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Cattail Invasion of Sedge/Grass Meadows in Lake Ontario: Photointerpretation Analysis of Sixteen Wetlands over Five Decades
, 2008
"... ABSTRACT. Photointerpretation studies were conducted to evaluate vegetation changes in wetlands of Lake Ontario and the upper St. Lawrence River associated with regulation of water levels since about 1960. The studies used photographs from 16 sites (four each from drowned river mouth, barrier beach, ..."
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ABSTRACT. Photointerpretation studies were conducted to evaluate vegetation changes in wetlands of Lake Ontario and the upper St. Lawrence River associated with regulation of water levels since about 1960. The studies used photographs from 16 sites (four each from drowned river mouth, barrier beach, open embayment, and protected embayment wetlands) and spanned a period from the 1950s to 2001 at roughly decadal intervals. Meadow marsh was the most prominent vegetation type in most wetlands in the late 1950s when water levels had declined following high lake levels in the early 1950s. Meadow
PROGRAM IN BIOLOGY
, 2011
"... This Thesis is brought to you for free and open access by the Theses and Dissertations at Loyola eCommons. It has been accepted for inclusion in Master's Theses by an authorized administrator of Loyola eCommons. For more information, please contact ecommons@luc.edu. ..."
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This Thesis is brought to you for free and open access by the Theses and Dissertations at Loyola eCommons. It has been accepted for inclusion in Master's Theses by an authorized administrator of Loyola eCommons. For more information, please contact ecommons@luc.edu.
2Department of Natural Resources
"... ABSTRACT. Plant taxa identified in 90 U.S. Great Lakes coastal emergent wetlands were evaluated as indicators of physical environment. Canonical correspondence analysis using the 40 most common taxa showed that water depth and tussock height explained the greatest amount of species-environment inter ..."
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ABSTRACT. Plant taxa identified in 90 U.S. Great Lakes coastal emergent wetlands were evaluated as indicators of physical environment. Canonical correspondence analysis using the 40 most common taxa showed that water depth and tussock height explained the greatest amount of species-environment interac-tion among ten environmental factors measured as continuous variables (water depth, tussock height, lati-tude, longitude, and six ground cover categories). Indicator species analysis was used to identify species-environment interactions with categorical variables of soil type (sand, silt, clay, organic) and hydrogeomorphic type (Open-Coast Wetlands, River-Influenced Wetlands, Protected Wetlands). Of the 169 taxa that occurred in a minimum of four study sites and ten plots, 48 were hydrogeomorphic indicators and 90 were soil indicators. Most indicators of Protected Wetlands were bog and fen species which were also organic soil indicators. Protected Wetlands had significantly greater average coefficient of conservatism (C) values than did Open-Coast Wetlands and River-Influenced Wetlands, but average C values did not differ significantly by soil type. Open-Coast and River-Influenced hydrogeomorphic types tended to have sand or silt soils. Clay soils were found primarily in areas with Quaternary glaciolacustrine deposits or clay-rich tills. A fuller understanding of how the physical environment influences plant species distribution will improve our ability to detect the response of wetland vegetation to anthropogenic activities.
Geographic, anthropogenic, and habitat influences on Great Lakes coastal wetland fish assemblages
"... Abstract: We analyzed data from coastal wetlands across the Laurentian Great Lakes to identify fish assemblage patterns and relationships to habitat, watershed condition, and regional setting. Nonmetric multidimensional scaling (NMDS) ordi-nation of electrofishing catch-per-effort data revealed an o ..."
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Abstract: We analyzed data from coastal wetlands across the Laurentian Great Lakes to identify fish assemblage patterns and relationships to habitat, watershed condition, and regional setting. Nonmetric multidimensional scaling (NMDS) ordi-nation of electrofishing catch-per-effort data revealed an overriding geographic and anthropogenic stressor gradient that ap-peared to structure fish composition via impacts on water clarity and vegetation structure. Wetlands in Lakes Erie and Michigan with agricultural watersheds, turbid water, little submerged vegetation, and a preponderance of generalist, toler-ant fishes occupied one end of this gradient, while wetlands in Lake Superior with largely natural watersheds, clear water, abundant submerged vegetation, and diverse fishes occupied the other. Fish composition was also related to wetland mor-phology, hydrology, exposure, and substrate, but this was only evident within low-disturbance wetlands. Anthropogenic stress appears to homogenize fish composition among wetlands and mask other fish–habitat associations. Because land use is strongly spatially patterned across the Great Lakes and aquatic vegetation is a key habitat element that responds to both biogeography and disturbance, it is difficult to disentangle natural from anthropogenic drivers of coastal wetland fish com-position. Résume ́ : Nous analysons des données provenant de terres humides riveraines réparties sur l’ensemble des Grands Lacs laurentiens afin d’identifier les patrons d’associations de poissons et leurs relations avec les habitats, les conditions du bas-sin versant et l’environnement régional. Une ordination de cadrage non métrique multidimensionnel (NMDS) de données
Article Development of a Bi-National Great Lakes Coastal Wetland and Land Use Map Using Three-Season PALSAR and Landsat Imagery
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Predicting Wetland Plant Community Responses to Proposed Water-level-regulation Plans for Lake Ontario: GIS-based Modeling
, 2007
"... Human activities have modified natural water-level fluctuations in the Great Lakes through exca-vation of connecting channels and regulation at the outlets of Lakes Superior and Ontario. Regulation ..."
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Human activities have modified natural water-level fluctuations in the Great Lakes through exca-vation of connecting channels and regulation at the outlets of Lakes Superior and Ontario. Regulation
Linda Caruso
"... This report is available for viewing, printing or downloading at freshwaterestuary.uwex.edu. Cover photos by Patrick Robinson.-i-Acknowledgements We extend our gratitude and appreciation to the following individuals who offered their time and expertise to assist with facilitating the community worki ..."
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This report is available for viewing, printing or downloading at freshwaterestuary.uwex.edu. Cover photos by Patrick Robinson.-i-Acknowledgements We extend our gratitude and appreciation to the following individuals who offered their time and expertise to assist with facilitating the community working sessions for this project:
J. Great Lakes Res. 33 (Special Issue 3):67–85 Internat. Assoc. Great Lakes Res., 2007 Water Quality in Great Lakes Coastal Wetlands: Basin-wide Patterns and Responses to an Anthropogenic Disturbance Gradient
"... ABSTRACT. We present water quality data from 58 coastal wetlands, sampled as part of a larger effort investigating effects of nutrient enrichment and habitat disruption in the Laurentian Great Lakes. Our sampling design selected sites from across a gradient of agricultural intensity within combinati ..."
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ABSTRACT. We present water quality data from 58 coastal wetlands, sampled as part of a larger effort investigating effects of nutrient enrichment and habitat disruption in the Laurentian Great Lakes. Our sampling design selected sites from across a gradient of agricultural intensity within combinations of biogeographic ecoprovince and wetland hydromorphic type and captured a large range in water quality. Levels of total nutrients (N and P), and various measures of particulate concentration, water clarity, and ionic strength were strongly associated with agricultural intensity in the watershed, and could be effec-tively aggregated into an overall principal component-based water quality descriptor. Lake Erie wetlands had the highest nutrient levels and lowest water clarity, while wetlands in Lakes Superior and Huron had the lowest nutrient levels and clearest water. Lake Ontario wetlands had clearer water than would be expected from their nutrient levels and position on the agricultural intensity gradient. Dissolved oxygen, silica, pH, and dissolved organic carbon (DOC) were independent of agricultural intensity but DOC was responsible for low water clarity in some Lake Superior wetlands. Simple classification by hydromorphic type (riverine or protected) did not explain water quality differences among wetlands exposed to similar agricultural intensity levels, so finer hydrologic classification may be desirable. Results are used as a basis for discussing research and information needs underlying development of water quality criteria and monitoring programs for coastal wetlands of the Great Lakes.
