60
regarding OC burial in seagrass meadows rely on sedimentation rates measured
using the
14
C method (Table 2.6). It should be noted that these data generally do not
represent instantaneous rates, but rather average rates over the previous hundreds of
years.
Quite a few studies have evaluated the sedimentation rate in seagrass meadows
(Table 2.6). Most of these studies (except Jankowska et al. 2016) used
14
C dating,
and the measured sedimentation rates generally ranged from 0.3 to 1.4 mm year
−1
,
except in meadows of the large Mediterranean seagrass species P. oceanica (average,
2.1 mm year
−1
). The OC sequestration rate is even more variable among different
seagrass species, with that in P. oceanica meadows (average, 5820 mmol C
m
−2
year
−1
) being an order of magnitude greater than that in seagrass meadows of
other species (420 mmol C m
−2
year
−1
). This is due to both higher sedimentation
rates and greater OC concentrations in the sediment of P. oceanica meadows than in
other meadows. It is very difficult to estimate the contribution of OC sequestration
in seagrass meadows to the global carbon budget, because the available information
is still far from sufficient for evaluating geographic variability in the sedimentation
and OC sequestration rates in seagrass meadows (see also Sect. 2.8). With this in
Table 2.6 Examples of sedimentation rates and OC sequestration rate measured for seagrass
meadow sediments
Geographic
region
Latitude
Dominant
seagrass
n
Sedimentation
rate (mm year
–1 )
OC sequestration
rate (mmol C
m
–2 year
–1 )
References
Baltic Sea
54.23°–
54.42°N
Zostera
marina
3 1.3
210 ± 130
Jankowska
et al. (2016)
Northern Japan 43.33°N Zostera
marina
3 0.37 ± 0.18
458 ± 156
Tokoro et al.
(2014)
Southeastern
Spain
38.16°–
42.30°N
Posidonia
oceanica
7 1.75 ± 1.18
4800 ± 3500
Mateo et al.
(1997)
Northwestern
Mediterranean
38.72°–
38.91°N
Posidonia
oceanica
2 2.4 – 4.2
7100 – 11700
Serrano
et al. (2014)
Central Japan
33.60°–
34.32°N
Zostera
marina
3 0.37 – 1.34
570 ± 290
Miyajima
et al. (2015)
Southwestern
Japan
24.49°N Enhalus
acoroides
1 1.23
447
Miyajima
et al. (2015)
Southern
Thailand
7.39°N
Thalassia
hemprichii
1 0.82
203
Miyajima
et al. (2015)
Western
Australia
32.16°S Posidonia
sinuosa
4 0.6 – 1.3
530 ± 430
Serrano
et al. (2014)
Southwestern
Australia
34.98°S Posidonia
australis
1 0.49
287
Rozaimi
et al. (2016)
Average
25
2450 ± 3450
Average excluding Posidonia oceanica
meadows
16
420 ± 270
T. Miyajima and M. Hamaguchi
regarding OC burial in seagrass meadows rely on sedimentation rates measured
using the
14
C method (Table 2.6). It should be noted that these data generally do not
represent instantaneous rates, but rather average rates over the previous hundreds of
years.
Quite a few studies have evaluated the sedimentation rate in seagrass meadows
(Table 2.6). Most of these studies (except Jankowska et al. 2016) used
14
C dating,
and the measured sedimentation rates generally ranged from 0.3 to 1.4 mm year
−1
,
except in meadows of the large Mediterranean seagrass species P. oceanica (average,
2.1 mm year
−1
). The OC sequestration rate is even more variable among different
seagrass species, with that in P. oceanica meadows (average, 5820 mmol C
m
−2
year
−1
) being an order of magnitude greater than that in seagrass meadows of
other species (420 mmol C m
−2
year
−1
). This is due to both higher sedimentation
rates and greater OC concentrations in the sediment of P. oceanica meadows than in
other meadows. It is very difficult to estimate the contribution of OC sequestration
in seagrass meadows to the global carbon budget, because the available information
is still far from sufficient for evaluating geographic variability in the sedimentation
and OC sequestration rates in seagrass meadows (see also Sect. 2.8). With this in
Table 2.6 Examples of sedimentation rates and OC sequestration rate measured for seagrass
meadow sediments
Geographic
region
Latitude
Dominant
seagrass
n
Sedimentation
rate (mm year
–1 )
OC sequestration
rate (mmol C
m
–2 year
–1 )
References
Baltic Sea
54.23°–
54.42°N
Zostera
marina
3 1.3
210 ± 130
Jankowska
et al. (2016)
Northern Japan 43.33°N Zostera
marina
3 0.37 ± 0.18
458 ± 156
Tokoro et al.
(2014)
Southeastern
Spain
38.16°–
42.30°N
Posidonia
oceanica
7 1.75 ± 1.18
4800 ± 3500
Mateo et al.
(1997)
Northwestern
Mediterranean
38.72°–
38.91°N
Posidonia
oceanica
2 2.4 – 4.2
7100 – 11700
Serrano
et al. (2014)
Central Japan
33.60°–
34.32°N
Zostera
marina
3 0.37 – 1.34
570 ± 290
Miyajima
et al. (2015)
Southwestern
Japan
24.49°N Enhalus
acoroides
1 1.23
447
Miyajima
et al. (2015)
Southern
Thailand
7.39°N
Thalassia
hemprichii
1 0.82
203
Miyajima
et al. (2015)
Western
Australia
32.16°S Posidonia
sinuosa
4 0.6 – 1.3
530 ± 430
Serrano
et al. (2014)
Southwestern
Australia
34.98°S Posidonia
australis
1 0.49
287
Rozaimi
et al. (2016)
Average
25
2450 ± 3450
Average excluding Posidonia oceanica
meadows
16
420 ± 270
T. Miyajima and M. Hamaguchi