spatial variation in methylation rates in farmington and ogden bays ms. abigail rudd, dr. diego...
TRANSCRIPT
Spatial variation in methylation rates in
Farmington and Ogden Bays
Ms. Abigail Rudd, Dr. Diego Fernandez,
Mr. Greg Carling, Prof. William Johnson
University of Utah, Geology & Geophysics
Funded by Forestry, Fire, and State Lands
0
2
4
6
8
10
12
14
16
18
20
DO
(m
g/L
)
x
7.8
8.0
8.2
8.4
8.6
8.8
9.0
9.2
9.4
pH
x
DO
pH
1.20
1.40
1.60
1.80ug/L
x
Se
0.00
1.00
2.00
3.00
4.00
0 5 10 15 20
Time (MST)
ng/L
x
Hg
1200 1600 2000 0200 0600 1200
Selenium & Mercury at Ambassador Duck Club
Greg Carling University of Utah
Howard Slough outfallJuly 23-24, 2008
Ambassador W-1 outletAugust 20-21, 2008
(Howard Slough data from David Naftz)
methylHg
(ng/L)
0.03
0.05
0.07
0.09
0.11
0.13
1300
1400
1500
1600
1700
1800
1900
2000
2100
2200
2300
2400
0100
0200
0300
0400
0500
0600
0700
0800
0900
1000
1100
1200
GunnisonBay
Bear River Bay
Bear River
GilbertBay
Weber River
Jordan River
OB-1
OB-2
OB-3OB-4
OB-5
Ogden Bay
Farmington Bay
auto causeway opening (bridge)
FBN-1
FBN-2FBN-3
FBN-4
FBN-5
Jordan River
FBS-1FBS-2
FBS-3FBS-4
FBS-5
TotalHg
MethylHg
TotalHg
MethylHg
Hg2+
spike
Initial sample Spike Later sample
MeHg = 30%Extraction efficiency not consistent
enough to reliably measure
MeHg
204
TotalHg
MethylHg
202
TotalHg
MethylHg
204Hg2+
spike
Me204Hg
Me204Hg is 300%Can reliably measure
Initial sample Spike Later sample
HgMekHgMeHgTkdt
HgMeddemethmeth
204204204204
tMeHgktMeHgTHgkMeHg
tMeHgktMeHgTHgkMeHgtR
tdemethtmetht
tdemethtmethtMeHg
2041
2041
2041
2021
2021
2021204/202 )(
HgMek
HgMek
HgMeHgTk
HgMeHgTk
HgMe
HgMe
dt
dR
dt
d
demeth
demeth
meth
methMeHg 204
202
204204
202202
204
202204/202
0
1
2
3
4
5
0 20 40 60 80
R2
02
/20
4M
eH
gFBN-1 summer
simulated
Measured
Control
0
1
2
3
4
5
0 20 40 60 80
R2
02
/20
4M
eH
g
hours
FBN-2 fall
0
1
2
3
4
5
0 20 40 60 80
FBS-3 fall
0
1
2
3
4
5
0 20 40 60 80
hours
OB-2 summer
Summer
0.0E+00
2.0E-04
4.0E-04
6.0E-04
8.0E-04
1.0E-03
kmeth(hrs-1)
OB Summer
0.0E+00
5.0E-04
1.0E-03
1.5E-03
kmeth
(hrs
-1)
FBN Fall
1.4E-6
0.0E+00
4.0E-06
8.0E-06
1.2E-05
1.6E-05
kmeth
(hrs
-1)
FBS Fall
0.0E+00
1.0E-04
2.0E-04
3.0E-04
kmeth
(hrs
-1)
FBN Summer
0.0E+00
5.0E-03
1.0E-02
1.5E-02
2.0E-02
kdemeth
(hrs
-1)
10%
15%
20%
25%
30%
FBN-1 FBN-2 FBN-3 FBN-4 FBN-5
Org
an
ic M
att
er
(% L
OI)
0.0E+00
1.0E-02
2.0E-02
3.0E-02
kdemeth
(hrs
-1)
10%
15%
20%
25%
30%
35%
FBN-1 FBN-2 FBN-3 FBN-4
Org
an
ic M
att
er
(%L
OI)
0.0E+00
4.0E-05
8.0E-05
1.2E-04
kdemeth
(hrs
-1)
0%
5%
10%
15%
20%
25%
FBS-1 FBS-2 FBS-3 FBS-4 FBS-5
Org
an
ic M
att
er
(%L
OI)
0.0E+00
1.0E-02
2.0E-02
3.0E-02
4.0E-02
kdemeth(hrs-1)
0%
5%
10%
15%
20%
OB-1 OB-2 OB-3 OB-4 OB-5
Org
an
ic M
att
er
(% L
OI)
0
2
4
6
8
10
0
50
100
150
200
FBS-1 FBS-2 FBS-3 FBS-4 FBS-5
Me
Hg
(ng
/L)
TH
g (n
g/L
)
FBS Summer (<10 cm water column)
THg
MHg
0
0.1
0.2
0.3
0.4
0
20
40
60
80
100
FBN-1 FBN-2 FBN-3 FBN-4
Me
Hg
(ng
/g)
TH
g (n
g/g
)
FBN Fall
THg
MHg
0
0.1
0.2
0.3
0.4
050
100150200250300
FBS-1 FBS-2 FBS-3 FBS-4 FBS-5
Me
Hg
(ng
/g)
TH
g (n
g/g
)
FBS Fall
THg
MHg
0
0.1
0.2
0.3
0.4
0
20
40
60
80
100
OB-1 OB-2 OB-3 OB-4 OB-5
Me
Hg
(ng
/g)
TH
g (n
g/g
)
OB Summer
THg
MHg
0
2
4
6
8
10
0
5
10
15
20
25
30
OB-1 OB-2 OB-3 OB-4 OB-5
Me
Hg
(ng
/L)
TH
g (n
g/L
)
OB Summer (<10 cm water column)
THg
MHg
0
2
4
6
8
10
0
5
10
15
20
FBN-1 FBN-2 FBN-3 FBN-4
Me
Hg
(ng
/L)
TH
g (n
g/L
)
FBN Fall (>0.6 fractional depth)
THg
MHg
0
2
4
6
8
10
0
5
10
15
20
FBN-1 FBN-2 FBN-3 FBN-4 FBN-5
Me
Hg
(ng
/L)
TH
g (n
g/L
)Water Column
FBN Summer (>0.5 fractional depth)
THg
MHg
0
0.1
0.2
0.3
0.4
0
20
40
60
80
100
FBN-1 FBN-2 FBN-3 FBN-4 FBN-5
Me
Hg
(ng
/g)
TH
g (n
g/g
)
SedimentFBN Summer
THg
MHg
R² = 0.8953
R² = 0.8794
R² = 0.6717
0.0E+00
2.0E-04
4.0E-04
6.0E-04
8.0E-04
1.0E-03
1.2E-03
0% 5% 10% 15% 20% 25% 30% 35% 40%
kmeth
(hr-1
)
Organic matter content (%LOI)
FBN Summer
FBN Fall
OB Summer
• Spatial variability occurs for methyl Hg concentrations and Hg methylation potentials
• Methyl Hg and total Hg concentrations do not correspond to methylation rates
• Initial results tie Hg methylation rates to organic matter content
Summary
FBN Summer - Shallow (<0.7 fractional depth)
0
5
10
15
20
FBN-1 FBN-2 FBN-3 FBN-4 FBN-5
FBN Summer - Deep (>0.8 fractional depth)
0
5
10
15
20
FBN-1 FBN-2 FBN-3 FBN-4 FBN-5
DO (mg/L)
Sulfate (g/L)
Conductivity (mS/cm)/10
FBN Fall - Deep (>0.6 fractional depth)
0
5
10
15
20
FBN-1 FBN-2 FBN-3 FBN-4
FBS Summer <10 cm water column depth
0
5
10
15
20
FBS-1 FBS-2 FBS-3 FBS-4 FBS-5
OB Summer <20 cm water column depth
0
10
20
30
40
OB-1 OB-2 OB-3 OB-4 OB-5