16
flats and estuaries, which are ecotones between the land and ocean. Chapter 11
(Kuwae et al. 2018) also discusses the fact that phytoplankton in estuaries and
within bays can contributes to carbon storage.
1.3 Characteristics of Sequestration and Storage in Blue
Carbon Ecosystems
In this section, the mechanism by which blue carbon ecosystems sequester and store
blue carbon is discussed. To understand how blue carbon ecosystems sequester and
store blue carbon, it is essential to understand the function of each ecosystem and its
biological characteristics. We first describe the general biological characteristics of
blue carbon ecosystems and also biogeographic features. The species that support
the base of the ecosystem and that determine the biological and physicochemical
characteristics of the ecosystem have been termed foundation species (Ellison et al.
2005). Blue carbon ecosystems have characteristic foundation species. They therefore provide characteristic ecosystem services, not just blue carbon sequestration
and storage.
1.3.1 Saltmarshes on Tidal Flats
Saltmarshes form in the upper coastal intertidal zone, which is regularly flooded by
seawater during high tides. The vegetation consists of dense stands of salt-tolerant
plants including herbs, grasses, and short shrubs (Adams 1990, Woodroffe 2002).
The dense vegetation exhibits extremely high primary production and also provides
coastal protection by trapping and binding sediments (Woodroffe 2002, Chap. 8).
Saltmarshes, along with seagrass ecosystems and mangrove forests, are sites of
effective organic carbon sequestration and storage. These three ecosystems have
recently been called blue carbon ecosystems, but they were originally recognized as
ecosystems supporting diverse communities that include terrestrial organisms such
as angiosperms, insects, birds, and mammals as well as marine organisms such as
algae, molluscs, crustaceans, and fish (Pennings and Bertness 2001).
Saltmarshes are commonly found on shorelines that consist of muddy or sandy
tidal flats with sluggish tidal movement and low wave action at almost all latitudes,
but they are largely replaced by mangrove forests in the subtropics and tropics.
(Pennings and Bertness 2001). Saltmarshes are therefore located primarily in temperate and higher latitudes (Fig. 1.3a). On the latest global map of saltmarshes by
Mcowen et al. (2017), the global coverage of saltmarshes is estimated to be about
5.5 × 10
6
ha.
M. Hori et al.
flats and estuaries, which are ecotones between the land and ocean. Chapter 11
(Kuwae et al. 2018) also discusses the fact that phytoplankton in estuaries and
within bays can contributes to carbon storage.
1.3 Characteristics of Sequestration and Storage in Blue
Carbon Ecosystems
In this section, the mechanism by which blue carbon ecosystems sequester and store
blue carbon is discussed. To understand how blue carbon ecosystems sequester and
store blue carbon, it is essential to understand the function of each ecosystem and its
biological characteristics. We first describe the general biological characteristics of
blue carbon ecosystems and also biogeographic features. The species that support
the base of the ecosystem and that determine the biological and physicochemical
characteristics of the ecosystem have been termed foundation species (Ellison et al.
2005). Blue carbon ecosystems have characteristic foundation species. They therefore provide characteristic ecosystem services, not just blue carbon sequestration
and storage.
1.3.1 Saltmarshes on Tidal Flats
Saltmarshes form in the upper coastal intertidal zone, which is regularly flooded by
seawater during high tides. The vegetation consists of dense stands of salt-tolerant
plants including herbs, grasses, and short shrubs (Adams 1990, Woodroffe 2002).
The dense vegetation exhibits extremely high primary production and also provides
coastal protection by trapping and binding sediments (Woodroffe 2002, Chap. 8).
Saltmarshes, along with seagrass ecosystems and mangrove forests, are sites of
effective organic carbon sequestration and storage. These three ecosystems have
recently been called blue carbon ecosystems, but they were originally recognized as
ecosystems supporting diverse communities that include terrestrial organisms such
as angiosperms, insects, birds, and mammals as well as marine organisms such as
algae, molluscs, crustaceans, and fish (Pennings and Bertness 2001).
Saltmarshes are commonly found on shorelines that consist of muddy or sandy
tidal flats with sluggish tidal movement and low wave action at almost all latitudes,
but they are largely replaced by mangrove forests in the subtropics and tropics.
(Pennings and Bertness 2001). Saltmarshes are therefore located primarily in temperate and higher latitudes (Fig. 1.3a). On the latest global map of saltmarshes by
Mcowen et al. (2017), the global coverage of saltmarshes is estimated to be about
5.5 × 10
6
ha.
M. Hori et al.