88
high evaporation, and a low freshwater supply, probably because of plant physiological responses to high salinity. Cintrón et al. (1978) developed the following equation for the effect of salinity on mangrove tree height in Puerto Rico:
Tree height m
S oil salinity ppt
( ) = -
( )+
=
(
)
0 20
1 6 58
072
2
.
.
.
r
(3.4)
Other factors such as soil nutrients and flooding conditions can also influence plant
morphology and biomass amount. Donato et al. (2011) measured mangrove biomass in 25 forests in the Indo-West Pacific region and compared the data between
oceanic mangroves, situated in marine-edge settings, often on the coasts of islands
with fringing coral reefs, and estuarine mangroves, situated on large alluvial deltas,
often within a protected lagoon. They found that the area-based aboveground biomass carbon of oceanic mangroves was higher than that of estuarine mangroves,
and attributed this difference to differences in nutrient and physical conditions
between the settings. They also reported that the area-based aboveground biomass
tended to increase with distance inland from the coast, particularly so in estuarine
settings.
The biomass of the belowground parts, here including aerial root systems, has
been estimated to be large in some mangrove forests in Indonesia: 196.1 t ha
−1
in a
Rhizophora apiculata stand and 180.7 t ha
−1
in a Bruguiera gymnorrhiza stand
(Komiyama et al. 1988). These estimates are higher than belowground estimates for
most upland forests (<150 t ha
−1
) (Cairns et al. 1997). Most upland forest trees partition <30% of their biomass to belowground parts (Ulrich et al. 1974), whereas mangrove trees may partition 40–60% of the total to belowground biomass (Saenger
1982; Lugo 1990). Several explanations have been proposed for the high percentage
of root mass of mangroves. Komiyama et al. (1988) suggested that a high belowground biomass may be needed to physically support the plant body in unstable
muds. But the belowground biomass of mangroves is not invariably high: for example, Gong and Ong (1990) reported that in mangroves in Malaysia, it represents
Table 3.6 Aboveground
biomass (AGB) of mangroves
(dry weight) predicted by the
model equation of Hutchison
et al. (2014)
Region
AGB (10
6 t)
Mean AGB
(t ha
−1 )
East and south Africa
143.33
136.4
Middle East
14.75
110.4
South Asia
136.60
136.4
Southeast Asia
1131.56
230.9
East Asia
2.54
107.2
Australia and New Zealand
87.51
132.9
Pacific Islands
133.47
233.3
North and Central America
and the Caribbean
356.29
145.3
South America
465.91
185.7
West and Central Africa
357.44
177.8
Global Total
2829.39
184.8
T. Inoue
high evaporation, and a low freshwater supply, probably because of plant physiological responses to high salinity. Cintrón et al. (1978) developed the following equation for the effect of salinity on mangrove tree height in Puerto Rico:
Tree height m
S oil salinity ppt
( ) = -
( )+
=
(
)
0 20
1 6 58
072
2
.
.
.
r
(3.4)
Other factors such as soil nutrients and flooding conditions can also influence plant
morphology and biomass amount. Donato et al. (2011) measured mangrove biomass in 25 forests in the Indo-West Pacific region and compared the data between
oceanic mangroves, situated in marine-edge settings, often on the coasts of islands
with fringing coral reefs, and estuarine mangroves, situated on large alluvial deltas,
often within a protected lagoon. They found that the area-based aboveground biomass carbon of oceanic mangroves was higher than that of estuarine mangroves,
and attributed this difference to differences in nutrient and physical conditions
between the settings. They also reported that the area-based aboveground biomass
tended to increase with distance inland from the coast, particularly so in estuarine
settings.
The biomass of the belowground parts, here including aerial root systems, has
been estimated to be large in some mangrove forests in Indonesia: 196.1 t ha
−1
in a
Rhizophora apiculata stand and 180.7 t ha
−1
in a Bruguiera gymnorrhiza stand
(Komiyama et al. 1988). These estimates are higher than belowground estimates for
most upland forests (<150 t ha
−1
) (Cairns et al. 1997). Most upland forest trees partition <30% of their biomass to belowground parts (Ulrich et al. 1974), whereas mangrove trees may partition 40–60% of the total to belowground biomass (Saenger
1982; Lugo 1990). Several explanations have been proposed for the high percentage
of root mass of mangroves. Komiyama et al. (1988) suggested that a high belowground biomass may be needed to physically support the plant body in unstable
muds. But the belowground biomass of mangroves is not invariably high: for example, Gong and Ong (1990) reported that in mangroves in Malaysia, it represents
Table 3.6 Aboveground
biomass (AGB) of mangroves
(dry weight) predicted by the
model equation of Hutchison
et al. (2014)
Region
AGB (10
6 t)
Mean AGB
(t ha
−1 )
East and south Africa
143.33
136.4
Middle East
14.75
110.4
South Asia
136.60
136.4
Southeast Asia
1131.56
230.9
East Asia
2.54
107.2
Australia and New Zealand
87.51
132.9
Pacific Islands
133.47
233.3
North and Central America
and the Caribbean
356.29
145.3
South America
465.91
185.7
West and Central Africa
357.44
177.8
Global Total
2829.39
184.8
T. Inoue