Algae are tiny plant-like like organisms that live in water There are hundreds of species of algae in Lake Erie, Most are beneficial

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1 Harmful Algal Blooms in Western Lake Erie Thomas B. Bridgeman, University it of Tld Toledo (and graduate students)

2 Algae are tiny plant-like like organisms that live in water There are hundreds of species of algae in Lake Erie, Most are beneficial

3 Too much of the wrong kind of algae is harmful Bloom is an excessive amount of algae Harmful algae bloom is a bloom of potentially harmful algae.

4 Major groups in Lake Erie Diatoms Greens Blue-greens (Cyanobacteria)

5 Blue-green Algae in Lake Erie Anabaena Aphanizomenon Microcystis

6 Increase of algae 1920 to 1964 Lake Erie algae biomass increased nearly 6 fold. Diatoms replaced by cyanobacteria Phosphorus determined d to be the source of the problem. Davis 1964

7 Lake Erie Recovers Phosphorus loading reduced during 1970 s Resulted in less total algae Cyanobacteria nearly absent during 1980 s and early 1990s. Conroy & Culver 2005

8 Algae increases and cyanobacteria return Algae Conroy & Culver 2005

9 Algal blooms have been getting worse over the past 15 years 3 major problem species in the Great Lakes Microcystis aeruginosa Cladophora spp. Lyngbya wollei

10 Why should we care? Harmful Algal Blooms = Toxins Microcystis produces microcystin If ingested, toxin damages the liver -Brazil 1988: 2000 sick, 88 deaths when reservoir developed Microcystis bloom -Brazil 1996: Deaths of 55 dialysis patients when clinic used water contaminated with microcystin toxin -many animal poisonings i W. Carmichael

11 Skin contact may cause allergic rash Economic Costs City of Toledo spends an extra $3,000 to $4,000 per day to treat drinking water during Microcystis blooms

12 Microcystis bloom August 2003 Toledo Water Intake landsat

13 Generally Unpleasant Rotten smell, fouled beaches May contribute to the dead zones Decomposition of algae consumes oxygen

14 Lyngbya wollei wollei in western Lake Erie First noticed in Lake Erie in fall of 2006, now a big problem

15 Lyngbya grows in benthic mats A. Pinowska Florida springs, 2003

16 Lyngbya mats grow on the bottom for most of the summer. In late summer, the mats break loose and float to the surface. Strains of Lyngbya wollei in southeast US are known to produce potent neurotoxins Toxin production has not been found in Lake Erie Lyngbya Maumee Bay State Park, Lake Erie October 2007

17 Lynbya wollei mats washed ashore near in Fall 2006 ~200 tons cover just 100 m of shoreline Dr. Thomas Bridgeman

18 Fall 2007 Floating mats about 5 miles offshore

19 Submerged Lyngbya mats, August 2010

20 Factors that promote Harmful Algal Blooms (Microcystis and Lygnbya) High g nutrient loading from tributaries (Phosphorus and Nitrogen) High turbidity?

21 Maumee River Watershed USGS

22 Land Use Highly Agricultural USGS

23 Total Phosphorus has not changed D. Baker, NCWQR

24 The type of phosphorus p has changed Dissolved reactive P has increased National Center for Water Quality Research, Heidelberg University

25 Microcystis in Lake Erie The Microcystis bloom of 2009 was the largest in recent years in our sampling region

26 Phosphorus vs. Microcystis time series analysis Data from : 2009: Deviation from Long- term mean The best predictor of Microcystis biovolume is dissolved reactive P loading 4-8 weeks prior Therefore, not just the annual P load, but the timing of delivery is important

27 Observations Bloom matches the turbidity plume Aug Sept Turbidity plume promotes Microcystis growth MODIS

28 Conditions in the Turbidity plume Hypothesis: High suspended sediments Favor Cyanobacteria blooms Photo credit: Roger Knight

29 How does turbidity favor Microcystis?? Microcystis can be highly buoyant Mixed plankton After 1 Hour After 1 Day

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31 Maumee Bay light zones Inner Mid Outer

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34 Lake Sites GR 1 8M MB18 7M 4P MB 20

35 Summary of Turbidity and Lake Mixing Results Twineline = Microcystis

36 LEAST Project 2009 (Lake Erie Algal l Source Tracking) I. Determine the relative contribution of the Maumee River system and lake sediments as a source of algal biomass leading to Microcystis blooms in western Lake Erie. Extensive lake river - sediment sampling on 3 dates (before bloom, incipient bloom, mid-bloom) Microcystis BLOOM River Lake

37 LEAST Sampling 5 Maumee River sites 6 Lake sites (plus accessory sites & dates) Dates: June 16, August 6, September 11 (Waterville sampler July 9 Sept. 18 alt days) T1= The Bend T2 = Rt. 66 Bridge T3 = Independence Dam T4 = Mary Jane Thurston State Park T5= Farnsworth Metropark

38 Objectives of LEAST Project II. Determine how phosphorus in western Lake Erie is partitioned into various categories. SRP & TP River Microcystis P Seston P (>112 um) Seston P (<112 um) Lyngbya P BLOOM SRP DOP (Dissolved organic P ) Lake

39 Objectives of LEAST Project III. Lyngbya wollei distribution, seasonal growth, habitat

40 River-Lake Algae Trends June: Green algae is dominant in River and Lake Blue-greens (Microcystis) are substantial in river but not in lake

41 River-Lake Algae Trends August: Greens and Diatoms dominant in river Blue-greens (Microcystis) dominant in lake

42 River-Lake Algae Trends September: Overall algae decrease (except Farns) Blue-greens still dominant in lake (Microcystis)

43 Microcystis Conclusions Maumee River and lake sediments identified as potential sources of L. Erie Microcystis Microcystis appears in the river before it does in the lake. Present in all locations (except lake water) in earliest sampling

44 Phosphorus Tracking

45 Phosphorus Trends: June 2009 High P at all river sites, decreasing into lake Most P is in form of DOP at all sites Low Particulate t P High DRP in River, low in lake

46 Phosphorus Trends: Aug 2009 Increasing TP downriver, decreasing into lake Low DRP at all sites (except furthest upriver)

47 Phosphorus Trends: Sept 2009 Similar TP at river sites, decreasing into lake Increase in DRP and DOP at lake sites Breakdown of Bloom?

48 P partitioning: Microcystis Particulate P partitioned into greater/ less than 112 um size. Further partition >112um fraction into Microcystis and other (zooplankton, diatoms) Microcysis P is always a small %, therefore all algal P in Aug and Sept is a small % What is <112 um particulate P? (sus sediment, bacteria, microzoop?) JUNE AUG SEPT

49 Lyngbya wollei density in western Lake Erie

50 Phosphorus contained in Lyngbya 40 increases from June - August Aver rage Pho osphorus s content t of Lyngb bya (mgp P/m 2 ) Month Jun-09 Jul-09 Aug-09

51 On average, about 18% of phosphorus per square meter in western Lake Erie is contained in Lyngbya. y In dense mats, Lyngbya may contain ~4x more P than the water column 200 mg P 200 mg P 32 mg P 900 mg P 1 m

52 Conclusions There is a lot of phosphorus, but most water column P is in dissolved or small particle form (not Microcystis, diatoms, or zooplankton) Given that Microcystis is usually P-limited, rates of conversion from DOP and small seston P to DRP may be important On average, about 18% of phosphorus p per square meter in western Lake Erie is contained in Lyngbya, a new compartment. SRP & TP River Microcystis P Seston P (>112 um) Seston P (<112 um) Lyngbya P BLOOM SRP DOP (Dissolved organic P ) Lake

53 Other Projects Biofuels from Lake Erie Algae Improved remote sensing of algal blooms Continuous Monitoring

54 Acknowlegements Patricia Armenio Peter Bichier Christopher Bronish Justin Chaffin Sarah Panek Christine Mayer Doug Kane Joe Conroy