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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.
51

Documenting Deforestation at Sidd al-Ahmar, Petra Region, Jordan

Addison, Erin Heather January 2006 (has links)
This study documented the decline of the forests of the Petra Region of Jordan, as represented at Sidd al-Ahmar, within the Petra Archaeological Park. Biogeographical and anthropological methods were employed to explore the history of the forests. Archaeology and historical narratives provided a portrait of the study area from prehistory to the early 20th century. Aerial surveys from 1924 and 2002 were analyzed to quantify changes in forest cover. Mapping and inventory of indicator species measured short-term change between 2003 and 2006. Interviews, field observation and participant observation in the tourist industry provided a socio-cultural context for quantitative analysis and for recommendations for remediation of pressures on the remaining forest. The research documents a 58% decline in tree cover between 1924-2002, and a decline of 4.23% between 2003-2006. The conclusions question concepts such as "landscape integrity" and the usefulness of non-interventionist ideology in an historic and rapidly changing region.
52

Reducing greenhouse gas emissions from deforestation : the United Nations Framework Convention on Climate Change and policy-making in Panama

Guay, Bruno. January 2007 (has links)
The Framework Convention on Climate Change has yet to deal with tropical deforestation although it represents an important source of greenhouse gas emissions. In December 2005 negotiations on a possible regime to reduce emissions from deforestation resume under the impulse of a regime proposal based on the concept of compensated reduction. Over the course of 2006 Panamanian policy-makers working within the National Environmental Authority (ANAM) determine that such a regime is in the interest of Panama given that the integrity of the Kyoto Protocol's existing flexibility mechanisms is protected. However reducing its deforestation rate is not currently possible for Panama due to ANAM's limited institutional capacity to act on the field and limited political capacity to influence the national agenda. Important up-front flows of funds from developed countries combined with the adoption of a progressive project based compensation mechanism could contribute to reverse this trend.
53

Evaluating the Potential Risks and Rewards in the Implementation of a REDD+ Policy in Uganda

Schaftel, Sage 01 January 2014 (has links)
In this thesis, I analyze the potential for a REDD+ program to succeed in Uganda at this time, and I explore why this may or may not be possible. REDD+, which stands for Reducing Deforestation and Forest Degradation, aims to enhance carbon stocks while also conserving and sustainably managing forests. In doing so, REDD+ not only works to offset carbon emission levels and conserve forests and forest biodiversity, but also provides financial benefits to REDD+ participant countries, thus improving the livelihoods of local people living adjacent to forests. This program is widely regarded as the most effective and least risky solution to deforestation and forest degradation in developing countries, however, I argue that this may not be the case. Government documents reveal a rather simplistic and idealistic view of the policy, its implementation process, and desired outcomes, while specific case studies in countries outside of Uganda in which the REDD+ program has been implemented or is in the process of being implemented reveal unaddressed concerns with the mechanism itself and within the surrounding communities. Based on my research, I believe that if the recommendations that I propose are not included in the REDD+ preparation and implementation phases, the REDD+ mechanism is not only predestined to fail, but also to harm the most at-risk stakeholders that it is meant to benefit.
54

The extent of forest fragmentation in New Zealand and its effects on arthropod biodiversity

Ewers, Robert Mark January 2004 (has links)
Historically, New Zealand was almost completely forested below the alpine treeline, but 1000 years of Polynesian and European colonisation has resulted in the destruction of nearly three-quarters of the original forest cover. I assessed historical patterns of deforestation and forest fragmentation in relation to all major topographical, climatic and anthropogenic variables that may drive forest loss. Much of the deforestation occurred in regions with drier climates, reflecting the fact that human population density has always been highest in areas with moderately dry climates and that dry forests burned much more readily and extensively. The large remaining tracts of forest are mainly restricted to high elevations, while the lowland forests have been fragmented into small, isolated remnants. Fragmentation of the surviving forests increases their susceptibility to edge effects and invasion by adventive species, indelibly altering the ecological communities they support. Although a large proportion of the remaining forest is owned or managed by the Department of Conservation, the distribution of that protection is greatly skewed towards areas of low economic value and is not representative of the relative conservation value of landscapes that differ in their environments and degree of forest cover. Forest cover in the majority of New Zealand landscapes has been reduced below the level of an expected extinction threshold of 30 % forest cover in the landscape, and ongoing deforestation threatens to force more landscapes below the critical threshold. Deforestation is still occurring across the country, and it is concerning that current deforestation rates in some areas are far greater than those observed in tropical, developing nations. I showed that the remaining forest fragments in New Zealand have complex, irregular shapes, and find ubiquitous evidence that core habitats within individual fragments are spatially discontinuous, comprising multiple, disjunct cores of small average area. Because population density of forest-interior species typically decreases with decreasing habitat area, multiple, disjunct cores support a lower total population size than a single, discrete core of the same total area. I found in a spatially explicit, landscape-level analysis of habitat fragmentation in New Zealand that simple core-area models consistently overestimate the carrying capacity of habitat fragments. Habitat fragmentation and habitat destruction are widely recognised as two of the leading threats to the continued maintenance of global biodiversity. The effects of habitat fragmentation on biodiversity fall into five categories that describe the spatial and landscape attributes of fragmented ecosystems; (1) fragment area, (2) edge effects, (3) fragment shape, (4) fragment isolation, and (5) matrix structure. Each attribute affects species individually according to their particular biological requirements and life history strategies, leading to complex, and often conflicting, sets of results in the empirical literature. Furthermore, it is now apparent that the effects of fragmentation can take many decades to become apparent and that the spatial arrangement of habitat fragments can interact with other ecological processes to magnify the detrimental impacts of fragmentation on species. I synthesised the published effects of habitat fragmentation on the morphology, distribution and abundance of invertebrate populations, species and communities, and present examples of time lags and synergies from the fragmentation literature. I explicitly considered the underlying mechanisms determining the responses ofindividuals to fragmentation and discussed the role of species traits in determining species vulnerability to changes in the spatial attributes of fragmented landscapes. I sampled 35,461 beetles from a fragmented forest and matrix system in New Zealand over very large gradients of fragment area (10-2 to 106 ha) and edge distances (up to 1,024 m from the forest edge into both the forest and the adjacent matrix interiors). The beetle fauna was very diverse, with 893 species identified in 65 families, representing nearly 20 % of the known species in New Zealand. Beetle communities were strongly structured by forest fragmentation, but in species-specific ways. Distance to edge was consistently shown to have the largest effect on community composition, but, surprisingly, an interaction between area and distance to edge had a stronger impact on community structure than fragment area alone. I developed a new method to partition the variance in community composition that was explained by putative area and edge effects. The method uses backwards stepwise regression to determine significant predictors of gradients in beetle species composition that were identified by canonical ordination. I found that edge effects were driven partially by small-scale alterations to microhabitat and microclimate and partially by changes in landscape composition that varied with distance to edge. In contrast, fragment area effects were driven primarily by edge effects, the strength of which varied significantly with fragment area. I took a novel approach to characterising the responses of 185 common species to habitat edges by modelling species abundances across edges with a general logistic model that described sigmoid trends in abundance for forest specialist and matrix specialist species, as well as unimodal trends in abundance for edge specialist species. I used the second derivatives of the logistic and unimodal models to statistically determine the width of species response zones to edge effects. Beetle species responses to forest edges occurred over far greater scales than previously suspected, with edge response zones for some species extending for more than 1 km. Average edge response zones were 194 m wide and, for many species, began in the forest but extended into the adjacent matrix. Species were categorised according to their responses to fragment area and distance to edge. Closely related species were expected to be placed in similar response categories because they are predicted to share suites of traits that determine their susceptibility or resilience to fragmentation by virtue of common ancestry. Despite many species exhibiting responses that could be grouped into categories, individual species responses to fragmentation were largely idiosyncratic with even closely related species exhibiting strongly contrasting responses to fragmentation.
55

Population pressure, land tenure, deforestation, and farming systems in Haiti : the case of Forét des Pins Reserve

Dolisca, Frito. Teeter, Lawrence Dale. January 2005 (has links) (PDF)
Dissertation (Ph.D.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.
56

Medicine from the forest the impact of deforestation on medicinal plant availability and use in the Bilili Game Management Area, southern Zambia /

Adjemian, Maro, January 1900 (has links)
Written for the Dept. of Geography. Title from title page of PDF (viewed 2009/06/11). Includes bibliographical references.
57

A climatonomic study of the energy and moisture fluxes of the Amazonas Basin with considerations of deforestation effects

Molion, Luiz Carlos Baldicero. January 1975 (has links)
Thesis (Ph. D.)--University of Wisconsin, Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 125-133).
58

Linkages between inequality and environmental degradation an interregional perspective /

Vornovytskyy, Marina S., January 2009 (has links)
Thesis (Ph. D.)--University of Massachusetts Amherst, 2009. / Includes bibliographical references (p. 149-153). Print copy also available.
59

Effects of deforestation and riparian buffers on lotic communities in southeastern Costa Rica : implications for biodiversity conservation in tropical streams /

Lorion, Christopher M. January 1900 (has links)
Thesis (Ph. D., Natural Resources)--University of Idaho and Centro Agronómico Tropical de Investigación y Enseñanza, December 2007. / Major professors: Brian Kennedy and Celia Harvey. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.
60

Type inference based deforestation of functional programs

Chitil, Olaf. Unknown Date (has links) (PDF)
Techn. Hochsch., Diss., 2000--Aachen.

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