Supplementary Material
Identifying the sources and sinks of CDOM/FDOM across the
Mauritanian Shelf and their potential role
in the decomposition of Superoxide (O2-)
Authors: Maija, I. Heller1,2, * Kathrin Wuttig1,3 and Peter L. Croot1,4
1
Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel,
Duesternbrooker Weg 20, 24105 Kiel, Germany
2
Department of Ocean Sciences, University of California, Santa Cruz, CA, United States,
[email protected]
3
Antarctic Climate & Ecosystems Cooperative Research Centre, University of Tasmania,
Private Bag 80, Hobart Tasmania 7001, Australia, [email protected]
4
Earth and Ocean Sciences, School of Natural Sciences, National University of Ireland
Galway (NUIG), [email protected]
Comprising:
9 Pages
5 Tables
1 Figure
* Corresponding Author: [email protected]
Table S1: Location of the trace metal clean sampled Goflo stations of this present study
Stn.
MSM17-4
336
352
356
382
404
454
456
491
493
514
517
525
527
541
543
592
Sampling
gear
Nr.
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
GOFLO
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Date
2011
13.03.
15.03.
15.03.
18.03.
20.03.
24.03.
24.03.
29.03.
29.03.
01.04.
01.04.
03.04.
03.04.
05.04.
05.04.
09.04.
Time
(UTC)
22:34
00:03
09:03
12:42
06:24
16:35
18:20
08:34
15:00
09:26
16:29
09:57
13:26
06:10
08:32
09:25
Coord.
Lat. ºN
12°49,990
13°59,927
14°00,187
16°11,500
18°15,299
18°12,454
18°12,453
18°11,302
18°11,301
18°11,301
18°11,252
18°09,999
18°10,056
18°13,099
18°13,040
20°20,000
Coord.
Long. °W
17°33,850
17°37,473
17°24,004
16°52,004
16°27,001
16°35,598
16°35,598
16°39,302
16°39,302
16°39,299
16°39,274
16°45,009
16°45,022
16°33,309
16°33,346
17°45,011
Bot.
depth
(m)
53
981
81
236
95
417
418
786
786
786
791
1111
1115
240
245
592
Table S2: Duration of the O2- experiments which used the thermal O2- source SOTS-1 (di(4carboxybenzyl) hyponitrite) which generate O2− at µM and continuously over several hours
(Heller and Croot, 2010a).
Goflo Stn
[SOTS-1]0 in µM
Exp Duration in h
5
1.78
23
6
1.78
10
7
1.67
10
8
0.86
9
9
1.56
10
10&11
No O2- Exp
12
1.5
9
13
1.5
8
14
1.71
6
Table S3: MSM17-4 distribution of FDOM components identified by PARAFAC
Station
5
5
5
Depth
30
45
63
C1 [RFU]
0.023
0.022
0.024
C2 [RFU]
0.013
0.013
0.012
C3 [RFU]
0.015
0.011
0.014
6
6
6
6
7
7
7
7
20
40
60
80
105
180
280
355
0.025
0.025
0.031
0.030
0.024
0.022
0.022
0.024
0.015
0.014
0.013
0.012
0.011
0.011
0.011
0.013
0.020
0.012
0.018
0.021
0.010
0.005
0.007
0.012
8
8
8
8
9
9
9
9
25
50
100
200
300
400
550
700
0.021
0.025
0.027
0.023
0.022
0.025
0.025
0.022
0.011
0.012
0.011
0.011
0.011
0.012
0.012
0.012
0.016
0.011
0.020
0.009
0.006
0.013
0.009
0.009
12
12
12
12
13
13
13
13
20
40
100
200
300
400
600
800
0.020
0.022
0.022
0.020
0.020
0.023
0.019
-
0.012
0.011
0.011
0.010
0.011
0.012
0.012
-
0.003
0.004
0
0
0.033
0
0.009
-
14
14
14
14
15
15
20
40
70
100
170
190
0.040
0.024
0.029
0.030
0.029
0.033
0.018
0.013
0.011
0.012
0.014
0.011
0.007
0.010
0.007
0.022
0.017
0.015
Table S4: MSM17-4 Superoxide decay rates using SOTS-1 as superoxide source
Station
5
5
5
Depth
30
45
63
kDTPA
0.0052 ± 0.0023
0.0071 ± 0.0035
0.0066 ± 0.0032
kSW
0.0086 ± 0.0036
0.0129 ± 0.0059
0.0127 ± 0.0062
6
6
6
6
7
7
7
7
20
40
60
80
105
180
280
355
0.0067 ± 0.0023
0.0064 ± 0.0021
0.0053 ± 0.0023
0.0058 ± 0.0026
0.0034 ± 0.0007
0.0059 ± 0.0030
0.0045 ± 0.0017
0.0049 ± 0.0019
0.0119 ± 0.0038
0.0097 ± 0.0038
0.0092 ± 0.0035
0.0104 ± 0.0044
0.0099 ± 0.0026
0.0100 ± 0.0024
0.0110 ± 0.0012
0.0099 ± 0.0024
8
8
8
8
9
9
9
9
25
50
100
200
300
400
550
700
0.0121 ± 0.0031
0.0169 ± 0.0053
0.0135 ± 0.0045
0.0137 ± 0.0018
0.0097 ± 0.0024
0.0085 ± 0.0034
0.0054 ± 0.0024
0.0067 ± 0.0029
0.0167 ± 0.0034
0.0241 ± 0.0072
0.0169 ± 0.0047
0.0207 ± 0.0015
0.0158 ± 0.0044
0.0157 ± 0.0052
0.0114 ± 0.0040
0.0122 ± 0.0045
12
12
12
12
13
13
13
13
20
40
100
200
300
400
600
800
0.0098 ± 0.0057
0.0111 ± 0.0069
0.0114 ± 0.0070
0.0114 ± 0.0072
0.0071 ± 0.0013
0.0091 ± 0.0019
0.0072 ± 0.0018
0.0098 ± 0.0020
0.0132 ± 0.0067
0.0152 ± 0.0085
0.0210 ± 0.0092
0.0215 ± 0.0116
0.0132 ± 0.0017
0.0140 ± 0.0030
0.0096 ± 0.0023
0.0122 ± 0.0028
14
14
14
14
15
15
20
40
70
100
170
190
0.0079 ± 0.0016
0.0079 ± 0.0005
0.0071 ± 0.0013
0.0084 ± 0.0006
0.0079 ± 0.0005
0.0119 ± 0.0032
0.0108 ± 0.0014
0.0090 ± 0.0009
0.0147 ± 0.0025
0.0170 ± 0.0019
Data is reported as ±1 sd.
Table S5. 2nd Order Reaction Rate Constants (M-1 s-1) for selected metal and organic species
with O2- modified after (Heller and Croot, 2010b).
Species
HO2
O2-
Cu(I)
> 1*109 (a)
~1*1010 (a)
-
9.4±0.8*109 (b)
-
1.98±0.05*109 (c)
1.2*108 (d)
1.1*1010 (d)
-
6.63 ± 0.71*108 (c)
1.2±0.5*106 (e)
7.2*108 (f)
1.2±0.2*106 (g)
1.0±0.1*107 (g)
-
1.8*108 (g)
3.1*105 (h)
1.5±0.2*108 (i)
Cu(II)
Fe(II)
Fe(III)
5.4*107 (j)
Mn(II)
2.8*107 (k)
1.7*107 (l)
8.9*106 (m)
Mn(III)
HO2
8.3±0.7*105 (n)
9.7±0.6*107 (n)
Cu(II)L
-
2.9-8.1*108 (o)
-
5±3*107 (p)
-
9.3±0.2*103 (q)
-
2.3±0.1*105 (r)
Fe(III)L
Ferulic acid
1.6*105 (s)
Gallic acid
5.4*106 (s)
Cinnamic acid
5.9*103 (s)
Caffeic acid
5.0*105 (s)
Notes: The reader is also referred to the compilation of Bielski et al. (1985). In describing the
experimental setup used in each work we use the following abbreviations: pulse radiolysis (p.r.), flash
photolysis (f.p.),  irradiation (γ-r), optical detection of superoxide (opt) and chemical detection of
superoxide or equivalent (chem.). The pKa for HO2 is 4.60±0.15 (Zafiriou, 1990). All experiments are
in the range 20-25° C.
(a)
Cu+, pH 5.3, p.r. opt. (Rabani et al., 1973).
seawater, p.r. opt. (Zafiriou et al., 1998).
(b)
Cu+, p.r. opt. (Piechowski von et al., 1993).
(c)
Cu+ and Cu++ in
(d)
Cu2+ and Cu2+-arginine, p.r, opt.(Cabelli et al., 1987). (e)Fe2+, pH 1,
p.r, opt.(Jayson et al., 1973). (f)Fe2+ and Fe3+, p.r., opt (Matthews, 1983).
(g)
Fe2+ species, pH 1-7, p.r, opt (Rush
and Bielski, 1985). (h)Fe3+ species, pH 2.74, p.r., opt (Sehested et al., 1969). (i)Fe(OH)2+ species, pH 1-7, p.r, opt
(Rush and Bielski, 1985). (j) Mn+ in sulphate, pH 7, γ-r, opt (Barnese et al., 2008). (k) Mn+ in phosphate, pH 7, γr, opt(Barnese et al., 2008). (l) Mn+ in pyrophosphate, pH 7, γ-r, opt(Barnese et al., 2008). (m)Mn3+ in phosphate,
pH 7, γ-r, opt(Barnese et al., 2008).
(n)
As summarized in Bielski et al. (1985).
complexing ligands (Voelker et al., 2000).
et al., 2000).
(o)
Natural seawater with Cu
(p)
Copper complexing ligands produced by Synechococcus (Voelker
(q)
Fe(III) complexed with desferrioxamine B in bicarbonate buffered solution (Rose and Waite,
2005). (r)Fe(III) complexed with natural organic matter in bicarbonate buffered solution (Rose and Waite, 2005).
(s)
Values from Taubert (2003)
Figure S1: Spectral characteristics of 3-component model for MSM17-4 dataset (N=253).
Highest intensities are shown in yellow.
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