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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.
21

Beiträge zur Ökologie der Felsflora Untersuchungen aus dem Curfirsten- und Sentisgebiet /

Oettli, Max. January 1904 (has links)
Thesis--Zürich. / "Arbeit aus dem botanischen Museum des eidgenössischen Polytechnikums in Zürich." "Separatabdruck aus dem Jahrbuch der St. Gallischen Naturwissenschaftlichen Gesellschaft, 1903." "Auch erschienen als: drittes. Heft der Botanischen Exkursionen und pflanzengeographischen Studien aus der Schweiz." Includes bibliographical references (p. 169-171).
22

An invasive macrophyte creates cascading ecosystem effects through suppression of a native isoetid

Urban, Rebecca Anne. January 2008 (has links)
Thesis (Ph. D.)--State University of New York at Binghamton, Department of Biological Sciences, 2008. / Includes bibliographical references.
23

Economic and social impacts of restoration : a case study of the Great Basin Region /

Satyal, Vijayanand H. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 95-100). Also available on the World Wide Web.
24

Experimental assessment of a gateway invader : how yellow bush lupine (Lupinus arboreus) facilitates the loss of native dune vegetation /

Cipra, Jane Ashdown. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 36-38). Also available via Humboldt Digital Scholar.
25

Makrophyten und Phytobenthos: Indikatoren für den ökologischen Gewässerzustand

Gutowski, Antje, van de Weyer, Klaus, Hofmann, Gabriele, Doege, Angela January 2011 (has links)
Rund 3.000 Arten zur Beschreibung des ökologischen Zustandes von Gewässern nach den Vorgaben der Europäischen Wasserrahmenrichtlinie wurden bisher in Sachsen erfasst. Die größte Gruppe stellen Wasserpflanzen einschließlich Algen dar. Die reich bebilderte Broschüre stellt eine Auswahl in Sachsen vorkommender Wasserpflanzen und am Gewässerboden lebender Algen vor und gibt Einblick in eine faszinierende Unterwasserwelt. Sie ermöglicht wasserwirtschaftlichen Praktikern und interessierten Naturschützern einen Einstieg in die Interpretation des ökologischen Gewässerzustands.
26

Comparison of bare root vs. potted plants, species selection, and caging types for restoration of a prairie wetland, and quantitative analysis and descriptive survey of plant communities and associations at Lewisville Lake Environmental Learning Area (LLELA), Lewisville, TX

Buckallew, Robin Randolph. Dickson, Kenneth L., January 2007 (has links)
Thesis (Ph. D.)--University of North Texas, May, 2007. / Title from title page display. Includes bibliographical references.
27

Regeneration and growth of several canopy tree species in the Maya Forest of Quintana Roo, Mexico : the role of competition and microhabitat conditions /

Sorensen, NaDene S. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 204-236). Also available on the World Wide Web.
28

Variação de traços funcionais que estruturam comunidades vegetais em restingas / Plant traits variation that structured communities in restingas

Lins, Lays Klécia Silva 31 March 2017 (has links)
Functional trait-based approaches are increasingly used in plant ecology to analyse the environmental filtration observed in environmental gradients. Such analyzes allow a quantification of the functional response of plant communities to changes occurring in a gradient, responding to abiotic and biotic drivers. Evidence suggests that intraspecific variation, due to phenotypic plasticity or genetic diversity and a difference in the composition of the species in question, should play a crucial role in driving the relationship of trait values in community vs. environment. Based on this, this dissertation presents an evaluation of the variation of functional traits of plant species in response to environmental filters in Restingas slopes of the South Coast of Alagoas as well as a contribution of the instraespecific variation and the turnover of the species in the gradient. For this, we measured 11 functional traits in Restinga species along a gradient by transects. We grouped plant species according to zones of gradient (zone a to zone c) and zone d (flood) and compared individual’s traits by ANOVA. Our second analysis partitioned the contributions of species turnover and intraspecific variation to among-site variation in functional traits. Significant differences were found between averages of traits in the zones. Evaluating the influence of species turnover and intraspecific variation on the average of each characteristic found in the zone, a decomposition of the total variation showed that the turnover of the species represents a greater proportion of the total variation of the characteristics in an intraspecific variation. Our results reveal that a community assembly is limited by environmental filters. / Recentes estudos em traços funcionais têm focado em análises para detecção da filtragem ambiental observada em gradientes ambientais. Tais análises permitem a quantificação da resposta funcional das comunidades de plantas às mudanças ambientais que ocorrem num gradiente, respondendo a “drivers” abióticos e bióticos. Evidências sugerem que a variação intraespecífica, decorrente da plasticidade fenotípica ou da diversidade genética e a diferença na composição das espécies em gradientes (isto é, o turnover da espécie), deve desempenhar um papel crucial na condução das relações valores de traços na comunidade vs ambiente. Baseado nisso, esta dissertação apresenta uma avaliação da variação de traços funcionais de espécies de plantas em resposta a filtros ambientais em gradientes de Restingas do Litoral Sul de Alagoas bem como a contribuição da variação instraespecífica e do turnover das espécies na comunidade. Para tanto, foram medidos 11 traços funcionais em espécies de Restinga ao longo de um gradiente edáfico por meio de transectos. As espécies foram agrupadas de acordo com as zonas do gradiente e os valores médios de traços funcionais por zona foram comparados por meio de ANOVA. Depois, foram calculadas as contribuições do turnover de espécies e da variação intraespecífica nas respectivas zonas. Foram encontradas diferenças nas características funcionais das espécies entre as zonas. Avaliando a influência do turnover de espécies e da variação intraespecífica sobre as médias de cada característica encontrada na zona, a decomposição da variação total mostrou que o turnover das espécies representou uma maior proporção da variação total da característica em comparação com a variação intraespecífica. Nossos resultados revelam, então, que a montagem da comunidade é limitada por filtros ambientais.

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