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Full-Text Articles in Life Sciences

Relationships Between Stream Geomorphology And Fish Community Structure And Diversity In Maine, Emily Gaenzle Aug 2002

Relationships Between Stream Geomorphology And Fish Community Structure And Diversity In Maine, Emily Gaenzle

Electronic Theses and Dissertations

Predicting patterns in species distribution and abundance for resource management and conservation is a major focus of applied ecology. The primary objective of this study was to determine if there is a predictable relationship between stream geomorphology and fish community structure, native species richness, and native salmonid abundance in Maine. Specifically, I examined relationships between fish assemblages and geomorphic stream types, as delineated by the Rosgen classification system (Rosgen 1996). Fifty-three stream reaches in Maine were classified, and fish communities within the reaches were characterized using backpack electrofishing. Species richness was lowest in A-type streams (i.e., steep, entrenched, confined), which …


Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock Aug 2002

Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock

UNLV Theses, Dissertations, Professional Papers, and Capstones

Five geomorphic surfaces present in the northern Pahranagat Valley, Lincoln County, Nevada range in age from Early Pleistocene to Recent (Q1-Q5) and vary in clast lithology from dolomite to volcanic tephras. Two chronosequences and 5 lithosequences were compared to evaluate micro and macromorphic characteristics and development of soil pendants. This study presents a new interpretation for soil pendant development. Key features observed in the Pahranagat Valley pendants provide evidence for precipitation at the clast-pendant contact suggesting that newer deposits are not always found at the pendant terminus as other studies have assumed. These features include a void at the clast-pendant …


Communicator-In-Chief: Presidential Use Of Television Past, Present, And Future, Jenna Wasson May 2002

Communicator-In-Chief: Presidential Use Of Television Past, Present, And Future, Jenna Wasson

Honors Theses

This thesis seeks to determine how television has changed as a communication medium for presidents over the past half century. An evaluation of the evolving ways presidents use television to communicate with and to build support from the American people has been conducted. Presidential communication strategies have been identified by drawing primarily from primary sources written by presidents and White House staff. Television technology and the television audience have changed over the years. Presidents have taken a more pro-active, aggressive role in their efforts to harness television for their own purposes. Why have these changes occurred? What impact have these …


Application Of Biophysical Data To An Unsupervised Classification To Map Ecoregional Boundaries In The Desert Southwest, Paxton R. Mcclurg May 2002

Application Of Biophysical Data To An Unsupervised Classification To Map Ecoregional Boundaries In The Desert Southwest, Paxton R. Mcclurg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An unsupervised classification was applied to continuous biophysical variables in an attempt to delineate ecoregional boundaries in the desert southwest. Output was then compared with ecoregions delineated by the Natural Resources Conservation Service (NRCS), the Environmental Protection Agency (EPA), and the Forest Service at the national level. An attempt was made to use the same biophysical variables for input into the unsupervised classification as was emphasized by the various agencies with their ecoregional classifications at the desert level. Major constraints included data availability at such a large study area, data resolution, and data that were continuous. This eliminated categorical data …


The Role Of Forest Soils In A Northern New England Effluent Management System, Leslie B. Nelson May 2002

The Role Of Forest Soils In A Northern New England Effluent Management System, Leslie B. Nelson

Electronic Theses and Dissertations

The Carrabassett Valley Sanitary District in Carrabassett Valley, Maine has utilized both a forest spray irrigation system and a Snowfluent™ system for the treatment of their wastewater effluent. This study was designed to evaluate potential changes in soil properties after approximately 20 years of treatment in the forested spray irrigation site and three years of treatment in the field Snowfluent™ site. In addition, grass yield and composition were evaluated on the field study sites. After treatment with effluent or Snowfluent™, soils showed an increase in soil exchangeable Ca, Mg, Na, and K, base saturation, and pH. While most constituents were …


Bioavailability/Toxicity Of Iron From Aerobically Processed Organic Fertilizer, Stacey Marie Wilson May 2002

Bioavailability/Toxicity Of Iron From Aerobically Processed Organic Fertilizer, Stacey Marie Wilson

Undergraduate Honors Capstone Projects

For an undergraduate Honor's project, I worked under the direction of Dr. Jeffery Hall to determine the bioavailability and toxicity of iron from Milorganite® fertilizer, an aerobically processed organic fertilizer. The Milorganite® Company is a subsidiary of the Milwaukee Municipal Sewage District and produces a fertilizer of high iron content (approximately 5-7%). The high iron content has resulted in concern about the toxic potential, which until now was unknown. This thesis paper will explain iron chemistry, bioavailability, requirements, absorption, toxicity, and treatments, followed by a description of fertilizer types and contents. This will be followed by a description and reasoning …


A Gis Approach For The Abandoned Mine Inventory With Haul Roads Of The Monongahela National Forest To Provide A Comparative Analysis Of Usfs/Usace Collection Procedures And Image Basemap Selection For Cartographic Representation, John R. Ferguson Ii Jan 2002

A Gis Approach For The Abandoned Mine Inventory With Haul Roads Of The Monongahela National Forest To Provide A Comparative Analysis Of Usfs/Usace Collection Procedures And Image Basemap Selection For Cartographic Representation, John R. Ferguson Ii

Theses, Dissertations and Capstones

The Monongahela National Forest spans 10 counties in eastern central West Virginia. It has been an area of high mining and timbering activities throughout much of the early to mid twentieth century. As a result, the United States Forest Service (USFS) has focused reclamation and remediation efforts on the abandoned mine land areas. Much of the area has been subjected to mining after effects such as acid mine drainage, structural remains, gob/spoil piles, garbage piles, mine portals, and highwalls. In 1998 the USFS contracted with the U.S. Army Corps of Engineers (USACE) to locate these mining remains and provide a …


Fate Of Organic Compounds Associated With Extractable And Bound Phases Of Estuarine Sediments Deposited Under Varying Depositional Regimes, Krisa Murray Arzayus Jan 2002

Fate Of Organic Compounds Associated With Extractable And Bound Phases Of Estuarine Sediments Deposited Under Varying Depositional Regimes, Krisa Murray Arzayus

Dissertations, Theses, and Masters Projects

Surficial sediments and sediment cores were collected from two distinct depositional regimes of the York River subestuary of Chesapeake Bay to document seasonal inputs, spatial variability, and longer-term (>40 years) fate of total organic carbon (TOC), lipid biomarker compounds and polycyclic aromatic hydrocarbons (PAHs). These regimes included biological mixing in the lower York and episodic mixing at the mid river site. Compounds were selected to represent a range of chemical reactivities, biological and anthropogenic sources, and modes of entry to the environment. The depositional environments were characterized with a suite of analytical tools: x-radiographs, Eh, 210Pb and 137Cs, total …


Organic Matter Cycling In The York River Estuary, Virginia: An Analysis Of Potential Sources And Sinks, Leigh Mccallister Jan 2002

Organic Matter Cycling In The York River Estuary, Virginia: An Analysis Of Potential Sources And Sinks, Leigh Mccallister

Dissertations, Theses, and Masters Projects

A study of the organic matter (OM) sources and biogeochemical and physicochemical sinks was undertaken in the York River estuary, Virginia. The reactivity of dissolved organic carbon (DOC) was enhanced from ∼25--68% by the combined effects of exposure to natural sunlight and bacterial decomposition. In contrast, sunlight exposure decreased the bioreactivity of DOC in the higher salinity lower York by a factor of five. The combined effects of photochemical and bacterial processing were found to modify both the bioavailability and metabolic fate of OM (e.g. respiration vs. biomass). Stable isotopic (delta13C, delta15N) and radiocarbon (Delta14C) values of bacterial nucleic acids …


Growth Increment Analysis Of Marine Bivalves From The North, Stephen D. Houk Jan 2002

Growth Increment Analysis Of Marine Bivalves From The North, Stephen D. Houk

Electronic Theses and Dissertations

This study aids in developing a sea surface temperature (SST) proxy with monthly temporal resolution using a combination of growth increment and stable isotope analyses of marine bivalves from the north coast of Peru. Faunal assemblages from the Siches and Ostra Base Camp archaeological sites contain shells of warm-tropical mollusks that currently live farther north in Ecuador. The presence of warm-tropical species in these sites and others as far south as 10"s latitude and dating prior to 5730 cal yr B.P. indicates a stable warm-water regime in the eastern tropical Pacific which subsequently changes to a modern temperate-water regime after …