Blue Carbon in Floral Community - Blue Carbon Reservoir of the Blue Planet - page 115

mangroves, seagrasses, salt marshes and other
marine living organisms, which are also known
more speci

of mangrove biomass and productivity is rather
dif

cult due to muddy soil conditions and the
heavy weight of the wood. The peculiar tree form
of mangroves, especially their unusual roots, has
long attracted the attention of botanists and
ecologists (Tomlinson 1986 ). The survival of
mangroves in soft muddy substratum is basically
because of the support of their root system. To
maintain a bottom-heavy tree form (Ong et al.
2004 ) or a low ratio of top biomass to root bio-
mass (T/R ratio; Komiyama et al. 2000 ), man-
groves might allocate a great deal of biomass to
their roots. This phenomenon may produce
peculiar conditions for ecosystem processes in
root zones, owing to the anaerobic conditions.
Over the years, forest ecologists have devel-
oped various methods to estimate the biomass of
forests. Three important methods are usually
adopted for estimating forest biomass: the har-
vest method, the mean-tree method and the
allometric method. In a mature mangrove forest,
the total weight of an individual tree often
reaches several tons (Komiyama et al. 2005 ).
Therefore, the harvest method cannot be easily
used in mature forests and in itself is not repro-
ducible because all trees must be destructively
harvested. The mean-tree method is utilized only
in forests with a homogeneous tree size distri-
bution,

. Mangroves,
salt marshes and seagrasses form much of the
Earth

cally as ' blue carbon '

s blue carbon sinks ( http://www.recoftc.
org/site/resources/Mangroves-more-Carbon-Rich-
and-Important-for-Climate-Change.php ).

'

4.1 Mangroves

Mangrove ecosystems are concentrated along
tropical and subtropical coasts and are the only
known woody halophytes. A part of their pro-
ductivity

ows into adjacent ecosystems, or
conversely, they receive organic materials from
estuarine or oceanic ecosystems (Fig. 4.3 ) (Ong
1993 ; Kristensen et al. 2008 ).
The biological and ecological aspects of
mangroves have been studied worldwide (Lugo
and Snedaker 1974 ; Boto and Wellington 1984 ;
Hutchings and Saenger 1985 ; Twilley et al.
1986 ; Odum and Mclvor 1990 ; Twilley 1995 ;
Cox and Allen 1999 ). Most researchers deal with
patterns of primary productivity, nutrient cycle
and detrital export in riverine mangroves,
whereas fringe and scrub mangrove have been
studied to a lesser extent (Twilley et al. 1992 ;
Alongi et al. 1992 ; Lee 1995 ). The

fl

eld survey such as plantations. The allometric

Fig. 4.3 Mangrove forests supply nutrients to the adjacent estuarine water