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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.
91

Acid deposition effects on soil chemistry and forest growth on the Monongahela National Forest

Elias, Patricia Elena 29 August 2008 (has links)
Acid deposition (AD) results largely from the combustion of fossil fuels, and has been found to negatively impact forest ecosystems. AD may acidify soils through base cation leaching or Al mobilization, may cause accumulation of nitrates and sulfates in soils, and in some cases has been related to forest decline. The Monongahela National Forest (MNF) lies downwind from many sources of AD pollution, and average deposition pH is around 4.4. Therefore, managers are concerned about the possible deleterious effects of AD on the forest ecosystem. During the 2006 Forest Plan revision, evaluation of site sensitivity to acidification was specifically stated as a step in the Forest's adaptive management process. To meet this management objective, forest practitioners must understand the effects AD has on the forest, prescribe appropriate practices, and be able to monitor for future changes. To address the needs of MNF managers we used Forest Inventory and Analysis (FIA) sites to evaluate forest growth patterns on the Forest and determined the relationship between growth and key indicators of soil acidity. Furthermore, we used those relationships to create a map of site resistance to acidification across the MNF. To further develop a monitoring scheme we assessed two soil sampling protocols and two soil analysis methods for their suitability for monitoring AD-related changes in soil chemistry. Additionally, we evaluated the utility of dendrochronological and foliar sampling as AD-specific monitoring methods. Across all FIA sites on the MNF periodic mean annual volume increment (PMAVI) ranged from -9.5 m³ha⁻¹yr¹ to 11.8 m³ha⁻¹yr¹, suggesting lower-than-expected growth on two-thirds of the sites. Growth was compared to soil indicators of acidity on 30 FIA sites. In the surface horizon, effective base saturation (+), Ca concentration (+), base saturation (+), K concentration (+), Fe concentration (-), Ca/Al molar ratio (+), and Mg/Al molar ratio (+), were correlated with PMAVI (p ≤ 0.1). In the subsurface horizon pH<sub>(w)</sub> (+), effective base saturation (+), Al concentration (-), and K concentration (-) were correlated with PMAVI. Site resistance to acidification was mapped based on site parent material, aspect, elevation, soil depth, and soil texture. There was a significant (p ≤ 0.1) positive correlation between PMAVI and a resistance index developed using five soil and site factors. Resistance was also compared with key soil indicators of AD-induced decline on 28 sites across the forest, and pH, effective base saturation, and Al content were found to be the best indicators related to resistance index. Resistance index was used to create a map of the MNF, of which 14% was highly resistant (RI ≥ 0.7), 57% was moderately resistant (0.7 > RI > 0.45) and 29% was slightly resistant (RI ≤ 0.45). The first of our monitoring program evaluations compared soil sampling and analysis methods on 30 FIA plots. Analyses of variance showed that soil pH, effective base saturation, Ca/Al molar ratio, and sum of bases varied significantly with sampling protocol. We also compared lab analyses methods and found that if sampling by horizon, a linear relationship can be used to estimate Ca/Al<sub>SrCl₂</sub> ratio using NH₄Cl extractions. The second monitoring approach evaluated the utility of a northern red oak (Quercus rubra L.) dendrochronology on two FIA plots. This analysis suggests that pollution on the MNF caused a decrease in growth rate during the 50-year period from 1940 to 1990. There were no differences among ring width increment and basal area increment between the two sites. From 1900 to 2007 the two sites showed 58.5% similarity in growth trends, but these could not be attributed to a dissimilar influence of AD. The third monitoring approach evaluated the relationship between foliar and soil chemical indicators. Across FIA plots, nutrient concentrations varied by tree species. The first year results from a potted-seedling study suggest that soil acidity influences growth, and foliar concentrations are related to growth rates. This evaluation of the effects of AD on the MNF can be used to develop adaptive management plans and a monitoring program that will meet the AD-related objectives of the 2006 Forest Management plan. / Master of Science
92

Wild turkey-road interactions on a Virginia national forest

McDougal, Leigh Ann 14 April 2009 (has links)
I studied wild turkey (Meleagris gallopavo) movements and range use in response to roads and vehicular road use on the George Washington National Forest, Virginia. Radio-equipped wild turkeys used areas within 150 m of state roads less than expected and areas > 450m from ail roads greater than expected. Turkeys were observed to cross state roads only in locations where the roads were bordered by woods or fields less than 80 m wide. Seasonal habitat preferences, rather than vehicular road use levels, seemed to dictate turkey use of the area surrounding Forest Service roads. Revegetated Forest Service roads were preferred habitat in the spring and summer. Turkey mortality was not closely related to road type or road use levels. / Master of Science
93

Using linear programming to improve unit planning on the Appalachian National Forests

Porter, John R. January 1974 (has links)
A linear programming model for multiple use was developed for the High Knob Unit of the Jefferson National Forest. The model was intended to be a pilot study for the development of similar models for other units in the Appalachians. The model was developed to provide information about trade-offs between timber, recreational activities, and budgets during the 10 year planning period. Currently used estimates and "rules of thumb" were used as the means for relating the activities considered in the model. The objective function used was timber maximization and it was constrained by the activity and budget constraints. The maximum possible timber volume that could be cut was found for the High Knob Unit by using only acreage constraints on the objective function. Then the constraints for the other activities were added, each of which being tied to the timber variables. An initial optimal solution was found which not only gave values for the amounts of the activities that would be best to produce but also where they were to occur on the ground. To provide information about trade-offs, a sensitivity analysis was done to provide a series of solutions for the High Knob Unit. These solutions were evaluated and recommendations were made for the High Knob Unit. Benefits and limitations of the model were discussed as were the problems encountered in developing the High Knob LP. Suggestions for future study were also made. / Master of Science
94

Spatial Distribution of Four Exotic Plants in Relation to Physical Environmental Factors with Analysis using GIS

Murray, David Patrick 05 March 2009 (has links)
The spatial distributions of four plant species native to Asia, yet considered invasive in southwestern Virginia, were studied in order to produce predictive habitat maps. The study took place in the mountains to the north of Blacksburg, VA, on National Forest lands. A random GPS survey of each of the four species, Microstegium vimineum, Lonicera japonica, Rosa multiflora and Elaeagnus umbellate, was used in combination with a series of Geographic Information System (GIS) layers representing environmental variables (Elevation, Aspect, Roads, Trails, Streams, & Normalized Difference Moisture Index) to produce logistic regression models. After field- validating the models, the models were ranked according to usefulness, with the E. umbellate model proving most accurate. It is hoped that such GIS models will allow forest managers to more productively search for invasive species within their jurisdiction, by indicating sites more likely to provide habitat suitable to the invasive species described by the model. A non-GIS search for correlations between the study species' presence and field-collected discrete environmental variables was also included. Both Disturbance and Canopy Cover were considered for their effect upon Microstegium vimineum, Lonicera japonica, Rosa multiflora and Elaeagnus umbellate presence. Using Pearson's Correlation with the Canopy Cover data, and Chi-squared Correlation with the Disturbance data, only R. multiflora and E. umbellate showed significant correlation to decreasing canopy cover. / Master of Science
95

An Axis Through Nature: Ranger Station at Pandapas Pond

Todd, Alan Curry 08 May 2007 (has links)
My thesis is a human intervention into the tranquil and natural environment of Pandapas Pond and the Jefferson National Forest. Although the form of the intervention embraces the landscape and natural land formations, its purpose is to take the visitor along a path that translates the experience from one of participation to that of observation of the parkâ s surroundings. This is both an investigation of an architectural integration with the site and a partial separation of the inhabiter from his/her natural surroundings. / Master of Architecture
96

Wind-Abilities: A Mixed-Use Model for Thoughtful Wind Farm Design

Arledge, Lauren Habenicht 22 June 2017 (has links)
Globally, wind power is leading the renewable energy revolution. While carbon neutral and cost-effective, wind energy infrastructure is immobile and has the potential to profoundly change land use and the visible landscape. As wind technology takes its place as a key contributor to the US energy grid, it becomes clear that these types of projects will come into greater contact with areas occupied by humans, and eventually with wilderness and other more natural areas. This increased visibility and close proximity necessitates the development of future wind farm sites that afford opportunities for auxiliary uses while maintaining their intrinsic value as energy producers. In short, it is important for wind farms to be versatile because land is a finite resource and because over time, increasing numbers of these sites will occupy our landscapes. In the Eastern US, the majority of onshore wind resources suitable for energy development are found along ridge lines in the Appalachian mountains. These mountains are ancient focal points in the landscape, and subsequently host myriad sites of historic, recreational, and scenic significance. In the future, these windswept ridges will likely become targets for wind energy development. This thesis demonstrates a methodology for the thoughtful siting and design of future wind projects in the Appalachian mountains. Opportunities for offsite views, diversified trail experiences, and planned timber harvests are realized by locating a seven-turbine wind park adjacent to the Appalachian Trail in Cherokee National Forest in Carter county, Tennessee. The proposed wind park demonstrates the sound possibility of thoughtfully integrating wind infrastructure along Appalachian ridges in conjunction with forestry and recreation opportunities, such as hiking and camping. The design is a wind park rather than a wind farm because in addition to its inherent function as a production landscape, it is also a place that is open to the general public for recreational use. / Master of Landscape Architecture / Wind power is among the fastest-growing renewable energy resources on the planet. While clean and cost-effective, wind turbines are immobile in the landscape and require large areas of land in order to function properly. Due to the vertical nature of wind turbines, much of the land within wind project boundaries is left unused. As more wind farms are built, they will begin to come into greater contact with areas where humans live and also with more natural areas. In order for this growth to occur responsibly, future wind farm sites should be planned to take advantage of the leftover ground within their boundaries. Incorporating other types of use into wind projects is important because unlike the wind, land is not an unlimited resource. On-shore in the Eastern U.S., the windiest places are the ridge lines in the Appalachian Mountains. In the future these mountains could become targets for wind energy development, which is problematic because they are significant for their environmental, cultural, and recreational values. This thesis provides a method for the thoughtful siting and design of future wind farms in the Appalachian mountains by locating a seven-turbine wind park next to the Appalachian Trail in Carter County, Tennessee. The design shows that it is possible to thoughtfully combine wind energy with other uses like forestry, natural resource conservation, and various types of recreation along Appalachian ridges. The design is a wind park rather than a wind farm because in addition to its basic function as a production facility, it is also a place that is open to the general public for recreational use.
97

Den Tree Avaliability and Denning Success of Black Bears on Industrial Forest Lands and National Forest Lands in Virginia and West Virginia

Quince, Gyasi Adrian 09 July 2002 (has links)
During 1999-2001, potential den trees and denning success of black bears was investigated on industrial forest lands and national forest lands in Virginia and West Virginia. One hundred and fifty seven potential den trees were found on five study areas, 135 on national forest lands and 22 on the industrial forest lands. Twenty-seven hollow potential den trees were found, 22 on national forest lands and 5 on industrial forest lands. Densities of potential den trees ranged from 12.5/km2 to 437.5/km2 on the national forest lands and on the industrial forest lands the densities ranged from 0-187.5/km2. There were significantly higher densities (F1, 69=5.86, P=0.0181) of potential den trees on the national forest land than on the industrial forest land. There were also significantly (F=2, 68=7.86 P=0.0008) higher densities of hollow potential den trees based on the stand age class. Denning success for females expected to have cubs was 98% (n=46) in tree dens on national forest lands and 100% (n=8) on industrial forest lands. Denning success for females expected to have cubs was 76% (n=55) in ground dens on national forest lands and 80% (n=5) in ground dens on industrial forest lands. Females expected to have cubs on the national forest lands had an overall denning success of 89% (n=80) and on industrial forest lands there was overall, 92% (n=13) denning success. Chi-square tests showed that abandonment of dens by bears was significantly higher (x2=19.02, 1df) in ground dens than in tree dens. Litter sizes were not different from national forest lands and industrial forest lands (t=-0.36, 44df, P=0.84). The mean litter sizes on the national forest lands was 2.55 (SE=0.16) cubs per litter and on the industrial forest land 2.4 (SE=0.22) cubs per litter. / Master of Science
98

Ambivalent Landscapes: An Historical Geography of Recreation and Tourism on Mount Hood, Oregon

Mitchell, Ryan Franklin 01 June 2005 (has links)
Mount Hood is an Oregon icon. The mountain has as long and rich a history of recreation and tourism as almost any other place in the American West. But contemporary landscapes on Mount Hood reveal a recreation and tourism industry that has struggled to assert itself, and a distinct geographic divide is evident in the manner in which tourism has been developed. Why? In this study I chronicle the historical geography of recreation and tourism on Mount Hood. I examine the evolution of its character and pattern, and the ways in which various communities have used it to invest meaning in the places they call home. Despite the efforts of early boosters, Mount Hood has never been home to an elite destination resort like Aspen, Sun Valley, or Vail. Instead, modest recreation developed alongside timber and agriculture, and today the area is primarily a regional attraction. Unlike destinations with national and international clienteles that play a significant role in shaping lives and landscapes, local and regional interests are the primary drivers of recreation and tourism on Mount Hood. Communities on the mountain have incorporated the industry into their lives and landscapes to varying degrees. Mount Hood is also inextricably tied to Portland, and as an integral part of the city's history and identity, reflects its residents' tastes, values, and priorities. This combination of local and metropolitan interests has left an imprint on Mount Hood that reflects tensions and contradictions that define Oregon in the early twenty-first century: past vs. future, old vs. new economies, urban vs. rural inclinations, progress vs. status quo, and upscale vs. modest tastes. Spatially, temporally, and psychologically, Mount Hood straddles the divide between two visions: a service-based economy in the Willamette Valley, heavily dependent on technology, and a traditional, resource-based economy in much of the rest of the state.
99

Contested Visions of Place: People, Power, and Perception on the Columbia's North Shore, 1805-1913

Sinclair, Donna Lynn 11 February 2004 (has links)
This is a narrative of place, of intersections between people, power, and perception of landscape. The environs of the Columbia River Gorge create a very distinct sense of place. Where once a series of three rapids - the Cascades of the Columbia - blocked industrial upriver transport, now Bonneville Dam and Locks allows smooth passage. To the north the vast 1.3 million acre Gifford Pinchot National Forest dominates the landscape. On the Columbia's banks lies the town of Stevenson, Washington, with Carson a few miles away, in a transitory ecological zone between east and west, at the forest's edge. There, community development has been manifestly influenced by human relationships to the landscape. Contested visions of place during the nineteenth century resulted in violent conflict and framed debates over place.Examining struggles over who would control access, first to the Cascades of the Columbia, and then to the timber of the Wind River Valley, provides a venue for examining power - of nature, ideas, and changing human cultures as overlapping groups imposed their views of the good life onto the landscape. As each successive group gained power, the relationships of humans to the land, and to one another, changed. By examining historic connections between river and forest, and between human communities to each, this study identifies multiple meanings of the same environment for different groups. I use a bioregional approach, exploring relationships between land, people and resources on the Columbia's north bank between 1805 and 1913. Power relations at the Cascades and in the forest were determined through conflict, negotiation, and the federal government, with the human relationship to nature influencing outcomes. Conflict often resulted from struggles over access to place, while human groups negotiated their place within the landscape. Nature privileged one group over another through disease, fire, and human perception, while the United States government co-opted place through public land laws, Indian removal, and by measuring and bounding the landscape. Who gained access to the river and forest of the Columbia's north shore, and how they did it, is the focus of this story.
100

Plant community recovery after high severity wildfire and post-fire management in the Klamath Region /

Lopez Ortiz, Maria Jose. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 98-108). Also available on the World Wide Web.

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