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  • 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.
31

The effects of prescribed burning on deer and elk habitat parameters in Montana's Missouri River Breaks

Wood, Christopher Karl. January 2004 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2004. / Typescript. Chairperson, Graduate Committee: Clayton B. Marlow. Includes bibliographical references (p. 49-53).
32

Use of Landsat Imagery and Geographical Information Systems in the Assessment of Rangeland Cover and Wildlife Habitat

Hunnicutt, Mary 01 January 1992 (has links)
The first chapter of this thesis reviews applications of satellite remote sensing and geographical information systems (GIS) in wildlife studies. The simpler uses of remote sensing are for habitat mapping, often using satellite imagery classified for other natural resources. More sophisticated applications incorporate remotely sensed data into a GIS for the digital manipulation of data planes. The most advanced applications are those which use remote sensing and GIS in models predicting habitat quality or population levels. The second chapter reports how brightness values of six Landsat Thematic Mapper (TM) bands were used in multiple linear regressions to predict percent cover of six rangeland components. Regression equations were applied to TM imagery to create cover maps for live shrub, dead and live shrub, sagebrush, forb/grass, forb, and bare ground/rock. Accuracy was assessed at two levels and ranged from 55 to 90%. The third chapter presents results of sage grouse surveys used with satellite data and GIS to assess habitat use patterns. Habitats used by grouse were compared to availability in the landscape for continuous images of rangeland cover variables, for discrete images of rangeland classes, and for habitat diversity values. Overall, results were comparable to those in studies using traditional methods.
33

Wildlife management on Virginia Conservation Reserve Program land: the farmer's view

Miller, Edwin Joseph January 1989 (has links)
M.S.
34

Salt marsh creation and coastal residential developments: principles and guidelines for landscape architecture practice

Murata, Masatomo 13 February 2009 (has links)
Salt marsh creation provides functions and values that are essential to maintain the welfare of people and the integrity of coastal area ecosystems. The literature review provides greater understanding of salt marsh functions and values technical information regarding wetland creation in coastal regions. Interviews and case study analyses identify issues and opportunities regarding salt marsh creation. Products of this study include a model approach, criteria for project evaluation, and principles and guidelines for salt marsh creation and coastal residential development. Model approach applies the technical information and processes of salt marsh creation provided by scientists and engineers to the landscape architecture design process. The model approach encourages involvement of the client and other professionals throughout the planning and design process. The proposed criteria provide a framework for landscape architects to evaluate the structure and function of created ecosystems and developments. Four salt marsh creation projects around the Chesapeake Bay were selected for review and evaluated according to these criteria. Each project provides evidence that salt marsh creation can benefit residential developments by providing long-term shoreline protection, water purification, wildlife habitat, and amenity of a naturalistic landscape. Design principles and guidelines will help ensure that the model approach is used by developers to attain salt marsh creation that fits the patterns and functions of surrounding ecological systems and increases residents' awareness of both functions and values of salt marsh and the larger. / Master of Landscape Architecture
35

The effects of chronic low-dose radiation on bumblebees

Raines, Katherine Elizabeth January 2018 (has links)
The consequences to wildlife of living in contaminated areas with chronic low-dose rates of radiation are still relatively unknown. Laboratory studies using acute radiation have demonstrated that invertebrates are relatively radioresistant compared to other taxa. However, there is little scientific evidence to show how chronic low dose rates affect invertebrates. This is problematic for understanding the consequences to wildlife living in highly contaminated areas and also testing assumptions made for invertebrates by the International Commission on Radiological Protection (ICRP). This thesis was designed to address a number of recommendations have been suggested to improve radioecological studies and help reduce the uncertainty as to effects at low dose rates. These include environmentally relevant laboratory studies (Chapters 2 and 4), improved dosimetry and dose assessments (Chapter 3), investgating confounding factors (Chapter 4) and continuity between laboratory experiments and field work conducted in the Chernobyl Exclusion Zone (CEZ) (Chapter4). Chapter 2 presents an environmentally-relevant experiment testing how bumblebee reproduction and life history is affected by chronic low-dose rates. Unexpectedly, at dose rates equivalent to the CEZ, queen production declined and reproductive timing was altered. The estimation of dose rates to establish a dose-effect relationship for wild animals is difficult and a common criticism of radioecological studies, therefore, Chapter 3 tests whether the common approach to measuring only external ambient dose rates is suitable and whether the inclusion of life-history traits significantly alters the dose rate. The findings from this chapter reiterate the necessity to use dose-assessment tools to test different parameters to estimate dose rate in different scenarios to account for unknown variation. Chapter 4 demonstrates that in areas of elevated dose rates in the CEZ parasite burden was higher and bumblebees did not live as long. These results were reinforced by a laboratory study, which determined bumblebees exposed to increased radiation doses had high parasite burdens and were infected quicker, resulting in reduced longevity. The data in this thesis detected effects below the current dose bands used in international radioprotection and therefore advocate these dose bands be re-evaluated. However, the data do not support studies which have measured adverse effects at dose rates similar to background and suggest that confounding factors such as habitat quality and co-stressors need to be included in field and laboratory studies.
36

Assessment of Resource Selection Using Remote Sensing and Geographic Information Systems (GIS) for Two Vertebrates in Disparate Habitats: the Gopher Tortoise (<em>Gopherus Polyphemus</em>) and the North Atlantic Right Whale (<em>Eubalaena Glacialis</em>)

Keller, Cherie A 13 July 2005 (has links)
This dissertation is a treatise on spatially-explicit resource selection on two very different vertebrate species. The North Atlantic right whale (Eubalaena glacialis) is the most endangered large whales in the world. Ship strikes and fishing gear entanglement are impediments to recovery. The gopher tortoise (Gopherus polyphemus) is an imperiled species whose upland habitats are shrinking from urban and agricultural development. Determining spatial distribution of important resources is important for conservation strategies. Historical and modern thinking of habitat selection theory and analytical techniques are reviewed and applied to these species. Fine-scale resource selection of sea surface temperature (SST), derived from AVHRR imagery, is evaluated for right whales in the southeastern U. S. calving grounds. Aerial survey data (December-March, 1991-1998) including survey tracklines and right whale locations were entered into a Geographic Information Systems (GIS) for comparing whale use of SST to availability based on search effort. Using Monte Carlo techniques, mean and standard deviation for SSTs and latitudes of whale-sightings were compared to sampling distributions derived from available SSTs and latitudes. From these data, it was concluded that the North Atlantic right whale uses SSTs and latitudes non-randomly. Broad-scale habitat selection for gopher tortoises was evaluated from the 2003 Land Cover/Land Use map (Florida Fish and Wildlife Conservation Commission). Based on land cover and ancillary data, potential gopher tortoise habitat was developed for northeast Florida.
37

Effects of five different intensities of stand establishment on wildlife habitat quality and tree growth in loblolly pine (Pinus taeda) plantations in southern Mississippi

Jones, Phillip Daniel, January 2008 (has links)
Thesis (Ph.D.)--Mississippi State University. Department of Wildlife and Fisheries. / Title from title screen. Includes bibliographical references.
38

Behavioural ecology of duikers (Cephalophus spp.) in forest and secondary growth, Tai, Cote d'Ivoire

Newing, Helen S. January 1994 (has links)
The behavioural ecology of duikers (Cephalophus spp.) was studied in mature forest and mixed secondary vegetation around TaI National Park, Cöte d'Ivoire. The most common species in both vegetation types was C. maxwelli, followed by C. dorsalis, C. ogilbyi, C. niger, C. zebra and C. lentinki in mature forest, and C. niger, C. dorsalis and C. sylvicultor in secondary vegetation. Population surveys were carried out by a number of methods. Transect censuses by night were found most efficient in mature forest, whereas in secondary vegetation, only pellet transect censuses and drives into nets were possible. C. maxwelli populations were estimated at about 63 km2 in mature forest and 79 km2 in secondary vegetation. Duikers were primarily frugivorous, but the proportion of leaves taken increased in the season of fruit scarcity. Fruit abundance in different habitats increased with the age of the vegetation. Six C. maxwelli in mature forest and four in secondary vegetation were radio-collared to determine ranging patterns and social behaviour. They were diurnal and lived in groups of one male with one or two females and young. Home ranges, which were about 5 ha in size in mature forest and 3.6 ha in secondary vegetation, were defended by males, and the boundaries were marked by latrine areas by both sexes. In mixed secondary vegetation, all habitats were used except open fields and bamboo thickets. Implications for conservation and management are discussed. The continued preservation of mature forest and the control of poaching are essential for the survival of the three rarer species (C. -jentinki, C. zebra and C. ogilbyi). The control of poaching must precede any programme of sustainable harvesting of the more abundant species, which could be carried out in secondary vegetation. Duiker farming may be possible if low-cost sources of fencing and forage can be identified.
39

Simulating Disturbance Impact on Wildlife with Agent-based Modeling Approach: A Study of Tropical Peatland Fire and Orangutan Habitat

Widyastuti, Kirana 28 June 2023 (has links)
Ecosystem disturbances are a significant and ongoing threat to wildlife, caused by both natural environmental changes and human impacts. These disturbances can have a range of impacts, but one of the most crucial is on the wildlife habitat. In tropical forests, one such disturbance that is occurring at an alarming rate is peat fires. Peatfires impact the forest structure and fragmentation, which in turn directly relate to the wildlife habitat, ultimately threatening the population and even risking extinction for certain species. Of particular concern is the population of orangutans in Indonesia, which is at risk due to the impact of peat fires. This research used an agent-based modelling approach to explore the impact of ecosystem disturbances on wildlife habitat. The focus was on the orangutan population in tropical forests affected by peat fires. A systematic review of agent-based models revealed a shift towards a more mechanistic representation of entities in wildlife response to disturbances. However, fire disturbances and primate species such as orangutans still have a limited number of models. To address this gap, two agent-based models are presented: PeatFire, a model of the ignition and spread of tropical peatfire, validated using data from a fire pattern in South Sumatra; and the BORNEO model, which simulates the movement behaviour of orangutans in a disturbed forest using real tree inventory data and orangutan tracking data from the Sebangau forest in Central Kalimantan. The models were calibrated and validated using state-of-the-art methods and high-performance computing. The study demonstrates the ability of ABM to tackle complex research problems in various fields, including wildlife response to disturbances. The models developed in this study are important examples of the shift towards a more mechanistic representation of agents in ABM, and contribute to advancing the field in this direction. The research offers insights into the impact of ecosystem disturbances on wildlife habitat and highlights the potential of ABM in addressing these issues.
40

An ecological study of forest clearings on the Big Levels Game Refuge

Thornton, James E. January 1940 (has links)
Master of Science

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