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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.
131

The flora and plant communities of Botany Glen

Stonehouse, Amanda L. January 2003 (has links)
Botany Glen, The James S. Wilson Memorial Sanctuary, is an 18 hectare (45 acre) forested tract located in Grant County, Indiana, adjacent to the Mississinewa River. Botany Glen is an important natural area in east central Indiana due to its relatively small size and high diversity.The flora documents 331 species and varieties of vascular plants representing 241 genera and 90 families; 158 species are recorded for the first time in Grant County. Of the 331 species listed, 67 (or 20%) are exotic. Most of these exotics have failed to penetrate the interior of the forest.Permanent monitoring plots were established in dry upland forest, floodplain forest and secondary successional forest. Data were collected from overstory, understory and herbaceous plant layers in these plots. Analysis of these data and information from the floristic inventory were utilized to describe the structure and composition of three primary plant communities. Baseline data and procedures were established for future study of this property. / Department of Biology
132

An ecological study of the plant communities and degraded areas of the Highveld National Park, North West Province, South Africa / Mahlomola Ernest Daemane

Daemane, Mahlomola Ernest January 2007 (has links)
The objectives of the study were to identify, classify, describe and map the plant communities in the proposed Highveld National Park, including the degraded Spitskop areas. Vegetation sampling was done by means of the Braun-Blanquet method and a total of 108 stratified random relevés were sampled. A numerical classification technique (TWINSPAN) was used and the result was refined by Braun-Blanquet procedures. The final results of the classification procedure were presented in the form of phytosociological tables and twelve plant communities were described. For indirect ordination, a Detrended Correspondence Analysis (DCA) algorithm was applied to the data set to confirm the phytosociological association and to assess floristic relations between communities. For direct environmental gradient analysis the Canonical Correspondence Analysis (CCA) was applied to the data using the CANOCO software program. The plant communities were combined into six management units based on similarities regarding vegetation composition, habitat, topography and soil characteristics. Characterization of land degradation was done by grouping erosion into different classes and different degrees of severity. Degraded areas in need of rehabilitation and restoration were identified and described. Recommendations were made with regard to rehabilitation and monitoring of all degraded areas in the HNP. / Thesis (M.Sc. (Botany))--North-West University, Potchefstroom Campus, 2008.
133

Vegetation community characteristics and dendrochronology of whitebark pine (Pinus albicaulis) in the southern Coast Mountains, British Columbia

Carlson, Kimberly 21 August 2013 (has links)
Whitebark pine (Pinus albicaulis) is an endangered keystone tree species growing at the highest elevations in the mountain ranges of western North America. Across its range, whitebark pine is faced with a number of threats including fire suppression, mountain pine beetle, white pine blister rust, and climate change. Climate change is perhaps the greatest threat facing the species, yet it is the least understood. Most studies rely on model predictions and only look at the impacts on whitebark pine itself, not taking into consideration the other bird, mammal, and plant communities that are associated with it. In order to assess the potential effects of climate change on whitebark pine communities in the southern Coast Mountains of British Columbia, this thesis examined the vegetation associations and climate controls currently shaping the communities. My results showed that whitebark pine is growing in the open away from other subalpine tree species. This suggests that whitebark pine is not facilitating other subalpine tree species, contrary to what has been shown in the Rocky Mountains. Evidence of a distinct suite of understory vegetation associated with whitebark pine is weak and inconclusive. Differences in understory vegetation appear to be mainly due to site differences in climate, soils, and topography. Age distributions constructed from tree cores revealed that whitebark pine decline at lower elevation sites may be due to successional advancement to subalpine fir, and subalpine fir is currently encroaching into higher elevation sites. A dendrochronological assessment revealed that winter conditions, including snowpack, temperature, and the Aleutian Low Pressure Index (ALPI) were the most limiting to whitebark pine growth at high-elevation sites, but biotic factors including disease and competition appear to be more important than climate in determining annual ring growth at lower elevation sites. Bootstrapped correlations between annual ring widths and snowpack records showed that tree responses to fluctuating snowpack have changed over time. For most of the 20th century, low snowpack periods were associated with greater annual growth. Since around 1970, when the snowpack levels dropped below anything previously recorded for the area, annual tree growth has been reduced. It appears that these high elevation tree species require a balance between too much snow (shorter growing season) and too little snow (reduced protection from harsh winter conditions). Climate change models for the area predict drastically reduced snowpack in the coming decades. If snowpack continues to drop, as it has since 1970, it will likely lead to severe impacts on whitebark pine growth in the southern Coast Mountains. / Graduate / 0329 / carlsonkim@hotmail.com
134

Plant species habitat reversals in the upper South-East of South Australia /

Sparrow, Ashley. January 1984 (has links) (PDF)
Thesis (B. Sc. Hons)--University of Adelaide, 1984. / Includes bibliographical references (leaves 54-57).
135

Introduced plant invasion in small remnants of native vegetation /

Oppermann, Alison. January 1992 (has links) (PDF)
Thesis (M. Env. St.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1993. / Includes bibliographical references (leaves 97-104).
136

Summer feeding behaviour of reindeer : a hierarchical approach /

Mårell, Anders, January 2006 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniversitet, 2006. / Härtill 4 uppsatser.
137

The effects of elephants at low densities and after short occupation time on the ecosystems of the Eastern Cape Province, South Africa /

Parker, Daniel Matthew. January 2008 (has links)
Thesis (Ph.D. (Zoology & Entomology)) - Rhodes University, 2008.
138

A plant association classification for McDonald-Dunn Forest /

Hubbard, Connie J. January 1991 (has links)
Thesis (M.S.)--Oregon State University, 1991. / Includes mounted photographs. Typescript (photocopy). Includes bibliographical references (leaves 134-143). Also available on the World Wide Web.
139

The contribution of spawning pacific-salmon to nitrogen fertility and vegetation nutrition during riparian primary succession on an expansive floodplain of a large river

Morris, Michael Roger. January 2008 (has links)
Thesis (PhD) University of Montana, 2008. / Title from author supplied metadata. Contents viewed on May 19, 2010. Includes bibliographical references.
140

Using distance-similarity relations to evaluate the importance of neutral ecological drift

Link-Perez, Melanie A. January 2005 (has links)
Thesis (M.S.)--Miami University, Dept. of Botany, 2005. / Title from first page of PDF document. Document formatted into pages; contains [1], iv, 109 p. Includes bibliographical references (p. 36).

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