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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.
251

Social network analysis of stakeholders in the Duiwenhoks Water Catchment

Whyte, Michelle January 2013 (has links)
Social-ecological systems are facing complex social, political, economic and environmental problems beyond the capacity of one group of stakeholders or organization to solve in isolation. Ecosystem degradation causes major environmental and economic concern, due to the loss of ecosystem services which river and wetland ecosystems provide. Stakeholder communities who depend on natural resources need to identify the social processes which are underlying causes to unsuccessful natural resource management and thus environmental degradation. The study is primarily aimed at identifying and understanding the structural and functional properties of the stakeholder network in the Duiwenhoks River catchment in the Western Cape, South Africa. Through analyzing the social network properties the study identifies and describes the main stakeholders involved with natural resource management in the Duiwenhoks water catchment area. How the individual actors from the diverse stakeholder groups are connected through communication ties were assessed. Furthermore, issues and factors which limit the effectiveness of the social network were identified. The main factors include a lack of communication and collaboration between key local resource users and governance officials caused by conflicting perspectives regarding resource management and societal conflicts caused by asymmetries in power distribution favoring government institutions. The lack of collaboration between stakeholders was identified as a contributing factor that links to the resource degradation experienced in the catchment. Ultimately means of overcoming the limitations to effective social networking, in order to manage the challenges related to natural resource management were identified. Management recommendations include the development of bridging ties and collaboration between diverse stakeholders, whilst facilitating participatory processes aimed at participatory problem solving and adaptive co-management of natural resources. Government institutions were identified as being dominant stakeholders in the network and should be mobilized to perform a stronger bridging role to connect disconnected actors. The findings of the study may inform future efforts of researchers and facilitators to implement strategies which promote social networking, social learning and ultimately adaptive co-management in the study area or other similar social-ecological systems. Ultimately, collaboration can be achieved between the diverse stakeholders to successfully improve ecosystem management and resilience in the Duiwenhoks water catchment.
252

Flagship species, tourism, and support for Rubondo Island National Park, Tanzania

Stevens, Sadie S 01 January 2011 (has links)
Two major goals of managers of Rubondo Island National Park (Rubondo), Tanzania are to increase the number of international visitors to the Park (and thereby increase revenue generated) and to increase support for the Park among residents of nearby communities. I investigated species preferences among children living around Rubondo and the wildlife viewing preferences of international visitors to Tanzania in an attempt to identify flagship species that Park management could use in marketing and outreach campaigns designed to meet their goals. I also assessed local interest in visiting the Park. As local flagships for Rubondo, the Egyptian goose (Alopochen aegyptiacus ) and silver cyprinid (Rastrineobola argentea) appear to have the most potential among the species that I assessed (i.e., fish eagle [Haliaeetus vocifer], Egyptian goose, silver cyprinid, little egret [Egretta garzetta], sitatunga [Tragelaphus speki], genet [Genetta tigrina], monitor lizard [Varanus niloticus], spotted-necked otter [Lutra maculicollis], vervet monkey [Cercopithecus pygerythrus], crocodile [Crocodylus niloticus], hippopotamus [ Hippopotamus amphibius], giraffe [Giraffa camelopardalis ], and elephant [Loxodanta africana]). However, based on either range or limited aesthetic/behavioral appeal, I considered neither species useful as an international flagship. Among species on Rubondo included in investigations of potential international flagships for the Island (including the chimpanzee [Pan troglodytes], crocodile, elephant, giraffe, hippopotamus, vervet monkey, bushbuck, fish eagle, large-spotted genet, goliath heron [Ardea goliath], monitor lizard, sitatunga, and spotted-necked otter), few were concluded to have potential, either because participating visitors had limited "awareness" of and "interest" in viewing the species, local people had strong negative opinions of the species, the animals are not native to the Island, and/or the animals are more easily viewed in more readily-accessible locations. Local people generally had not visited Rubondo but wanted to visit. Not having visited the Park appeared to influence perceptions of the Park, wildlife tourism, and conservation among some participants. Recommendations for local and international marketing and outreach strategies for Rubondo are made based on the outcomes of the aforementioned investigations of local and international species preferences and interest in visiting the Park.
253

Conservation ecology of the Cape clawless otter, Aonyx capensis, in an urban environment

Okes, Nicola Catherine January 2017 (has links)
Coastal cities have impacted negatively on freshwater and marine ecosystems - primarily through habitat loss, fragmentation and pollution. Globally, it has been found that otter's dependence on these ecosystems exposes them to a myriad of threats, including loss of habitat, human-wildlife conflict and the bioaccumulation of toxic pollutants. The Cape clawless otter, Aonyx capensis, is the most widely distributed otter species in southern Africa and persists in human-modified habitats, including large cities. The Cape Peninsula provides a unique opportunity to study the impacts of urbanisation on otters as it presents a gradient from densely populated urban areas in the north (City of Cape Town) to sparsely populated areas interspersed with large expanses of natural habitat (Table Mountain National Park) in the south. In this thesis, I investigate the distribution, diet and threats to otters living on the Cape Peninsula. I use sign-based occupancy surveys to determine both broad and fine scale drivers of otter presence within the Peninsula's river systems and predicted that otters would avoid densely populated urban areas and rivers or sections thereof that are heavily transformed and polluted. I collected spraint from living otters and vibrissae from dead otters to investigate their diet. I predicted that otters would show an increased reliance on marine foods in areas where freshwater habitats were degraded in addition to seasonal variation in diet associated with the marked seasonal variation in rainfall and primary productivity typical of temperate Mediterranean ecosystems. I explored both immediate and long-term threats to otters by collating all records of conflict, injury and mortality reported over 5 years in addition to determining PCB levels from road-killed otters. Contrary to my predictions, otters did not avoid urban areas, and were more frequently detected in transformed lowland freshwater river systems close to Marine Protected Areas (MPA). Within rivers otters avoided the relatively pristine, yet unproductive, upper reaches of rivers as well as canalised sections and those with consistently high E.coli counts. I found that otters were feeding on both marine and freshwater prey in both polluted and nonpolluted systems. Where large, transformed lowland wetlands were in close proximity to MPAs, otter diet consisted largely of a combination of freshwater crabs and exotic fish from the polluted systems as well as marine fish and rock lobster from the relatively unpolluted MPA. Isotope results complemented the faecal analyses and confirmed that otters show significant variation in diet between seasons, sites and individuals, suggesting an opportunistic and generalist foraging strategy. Importantly, the dietary results reinforce the distribution model that otters rely heavily on the interface between coastal and lowland wetland and river ecosystems close to the MPA, for both foraging and breeding habitat. However, these are the areas that are transformed and heavily impacted by urban development, and therefore the area where otters would most likely be at risk. I developed a hotspot map of otter conflict across the Peninsula and found that the Peninsula otter population experiences low to moderate levels of conflict throughout most of their current range. High conflict areas are associated with optimal habitat that has been fragmented by canalisation and urban development. Road-killed otters showed signs of accumulation of PCBs in liver tissue suggesting that despite otters being adaptable generalists, their dependence on polluted freshwater systems may have long-term health impacts. Mitigating these threats is possible with improved urban planning, waste water treatment and education of the public. However the success of these approaches requires long-term monitoring which is unlikely to be prioritised by resource constrained conservation authorities. I thus explored whether the large citizen science community in Cape Town can be used to monitor the population. I used Maxent to model otter distribution using citizen reported sightings over 5 years and compared the results with the occupancy model outputs. The predicted Maxent distribution mirrored that provided by occupancy models, and highlighted further areas of suitable otter habitat and routes for dispersal. Together my findings suggest that Cape clawless otters, like many other meso-carnivores in South Africa and globally, display a remarkable ability to adapt to human-modified environments using the interface between degraded freshwater systems and the inshore region to feed on a diverse range of prey. Of concern are the moderate to high levels of conflict with people and dogs, vehicle accidents and the accumulation of toxins. Long-term monitoring of the population and the effect of proposed interventions can be achieved by creating a platform for citizen sightings to be recorded in perpetuity at low cost. This platform can also serve as tool for educating the public on the global challenges of conserving biodiversity within and adjacent to large cities.
254

Issues of modern botanical conservation and methodology for the effective assessment of plant extinction risk

Sagatelova, Maria January 2021 (has links)
No description available.
255

The ecology and management of the Kaapsehoop cycad (Encephalartos laevifolius Stapf and Burtt Davy)

Zunckel, Kevan January 1990 (has links)
Bibliography: p. 182-190. / The Kaapsehoop Cycad (Encephalartos laevifolius Stapf and Burtt Davy) has the international, national, and provincial status of "endangered" by virtue of a number of factors which threaten it with extinction. It occurs in only three disjunct populations in southern Africa, of which two are very small and have only adult plants. This situation suggested the need for specific action to ensure the conservation of the plant within its natural habitat. This study was initiated in an attempt to respond to this call for action. The aims of the study were set at gaining an understanding of the ecology of the cycad, establishing the exact nature and extent of the factors threatening it with extinction, and presenting management guidelines as to how the plant and its habitat may be managed to ensure their conservation. Chapter One includes a background to the botanical significance of cycads in general, the reasons for the endangered status of E. laevifolius and a list of aims and objectives. The latter are briefly; to develop. an understanding of the ecology of this cycad, determine the nature and extent of the threats which have placed it in the ''endangered" category, and establish means of managing the plants and their habitat so as to mitigate these threats . The methodology followed to achieve the latter is presented in Chapter Two. The results achieved from work carried out by the author are presented In Chapter Three, and they are then discussed in Chapter Four, together with those obtained from other researchers and experts in the field of cycad ecology and management. From this it becomes apparent that the major factor threatening the plants continued existence in nature, is its illegal removal by unscrupulous collectors. The use of fire as a management tool may cause the loss of sexually propagated off-spring if not based on ecological principals. This would be tragic as the percentage of fertile seed being produced at present is extremely low. Besides the latter two abiotic threats, there are two biotic threats which are also .cause for concern. They are the rotting of the female cones and seed by a pathogenic infection, and the destruction of newly growing tissue by the caterpillars of the Leopard Moth. The insights gained from the study are drawn together as conclusions in Chapter Five. Where these indicate specific management measures or directions for further research, recommendations are made. It must be emphasized that although this study has been used for the enhancement of the author's academic qualification, it is vitally important that the recommendations made be seriously reviewed by those responsible for the conservation of this cycad. If this study is simply put on the shelf after it has achieved its academic goal, the possibility of E. laevifolius becoming extinct is very real.
256

Constraints on soil conservation in the Pindars River and Two Meetings Watersheds, Jamaica

Wigley, Georgina M. January 1988 (has links)
No description available.
257

Ecology and conservation of Sumatran elephants (Elephas maximus sumatranus) in Sumatra, Indonesia

Sitompul, Arnold Feliciano 01 January 2011 (has links)
Sumatran elephant (Elephas maximus sumatranus) continue to decline due to habitat loss, poaching and conflict with humans. Yet, developing effective land conservation strategies for elephants is difficult because there is little information available on their foraging ecology, habitat use, movements and home range behaviors. Using the lead animal technique, 14 free-ranging, tame elephants at the Seblat Elephant Conservation Center (ECC) were observed for 4,496 hours to describe their foraging ecology and diet. The majority of their daily activity was feeding (82.2 ± 5.0%), followed by moving (9.5 ± 4.0 %), resting (6.6 ± 2.1%) and drinking (1.7 ± 0.6%), and individual activity budgets varied among individuals for all activities. At least 273 plant species belonging to 69 plant families were eaten by elephants and five plant families of Moraceae, Arecaceae, Fabaceae, Poaceae, and Euphorbiaceae were most commonly consumed. Elephants browsed more frequently than grazed, especially in the wet season. Levels of crude protein, calcium, phosphorus and gross energy in plants eaten by elephants in Seblat appeared adequate for meeting the nutritional requirements. Home range size of an adult female elephant in the SECC during 2007–2008, was 97.4 km2 for the MCP and 95.0 km2 for the 95% fixed kernel. There were no relationships between average monthly elephant home range sizes or movement distances with rainfall. Distances to rivers and ex-logging roads had little effect on elephant movements, but vegetation productivity, as measured by the Enhanced Vegetation Index, did affect elephant movements. We used resource selection and compositional analysis habitat ranking approaches to describe adult female elephant habitat use in the SECC. The elephant used medium canopy and open canopy forests more than expected; however, during the day closed canopy forests were used more than at night. Locating and capturing wild elephants in tropical rainforest environments are difficult and high-risk tasks. However, using tame elephants improves the search efficiency of finding wild elephants in dense forests and reduces risks to staff and target elephants. Use of experienced veterinarians and standing sedation techniques also greatly reduce the risks of elephant injury while immobilizing elephants.
258

Understanding the terrestrial carnivore community composition and distribution in Southeastern Ohio

Rich, Mackenzie E. 04 September 2017 (has links)
No description available.
259

Likely Successors of Ash Species in Response to the Emerald Ash Borer in Ohio Forests

Good, Brian Michael 27 August 2013 (has links)
No description available.
260

EFFECTS OF AGRICULTURAL LAND CONVERSION AND LANDSCAPE CONNECTIVITY ON MOVEMENT, SURVIVAL, AND ABUNDANCE OF NORTHERN BOBWHITES (COLINUS VIRGINIANUS) IN OHIO

Smith, Olivia M. January 2015 (has links)
No description available.

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