Digital Commons Network^™

Evaluating Abiotic And Biotic Factors Affecting Plant Succession Processes At Malheur Lake, Beth Boos, Sammy L. King

LSU Master's Theses

Arid wetlands are diverse systems that provide habitat for a variety of flora and fauna, including stopover and breeding habitat for migratory birds. In the western United States, these wetlands support a network of stopover sites on the Pacific Flyway, and due primarily to wetland loss and alterations, these areas are becoming more isolated. Malheur Lake is a shallow endorheic lake in eastern Oregon that supported a robust emergent marsh throughout most of the 20^th century. However, following large scale flooding in the 1980s, emergent vegetation was extirpated and has only reestablished in small patches. Our objective was to …

A Camera Trap Study Of Scavenger Species On The University Of Mississippi Campus, Lise Larsen

Honors Theses

This is a camera trap study to understand what kind of mammalian scavenger community we have on the University of Mississippi campus and where they are most prominent. Three motion-triggered cameras were used to survey ten buildings on campus over ten weeks. A low number of individuals were caught on camera during this study. There were limitations on this study such as a low number of cameras and a short span of time. More research needs to be done to understand the scavenger community on this campus.

Eco-Interoception: What Plants, Fungi And Protista Have Taught My Body, Sara Riley Dotterer

Art Theses and Dissertations

To me, ecology is the relational, full-body awareness that I am made up of and deeply connected to everything around me; and for better or worse, this is reciprocal. I form ecotones, an ecological transitional zone between two ecosystems, with the world around me. I use this ecotonal lens to blur binaries and dissolve boundaries between me and the world “outside my body.” During my Masters of Fine Arts at Southern Methodist University, I have continuously explored and represented the lives of various more-than-human species outside of my body, including plants, fungi and protista through an ecotonal lens. Although these …

Compatibility Between Native Mississippi Ectomycorrhizal Fungi And Native And Exotic Pine Hosts: Testing For Specificity And The Potential For Rapid Evolution, Hailey A. Long

Honors Theses

Pines are highly invasive trees that are commonly used in pine plantations throughout the Southern Hemisphere. However, the survival and subsequent invasion of pines in exotic environments are dependent on the obligate symbiosis between ectomycorrhizal (ECM) fungi and pines. ECM fungi vary in host specificity and compatibility from pine-specialist species in the genus Suillus to broad generalists, such as species within the genera Pisolithus and Scleroderma. In Experiment 1, we sought to understand how the geographic origin of ECM fungi native to the southeastern United States and two pine species (native southeastern United States Pinus taeda and exotic Pinus …

Density And Nest Success Of Shrub-Dependent Birds On Formerly Strip-Mined Lands, Luke Headings

Electronic Theses & Dissertations

As bird populations continue to decline across North America, it is important to understand the benefits that disturbed habitats can have for breeding birds. One of the major land disturbances and causes of habitat loss in the United States is surface mining, which often results in altered vegetative communities. The primary goal of this study was to evaluate the relationships between bird populations, habitat, previous and current land use, and densities of invasive plant species on formerly strip-mined land. Due to the proliferation of invasive shrub species in post-mined landscapes, we sought to determine the effects of post-mined habitat features …

Mowing Cattail Cover To Increase Aquatic Vegetation Diversity On The Coeur D’Alene River Floodplain In Cataldo, Idaho, Makenna J. Tabino

2023 Symposium

The Schlepp Easement is a 400 acre wetland on the Coeur D’Alene River floodplain, near Cataldo, Idaho. The wetland has been restored to protect it from heavy metal pollution transported downstream from mining sites near Kellogg, Idaho, the location of the Bunker Hill EPA Superfund Site. This wetland was restored to provide safe habitats and feeding grounds for migratory waterfowl and to maintain wetland biodiversity. However, cattail is prone to becoming overdominant and outcompeting other plants, which greatly limits a wetland’s biodiversity. Our objectives were to test whether aquatic boat mowing can reduce cattail cover, improving species diversity and cover …

Determining The Impact Of Post-Harvest Water Management On Chironomid Abundance, Agrochemical Biomass And Potential Trophic Biomagnification, Mason Thomas

Theses and Dissertations

Agriculture has diminished shorebirds’ natural habitat in the Mississippi Alluvial Valley. Remaining natural stopover sites are supplemented with agricultural fields during the fall and winter. This study evaluates the impact of 4 different post-harvest water management strategies on shorebird food abundance and potential agrochemical biomagnification. Chironomid samples estimated abundance, biomass, and chironomid agrochemical concentration in each field. A risk assessment of agrochemical biomagnification to shorebirds was made across all treatments. Of treatments represented on all study sites, winter treatment had greatest chironomid abundance and biomass. Models indicated that days since flood initiation, start date, and temperature are significant predictors of …

Evaluation Of Nutrient Digestibility Of Weaned Calves From Early And Late Shedding Dams, Jennifer Keele

Theses and Dissertations

Researchers have investigated several factors that could alter fetal growth, including nutrient restriction (Valiente et al., 2021), hair shedding (Gray et al., 2011), and extreme hot and cold temperatures (Davidson et al., 2022). Hot temperatures and increased humidity percentages in the southeast United States caused researchers to investigate the hair coats of Angus cattle in the commercial production setting. An improvement in fiber digestibility and calf birth and weaning weights has been observed in Angus dams that shed 50% of the winter hair coat by May (Gray et al., 2011; Burnett et al., 2021). Our objective of this experiment was …

Analysis Of Gene Evolution In The Long-Lived Heliconius Butterfly Genus, Leann Ward

Theses and Dissertations

The butterfly genus Heliconius has an unusually long lifespan (six to eight months compared to only several weeks) and the unique ability to feed on pollen. The additional amino acids provided by a pollen diet seem intrinsically tied to longer lifespan in Heliconius. Because of these traits, Heliconius may be a valuable model species for future aging studies. As a preliminary analysis, we investigated differences in gene evolution between Heliconius and seven short-lived butterflies. We observed that the Heliconius genes had significant differences in evolutionary rates, in the direction of selection, and in the amounts of site-specific positive selection compared …

Macroecological Patterns Of Frugivorous Fishes’ Diversity (Serrasalmidae) In The Amazon Drainage Basin, Karold Vivianna Coronado Franco

Theses and Dissertations

The Amazon River drainage basin is known as the most biodiverse region in the world. Regarding freshwater fish, this region contains around 15% of the world's fish richness. The fish family Serrasalmidae have a variety of feeding preferences including Pacus (herbivores) and Piranhas (carnivores). Fruit eating fish species are evolutionarily the oldest species in the family and have a mutualistic interaction with flooded forests. Considering the diversity of feeding habits of the Serrasalmidae family, it represents an excellent model to study ecological questions related to factors that influence the spatial distribution of species and factors that contribute to the maintenance …

The Response Of An Avian Community To Intercropping And Forest Management Practices In A Private Working Pine Forest, Rebecca Doyne Bracken

Theses and Dissertations

Within managed pine forest systems, a plethora of bird species exist throughout the lifecycle of a stand akin to what may be experienced through post-disturbance regeneration in a natural forest system. I sought to address how breeding avian communities shift across time in response to stand aging and forest management, evaluate species-specific responses to stand conditions, investigate the responses of at-risk avian species to forest management, and determine avian non-breeding, over-wintering presence in a managed loblolly pine (Pinus taeda) forest. I conducted breeding bird point count and vegetation surveys within five stands of privately owned and managed pine forest in …

Mechanistic Examination Of Protist-Mediated Plant Growth Through The Comparative Development Of Medicago Truncatula, Shane Connolly

University Scholar Projects

Protists are known to increase plant growth through two main mechanisms: the microbial loop and the alteration of the root microbiome. The microbial loop is a nutrient recycling method in which protists provide inorganic nitrogen ions to the plant. Alteration of root microbiome leads to the removal of plant pathogens and shifting communities towards plant growth-promoting bacteria (PGPB). This study aimed to elicit which mechanism could produce the largest boost in shoot weight for Medicago truncatula. A series of microcosm experiments were explored in which M. truncatula was grown with variable microbiome structures to allow for mechanism differentiation. The …

Synecological Response Of Spring Benthic Prokaryotes And Macroinvertebrates To Paleozoic Roof Pendant-Derived Calcium, Ariel D. Friel, Khaled Pordel, Zachary Meyers, Cale O. Seymour, Nicole J. Thomas, Fred M. Philips, Jeffrey R. Knott, Donald W. Sada, Laura Rademacher, Marty Frisbee, Brian P. Hedlund

Life Sciences Faculty Research

Despite the ecological significance of desert springs, little is known about relationships between spring hydrogeochemistry and ecology, particularly over multiple trophic levels. Here, we surveyed microbial communities (bacteria and archaea) and benthic macroinvertebrate (BMI) communities in springs that recharge through granitoid bedrock in Owens Valley, CA, to determine whether subtle geochemical differences imparted by metamorphosed roof pendant weathering in the source area affect spring ecosystems. Relative to other springs, roof-pendant-recharged springs were characterized by elevated (1) Ca2+/Na+, Ca2+/Mg2+, and divalent/monovalent cation ratios, (2) relative abundance of taxa inferred to be benthic aerobes and prosthecate/stalked bacteria, and (3) abundance and diversity …

Coloration Of Western Alaskan Lakes From Spectral Data Correlates With Environmental Factors, Annemarie Timling

Undergraduate University Honors Capstones

The Yukon Kuskokwim Delta region of Alaska consists of over 100,000 small lakes; it is one of the largest lake-dense regions of Alaska. These small lakes are critical aquatic ecosystems that provide habitats for wildlife and play an important role in carbon and nutrient cycling. Lakes in the Yukon Kuskokwim Delta have a wide range of visible and near-infrared satellite spectra, which can vary over small spatial scales. These spectral differences may provide insight into the environmental properties of these small shallow lakes. Therefore, we want to investigate the relationship between the spectral data and environmental differences in these lakes. …

Locomotion And Life History In A Leaping Primate: Mechanics And Energetics Of Movement Throughout The Propithecus Lifespan, Nicholas Heslep

Masters Theses, 2020-current

Arboreal primates are typically altricial, exhibit long juvenile periods, and use dynamic locomotor behaviors that can be challenging and risky. Sifaka (Propithecus verreauxi) have particularly slow life histories for their size, with long juvenile periods, protracted reproductive careers, and long life spans. Slow somatic growth poses potential mechanical challenges for juvenile sifaka who use thigh-powered vertical clinging and leaping to follow group members during travel. I examined mechanical and energetic costs of movement in developing sifaka. I instrumented 8 wild sifaka (3 yearlings, 3 subadults, 2 adults) in 4 social groups with inertial sensors measuring tri-axial acceleration for …

The Response Of Microcystis And The Microbiome To Exogenous Hydrogen Peroxide, Bryan A. Puma

Masters Theses, 2020-current

Microcystis spp. produce prolific annual blooms in freshwater systems worldwide. The success of these blooms depends heavily on the Microcystis spp. overcoming environmental factors such as oxidative stress caused by reactive oxygen species (ROS) like hydrogen peroxide. Most Microcystis genomes do not contain many genes for responding to oxidative stress, including those that encode the enzyme catalase. Other cyanobacteria such as Prochlorococcus that also lack hydrogen peroxide degrading enzymes have been shown to benefit from partnerships with heterotrophic bacteria. Microcystis spp. may also receive similar benefits from heterotrophic bacteria in the phycosphere. To test this hypothesis, we examined the …

Understanding Context Dependent Responses To Climate Change In Arizona Tiger Salamanders (Ambystoma Mavortium Nebulosum), Kentrell Richardson

Masters Theses, 2020-current

Future emissions scenarios project climate change to increase average global temperatures by at least two ℃ in the next 50 years resulting in changes in local climate and causing increased variability within microclimates. Ectotherms are especially sensitive to climate change due to their dependence on environmental temperatures to regulate physiological functions. Changes in temperature are likely to impact thermally cued processes within amphibians and result in changes in variable magnitudes and directions within local populations.

Salamanders were placed in cups and partially submerged in a water bath and heated at a rate of ~0.27℃/ minute. Once salamanders were unable to …

Effects Of Litter Biomass And Soil Stoichiometry On Leaf Litter Amphibian And Reptile Density, Biomass, And Community Structure In Tropical Wet Forests, Alondra Medina Charriez

Masters Theses, 2020-current

Understanding the mechanisms behind patterns of diversity and abundance is a major goal of ecology. Research on nutrient stoichiometry has revolutionized the way ecologists understand the patchy distribution of mega-diverse invertebrate taxa that live at the soil surface and leaf litter in tropical wet forests. In this study, I studied the importance of soil nutrient concentrations and stoichiometry, habitat structure, and invertebrate biomass for patterns of amphibian and reptile density, biomass and community structure in two lowland wet tropical forests. I used data from study sites in Los Amigos Biological Station in Peru and two sampling occasions at La Selva …

Pasturelands As Natural Climate Solutions: A Socioecological Study Of Tree Carbon And Beef Production Trade-Offs, Bela Starinchak

Masters Theses, 2020-current

Forest restoration is the most effective natural climate solution, with the potential to sequester 37% of the carbon dioxide (CO₂) needed to reach the Paris climate mitigation goal. Cattle pastures offer an underutilized opportunity to increase global forest restoration efforts, improve biodiversity, and maximize carbon storage through the adoption of management strategies that prioritize the incorporation of trees into pasturelands. However, remote estimations of tree carbon storage in pastoral systems have never been field-verified and their accuracy is unclear. Furthermore, the effect of increased trees on cattle production is understudied across biomes. Lastly, the restoration potential of these …

Causes And Consequences Of Lasr Mutant Selection In Pseudomonas Aeruginosa Populations, Dallas L. Mould

Dartmouth College Ph.D Dissertations

Change is the only constant in life, and these changes, though random in nature, can have consequences. Quorum sensing is heterogeneous in phenotype and prone to negative selection. In P. aeruginosa, the regulator LasR is frequently non-functional in phylogenetically diverse isolates. Through repeated experimental evolution and mathematical modeling, we show that differences in growth enable lasR mutant evolutionary success and this requires a system enabling metabolic choices, known as carbon catabolite repression (or catabolite repression). The differences in catabolite repression between wild type and lasR mutants enable altered metabolite preferences, and the resulting differences in metabolic states enable intraspecies …

Aspects Of Distribution, Abundance, Habitat, And Life History Of The Caddo Madtom (Noturus Taylori), A Narrow Endemic Of The Ouachita Highlands, Brittany L. Mccall, Brook L. Fluker

Southeastern Fishes Council Proceedings

The Caddo Madtom, Noturus taylori, is a small catfish endemic to the Ouachita Mountain ecoregion in Arkansas, with habitat altered by land use practices and reservoir dams. We examined aspects of distribution, abundance, habitat, and life history of N. taylori during seasonal sampling from winter 2016 through fall 2017. Our sampling data were concordant with previous studies that suggested N. taylori is more widespread and has higher catch per unit effort in the Caddo River drainage when compared to the upper Ouachita River drainage. We did not detect N. taylori in the Little Missouri River drainage, where it is …

Du Undergraduate Showcase: Research, Scholarship, And Creative Works, Caitlyn Aldersea, Justin Bravo, Sam Allen, Anna Block, Connor Block, Emma Buechler, Maria De Los Angeles Bustillos, Arianna Carlson, William Christensen, Olivia Kachulis, Noah Craver, Kate Dillon, Muskan Fatima, Angel Fernandes, Emma Finch, Colleen Cassidy, Amy Fishman, Andrea Francis, Stacia Fritz, Simran Gill, Emma Gries, Rylie Hansen, Shannon Powers, Jacqueline Martinez, Zachary Harker, Ashley Hasty, Mykaela Tanino-Springsteen, Kathleen Hopps, Adelaide Kerenick, Colin Kleckner, Ci Koehring, Elijah Kruger, Braden Krumholz, Maddie Leake, Lyneé Alves, Seraphina Loukas, Yatzari Lozano Vazquez, Haley Maki, Emily Martinez, Sierra Mckinney, Audrey Mitchell, Kipling Newman, Audrey Ng, Megan Lucyshyn, Andrew Nguyen, Stevie Ostman, Casandra Pearson, Alexandra Penney, Julia Gielczynski, Tyler Ball, Anna Rini, Christina Rorres, Simon Ruland, Helayna Schafer, Emma Sellers, Sarah Schuller, Claire Shaver, Kevin Summers, Isabella Shaw, Madison Sinar, Claudia Pena, Apshara Siwakoti, Carter Sorensen, Madi Sousa, Anna Sparling, Alexandra Revier, Brandon Thierry, Dylan Tyree, Maggie Williams, Lauren Wols

DU Undergraduate Research Journal Archive

DU Undergraduate Showcase: Research, Scholarship, and Creative Works

Mutual Aid: The Other Law Of The Jungle. Gauthier Chapelle And Pablo Servigne. Cambridge, Polity Press. 2022. 310 Pp, Tom P. Flower Dr

Emancipations: A Journal of Critical Social Analysis

In 1902, the anarchist Peter Kropotkin published Mutual Aid in which he promoted a radical perspective on evolution in which cooperation, as well as selfishness, drive the form, diversification and organization of life on earth. Despite initial recognition, Kropotkin’s contributions have been largely forgotten, even as modern evolutionary theory has recognized the central role of cooperation. In Mutual Aid: the other law of the jungle, Pablo Servigne and Gauthier Chappelle restore Kropotkin’s insights to their rightful place as foundational for our understanding of evolution. They further seek to overturn the pernicious misconception of the 20^th century, that nature is …

An Argument For The Utilization Of Amphibian Stress As An Indicator Of Wetland Condition, Andrew W. Sisson

Honors College Theses

Traditional forms of rapid wetland condition assessments focus on foliage health, nutrient enrichment, chemical contamination, and surrounding land usage, often overlooking an evaluation of the animals living in the wetland. More intense assessments include the National Wetland Condition Assessment (NWCA) and indices of biotic integrity, which focus on community composition (e.g., diversity and species richness) and abundances. These indices require expertise in species identification and do not provide information about the animal’s fitness. Animal stress physiology, which generally correlates with measures used to quantify animal fitness (e.g., survival, reproduction, and body condition), may provide a complementary rapid assessment method aimed …

Measuring Selenoprotein Content In False Map Turtles (Graptemys Pseudogeographica) Along The Missouri River, Ruby A. Hawks

Honors Thesis

Metals and metalloids are becoming more prevalent in lakes and reservoirs of South Dakota which are toxic and hazardous in high concentrations or when biomagnified through trophic levels. Selenium is of particular concern as it can bind into the structures of proteins in place of other elements, changing protein structure and function within affected organisms. Zebra mussels (Dreissena polymorpha) are an invasive filter-feeding metal-bioaccumulating species that are rapidly spreading upstream through the Missouri River. They can take up selenium and directly transfer it to higher trophic level taxa. False map turtles (Graptemys pseudogeographica) are a common …

Macro And Micro-Nutrient Accumulation And Partitioning In Soybean Affected By Water And Nitrogen Supply, Ingrid Silva Setubal, Aderson Soares De Andrade Júnior, Silvestre Paulino Da Silva, Artenisa Cerqueira Rodrigues, Aurenívia Bonifácio, Evandro Henrique Figueiredo Moura Da Silva, Paulo Fernando De Melo Jorge Vieira, Rafael De Souza Miranda, Nicolas Cafaro La Menza, Henrique Antunes De Souza

West Central Research and Extension Center, North Platte

This study aimed to investigate the influence of water availability and nitrogen fertilization on plant growth, nutrient dynamics, and variables related to soybean crop yield. Trials were performed in Teresina, Piauí, Brazil, using randomized blocks in a split-split plot arrangement. The plots corresponded to water regimes (full and deficient), the split plots to N fertilization (0 and 1000 kg ha^-1 N-urea), and the split-split plots to harvest times of soybean plants (16, 23, 30, 37, 44, 58, 65, 79 and 86 days after emergence), with three replicates. In general, the accumulation and partitioning of nitrogen (N), phosphorus (P), potassium …

How Phylogeny And Arboreality Affect Pelvic Girdle Anatomy Of Chameleons, Dakota J. John

Honors Thesis

Morphological adaptations have allowed animals to inhabit different landscapes such as mountains, forests, plains, etc. These adaptations have increase in prevalence through natural selection processes in all species which allow favorable traits to be passed to offspring. Chameleons have evolved a plethora of adaptations that have allowed them to persist in different niches. One anatomical feature of chameleons that has not been well studied is the pelvic girdle. The pelvic girdle bridges the axial and appendicular skeletons in animals, so the size, shape, and orientation of the girdle is important to how the animal functions in its environment. The pelvic …

Meiofauna Distribution Patterns On A Sandy Beach Of Sapelo Island, Georgia, Nancy Dalman, Dianna Spence, Richard Settele, David Turner, Andrew Shirley, Jill Schulze

Georgia Journal of Science

Substantial abundance and diversity of intertidal invertebrates known as meiofauna are evident on a sandy beach of Sapelo Island, Georgia. Meiofauna are small, benthic, nearly ubiquitous animals. They consume microbes and detritus and are a food source for juvenile fish and ghost shrimp. Meiofauna were manually separated from sand samples collected from three intertidal zones and two depths during low tide in January, March, June, and October, 2017. Fifteen major meiofaunal clades were identified in June, while only eight were observed in January; in all, there were sixteen clades observed. Highest meiofauna densities were found in the middle intertidal zone …

Community And Population Dynamics Of Diatoms In Recovering Agricultural Stream And Ubiquitous Taxon In Low-Impact Sites Across Southeastern United States, Sydney Brown

Biology Theses

Streams play vital roles to surrounding communities and provide essential ecosystem services. The protection of streams is important, legally protected under the Clean Water Act (CWA) and can be monitored through the continuous analyses of biological data, like algal or other aquatic communities. Diatoms are a group of algae characterized by rigid glass cell walls and ubiquitous distribution. They are typically identified using the morphological species concept and an ever-varying range of sizes may pose challenges in the identification process. However, when identified and applied correctly, diatoms are robust bioindicators. This research identifies and analyzes low-impact sites across the Southeastern …

Assessing The Appropriateness Of Free-Roaming Cat Management Strategies Based On Resident Perspectives In A Small Pennsylvania Municipality, Brianna Marks

Electronic Theses and Dissertations

The popularity and mismanagement of free-roaming cats has resulted in invasive populations responsible for over-predation of birds and small mammals and increased disease transmission to humans and animals (Bies, 2014; Crowley et al., 2020). Management effectiveness fluctuates between communities due to varying opinions of free-roaming cats by governments and the public, which can influence management development and success (Deak et al., 2019). This research assesses the relationship between community perspectives of free-roaming cats and management. A survey of residents in a small Pennsylvania municipality was conducted with questions pertaining to free-roaming cats and management preferences in the community. Over 50% …