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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.
231

Local topography is more important than climate as a determinant of regional alpine plant diversity in southwestern British Columbia

Baldwin-Corriveau, Katharine 04 September 2012 (has links)
Mountain ecosystems are considered highly sensitive to the impacts of climate change, and are experiencing a magnitude of change that far exceeds global averages, particularly with respect to increases in average temperature and precipitation. As such, scientists are predicting a rapid habitat reduction or even the loss of the coolest climatic alpine zones, thus threatening the continued survival of high elevation specialists. However, many of these ‘doomsday’ predictions are based primarily on models with coarse-resolution changes to atmospheric climate parameters, and do not take into account the potential buffering effects of other environmental gradients known to structure alpine plant communities, related to topography and soils. To assess the accuracy of predictions regarding the state of vulnerability of alpine plant communities to climate change, this thesis examined the relative importance of climate, topography and soils as determinants of regional alpine plant diversity for all species, as well as for forbs, graminoids and woody species separately, in alpine meadows of southwestern British Columbia. Through redundancy analyses and variation partitioning, results show that topography and soils are more important than climate as determinants of regional alpine plant diversity. Within these groups, elevation, slope, soil moisture and mean summer temperature were most significant. Interestingly, precipitation played only a small role, even though the study area spanned a precipitation gradient of over 1200 mm/year. The stronger influence of temperature, especially for woody species beta diversity, supports findings of shrub expansion in arctic-alpine systems. The lower importance of climate as a determinant of regional alpine plant diversity, especially for forbs, the dominant life form in alpine meadow ecosystems, suggests that these productive environments may be more resilient to on-going changes in atmospheric climate conditions than previously believed. / Graduate
232

An ecological study of the cerrado vegetation of South-Central Brazil /

Goodland, Robert J. A., 1939- January 1969 (has links)
No description available.
233

Assessing post-fire reseeding potential using Bureau of Land Management criteria in northeastern Nevada a spatial modeling approach /

Weigel, Timothy J. January 2007 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2007. / "August, 2007." Includes bibliographical references. Online version available on the World Wide Web.
234

Vegetation dynamics of the Menindee Lakes with reference to the seed bank /

Nicol, Jason . January 2004 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004. / "August 2004" Includes bibliography. Also available electronically.
235

Vegetation dynamics of the Menindee Lakes with reference to the seed bank

Nicol, Jason . January 2004 (has links)
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004. / "August 2004" Includes bibliographical references. Also available in print.
236

Support host selection of Lonicera japonica and its interaction with different environmental and biotic factors in Cameron Park, Waco, Texas

Gao, Song, Bratton, Susan. January 2008 (has links)
Thesis (M.S.)--Baylor University, 2008. / Includes bibliographical references (p. 103-107).
237

Effects of abiotic factors and cattle grazing on gypsum outcrop plant communities in the Cimarron Gypsum Hills, northwestern Oklahoma /

Rice, Kristi Dawn. January 2008 (has links) (PDF)
Thesis (M.S.), Biology--University of Central Oklahoma, 2008. / Includes bibliographical references (leaves 98-104).
238

A landscape-scale analysis of vegetation recovery at Mount St. Helens /

Lawrence, Rick L. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 1998. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.
239

Investigation on selected biotic and abiotic factors in the maintenance of the "fairy circles" (barren patches) of southern Africa

Joubert, Angelique. January 2008 (has links)
Thesis (M.Sc.)(Plant Science))--University of Pretoria, 2008. / Includes bibliographical references.
240

Developments of roots and shoots of certain deciduous tree seedlings in different forest sites

Holch, Arthur Everett, January 1931 (has links)
Thesis (Ph. D.)--University of Nebraska, 1930. / Cover title. "Reprinted from Ecology, vol. XII, no. 2., April, 1931." "Literature cited": p. 297-298.

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