• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 91
  • 11
  • 6
  • 3
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 124
  • 124
  • 19
  • 16
  • 15
  • 14
  • 13
  • 11
  • 11
  • 10
  • 9
  • 9
  • 9
  • 8
  • 8
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Select geomorphological components of wildlife habitat in the ridge and valley province of Virginia

Martin, Steven M. 20 November 2012 (has links)
I examined geomorphology as it relates to wildlife and wildlife habitat I sought to make dimensions of land surface shape (terrain) available for use by natural resource professionals. Most geomorphic processes operate on longer time scales than the life spans of organisms that inhabit a landscape. So, it is the shape of the land surface, not formative processes that are considered in most environmental sciences. Terrain molds and is molded by climate, vegetation, and geology. Terrain influences site-specific temperature, precipitation, solar radiation, and winds. Through these climatic effects, terrain influences the distribution of plant species and plant phenologies. I examined the role of terrain in applied environmental sciences including forestry, soil science, hydrology, and fisheries. Terrain also affects the distribution, movements, energetics, cover, and food habits of wildlife species. I identified 8 parameters of land surface shape: elevation, slope, aspect, relief, length, area, roughness and texture, pattern and shape. From physical science literature, I identified over 120 descriptors of surface shape that measure 1 or more of these parameters. Through an objective-weighting procedure, I selected 60 descriptors to include in a computer-based system for quantifying land surface shape. The resulting system, GEODES, integrates a raster-based GIS, vector mapping programs, and a relational data base management system to present these land surface shape descriptors. Specific applications of individual descriptors and of GEODES are suggested. Individual descriptors or the larger system (GEODES) may be used to reduce variance in wildlife research and management, and to increase managerial control. / Master of Science
72

SUMMER HABITAT USE BY MOUNTAIN SHEEP.

Gionfriddo, James P. January 1984 (has links)
No description available.
73

Ecology of the Merriam's wild turkey in north-central Arizona

Crites, Mark Jeffrey, 1957- January 1988 (has links)
Information on the ecology of radio-equipped Merriam's wild turkey hens was recorded from 1982-1985 in north-central Arizona. The average net direct line distance that the hens moved was 16.0 miles (25.8 km). Over 35% of the adult hens and 70% of the juvenile hens died during the study, with the majority dying during the winter months. Fifty-four percent of the hens (25% of the juveniles) alive during the nesting season nested, with 54% of those (100% of the juveniles) successfully bringing a brood off the nest. Cover at twelve nests sampled was higher than the surrounding areas, being supplied by oak thickets, slash, and conifers. Successful nests had more cover at the site and more cover in the surrounding areas than the unsuccessful nests. Three broods followed used different combinations of stand types, depending on habitat and food availability.
74

Conception and Design of Constructed Wetland Systems to Treat Wastewater at the Biosphere 2 Center with Use of Reaction Rate Models and the Habitat Evaluation Procedure to Determine the Effects of Designing for Wildlife Habitat on Treatment Efficiency

Clingenpeel, Glenn C. (Glenn Christopher) 05 1900 (has links)
A study was undertaken to explore relationships between wetland characteristics which make them efficient water purifiers versus their ability to serve as wildlife habitat. The effects of designing constructed wetlands for improved habitat on water treatment efficiencies were quantified. Results indicate that some sacrifice in treatment efficiency is required and that the degree of efficiency reduction is dependant upon pollutant loading rates. However, sacrifice in efficiency is much smaller than increase in habitat quality, and can be offset by increasing wetland area. A practical, theoretical application was then attempted.
75

Impact of elephant induced vegetation change on the status of the bushbuck (Tragelaphus scriptus ornatus) along the Chobe river in Northern Botswana

Addy, Joanne Estelle 24 June 2015 (has links)
Thesis (M.Sc.)--University of the Witwatersrand, Faculty of Science, 1993.
76

Habitat location and selection by the Sargassum crab Portunus sayi: the role of sensory cues

Unknown Date (has links)
The Sargassum community consists of a unique and idverse assemblage of fauna critical to pelagic food chains. Associated organisms presumably have adaptations to assist in finding Sargassum. This study investigated cues used for habitat location and selection by the Sargassum crab, Portunus sayi. Chemical detection trials were conducted with a two-chamber choice apparatus with Sargassum spp. and Thalassia testudinum as source odors. Visual detection trials (devoid of chemical cues) and habitat selection trials were conducted in which crabs were given a choice of habitats. Results showed that P. sayi respoded to chemical odors from Sargassum spp. Crabs visually located habitats but did not visually distinguish between different habitats. In habitat selection trials, crabs selected Sargassum spp. over artificial Sargassum and T. testudinum. These results suggest that crabs isolated from Sargassum likely use chemoreception from longer distances ; within visual proximity of a potential patch, crabs use both chemical and visual information. / by Lorin E. West. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
77

The Role of Chemical Cues in Locating Pelagic Sargassum by the Associated Fish Stephanolepis hispidus

Unknown Date (has links)
The ecosystem created by pelagic Sargassum is important in the life histories of a number of economically and ecologically important associated organisms. Fishes play a vital role in this food web and nutrient flow within these systems, but it is unknown how they locate these floating habitats. This study examined the role of natural chemical cues from Sargassum patches and the synthetic chemical Dimethylsulfonionpropionate (DMSP) for an associated fish, the planehead filefish (Stephanolepis hispidus) and a control fish species not associated with Sargassum, the masked goby (Coryphopterus personatus). Choice trials with a Y-maze apparatus determined that S. hispidus responded significantly to chemical cues from Sargassum while C. personatus did not. DMSP cues did not result in any significant behavioral responses for either fish. Demonstrating that S. hispidus can respond to chemical cues from Sargassum helps further our understanding of this unique floating algal reef and how fishes may locate it. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
78

Response of ant communities to vegetation clearing and habitat fragmentation in Central Queensland

Schneider, Kathryn Erica January 2004 (has links)
Habitat fragmentation involves the break-up of continuous native vegetation into remnant patches that are set in a matrix of altered habitat. The consequences of habitat fragmentation include the loss of original habitat which is followed by reductions in remnant size that increase edge effects and reduce habitat quality, and also increase the isolation of remnants from one another. Habitat fragmentation is an international environmental concern that also effects Australia. Over the last ten years Queensland has been responsible for some ninety percent of the clearing occurring in Australia, and as a result recorded some of the highest vegetation clearing rates in the world. / thesis (PhDEnvironmentalManagement)--University of South Australia, 2004.
79

The use of primary producers for assessing and monitoring aquatic habitat quality in Great Lakes coastal wetlands

McNair, Sheila A. Chow-Fraser, Patricia. January 2006 (has links)
Thesis (Ph.D.)--McMaster University, 2006. / Supervisor: Patricia Chow-Fraser. Includes bibliographical references.
80

Response of ant communities to vegetation clearing and habitat fragmentation in Central Queensland

Schneider, Kathryn Erica January 2004 (has links)
Habitat fragmentation involves the break-up of continuous native vegetation into remnant patches that are set in a matrix of altered habitat. The consequences of habitat fragmentation include the loss of original habitat which is followed by reductions in remnant size that increase edge effects and reduce habitat quality, and also increase the isolation of remnants from one another. Habitat fragmentation is an international environmental concern that also effects Australia. Over the last ten years Queensland has been responsible for some ninety percent of the clearing occurring in Australia, and as a result recorded some of the highest vegetation clearing rates in the world. / thesis (PhDEnvironmentalManagement)--University of South Australia, 2004.

Page generated in 0.0335 seconds