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ENV 259

Lecture 6 Lake Erie & the Erie Islands 11/01/08. ENV 259. Great Lakes. Great Lakes. Lake Michigan Lake Huron Lake Erie* Lake Ontario Lake Superior. Lake Erie. Human Utility 100 million tons of cargo 2.7 billion of the 100 billion gallons water/Day for urban/industrial

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ENV 259

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  1. Lecture 6 Lake Erie & the Erie Islands 11/01/08 ENV 259

  2. Great Lakes

  3. Great Lakes • Lake Michigan • Lake Huron • Lake Erie* • Lake Ontario • Lake Superior

  4. Lake Erie • Human Utility • 100 million tons of cargo • 2.7 billion of the 100 billion gallons water/Day for urban/industrial • Approx. 50 million Lbs. fish caught/ Annually by US&CA • Human Impact • Polluted effluent • Agric.,urban, & Industrial run-off • Low volume = poor assimilation (dilution) • Ohio controlls 3,500 Miles2 (largest US landowner.)

  5. Lake Erie

  6. Long, narrow 240 miles x 57 miles Like a river connecting Lake Huron to Ontario Shape of Lake Erie

  7. 3 Different Basins

  8. Lake Erie’s 3 Basins • Depth difference due to: • Differences in bedrock & glacial impact! • Harder bedrock, shallower areas • Eastern Basin • Soft Devonian, Mississipianshales • Central Basin • Still shales, but wider basin resulted in less glacial impact • Western Basin • Silurian & Devonian limestone & dolomite

  9. Lake Erie formed by…

  10. Water Quality & Flow • #1 water source for Lake Erie (over 90%) • Detroit River (drains Lake St. Clair & upper lakes) • 219,000 cubic feet/second • Strong flow results in currents in western lake (strong winds also influence surface currents) • #2 source of water • Maumee River • 4,700 cubic feet/second • Carries 37% of sediment loading

  11. Water Quality & Flow • Water temperature • Approx. 32F (winter) • to 75F (summer) • Ice • Up to 2ft thick on 100% of lake during severe winters • Commercial navigation ends from December through March • Deeper areas of lake have temperature gradations • Dissolved O2 • Varies with temperature, time of day, season – cooler means more oxygen

  12. Pollution, Invasive species, Erosion

  13. Pollution Effects • Nutrient loading • Pesticides • Agricultural fertilizers • Industrial heavy metals • Algae growth • Results in eutrophication (algae deplete O2 supply) • Impacts on fauna • Pollution tolerant species can survive • Lake flow & recharge rate…not enough to offset pollution • Even though 40% of Lake flows to Niagara Falls/year • Takes 2.5 years for to flush – drop of water travel time from west to east

  14. Zebra Mussels washed ashore

  15. Shore erosion & storm impact • High water of 1970’s = high erosion levels • Resulted in relocation 60 ft. inland of Coast Guard lighthouse on S. of S.Bass Island (due to erosion) • Wind influences water current due to shallowness

  16. Lake Erie Flora & Fauna

  17. Animal & Plant life • Plankton…plentiful in Lake • Phytoplankton (diatoms, blue-green algae) phyto = plant • Zooplankton (micro. Crustaceans, rotifers, protozoans) zoo = animals • “bottom” of food chain

  18. Animal & Plant life • Invertebrates • Mostly pollution tolerant species (midge larvae, fingernail clams, sludge worms, snails) • Signs of improvement (mayfly nymphs, larger clams, caddisfly larvae)

  19. Animal & Plant life • Fish • Historically important fishery due to temperature & higher nutrients • Spawning/nursery grounds restock lake and maintain populations • Perch, Smallmouth & White Bass, Channel catfish, and others now

  20. Fishery Deterioration • Due to • Watershed erosion & siltation , dam construction, dikes in wetlands • Reduced dissolved O2 due to pollution • Competition from invasive species • Increased/more efficient fishing techniques

  21. Animal Life - Species • Amphibians/Reptiles • Mudpuppy, frogs, salamanders, newts, toads, • Lake Erie water snake • Waterfowl/Birds • Important migratory flyway! • Herons, gulls, egrets, cormorants • Mammals • Very scarce on Erie Islands • Norway Rat, Black & gray squirrels, cottontail rabbits

  22. Plant Life • More than 850 species of vascular plants • Vascular plants: flowering plants, ferns, pines, decidous trees • Common N.American spp. dominate • Some invasives & imports • Yellow water lilies • Orchards & vineyards

  23. Lake Erie Islands & Caves

  24. Island Climate • Unique microclimate • When compared with mainland Ohio: • Annual mean temp.range > than mainland • Daily min/max range < than mainland • Less precipitation • Longer frost-free season • South Bass Island (Put-in-Bay) = approx. 205 days/yr • Bucyrus (50 miles inland) = 154 days frost-free/yr • Colder in winter, warmer in summer • Drier year ‘round

  25. Lake Erie Islands • 12 Major Islands • Limited year round residents • Historically ag • Shallow soils and long frost free more ideal for fruit - grapes • Now primarily Tourist

  26. Erie Island Cliffs • Comprised of Limestone & dolomite • Cliffs created by: • Action of waves, particularly on W. side of islands • Freeze and thaw – frost wedging

  27. Lake Plains

  28. Lake Plains • Stretch from west to east along the lake shore • Home to about 3 million of Ohio’s 11 million people • 3 unique areas

  29. Great Black Swamp • 1,500 sq miles • Poor travel conditions so one of the last areas settled • Useless until drained • Very fertile ag soils

  30. Oak Openings • Sand layer sitting over clay • Clay and high water table cause poor drainage • Home to 6 well defined habitats

  31. Oak Openings • Dunes – Oaks, goldenrod, dry • Swamp Forest – between dunes, wet, pin oak, spicebush • Bogs – very wet, willow, buttonbush • Wet Prairies – very limited now • Abandoned Uplands – prairie species • Floodplain Valleys – Swan Creek and Ottawa River

  32. Lake Erie Marshes • Mostly along the western basin area • Once much more extensive then today • Protect inland from lake “surge” – wave action • Also protect from changing lake levels • Historic low in 1938 and high in 1973 • Driven by precipitation, draught, seiche

  33. Lake Erie Marshes • More diversity of plants and animals than any other area in State • Extremely valuable to economy, biodiversity, protection, birds, trapping, etc

  34. Field Trip • Rocky River Nature Center • 24000 Valley ParkwayRocky River ReservationNorth Olmsted • I-71 south to I-480 west, exit at Grayton Road, go north on Grayton (left?) to Puritas. Turn left on Puritas and go down hill. At bottom of hill turn left on Valley Parkway. Center will be a couple miles on your right.

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