To assess the relative contribution of phosphorus release from sediment in Cootes Paradise Marsh, I first examined spatial and temporal variability of laboratory-measured release rates from sediment samples collected from 12 sites within the wetland (Chapter 1 ). The microbial communities from these 12 sites were characterized on the basis of sole-carbon-source utilization using BIOLOG GN plates containing 95 substrates. Results from these experiments were entered into a principal component analysis and the release rates for all sites were regressed against corresponding PC 1 and PC2 scores (Chapter 2). Differences in microbial physiology as defined by PC 1 and PC2 scores accounted for 49% and 53%, respectively of the variation in phosphorus release rates. Using stepwise multiple regression, I concluded that the key determinants of laboratory-derived release rates from West Pond sediment (a highly eutrophic site within Cootes Paradise Marsh) are oxic state, ambient temperature and time of sediment collection (Chapter 3). Using this information I developed a multivariate model to predict release rates. This model, along with 2 alternative approaches, was used to estimate the extent of internal loading (kg d-1) in Cootes Paradise Marsh (Chapter 4). Method 1 was a highly controlled, static approach and resulted in an internal load of 11 .6 kg d-1, which was attributed to diffusion. The remaining two methods were more dynamic in nature as they took into account temporal variation, ambient temperature and the development of anoxia. Using Method 2, I estimated an internal load of 7.8 to 8.5 kgd-1, which was based on empirically-derived laboratory release rates. Method 3 consisted of the predictive model from which I estimated an internal load of 6.7 kgd-1• I attributed the release from the latter two methods to microbial mineralization processes. Based on this work and a previous estimate of internal loading in Cootes Paradise Marsh (Prescott & Tsanis 1997), I concluded that mineralization accounts for 22.3% of total phosphorus loading to the system, preceded only by urban runoff ( 41% ). / Thesis / Master of Science (MS)

Thesis (Ph.D.) -- McMaster University, 2001. / Includes bibliographical references. Also available via World Wide Web.

Wastewater effluent is a major source of aquatic pollution, discharging a continuous and complex mix of contaminants into the environment. The physiological impacts of exposure to individual contaminants are well characterized in fish, but less is known about the consequences of complex mixtures that typify wastewater effluent in the environment. This thesis explores the metabolic and respiratory effects of in situ wastewater exposure on bluegill sunfish (Lepomis macrochirus). By assessing multiple levels of biological organization, I provide evidence that wastewater exposure invoked a metabolic cost in bluegill, which was associated with physiological adjustments to enhance oxygen uptake, delivery, and utilization. These findings broaden our understanding of how fish tolerate life in effluent-dominated waters and support the emergence of metabolic and respiratory physiology as biomarkers in ecotoxicology. / Thesis / Master of Science (MSc)

<p>High density sampling (n=50) was conducted in Cootes Paradise, a shallow wetland on the western shoreline of Lake Ontario near the city of Hamilton. Cootes Paradise is an urban wetland that has been affected by pollutants and nutrients and invasive carp. Thecamoebian analyses paired with site specific environmental measurements (depth, sp. conductivity, temperature, DO and pH) and substrate characteristics (textural and organic content -LOI) show relationships (R² = 0.6) with depth (0-1m) and corresponding sp. conductivity (0.5 to 0.65 mS/cm) and temperature (26.5 to 30.5 °C). Q-mode cluster analysis recognized two biofacies. Biofacies 1 samples (n= 26) are found in the deeper areas (0.70 ± 0.27 m) and dominated by <em>C. tricuspis</em> 36 ± 8% (1 std), <em>L. vas</em> 18 ± 13% and <em>D. protaeiformis “claviformis”</em> 14 ± 6%. Mean water temperature is 28.0 ± 0.6 °C and conductivity at 0.56 ± 0.04 mS/cm. This assemblage has low species diversity (SDI=1.9 ± 0.3) which indicates a transitional environment. Biofacies 2 contains samples (n= 24) which are found in shallower areas (0.38 ± 0.15 m) and the assemblage is characterized by <em>C. constricta “aerophila”</em> 25 ± 8%, <em>C. tricuspis</em> 18 ± 5%, <em>Cyclopyxis sp.</em> 9 ± 6 % and <em>L. vas</em> 9 ± 4 %. The SDI for Biofacies 2 is 2.2 ± 0.2 and like Biofacies 1 shows a transitional environment. The average temperature is and 29.0 ± 1.0 °C with mean sp. conductivity also slightly higher than Biofacies 1 at 0.6 ± 0.04 mS/cm.</p> / Master of Science (MSc)

<p>Coates Paradise is a 250 ha coastal marsh, located at the western most point of Lake Ontario, adjoining Hamilton Harbour. Currently the marsh is severely degraded. Only 15% of the marsh remains vegetated, while the rest exists as an open water turbid bay. Stresses affecting the marsh include a very high carp population, excessive nutrient and sediment input, and water level regulation. Both Coates Paradise and Hamilton Harbour are the targets of an extensive remediation plan, known as the Hamilton Harbour Remedial Action Plan (HHRAP 1991 ).</p> <p>Coastal marshes are recognized for their importance as reproductive areas for the fish community. Considering the importance of marshes to fish, there is a surprising lack of information available. There have been very few comprehensive studies of whole fish communities and their use of marshes, and even fewer which address reproductive utilization. Herdendorf et. al. (1986) listed fish community structure and utilization of marshes for spawning, nursery and feeding areas as the top priorities of coastal wetland research.</p> <p>This study examines the fish community of Coates Paradise for the purpose of providing detailed information on the fish community in association with the HHRAP, as well as examining fish community use of the marsh with respect to reproductive utilization.</p> <p>The study included both temporal and spatial coverage of the marsh fish community. In an attempt to capture whole fish community data for Coates Paradise, fish community surveys were done monthly during the ice-free portion of the season. Surveys were initiated in the summer of 1994, followed by 3 full seasons between 1995 and 1997. Further to this, Coates Paradise was subdivided into 3 habitat types including off-shore, near-shore, and lower river. These habitats were further subdivided into sub-habitats, based on habitat variables that included wind fetch, nutrient enrichment, and degree of vegetation. A total of 8 sub-habitat types were included. Within each sub-habitat type four 50 m transects were located. The transects were surveyed by electrofishing.</p> <p>A total of 47,512 fish covering 47 species were captured in the study. Annual species diversity averaged 38 species, while monthly richness followed a seasonal trend with a maximum of 34 species occurring in July. Most species of fish were found to exist only in the near-shore habitat. Also the near-shore habitat had substantially more fish (Exposed sub-habitat -187 I transect) than the off-shore habitat (Bay sub-habitat -8 I transect).</p> <p>All species demonstrated migration into and out of the marsh in association with spawning periods and spawning habitat guilds. Most species of non YOY fish had highest densities at corresponding spawning times and in correlation to spawning habitat guilds. Habitat preferences of YOY species also generally reflected a species spawning habitat guild. Total non YOY populations were also generally at a peak during spawning periods. The non YOY of most species showed a distinct migration out of the marsh following spawning periods. Samples taken two months prior to a species spawning periods had almost no fish of the species occurring in the marsh, while samples taken two months following peak spawning periods resulted in almost no larger fish of a species being found in the marsh.</p> <p>The dominant fish species of the marsh was adult carp. In the electrofishing data, adult carp represented 90% of the biomass, but only 10% of the total catch. Only six other species had substantial adult population, while most other species are represent by less than 15 individuals in the data set. These six species included, brown bullhead, white sucker, gizzard shad, white perch, spottail shiner and pumpkinseed, and are reflective of the state of the harbour (the adult habitat).</p> <p>The most abundant species in the marsh include YOY of gizzard shad, white perch and spottail shiners, reflecting the marsh's role as reproductive habitat. Maximum numbers of fish occurred in late August, with as many as 800 fish being captured in a single transect. At this time the fish community consisted almost entirely of YOY fish.</p> / Master of Science (MSc)