Dynamics of cyanobacterial bloom formation

Justin Chaffin Ph.D.F.T. Stone Laboratory

Ohio Sea GrantThe Ohio State University

chaffin.46@osu.edu

HABs 101Tom Ridge Environmental Center, August 14, 2013

There are hundreds of species of algae in Lake Erie

Lake Erie food web

Bottom organisms

Major phytoplankton groups in Lake Erie

• Diatoms• Glass cell wall• High lipid content• Nutritional for zooplankton• Spring blooms of diatoms in Lake

Erie

http://cfb.unh.edu/

Lake Erie diatom bloom during winter

Twiss et al., 2012 J Great Lakes Res.

Major phytoplankton groups in Lake Erie

• Green Algae• Closely related to higher plants• Account for 50% of species in

Lake Erie• Rarely bloom• Less lipid, but nutritious

http://cfb.unh.edu/

Cladophora

Cladophora chloroplast

Cladophora epiphytes

Cladophora chloroplast

Major phytoplankton groups in Lake Erie

• Cyanobacteria• “Blue-green algae”• Some contain gas vacuoles• Some produce toxins• Some fix nitrogen• Low lipid, low nutrition• Just a few are “Harmful”

– Synechococcus ~ 50% of oxygen

http://cfb.unh.edu/

Other algae of Lake Erie

http://cfb.unh.edu/phycokey/phycokey.htm

Lake Erie produces the most fish of all the Great Lakes because it has the most algae

• Highest nutrient concentrations• Warmest water temperature

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.

Photo Credit: Drs Jeff Reutter and Doug Kane

What is a Harmful Algal Bloom?

• Harmful = – Has the potential to produce toxins.– Harmful impacts on ecosystems

• Algal =– Blue-green algae (cyanobacteria)– Red tide (dinoflagellates)

• Bloom = – Biomass that far exceed normal Hungeree.com

geology.com

Are there non-harmful algal blooms?

• Cladophora• Diatoms

• These algae can reach high biomasses but do not produce toxins harmful to humans or animals – But can have other negative

impacts

Turtles.org

Not an algal bloom:• Duckweed• Lily pads• Submerged plants• Lawn clippings

Algal blooms are a global problem• Due to humans increasing nutrient loading

Lake Taihu, ChinaLake Nieuwe Meer, Netherlands

Lake Erie, USA

Problems associated algal blooms

• “Blooms” of cyanobacteria– Produce toxins– Low diversity of phytoplankton

• Taste and smell problems• Low dissolved oxygen• Property value decreases• Negative economic impacts

whoi.edu, W. Carmichael

geolocation.ws

High phosphorus concentrations are required for eutrophication

+ Carbon+ Nitrogen+ PhosphorusDense algae bloom

+ Carbon+ NitrogenNo Phosphorus addedNo algae bloom

Schindler 1974. Science

Bloom requirements

• Water temperatures > 15 °C– July, August, September in Lake Erie

• High nutrient concentrations– Run off associated with rain storms– Phosphorus typically is the “limiting nutrient”– Nitrogen is important in cyanotoxin production

Lake Erie cyanobacteria blooms

MODIS

Lake Erie 2011

Microcystis is the major blue-green algae in Lake Erie

http://cfb.unh.edu/phycokey/phycokey.htm

Microcystis

http://cfb.unh.edu/phycokey/phycokey.htm

Microcystis

http://cfb.unh.edu/phycokey/phycokey.htm

Anabaena common late summer

http://cfb.unh.edu/phycokey/phycokey.htm

Non-blooming Cyanobacteria in Lake Erie

Merismopedia Chroococcus

http://cfb.unh.edu/phycokey/phycokey.htm

Lake Erie blooms have been typically confined to western Lake Erie: Microcystis

landsat

Lake Erie 2011A) June 1B) July 19C) July 31D) August 11E) September 3F) October 9

Michalak et al. 2013 PNAS

Variation in Microcystis bloom intensity of Lake Erie

2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 20120

5000

10000

15000

20000

25000

30000

35000

40000

Year

Mic

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stis b

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L/m

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Bridgeman et al., 2013. Journal of Great Lakes Research

2011 Record-breaking bloom explained

Maumee River spring phosphorus load explains the size of the bloom

Stumpf et al. 2012 PloS One

Most P loading occurs during storms

Michalak et al. 2013. Proc Nat Acad Sci

Calm summer increased residence time of Maumee Bay

• Spring storm water sat in Maumee Bay during summer and provide the perfect incubator for cyanobacteria.

Michalak et al. 2013. Proc Nat Acad Sci

Calm water favors Microcystis

• Microcystis wins in calm water and deeper water

• Diatoms win in mixed water

Huisman et al. 2004

Mix

edCa

lm

TurbidClear

Photo credit: Roger Knight

2011 Record-breaking bloom explained

• Many large spring storms• High P loading

– Fertilized growth• Very calm early summer

– Microcystis floated and thrived– Diatoms sank and died

Other cyanobacteria blooms

Sandusky Bay

Planktothrix in Sandusky Bay

http://cfb.unh.edu/phycokey/phycokey.htm

Sandusky Bay – July 2012

Central basin Anabaena bloom

Benthic Lyngbya in Maumee Bay

Lyngbya

http://cfb.unh.edu/phycokey/phycokey.htm

Lyngbya at Stone Lab. August 20 2012

Lyngbya at Stone Lab. August 20 2012