Embed Size (px)
DESCRIPTION
Assessment tools to remove BUIs are inconsistent across the Great Lakes’ AOCs. This study assesses two BUIs, Degraded Benthos and Degraded Plankton Communities, using a design that compares AOCs to non-AOCs. Using non-AOC sites to determine if BUIs are still degraded, decisions can be made based on “control” sites.
Citation preview
Menomonee River 1
Assessment of Beneficial Use Impairments for
Benthos and Plankton in Wisconsin’s Lake Michigan AOCs
Amanda Bell
US Geological Survey, Middleton, WI
In cooperation with the
Wisconsin Department of Natural Resources
US Geological Survey
Fox River 2
Background
• All of the AOCs along Wisconsin’s Lake Michigan shoreline have degraded benthos and three (not Menominee) have degraded plankton
• Consistent/comparable legacy community data for these sites doesn’t exist
• Stage 2 RAPs were due and TACs needed to identify projects that would address targets
• Wisconsin DNR and USGS designed a comparative study to assess plankton and benthos communities in AOCs and non-AOCS
US Geological Survey
Milwaukee Harbor 3
Questions
• What is the current state of benthic invertebrate and plankton communities in Wisconsin's Lake Michigan AOCs?
• How do the benthos and plankton communities in these AOCs differ from rivers that are not considered AOCs?
• What community measures (i.e. IBI, richness, abundance, diversity) can be used as guides for determining benthos and plankton impairment in the AOCs?
US Geological Survey
Sheboygan River 4
Sampling Design
• 10 Sites/3 times in 2012– 4 Wisconsin Lake Michigan AOCs
• Menominee River• Fox River/Green Bay (two river sites)• Sheboygan River (Replicate)• Milwaukee Estuary (two river sites, one harbor site)
– 6 Lake Michigan non-AOCs• Escanaba River• Oconto River• Anapee River (Algoma)• Kewaunee River• Manitowoc River (Replicate)• Root River (Racine)
US Geological Survey
5US Geological Survey
Area of Concern
Non-AOC
Oconto River 6
Sampling Scheme
• Plankton–Water Depth Profile– 63 µm Plankton Tow
• Benthos– Hester-Dendy Sampler– Ponar Dredge
US Geological Survey
Menominee River 7
Water Depth Profile Sample
• Water sample (about 1 liter) from each meter of water depth down to 5 meters
• 3 times during growing season– June, July/August, September
• Identification/Enumeration at WSLH (soft algae) and by Paul Garrison, WDNR (diatoms)
• Chlorophyll a and Biomass analyzed at WSHL
US Geological Survey
Milwaukee River 8
Plankton Tow Samples
• Vertical tow with 63-µm plankton net• 1-5 tows to obtain total of 5 meters of depth• Identification/Enumeration by Paul Garrison,
WDNR
US Geological Survey
9
Hester Dendy Samples
• 3 per sampling location (15 total)• Deployed end of April– Retrieved June, redeployed– Retrieved July/August, redeployed– Retrieved September
• Identification/Enumeration at UW Superior
Menominee RiverUS Geological Survey
Kewaunee River 10
Ponar Dredge Samples
• 3-5 dredges composited per sampling location (depending on substrate) near Hester Dendys
• 3 times during growing season– June, July/August, September
• Identification/Enumeration at UW Superior• Sediment size analysis at WSLH• Volatile on Ignition analysis by USGS
US Geological Survey
Anapee River 11
Data Analysis
• Once data come back from lab (fall/winter 2012)–Macroinvertebrate Community assemblage
analysis• IBI Scores• Determine species composition differences between
sites• Multivariate statistics
US Geological Survey
Milwaukee River 12
Data Analysis
• Site to site comparison– Benthos using WI Larger River IBI– Plankton using Shannon Diversity Index– For each season, if the AOC is less than 10% OR
one stand deviation (of all non-AOC sites) of selected comparison sites, then the seasonal sampled will be deemed degraded.
– If it is degraded two or more seasons, the benthos or plankton for the site is deemed degraded.
US Geological Survey
Escanaba River 13
Data Analysis
• Overall comparison– Multivariate analyses designed for multiple sites with
similar multiple samples (seasons)• Tests if there is difference between groups (AOC vs. non-
AOC sites)• Tests if there is difference between multiple groups (sites or
seasons)
– Determine what species/metrics differ between AOC and non-AOC
– Deemed significantly different with a 90% confidence cut-off (p-value <10%)
US Geological Survey
Kewaunee River 14
Future Questions
• Is there a significant difference in the plankton (and benthos) communities between each AOC and the non-AOCs?
• Which species, whether their present or absent, are indicative of systems that are NOT considered “degraded”?
US Geological Survey
Manitowoc River 15
Questions?
US Geological Survey
Root River 16
Contact Info
• Amanda Bell– US Geological Survey, Middleton, WI– [email protected]– 608-821-3882
US Geological Survey
