplain Habitat and Public Access Enhancement Project. CalTrout partnered with the landowner, McKinleyville Community Services District, to restore 4.25 acres of the estuary. Our project focused on reducing the abundance of invasive plant species within the estuary area. The target plant species were barnyard grass, Canada thistle, and cocklebur. First, we conducted a literature review to learn the best management practices for eradicating the three target species. Then we conducted a field survey …

The Birds And The Trees: Quantifying The Drivers Of Whitebark Pine Decline And Clark's Nutcracker Habitat Use In Glacier National Park, Vladimir Kovalenko

Graduate Student Theses, Dissertations, & Professional Papers

Whitebark pine (Pinus albicaulis), recently listed as threatened under the Endangered Species Act, is in steep decline in Glacier National Park, Montana, USA due to the non-native pathogen Cronartium ribicola, causal agent of the fatal disease white pine blister rust. A sample of the park’s population suggests that approximately 70 percent of whitebark pines have died, while 65 percent of the remaining trees are infected. Using landscape and climate variables, we show how geographic location, elevation, aspect, solar radiation, relative humidity, and snowpack interact with tree diameter to affect mortality, disease incidence, cone production, and regeneration. We also examine how …

Evolutionary History And Adaptation To Salinity In American Alligators, John Konvalina

Electronic Theses and Dissertations, 2020-

Stressful environments can commonly be found at the edge of a species range and may be a driver for adaption in suboptimal environments. Furthermore, the edge of a species' range can expand and contract over time, resulting in multiple independent invasions of the same stressful habitat. Elucidating population genetic structure and demographic history can aid in determining the which geologic factors impact range distributions and when climatic changes occurred driving genetic patterns observed in contemporary populations. Moreover, populations at the edge of the species range may adapt to the stressful environments that occur at the range edge and exhibit genetic …

Seasonal Growth, Movement, And Survival Of Juvenile Coho Salmon (Oncorhynchus Kisutch) Utilizing Restored Rearing Habitat, Monica S. Tonty

Cal Poly Humboldt theses and projects

The Scott River supports the most robust population of threatened Coho Salmon Oncorhynchus kisutch remaining in the Klamath River basin. Even in the Scott River, low quality and restricted extent of juvenile rearing habitat limits the Coho Salmon population to a small fraction of historic abundance. To support persistence and recovery of Scott River Coho Salmon, the Scott River Watershed Council (SRWC) has constructed a portfolio of restoration projects to improve juvenile rearing habitat, including beaver dam analogs (BDAs). The Scott River BDAs were the first implemented anywhere in California. This study compares juvenile Coho Salmon responses associated with production …

Effects Of Climate Change And Landscape-Scale Forest Management On Avian Communities, Abundance, And Nest Success In The Appalachian Mountains, Hannah L. Clipp

Graduate Theses, Dissertations, and Problem Reports

Birds are integral components of ecosystems and account for billions of dollars in tangible benefits to humans. As such, recent continental declines of bird species have ecological and economic consequences, providing the impetus for my dissertation research. I identified knowledge gaps and proposed novel questions about how birds in the Appalachian Mountains are influenced by changing environmental conditions due to climate change and forest management. The Appalachian Mountains encompass an important biogeographical region with high conservation value due to its myriad habitats and corresponding bird species diversity. Thus, there is a critical need to evaluate the effects of shifting climate …

Application Of The Fine Sediment Biotic Index To Three Drain Tiled And Ditched Agricultural Systems In Southern Minnesota, Bailey Sanders

All Graduate Theses, Dissertations, and Other Capstone Projects

Artificial drainage is a common agricultural management technique in the United States used to remove excess water from poorly drained soils. Approximately 22.48 million hectares of crop land are drain-tiled in the United States, providing long-term economic benefits to farmers. However, artificial drainage increases sediment transport in agricultural watersheds, which can degrade aquatic systems, destroy habitats, and limit biological diversity. Biotic indices based on benthic macroinvertebrates are commonly used to assess surface water quality, but recent studies show potential in developing sediment biotic indices using benthic macroinvertebrates to estimate fine sediment in streams. The objective of this study was to …

How Akron Affects The Water Quality Of The Cuyahoga River, Allyson Darst

Williams Honors College, Honors Research Projects

The purpose of this study was to analyze whether the city of Akron had negative effects on the Cuyahoga river, and determine if the Cuyahoga River was naturally able to remediate these effects downstream. The pollutants measured in this study include hardness, bromine, residual chlorine, iron, copper, lead, nitrate, nitrite, ammonium chloride, total chlorine, fluoride, carbonate, pH, total alkalinity and cyanuric acid. This study was done using water testing strips (JNW Direct) to test the water at four different locations along the Cuyahoga River downstream (North) of Akron. This study found that the city of Akron does have a negative …

Exploring Beaver-Facilitated Restoration In Grassland Channelized Streams, Jessica L. Sikora

Graduate Research Theses & Dissertations

Freshwater streams provide vital ecosystem services, but their ecological function is gravely impacted by agricultural practices especially in grassland ecosystems. Though there is evidence that the re-introduction of beavers can help restore the ecological function of streams, little is known about their restorative impacts in grasslands. At Nachusa Grasslands Preserve in Franklin Grove, IL, we investigated the presence and impact of beaver dams on their waterways. With increasing beaver dam volume, we found an increase in sediment retention and less sediment retention with increasing beaver dams upstream from a dam. Though we did not find evidence that beaver dam volume …

From Field To Shore: Policy Improvements To Better Protect Ecosystem And Human Health From Poultry Wastes In Virginia, Rachael A. King

Dissertations, Theses, and Masters Projects

Commercial poultry production is a large industry with economic importance in Virginia. However, mismanagement of manures and wastes generated from the poultry industry can be a serious threat to ecosystem and human health. Primarily, there is a concern about nutrient pollution related to runoff and infiltration of poultry wastes. High nutrient loading can cause groundwater contamination, eutrophication, and harmful algal blooms (HABs). Additional concerns include metals, antibiotics, and pesticides that can be found in poultry wastes. To determine existing threats to ecosystem and human health from the poultry industry, Virginia policies regulating the industry are reviewed and their strengths and …

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 …

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 …

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. …

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 …

Changes And Relationships Of Soil Aluminum, Organic Matter, And Hydrogen Ion Concentration With Rye Cover Crop, Arron Wilder

Cal Poly Humboldt theses and projects

Soil acidity is a common agricultural problem worldwide, as approximately 50% of all potentially arable soils are affected by pH limitations. At soil pH 3+) is considered to be the chemical form of aluminum in acid soil that hinders plant growth the most. Potentially, soil organic matter (SOM) can ameliorate the toxic effects of Al³⁺ on plants and microbes by binding with Al³⁺, thus preventing Al³⁺ (and other species of aluminum) from interacting in the rhizosphere. Increasing SOM also increases soil health indicators (i.e., microbial activity, soil water holding capacity, aggregate stability, porosity, etc.) while the …

Carnivore And Ungulate Occurrence In A Fire-Prone Region, Sara J. Moriarty-Graves

Cal Poly Humboldt theses and projects

Increasing fire size and severity in the western United States causes changes to ecosystems, species’ habitat use, and interspecific interactions. Wide-ranging carnivore and ungulate mammalian species and their interactions may be influenced by an increase in fire activity in northern California. Depending on the fire characteristics, ungulates may benefit from burned habitat due to an increase in forage availability, while carnivore species may be differentially impacted, but ultimately driven by bottom-up processes from a shift in prey availability. I used a three-step approach to estimate the single-species occupancy of four large mammal species: mountain lion (Puma concolor), coyote …

Tracing Atlantic Sea Scallops Using Radio Frequency Identification (Rfid) Technology, Will Shoup

Dissertations, Theses, and Masters Projects

Traceable seafood can be linked back to its origin and method of catch. Improving the traceability of marine organisms involves establishing a transparent Chain of Custody (CoC) by collecting data at checkpoints throughout the supply chain, from ship to shore to store. This report explores the feasibility of integrating Radio Frequency Identification (RFID) technology into the United States Atlantic sea scallop (Placopecten magellanicus) fishery in order to improve traceability. This report serves as a forward-looking evaluation of RFID technology that is intended to inform interested stakeholders of its functionality and capabilities. It is not intended to serve as a management …

Forest Management In The Context Of Global Change: Impacts Of Disturbance, Adaptive Management, And Invasive Species On Northeastern Forests, Jennifer Santoro

Graduate College Dissertations and Theses

Climate change is predicted to have variable and uncertain effects on forested ecosystems globally. In the northeastern US, natural disturbances have historically been a central driver of forest successional dynamics, but as climate warming is projected to alter the frequency and severity of these events, post-disturbance management strategies to sustain biodiversity and ecosystem services must adaptively change to promote forest resilience. A suite of adaptive silvicultural actions has been proposed to promote forest resilience in the face of uncertainty, but due to the multi-decadal scale of forest management, initial field experiments are only beginning to show results. To address these …

Winter Dynamics Of Storm Water Management Ponds And Winter Tolerance In Three Aquatic Plant Species, Patrick Strzalkowski

Theses and Dissertations (Comprehensive)

The vast majority of the research into the performance of stormwater management ponds (SWMPs) has been performed in warm regions or during the warmer seasons in temperate regions. It is presumed that SWMPs are inactive in the winter as any potential stormwater is trapped in snow and ice. The main goal of this thesis was to test this presumption and to study the dynamics and performance of three SWMPs during the winter. Remote water level loggers were installed into the three SWMPs and daily grab samples from the influents and effluents were taken and analyzed for total phosphorus (TP), chloride, …

Development Of A Framework To Support Community-Scale Nutrient Recovery For Local Crop Fertilization And Production, Scott A. Lopez

Graduate Theses, Dissertations, and Problem Reports

Nutrient and resource recovery (NRR) has become increasingly crucial as regions face deteriorating sanitation infrastructures, limited support, and growing environmental challenges. Implementing region-specific NRR technologies and systems could provide effective circular economy insights into addressing these challenges. Because of the multidisciplinary challenges associated with the design and implementation of NRR strategies, various government and local decision-makers need to collaborate effectively in the decision-making process. Structured decision-making (SDM) methodologies are practical when determining the most appropriate NRR strategy for nutrient-rich waste streams. However, applications of computational SDM limited because of the vast amounts of data that are needed to analyze the …

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 …

Macrolichen Inventory Of The Horse Mountain Botanical Area, Six Rivers National Forest, California, Usa, Sarah Norvell Conway

Cal Poly Humboldt theses and projects

Macrolichen diversity and community composition was determined for an area of high botanical interest in the Coast Ranges of Northern California – the Horse Mountain Botanical Area (HMBA) in Six Rivers National Forest. The Coast Ranges have been suggested to have high epiphytic macrolichen diversity, yet detailed site-specific macrolichen surveys are lacking for the area. Here we present comprehensive data on macrolichens of the HMBA integrated with environmental metadata at the landscape level. Twenty 0.4 ha sampling plots were positioned across the varying habitats of the HMBA and macrolichens were intensively sampled from all substrata. Out of 888 total collections, …

Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer

Cal Poly Humboldt theses and projects

A growing interest in sustainable waste management and the implementation of new policies have prompted a shift towards alternative resource recovery methods for organic waste, including food waste. To effectively assess alternative food waste treatment scenarios, it is important to evaluate the life cycle impacts associated with each scenario. The storage phase of food waste, encompassing its accumulation in kitchens, and storage in bins for collection and transportation, has been overlooked as a source of greenhouse gases in previous studies. This investigation aimed to identify the greenhouse gases emitted during the initial five-day period of low-oxygen storage. An open dynamic …

Socio-Ecological Economic Impact Analysis Of Food Systems Initiatives Using Mixed Methods And Community-Based Research Approaches, Josiah J. Taylor

Graduate College Dissertations and Theses

Many NGO and government community development programs seek to alleviate complex problems related to food systems and agriculture. Yet, without integrated social, ecological, and economic impact analysis we cannot understand or communicate the value of such interventions. For this research, we partnered with food and agriculture organizations using participatory action research approaches to co-develop and test tools for holistic program analysis. We then used these tools to conduct and co-produce a holistic analysis and evaluation of program impacts. The first chapter provides background and context for the body of the dissertation. Chapter two details work with Hunger Free Vermont to …

Groundwater Governance And Agricultural Sustainability: Examining Farmer Interactions With California’S Sustainable Groundwater Management Act, Zachary Matthew Goldstein

Graduate College Dissertations and Theses

Climate change has exacerbated groundwater depletion globally, and policymakers have struggled to effectively manage groundwater resources. California enacted the Sustainable Groundwater Management Act (SGMA) in 2014 to restore groundwater to sustainable levels.

The first paper of this thesis examines the drivers associated with uptake of groundwater conservation practices in agriculture. While a rich body of research has explored farmers’ conservation practice adoption, understanding of groundwater conservation practices is more limited. This study explores how information sources influence the actual and intended adoption of groundwater management practices in California. Using survey data from farmers (n = 553) in three largely agricultural …

Paleolimnological Data Synthesis To Assess Long-Term Ecological Change In Vermont Lakes, Ismar Biberovic

Graduate College Dissertations and Theses

Lakes are excellent early indicators of environmental change on a landscape scale. Due to their connectedness in the landscape, any alteration of land-cover extends beyond a single watershed and can only be amplified by the effects of climate change. These processes can reflect differently across lakes of various characteristics, however, combined, they can leave a lasting impact on biogeochemical processes of a lake, resulting in profound effects on biological communities residing in it. Lake sediments are terrific archives that integrate and preserve this evidence, which then allows us to investigate the extent to which a lake has changed given its …