Does temperature affect phytoplankton size structure in ...
Transcript of Does temperature affect phytoplankton size structure in ...
Does temperature affect phytoplankton size structure in the ocean?
E. Marañón1, P. Cermeño1, M. Latasa2, R. D. Tadonléké3
aUniversidade de Vigo, Vigo, Spain bInstituto Español de Oceanografía, Gijón, Spain
cInstitut National de la Recherche Agronomique, Thonon les Bains, France
Figure from Finkel et al 2010
The importance of phytoplankton size structure
Phytoplankton dominated by:
Property Small cells Large cells
Dominant trophic pathway Microbial food web Classic food chainMain loss process for phytoplankton Grazing by protists Sinking and grazing
by metazoansPhotosynthesis-to-respiration ratio ~1 >1f-ratio and e-ratio 5–15% >40%Main fate of primary production Recycling Export toward deep
in the upper layer waters
% microphytoplankton chl a% picophytoplankton chl a
[DIN
] (nM
) at w
hich
cel
ls
beco
me
diffu
sion
-lim
ited
The size-dependence of nutrient acquisition can explain the
biogeography of phytoplankton size classes… M
arañ
ón 2
009
Hirata et al 2011
µ=
µ=
…but separating the effects of temperature and nutrients can be difficult because they are strongly correlated in the ocean
Goes et al. 1999
Surface waters, Pacific Ocean
Recent studies suggest a direct effect of temperature on phytoplankton size structure
V d
iffer
ence
from
V15
°C/ V
15°C
Temperature difference from 15°C
The temperature-size rule: cell volume in protists decreases ~2.5% per °C of warming (Atkinson et al 2003)
Atkinson et al 2003
Objectives
• To test the hypothesis that temperature per se plays a role in controlling phytoplankton size structure in the ocean
• To assess the relative importance of temperature versus resources in the control of phytoplankton size structure
Approach
To obtain a large data set of measurements of size-fractionated chl a in all combinations of temperature and resource supply conditions
Temperature
Nut
rien
ts
HIG
HLO
W
COLD WARM
Temperature
Nut
rien
ts
HIG
HLO
W
COLD WARM
Approach
To obtain a large data set of measurements of size-fractionated chl a in all combinations of temperature and resource supply conditions
Data compilation: temperature, size-fractionated chl a and primary production in cold (<10°C), temperate (10-20°C) and warm (>20°C) waters
Chl a map: SeaWiFS Project/NASA
Total Chl a concentration (µg L-1)
0.01 0.1 1 10 100
Size
-frac
tiona
ted
Chl
a (µ
g L-1
)
0.0001
0.001
0.01
0.1
1
10
100picophytoplanktonnanophytoplanktonmicrophytoplankton
All data (n = 500)
General relationship between total and size-fractionated chl a
0.2-2µm2-20µm>20µm
Total Chl a concentration (µg L-1)
0.01 0.1 1 10 100
Size
-fra
ctio
nate
d C
hl a
(µg
L-1)
0.0001
0.001
0.01
0.1
1
10
100picophytoplanktonnanophytoplanktonmicrophytoplankton
Total Chl a concentration (µg L-1)
0.01 0.1 1 10 100
Size
-fra
ctio
nate
d C
hl a
(µg
L-1)
0.0001
0.001
0.01
0.1
1
10
100
Cold Temperate
Similar patterns in regions with different temperatures
n = 153 n = 165
Total Chl a concentration (µg L-1)
0.01 0.1 1 10 100
Size
-fra
ctio
nate
d C
hl a
(µg
L-1)
0.0001
0.001
0.01
0.1
1
10
100
Warm n = 182
0 5 10 15 20 25
% P
icop
hyto
plan
kton
Chl
a
0
20
40
60
80
100coldtemperatewarm
0 5 10 15 20 25
% N
anop
hyto
plan
kton
Chl
a
0
20
40
60
80
100
Total Chl a concentration (µg L-1)
0 5 10 15 20 25
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
Pico Nano
% Chl a in each size class strongly dependent on total Chl a
coldtemperatewarm
0 1 2
020406080
100
Microy = 92.3 (1 - e-53.4x/92.3)r2 = 0.78, p < 0.001, n = 500
-5 0 5 10 15 20 25 30
% P
icop
hyto
plan
kton
Chl
a
0
20
40
60
80
100
-5 0 5 10 15 20 25 30
% N
anop
hyto
plan
kton
Chl
a
0
20
40
60
80
100
Temperature (°C)
-5 0 5 10 15 20 25 30
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
No relationship between temperature and size-frac. Chl a
Pico Nano
Micro
Temperature (°C)
-5 0 5 10 15 20 25 30 35
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
1817
4
16
10
33
23 30
2019
22
14
9
32
29
26
2
21
15
6
8
3124
13
25
1
3 28
7
27
12
11
5
1. Marguerite Bay, Antarctic Peninsula, winter2. Marguerite Bay, Antarctic Peninsula, summer3. Southern Ocean, Atl. sector, spring ice edge zone4. Southern Ocean, Atl. sector, marginal ice zone 5. Southern Ocean, Atl. sector, polar front 6. SOIREE Fe addition exp. (Southern Ocean), inside7. SOIREE Fe addition exp., outside8. SOFeX iron addition exp. (Southern Ocean), inside 9. SOFeX iron addition exp., outside10. Kerguelen Plateau, Fe-fertilised waters11. Kerguelen Plateau, HNLC water12. SEEDS Fe addition exp. (subarctic W Pacific), inside 13. SEEDS Fe addition exp., outside 14. SERIES iron addition exp. (Gulf of Alaska), inside15. SERIES iron addition exp., outside 16. Okhotsk Sea (western Pacific Ocean), Oct 199317. Okhotsk Sea, Nov 199318. NE subarctic Pacific, late summer 19. NE subarctic Pacific, late winter 20. NE subarctic Pacific, late spring21. NW subarctic Pacific, summer22. NW subarctic Pacific, autumn 23. NW subarctic Pacific, winter 24. Ría de Vigo (NW Iberian peninsula), winter 25. Ría de Vigo, upwelling season26. Gulf of Tehuantepec (SW Mexico), Jan-Feb 1999 27. Gulf of Tehuantepec, Jan-Feb 198928. Johor Strait (Singapore), May-Jul 1998 29. Iskenderun Bay (NE Mediterranean Sea, Jul 2003 30. North & South Atl. subtropical gyres 31. Arabian Sea during the 1995 monsoon (Aug-Sep) 32. IronEx II Fe addition exp., inside 33. IronEx II Fe addition exp., outside
Temperature vs. % microphytoplankton Chl a
Locations
Temperature (°C)
-5 0 5 10 15 20 25 30 35
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
1817
4
16
10
33
23 30
2019
22
14
9
32
29
26
2
21
15
6
8
3124
13
25
1
3 28
7
27
12
11
5
1. Marguerite Bay, Antarctic Peninsula, winter2. Marguerite Bay, Antarctic Peninsula, summer3. Southern Ocean, Atl. sector, spring ice edge zone4. Southern Ocean, Atl. sector, marginal ice zone 5. Southern Ocean, Atl. sector, polar front 6. SOIREE Fe addition exp. (Southern Ocean), inside7. SOIREE Fe addition exp., outside8. SOFeX iron addition exp. (Southern Ocean), inside 9. SOFeX iron addition exp., outside10. Kerguelen Plateau, Fe-fertilised waters11. Kerguelen Plateau, HNLC water12. SEEDS Fe addition exp. (subarctic W Pacific), inside 13. SEEDS Fe addition exp., outside 14. SERIES iron addition exp. (Gulf of Alaska), inside15. SERIES iron addition exp., outside 16. Okhotsk Sea (western Pacific Ocean), Oct 199317. Okhotsk Sea, Nov 199318. NE subarctic Pacific, late summer 19. NE subarctic Pacific, late winter 20. NE subarctic Pacific, late spring21. NW subarctic Pacific, summer22. NW subarctic Pacific, autumn 23. NW subarctic Pacific, winter 24. Ría de Vigo (NW Iberian peninsula), winter 25. Ría de Vigo, upwelling season26. Gulf of Tehuantepec (SW Mexico), Jan-Feb 1999 27. Gulf of Tehuantepec, Jan-Feb 198928. Johor Strait (Singapore), May-Jul 1998 29. Iskenderun Bay (NE Mediterranean Sea, Jul 2003 30. North & South Atl. subtropical gyres 31. Arabian Sea during the 1995 monsoon (Aug-Sep) 32. IronEx II Fe addition exp., inside 33. IronEx II Fe addition exp., outside
Locations
Temperature vs. % microphytoplankton Chl a
Temperature (°C)
-5 0 5 10 15 20 25 30 35
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
1817
4
16
10
33
23 30
2019
22
14
9
32
29
26
2
21
15
6
8
3124
13
25
1
3 28
7
27
12
11
5
1. Marguerite Bay, Antarctic Peninsula, winter2. Marguerite Bay, Antarctic Peninsula, summer3. Southern Ocean, Atl. sector, spring ice edge zone4. Southern Ocean, Atl. sector, marginal ice zone 5. Southern Ocean, Atl. sector, polar front 6. SOIREE Fe addition exp. (Southern Ocean), inside7. SOIREE Fe addition exp., outside8. SOFeX iron addition exp. (Southern Ocean), inside 9. SOFeX iron addition exp., outside10. Kerguelen Plateau, Fe-fertilised waters11. Kerguelen Plateau, HNLC water12. SEEDS Fe addition exp. (subarctic W Pacific), inside 13. SEEDS Fe addition exp., outside 14. SERIES iron addition exp. (Gulf of Alaska), inside15. SERIES iron addition exp., outside 16. Okhotsk Sea (western Pacific Ocean), Oct 199317. Okhotsk Sea, Nov 199318. NE subarctic Pacific, late summer 19. NE subarctic Pacific, late winter 20. NE subarctic Pacific, late spring21. NW subarctic Pacific, summer22. NW subarctic Pacific, autumn 23. NW subarctic Pacific, winter 24. Ría de Vigo (NW Iberian peninsula), winter 25. Ría de Vigo, upwelling season26. Gulf of Tehuantepec (SW Mexico), Jan-Feb 1999 27. Gulf of Tehuantepec, Jan-Feb 198928. Johor Strait (Singapore), May-Jul 1998 29. Iskenderun Bay (NE Mediterranean Sea, Jul 2003 30. North & South Atl. subtropical gyres 31. Arabian Sea during the 1995 monsoon (Aug-Sep) 32. IronEx II Fe addition exp., inside 33. IronEx II Fe addition exp., outside
Locations
Temperature vs. % microphytoplankton Chl a
Temperature (°C)
-5 0 5 10 15 20 25 30 35
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
1817
4
16
10
33
23 30
2019
22
14
9
32
29
26
2
21
15
6
8
3124
13
25
1
3 28
7
27
12
11
5
1. Marguerite Bay, Antarctic Peninsula, winter2. Marguerite Bay, Antarctic Peninsula, summer3. Southern Ocean, Atl. sector, spring ice edge zone4. Southern Ocean, Atl. sector, marginal ice zone 5. Southern Ocean, Atl. sector, polar front 6. SOIREE Fe addition exp. (Southern Ocean), inside7. SOIREE Fe addition exp., outside8. SOFeX iron addition exp. (Southern Ocean), inside 9. SOFeX iron addition exp., outside10. Kerguelen Plateau, Fe-fertilised waters11. Kerguelen Plateau, HNLC water12. SEEDS Fe addition exp. (subarctic W Pacific), inside 13. SEEDS Fe addition exp., outside 14. SERIES iron addition exp. (Gulf of Alaska), inside15. SERIES iron addition exp., outside 16. Okhotsk Sea (western Pacific Ocean), Oct 199317. Okhotsk Sea, Nov 199318. NE subarctic Pacific, late summer 19. NE subarctic Pacific, late winter 20. NE subarctic Pacific, late spring21. NW subarctic Pacific, summer22. NW subarctic Pacific, autumn 23. NW subarctic Pacific, winter 24. Ría de Vigo (NW Iberian peninsula), winter 25. Ría de Vigo, upwelling season26. Gulf of Tehuantepec (SW Mexico), Jan-Feb 1999 27. Gulf of Tehuantepec, Jan-Feb 198928. Johor Strait (Singapore), May-Jul 1998 29. Iskenderun Bay (NE Mediterranean Sea, Jul 2003 30. North & South Atl. subtropical gyres 31. Arabian Sea during the 1995 monsoon (Aug-Sep) 32. IronEx II Fe addition exp., inside 33. IronEx II Fe addition exp., outside
Locations
Temperature vs. % microphytoplankton Chl a
Temperature (°C)
-5 0 5 10 15 20 25 30 35
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
1817
4
16
10
33
23 30
2019
22
14
9
32
29
26
2
21
15
6
8
3124
13
25
1
3 28
7
27
12
11
5
1. Marguerite Bay, Antarctic Peninsula, winter2. Marguerite Bay, Antarctic Peninsula, summer3. Southern Ocean, Atl. sector, spring ice edge zone4. Southern Ocean, Atl. sector, marginal ice zone 5. Southern Ocean, Atl. sector, polar front 6. SOIREE Fe addition exp. (Southern Ocean), inside7. SOIREE Fe addition exp., outside8. SOFeX iron addition exp. (Southern Ocean), inside 9. SOFeX iron addition exp., outside10. Kerguelen Plateau, Fe-fertilised waters11. Kerguelen Plateau, HNLC water12. SEEDS Fe addition exp. (subarctic W Pacific), inside 13. SEEDS Fe addition exp., outside 14. SERIES iron addition exp. (Gulf of Alaska), inside15. SERIES iron addition exp., outside 16. Okhotsk Sea (western Pacific Ocean), Oct 199317. Okhotsk Sea, Nov 199318. NE subarctic Pacific, late summer 19. NE subarctic Pacific, late winter 20. NE subarctic Pacific, late spring21. NW subarctic Pacific, summer22. NW subarctic Pacific, autumn 23. NW subarctic Pacific, winter 24. Ría de Vigo (NW Iberian peninsula), winter 25. Ría de Vigo, upwelling season26. Gulf of Tehuantepec (SW Mexico), Jan-Feb 1999 27. Gulf of Tehuantepec, Jan-Feb 198928. Johor Strait (Singapore), May-Jul 1998 29. Iskenderun Bay (NE Mediterranean Sea, Jul 2003 30. North & South Atl. subtropical gyres 31. Arabian Sea during the 1995 monsoon (Aug-Sep) 32. IronEx II Fe addition exp., inside 33. IronEx II Fe addition exp., outside
Locations
Temperature vs. % microphytoplankton Chl a
Temperature (°C)
-5 0 5 10 15 20 25 30 35
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
1817
4
16
10
33
23 30
2019
22
14
9
32
29
26
2
21
15
6
8
3124
13
25
1
3 28
7
27
12
11
5
1. Marguerite Bay, Antarctic Peninsula, winter2. Marguerite Bay, Antarctic Peninsula, summer3. Southern Ocean, Atl. sector, spring ice edge zone4. Southern Ocean, Atl. sector, marginal ice zone 5. Southern Ocean, Atl. sector, polar front 6. SOIREE Fe addition exp. (Southern Ocean), inside7. SOIREE Fe addition exp., outside8. SOFeX iron addition exp. (Southern Ocean), inside 9. SOFeX iron addition exp., outside10. Kerguelen Plateau, Fe-fertilised waters11. Kerguelen Plateau, HNLC water12. SEEDS Fe addition exp. (subarctic W Pacific), inside 13. SEEDS Fe addition exp., outside 14. SERIES iron addition exp. (Gulf of Alaska), inside15. SERIES iron addition exp., outside 16. Okhotsk Sea (western Pacific Ocean), Oct 199317. Okhotsk Sea, Nov 199318. NE subarctic Pacific, late summer 19. NE subarctic Pacific, late winter 20. NE subarctic Pacific, late spring21. NW subarctic Pacific, summer22. NW subarctic Pacific, autumn 23. NW subarctic Pacific, winter 24. Ría de Vigo (NW Iberian peninsula), winter 25. Ría de Vigo, upwelling season26. Gulf of Tehuantepec (SW Mexico), Jan-Feb 1999 27. Gulf of Tehuantepec, Jan-Feb 198928. Johor Strait (Singapore), May-Jul 1998 29. Iskenderun Bay (NE Mediterranean Sea, Jul 2003 30. North & South Atl. subtropical gyres31. Arabian Sea during the 1995 monsoon (Aug-Sep) 32. IronEx II Fe addition exp., inside 33. IronEx II Fe addition exp., outside
Locations
Temperature vs. % microphytoplankton Chl a
Temperature (°C)
-5 0 5 10 15 20 25 30 35
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
1817
4
16
10
33
23 30
2019
22
14
9
32
29
26
2
21
15
6
8
3124
13
25
1
3 28
7
27
12
11
5
1. Marguerite Bay, Antarctic Peninsula, winter2. Marguerite Bay, Antarctic Peninsula, summer3. Southern Ocean, Atl. sector, spring ice edge zone4. Southern Ocean, Atl. sector, marginal ice zone 5. Southern Ocean, Atl. sector, polar front 6. SOIREE Fe addition exp. (Southern Ocean), inside7. SOIREE Fe addition exp., outside8. SOFeX iron addition exp. (Southern Ocean), inside 9. SOFeX iron addition exp., outside10. Kerguelen Plateau, Fe-fertilised waters11. Kerguelen Plateau, HNLC water12. SEEDS Fe addition exp. (subarctic W Pacific), inside 13. SEEDS Fe addition exp., outside 14. SERIES iron addition exp. (Gulf of Alaska), inside15. SERIES iron addition exp., outside 16. Okhotsk Sea (western Pacific Ocean), Oct 199317. Okhotsk Sea, Nov 199318. NE subarctic Pacific, late summer 19. NE subarctic Pacific, late winter 20. NE subarctic Pacific, late spring21. NW subarctic Pacific, summer22. NW subarctic Pacific, autumn 23. NW subarctic Pacific, winter 24. Ría de Vigo (NW Iberian peninsula), winter 25. Ría de Vigo, upwelling season26. Gulf of Tehuantepec (SW Mexico), Jan-Feb 1999 27. Gulf of Tehuantepec, Jan-Feb 198928. Johor Strait (Singapore), May-Jul 1998 29. Iskenderun Bay (NE Mediterranean Sea, Jul 2003 30. North & South Atl. subtropical gyres 31. Arabian Sea during the 1995 monsoon (Aug-Sep) 32. IronEx II Fe addition exp., inside 33. IronEx II Fe addition exp., outside
Locations
Temperature vs. % microphytoplankton Chl a
% P
icop
hyto
plan
kton
Chl
a
0
20
40
60
80
100
% N
anop
hyto
plan
kton
Chl
a
0
20
40
60
80
100
Total primary production (µg C L-1 d-1)
0 500 1000 1500
% M
icro
phyt
opla
nkto
n C
hl a
0
20
40
60
80
100
0 100 200
020406080
100
% Chl a in each size class strongly dependent on primary productivity, e.g. resource utilization rate
Pico Nano
Micro
coldtemperatewarm
y = 79.5 (1 - e-2.4x/79.5)r2 = 0.59, p < 0.001, n = 165
0 500 1000 1500 0 500 1000 1500
A simple simulation indicates the temperature-size rule can cause only minor changes in size structure
log10 cell size (µm3)
-1 0 1 2 3 4 5
log 10
cel
l abu
ndan
ce (c
ell m
L-1)
0
1
2
3
4
5
pico micronano
2 µm
20 µ
m
control
+20°C, -50% cell size+10°C, -25% cell size
2.6 63.434.03.0 60.636.43.7 54.441.8
Biovolume(%)
TemperatureR
esou
rce
utili
zatio
n ra
te
HIG
HLO
W
COLD WARMTEMPERATE
A summary of phytoplankton size structure in the ocean
Small cells dominate
Large cells dominate
• Summer bloom in Antarctic Peninsula
• NW Iberian coast, upwelling season
• Subtropical gyres (macronutrient limitation)
• Fertilised patch, Fe addition expts in Southern Ocean
• Eq. Pac., HNLC waters (Fe limitation)
• Fertilised patch, SERIES experiment (Gulf of Alaska)
• NW Iberian coast, winter (light limitation)
• Coastal, nutrient-rich waters in warm seas
• Fertilised patch, IronEx II (Eq. Pacific)
• Eastern subarctic N Pacific (Fe limitation)
• Antarctic peninsula in winter (light limitation)
• Southern Ocean HNLC waters in summer (Fe limitation)
Conclusions
• Phytoplankton size structure controlled by rate of resource utilization
• Role of temperature per se is negligible
• No universal effect of warming on phytoplankton size structure
Acknowledgements
Thanks to P. W. Boyd, A. Clarke, and A. Tsuda for making their data available.
Research funded by the Spanish Ministry of Science and Innovation.
A research project funded by Ministerio de Ciencia e Innovación
(CTM2008-03999)
P E R S E OP E R S E OMacroecological patterns in marine phytoplankton