Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 6 of 6

Full-Text Articles in Life Sciences

Inferring Food Web Structure To Identify Seasonal And Longitudinal Patterns In Ogeechee River Invertebrate Communities, Julien Marc Buchbinder Jan 2019

Inferring Food Web Structure To Identify Seasonal And Longitudinal Patterns In Ogeechee River Invertebrate Communities, Julien Marc Buchbinder

Electronic Theses and Dissertations

Understanding how the structure and function of aquatic communities vary across space and time is essential for proper management of freshwater ecosystems. Current management relies on rapid biomonitoring using metrics of community structure, but metrics that incorporate ecosystem processes and functions are only just beginning to see use in assessment and management. Food webs inferred from known species interactions have been proposed as a method of incorporating function into bioassessment without expending extra effort or sacrificing the cost-effectiveness of current monitoring schemes. To apply food webs in biomonitoring, it is first necessary to understand how communities and food webs vary …


Quantifying The Morphological And Physiological Effects Of Drought, Grass Invasion, And Fire On Longleaf, Loblolly, And Slash Pine, Laura Young Jan 2019

Quantifying The Morphological And Physiological Effects Of Drought, Grass Invasion, And Fire On Longleaf, Loblolly, And Slash Pine, Laura Young

Electronic Theses and Dissertations

Climate change is altering ecosystems on a global scale, creating novel ecological scenarios with which plant species must cope. Factors such as altered precipitation and fire regimes and non-native plant invasion may negatively affect native plant species, while interactions between these stressors could magnify their impacts. The complexity of multiple stressors and the effects they have on native pine seedlings are difficult to predict without evaluating their combinations in field experiments. In a multi-year study, I investigated the effects of drought and plant invasion on three southeastern pine species under pre and post-fire conditions. We planted longleaf (Pinus palustris …


The Role Of Local Adaptation On Biting Performance In Trinidadian Guppies, Hannah E. Cohen Jan 2019

The Role Of Local Adaptation On Biting Performance In Trinidadian Guppies, Hannah E. Cohen

Electronic Theses and Dissertations

Divergent selection pressures in populations that occupy different environments can result in phenotypic differentiation in traits that provide a local fitness advantage. Trinidadian guppy (Poecilia reticulata) populations are separated by physical barriers such as waterfalls which result in repeated shifts in selective pressures from predator avoidance in high predation environments towards resource competition in low predation environments. Such shifts in selection pressures have previously shown that a range of locally adapted morphological and behavioral traits are changed. However, the role of local adaptation on biting behaviors remains unclear. I analyzed morphological differences such as body length, jaw position, …


Effects Of Climate Variability: A Long-Term Perspective On Leaf Litter Processing In The Ogeechee River, Jose A. Sanchez Jan 2019

Effects Of Climate Variability: A Long-Term Perspective On Leaf Litter Processing In The Ogeechee River, Jose A. Sanchez

Electronic Theses and Dissertations

The Intergovernmental Panel for Climate Change (IPCC) predicts a rise in temperatures and changes to precipitation patterns for the 21st century. These changes are expected to lead to a higher frequency of extreme events such as drought and floods which lead to the alteration of the hydrology, communities, and processes of freshwater ecosystems. Leaf litter decomposition in stream ecosystems is an important component of the energy and nutrient cycle representing a food source for aquatic organisms. This has made it a tool for assessing long term responses to disturbance due to changes in the assemblage of macroinvertebrates that …


Wetland Biogeochemical Responses To Predicted Climate Change Scenarios, Angela R. Shaffer Jan 2019

Wetland Biogeochemical Responses To Predicted Climate Change Scenarios, Angela R. Shaffer

Electronic Theses and Dissertations

Wetlands are one of the world's largest known carbon sinks while comprising only a small amount of the Earth's surface. However, the amount of carbon sequestered by wetlands is shrinking as droughts and human disturbance increases. Carbon in wetlands is stored through the contrast of decomposition and sedimentation of organic matter and absorption of CO2 from the atmosphere by soil microbes. Understanding how changing hydrological regimes and increased wildfires will affect wetland soil and microbial processes is important in the face of predicted climate change for future wetland conservation practices. Specifically, I seek to understand the response of southeastern …


Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer Jan 2019

Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer

Electronic Theses and Dissertations

The intestinal microbiome of mammals plays a significant role in host health and response to environmental stimuli and can include both beneficial native bacteria as well as parasitic worms. In this study, I examined the intestinal cestode and bacterial communities of two closely related species of shrew, Sorex monticola and Sorex cinereus, over a six month period in 2016. Specimens were collected approximately every three weeks from May to October from the Sangre de Cristo Mountains in Cowles, New Mexico. A total of 79 shrews were prepared with the gastrointestinal tracts removed and flash-frozen in liquid nitrogen. An additional …