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Electronic Theses and Dissertations

2003

Ecology.

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The Relationship Between Anthropogenic Disturbance And The Distribution Of A Nonindigenous Species, Echinogammarus Ischnus Stebbing, 1898 (Amphipoda: Gammaridae), At Great Lakes Coastal Margins, Misun Kang Jan 2003

The Relationship Between Anthropogenic Disturbance And The Distribution Of A Nonindigenous Species, Echinogammarus Ischnus Stebbing, 1898 (Amphipoda: Gammaridae), At Great Lakes Coastal Margins, Misun Kang

Electronic Theses and Dissertations

Invasive species are becoming increasingly common components of Great Lakes zoobenthic communities. Elton (1958) proposed that biotic resistance against exotic species establishment is greater in intact communities than in those disturbed by human activities. However, Baltz and Moyle (1993) suggested that if abiotic conditions are appropriate, invasion is likely, regardless of the biota already present. I tested these hypotheses by investigating the distribution of Echinogammarus ischnus Stebbing, 1898, an exotic amphipod, at U.S. Great Lakes coastal margin sites influenced by varying degrees of anthropogenic stress. Thirty-nine sites supporting Gammarus fasciatus Say, 1818, a common amphipod with habitat preferences similar to …


Propagule Pressure: A Null Model For Biological Invasions., Robert I. Colautti Jan 2003

Propagule Pressure: A Null Model For Biological Invasions., Robert I. Colautti

Electronic Theses and Dissertations

I begin with a review of recent attempts to identify characteristics of species 'invasiveness' (i.e., the ability to invade) and habitat 'invasibility' (i.e., the susceptibility to invasion), and find little support for an emerging consensus on species- or habitat-specific characteristics. Moreover, I find that few studies consider hypotheses based on the concept of 'propagule pressure' (i.e., introduction effort), despite its potential as a confounding factor. Another barrier to generalizations may be the divergent use of operationally important terms like 'invasive', 'naturalized', or 'nuisance'. I therefore introduce a framework that conceptualizes biological invasions as a series of obligatory stages. This stage-based …


Factors Regulating Biomass And Contaminant Uptake By Round Gobies (Neogobius Melanostomus) In Western Lake Erie., Victoria Ann. Lee Jan 2003

Factors Regulating Biomass And Contaminant Uptake By Round Gobies (Neogobius Melanostomus) In Western Lake Erie., Victoria Ann. Lee

Electronic Theses and Dissertations

Round gobies, an invasive fish from the Ponto-Caspian region of Eastern Europe arrived in the western basin of Lake Erie in 1993. A bioenergetics model was developed for round gobies to quantify the flow of energy and contaminants from the benthos to pelagic fishes. Weight and temperature dependent coefficients for metabolism and consumption were derived. Food consumption increased with temperature up to 26°C before sharply decreasing and decreased with increasing fish weight. Oxygen consumption was inversely related to body mass and increased exponentially with temperature. Additional parameters were obtained from the literature to describe specific dynamic action, egestion and excretion. …


Zoobenthic Succession In Constructed Wetlands Of The Fort Mcmurray Oil Sands Region: Developing A Measure Of Zoobenthic Recovery (Alberta)., Christel Lynn. Leonhardt Jan 2003

Zoobenthic Succession In Constructed Wetlands Of The Fort Mcmurray Oil Sands Region: Developing A Measure Of Zoobenthic Recovery (Alberta)., Christel Lynn. Leonhardt

Electronic Theses and Dissertations

This study investigated the effect of oil sands process material (OSPM) on the zoobenthic community of constructed wetlands in the Fort McMurray oil sands region. The unique characteristics of OSPM-affected wetlands may modify the successional trajectory of invertebrate communities compared to that of high or low-conductivity reference wetlands. The zoobenthic community of 31 wetlands, aged 0 to 30 years, was simultaneously sampled, allowing inference into the chronological sequence of change that results with wetland succession. Wetlands were categorised a priori into one of three classes: low conductivity (<700 muS/cm) or high conductivity (700--2,500 muS/cm) reference wetlands or OSPM-affected wetlands (700--4,000 muS/cm) containing tailings and/or water from bitumen extraction. Invertebrate communities in each wetland were assessed using core, artificial substrate, and sweep net sampling methods. Principal components analysis and discriminant function analysis were used to classify each OSPM-affected wetland as being "equivalent to young" or "equivalent to mature" reference wetlands. Restoration of mined areas to pre-mining conditions of diversity and abundance of habitat types, using wetlands as a component of a reclamation strategy, is a viable option. (Abstract shortened by UMI.)Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2003 .L46. Source: Masters Abstracts International, Volume: 42-02, page: 0520. Adviser: J. H. Ciborowski. Thesis (M.Sc.)--University of Windsor (Canada), 2003.


Primary Production And Phytoplankton Dynamics In Western Lake Erie., Mark Alan John. Fitzpatrick Jan 2003

Primary Production And Phytoplankton Dynamics In Western Lake Erie., Mark Alan John. Fitzpatrick

Electronic Theses and Dissertations

Primary production studies have had a profound impact on the management of the Great Lakes, culminating with the Great Lakes Water Quality Agreement of 1972 between Canada and the United States. The current study examined primary production and phytoplankton dynamics in western Lake Erie with application to water quality and fisheries management practices. Annual primary production, estimated using a 14carbon tracer and both in situ and constant light incubations, ranged from 320--370 g C m-2 y-1 during the study period and was similar to the 340 g C m-2 y -1 reported in the basin for 1970. Phytoplankton standing crop, …


Effects Of Land-Use Patterns And Land Ownership On Biodiversity In The Natural Areas Of The Niagara Escarpment World Biosphere Reserve (Ontario)., Rosamonde Ellen. Page Jan 2003

Effects Of Land-Use Patterns And Land Ownership On Biodiversity In The Natural Areas Of The Niagara Escarpment World Biosphere Reserve (Ontario)., Rosamonde Ellen. Page

Electronic Theses and Dissertations

Existing under the protection of provincial legislation, the natural areas and biodiversity of the Niagara Escarpment World Biosphere Reserve have been particularly well-studied. I mapped land ownership and land-use patterns in the land matrix surrounding each of the 98 designated natural areas of the Reserve area, and then analysed their effects on estimates of biodiversity. Increasing percentages of recreational land-use surrounding a natural area were associated with degradative effects on rare plant species, as well as species with endangered or threatened status. Numbers of provincially rare plant species and endangered or threatened species were positively related to increasing amounts of …