Picoplankton Community Structure
subarctic (K2) v.s.
subtropical (Aloha similar)
----------------------------------------------
Nianzhi (George) Jiao, Yao Zhang
Xiamen University
China
Investigation Sites
Fig. 1 Sampling stations Chlorophyll a remote images (Aqua-MODIS) of August 2005 were employed as the backgrounds. NWPG: North Western Pacific; NEP: North Eastern Pacific; MNEP: Marginal sea of North Eastern Pacific.
0.01
0.10
1.00
10.0
60.0
mg
m- 3
0
20
40
60
80
K2
NW PG1
NEP1
ALOHA
NEP2 NEP3
160W 140W 120W 100W160E140E120E 180
NW PG2
Picoplankton discrimination by FCM
Prochlorococcus Synechococcus
Picoeukaryotes Heterotrophic bacteria
AAPB (AAPB (aerobic anoxygenic phototrophic bacteriaaerobic anoxygenic phototrophic bacteria))
TIREM TIREM Jiao et al., 2006,Jiao et al., 2006, Journal of Microbiological Methods
Exposure time (min)
0 3 6 9 12 15 18
Cou
nts
/ M
icro
-fie
ld
20
40
60
80
200
Cyano CountDAPI CountIR Count
Paths of Photosynthesis
Karl, 2002
Sunlight
Phtosynthesis in Phytoplankton
Phtosynthesisin AAPB
C fixation
ATP
Save OC Ocean C cycling
Re-budget ??
respiration consumption
Carbon cycling
TEM-Ultrathin sections
SEM
dc10-s
dg26-y-1(2216)
dc10-s
dc10-s
db6-y-2(0.2)
TEM-Negatively stained cells
AAPB cells
Non-AAPB
AAPB
ciliates Meso-zooplanktonflagellates
ciliates
flagellates
Meso-zooplankton
Cellular contribution to sinking flux in AAPB could also be higher than non-AAPB
Deployment 1 Deployment 2 Cell Abundance (cells/ml)
1e+3 1e+4 1e+5 1e+6
De
pth
(m
)
0
10
20
30
40
50
Euk.Syn.Bact.AAPB
Cell Abundance (cells/ml)
1e+3 1e+4 1e+5 1e+60
10
20
30
40
50
Depth profiles of the abundance (upper)And biomass (lower) of picoplankton at K2.
Cell Abundance (cells/ml)
1e+1 1e+2 1e+3 1e+4 1e+5 1e+6
Dep
th (
m)
0
50
100
150
200
Euk.Syn.Bact.AAPB
Cell Abundance (cells/ml)
1e+1 1e+2 1e+3 1e+4 1e+5 1e+60
50
100
150
200
K2Deployment 1
K2Deployment 2
Fig. 4 Depth profiles of picoplankton at K2 with false connection down to 200m.
The data of 60-200m are adopted from Liu et al. 2002.
Picoplankton Carbon Biomass at K2
0 5 10 15 20 25 30
K2Deployment 1
Biomass (C mg/m3)
051015202530
Dep
th (
m)
0
10
20
30
40
50
0 5 10 15 20 25 30
non-AAPBAAPB
K2Deployment 2
Biomass (C mg/m3)
0510152025300
10
20
30
40
50
Euk. Syn.
0 5 10 15 20 25 30
K2Deployment 1
051015202530
Dep
th (
m)
0
50
100
150
200
0 5 10 15 20 25 30
non-AAPBAAPB
K2Deployment 2
0510152025300
50
100
150
200
Euk. Syn.
Fig. 5 Depth profiles of pico-sized autotrophic and heterotrophic carbon biomass at K2. The data of 60-200m (shaded) were from Liu et al. 2002.
Comparison between K2 and Aloha similars
Fig. 1 Sampling stations Chlorophyll a remote images (Aqua-MODIS) of August 2005 were employed as the backgrounds. NWPG: North Western Pacific; NEP: North Eastern Pacific; MNEP: Marginal sea of North Eastern Pacific.
0.01
0.10
1.00
10.0
60.0
mg
m- 3
0
20
40
60
80
K2
NW PG1
NEP1
ALOHA
NEP2 NEP3
160W 140W 120W 100W160E140E120E 180
NW PG2
Pico- biomass K2 v.s. NWPG
Fig. 6 Vertical distribution of pico-sized autotrophic and heterotrophic carbon biomass
at K2 and NWPG1
0 5 10 15 20 25 30
K2
Biomass (C mg/m3)
051015202530
Dep
th (
m)
0
50
100
150
200
0 5 10 15 20 25 30
non-AAPBAAPB
NWPG1
Biomass (C mg/m3)
0510152025300
50
100
150
200
Pro.Euk.Syn.
Surface layer: Auto > hetero Auto < heteroTwilight zone: Auto < hetero Auto > hetero
GyreK2
Comparison along longitude
Fig. 1 Sampling stations Chlorophyll a remote images (Aqua-MODIS) of August 2005 were employed as the backgrounds. NWPG: North Western Pacific; NEP: North Eastern Pacific; MNEP: Marginal sea of North Eastern Pacific.
0.01
0.10
1.00
10.0
60.0
mg
m- 3
0
20
40
60
80
K2
NW PG1
NEP1
ALOHA
NEP2 NEP3
160W 140W 120W 100W160E140E120E 180
NW PG2
NEP1, 2 ,3,4Auto –fraction
increased eastward
Vertical distibution of pico-sized autotrophic and heterotrophic carbon biomas
s at NEP
0 5 10 15 20 25
NEP3
0510152025
Depth
(m
)
0
50
100
150
200
0 5 10 15 20 25
NEP2
0510152025
Depth
(m
)
0
50
100
150
200
0 5 10 15 20 25
non-AAPBAAPB
NEP1
Biomass (C mg/m3)
0510152025
Depth
(m
)
0
50
100
150
200
Pro.Euk.Syn.
Fig. 10 Variation of vertical profiles of pico-sized autotrophic and heterotrophic carbon biomass along longit
ude
0 10 20 30 40 50 60
non-AAPB AAPB
NEP4Deployment 1
Biomass (C mg/m3)
0102030405060
De
pth
(m
)
0
50
100
150
200
Pro.Euk.Syn.
0 10 20 30 40 50 60
NEP4Deployment 2
Biomass (C mg/m3)
01020304050600
50
100
150
200
0 10 20 30 40 50 60
NEP4Deployment 3
0102030405060
De
pth
(m
)
0
50
100
150
200
0 10 20 30 40 50 60
NEP4Deployment 4
01020304050600
50
100
150
200
0 10 20 30 40 50 60
NEP
01020304050600
50
100
150
200
0 10 20 30 40 50 60
NEP2
0102030405060
De
pth
(m
)
0
50
100
150
200
0 10 20 30 40 50 60
NEP1
01020304050600
50
100
150
200
0 10 20 30 40 50 60
NWPG2
0102030405060
De
pth
(m
)
0
50
100
150
200
0 10 20 30 40 50 60
NWPG1
01020304050600
50
100
150
200
NEP4 (1,2,3,4) <=> K2 (1,2) in terms of Biomass flux and auto/hetero ratio; although composition are different
0 10 20 30 40 50 60
non-AAPB AAPB
MNEPDeployment 1
Biomass (C mg/m3)
0102030405060
Dep
th (
m)
0
50
100
150
200
Pro.Euk.Pro.
0 10 20 30 40 50 60
MNEPDeployment 2
Biomass (C mg/m3)
01020304050600
50
100
150
200
0 10 20 30 40 50 60
MNEPDeployment 3
0102030405060
Dep
th (
m)
0
50
100
150
200
0 10 20 30 40 50 60
MNEPDeployment 4
01020304050600
50
100
150
200
Vertical distribution of pico-sized autotrophic and heterotro
phic carbon biomass at NEP4
Depth profiles ofpico-sized autotrophic and heterotrophic carbon biomass
at K2
Two dimensional trends
0.01
0.10
1.00
10.0
60.0
mg
m- 3
0
20
40
60
80
K2
NEP3
120W 100W160E140E120E
NW PG2Along trophic gradient
Alo
ng
la
titu
de
180 160W 140W
Conclusions• Picoeukaryoes and Synechococcus dominate carbon biomass of
pico-autotrophs at K2 • Prochlorococcus dominate carbon biomass of pico-autotrophs at l
ow latitudes especially in the oligotrophic areas. • AAPB are more abundant in entrophic waters than in oligotrphic w
aters
• picoplankton carbon flux maximum layer depth eutrophic waters: 50-75m oligotrophic waters: 100-150m
• Temperature and nutrients are two major controlling factors
• Variations along gradients: autotrophs >> heterotrophic bacteria • Therefore whether or not a province is autotrophic or heterotrophi
c is determined primarily by autotrophs
Cheers!
K2 Aloha