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Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby

Master's Theses

This study examined the effects that water table depth and soil characteristics have on plant species richness and species composition within pitcher plant bogs across seasons. Eight piezometers were installed at random distances to monitor long-term water table depth and pressure fluctuations along a ~710-meter line transect traversing upland and bog habitats. Vegetation sampling quadrats (n=128) were set up near each piezometer. Cover data and water table depths were collected in spring and late summer. Soil samples collected from each treatment group were used to obtain soil texture and nutrient data. The summer collection period yielded a total gdiversity of …

Non-Invasive Methods For Measuring And Monitoring Stress Physiology In Imperiled Amphibians, Edward J. Narayan, Zachery R. Forsburg, Drew R. Davis, Caitlin R. Gabor

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Global climate change is negatively impacting global biodiversity and ectothermic vertebrates, with amphibians being the most imperiled vertebrate taxa. Increased mean global atmospheric temperatures, high rates of habitat degradation, and exposure to infectious diseases, such as chytridiomycosis, have contributed to population declines and extinctions of rare and endangered amphibian species. Field-based monitoring of physiological endocrine traits can help determine the sub-lethal effects of environmental stressors and provide early alerts when populations are chronically stressed. Recent advances in amphibian stress endocrinology include the development and use of non-invasive methods to quantify the glucocorticoid, or stress biomarker, corticosterone. Non-invasive methods, such as …

Increasing Impacts Of Extreme Droughts On Vegetation Productivity Under Climate Change, Chonggang Xu, Nate G. Mcdowell, Rosie A. Fisher, Liang Wei, Sanna Sevanto, Bradley O. Christoffersen, Engsheng Weng, Richard S. Middleton

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Terrestrial gross primary production (GPP) is the basis of vegetation growth and food production globally1 and plays a critical role in regulating atmospheric CO2 through its impact on ecosystem carbon balance. Even though higher CO2 concentrations in future decades can increase GPP2, low soil water availability, heat stress and disturbances associated with droughts could reduce the benefits of such CO2 fertilization. Here we analysed outputs of 13 Earth system models to show an increasingly stronger impact on GPP by extreme droughts than by mild and moderate droughts over the twenty-first century. Due to a dramatic increase in …

Traffic Noise And Sexual Selection: Studies Of Anthropogenic Impact On Bird Songs And Undergraduate Student Reasoning Of Evolutionary Mechanisms, Sarah Spier

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

Humans have transformed much of the natural landscape and are continuing to do so at an accelerated rate, compromising natural areas that serve as important habitat for many species. Roads impact much of the environment as they fragment habitat and introduce traffic noise into the acoustic environment, deferentially affecting wildlife in roadside habitat. I explored how traffic noise affects the detection of birds based on whether their vocalizations were masked by traffic noise. Masked species detection was not affected by an increase in traffic noise amplitude, while there was a negative effect of traffic noise amplitude on unmasked species detection, …

Changes In Mammalian Abundance Through The Eocene-Oligocene Climate Transition In The White River Group Of Nebraska, Usa, Robert Gillham

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Marine records show major cooling during the Eocene-Oligocene Climate Transition (EOCT). Most proxy studies in the White River Group suggest drying across the EOCT, and some suggest cooling. The lower resolution continental record has hindered a direct correlation of the marine climate record to Nebraska. I explore various correlation schemes and what they imply for faunal changes. This study compiles and analyzes data from 4,875 specimens in the University of Nebraska State Museum (UNSM) collection to test the hypothesis that climate change across the Eocene-Oligocene (E-O) boundary caused significant abundance changes in mammals. A series of binning schemes was created. …

Agricultural Intensification And Urbanization Negatively Impact Soil Nematode Richness And Abundance: A Meta-Analysis, Satyendra K. Pothula, Parwinder Grewal, Robert M. Auge, Arnold M. Saxton, Ernest C. Bernard

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Human activity has extensively transformed the land surface by agricultural intensification and urbanization. In soil, nematodes are the most abundant invertebrates. The effect of human interventions was assessed on overall richness, overall abundance, richness and abundance of nematodes of each trophic group and colonizer-persister (c-p) guild by comparing urban, agriculture and disturbed grassland (DGL) with natural grassland (NGL) and forest ecosystems. Meta-analyses were conducted to generate quantitative summaries from 111 published articles that met the inclusion criteria, 91 expressed data in grams and 20 expressed data in cm3. Results from data expressed per 100 g of soil indicated that overall …

Effects Of Amur Honeysuckle On Soil Co2 Emissions, Aidan Shumaker

Student Symposium

Lonicera maackii is an invasive woody species found in Ohio and throughout the deciduous forests of eastern United States, taking over habitats of native shrub species such as Lindera benzoin. L. maackii has unique traits compared to deciduous forest natives, showing earlier leaf-out and later leaf senescence, higher leaf nitrogen levels, and faster leaf decomposition. As a result, L. maackii may alter soil conditions through its extended root activity and impacts on microbial decomposition, possibly impacting soil CO2 emissions. As soil microorganisms metabolize organic matter, they release greenhouse gases like CO2 through respiration, which can impact global climate change. Previous …

Benthic Foraminiferal Assemblages From Marshes And Mangroves In The Everglades (South Florida, Usa) And Their Application As Proxies For Habitat Shifts Due To Sea Level Rise, Zoe Verlaak

FIU Electronic Theses and Dissertations

This study examined benthic foraminifera from marsh and mangrove environments along the coasts of the Everglades in South Florida for their use as proxies for salinity and applied the results to assess the nature and rates of past habitat changes due to sea level rise over the last ~3400 years. Research on modern foraminiferal assemblages from the Everglades are scarce, and this is the first foraminifera-based paleoenvironmental study for this region.

The study of living assemblages examined the extent to which infaunal foraminifera bias modern and fossil assemblages, and which sediment interval should be used as a modern analog for …

Betting & Hierarchy In Paleontology, Leonard Finkelman

Faculty Publications

In his Rock, Bone, and Ruin: An Optimist’s Guide to the Historical Sciences, Adrian Currie argues that historical scientists should be optimistic about success in reconstructing the past on the basis of future research. This optimism follows in part from examples of success in paleontology. I argue that paleontologists’ success in these cases is underwritten by the hierarchical nature of biological information: extinct organisms have extant analogues at various levels of taxonomic, ecological, and physiological hierarchies, and paleontologists are adept at exploiting analogies within one informational hierarchy to infer information in another. On this account, fossils serve the role …

Vegetation Sensitivity During The Mid-Holocene Warming In Western Ohio, Kristin Kopera

Browse all Theses and Dissertations

There has been a growing interest in prairie reconstruction in western Ohio, yet there are few recent academic sources supporting the claim that prairies appeared in western Ohio during the mid-Holocene. The hypsithermal was the warmest and driest part of the Holocene and occurred from 8,000-4,000 years ago in the Midwest. During the hypsithermal, the Prairie Peninsula appeared from Minnesota to eastern Ohio. If prairie did appear in Ohio, it occurred during the mid-Holocene hypsithermal. The goal of this study was to determine if western Ohio experienced a prairie period during the hypsithermal using pollen as a proxy for past …