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Full-Text Articles in Physical Sciences and Mathematics

Groundwater Hydrogeolgy And Hydrochemistry Of Karst Springs In The Eastern Peninsula Of Fort Hood Military Installation, William Scribner Welles Dec 2018

Groundwater Hydrogeolgy And Hydrochemistry Of Karst Springs In The Eastern Peninsula Of Fort Hood Military Installation, William Scribner Welles

Electronic Theses and Dissertations

The eastern peninsula of Fort Hood Military Installation is underlain by a complex karst spring network. These springs are a primary water source in a protected habitat for endangered songbirds, which has only recently begun to be fully investigated. These Fredericksburg Group springs express both epigenetic and hypogenetic karst signatures. The study area is part of a paleo reef trend, a hydraulically disconnected segment of the northern section of the Edwards Aquifer. This study utilized standard ion index values, repeated measures, and principal component analyses on the chemical profiles of six perennial springs to classify spring water sources and their …


Effectiveness Of Prescribed Fire On Meeting Fuel Load And Wildlife Habitat Management Objectives In East Texas National Forests, Trey Wall Dec 2018

Effectiveness Of Prescribed Fire On Meeting Fuel Load And Wildlife Habitat Management Objectives In East Texas National Forests, Trey Wall

Electronic Theses and Dissertations

Using standardized methodology outlined by the United States Forest Service and the National Forests and Grasslands in Texas’ Fire Monitoring Program for data collection, the efficacy of current Forest Service prescribed burn regimes were analyzed for 24 study sites in East Texas National Forests. Study sites were located within Sam Houston, Davy Crockett, and Angelina/Sabine National Forests. Efficacy was determined by comparing defined management objectives established by the Forest Service to the data collected at the study sites. The results conclude that most objectives, as outlined by the Forest Service, are not being met with the current practices. Re-visitation of …


Economics Of Managing Loblolly Pine Plantations For Increased Wildlife Biodiversity, Melissa Griffith Aug 2018

Economics Of Managing Loblolly Pine Plantations For Increased Wildlife Biodiversity, Melissa Griffith

Electronic Theses and Dissertations

The goal of this thesis was to identify the differences between the costs incurred and revenues gained from managing loblolly pine (Pinus taeda) plantations in East Texas for strictly timber production or a combination of timber production and wildlife biodiversity. Management regimes evaluated had varying planting densities, thinning frequency and intensities, prescribed burn intervals, and site indices. Economic analyses used to evaluate management regimes over a range of nonindustrial private landowner (NIPF) alternative rates of return (ARRs) and site indexes were net present worth, land expectation value, and equal annual annuity. These economic analyses demonstrated that altering management …


Speleogenetic Evolution And Geological Remote Sensing Of The Gypsum Plain, Eddy County, New Mexico, Jessica Shields May 2018

Speleogenetic Evolution And Geological Remote Sensing Of The Gypsum Plain, Eddy County, New Mexico, Jessica Shields

Electronic Theses and Dissertations

Permian evaporites of the Gypsum Plain region of the Delaware Basin host extensive karst phenomena, as well as unique diagenetic alterations of host strata. Because of the complex, poorly understood hydrogeologic system, little has been established concerning the relation and evolution of the overprinted, modern and ancient karst manifestations within the Gypsum Plain, as a whole. Through a combination of traditional field studies and the development of improved remote sensing methodologies, this study established the speleogenetic evolution of the Gypsum Plain in relation to the greater tectonic, stratigraphic, hydrogeologic and climatic history of the Delaware Basin. Emphasis was focused on …


Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish May 2018

Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish

Electronic Theses and Dissertations

Of the most iconic fish species in the world, the Atlantic cod (Gadus morhua, hereafter, cod) has been a mainstay in the North Atlantic for centuries. While many global fish stocks have received increased pressure with the advent of new, more efficient fishing technology in the mid-20th century, exceptional pressure has been placed on this prized gadoid. Bycatch, or the unintended catch of organisms, is one of the biggest global fisheries issues. Directly resulting from the failed recovery of cod in the GoM, attention has been placed as to possible sources of unaccounted catch. Among the most …


A Comparison Of Four Wetlands Assessment Procedures Relevant To The Alluvial Valleys Of East Texas, Amy Camp May 2018

A Comparison Of Four Wetlands Assessment Procedures Relevant To The Alluvial Valleys Of East Texas, Amy Camp

Electronic Theses and Dissertations

Currently several methods are used by public and private entities to assess wetland functional condition in support of the Section 404 Clean Water Act program. Four of these are: Forested Wetlands in Alluvial Valleys of the Coastal Plain of the Southeastern United States (SEHGM); A Regional Guidebook for Applying the Hydrogeomorphic Approach to the Functional Assessment of Forested Wetlands in Alluvial Valleys of East Texas (ETXHGM); Texas Rapid Assessment Method (TXRAM); and the Wildlife Habitat Appraisal Procedure (WHAP). Little previous research compares wetland functional assessment methods. Results of the SEHGM, ETXHGM, TXRAM, and WHAP methods were compared on five East …


Marine Protected Areas In Areas Beyond National Jurisdiction: Defining "Success" For Conservation And Management, Emily Suzanne Nocito May 2018

Marine Protected Areas In Areas Beyond National Jurisdiction: Defining "Success" For Conservation And Management, Emily Suzanne Nocito

Electronic Theses and Dissertations

With growing attention to and use of marine protected areas [MPAs], there are an increasing number of policy goals ascribed to these area-based management tools [ABMT]. One expectation is that an MPA can increase system “resilience”, yet oftentimes resilience – including whether we are considering social, economic or ecological resilience – stays unspecified. In recent years, there has also been a specific focus on MPAs as tools to promote climate change resilient ocean systems. Through a meta-analysis of the scientific literature and an analysis of over one thousand three hundred voluntary commitments made at the United Nation Ocean Conference, this …


An Examination Of Beta Diversity Indices And Their Predictors In Two Large-Scale Systems, Philip Schroeder Jan 2018

An Examination Of Beta Diversity Indices And Their Predictors In Two Large-Scale Systems, Philip Schroeder

Electronic Theses and Dissertations

Biodiversity is what conservation biology was developed to conserve. It is the physical manifestation of life as a concept and, be it for practical or idealistic reasons, all conservationists seek to protect or, in some cases, enhance it. Because of its monolithic importance to the field, much effort has been expended trying to better measure and understand it. Recently, greater attention has been paid to the partition of diversity; the observation that the total diversity of a system (γ) can be broken down into within-site diversity (α) and between-site diversity (β). In particular, it has been noticed that the β …


The Ecology Of Land Managers In Riparian Restoration, Lisa Buie Clark Jan 2018

The Ecology Of Land Managers In Riparian Restoration, Lisa Buie Clark

Electronic Theses and Dissertations

While previous studies in restoration ecology have focused on the efficacy of direct management actions, the driving forces on management decisions (e.g., managers' characteristics or attitudes, environmental conditions) and the indirect impacts on restoration outcomes from management decisions (such as whether to collaborate) are quantified here for the first time. As a case study, I used data from 244 sites across the riparian Southwest US where the invasive shrubby tree Tamarix sp. was removed using various different methods. I surveyed and interviewed the 45 land managers who were responsible for the removal projects to determine their characteristics, attitudes, and …


Evolution And Distribution Of Phenotypic Diversity In The Venom Of Mojave Rattlesnakes (Crotalus Scutulatus), Jason Strickland Jan 2018

Evolution And Distribution Of Phenotypic Diversity In The Venom Of Mojave Rattlesnakes (Crotalus Scutulatus), Jason Strickland

Electronic Theses and Dissertations

Intraspecific phenotype diversity allows for local adaption and the ability for species to respond to changing environmental conditions, enhancing survivability. Phenotypic variation could be stochastic, genetically based, and/or the result of different environmental conditions. Mojave Rattlesnakes, Crotalus scutulatus, are known to have high intraspecific venom variation, but the geographic extent of the variation and factors influencing venom evolution are poorly understood. Three primary venom types have been described in this species based on the presence (Type A) or absence (Type B) of a neurotoxic phospholipase A2 called Mojave toxin and an inverse relationship with the presence of snake venom metalloproteinases …