1 / 36

Understanding Lake Erie and Solutions to Its History of Nutrient Enrichment and HABs

Understanding Lake Erie and Solutions to Its History of Nutrient Enrichment and HABs. Dr . Jeffrey M. Reutter Director, Ohio Sea Grant College Program. Lake Erie Stats. Drinking water for 11 million people Over 20 power plants Power production is greatest water use

cargan
Télécharger la présentation

Understanding Lake Erie and Solutions to Its History of Nutrient Enrichment and HABs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Understanding Lake Erie and Solutions to Its History ofNutrient Enrichment and HABs Dr. Jeffrey M. Reutter Director, Ohio Sea Grant College Program

  2. Lake Erie Stats Drinking water for 11 million people Over 20 power plants Power production is greatest water use 300 marinas in Ohio alone Walleye Capital of the World 40% of all Great Lakes charter boats Ohio’s charter boat industry is one of the largest in North America $1.5 billion sport fishery One of top 10 sport fishing locations in the world Most valuable freshwater commercial fishery in the world Coastal county tourism value is $11.6 billion & 117,000 jobs

  3. One of the Most Important Lakes in the World Dead lake image of 60s and 70s. Poster child for pollution problems in this country. But, most heavily utilized of any of the Great Lakes. Shared by 4 states and 2 countries. Best example of ecosystem recovery in world.

  4. Great Lakes Land Use Image: Ohio Sea Grant

  5. Photo: Ohio Sea Grant

  6. Photo: Ohio Sea Grant

  7. Major Land Uses in The Great Lakes

  8. Because of Land Use, Lake Erie Gets: More sediment More nutrients (fertilizers and sewage) More pesticides (The above 3 items are exacerbated by storms, which will be more frequent and severe due to climate change.) And Lake Erie is still biologically the most productive of the Great Lakes—And always will be!!

  9. 50:2 Rule (Not exact, but instructive) Lake Superior: 50% of the water and 2% of the fish Lake Erie: 2% of the water and 50% of the fish

  10. 80:10:10 Rule 80% of water from upper lakes 10% from Lake Erie tributaries 10% direct precipitation

  11. Nutrients: Problem or Benefit? On our lawns, they make our grass grow In water, they make algae and plants grow Lake Erie is most productive Great Lake because: shallowest, warmest, and most nutrients. But it is possible to have too much of a good thing. Too much algae, wrong kinds of algae

  12. Why does Lake Erie get most nutrients? The most agriculture in its basin Few forests Wetlands gone Large human population—water treatment, septic tanks, sewage treatment (or lack thereof)

  13. Historical Trends:The Lake Erie Ecosystem 1969—Cuyahoga River burns Getting worse annually to 1970 Stable 1970-75 Improving 1975-1995 1995+ Getting worse Photo: Ohio Sea Grant

  14. What brought about the rebirth? Phosphorus reductions from point sources (29,000 metric tons to 11,000);and agriculture helped!

  15. Why are we targeting phosphorus? Normally limiting nutrient in freshwater systems P reduction is best strategy ecologically and economically Reducing both P and N would help

  16. Phosphorus Sources • 1960s and 70s—primarily point sources (2/3) • Today loading is coming primarily from agriculture (2/3) but other sources include: • Sewage treatment plants and CSOs • Lawn fertilizer runoff • Water treatment plants • Septic tanks

  17. Impacts of Increased Phosphorus Concentrations • HABs—If P concentrations are high (regardless of the source, Ag, sewage, etc.) and water is warm, we will have a HAB (nitrogen concentration will likely determine which of the 6-7 species bloom) • Nuisance Algae Blooms • Cladophora—Whole lake problem. An attached form. • Dead Zone in Central Basin

  18. Blue-green Algae Bloom circa 1971, Lake Erie Photo: Forsythe and Reutter

  19. Microcystis, Stone Lab, 8/10/10 Photos: Jeff Reutter

  20. Microcystis in Lake Erie • The Microcystis-Anabaenabloom of 2009 was the largest in recent years in our sampling region • …until 2011 Source: Tom Bridgeman, UT 2011

  21. August 11 2011 1330 cfs Photo: NOAA Satellite Image

  22. October 9, 2011 Photo: NOAA Satellite Image

  23. Microcystis near Marblehead October 9, 2011 Photo: Richard Kraus, United States Geological Survey

  24. Stone Lab Docks Sept 2011

  25. Microcystin Concentrations 1 ppb WHO drinking water limit 20 ppb WHO swimming limit 60 ppb highest level for Lake Erie till this year 84 ppb highest level for Grand Lake St. Marys till last year 2000+ Grand Lake St. Marys 2010 1200 Lake Erie Maumee Bay area 2011

  26. Are HABs only a Lake Erie and Ohio Problem? Global problem Serious problem in US and Canada Common species in Lake Erie is Microcystis sp. Dominant form in Grand Lake St. Marysin 2010 was Aphanizomenon sp., the same species that bloomed in Lake Erie in the 60s and 70s

  27. Nutrient Loading Majority of loading occurs during storm events 80-90% of loading occurs 10-20% of time 2012 = dry spring and low load—a very good thing!!

  28. Climate change is making these problems worse! • Warm water favors HABs • Warm water increases oxygen depletion rates • More severe storms will resuspend more sediment and increase erosion and nutrient loading • Critically important point—with no changes in Ag practices, warmer weather and increased frequency of severe storms could increase negative impact of existing practices. • Lake levels—uncertain/probably down

  29. Increased Frequency of Rainstorms Changes in frequencies of storms in the Midwest, by category of storm size for five decades, 1961-1970 through 2001-2010. Labeled changes are for the last decade. Comparisons are to frequencies in 1961-1990. Source: Rocky Mountain Climate Organization and Natural Resources Defense Council.

  30. Maumee Discharge in 2011 & 12: the Perfect Natural Experiment

  31. NOAA HAB Forecast--2012 • Loading from March through June is critical point • Drought leads to low rainfall and runoff • Heidelberg data shows loads lowest in 40 years • UT data show Maumee Bay concentrations less than 1/10 of 2011 • Therefore, 2012 bloom will be less than 10% of 2011 bloom in Western Basin and similar to 2007.

  32. Microcystis in Lake Erie • The Microcystis-Anabaenabloom of 2009 was the largest in recent years in our sampling region • …until 2011 Source: Tom Bridgeman, UT 2011

  33. Target Loads to Solve Problem Leading subcommittee of the Ohio Phosphorus Task Force to identify both spring and annual target loads of both total P and DRP to prevent or greatly reduce HABs

  34. For more information:Dr. Jeff Reutter, Director Ohio Sea Grant and Stone Lab Ohio State Univ. 1314 Kinnear Rd. Col, OH 43212 614-292-8949 Reutter.1@osu.edu ohioseagrant.osu.edu Stone Laboratory Ohio State Univ. Box 119 Put-in-Bay, OH 43456 614-247-6500

More Related