• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 55
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 78
  • 78
  • 30
  • 21
  • 18
  • 12
  • 11
  • 9
  • 7
  • 7
  • 7
  • 7
  • 6
  • 6
  • 5
  • 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.
11

Appraisal of methods used to study species diversity and their application in an analysis of pyric succession.

Venning, J. January 1974 (has links) (PDF)
Thesis (B.Sc. Hons.1975) from the Dept. of Botany, University of Adelaide.
12

Productivity and herbivory in high and low diversity tropical successional ecosystems in Costa Rica

Brown, Becky Jean, January 1982 (has links)
Thesis (Ph. D.)--University of Florida, 1982. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 249-265).
13

An Ecological Study of an Oak Hickory Association

Mizer, Orrin J. January 1947 (has links)
No description available.
14

An Ecological Study of an Oak Hickory Association

Mizer, Orrin J. January 1947 (has links)
No description available.
15

Primary plant succession on the Twin Glacier foreland, Alexandra Fjord, Ellesmere Island, Canadian high Arctic

Jones, Glenda A. 05 1900 (has links)
Primary plant succession was examined on the foreland of the retreating Twin Glacier at Alexandra Fjord, Ellesmere Island. The position of the glacial front was monitored directly from 1980 to 1995 (except 1986-1991), and airphotos show the position of the glacier in 1959. Hence, there was an excellent opportunity to study primary succession where there was adequate chronological control. Presently, a well preserved pre-Little Ice Age plant community and organically rich (paleo) soil are being released from the Twin Glacier, in addition to glacio-fluvial sediments, rendering this foreland study unique. A terrain age scheme was developed using direct retreat measurements, airphotos and Salix aging. The relationship between the clump diameters of Luzula confusa and terrain age was determined to provide an alternative to lichenometry. Vegetation cover was assessed in 1994 and 1995 using a stratified random design. TWINSPAN and canonical correspondence analysis (detrended and non-detrended) were used together to examine vegetation patterns in relation to environmental variables. Soil seed bank and seed rain patterns were examined in relation to the above-ground vegetation. The seed bank was sampled in 1994, including samples from paleo-soil and glacio-fluvial sediment. To assess the fall-winter seed rain, seeds were collected between mid-August 1994 and early June 1995, using seed traps (artificial turf). Winter seed rain was sampled by collecting snow-core samples in early June 1995. Terrain age accounted for most of the variation in species composition over the study area. By directional-replacement, the succession followed four main stages of dominance in 44+ years: mosses —> graminoid-forb —> deciduous shrub-moss —> evergreen dwarf-shrubmoss. There was little difference in the successional sequences exhibited by the vegetation growing on the paleo-soil compared to that growing on the glacio-fluvial sediment. The relationship between the Luzula confusa clump diameters and terrain age was logarithmic. Luzula confusa dominated the above-ground vegetation, as well as, the germinable seed bank and seed rain. The average germinable seed bank, fall-winter seed rain and winter seed rain densities were 367 ± 32, 384 ± 47 and 180 ± 53 seeds/m2, respectively. The seed bank was significantly positively correlated with the above-ground vegetation cover for all species combined, Luzula confusa (monocotyledons), dicotyledons and Papaver radicatum. There was a significant positive correlation between the fall-winter seed rain and the above-ground vegetation cover for Luzula confusa. No difference was detected in seed bank density between the paleo-soil and the glacio-fluvial sediment. However, the total vegetation cover was significantly higher on the paleo-soil. The relationship determined between Luzula confusa clump diameters and terrain age appears to be a valuable alternative to lichenometry on the Twin Glacier foreland. Although the results showed that directional-replacement is possible in high arctic environments, this mode of succession is likely atypical of such environments; the Twin Glacier foreland is located in one of the very few polar oases in the Queen Elizabeth Islands. The positive correlation of the above-ground vegetation with the seed bank and fall-winter seed rain suggests that colonization is largely constrained by seed availability. The winter seed rain appears to be relatively important on the Twin Glacier foreland. The higher vegetation cover on the paleosoil versus the glacio-fluvial sediment suggests, at least for some species, that the former provides conditions more favourable for establishment and growth than the latter.
16

Edaphic controls over succession in former oak savanna, Willamette Valley, Oregon /

Murphy, Meghan Suzanne, January 2008 (has links)
Thesis (M.S.)--University of Oregon, 2008. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 84-87). Also available online.
17

Palynological records of forest disturbance and development in the Mountain Meadows watershed, Mt. Rainier, Washington /

Sugita, Shinya, January 1990 (has links)
Thesis (Ph. D.)--University of Washington, 1990. / Vita. Includes bibliographical references (leaves [174]-190).
18

Intervention in succession a method for applying succession theory in landscape design with a focus on vegetation succession in western Washington /

Horton, Lindsey, January 2005 (has links) (PDF)
Thesis (M.S. in landscape architecture)--Washington State University. / Includes bibliographical references.
19

Modelling early plant primary succession on Mount St. Helens

Marleau, Justin Normand. January 2009 (has links)
Thesis (M. Sc.)--University of Alberta, 2009. / Title from PDF file main screen (viewed on Oct. 16, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Ecology, Biological Sciences, University of Alberta." Includes bibliographical references.
20

Seed rain and selected species germination and growth trials : implications for natural and augmented revegetation of post-dam Elwha River floodplain and reservoir sediments /

Michel, James T. Helfield, James M. January 2010 (has links)
Thesis (M.S.)--Western Washington University, 2010. / Includes bibliographical references (leaves 31-36). Also issued online.

Page generated in 0.0989 seconds