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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.
81

Negotiated Living: An Ethno-Historical Perspective of Punta Allen

McRae, David Thomas 12 1900 (has links)
Situated within the jurisdiction of the Municipality of Tulum and within the Sian Ka'an Biosphere gives the village of Punta Allen a distinctive agency in determining their role in the on-going development of tourism in the region that is not given to other communities in the state. This unique circumstance facilitates a dialogue between the reserve, the municipality, and the business cooperatives of Punta Allen that produce a negotiated living. Through the negotiations with the reserve and Tulum, the lobster fishing and tourism cooperatives are given the opportunity to have a relatively significant role in determining the future of Punta Allen in regards to tourism.
82

Marginal protection : sustainable development, social resilience and migration within natural protected areas of the Trans-Mexican Volcanic Belt, central Mexico

Strauss, Simon Yale. January 2006 (has links)
No description available.
83

Social Relationships within Ecotourism Cooperation : Case of the ARK56 Network

Hammerfeldt, Caroline January 2023 (has links)
The inclusion of ecotourism into biosphere reserves to enhance sustainable development has increased the importance of tourism stakeholders’ relationships. Therefore, this research aims to explore how the quality of social relationships among tourism stakeholders affects ecotourism cooperation in the Blekinge Archipelago biosphere reserve. This is accomplished by using social capital as a theoretical lens for conceptualizing relationships between ecotourism stakeholders. A qualitative case study of the ARK56 network has been conducted, incorporating 8 in-depth interviews with ecotourism operators in the Blekinge Archipelago biosphere reserve. The results indicated that the regional network ARK56 is essential for tourism operators since it provides a broad network of contacts and encourages cooperation among the members. It is argued that a good working relationship based on trust and reciprocity facilitates efficient cooperation within the ARK56 network and that a balance between bridging and bonding social capital was identified which contributes to successful cooperation.
84

From enemies to allies : transforming the relationship with local communities in the management of protected areas : the uncertain case of the Monarch Butterfly Biosphere Reserve

Joli-Coeur, Félix-Antoine January 2004 (has links)
No description available.
85

Assessment of sustainable leaf harvest from the understory palm, Chamaedorea radicalis

Ash, Jeremy D. 01 August 2007 (has links)
No description available.
86

Enrichment planting of an understory palm: Effect of microenvironmental variables on seedling establishment, growth, and survival

Kilroy, Hayley A. 05 May 2008 (has links)
No description available.
87

Assessing Factors that Contribute to Reduced Deforestation and Successful Community Forest Management in Guatemala’s Maya Biosphere Reserve

Fortmann, Lea 29 October 2014 (has links)
No description available.
88

Terrestrial ecosystem impacts on air quality

Wong, Yik Hong 16 July 2024 (has links)
The terrestrial ecosystem is an integral component of the Earth System. Constant atmosphere-biosphere exchanges of energy and material affect both the physics and chemistry of the atmosphere. While the general roles of terrestrial ecosystems in regulating ozone and particulate matter air pollution have long been acknowledged, our understanding at both individual process and system level are far from perfect. Also, new process-level discoveries about terrestrial atmosphere-biosphere exchanges are not timely incorporated in numerical models routinely used to study and forecast air quality. These hinder our ability to understand how air quality respond to environmental changes and variabilities. Chapter 1 of this dissertation provides a brief overview on these topics. In Chapter 2 of this dissertation (Wong et al., 2019), we conduct global long-term simulations of ozone dry deposition velocity with four different types of dry deposition parameterizations. We find that none of the tested parameterizations universally stands out in terms of matching observed ozone deposition velocity over different land cover types. Combining this with sensitivity simulations from a global 3-D atmospheric chemistry model (GEOS-Chem), we find that the choice of dry deposition parameterizations can affect the mean, trend and variability of simulated surface O3 level. In Chapter 3 of this dissertation (Wong et al., 2022), we analyze long-term ozone flux observation from three field sites to examine the effects of extreme heat and dryness on ozone deposition. We find that non-stomatal ozone uptake tends to increase during hot days, which either partially offsets or dominates over the reduction in stomatal ozone uptake anticipated by ecophysiological theory. While the response of ozone deposition to dryness is more varied, changes in non-stomatal deposition are usually important. Current dry deposition parameterizations often fail to capture such changes in non-stomatal ozone uptake, resulting in considerable potential error in simulated surface ozone level during hot and dry days. In Chapter 4 of this dissertation (Wong and Geddes, 2021), we conduct global GEOS-Chem numerical experiments with anthropogenic emission inventories and land surface remote sensing products to compare the effects land cover versus land management changes on O3 and fine particulate matter air quality over 1992 – 2014. We find that land cover has stronger effects on O3, while land management has stronger effects on fine particulate matter pollution. We also find that land management has significantly altered regional and global nitrogen deposition, and therefore the risk of critical load exceedance. Chapter 5 of this dissertation includes the concluding remarks and suggestions for future work. In addition, I outline and present the preliminary result from a project examining the future of soil reactive nitrogen emissions and their impacts on air quality.
89

Participatory mapping of ecosystem service values in the Kristianstads Vattenrike Biosphere Reserve

Schwarze, Marleen January 2024 (has links)
UNESCO Biosphere Reserves are examples of multifunctional landscapes recognized as sources of ecosystem services and laboratories for sustainable development. Participatory mapping of ecosystem services reveals where residents value ecosystem services in a landscape. This approach is expected to provide useful knowledge to inform land use decision-making. However, the knowledge about the spatial distribution of ecosystem service values in Biosphere Reserves and the usefulness of this knowledge for practitioners remains scarce. Through the application of Public Participation Geographic Information Systems (PPGIS) in the Kristianstads Vattenrike Biosphere Reserve located in Southern Sweden, this study identifies i) hotspots and ii) bundles of ecosystem service values, as well as iii) spatial patterns of ecosystem service values regarding the three Biosphere Reserve management zones. Complementary, this study assesses the potential usefulness of the PPGIS-derived knowledge by analyzing qualitative data from a workshop with practitioners of the Kristianstads Vattenrike Biosphere Reserve. My findings reveal distinct patterns of ecosystem service values across Kristianstads Vattenrike Biosphere Reserve that reflect the Biosphere Reserve zones’ management goals. The ecosystem service values were clustered around wetlands and the densest populated areas. Respondents mapped predominantly places for outdoor recreation, biodiversity, and places with existential value. The results highlight the importance of cultural and regulating ecosystem services to people in the Biosphere Reserve. Additionally, practitioners involved in Biosphere Reserve management emphasized the potential strategic usefulness of the PPGIS knowledge for their nature restoration work.
90

Evolution of the Geohydrologic Cycle During the Past 700 Million Years

Angel, Adam M. 20 April 2018 (has links)
Water is a primary driver of the physical, geochemical and biological evolution of the Earth. The near-surface hydrosphere (exosphere) includes the atmosphere, cryosphere (glacial and polar ice), the biosphere, surface water, groundwater, and the oceans. The amounts of water in these various reservoirs of the hydrologic cycle have likely varied significantly over the past 700 Ma, with the cryosphere and continental biosphere reservoirs likely showing the most dramatic variations relative to the modern. For example, 700 Ma, during snowball-Earth conditions, the planet may have been almost entirely enveloped in ice, whereas throughout much of the Phanerozoic, greenhouse conditions predominately prevailed and the Earth had a much smaller cryosphere. Similarly, before about 444 Ma and the proliferation of land plants, the continental biosphere reservoir would have effectively non-existent. However, today, plants play a critical role in storage and transfer of water within the hydrologic cycle. Because the amount of water in the exosphere is thought to have remained relatively constant during the past 700 Ma, variations in the amounts of water held by the in the various exogenic reservoirs exert concomitant effects on other reservoirs in the exosphere. We present a conceptual and numerical model that examines variations in the amount of water in the various reservoirs of the near-surface hydrologic cycle (exosphere) during the past 700 Ma and quantify variations in the rates of exchange of water between these reservoirs in deep time. Variations in the sizes of major reservoirs are primarily controlled by changes in global average temperature, and the movement of water between the atmosphere, surface water, and ocean reservoirs varies in concert with the waxing and waning of the cryosphere. We find that variations in the sizes of major reservoirs are primarily controlled by changes in global average temperature, and the flux of water between the atmosphere, surface water, and ocean reservoirs varies in concert with the waxing and waning of the cryosphere, with some fluxes decreasing to 0.0 kg/yr during snowball-Earth conditions. We find that the amount of water precipitated from the atmosphere to the cryosphere increases from greenhouse conditions to -10.5°C and decreases from -10.5°C to snowball-earth conditions, highlighting "tipping-point" behavior due to changes in temperature and cryosphere surface area. The amount of surface runoff to the oceans varies in proportion to the amount of water removed from the surface water reservoir and transferred into the continental biosphere. Variations in the movement of water between near-surface reservoirs that are driven by the waxing and waning of the cryosphere and emergence and growth of plant life thus have significant implications for the transfer of weathering products to the oceans and could contribute to short-term (<1 Ma) variations in seawater composition and isotopic signatures. / Ph. D. / Water drives the evolution of the planet, and the distribution of water throughout Earth’s atmosphere and surface has varied during the geologic past. The amounts of water in the atmosphere, polar ice, the biosphere, surface water, groundwater, and the oceans have changed during the past 700 million years, and the polar ice and biosphere reservoirs have undergone the most significant changes during that time. For example, at extremely cold conditions the planet may have been covered in ice, and during warmer conditions the planet may have been covered in little to no ice. Similarly, before 444 million years ago, the biosphere on Earth’s continental surface was almost non-existent. The evolution of land plants after 444 Ma resulted in an increase in the amount of water in the biosphere. Changes in the amounts of water in one reservoir of water over time will have effects on the other reservoirs of water in the water cycle. We produce a numerical model that examines changes in the sizes of water cycle reservoirs and the movement of water between those reservoirs during the past 700 million years. Variations in reservoir sizes are primarily controlled by changes in global average temperature, and the movement of water between the atmosphere, surface water, and ocean reservoirs varies with changes in the amount of polar ice on Earth. We find that total annual precipitation to polar ice increases from greenhouse temperatures to - 10.5°C and decreases from -10.5°C to cold snowball-earth temperatures due to changes in both temperature and the surface area of polar ice. The amount of surface runoff to the oceans varies in proportion to the amount of water removed from the surface water reservoir and transferred into the continental biosphere. Variations in the movement of water between reservoirs that are driven by the waxing and waning of polar ice and the growth of plant life have significant implications for the movement of dissolved material to the oceans and could contribute to short-term (<1 Ma) variations in seawater chemistry.

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