Mapping Cladophora and Other Submerged Aquatic Vegetation in the Great Lakes Using Satellite Imagery
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Michigan Technological University Digital Commons @ Michigan Tech Michigan Tech Research Institute Publications Michigan Tech Research Institute 5-2012 Mapping Cladophora and other submerged aquatic vegetation in the Great Lakes using satellite imagery. Colin Brooks Michigan Technological University Michael Sayers Michigan Technological University Robert Shuchman Michigan Technological University M. T. Auer Michigan Technological University Guy Meadows Michigan Technological University See next page for additional authors Follow this and additional works at: https://digitalcommons.mtu.edu/mtri_p Part of the Life Sciences Commons, and the Physical Sciences and Mathematics Commons Recommended Citation Brooks, C., Sayers, M., Shuchman, R., Auer, M. T., Meadows, G., & Jessee, N. (2012). Mapping Cladophora and other submerged aquatic vegetation in the Great Lakes using satellite imagery.. IAGLR 55th Annual Conference on Great Lakes Research. Retrieved from: https://digitalcommons.mtu.edu/mtri_p/112 Follow this and additional works at: https://digitalcommons.mtu.edu/mtri_p Part of the Life Sciences Commons, and the Physical Sciences and Mathematics Commons Authors Colin Brooks, Michael Sayers, Robert Shuchman, M. T. Auer, Guy Meadows, and Nathaniel Jessee This conference paper/presentation is available at Digital Commons @ Michigan Tech: https://digitalcommons.mtu.edu/mtri_p/112 55th Annual Conference of the International Association for Great Lakes Research FromFrom GreatGreat LakesLakes flowflow MightyMighty RiversRivers ABSTRACT BOOK IAGLR CORNWALL ONTARIO CANADA May 13-17, 2012 55th Annual Conference Internaonal Associaon for Great Lakes Research Conference (IAGLR) From Great Lakes Flow Mighty Rivers IAGLR May 13‐17, 2012 NavCentre, Cornwall, ONTARIO CANADA PUBLISHED BY Internaonal Associaon for Great Lakes Research Office 4840 South State Rd., Ann Arbor, Michigan 48108 www.iaglr.org COPYRIGHT 2012 IAGLR 2012 From Great Lakes Flow Mighty Rivers Conference Commiee Conference Co‐Chairs Dr. Jeff Ridal, Execuve Director St. Lawrence River Instute of Environmental Sciences Commi Dr. Peter Hodson, Queen’s University Dr. Linda Campbell, Queen’s University and St. Mary’s University ee and Program Chairs IAGLR Dr. Jeff Ridal, Execuve Director St. Lawrence River Instute of Environmental Sciences Dr. Jérôme Marty, Research Scienst Board St. Lawrence River Instute of Environmental Sciences of Conference Coordinator Local Organizing Coordinator Directors Mary Ginnebaugh Chrisna Collard IAGLR Business Manager Wendy L. Foster IAGLR Officers and Board Members: Officers Robert J. Letcher, President Our sincere appreciaon for their James R. Bence, Vice President contribuon Robert Heath, Past President Paula McIntyre, (Lorac Design LLP) Thomas M. Holsen, Treasurer Michael Twiss Amanda E. Poste, Acng Secretary Session Chairs Our Volunteers Board Members IAGLR Board of Directors Linda Mortsch Prosper Zigah, Student Member Conference Commiee Katherine Hargan, Student Member Sco Higgins Stephen R. Hensler Peter J. Dillon IAGLR 2012 From Great Lakes Flow Mighty Rivers 4 IAGLR 2012- Book of abstracts ABMA, R.A. and HAFFNER, G.D., Great Lakes Institute for Environmental Research, 401 Sunset Ave., Windsor, ON, N9B 3P4. Mercury Bioaccumulation in Lake Trout Reflects Non-Steady State Dynamics. Mercury toxicity has been a relevant, global issue since it was discovered to be a severe neurotoxin in 1958. Mercury levels in the Great Lakes region have been monitored since the 1970s after the first signing of the Great Lakes Water Quality Agreement. Since then, bioenergetics and kinetics models have been proposed as means of predicting mercury body burden in fish. Although these models are accurate for some species and sites, they are less predictive when applied to others. My study investigated an assumption associated with current models: that all parameters remain constant over time. The study looked at lake trout, a predatory species used for contaminant biomonitoring since the late 1970s. 150 lake trout were collected from 4 sites across Lake Huron, then were processed and analyzed for whole-body mercury contamination. Individuals were aged using otoliths and separated into age classes. Cohort analysis revealed a nonlinear increase of mercury body burden with increasing age, indicating that lake trout do not reach steady state mercury accumulation at any time between the ages of 0- 11. This means that one or more parameters of the model continue to change over time. These data emphasize the necessity of considering non-steady state accumulation dynamics for future bioenergetics and kinetics modeling of mercury. Keywords: Trout, Bioaccumulation, Mercury. ACKERMAN, J.D.1, BOUFFARD, D.1, BOEGMAN, L.2, and YERUBANDI, R.R.3, 1Integrative Biology, University of Guelph, Guelph, ON, N1G 2W1; 2Civil Engineering, Queen's University, Kingston, ON, K7L 3N6; 3Environment Canada, National Water Research Institute, Burlington, ON, L7R 4A6. Impact of Physical Processes on the Oxygen Depletion in Central Lake Erie. Hypoxia in the hypolimnion of Lake Erie has been examined by assessing (i) the spatial and temporal extent of the hypoxia and (ii) linking the rate of oxygen (DO) depletion to the hypolimnion thickness. The former has shown that hypoxia typically occurs between July and October in the central basin and can extend over 104 km2, whereas the latter has shown that a thin hypolimnion is needed to sustain low DO. However, assessing the processes driving inter- annual variability in oxygen and the small-scale temporal and spatial patchiness in DO depletion (-2 to +1 mg/L/d) remain unknown. The goal of the present study is to focus on the short-term variability in DO depletion and its link to the rate of vertical mixing. The use of a vertical oxygen budget enabled us to quantify how much of the DO variability is controlled by physical processes, relative to biological processes and the sediment oxygen demand (SOD). The data are the summers of 2008 and 2009 in central Lake Erie involving 13 moorings with high-frequency temperature loggers, acoustic Doppler current profilers, dissolved oxygen loggers, chlorophyll and turbidity loggers and temperature microstructure profiles. These high-temporal resolution field data allowed us to investigate the dynamics of the oxygen depletion. Keywords: Lake Erie, Hydrodynamics, Oxygen. 5 IAGLR 2012- Book of abstracts AHMED, S. and TROY, C.D., Purdue University, 550 Stadium Mall Drive, West Lafayette, IN, 47907-2051. Spatial Structure of Poincare Waves in Lake Michigan. Near-inertial (Poincare) internal waves are the dominant basin-scale baroclinic response to wind forcing in the Great Lakes during the stratified period. The spatial structure of these ubiquitous waves is not well-understood for Lake Michigan, which has important implications for the spatial distributions of vertical mixing, lateral dispersion, and near-bottom turbulence. To investigate the spatial structure of the dominant Poincare modes, three-dimensional numerical simulations are carried out with the unstructured numerical model SUNTANS. Both idealized wind forcing - spatially uniform wind impulses lasting for half the inertial period - as well as observed wind fields are used to drive the model. While the nearly-identical periods of the dominant modes excited make their separation difficult, an attempt is made to reconcile the observed structure with known modal structure in large lakes (e.g. Schwab 1977). In addition to basic induced currents and thermocline displacements, the observed mode structure is used to identify elevated shear and cross-thermocline mixing potential hotspots. The effect of seasonal changes in stratification on Poincare modes and the corresponding shear and cross-thermocline mixing are also examined. Keywords: Hydrodynamic model, Internal waves, Waves, Poincare, Lake Michigan, Basin scale. ALBEN, K.T.1, SOBIECHOWSKA, M.2, BRIDOUX, M.3, and FUENTETAJA, A.P.4, 1New York State Dept Health, Empire State Plaza, Albany, NY, 12201-0509; 2Polish Academy of Sciences, Institute of Oceanography, Marine Chemistry and Biochemistry, Sopot, 81-712, Poland; 3University of Washington, School of Oceanography, Seattle, WA, 98195-5351; 4Buffalo State College, Biology Dept., Buffalo, NY, 14222. Use of Algal Pigments to Trace Food-Web Relationships between Invertebrates and Fish in the Great Lakes. Pigments representing different classes of algae were determined in diverse benthic invertebrates and species of fish, primarily from the eastern basin of Lake Erie (2003 to 2005), with some from Lakes Ontario (LO) and Superior (LS). Benthic invertebrates were distinguished by pigments from their diet, with bioaccumulation factors ranging from 4 (dreissenids and chironomids, LS diporeia) to 25 (oligochaetes; LS mysis; LO dreissenids). Specific tissues of fish helped differentiate recent ingestion (digestive tract of small fish; stomach and intestinal contents of large fish) from cumulative diet (liver; muscle; skin; eyes; brain; gonads). Chlorophyte biomarkers were common to digestive tracts of nearshore fish (yellow, white and trout perch, rock bass, black crappie, round goby; only sheepshead negative). Astaxanthin, a crustacean biomarker, was more widely dispersed (nearshore trout perch, rock bass; offshore pelagic rainbow smelt, emerald shiner; offshore benthic L trout). Biomarkers for diatoms, cryptophytes and cyanobacteria were found in digestive tracts and livers of many fish. Levels of bioaccumulation ranged from low (< 10-fold: rainbow smelt, emerald shiner,