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Ecology and Evolutionary Biology

2003

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Articles 31 - 46 of 46

Full-Text Articles in Physical Sciences and Mathematics

Linear And Nonlinear Effects Of Habitat Structure On Composition And Abundance In The Macroinvertebrate Community Of A Large River, Timothy W. Stewart, Tammy L. Shumaker, Thomas A. Radzio Jan 2003

Linear And Nonlinear Effects Of Habitat Structure On Composition And Abundance In The Macroinvertebrate Community Of A Large River, Timothy W. Stewart, Tammy L. Shumaker, Thomas A. Radzio

Timothy W. Stewart

We used an experiment and regression analyses to quantify effects of spatial variation in habitat structure abundance on a riverine macroinvertebrate community under winter conditions. Concrete slabs (0.21 m2; n 5 24) with different numbers of stones (mean individual stone surface area 5 6.44 cm2) attached to upper faces were placed in the James River and retrieved after 28 d. Macroinvertebrate abundance and taxonomic richness on slabs were significantly positively related to stone abundance. Total macroinvertebrate abundance and abundance of oligochaetes (Nais spp.), Asiatic clams (Corbicula fluminea), caddisflies (Leptoceridae), riffle beetles (Elmidae) and stoneflies (Strophopteryx sp.) were linearly related to …

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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 …

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Water Quality Characterization And Mathematical Modeling Of Dissolved Oxygen In The East And West Ponds, Jamaica Bay Wildlife Refuge, Krishnanand Maillacheruvu, D Roy, John Tanacredi Ph.D. Jan 2003

Water Quality Characterization And Mathematical Modeling Of Dissolved Oxygen In The East And West Ponds, Jamaica Bay Wildlife Refuge, Krishnanand Maillacheruvu, D Roy, John Tanacredi Ph.D.

Faculty Works: CERCOM

The current study was undertaken to characterize the East and West Ponds and develop a mathematical model of the effects of nutrient and BOD loading on dissolved oxygen (DO) concentrations in these ponds. The model predicted that both ponds will recover adequately given the average expected range of nutrient and BOD loading due to waste from surface runoff and migratory birds. The predicted dissolved oxygen levels in both ponds were greater than 5.0 mg/L, and were supported by DO levels in the field which were typically above 5.0 mg/L during the period of this study. The model predicted a steady-state …

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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.

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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.

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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.

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Fishes Of The Red River In Arkansas, Thomas M. Buchanan, Drew Wilson, L. G. Claybrook, William G. Layher Jan 2003

Fishes Of The Red River In Arkansas, Thomas M. Buchanan, Drew Wilson, L. G. Claybrook, William G. Layher

Journal of the Arkansas Academy of Science

Fishes were collected from Red River mainstem habitats in Arkansas with seines, rotenone, hoop nets, gill nets, and trotlines from 1995 through 2001. Seventy-two species were identified distributed among 17 families, and 15 species were new records for the Red River in Arkansas. Eighty-three species are now historically known from the Arkansas segment of the Red River. Approximately 67% of the fishes known from the entire Red River have been found in the Arkansas segment, which is only 11% of the entire river length. Baseline data on the fish fauna of the Red River is critical for the analysis of …

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Acoustic Mapping Of Aquatic Vegetation In Lakes: An Example From Northwest Arkansas, Angela M. Polly, Stephen K. Boss Jan 2003

Acoustic Mapping Of Aquatic Vegetation In Lakes: An Example From Northwest Arkansas, Angela M. Polly, Stephen K. Boss

Journal of the Arkansas Academy of Science

No abstract provided.

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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.

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The Chesapeake Bay : A Synopsis, William J. Hargis Jr. Jan 2003

The Chesapeake Bay : A Synopsis, William J. Hargis Jr.

Reports

No abstract provided.

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12,000-Year Record Of Lake-Level And Vegetative Change At Mathews Pond, Piscataquis County, Maine, Usa, Andrea Masterman Nurse Jan 2003

12,000-Year Record Of Lake-Level And Vegetative Change At Mathews Pond, Piscataquis County, Maine, Usa, Andrea Masterman Nurse

Electronic Theses and Dissertations

This study of late-glacial and Holocene changes in lake-level and vegetation at Mathews Pond contributes new information about Holocene environments in northeastern North America. The research establishes a 12,000-year record of paleohydrology for the watershed adjacent to Big Reed Forest Reserve, the largest stand of old-growth forest in the northeastern United States. Mathews Pond is a 7.4 ha, closed-basin, groundwaterseepage lake located in an upland, forested region of the Aroostook River drainage system. Glacial meltwater briefly filled the basin - 13.0 ka (1 ka = 1000 I4C yr BP)). The lake existed as a shallow pool in the deep area …

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Extracellular Enzyme Activity And Uptake Of Carbon And Nitrogen Along An Estuarine Salinity And Nutrient Gradient, Margaret R. Mulholland, Cindy Lee, Patricia M. Gilbert Jan 2003

Extracellular Enzyme Activity And Uptake Of Carbon And Nitrogen Along An Estuarine Salinity And Nutrient Gradient, Margaret R. Mulholland, Cindy Lee, Patricia M. Gilbert

OES Faculty Publications

Amino acid oxidation (AAO) and peptide hydrolysis (PH) are processes affecting the recycling of organic material and nutrients. We compared extracellular AAO and PH rates to C and N uptake rates along estuarine gradients of salinity, nutrients and productivity in the Pocomoke River, a subestuary of the Chesapeake Bay. This estuary is seasonally depleted in inorganic N, and rich in dissolved organic material (DOM) throughout the year. AAO, PH, and N uptake rates measured in 1999 and 2000 were not limited to particular size fractions measured, or to auto- or heterotrophic groups of organisms. At a station near the turbidity …

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A Theoretical And Experimental Study Of Allee Effects, Joanna Gascoigne Jan 2003

A Theoretical And Experimental Study Of Allee Effects, Joanna Gascoigne

Dissertations, Theses, and Masters Projects

Allee effects occur when fitness suffers at low population size or density. This can lead to reduced population growth rate and a critical density below which extinction occurs. Allee effects can occur in reproduction or survival. Critical densities are higher in reproductive Allee effects than in juvenile survival Allee effects, making reproductive Allee effects more severe (higher extinction probability). In terms of the critical Allee effect threshold, reproductive Allee effects are more severe in r-selected populations, while juvenile survival Allee effects are more severe in K-selected populations. For populations with negative density dependence, there is a maximum critical Allee threshold, …

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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 …

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Recognizing Toxic Species In Aquatic Habitats: A Potential Concern In Lake Management, Mikolaj Kokocinski, Harold G. Marshall Jan 2003

Recognizing Toxic Species In Aquatic Habitats: A Potential Concern In Lake Management, Mikolaj Kokocinski, Harold G. Marshall

Biological Sciences Faculty Publications

The importance of distinguishing toxic and non-toxic algal species is becoming a more common problem for management decisions associated with various freshwater and estuarine habitats. An example is given where two dinoflagellates, originally unidentified as closely resembling the toxin producing Pfiesteria spp., have been compared to these species. In order to clarify any relationship to Pfiesteria spp., scanning electron microscopy was used to determine the plate tabulation patterns of these dinoflagellates and make comparisons to the tabulation present in Pfiesteria spp. The results indicated significant differences in the plate tabulations of these taxa to distinguish them from Pfiesteria …

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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 …

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