Thesis (Ph. D.)--University of North Texas, 1999. / Title from PDF title page (viewed on Dec. 10, 2004). Includes bibliographical references (p. 259-272).

Thesis (Ph. D.)--University of Oulu, 1988. / List of original papers of the author. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.

Thesis (M.Sc.)(Botany)--University of Pretoria, 2006. / Includes summary. Includes bibliographical references. Available on the Internet via the World Wide Web.

Thesis (M.S.)--University of Wisconsin--Stevens Point, 2006. / Includes bibliographical references (leaves 76-82).

Quantitative and qualitative vegetation and environmental data from one-hundred-fourteen sample plots were used to characterize and evaluate ecological relationships and dynamics previously little known for the Subalpine Mountain Hemlock Zone on the southwestern British Columbia mainland. Environmental analyses, presented in detail, include the description of thirty-six kinds of soil representing several major categories. From the analytical data, each sample plot consists of a single set of values representing local historically developed variations and patterns of vegetation, soil, microclimate and topography within the biogeoclimatic zonal concept of Krajina (1962). A combined vegetation-environment synthesis resulted in the characterization of ecosystematic units at several levels of generalization (zone, subzone, order, alliance, association, subassociation and variant) within the following classification scheme: (A) Parkland Subzone i) Chionophilous (Schneetalchen) units, with snow -duration of at least 9 months 1) Vegetation of unstable sheet-wash slopes or hamada-like surfaces 2) Sedge vegetation of semi-terrestrial basin habitats ii) Moderately chionophilous units with snow duration averaging between 8 and 9 months 1) Herbaceous vegetation of stream-edge, spring-line or semi-terrestrial habitats 2) Heath-like or low shrub vegetation of terrestrial mesic to hygric habitats iii) Chionophobous forested units with snow duration averaging about 8 months or less 1) Mesic habitats 2) Moderately dry habitats (B) Forest Subzone i) Forested units lacking a seepage influence or with only a temporary seepage influence 1) Moderately dry lithic habitats or habitats with shallow soils 2) Mesic habitats with shallow to deep soils 3) Hygric habitats with deep soils and a temporary seepage influence ii) Forested units of hygric habitats with a permanent seepage influence 1) Seepage fast-flowing in stream-edge or spring-line habitats 2) Seepage slow-moving or stagnating in depressions or spring-line habitats iii) Non-forested semi-terrestrial moor habitats As orders and alliances include units of lower rank with strong environmental and floristic similarities to those found in other biogeoclimatic zones and subzones and elsewhere, a new dimension is added to the organization of ecosystematic units. The Subalpine Mountain Hemlock Zone coincides with the main distributional area of Tsuga mertensiana -- an area with a cool, snowy forest climate (Dfc after Koppen), podzolization and gleization as the dominant soil-forming processes, and with the development of Humic and Humus Podzol soils with thick, acid accumulations of mycelial ecto-humus on mesic zonal habitats. Discontinuity in the forest cover coinciding with an increasing duration of snow provides a physiognomic, floristic and climatic basis for the recognition of the Parkland and Forest Subzones. Vegetation and soil patterns and relationships in the Parkland Subzone are evidently most influenced by snow duration, soil moisture regime, topography and microclimate, whereas soil moisture regime, land type and topography are important influences in the Forest Subzone. The interplay of compensatory influences may promote the development of similar floristic patterns on different topographic forms on an intra- and interzonal scale. The environmentally integrating influence of snow depth and duration in the Parkland Subzone results in sharp floristic and microclimatic patterns. Vegetation may have a strong autogenic influence on microenvironmental dynamics by hastening snow melt and extending length of the growing season over short distances. Dynamics within the zone favoring successional trends are proceeding at a very slow rate. Climatic changes shortening the duration of snow rather than cumulative autogenic influences would probably contribute most to vegetation changes at high elevations in the subalpine zone. / Science, Faculty of / Botany, Department of / Graduate

This thesis is concerned with plant associations within the Subalpine Mountain Hemlock Zone as indicators of recreational land use capability. With the field recognition of approximately twenty plants (trees, tall shrubs, low shrubs, and ground plants) all the plant associations within this zone can be identified. Knowing the biogeoclimatic characteristics of the plant associations and the limitations of land for recreation, land use decisions concerning summer recreation can be made. The objectives are to develop criteria for rating the limitation of land for selected recreational activities; to summarize information about the plant associations and biogeoclimatic conditions found within the Subalpine Mountain Hemlock Zone of southwestern British Columbia for planning purposes; to assign capability ratings to land based on the biogeoclimatic characteristics of the plant associations and on the criteria for rating the limitation of land for recreational activities; and to illustrate how the capability ratings of plant associations for recreation can be used in recreation planning. This study is a response to the need for a simple, rapid, accurate, inexpensive, site specific approach to land use planning based on readily recognizable indicators. By identifying and mapping plant associations, a recreational land use capability distribution is made apparent. With such detailed site specificity, planners and natural resource managers can make rational decisions about land use based on the biogeoclimatic characteristics of plant associations and on the limitations of land for recreational activities. It is suggested that the land use planning approach presented in this thesis can be extended not only to other biogeoclimatic zones besides the Subalpine Mountain Hemlock Zone but also to other activities besides recreation. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

Accelerating biodiversity change is a defining characteristic of the Anthropocene, and evidence accumulated from almost 30 years of research is often invoked to suggest that these changes will have catastrophic effects on ecosystems and the services they provide to humanity. In this thesis I use theory, empirical analysis and their combination to address key remaining issues surrounding the relationship between biodiversity, ecosystem function and ecosystem services. First, while the asymptotic relationship between biodiversity and ecosystem function is substantiated from experiments that randomly assemble plant communities, the response of ecosystems to directional biodiversity loss is highly variable. In the first two chapters I investigate how species level attributes (vulnerabilities, functional contributions) and community dynamics (compensation, non-random extinction) scale to affect individual and multiple ecosystem functions simultaneously. Second, a narrow set of plant-based ecosystem functions have come to dominate the field, and with few exceptions, linking these to the ecosystem services that directly affect human well-being has been challenging. Inland fisheries provide millions of people with their primary source of essential nutrients (e.g., protein, omega-3 fatty acids, iron, zinc), but are threatened by hydropower development, overfishing and climate change. The last three chapters explore how fish biodiversity both responds to these threats, influences fisheries production and affects nutritional security in the Amazon, Earth’s largest and most productive river basin. Additionally, I evaluate how alternative strategies to ameliorate fisheries declines that hinge on substituting wild fish with farmed animals can meet nutritional goals. By combining theoretical and empirical approaches and integrating concepts from ecology, fisheries, nutrition and economics, this body of work illuminates key drivers surrounding the variation observed in how ecosystems respond to biodiversity change, and the implications of these changes for the sustainability of aquatic food systems. Compensation can maintain biomass production, but incur strong changes in community composition. Differences in species vulnerabilities as well as in their functional contributions can predict the degree to which these compositional changes affect ecosystem functions. When considering critical ecosystems services, such as the contribution of inland fisheries to human nutrition, declining biodiversity always comes at the cost of increasing nutritional risk. This risk cannot be minimized by substituting wild fish with poultry or aquaculture species. Thus, investment in managing biomass production together with biodiversity, such as through protecting key habitats, maintaining riverine connectivity and enacting temporary closures, will maximize the long-term contribution of wild fisheries to human nutrition. Additionally, diversifying farmed animal production by interspersing high valued species with highly nutritious species can deliver both economic and food security benefits. More broadly, by illuminating how biodiversity contributes to the sustainability of food systems, this thesis provides new basic and applied dimensions to the field of biodiversity and ecosystem function. Further, the findings presented here demonstrate how an interdisciplinary approach can shed light on the intertwined relationships between biodiversity, ecological dynamics and Earth’s ongoing sustainability.

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