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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.
281

Determining the Effects of Fire on Ridge Shape Complexity In the Central Everglades

Unknown Date (has links)
Self-organized spatial patterning of microtopographic features is a trademark characteristic of the Everglades landscape. Anthropogenic modifications to Everglades’ hydrology have reduced and degraded pattern, where ridges occur at higher elevations and spread into open water sloughs under dryer conditions. Wildfire is an important ecological force in the central Everglades and may maintain ridge-slough patterning through reducing ridge size and complexity, and thus preserve habitat heterogeneity. To investigate fire as a patterning mechanism in the central Everglades I examined the shape complexity and area distribution of ridges along a chronosequence of time since fire. Shape complexity did not change following fire, but small and large ridges became more prominent and eventually spread as time since fire increased, suggesting fire may maintain ridge area distribution. Documentation of fires’ effect on ridge size will inform ecosystem and conceptual models detailing the complex interactions that maintain the Everglades ridge-slough patterning. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
282

Faunal distribution in relation to rainfall patterns in the Kalahari Gemsbok National Park

Maraschin, Nicoletta Maria Rita January 2016 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, 2016. / This project investigates the influence that rainfall and temperature patterns have on mammal drinking patterns at an artificial waterhole in KGNP at Nossob. On a regional scale, this project investigates long-term rainfall and temperature trends over three/four decades, and in some instances the past 100 years, respectively for KGNP using climate records from weather stations located within the park and adjacent areas. This project makes use of KGNP census data to observe spatio-temporal distributions of large mammals in relation to rainfall (and to a lesser extent temperature) variability. Investigations assess whether relationships exist between faunal movement and distribution and rainfall volume and frequency. On a local scale, this project makes use of webcam images measured at 15-second intervals to establish mammalian drinking patterns and waterhole use over a short time scale (October 2012 – December 2014). The climate data for Twee Rivieren, Mata-Mata, Nossob and Upington reveal statistically significant increases in Tmax (av. 0.04°C) over the study period, whilst in summary, mean regional temperatures have increased by almost 1.6°C over the past 40 years. Rainfall patterns have revealed a north to south gradient in KGNP, where the northern and central parts of the park are becoming drier and the southern parts are becoming wetter. This demonstrates rainfall variability throughout KGNP over the period 2004 - 2013. This study established a positive relationship between faunal distributions and rainfall patterns within the park, showing that certain species are highly reliant on rainfall as a source of drinking water. It has been established that herbivore species are more reliant on the water trough during the dry season, when surface water is not available. However, there is an even spread of carnivore species water trough usage during the wet and dry season throughout the year. It has been established that during rainfall events exceeding ca. 30mm, faunal species prefer to utilise the natural surface water rather than the artificial waterhole at Nossob. Water trough usage under different temperature thresholds has revealed that groups of species (carnivores and herbivores) drinking patterns shift to either earlier or later in the day when temperatures increase, in order to avoid heat stress. Changing rainfall patterns could drastically cause water shortages, which will negatively affect the amount of available drinking water for mammals within KGNP. This study is important in contributing to an improved management of KGNP through providing a quantitative description of the relationship of mammal visitation at water troughs to the ambient climate. This is particularly valuable as climate change projections for the region suggest progressive drying. Water troughs will become an important source of moisture. / LG2017
283

Analysis of environmental stressors on ecosystems of Xuan Thuy National Park, Vietnam / Phân tích các mối đe dọa môi trường hệ sinh thái tại Vườn Quốc Gia Xuân Thủy, Việt Nam

Haneji, Choshin, Amemiya, Takashi, Itoh, Kiminori, Mochida, Yukira, Hoang, Thi Thanh Nhan, Pham, Van Cu 19 August 2015 (has links) (PDF)
Above-ground biomass was allometrically estimated to quantify the amount of mangrove species in selected quadrats of Xuan Thuy National Park. Physicochemical properties of surrounding waters and soils were measured and treated stochastically by correlational analysis with estimated biomass values. Correlation results suggested that qualities of surrounding waters and soils are not the principal inhibitors of mangrove growth in Xuan Thuy. The available historical records infer that the main factor of mangrove loss in the past lay on land reclamation for shrimp aquaculture. In addition, results of correlation analysis showed geographical coincidence of mangrove fragmentation with influence area of water channeling used for aquaculture activities. Furthermore, the distribution of anomalous values of metals concentration was corresponding with anthropological activities associated to clam aquaculture and sand extraction. Based on the aforementioned analysis and the information on anthropological activities in the buffer zone of Xuan Thuy, were provided basic information on inherent environmental stressors of ecosystems in Xuan Thuy National Park. / Sinh khối trên mặt đất đã được ước tính theo phương pháp tương quan sinh trưởng để đưa ra số lượng các loài đước trong các mẫu vuông được lựa chọn tại Vườn quốc gia Xuân Thủy. Các đặc tính hóa-lí của những vùng nước và đất xung quanh đã được đo đạc và xử lí ngẫu nhiên bằng cách phân tích tương quan với những giá trị sinh khối ước tính. Kết quả tương quan cho thấy rằng chất lượng nước và đất xung quanh không phải là những thước đo chính cho tốc độ phát triển cây đước ở Xuân Thủy. Những ghi chép cũ đã kết luận rằng việc sử dụng đất để nuôi tôm là tác nhân chính dẫn tới suy giảm loài đước trong quá khứ. Bên cạnh đó, kết quả phân tích tương quan cho thấy sựtrùng hợp về mặt địa lý giữa sự phân mảnh của loài đước và những vùng nước bị ảnh hưởng do việc nuôi trồng thủy sản. Hơn nữa, sự phân bố bất thường của các giá trị đo mức độ tập trung kim loại cũng tương ứng với các hoạt động nuôi trồng thủy sản và khai thác cát của con người. Những phân tích nêu trên và nghiên cứu về hoạt động của con người tại vùng đệm của Xuân Thủy sẽ cung cấp những thông tin cơ bản về những mối đe dọa môi trường hệ sinh thái tại Vườn Quốc Gia Xuân Thủy.
284

Habitat fragmentation, livelihoods and conservation : implications for Tarangire National Park.

Porokwa, Jacob T. January 2003 (has links)
This study set out to investigate habitat fragmentation and its implications for wildlife conservation. It focused on Emboreet Ward in the Arusha region of Tanzania, which is in close proximity to the Tarangire National Park. This area, traditionally occupied by the Maasai pastoralists, has undergone several changes, not least of which are changes in the local livelihoods in response to a need for cash and deterioration of state support for animal health care. Dominating these changes is a shift in livelihood strategies from pastoralism to a mix of pastoralism and cropping. Increasingly, land is being cultivated and agricultural opportunities are changing lifestyles, livelihoods and habitat integrity for wildlife. Fragmentation of habitats outside the national park has serious implications for the future of pastoralism and conservation, especially since some species of wildlife migrate seasonally between this park and the adjoining plains. It also has significance for the Maasai whose approach to domestic livestock management is deeply rooted in a culture that does not comfortably accord with the market economy. The study adopted a case study approach, was mainly qualitative, and relied on both primary and secondary data sources. Interviews played a critical part in sourcing primary data from the respondents. Documentary analysis was critical to gathering secondary data. The study shows the future of Tarangire National Park to be intricately woven into the complex and dynamic interaction between the changing economy, the responses of the Maasai whose culture separates them from the market economy, migrants into the area, and the government agencies whose intentions appear to be neither clearly expressed nor interpreted. The study concludes that empowerment lies at the heart of the envisaged change. This is shown to be a necessity for all stakeholders operating within a proposed integrating structure. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.
285

Mammoth Cave National Park : distribution and classification of woody vegetation

Shell, Melissa K. January 1995 (has links)
Mammoth Cave National Park (MCNP) contains a diversity of forest types due to a complex mosaic of landform, rock types and land-use history. The point-centered quarter method was used to collect data for a forested vegetation classification. Stratified random sampling was done in each of the various site types found within the boundaries of MCNP. A classification based on the information available in the matrix of species importance values from each site type was constructed using two-way indicator species analysis (TWINSPAN). Geographic Information System (GIS) analysis was used to devise an automated vegetation mapping model that can be used to predict vegetation from environmental variables. A tool to assess the accuracy of model predictions was devised. The predicted vegetation map was stored within the GIS, and allows access to a variety of data associated with inventored, classifed, and predicted plant community types. / Department of Biology
286

Pond-Breeding Amphibian Species Distributions in a Beaver-Modified Landscape, Acadia National Park, Mount Desert Island, Maine

Cunningham, Jesse January 2003 (has links) (PDF)
No description available.
287

Tourism policy, biodiversity conservation and management: a case study of the Kruger National Park, South Africa

Zhou, Leocadia January 2009 (has links)
The Kruger National Park (KNP) management has recently made considerable progress in enacting new policies to address biodiversity conservation and management challenges. However, the interlinkages among the new policies to support biodiversity conservation and management have not been evaluated, particularly the principles and approaches, and how these interact in terms of policy decision-making at the economic and political levels. This study seeks to evaluate the interlinkages among the new policies and how they affect one another, as an avenue to promote a more integrated and comprehensive policy implementation. These policies include the tourism policy, the elephant management policy, and the water provision policy. At policy-making level, the integration of these three policies enhances the possibilities for balancing and controlling the pressures exerted on environmental resources. At the implementation level, it offers a framework for the coordination of the interventions of the policies in space so as to recognise and capitalize on their synergies. Given the inevitably multifarious and departmentalized nature of policy formulation in the KNP, there is a need for the analysis of interlinkages amongst policies. The conceptual framework underpinning this study derives much from Briassoulis’ (2004) policy integration. The research utilizes both qualitative and quantitative research methods, and focuses on selected camp sites within the Park. The findings indicate that current procedures for tourism policy-making and implementation are weak, and little is done by way of impact assessment. This has been attributed to the lack of capacity at the KNP. The findings also reconfirm that policy-making is too fragmented. As a result, policy coordination and cooperation among park managers is weak. This study suggests that an environmental policy integration approach can lead to improved policy-making and implementation. Informed by the data collected from interviews, questionnaires and document analyses, a management framework has been developed to demonstrate how an integrated approach to Environmental Policy Integration (EPI) or management can help sustain the practice of wildlife tourism and support biodiversity conservation. It is concluded that greater realisation of integrated policy-making and implementation in the KNP can be achieved by establishing a formal coordinating office. However, a special feature of KNP policy-making is its widespread consultation system that can provide a fertile ground for enhancing EPI.
288

Habitat suitability and behaviour of springbok (Antidorcas marsupialis) at Augrabies Falls National Park, South Africa

Reid, Caroline January 2005 (has links)
Habitat selection may be considered a behavioural consequence of an individual actively selecting where it lives or passively persisting in a certain habitat. There are a variety of approaches to assessing habitat selection, including relating densities to predefined habitats and the characteristics of these habitats, measuring the behaviour of animals within predefined habitats in order to assess the relative benefits to the animal and comparing these between habitats, and using optimality theory to allow the animal to provide measures of its preference for particular habitats or patches. Each approach provides different perspectives on an animal’s choice and use of habitat, with some approaches working more effectively with certain species or habitats than others. There have, however, been no attempts to apply all these approaches to a single species at a single site. The objective of this study was therefore to apply the three above-mentioned approaches to assess habitat use and quality to a single species, the springbok (Antidorcas marsupialis) at the Augrabies Falls National Park (AFNP), on the northern bank of the Orange River, in order to provide the basis for further work on comparing and integrating these approaches. The relative abundance of springbok in Augrabies Falls National park was used to develop a habitat suitability model for the park, and thus determine the habitat variables that influenced habitat suitability. Isodar analysis revealed information on the mechanisms underlying habitat preference. Behavioural models were developed to improve our understanding of how springbok behaviour changes in relation to the habitat, and incorporated the variables identified in the habitat suitability model. The different spatial and temporal scales influencing springbok habitat selection were determined using optimal foraging theory and giving-up densities. Springbok preferred open habitats providing high food quality. Springbok behaviour was related to the foraging and predation risk characteristics of the habitat, and springbok varied their temporal and spatial utilisation so as to minimise their risk of predation and maximise their food intake. The habitat suitability model, behaviour models and giving-up densities were compared for ease of use and applicability. Using giving-up densities to reveal habitat suitability had greater applicability and was both efficient and objective.
289

Body composition estimation and nutritional status of African buffalo (Syncerus caffer) in the Kruger National park

Erasmus, Marius Eugene Anton 13 December 2006 (has links)
Please read the abstract in the 00front part of this document / Dissertation (MSc Agric (Production Physiology))--University of Pretoria, 2006. / Animal and Wildlife Sciences / unrestricted
290

Elephant feeding behaviour and forage offtake implications in the Addo Elephant National Park

Lessing, Joan Susanna January 2007 (has links)
Elephants, as megaherbivores and keystone species have major impacts, both positive and negative, on ecosystems such as the Subtropical Thicket of the Eastern Cape. The feeding behaviour of elephants was quantified so as to firstly determine the preferred feeding heights of elephants, and secondly to determine if feeding behaviour and impact varies with size and sex. The preferred feeding height was determined with experimental feeding trials. Feeding height, pluck size, foraging rate and the proportion of plant material discarded were used to test for differences between elephants of different sizes and sexes in the Addo Elephant National Park. The influence of plant growth form on sex-specific feeding was also considered. Elephants preferred to feed at the lowest heights. The preferred feeding height was not related to body size. A wide range of feeding heights was recorded including and extending beyond, both the preferred and maximum feeding height of co-existing indigenous browsers. There was no difference in feeding height between the sizes and sexes. In free ranging conditions, all elephants fed at levels above the preferred foraging height when browsing. There was no difference in feeding behaviour between the different sized elephants, or between males and females. Adult elephants however exhibited larger ranges of feeding heights, pluck sizes, foraging rates and intake rates, including the maximum and minimum values. Growth form influenced the feeding of male and female elephants differently. Elephant feeding behaviour appears to limit opportunities for resource partitioning by way of feeding height segregation. Elephants are also capable of dominating the browse resources available to co-existing browsers by removing large amounts of forage at lower heights. The extent of elephant impact seems to be comparable between sizes and sexes, although adults and especially larger males are often able to use foraging opportunities that other elephants can not effectively utilize. Findings suggest that the feeding heights of elephants are determined by forage availability and reflect the diet in terms of browse or grass. The findings can be used, together with browse inventory methods, to determine browse resources available to elephants, and can also be used to develop monitoring tools to assess the impacts of elephants on plants.

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