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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.
381

Biophysical and Climate Analysis of the Mountain Pine Beetle (Dendroctonus ponderosae) Infestations in the Crown of the Continent, 1962 to 2014

Garza, Mario Nicholas 22 February 2017 (has links)
Mountain pine beetles (Dendroctonus ponderosae) are native insects that have decimated millions of hectares of mature pine (Pinaceae) forests in western North America. The purpose of this study is to investigate biophysical and climatic correlates of Mountain Pine Beetle (MPB) insect outbreaks in the Crown of the Continent Ecosystem (CCE) from 1962 to 2014 using Aerial Detection Survey (ADS) and climate data. Specific objectives were: 1) to develop statistical models to determine how selected biophysical correlates (slope, aspect, elevation, and latitude) and 2) to understand how local and global climate variables relate to the extent of the MPB infestations in the CCE, and 3) to contextualize the results of the models with historical climate data. Overall, the major findings of this study are: 1) despite its limitations, the ADS data seems suitable for analysis of beetle damage with respect to climate and topographic factors, on a regional scale, 2) there appears to be a link between local biophysical factors and winter precipitation and TPA within the CCE, and 3) a combination of a negative-phase PDO and La Niña is important in forecasting a decline in MPB spread, during a given year. This study is the first, to our knowledge, to explore spatio-temporal patterns of MPB outbreaks using biophysical factors, and both local and global climate variables, over a fifty-year timespan in the CCE. In the future, additional geospatial analyses may enable a landscape assessment of factors contributing to variability of MPB infestation and damage as this insect continues to spread. / Master of Science / Mountain pine beetles (Dendroctonus ponderosae) are a native insect that has decimated millions of hectares of mature pine forests in western North America. The purpose of this study was to investigate, using GIS-derived variables, biophysical and climatic factors that have influenced past mountain pine beetle insect outbreaks, as evident by beetle-induced tree mortality in the Crown of the Continent Ecosystem (CCE) from 1962 to 2014. Specific objectives of this study were to determine how selected biophysical variables (slope, aspect, elevation, and latitude), regional climate variables (temperature, precipitation, and drought) and global climate oscillations (ENSO, PDO, NAO, AO, and PNA) relate to bark beetle infestations in the Crown of the Continent Ecosystem from 1962 through 2014, as measured by aerial surveyrecorded tree mortality. We sought to contextualize the results of the statistical models with historical data to further understand the relationship between increases and decreases of tree mortality by comparing these trends to geopotential height and sea-surface temperatures that may influence CCE climate. Our work revealed first, that while the aerial survey data has important limitations, overall it is a useful dataset for analyzing historical spatio-temporal patterns of insect infestations. Second, there appears to be a link between local biophysical factors, such as latitude, elevation, and winter precipitation (as opposed to global climate factors) and tree mortality within the CCE. Local climate analysis revealed the importance of winter precipitation to be the biggest influence of MPB decrease or increase along with lower geopotential heights during a decline in MPB spread over the CCE. Finally, a combination of a negative PDO and El Niño was important in forecasting a decline in MPB spread, as shown by damage, during a given year. This is the first study to use aerial survey data in a geospatial analysis incorporating biophysical variables for the US portion of the Crown of the Continent Ecosystem. Additionally, this study is unique to explore the potential relationship between global teleconnections and regional climate in the CCE area, and the spatio-temporal extent of mountain pine beetle infestations.
382

A test of a mineralogic mapping technique in the Italian Mountain area, Colorado

Truebe, Henry A. (Henry Albert) January 1982 (has links)
No description available.
383

Ecological aspects and conservation of the invertebrate fauna of the sandstone caves of Table Mountain, Cape Town.

Sharratt, Norma Joan. 23 December 2013 (has links)
No abstract available. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1998.
384

The North Break Zone of the late Precambrian Otavi carbonate platform sequence in Namibia: stratigraphic setting, petrography and relationship with Tsumeb Cu-Pb-Zn deposit

Theron, Salomon Johannes 24 April 2014 (has links)
M.Sc. (Geology) / The main objective of this study was to characterize the North Break Zone of the Otavi Mountain Land, Namibia in terms of stratigraphy and petrography and to investigate its relationship with the Tsumeb ore body and other mineralized prospects in the immediate vicinity of Tsumeb. The Late Proterozoic Otavi carbonate platform sequence is famous for its base metal deposits. The North Break Zone is a stratabound zone of sporadic mineralization, brecciation and silicification occurring in the lower part of Iithozone T6 of the Hoffenberg Formation (Tsumeb Subgroup). It intersects the pipe-like Tsumeb Cu-Pb-Zn-Ag ore body at a depth of about 900m below surface. Where the North Break Zone intersects the Tsumeb ore body large massive ore associated with calcitized dolomite, dolomite breccia as well as feldspathic sandstone lenses occur. These features extend along strike and dip outside the normal dimensions of the Tsumeb ore body. The genesis of the Tsumeb ore body is poorly understood. The conventional model is that meteoric fluids circulated through the so-called North Break Zone paleo-aquifer, dissolving carbonate and giving rise to solution collapse and eventually the creation of the Tsumeb karst pipe. However, no direct evidence is available to support this model. This study was devised to critically evaluate the relationship between the North Break Zone and formation of the Tsumeb ore body. The study entailed field mapping, detailed sampling of the stratigraphic sequence and ore bodies, white light, reflected light, UV/blue light and cathodoluminescence petrography. Cathodoluminescence proved to be the most effective petrographic tool for differentiating various carbonate phases. The North Break Zone is defined as a 10 to 14m thick chert free oolitic to intraclastic dolomitic grainstone, stromatolite and mudstone unit, in which discontinuous lenses of mineralized secondary quartz are present. It is interbedded with dark grey cherty micritic dolomite of Lithozone T6 of the HOffenberg Formation. Minor calcification, Cu-Pb-Zn mineralization and manganese and iron enrichment are associated with the quartz-rich bodies. The mineralized quartz bodies are only present up to 2.5km to the west and 2.6km to the east of the Tsumeb ore body. The petrographic study indicated that 1) the epigenetic sequence of carbonate alteration, precipitation of new carbonate phases and mineralization is virtually identical in all Cu-Pb-Zn occurrences and 2) that the mineralization is closely associated with Mn-bearing brightly luminescent (CL) carbonates. Earlier Cu-Pb-Zn sulphide mineralization is associated with Mn-bearing bright red luminescent sparry dolomite (dolomite IIIB). Late stage Cu-arsenate, oxide and silicate mineralization is associated with an episode of Mn-bearing bright yellow luminescent calcite (calcite II) which also causes dolomitization of the associated dolomites. A very simple paragenetic model of mineralization is proposed. The earliest is defined by pre-mineralization calcite (calcite I) vein formation with associated dolomitization. This phase is followed by deposition of kerogen luminescent Mn-bearing dolomite IIIB - quartz and Cu-Pb-Zn sulphides representing the main mineralization event. It is followed by a late mineralization event composed of Mn-bearing calcite (calcite II) with associated Cu-arsenates, oxides and silicates. Supergene alteration is represented by the precipitation of very late stage non-luminescent Mn and Fe-poor calcite (calcite III) and quartz without any associated Cu-Pb-Zn mineralization. The sequence of mineralization is explained by the evolution of a single hydrothermal fluid, from relatively cold to hot and then back to cold, during a major period of fluid migration through the carbonate platform sequence. The North Break Zone probably never acted as a paleo-aquifer for fluids that formed the Tsumeb ore body. Rather hydrothermal fluids moved from the Tsumeb ore body into the North Break Zone. Hydrothermal fluids may have been derived from the Damara orogen to the south of Tsumeb during a period of tectonic loading and thrust deformation.
385

Historie cyklistiky na horských kolech na Vimpersku - od roku 1989 do současnosti / History of mountain biking in Vimperk- from 1989 to the present

Pomezný, Lukáš January 2021 (has links)
IN ENGLISH The work deals with the history of mountain bike in Vimpersko from 1989 to the present. Major cycling events, prominent racers, organizers and founders of a mountain bike section in Vimpersko should appear in the work. The main aim of this work is to investigate and record the arrival of a mountain bike in Vimpersko from 1989 to the present. Partial objectives include recording the main characters associated with the emergence of mountain bike races and a section in Vimperk and linking the topic with the history of cycling in the Czech Republic. The main method of work is the historical method enriched with interviews with the main actors of mountaine biking in Vimpersko.
386

Fundamentals of Mountain Resort Base Village Design: A Critical Review of Existing Resort Developments with Recommendations for Future Development Practices

Harding, Bryan P. 01 May 2006 (has links)
The North American ski industry has grown over the past century from a small, family-owned and -operated industry, to a multi-billion dollar industry dominated by corporate management organizations. The rise of corporate resort ownership has led to the trend of the construction base village developments at ski resorts around the country to attract guests, and therefore revenue, to their resorts. Though many base villages have been very successful in attracting skiers, examples of poor landscape architectural design practices abound in the industry. This study examines several design elements considered to be the "fundamental elements of designed space," applies these elements to base village design throughout the country, critically examines their implementation in built examples, and presents suggestions and recommendations for future mountain resort base village design practices.
387

Transnational Amenity Migrants in the Mountainous Regions of the Republic of Georgia: Motives to Move, Adaptation Strategies, Integration into the Local Community

Davlianidze, Natalia 26 May 2021 (has links)
No description available.
388

Geology, Geochemistry, and Geochronology of the Nathrop Volcanics: A Comprehensive Look at the History and Formation of Ruby and Sugarloaf Mountains

Nelson, Jennifer 21 September 2021 (has links)
No description available.
389

Geology and Eruptive History of the Late Oligocene Nathrop Volcanics, Central Colorado Volcanic Field

Emery, William Daniel 11 March 2011 (has links)
No description available.
390

A residence for Tryon mountain

Walters, Herschel Gray January 1953 (has links)
This thesis has three objectives. First, to present the findings of an investigation made to determine the conditions of the selected mountain site and to familiarize myself with family living requirements. Second, to employ these findings in an organized design to satisfy all architectural and family requirements. Third, to present a detailed design of the residence which shall be designated “A Residence for Tryon Mountain.” / Master of Science

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