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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.
151

Forest Resource Use, Land-Use, and Ecotourism in the Río Plátano Biosphere Reserve, Honduras

Friedle, Christina Marie 01 May 2005 (has links)
The Río Pláttano Biosphere Reserve, a tropical rainforest reserve in the northeastern corner of Honduras, is home to several subsistence-based indigenous groups, including the Miskito, Pech and Garifuna, as well as the non-indigenous Ladinos. Communities within the reserve depend on forest resources, swidden agriculture, marine resources and/or small-scale ranching as the foundations for local economies. Regulations placed on these subsistence practices, after establishment of the biosphere reserve in 1980, have created unique and new pressures and resulted in a blend of traditional and innovative resource use. A notable result is the promotion of ecotourism as a solution for meeting the economic needs of local populations while conserving local resources. This thesis documents current resource use in the Miskito and Ladino communities of Banaka, Brans, and Fuente de Jacob, in the Río Pláttano Biosphere Reserve and the potential of ecotourism to maintain both local economies and consumption of tropical rainforest resources in these communities. Analysis suggests that a community-based approach to ecotourism can result in economic benefits and maintain local culture. This thesis documents current resource use (agricultural crops and trees, gathered and cultivated plants, tree-use, and hunting), resident perspectives on ecotourism development and industry, and provides the foundation for long-term monitoring and analysis on the effects of ecotomism on forest resource and land-use in the greater Banaka region.
152

The parcelization of the open range, a conflict in land use : grazing rights versus residential and recreation land sales in Klickitat County, Washington

Olson, Dennis A. 01 January 1980 (has links)
The threefold question researched herein is: (1) What are the extent and potential economic consequences of land parcelization in Klickitat County?, (2)What are the political and social costs of parcelization?, and (3) What measures today are, or could be, used to ameliorate the land use conflict? These are answered by studying the various aspects of the problem, including the historic land use change, legal mechanisms which regulate livestock grazing and land parcelization; taxation; the economic-effect upon livestock production; crime and social conflict; costs to county services; and environmental impacts. The geography of the change itself is depicted on several maps.
153

Examining the Effects of Climate Change and Urban Development on Water Demand: A Multi-Scale Analysis of Future Water Demand in Hillsboro, Oregon

House-Peters, Lily 01 January 2010 (has links)
In the Portland, Oregon, metropolitan area, suburban cities such as Hillsboro are projected to grow as people seek affordable housing near a rapidly growing metropolis. This thesis examines the combined impact of'c1imate change and urban development on both neighborhood and municipal scale residential water demand in Hillsboro, Oregon. I use two models, a surface energy balance model, Local-scale Urban Meteorological Parameterization Scheme (LUMPS), and a system dynamics model, CCDomestic, to investigate changes in residential water demand in the 2040s at two distinct spatial scales, the neighborhood and the municipality. I calibrate and validate each model to the reference period and then simulate the future (2030-2059) under three statistically downscaled global climate models and two urban development scenarios. The findings of this study indicate that climate change and urban development will not evenly affect water consumption in neighborhoods across a city. Instead, the current land cover and residential density of a neighborhood exert an important influence on the response. Heavily vegetated neighborhoods exhibit large increases in water demand under urban sprawl and warming scenarios, while neighborhoods dominated by impervious surfaces decrease water consumption under sprawl scenarios and show little change in water consumption under combined sprawl and warming scenarios. At the municipal scale findings suggest that water demand is highly sensitive to urban design and management and that the combination of urban densification and water conservation regulations could mitigate increases in water consumption from population growth and climate change.
154

Lives, Livelihoods, and Landscapes: A Study of Land Use and Social Change in Northeastern Nepal

Anderson, Jennifer Leigh 01 January 2006 (has links)
This thesis explores the forces of change in lives and landscapes that have altered the Lamosangu-to-Everest route in northeastern Nepal and shows how a transect in photographs and conversations across the east-central Himalaya allows us insight and a greater understanding into the processes and consequences of this change. Three forces of change over the last twenty-five years dominated discussions with local informants: the rise of the "People's War"-Nepal's Maoist Insurgency beginning in 1996; the Democratic Revolution of 1990; and dependence on tourism for livelihood after the establishment of Sagarmatha National Park in 1976. Understanding the cultural-historical context for these forces is necessary to understand the concerns of today's residents living along the Lamosangu-to-Mount Everest Base Camp transect. The visual and ethnographic evidence discussed in this thesis takes a larger role than strict analysis of conspicuous large-scale land use change and I hope the comparative 200 I images will be used as benchmarks for future research as well as for further exploration into the ways people and place have been represented.
155

An Examination of Commercial Medicinal Plant Harvests, Mount Hood National Forest, Oregon

Campbell, Shannon Michelle 01 January 2000 (has links)
During the past fifteen years, non-timber or special forest products have become an important economic resource in the Pacific Northwest. These products are primarily derived from understory species and contribute approximately $200 million to the regional economy. Medicinal plants are a little researched component of the non-timber forest product industry that relies on cultivated and wildcrafted (or wild-collected) medicinal plant species. This study examines the commercial extraction of wildcrafted medicinal plants from Mount Hood National Forest. Specifically, this study documents the medicinal plant species extracted from Mount Hood National Forest, their annual yield amounts, harvesting methods, and the changes in cover of target species after harvest. This research uses survey data obtained from employees of two herbal companies and representatives of the U.S. Forest Service to describe medicinal plant extraction and administration as it pertains to the commercial extraction of plant species from Mount Hood National Forest. Field data were also used to examine changes in plant cover for four medicinal plant species (kinnikinnick, yarrow, Oregon grape and valerian) following harvest. Field results indicate that medicinal plant cover decreased significantly in all but one harvested sampling unit. Permanent unit markers were established at all the study sites to provide opportunities for long-term monitoring of target species responses to harvest. Eleven medicinal plant species are commonly collected for commercial purposes from Mount Hood National Forest. The general lack of regulation and enforcement of commercial medicinal plant extraction coupled with an increasing demand for wildcrafted medicinal plants warrant a need for increased collaboration between regulatory agencies, herbal companies, and the general public. Additional management and research recommendations regarding the ecological impacts of medicinal plant removal are also presented.
156

Oxygen Demand Trends, Land Cover Change, and Water Quality Management for an Urbanizing Oregon Watershed

Boeder, Michael Karl 01 January 2006 (has links)
In-stream aquatic habitat depends on adequate levels of dissolved oxygen. Human alteration of the landscape has an extensive influence on the biogeochemical processes that drive oxygen cycling in streams. Historic datasets allow researchers to track trends in chemical parameters concomitant with urbanization, while land cover change analysis allows researchers to identify linkages between water quality trends and landscape change. Using the Seasonal Kendall's test, I examined water quality trends in oxygen demand variables during the mid-1990s to 2003, for twelve sites in the Rock Creek sub-watershed of the Tualatin River, northwest Oregon. Significant trends occurred in each parameter. Dissolved oxygen (DO (%sat)) increased at five sites. Chemical oxygen demand (COD) decreased at seven sites. Total Kjeldahl nitrogen (TKN) decreased at five sites and increased at one site. Ammonium (NH3-N) decreased at one site and increased at one site. Multiple linear regression indicates that nitrogenous oxygen demand accounts for a significant amount of variance in COD at ten of the twelve sites (adjusted R2values from 0.14 to 0.73). Aerial photo interpretation revealed significant land cover change in agricultural land cover (-8% for the entire basin area) and residential land cover (+10% for the entire basin area). Correlation results between seasonal oxygen demand data and land cover values at multiple scales indicated that: (I) forest cover negatively influences COD at the full sub-basin scale and positively influences NH3-N at local scales, (2) residential land cover positively influences DO (%sat) values at local scales, (3) agricultural land cover does not influence oxygen demand at any land cover assessment scale, ( 4) local topography negatively influences TKN and NH3-N, and (5) urban runoff management infrastructure correlates positively with COD. Study results indicate that, with the exception of forested land, local scale land cover and landscape variables dominate influence on oxygen demand in the Rock Creek basin. Since DO conditions have improved in these streams, watershed management efforts should emphasize local influences in order to continue to maintain stream health.
157

Quantifying Twentieth Century Glacier Change in the Sierra Nevada, California

Basagic, Hassan J. 01 January 2008 (has links)
Numerous small alpine glaciers occupy the high elevation regions of the central and southern Siena Nevada, California. These glaciers change size in response to variations in climate and are therefore important indicators of climate change. An inventory based on USGS topographic maps (l :24,000) revealed 1719 glaciers and perennial snow and ice features for a total area of 39.l5 ±7.52 km2. The number of 'true' glaciers, versus non-moving ice, is estimated to be 118, covering 15.87 ± 1.69 Km2. All glaciers were located on north to northeast aspects, at elevations >3000 m. Historical photographs, geologic evidence, and field mapping were used to determine the magnitude of area loss over the past century at 14 glaciers. These glaciers decreased in area by 31% to 78%, averaging 55%. The rate of area change was determined for multiple time periods for a subset of seven glaciers. Rapid retreat occurred over the first half of the twentieth century beginning in the 1920s in response to warm/dry conditions and continued through the mid-1970s. Recession ceased during the early 1980s, when some glaciers advanced. Since the 1980s each of the seven study glaciers resumed retreat. The uniform timing of changes in area amongst study glaciers suggests a response to regional climate, while the magnitude of change is influenced by local topographic effects. Glacier area changes correlate with changes in spring and summer air temperatures. Winter precipitation is statistically unrelated to changes in glacier area. Headwall cliffs above the glaciers alter the glacier responses by reducing incoming shortwave radiation and enhancing snow accumulation via avalanching.
158

Navigation on the San Joaquin River, 1848-1925

Birtwhistle, John Wynn 01 January 1962 (has links)
This thesis is a history of the navigation on the San Joaquin River from 1848 until 1925. The main purpose of the thesis will be to examine chronologically any and all events and factors concerned with the navigation of the river during that period of time. The first chapter will survey the geographical and historical background of the San Joaquin River. The emphasis will be placed on the river's use for navigation. Since the upper, southern third of the San Joaquin Valley does not drain into the San Joaquin River, only those areas between the Kings River on the south and the Cosumnes River on the north will be included in this study.
159

Environmental Perceptions of Canyonlands National Park, Utah, 1961-1971

Pashibin, Tate 12 June 2019 (has links)
No description available.
160

Geologic mapping of the Sparta 7.5-minute quadrangle in northern Mississippi via remote sensing, traditional geologic survey, and applied geospatial information systems methods

Parnell, Rayford Dean 09 December 2022 (has links) (PDF)
Traditional geologic mapping involves substantial time and labor in the field as geologic contacts are manually examined and interpreted. The processes of mapping geologic contacts can be condensed into a quicker and less laborious process using advances in remote sensing and GIS (geospatial information systems), including increased resolution and computerized data management and interpretation. Application of these advances reduces the costs and time of geologic mapping. The Sparta 7.5-minute quadrangle provides a mostly unaltered view of regional Paleocene and Upper Cretaceous geology due to its rural locale, lack of development, and stream topography. Recently LiDAR (Light Detection And Ranging) survey data covering the Sparta quadrangle were collected. These data were not available during previous attempts to map the area using computer modeling. With these new data, high-resolution topographic maps have been produced based on modern satellite imagery together with pre-existing maps of the Sparta quadrangle, which support improved geologic mapping.

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