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A Comparison Of The Ecological Integrity Of Headwater Streams Draining Harvested And Un-Harvested Watersheds In The Western Mountains Of Maine, U.S.A., Darlene Siegel Dec 2003

A Comparison Of The Ecological Integrity Of Headwater Streams Draining Harvested And Un-Harvested Watersheds In The Western Mountains Of Maine, U.S.A., Darlene Siegel

Electronic Theses and Dissertations

Physical, chemical, and biological characteristics of four headwater streams draining forested watersheds were compared to determine the effectiveness of Riparian Management Zones (RMZs) in protecting aquatic ecological integrity from the effects of forest harvesting. Two of the watersheds were harvested with a 30% sheltenvood cut and a 75 foot buffer was left adjacent to the streams. The other two watersheds were un-harvested and were used as reference conditions for comparison with the harvested watersheds. General environmental conditions in these four headwater streams during the study period were characterized as follows. Each stream was located within a mixed- wood forest dominated …


Susceptibility Of Adult Colorado Potato Beetle (Leptinotarsa Decemlineata) To The Fungal Entomopathogen Beauveria Bassiana, Ellen Klinger Aug 2003

Susceptibility Of Adult Colorado Potato Beetle (Leptinotarsa Decemlineata) To The Fungal Entomopathogen Beauveria Bassiana, Ellen Klinger

Electronic Theses and Dissertations

Factors influencing the susceptibility of adult Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), to the fungal entomopathogen, Beauveria bassiana (Bals.), were studied. In an assay comparing trials between a): laboratory reared, non-diapausing beetles and b): field collected, post-diapausing beetles, survival of B. bassiana treated beetles was higher for non-diapausing adults, however, control mortality was higher for post-diapausing adults. In a similar assay with field collected pre- and post-diapausing beetles, survival of B. bassiana treated individuals was higher for post-diapause adults and control mortality was higher for post-diapausing adults than pre-diapausing beetles. In a third experiment, the effect of time from …


Hydroperiod Of Wetlands And Reproduction In Wood Frogs (Rana Sylvatica) And Spotted Salamanders (Ambystoma Maculatum), Mary Beth Kolozsvary Aug 2003

Hydroperiod Of Wetlands And Reproduction In Wood Frogs (Rana Sylvatica) And Spotted Salamanders (Ambystoma Maculatum), Mary Beth Kolozsvary

Electronic Theses and Dissertations

Many amphibians rely on wetlands for reproduction and the differential distribution of amphibian species along a gradient of wetland permanence is striking, yet not absolute. Wood frogs (Rana sylvatica) and spotted salamanders (Ambystoma maculatum) are thought to rely on seasonal wetlands for greatest breeding success, but there is little documentation of their reliance on these or other habitats. In my first chapter, I studied these species in wetlands across a hydrologic gradient from seasonal wetlands of short flood duration to permanently flooded sites. My results indicate that wood frogs have greatest reproductive effort and success in …


Travel Time Study At The Wetlands Park National Preserve, Brandon Bair May 2003

Travel Time Study At The Wetlands Park National Preserve, Brandon Bair

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis reports on a study of the residence time of water in the Wetlands Park Nature Preserve in Henderson, Nevada. Rhodamine WT was used in order to test for the travel time of the water from the Monson Channel inflow to the Nature Preserve outflow to the Las Vegas Wash. The initial hypothesis was that the water would stay in the system for approximately 8 days. Residence time was tested using an ISCO sampling machine along with a Sequoia-Turner model 450 fluorimeter to test for the fluoresce of the dye in the water. All samples collected were taken immediately …


Modeling Habitat Quality For American Martens In Western Newfoundland, Canada, William A. Adair May 2003

Modeling Habitat Quality For American Martens In Western Newfoundland, Canada, William A. Adair

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The "Den Mother" marten habitat quality models were created to provide insight into American marten habitat selection behavior and to promote the recovery of the Newfoundland marten (Martes americana atrata) population. Although these objectives are typical of most wildlife habitat modeling projects, the marten's idiosyncratic habitat ecology and apparently intractable conflicts associated with timber harvesting motivated a unique, process-oriented approach to appraising landscapes. The Den Mother models used optimal decision-making principles to synthesize critical resources (den sites and foraging opportunities) and constraints (adverse thermal situations and exposure to predations) into a single hierarchical framework. The resulting spatially explicit, …


The Short And Long-Term Effects Of Herbicide Application In Maine Clearcuts On Ant Communities (Hymenoptera: Formicidae), Kerry Frances Lough May 2003

The Short And Long-Term Effects Of Herbicide Application In Maine Clearcuts On Ant Communities (Hymenoptera: Formicidae), Kerry Frances Lough

Electronic Theses and Dissertations

The short and long-term effects of glyphosate application on the diversity and abundance of ants in Maine clearcuts was assessed in a two-year study. Glyphosate is applied to release coniferous trees from suppression by competition with deciduous vegetation after a forest is clearcut. Previous research indicates glyphosate has limited immediate and long-term effects on non-target fauna, though specific species can be affected. Limited research on the effects of herbicides on insects indicates some initial decrease in insect populations. Beneficial insects, such as pollinators and predators, positively influence the forest ecosystem, but little research has examined the effects of herbicide application …


The 100th Meridian Initiative In Nevada: Assessing The Westward Movement Of The Zebra Mussel To The Lake Mead National Recreation Area, Megan Mccoy May 2003

The 100th Meridian Initiative In Nevada: Assessing The Westward Movement Of The Zebra Mussel To The Lake Mead National Recreation Area, Megan Mccoy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zebra mussels, Dreissena polymorpha, are a concern for all bodies of water in North America. East of the 100th Meridian, zebra mussels have infested the waters and dramatically changed the natural ecosystems. The US Fish and Wildlife Services set up the 100th Meridian Initiative project to monitor the boat traffic to and from infested and non-infested waters of the United States and Canada. Surveys were conducted from October 19, 2002 through March 31, 2003, focusing specifically on the Lake Mead National Recreation Area (LMNRA) for the scope of this thesis. This study addresses the movement of trailers, boats, and other …


Fluctuations In Chinook Salmon (Oncorhynchus Tshawytscha) Counts At Three Lower Columbia River Spawning Sites, Eric Michael Loomis May 2003

Fluctuations In Chinook Salmon (Oncorhynchus Tshawytscha) Counts At Three Lower Columbia River Spawning Sites, Eric Michael Loomis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Several hypotheses were developed to explore the pronounced increase in Chinook salmon (Oncorhynchus tshawytscha) returning to spawning grounds at the Cowlitz, Kalama, and Lewis Rivers, three tributaries of the lower Columbia River. The study was conducted using data compiled over a ten-year span from 1991-2001. Preliminary indications are that trends in climate are linked to these increases, with the absence of El Niño events and fluctuations in winter precipitation as likely explanations of these phenomena. The unique nature of Chinook life cycles causes them to utilize a variety of habitats that require ideal conditions for maximum survival rates. Correlations between …


Determining The Factors That Control Respiration And Carbon Use Efficiency In Crop Plants, Jonathan M. Frantz May 2003

Determining The Factors That Control Respiration And Carbon Use Efficiency In Crop Plants, Jonathan M. Frantz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the literature on plant respiration, there are two viewpoints concerning the source of respiratory control: supply (photosynthate availability) or demand (temperature dependent) limitations. While different studies indicate the primary dependency for respiration is either the supply or demand side, the two paradigms cannot both be true. The relative importance of each paradigm may depend on a number of factors including period of time during which respiration is measured, phase of plant development, environmental conditions, and species.

Studies were performed using continuous CO2 gas-exchange instrumentation to monitor short- and long-term changes in whole canopies of lettuce, tomato, soybean, and …


Breeding Bird Communities Of Major Mainland Rivers Of Southeastern Alaska, Jim A. Johnson May 2003

Breeding Bird Communities Of Major Mainland Rivers Of Southeastern Alaska, Jim A. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Because of the scarcity of information for bird communities at the major mainland rivers of southeastern Alaska, the main objective of this study was to provide baseline information including distribution, status, and habitat associations of breeding birds.

I conducted a meta-analysis of all known reports (including the current study) conducted at major mainland rivers during the breeding season. I described bird species composition, distribution, abundance estimates, status, habitat associations, and guild membership for all birds recorded at 11 major mainland rivers. Based on incidental observations, 170 species were recorded by all studies. Of these, 134 species were known or suspected …


An Analysis Of Materials Suitable For Use As A Pitfall Trap In A Desert Environment, R. Renee Brown Apr 2003

An Analysis Of Materials Suitable For Use As A Pitfall Trap In A Desert Environment, R. Renee Brown

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to identify a type of pitfall trap container that can withstand the temperature extremes of the Mojave Desert in which the terrestrial, or above ground, drift fence with pitfall traps will be utilized for trapping reptiles. A pitfall trap is a container, such as a plastic bucket with a plastic lid, that is buried in the ground up to the lip of the bucket and used to catch small ground dwelling fauna that fall into the trap. Many different pitfall trap materials have been utilized in the trapping of small ground-dwelling fauna. Plastic has …


A System Dynamics Investigation Of Genetic Drift And Translocation In The Red-Cockaded Woodpecker Metapopulation, Jason E. Yates Mar 2003

A System Dynamics Investigation Of Genetic Drift And Translocation In The Red-Cockaded Woodpecker Metapopulation, Jason E. Yates

Theses and Dissertations

The red-cockaded woodpecker (Picoides borealis) is classified under the Endangered Species Act of 1973 as an endangered species As such, the red-cockaded woodpecker (RCW) is afforded strict protection in an effort to return the RCW population to a self-sustainable level. Endemic to southeastern United States mature pine forests, the presence of the RCW impacts the operations of many Department of Defense (DoD) installations. A particular challenge in sustaining what are often small populations of RCW at these locations is the loss of genetic variation due to genetic drift. The optimal method for mitigating such loss is through the artificial immigration, …


Persistent Organic Pollutants At The Base Of The Antarctic Marine Food Web, Amy Lee Chiuchiolo Jan 2003

Persistent Organic Pollutants At The Base Of The Antarctic Marine Food Web, Amy Lee Chiuchiolo

Dissertations, Theses, and Masters Projects

No abstract provided.


Bioavailability Of Polybrominated Diphenyl Ethers (Pbdes) In Biosolids And Spiked Sediment To The Aquatic Worm Lumbriculus Variegatus, Serena Ciparis Jan 2003

Bioavailability Of Polybrominated Diphenyl Ethers (Pbdes) In Biosolids And Spiked Sediment To The Aquatic Worm Lumbriculus Variegatus, Serena Ciparis

Dissertations, Theses, and Masters Projects

No abstract provided.


Metal Concentrations In Deep-Sea Mussels From A Hydrothermal Vent And Cold Seep, Shana Rapoport Jan 2003

Metal Concentrations In Deep-Sea Mussels From A Hydrothermal Vent And Cold Seep, Shana Rapoport

Dissertations, Theses, and Masters Projects

No abstract provided.


Determination Of Home Techniques For Storing And Conserving Food In The Homes Of Cuambo And La Rinconada In Imbabura Province, 2001-2002, Marisol Caicedo Barrios Jan 2003

Determination Of Home Techniques For Storing And Conserving Food In The Homes Of Cuambo And La Rinconada In Imbabura Province, 2001-2002, Marisol Caicedo Barrios

Theses and Dissertations

In Ecuador, there is a grave socioeconomic nutritional problem, and it is seen clearest in Imbabura province in the communities of Cuambo and La Rinconada. One of the biggest problems is inadequate food, due principally to the poor food storage and conservation habits. Considering this problem, it is necessary to deepen the knowledge of improved traditional techniques for storing and conserving food, through which families can store and manage their product better, controlling and avoiding losses due to insects, rodents, and climate, and guaranteeing conservation of the same. The investigation was oriented to implement alternative, improved storage and conservation technologies …


Sedimentological And Plant Taphonomic Evaluation Of The Early Middle Devonian Trout Valley Formation, Jonathan Allen Jan 2003

Sedimentological And Plant Taphonomic Evaluation Of The Early Middle Devonian Trout Valley Formation, Jonathan Allen

Honors Theses

The Trout Valley Formation of Emsian-Eifelian age, outcropped in Baxter State Park, Maine, consists offluvial and coastal deposits preserving early land plants. Massive, crudely bedded conglomerate represents deposits of proximal braided channels on an alluvial fan complex. Lithic sandstone bodies in channel-form geometries represent deposits of river channels draining the Acadian highlands whereas associated siltstones represent overbank deposits, intertidal flats, and tidal channels. Localized lenticular quartz arenites represent nearshore shelf bar deposits that were storm influenced. The majority of plant assemblages preserved mainly in siltstone lithologies are allochthonous and parautochthonous, with only one autochthonous assemblage identified in the sequence. Plant …


Assessment Of Potential Environmental Impacts Of Nature-Based Tours Originating Within Clark County, Nevada, Beth Domowicz Jan 2003

Assessment Of Potential Environmental Impacts Of Nature-Based Tours Originating Within Clark County, Nevada, Beth Domowicz

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this thesis was to assess the potential magnitude of negative environmental damage of nature-based tours originating in Clark County, Nevada. An ordinal ranking system was used for assessment of five variables. These variables were resource use, noise pollution, soil degradation, vegetation degradation, and wildlife disturbance. There were two proposed answers. The first was that as distance increased, negative tour impact would increase. This was not supported, since tours had high impacts for destinations that were close by and far away. The second was that most tours were not causing high damage to the environment. This hypothesis was …


An Analysis Of Wetland Patterns And Functions At The Watershed And Sub-Watershed Scales, With *Policy Applications, Jennifer Newton Bissonnette Jan 2003

An Analysis Of Wetland Patterns And Functions At The Watershed And Sub-Watershed Scales, With *Policy Applications, Jennifer Newton Bissonnette

Dissertations, Theses, and Masters Projects

This dissertation addresses the need to define potential impacts of recent and proposed changes in federal wetland regulation in a quantifiable manner. Consideration was made not only of total wetland acreage and wetland types that could sustain losses, but also to categorize the effect such losses would have in terms of wetland functions, at the watershed scale. This work took a Geographic Information Systems (GIS) approach, and included employing a best-professional judgment model for scoring habitat, water quality and flood attenuation functions to determine potential cumulative impacts; a water quality study which related wetland and watershed variables to nutrient and …


Analysis Of Prey Selection In Black Skimmer, Rynchops Niger, Adults And Chicks Using Continuous Video Monitoring, Renae Joyce Held Jan 2003

Analysis Of Prey Selection In Black Skimmer, Rynchops Niger, Adults And Chicks Using Continuous Video Monitoring, Renae Joyce Held

Dissertations, Theses, and Masters Projects

No abstract provided.


Distribution, Abundance, And Home Range Of The Whip-Poor-Will (Caprimulgus Vociferus) In A Managed Forest Landscape, Michael Daniel Wilson Jan 2003

Distribution, Abundance, And Home Range Of The Whip-Poor-Will (Caprimulgus Vociferus) In A Managed Forest Landscape, Michael Daniel Wilson

Dissertations, Theses, and Masters Projects

No abstract provided.


Avian Communities Of Created And Natural Wetlands: Saltmarshes Of Southeast Virginia, David William Desrochers Jan 2003

Avian Communities Of Created And Natural Wetlands: Saltmarshes Of Southeast Virginia, David William Desrochers

Dissertations, Theses, and Masters Projects

No abstract provided.


Ecosystem Gas Exchange In Natural And Created Tidal Salt Marshes Of Tidewater, Virginia, Molly Mitchell Roggero Jan 2003

Ecosystem Gas Exchange In Natural And Created Tidal Salt Marshes Of Tidewater, Virginia, Molly Mitchell Roggero

Dissertations, Theses, and Masters Projects

No abstract provided.


Long Term Permanent Vegetation Plot Studies In The Matoaka Woods, Williamsburg, Virginia : Establishment And Initial Data Analysis Of Plots Established With The North Carolina Vegetation Survey Protocol, Resampling Of Single Circular Plots And A Comparison Of Results From North Carolina Vegetation Survey Protocol And Single Circular Plot Methods, Jacob Robert George Kribel Jan 2003

Long Term Permanent Vegetation Plot Studies In The Matoaka Woods, Williamsburg, Virginia : Establishment And Initial Data Analysis Of Plots Established With The North Carolina Vegetation Survey Protocol, Resampling Of Single Circular Plots And A Comparison Of Results From North Carolina Vegetation Survey Protocol And Single Circular Plot Methods, Jacob Robert George Kribel

Dissertations, Theses, and Masters Projects

No abstract provided.


Experimental Investigation Of Elemental Incorporation In The Otoliths Of Larval And Juvenile Fish: Implications For Use As Environmental Recorders, Gretchen Bath Martin Jan 2003

Experimental Investigation Of Elemental Incorporation In The Otoliths Of Larval And Juvenile Fish: Implications For Use As Environmental Recorders, Gretchen Bath Martin

Biological Sciences Theses & Dissertations

Innovative techniques for discerning fish stocks, identifying nursery habitats, locating spawning sites, tracing larval transport pathways, and quantifying the degree of population connectivity are required to meet the goals of sustainable management of marine capture fisheries. One of the most promising techniques is the use of elemental signatures in fish otoliths (ear stones), which record valuable life history data and serve as the link between fish and their environment. To validate the assumption that otolith elemental composition is a function of water elemental concentrations, and to address the possible effects of external variables such as temperature and salinity, the composition …


Use Of Ponds And Lakes By Resident Canada Geese, Phillip D. West Jan 2003

Use Of Ponds And Lakes By Resident Canada Geese, Phillip D. West

Dissertations, Theses, and Masters Projects

No abstract provided.