Physical Sciences and Mathematics Commons^™

Evaluating Potential For Water Quality Decline In Maine Lakes, Kaci N. Fitzgibbon

Electronic Theses and Dissertations

Understanding lake vulnerability with respect to eutrophication and loss of water quality is important for sustainability of aquatic ecosystems. This project aims at identifying and quantifying the effects of relevant physiochemical, climate, and watershed characteristics on lake vulnerability in order to develop management decision tools for the Maine Department of Environmental Protection (MEDEP). In a changing chemical and physical environment, using independent variables from each of these categories and then relating them to the summer lake epilimnetic phosphorus (P) concentrations allows for development of models to inform stakeholders of lake vulnerability to eutrophication problems.

We studied 24 lakes covering a …

Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard

Electronic Theses and Dissertations

ABSTRACT

Differential dissolution of gypsum karst within the Delaware Basin poses a significant threat to infrastructure that society depends on. The study area is located in Culberson County, Texas and traverses a distance of approximately 54 kilometers along RM 652 within the Gypsum Plain which is situated on the northern margin of the Chihuahua Desert and includes outcrops of Castile and Rustler strata that host karst geohazards. Regions of karst geohazard potential have been physically surveyed proximal to the study area in evaporites throughout the Castile Formation outcrop; minimal hazards, in comparison to the Castile Formation, have been documented in …

Using Hydroacoustics To Investigate Biological Responses In Fish Abundance To Restoration Efforts In The Penobscot River, Maine, Constantin C. Scherelis

Electronic Theses and Dissertations

Spatiotemporal advantages linked to hydroacoustic sampling techniques have caused a surge in the use of these techniques for fisheries monitoring studies applied over long periods of time in marine systems. Dynamic physical conditions such as tidal height, boat traffic, floating debris, and suspended particle concentrations result in unwanted noise signatures that vary in intensity and location within a hydroacoustic beam over time and can be mixed with the acoustic returns from intended targets (e.g., fish). Typical processing filters applied over long term datasets to minimize noise and maximize signals do not address spatiotemporal fluctuations of noise in dynamic systems. We …

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …

Spatiotemporal Analyses Of Recycled Water Production, Jana E. Archer

Electronic Theses and Dissertations

Increased demands on water supplies caused by population expansion, saltwater intrusion, and drought have led to water shortages which may be addressed by use of recycled water as recycled water products. Study I investigated recycled water production in Florida and California during 2009 to detect gaps in distribution and identify areas for expansion. Gaps were detected along the panhandle and Miami, Florida, as well as the northern and southwestern regions in California. Study II examined gaps in distribution, identified temporal change, and located areas for expansion for Florida in 2009 and 2015. Production increased in the northern and southern regions …

Remotely Sensed Heat : Variation And Change In Surface Urban Heat Islands In A Temperate Eco-Region Of The United States., Jeremy Sandifer

Electronic Theses and Dissertations

Urban heat island (UHI) is a term used to describe increased surface and atmospheric temperatures in an urban core relative to surrounding non-urbanized areas. To examine the variability introduced into derived estimates of the surface UHI, this study constructs and compares multiple remotely sensed indicators of the surface UHI for major metropolitan cities of a temperate eco-region of the United States. The Moderate Resolution Imaging Spectroradiometer (MODIS) 8-day, 500-meter product (MOD11A2) is the source data used to calculate six different RS-derived UHI indicators for the year 2002 to 2012. The different SUHI indicators are evaluated using the Spearmans Rho rank-order …

Assessment Of Watershed Condition And Vulnerability To Forecasted Land-Use/Land-Cover Change In The Northwestern Great Plains Of Western South Dakota, Aaron Suehring

Electronic Theses and Dissertations

A projected increase in global population by mid-century will likely further intensify agricultural practices given future demand for food, increasing the strain on the nation’s aquatic resources. Extensive water quality monitoring will be important in agriculturally dominated regions. The main objectives of this effort were to develop an approach to assess watershed condition and watershed vulnerability to land-use/landcover (LULC) change under multiple scenarios of future development. We used U.S. EPA’s Analytical Tools Interface for Landscape Assessment (ATtILA) to analyze landscape spatial data to determine the condition of wadeable, perennial stream watersheds in the Northwestern Great Plains level III ecoregion of …

Biotic Integrity In The Northwestern Great Plains And Mechanisms Regulating Stream Condition In South Dakota, Chad Kaiser

Electronic Theses and Dissertations

Anthropogenic disturbance of streams can alter biotic integrity in various ways. Some degradation is easy to classify and monitor, others such as habitat impairment may be less easy to quantify. The Index of Biotic Integrity (IBI) is a unique method of assessing the aquatic health of an ecosystem. Beginning in 2010 the South Dakota Department of Environment and Natural Resources (SD DENR) began implementing biological monitoring on wadeable streams by developing an IBI for the Northern Glaciated Plains ecoregion in eastern SD (Krause et al. 2013). Prior to this survey the condition of the majority of SD’s streams was unknown. …