Biomagnification of Monomethylmercury in Carnegie Lake
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Transcript of Biomagnification of Monomethylmercury in Carnegie Lake
Biomagnification of Monomethylmercury in Carnegie Lake
• x 104H2O
Are there differences in MMHg uptake for different species of phytoplankton? Which characteristics might be related to increased uptake?
Size FractioningTarget Group Filter pore size
Phytoplankton and particulates 0.4−20 μm
Herbivorous zooplankton >20 μm
Target Group Signal
Live Autotrophs DNA & chlorophyll
Live Heterotrophs DNA
Detritus None
Flow Cytometry
Within each site: Does the concentration of MMHg increase with increasing trophic level?
Clams Amphipods Blood worms Snails
Comparing the 5 sites: Is there a correlation between the density of phytoplankton and the concentration of mercury in the biota?
• Phytoplankton density based on fluorescence of chlorophyll (mg of chlorophyll L-1)
High Plankton Densities Reduce Mercury BiomagnificationChen & Folt, 2005
CL01 CL04 CL06 CL09 CL140
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
Total Mercury in Plankton based on Volume filtered 6/23/10
Phytoplankton 6/23/10
Zooplankton 6/23/10
Conc
entr
ation
HgT
(ng/
L)
CL01 CL04 CL06 CL09 CL140
0.5
1
1.5
2
2.5
3
3.5
4
Total Mercury in Plankton based onVolume Filtered 7/27/10
Phytoplankton 7/27/10
Zooplankton 7/27/10
Conc
entr
ation
HgT
(ng/
L)
CL01 CL04 CL06 CL09 CL140
0.5
1
1.5
2
2.5
3
3.5
4
Total Mercury in Plankton based onVolume Filtered 7/27/10
Phytoplankton 6/23/10Zooplankton 6/23/10Phytoplankton 7/27/10Zooplankton 7/27/10Co
ncen
trati
on H
gT (n
g/L)
CL01 CL04 CL06 CL09 CL140
5
10
15
20
25
30
Chlorophyll Concentration in Un-filtered Water
6/23/20107/27/2010
Chlo
roph
yll fl
uore
scen
ce
Question: Is there a correlation between the density of phytoplankton and the concentration of MMHg in the biota?
CL01 CL04 CL06 CL06 DUP
CL06 TRIP
CL09 CL140
1
2
3
4
5
6
7
8
Total Mercury 6/23/10
UnfilteredFiltered
HgT
Conc
entr
ation
(ng/
mL)
CL01 CL04 CL06 CL09 CL140
1
2
3
4
5
6
7
8
Total Hg in Water, Carnegie Lake 7/27/10
FilteredUnfiltered
Conc
entr
ation
HgT
(ng/
L)
CL01 CL04 CL06 CL09 CL140
0.5
1
1.5
2
2.5
3
3.5
Total Hg in Unfiltered WaterCarnegie Lake
Unfiltered 6/23/10Unfiltered 7/27/10
Conc
entr
ation
HgT
(ng/
L)
CONTAMINATED FILTER
Back-swimmers
Snails Amphipods Clams Limpet Fish0
20
40
60
80
100
120
140
160
180
200
Total Hg Concentration in Invertebrates & Fish
CL01CL04CL05CL06CL09CL14
Conc
entr
ation
HgT
(ng/
g)
CL01 Amphipods CL04 Amphipods CL09 Amphipods0
20
40
60
80
100
120
140
160
180
Total Hg Concentration in Amphipods
Conc
entr
ation
HgT
(ng/
g)
CL01 Spotted Sunfish
CL09 Largemouth Bass
0
20
40
60
80
100
120
140
160
180
200
Total Mercury in FishMean Mercury Concentrations in Freshwater Fish SpeciesMean concentration (ppb) Bottom FeedersCarp 110White sucker 110Channel catfish 90 Predator FishLargemouth bass 460Smallmouth bass 340Walleye 520Brown trout 140 a EPA National Study of Chemical Residues in Fish 1987;b Concentrations are reported on wet weight basisSource: Bahnick et al., 1994.
705.6 ppb HgT 312.4 ppb HgT
X 20,000
X 2
X 8
Filtere
d Wate
r
Unfiltered
Wate
r
Phytoplan
kton
Sedim
ent
Backsw
immers
Snails
Amphipods
Sunfish
0100200300400500600700800
Total Mercury at Site CL01
Conc
entr
ation
HgT
(ppb
)
Biomagnification of Total Mercury
Thanks to PEI, Dr. Eileen Zerba, Dr. Francois Morel, Frank Black, Nejma Piagentini, and my fellow interns for all your help this summer!