Understanding and Monitoring Harmful Algal Blooms in Freshwaters
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Transcript of Understanding and Monitoring Harmful Algal Blooms in Freshwaters
Understanding and Monitoring Harmful Algal Blooms in
Freshwaters
Elena LitchmanMichigan State University and
Kellogg Biological Station
Fresh Water is a Limited Resource•Only 2.5% of water on Earth is fresh•2/3 is locked in glaciers and polar ice caps
http://eospso.gsfc.nasa.gov/ftp_docs/water_litho.pdfhttp://www.unep.org/themes/Freshwater/Related_Links/index.asp
Fresh Water is a Limited ResourceUSA Today, October 19, 2007
Not only water quantity, but water quality!
Water quality problem: Harmful Algal Blooms (HABs)
Talk Outline
•General Information on HABs
•The role of global change in HAB proliferation
•Current research on global change and HABs in my lab
HAB Phytoplankton Cyanobacteria (freshwater and marine)
Harmful Algal Blooms (HABs)
http://www.keweenawalgae.mtu.edu/ALGAL_IMAGES/cyanobacteria/
http://www.ab.lst.se/
Atmospheric nitrogen fixation
http://www.botan.su.se/Fysiologi/CYANO/SUB-2.HTM
Cyanobacteria in Temperate Lakes Main Players
Anabaena
Aphanizomenon
Microcystis
Planktothrix
Cyanobacterial Toxins
Microcystins - produced by Microcystis, Planktothrix (Oscillatoria), Anabaena
Babica et al. J. Phycol. 2006sigmaaldrich.com
•Hepatotoxins
•Neurotoxins
Differ in toxicity
LR YR
Global Change and HABs
Global Change Effects on Cyanobacteria
•Increased air and water temperature Directly stimulates growth
•Longer ice-free periodStimulates growth
•Increased stratification (stability of the water column)Increases competitive advantage (buoyancy)
•Decreased mixingIncreases competitive advantage (buoyancy)
•Increased nutrient limitationMay increase competitive advantage (N-fixers)
•Increased oxygen depletion (at the bottom)
Interaction of Multiple Global Change Stressors
•Invasive Species
HAB-forming cyanobacteria
Zebra mussels
•Increased Nutrient Inputs
•Increased Pesticide Inputs
Cyanobacteria in Temperate Lakes Invasive Newcomer
Cylindrospermopsisraciborskii
•Invasive•Fixes N•Produces toxins•Forms deep chlorophyll maxima
cylindrospermopsin
Global Change and HABs
Frequency and severity of HABs will likely increase in the future!
Current Work on HABsin my Lab
Lab members participating in HAB research
Mary Anne EvansKohei YoshiyamaJarad MellardAlly MorganPam WoodruffKelly AmrheinPaula Tezanos
Current HAB Work in my Lab
• Field sampling of diverse lakes in MI
• Lab experiments (physiology, competitive interactions)
• Modeling interactions between HAB species and the rest of the plankton
Field Sampling
– Monitor and sample diverse lakes in West Michigan
– Characterize physical structure of the water column (temperature, light, turbulence)
– Measure chemical parameters (nutrients) – Determine phytoplankton community
structure (HAB species)– Measure toxins (microcystin)
Field Sampling and Monitoring Sites
Current sampling
Proposed sampling
Detailed Physical Structureof Diverse Lakes
•SCAMP (Self-Contained Autonomous Microprofiler)#46•Moored thermistor chains
•Temperature•Light•Chl fluorescence•Turbulence•Stratification/mixing
Seasonal Chl Distribution
Depth and Seasonal Variation in Turbulence
Gull Lake. MI051015202510-810-610-410-2100102
a) June 28, 2006
Depth (m)
Kz (cm2 s-1)
ML depthMedian Kz = 3.5 cm2 s-1KPAR=0.24 m-1
051015202510-810-610-410-2100102
b) August 10, 2006
Kz (cm2 s-1)
ML depth
Median Kz = 0.13 cm2 s-1KPAR=0.36 m-1
051015202510-210-1100101102103104
c) November 1, 2006
Kz (cm2 s-1)
Median Kz = 161 cm2 s-1KPAR=0.25 m-1
Lowest turbulenceHighest Microcystis abundance
Monitoring Cyanobacteria •Abundance•Toxin concentration
survey lakes, MI
-0.1
0.1
0.3
0.5
0.7
0.9
1.1
1.3
1.5
0 10 20 30 40 50 60 70
TP (ug/L)
microcystin conc. (ug/L)
no ZMZM
Presence of Invasive Species Gull Lake, MI
0
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29-Jun-07 19-Jul-07 8-Aug-07 28-Aug-07 17-Sep-07 7-Oct-07 27-Oct-07
date
microcystin conc. (ug/L)
Physical processes
Evans et al. in prep.
Lake Monitoring Networks
• GLEON (Global Lake Ecological • Observatory Network)• WATERS Network( Water and Environmental Research System)• CUAHSI (Consortium of Universities for the
Advancement of Hydrologic Science)
Parameters to measure:Physical, chemical and biological