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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.
101

Comparative limnology of lakes in the Southern Rocky Mountain Trench, British Columbia

Sparrow, Roger Arthur Hugh January 1963 (has links)
Within a restricted geographical area of British Columbia, a detailed examination was conducted in I960 and 1961 of 9-lakes having similar morphometric and climatic influences, but exhibiting a wide dissolved nutrient range (50 to 1460 ppm). Attempts were made to relate total dissolved solids as well as other chemical and physical indices, to biological factors indicating or influencing lake productivity. Measurements were made of standing crops of plankton, bottom fauna and fish as well as hypolimnial oxygen deficits, sedimentation rates and gross primary productivity. Standing crops of plankton appeared related to oxygen deficits and perimeter to area ratios. Furthermore, total dissolved solid content correlated with gross primary productivity estimates based on Light and Dark Bottle techniques. Total dissolved solid content of lakes was not correlated with standing crops of plankton, bottom fauna or fish. Ranking of selected physical or chemical indices of productivity failed to agree with ranking based on standing crops or other biological measurements of productivity. A number of possible factors which interact to modify the expression of primary correlates of productivity are discussed. / Science, Faculty of / Zoology, Department of / Graduate
102

Natural salt licks as a part of the ecology of the mountain goat

Hebert, Daryll Marvin January 1967 (has links)
The role of natural earth licks in the ecology of the mountain goat (Oreamnos americanus (Blainville)) was studied during the summers of 1965 and 1966 in the Rocky Mountain Trench of southern B.C. The patterns of movements of the animals were determined as they used the licks and the vegetation, lick soils and blood serum were analyzed with respect to sodium content. The predicated use of licks as suggested by other workers involves the idea that sodium may be the attracting element. The present study examined seasonal and differential patterns of movement, along with periodicity of use, in order to determine the resultant interplay of animal movement and sodium and water content of the vegetation. The goat encounters such additional risks as predation, parasitism, hunting and joint use while using the lick seasonally. Since the goats use the lick differentially in time, each sex is affected to a different degree by the above factors. Differential use also produces characteristic patterns of grouping and molting. Periodicity of use occurred mainly in the afternoon, although distance travelled and complexity of the lick may affect time of entry, length of stay and group size. The frequency of use differed at each lick, with the average time of use by an individual being one to three weeks. Environmental factors such as temperature and weather appear to regulate the movement to and from the lick. Analysis of the vegetation revealed that sodium was extremely low and that potassium was present in sufficient quantities to meet the requirements of the animal. No significant trends were found to exist from spring to fall or due to changes in elevation, as far as sodium and total ash were concerned. Observations indicated that animals select certain licks over others and select sites within a lick. These high licking sites were shown to have a higher sodium content. Newly established licks had a higher sodium content than did old licks, however, highly preferred sites were not always higher in calcium, phosphorus or cobalt. A normal range of serum sodium values was established for the goat but due to the regulatory function of the kidney, changes in serum sodium due to lick use could not be detected. Serum sodium decreased with age. A female with a kid had a low serum value. It appears that the level of deficiency causing the craving is not sufficient to show up in serum analysis. Animals died during trapping operations and a selenium deficiency was suspected. Gross symptoms approximated those attributed to white muscle disease and the vegetation contained selenium in amounts which are known to cause this myopathy. / Science, Faculty of / Zoology, Department of / Graduate
103

Some aspects of the population dynamics of the mountain pine beetle, Dendroctonus ponderosae in lodgepole pine forests of British Columbia

Peterman, Randall Martin January 1974 (has links)
Outbreaks of mountain pine beetle (Dendrcctonus ronderosae Hopk.) are common in lodgepole pine forests cf western North America. Characteristics of both the tark beetle and its host tree were compared using field replicates cf epidemic and endemic areas to test for any possible intrinsic differences between populations cf trees cr insects in these two different states. laboratory studies were conducted on beetle dispersal characteristics and cn effects of attack density and female parent size on beetle reproductive success and offspring size. Results are as follows: Trees in outbreak areas are older than in endemic regions, and trees of a given size and beetle attack density are more likely to be overcome and to permit successful beetle reproduction in epidemic than in endemic areas. However, tree spatial distributions, average attack densities and proportions of trees unsuccessfully attacked by beetles dc net differ consistently between epidemic and endemic areas. A method (in which blue-staining fungi were inoculated into trees) of measuring potential of trees tc resist mountain pine beetle was tested and found to be inadequate. Epidemic and endemic bark beetles did not differ consistently in dispersal, size, cr reproductive characteristics. However, early emerging beetles were larger than late emergers and females had a larger coefficient of variation in size than males. Field and laboratory data shew that the number of offspring emerging per parent decreases with increasing attack density. Breeding experiments further indicated that, 1) small female parents produce fewer and smaller offspring than large females, 2) small female parents produce female offspring with more strongly bimcdal size distributions than large females, and 3) high parental attack densities result in smaller offspring. Dispersal studies on the insect using chemical extracts of lodgepole pine bark showed that early emerging beetles are more likely to respond positively to tree chemicals than late emergers with the same flight history. Increasing lengths of flight increase female but not male responses to these chemicals. Evidence from a simulation model is presented tc support the hypothesis that the age at which lodgepcle pine normally becomes susceptible to mountain pine beetle attack is clcse to the age at which certain tree fitness measures are maximized. / Science, Faculty of / Zoology, Department of / Graduate
104

A pluralistic, socio-ecological approach to understand the long-term impact of mountain conservation: a counterfactual and place-based assessment of social, ecological and hydrological change in the Groot Winterhoek Mountains of the Cape Floristic Region

Holden, Petra Brigitte 24 August 2018 (has links)
The problem: For protected areas to remain relevant, we need to understand their impact on a wide set of conservation objectives and environmental outcomes. We also need to evaluate how this influence relates to the socio-ecological environment within which they occur. This is a complex endeavour requiring a pluralistic approach, which draws on a wide range of interdisciplinary fields. Research question: This thesis addresses the following question: What effects do mountain protected areas have on ecosystem services over time and how does this influence relate to broader socio-economic and ecological drivers of landscape change? Aim and objectives: I use a pluralistic, socio-ecological framing to assess the impact of ~40 years of mountain protection, drawing on comparisons of ~30 and ~40 years before and after protection respectively, with an adjacent area of similar terrain informing scenarios of counterfactual conditions. I also investigate what types of values (economic and intrinsic) are important when determining the impact of mountain protected areas. Thesis approach and methods: I operationalise the concepts of socio-ecological systems, ecosystem services, land use transitions and counterfactuals to investigate socio-ecological change and how it relates to protected area impact in the Groot Winterhoek, a mountain catchment in the south-western Cape of South Africa. This mountain catchment is important for regional water supplies for agricultural and domestic uses and falls in the Cape Floristic Region, a global biodiversity hotspot. It is comprised of privately owned mountain wildlands and a wilderness-protected area, known as the Groot Winterhoek Wilderness Area, established in 1978 (gazetted in 1985) which forms part of the Cape Floristic Region World Heritage Site. I combine methods from social science, ecology, environmental geography, geomatics and hydrology to understand the history of land use and cover (land use/cover) and associated ecosystem service trade-offs, how they are perceived by landowners as well as their wider impact on the region. Specifically, I assess the impact of protection on land use/cover, vegetation, fire and water flows over the last ~50 years, by comparing and contextualising results of change within the protected area to alternative scenarios of “no protection” (the counterfactual conditions). Vegetation and land use/cover change inside the protected area were determined respectively using 72 repeat terrestrial photographs and vegetation surveys, and an analysis of orthorectified aerial imagery. Methods used to construct the counterfactual scenarios of mechanisms (e.g. changes in land use/cover) that would likely drive vegetation changes inside the protected area included: i) 60 repeat surveys and in-depth interviews with landowners adjacent or proximal to the protected area owning unprotected land of similar terrain to the protected area; and ii) land use/cover change analysis of orthorectified aerial imagery of adjacent unprotected land of similar terrain before and after protected area establishment. 4 This latter information was used to understand the role of the protected area in driving vegetation changes inside the protected area. Social, biophysical and remote sensing results were directly used to parameterise land use/cover components of a hydrological model to determine the influence of protection on water flows. Specifically, water flows were simulated for the current state of the environment inside the protected area as well as for several counterfactual scenarios i.e. the alternative land use/cover scenarios of “no protection”. These counterfactual scenarios included land use/cover at two-time steps of ~30 and ~8 years before protection and one-time step ~40 years after protection both inside and outside the protected area. Results: Long-term change in ecosystem service use outside the protected area on privately owned land of similar terrain to inside the protected area (Section 3): Over the last ~50 years, outside the protected area, there was a shift from livestock-based, subsistence agriculture and small-scale farming to a diversified set of ecosystem service uses. The combined area of grazing and wildflower harvesting declined by 39%, while the number of landowners using the mountains for personal nature-based recreation and ecotourism increased by 61% and 23% respectively. Agriculture intensified in suitable areas of mountain land with the number of landowners cultivating land increasing by 20%. Exogenous socioeconomic drivers associated with globalisation and economic growth were important causal mechanisms of land use change. Landowners valued mountain protection for intrinsic and non-use reasons (73-80% of landowners), including existence, bequest and option values, as well as for the indirect use of water supply (72% of landowners) in comparison with direct use reasons such as spiritual/cultural experiences and nature-based recreation inside the protected area (18 and 50% of landowners respectively). Personal, nature-based recreation outside the wilderness-protected area was associated with valuing the protection of mountain land for intrinsic and non-use reasons. Long-term vegetation change inside the protected area and plausible mechanisms driving vegetation change (Section 4): Inside the mountain protected area, fynbos vegetation cover increased on average between 11 and 30% and there were significant declines in bare ground and rock cover. In 5 accumulation and fire intensities. However, these latter changes in land use/cover also occurred outside the protected area (see results summarised for Section 3 above and Section 4 below) and therefore cannot be attributed to protected area establishment. Land use/cover and the influence on water flows inside the protected area compared to counterfactual scenarios of no protection (Section 5): Declines in grazing and changes to the fire regimes occurred regardless of the protected area boundaries. In the past, there was a high frequency of small, low intensity fires across the landscape, both inside and outside the protected area. More recently, fires have been actively suppressed and this resultsin the build-up of biomass and the development of extensive, high intensity fires which, under suitable conditions, burn large expanses of the mountain catchment. Hydrological modelling showed that a high intensity burning regime negatively affected streamflow regardless of protected area boundaries. Streamflow increased by more than 80% under high flow conditions and decreased by more than 40% under low flow conditions relative to an unburnt ‘natural’ scenario. Over the last 50 years there has also been a substantial increase in dams, buildings and roads and minor increases in cultivation outside the protected area. This has been avoided inside the protected area where these land use/cover classes declined. If the increase in these land use/cover types observed outside the protected area occurred inside the protected area this would have resulted in reductions in daily streamflow leaving the protected portion of the catchment. For example, outside the protected area reductions of 8% to 25% of streamflow were observed during mid and low flow conditions respectively, particularly during dry years, in comparison to a ‘natural’ scenario. In contrast, inside the protected area streamflow recovered from past conditions to more closely resemble the natural flow conditions of the catchment. Therefore, had the protected area not been established there would have been losses in streamflow from the catchment as well as an increase in the degree of fragmentation within this mountain area. However, with increased water storage and fragmentation outside the protected area has also come increased socio-economic opportunities such as employment and local opportunities for ecotourism and sustainable agriculture e.g. indigenous cut flows. This highlights the importance of maintaining various forms of land management systems (multifunctional landscapes) within mountain ecosystems but also the need to understand the sustainability of different land management system types. Determining appropriate land management systems for mountain areas should be based on a full understanding of the impacts on ecosystem service benefits and costs at local and regional levels between social groups both spatially and temporally. Broader significance: This thesis contributes to the conservation literature on two main fronts. Firstly, it contributes conceptually and theoretically to understanding the dynamics of ecosystem services in relation to mountain protection. Secondly, it contributes methodologically by using an inclusive, trans- and interdisciplinary research approach for evidence-based conservation at a place-based and landscape level. The study provides a case 6 study example of the positive impact that mountain protection has on water-related ecosystem services, notably by maintaining streamflow throughout high to low flow periods and during dry years. It also provides clear evidence that ecosystem service trade-offs do not remain constant over time and shows that intrinsic and non-use values are required when describing the importance of mountain protected areas. In terms of understanding the impact that protected areas have in mountain regions, the research shows that complex processes are at play that extend beyond the boundaries of a specific protected area in both time and space. Interactions between global and local drivers were found to be prominent causal mechanisms of socio-ecological change and ultimately determined the influence of mountain-protection on land use/cover, fire, vegetation and water-related ecosystem services. The thesis emphasises that counterfactual framings are necessary to understand and attribute the impacts of protected areas on environmental outcomes, however pluralism and socio-ecological approaches are critical to determine plausible counterfactual conditions. This thesis focused only on landowners adjacent and proximal to the protected area owning the majority of mountain catchment land of similar terrain. It is likely that multiple socioeconomic trade-offs have occurred between different social groups and generations at both local and regional levels. Understanding how the disadvantages and benefits of the impacts of protected areas are apportioned across the landscape and temporally is an aspect that requires future research. Central to this would be to fully consider how human well-being is influenced both upstream and downstream, including at regional levels, and between social groups and across generations. Considering the impact of protected areas on the full range of ecosystem services and linking this to societal preferences and perceptions should be incorporated into the overall goal of developing an evidence base for conservation. This is because it is both scientific evidence and societal change that can determine protected area persistence and thus long-term protected area impact.
105

"Which Nature?": A Case Study of Whitetop Mountain

Robertson, David P. 29 May 1999 (has links)
In light of the social construction of nature, "new" ecology, and the fact that neither nature nor science (as the systematic study of it) can tell us what the Earth should look like, it becomes evident that numerous (if not infinite) past, present and future natures exist from which society must select the nature or natures that become the goals of local environmental management. The challenge is to find themes or patterns that might help organize and discuss these many natures. It is not enough to say or to demonstrate that many natures exist. Society needs conceptual tools that help focus the discussion of "Which Nature?" on those that are possible and socially acceptable. This paper is an effort to identify and articulate some of these themes to see if they have power in helping structure public understandings of natural landscapes. Specifically, we are looking for natures that are evident in a larger national dialogue, reflect issues that are significant to the region where the nature being managed exists, and themes that have historic and place-specific qualities that can be found in local discourse about the place. Four different but closely related points of view fit this need: romanticism, ecotourism, pastoralism, and ecologism. These four "views of nature" are distinct and coherent "ways of seeing" evident in national, regional, and local discussions about nature and natural landscapes. Each promotes a unique range of "natural" conditions that will be more-or-less possible and acceptable in any particular place. In the following sections, I will first provide a general overview of the "natural" landscape of Whitetop Mountain and then describe how it is can be seen from each of the four alternative "views of nature." / Master of Landscape Architecture
106

The geology of the Rigaud Mountain, Quebec.

Greig, Stanley Copeland. January 1968 (has links)
No description available.
107

Planning Gone Hog Wild: Mega-Hog Farm in a Mountain West County

Sanders, Jeffrey Melvin 19 July 2007 (has links) (PDF)
Lacking the natural amenities “New West" counties, some rural communities have attempted to attract land use activities that are normally seen as undesirable. One example of these undesirable industries is the hog concentrated animal feeding operation, or CAFO. While a number of studies have explored the socio-economic and environmental aspects of hog farms, few studies have focused on the planning process and evaluated its effectiveness in dealing with the threats and challenges that a CAFO poses. This qualitative study used interviews, observations, public meeting minutes, and other written sources of data to evaluate whether or not a rural, western community, Beaver County, Utah, was able to successfully plan for one of the largest hog operations in the United States. The evidence suggested that the majority of planning efforts failed in the short-term, but were more successful in the long-term. Despite any relative success, the proposal generated intense controversy in the small community. Crucial to any planning achievement was the input and guidance provided by the state environmental agency. This research highlights the need for long-range planning as well as the importance of public participation in the planning process.
108

Understory vegetation response and nitrogen cycling following cutting of western juniper

Bates, Jonathan D. 07 June 1996 (has links)
Since the late 1880's western juniper has expanded in range and increased in density in sagebrush-bunchgrass, riparian, and forested plant communities of the Pacific Northwest. Succession to western juniper woodland has been shown to reduce the productivity and diversity of the understory component, result in concentration of soil nutrients beneath juniper canopies, and reduces soil moisture storage. This study assessed understory plant succession, soil nitrogen (N) cycling, litter decomposition, and soil moisture availability following cutting of a western juniper woodland on Steens Mountain, Oregon. Cutting of western juniper reduced below-ground competition for water and N, increasing soil moisture storage and N availability for understory species. Leaf water potentials were less negative, and N concentration and biomass in understory plants were greater in the cut treatment. Understory species responded to improved growth conditions with increased cover, biomass, density, and diversity. In 1993, total understory biomass and canopy cover were 870% and 300% greater, respectively, in the cut treatment than the uncut woodland. Understory succession was dominated by plants present on the site prior to cutting. Results indicated initial that bunchgrass densities of 2 plants/m2 were sufficient for perennial grasses to dominate following juniper cutting. Juniper cutting is an effective method for restoring the understory component in sagebrush rangelands that are currently dominated by western juniper woodland. Nitrogen availability was greatest in cut-interspace locations the first year following treatment and in cut-duff locations in the second year. Nitrification was lowest in cut-slash and woodland-duff locations, areas receiving fresh litter inputs and experiencing lower temperatures than interspace (cut and woodland treatments) and cut-duff locations. Decomposition of juniper litter was two times faster in the cut treatment, however the release of litter N occurred earlier in the woodland. Large inputs of N poor litter from cut juniper slash were hypothesized to have increased microbial demand for N, resulting in immobilization of litter N. Immobilization of litter N may be important in conserving N on sites following cutting. / Graduation date: 1997
109

Phonological form, morphological class, and syntactic gender : the noun class systems of Papua New Guinea Arapeshan /

Dobrin, Lise Miriam. January 1999 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Linguistics, August 1999. / Includes bibliographical references. Also available on the Internet.
110

The geology and ore deposits of the Mountain Queen area, northern Swisshelm Mountains, Arizona

Loring, William Bacheller, 1915-, Loring, William Bacheller, 1915- January 1947 (has links)
No description available.

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