continued decline in lake erie water quality
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CONTINUED DECLINE IN LAKE ERIE WATER QUALITY:
INCREASING CYANOBACTERIAL BIOMASSES OVER TIME (1996-2010)
Douglas D. Kane Defiance College
Joseph D. Conroy Division of Wildlife
Ohio Department of Natural Resources
David A. Culver The Ohio State University
R. Peter Richards, David B. Baker
Heidelberg University
The Overarching Issue
Lake Erie is impaired due to excessive loadings of sediment and nutrients.
Long-term water quality monitoring has identified the Maumee River as being the largest single contributor of non-point source pollution to the lake.
From- WLEB Partnership Website
Recent Lake Erie Re-Eutrophication
TRENDS (1970’s- 2000’s) – Total Phosphorus Loading – Phytoplankton Biomass- WB – Cyanobacterial Biomass- WB
Recent Lake Erie Re-Eutrophication
Year
1965 1970 1975 1980 1985 1990 1995 2000 2005
Ext
. Tot
al P
Loa
ding
(ki
loto
nnes
)
0
5
10
15
20
25
30
WB
Tot
al P
P W
et B
iom
ass
(g m
-3)
0
1
2
3
4
5
6
Recent Lake Erie Re-Eutrophication
Year
1965 1970 1975 1980 1985 1990 1995 2000 2005
Ext
. Tot
al P
Loa
ding
(ki
loto
nnes
)
0
5
10
15
20
25
30
WB
Tot
al P
P W
et B
iom
ass
(g m
-3)
0
1
2
3
4
5
6
Recent Lake Erie Re-Eutrophication
Year
1965 1970 1975 1980 1985 1990 1995 2000 2005
Ext
. Tot
al P
Loa
ding
(ki
loto
nnes
)
0
5
10
15
20
25
30
WB
Tot
al P
P W
et B
iom
ass
(g m
-3)
0
1
2
3
4
5
6
Recent Lake Erie Re-Eutrophication
Year
1965 1970 1975 1980 1985 1990 1995 2000 2005
Ext
. Tot
al P
Loa
ding
(ki
loto
nnes
)
0
5
10
15
20
25
30
WB
Tot
al P
P W
et B
iom
ass
(g m
-3)
0
1
2
3
4
5
6
Recent Lake Erie Re-Eutrophication
Year
1965 1970 1975 1980 1985 1990 1995 2000 2005
Ext
. Tot
al P
Loa
ding
(ki
loto
nnes
)
0
5
10
15
20
25
30
WB
Tot
al P
P W
et B
iom
ass
(g m
-3)
0
1
2
3
4
5
6
Recent Lake Erie Re-Eutrophication
Year
1965 1970 1975 1980 1985 1990 1995 2000 2005
Ext
. Tot
al P
Loa
ding
(ki
loto
nnes
)
0
5
10
15
20
25
30
WB
Tot
al P
P W
et B
iom
ass
(g m
-3)
0
1
2
3
4
5
6
Recent Lake Erie Re-Eutrophication
Year
1965 1970 1975 1980 1985 1990 1995 2000 2005
Ext
. Tot
al P
Loa
ding
(ki
loto
nnes
)
0
5
10
15
20
25
30
WB
Tot
al P
P W
et B
iom
ass
(g m
-3)
0
1
2
3
4
5
6
Recent Lake Erie Re-Eutrophication
Year
1965 1970 1975 1980 1985 1990 1995 2000 2005
Ext
. Tot
al P
Loa
ding
(ki
loto
nnes
)
0
5
10
15
20
25
30
WB
Tot
al P
P W
et B
iom
ass
(g m
-3)
0
1
2
3
4
5
6
Lake Erie PP Trends: Western Basin
Year1965 1970 1975 1980 1985 1990 1995 2000 2005
Tot
al P
P B
iom
ass
(mg
L-1 )
0
1
2
3
4
5
6
7
FWMC vs. DRP
Observations
Total Phosphorus Loading not increasing, but
– Phytoplankton, Cyanobacterial blooms
– Soluble Reactive Phosphorus Loading
– And, » Dreissenid mussels now in the system » Mayflies have returned » Changing climate (i.e. more large storm events, warmer
winters etc.)
Hypothesis
Soluble Reactive Phosphorus Loading
LEADS TO Phytoplankton, Cyanobacterial blooms
Methods
SRP Load Determinations: NCWQR, HU Phytoplankton Biomass Determinations: LL, OSU Regression Analysis:
– Total PP/ Cyanobacterial Biomass vs. SRP – Cyanobacterial Biomass vs. Time
Results- Median Cyanobacterial Biomass vs. Corrected SRP Load (1996-2006)
Maumee R. SRP-load (metric tonnes)
0 250 500 750 1000
WB
Cya
no (
wet
mg
L-1)
0102030405060708090
100 P < 0.001 r2 = 0.80
Results- Seasonal Average Biomass vs. Uncorrected SRP Load (1996-2006)
Maumee R. SRP-load (metric tonnes)
0 100 200 300 400 500 600 700
WB
Tot
al P
P (
wet
mg
L-1)
0
10
20
30
40
50
60
70
Maumee R. SRP-load (metric tonnes)
0 100 200 300 400 500 600 700
WB
Cya
no (
wet
mg
L-1)
0
10
20
30
40
50
60
70
P = 0.008 r2 = 0.56
P = 0.008 r2 = 0.56
Results- Seasonal Average Biomass vs. Uncorrected SRP Load (1996-2006)
Maumee R. SRP-load (metric tonnes)
0 100 200 300 400 500 600 700
WB
Tot
al P
P (
wet
mg
L-1)
0
10
20
30
40
50
60
70
Maumee R. SRP-load (metric tonnes)
0 100 200 300 400 500 600 700
WB
Cya
no (
wet
mg
L-1)
0
10
20
30
40
50
60
70Maumee + Sandusky R. SRP-load
0 100 200 300 400 500 600 700 800
WB
Tot
al P
P (
wet
mg
L-1)
0
10
20
30
40
50
60
70
Maumee + Sandusky R. SRP-load
0 100 200 300 400 500 600 700 800
WB
Cya
no (
wet
mg
L-1)
0
10
20
30
40
50
60
70
P = 0.007 r2 = 0.57
P = 0.008 r2 = 0.56
Results- Seasonal Average Biomass (no >95% values) vs.Time (1996-2011)
Year
1996 1998 2000 2002 2004 2006 2008 2010
WB
Cya
no (
wet
mg
L-1 )
0
2
4
6
8
10
P = 0.006 r2 = 0.46
P = 0.002 r2 = 0.55
Western Lake Erie Waterkeeper Association
Conclusions
NASA
NASA
October 2011
September 2011
Reasons for SRP Increase??
DWWTP (Detroit Wastewater Treatment Plant) CSOs (Combined Sewer Overflows) CAFOs (Concentrated Animal Feeding Operations) UFOs (Unidentified Fertilizing Objects)
– Timing of Fertilizer Application – Rate “ “ – Type “ “ – Amount “ “
Exurbanization Septic Systems Saturated Filter Strips Climate Change All of These None of These
Acknowledgements
Dave Dolan- UWGB- Total Phosphorus Loading Data Limnology Laboratory Personnel- OSU National Center for Water Quality Research
Personnel- HU
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