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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

Channel geomorphic units as benthic macroinvertebrate habitat in small, high gradient streams on Vancouver Island, British Columbia

Halwas, Karen L. 05 1900 (has links)
Headwater streams typically have no fish, owing to steep gradients and impassible barriers; therefore, scientific research and protection measures have been focused on fish bearing streams. The Scientific Panel for Sustainable Forest Practices in Clayoquot Sound (CSP) developed a channel classification system which is pertinent to all streams, fishless and fish bearing alike, and upon which management prescriptions in Clayoquot Sound, Vancouver Island, British Columbia are based (CSP, 1995). The CSP classification delineates channels according to four physical criteria: bed material, gradient, entrenchment, and width. The current study was undertaken to determine the efficacy with which the CSP classification system delineates small, steep streams, on the basis of channel geomorphic units within them, and to examine the benthic macroinvertebrate habitat capability of these geomorphic units. Falls, bedrock cascades, boulder cascades, rapids, chutes, riffles, glides, and pools were described according to their bed slope and dominant channel-material type and organization. In addition, the area of each geomorphic unit was measured. Seventeen streams were grouped into four CSP channel classes which were compared with respect to the mean relative proportion of class area in geomorphic units. Stratified random benthic samples were extracted from geomorphic units in order to investigate and to compare their habitat capability. "Alluvial channels" in the study exhibited only weak, very infrequent fluvial transport; therefore, they were termed semi-alluvial. In general, high gradient geomorphic units (i.e. bedrock and boulder cascades) were dominant in steep, largely non-alluvial channels. Lower gradient units (i.e. riffles and rapids) were common in semi-alluvial streams with more mild slopes. Accordingly, channel classes with opposing bed material and gradient designations exhibited notable differences with respect to relative proportions of geomorphic units while width and entrenchment designations exerted little influence on channel organization. Ultimately, only two of the four CSP classification criteria effectively systematized channels on the basis of channel geomorphic units within them. Abundance of benthic macroinvertebrates was greatest in riffles (≈100 individuals per two minute kick sample), followed by rapids (≈80 individuals/sample), pools (≈70 individuals/sample), boulder cascades (≈60 individuals/sample), chutes (≈50 individuals/sample), and lowest in bedrock cascades (≈25 individuals/sample). In addition, abundance of invertebrates in channels with ephemeral flow regimes was considerably lower compared to channels with seasonal or perennial flow regimes. Ordination of macroinvertebrate taxa showed that community structure of bedrock cascades and chutes were similar but different from other habitats. Similarly, the benthic macroinvertebrate community structure of channels with ephemeral flow regimes was very distinct.
22

A community perspective : conflicting environmental interests and barriers to effective collaborative management in Clayoquot Sound

Henn, Rebecca 20 January 2010 (has links)
Our increased knowledge and awareness of the environment and the finite capacity of the world‘s resources has seen increased regional tensions and conflicts over natural resource development and land use planning. This study uses two separate approaches to investigation, incorporating case study method and grounded theory analysis. The region of Clayoquot Sound has a history of land use controversy from which to index the nature and complexity of conflicting interests. In conducting a conflict assessment and thematic frame analysis this study explores the nature of conflicting perceptual frames and arrives at an explanatory theory about how those frames contribute to conflict situations and present barriers to effective communication and participation in collaborative management efforts. The final discussion highlights ways in which approaches to dealing with value diversity can help build shared understandings and reduce biases and mistrust, which tend to exacerbate conflict, and improve capacity for action.
23

Channel geomorphic units as benthic macroinvertebrate habitat in small, high gradient streams on Vancouver Island, British Columbia

Halwas, Karen L. 05 1900 (has links)
Headwater streams typically have no fish, owing to steep gradients and impassible barriers; therefore, scientific research and protection measures have been focused on fish bearing streams. The Scientific Panel for Sustainable Forest Practices in Clayoquot Sound (CSP) developed a channel classification system which is pertinent to all streams, fishless and fish bearing alike, and upon which management prescriptions in Clayoquot Sound, Vancouver Island, British Columbia are based (CSP, 1995). The CSP classification delineates channels according to four physical criteria: bed material, gradient, entrenchment, and width. The current study was undertaken to determine the efficacy with which the CSP classification system delineates small, steep streams, on the basis of channel geomorphic units within them, and to examine the benthic macroinvertebrate habitat capability of these geomorphic units. Falls, bedrock cascades, boulder cascades, rapids, chutes, riffles, glides, and pools were described according to their bed slope and dominant channel-material type and organization. In addition, the area of each geomorphic unit was measured. Seventeen streams were grouped into four CSP channel classes which were compared with respect to the mean relative proportion of class area in geomorphic units. Stratified random benthic samples were extracted from geomorphic units in order to investigate and to compare their habitat capability. "Alluvial channels" in the study exhibited only weak, very infrequent fluvial transport; therefore, they were termed semi-alluvial. In general, high gradient geomorphic units (i.e. bedrock and boulder cascades) were dominant in steep, largely non-alluvial channels. Lower gradient units (i.e. riffles and rapids) were common in semi-alluvial streams with more mild slopes. Accordingly, channel classes with opposing bed material and gradient designations exhibited notable differences with respect to relative proportions of geomorphic units while width and entrenchment designations exerted little influence on channel organization. Ultimately, only two of the four CSP classification criteria effectively systematized channels on the basis of channel geomorphic units within them. Abundance of benthic macroinvertebrates was greatest in riffles (≈100 individuals per two minute kick sample), followed by rapids (≈80 individuals/sample), pools (≈70 individuals/sample), boulder cascades (≈60 individuals/sample), chutes (≈50 individuals/sample), and lowest in bedrock cascades (≈25 individuals/sample). In addition, abundance of invertebrates in channels with ephemeral flow regimes was considerably lower compared to channels with seasonal or perennial flow regimes. Ordination of macroinvertebrate taxa showed that community structure of bedrock cascades and chutes were similar but different from other habitats. Similarly, the benthic macroinvertebrate community structure of channels with ephemeral flow regimes was very distinct. / Arts, Faculty of / Geography, Department of / Graduate
24

The λ’aayaʕas Project: Revitalizing Traditional Nuu-chah-nulth Root Gardens

Pukonen, Jennifer C. 01 October 2008 (has links)
The Nuu-chah-nulth and other First Nations of coastal British Columbia used to maintain gardens of indigenous plants with edible roots on their estuarine tidal flats. Tasty and nutritious, these roots were carefully tended and nurtured to enhance their productivity and quality. Within the last century, the Nuu-chah-nulth diet has changed significantly, and these indigenous root vegetables are not as well known. This community-based action research project (The λ’aayaʕas Project) was suggested by members of the Nuu-chah-nulth communities of Clayoquot Sound, as a way of maintaining and strengthening traditional knowledge, cultural identity and ultimately, community health and well-being through renewal of awareness of these and other traditional foods. The λ’aayaʕas project engaged students and community members of all ages in a diverse range of activities aimed at revitalizing the knowledge, skills and cultural practices involved in caring for traditional root gardens. These activities have included: hosting community steam-pit cooking events; learning from knowledgeable community members; re-creating a root garden in the community of Ahousaht; and implementing and observing the results of traditional management techniques on a root garden plot at the Atleo River estuary. This thesis documents the development of this community action research project and examines the role of ecocultural restoration projects in providing opportunities to strengthen and facilitate the connection of youth to their land and culture through experiential learning. Discussions incorporate a summary of feedback and reflections on the project, and of the revitalization of traditional iv knowledge and practices locally, globally and in the future. In closing, I draw together thoughts and ideas from local community members and others who recognize and hope to revitalize the inextricable relationships between cultural and ecological health and diversity.
25

The foraging ecology of gray whales in Clayoquot Sound: interactions between predator and prey across a continuum of scales

Feyrer, Laura Joan 24 March 2010 (has links)
Understanding the ecology of an organism is fundamental for defining conservation and management priorities for wildlife and natural ecosystems. The most basic ecological framework identifies the key components of an organism's habitat, and the scale for measuring the quality of those features. How these core needs are expressed and vary in the surrounding ecosystem changes over time and space. In marine systems, the physical environment has few strict boundaries, and variations regularly occur on a scale from days to decades. The dynamic and patchy nature of marine habitat makes defining the ecological roles of an animal difficult, even where baseline data exists. In this study I analyze long term field records on the ecological interactions between foraging gray whales (Eschrichtius robustus), and their mysid prey (Family mysidae) in Clayoquot Sound, B.C. By looking at spatial and temporal shifts at both trophic levels, I measure foraging responses and requirements, and assess prey resource availability and resiliency in the marine environment at a series of scales. Appreciation for bottom-up and topdown trophic interactions provides the foundation for identifying natural variability in marine habitat, and a baseline for conservation measures that seek to use marine predators as a barometer of broader ecosystem health.
26

Marbled murrelet foraging ecology: spatial and temporal characteristics of habitat use in Clayoquot Sound, British Columbia.

Muirhead, Kyle Andrew 17 December 2010 (has links)
The marbled murrelet (Brachyramphus marmoratus) is listed as threatened in both Canada and the United States due to logging of old-growth forest stands, their primary nesting habitat. Existing research is primarily focused on this terrestrial aspect of the species’ ecology. Our understanding of their at-sea foraging ecology, however, is limited to broad-scale studies of population abundance and dynamics. In order to further understand the spatial and temporal variations of marbled murrelet at-sea foraging behaviour and habitat use, bi-weekly surveys of marbled murrelets were conducted in Clayoquot Sound, BC, between May 1 and September 1, 2007 and 2008. Data were first analysed using a Getis-Ord Gi* spatial analysis to identify high-use foraging areas. Total marbled murrelet presence was consistent between years, but spatial distribution varied significantly in both years. A subsequent analysis of oceanic environmental variables found that temperature, salinity and phytoplankton densities (measured as chl a) were spatially ubiquitous, with no significant variation in measures across the study area. Chl a levels showed significant temporal variation, though similar trends in marbled murrelet abundance over time in both seasons suggest that phytoplankton levels do not directly affect murrelet presence. Marbled murrelets were also observed foraging within several metres of gray whales (Eschrictius robustus) feeding on epibenthic zooplankton in 2006 and 2008, a previously undocumented relationship. Join count statistics identified significant clustering of murrelets up to 300m from 39 feeding gray whales in 2006, and no association with 5 gray whales in 2008, marking a foraging association conditional on the abundance of both gray whales and their prey, but potentially significant to marbled murrelet survival and fecundity.

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