11
(4) Maintain food and livelihood safety of the marine ecosystem by conducting
comprehensive and integrated ecosystem management to improve resilience to
environmental change by both human societies and nature.
(5) Implement the following mitigation measures to create a win–win situation
with respect to ocean resources;
Improve the efficiency of energy used in marine transportation, fisheries, and
aquaculture, and in marine leisure and tourism.
Encourage sustainable and environmentally friendly harvesting of marine food
resources, such as seaweed farming.
Lessen activities that negatively impact the carbon absorption capacity of the
ocean.
When promoting business, contracting, or coastal development, prioritize the
restoration and protection of coastal macrophytes, which provides not only seafood
and income, but also carbon sequestration and storage.
Manage coastal ecosystems to increase and expand the distribution of seagrass
beds, mangrove forests, and saltmarshes. Transform coastal development so as to
rehabilitate coastal macrophytes as natural capital.
1.2.3 Present Status of Blue Carbon Ecosystems
In the UNEP report, mangrove forests, saltmarshes, and seagrass beds are all called
blue carbon sinks, and they are most important in the sequestering and storing of
ocean CO 2 . These carbon sinks not only make a large contribution to the sequestration and storage of CO 2 , but they also provide a variety of important ecological
services, such as food and livelihood safety to human beings. From this standpoint,
the blue carbon ecosystem is comparable to a rainforest in the terrestrial realm. In
this section, we describe the characteristics of a blue carbon ecosystem, and we
explain how and why it sequesters and effectively stores carbon.
In accord with the logic of the UNEP report, the morphological and structural
arrangement of vegetation can be mentioned as a feature common to mangrove
forests, saltmarshes, and seagrass beds. Saltmarshes and seagrass beds are formed
by herbaceous plants, which are known to have a high shoot density and high growth
rate (Pennings and Bertness 2001, Williams and Heck 2001). First, this dense vegetation creates a three-dimensional structure in the sea, provides a habitat for various marine organisms, and restricts the flow of seawater. Second, the vegetation
grows in soft sediments, which are essential for carbon storage. In all mangrove
forests, saltmarshes, and seagrass beds, dense vegetation restricts the flow of seawater and traps organic carbon drifting in the water column. The trapped organic carbon then accumulates in the sediment, where it is stored on site on time scales of
centuries or more. There is a misconception that organic carbon is consumed and
rapidly decomposed in extremely shallow coastal areas because of the high rates of
biological processes, but the amount of organic carbon stored in these systems is
1 Blue Carbon: Characteristics of the Ocean’s Sequestration and Storage Ability…
(4) Maintain food and livelihood safety of the marine ecosystem by conducting
comprehensive and integrated ecosystem management to improve resilience to
environmental change by both human societies and nature.
(5) Implement the following mitigation measures to create a win–win situation
with respect to ocean resources;
Improve the efficiency of energy used in marine transportation, fisheries, and
aquaculture, and in marine leisure and tourism.
Encourage sustainable and environmentally friendly harvesting of marine food
resources, such as seaweed farming.
Lessen activities that negatively impact the carbon absorption capacity of the
ocean.
When promoting business, contracting, or coastal development, prioritize the
restoration and protection of coastal macrophytes, which provides not only seafood
and income, but also carbon sequestration and storage.
Manage coastal ecosystems to increase and expand the distribution of seagrass
beds, mangrove forests, and saltmarshes. Transform coastal development so as to
rehabilitate coastal macrophytes as natural capital.
1.2.3 Present Status of Blue Carbon Ecosystems
In the UNEP report, mangrove forests, saltmarshes, and seagrass beds are all called
blue carbon sinks, and they are most important in the sequestering and storing of
ocean CO 2 . These carbon sinks not only make a large contribution to the sequestration and storage of CO 2 , but they also provide a variety of important ecological
services, such as food and livelihood safety to human beings. From this standpoint,
the blue carbon ecosystem is comparable to a rainforest in the terrestrial realm. In
this section, we describe the characteristics of a blue carbon ecosystem, and we
explain how and why it sequesters and effectively stores carbon.
In accord with the logic of the UNEP report, the morphological and structural
arrangement of vegetation can be mentioned as a feature common to mangrove
forests, saltmarshes, and seagrass beds. Saltmarshes and seagrass beds are formed
by herbaceous plants, which are known to have a high shoot density and high growth
rate (Pennings and Bertness 2001, Williams and Heck 2001). First, this dense vegetation creates a three-dimensional structure in the sea, provides a habitat for various marine organisms, and restricts the flow of seawater. Second, the vegetation
grows in soft sediments, which are essential for carbon storage. In all mangrove
forests, saltmarshes, and seagrass beds, dense vegetation restricts the flow of seawater and traps organic carbon drifting in the water column. The trapped organic carbon then accumulates in the sediment, where it is stored on site on time scales of
centuries or more. There is a misconception that organic carbon is consumed and
rapidly decomposed in extremely shallow coastal areas because of the high rates of
biological processes, but the amount of organic carbon stored in these systems is
1 Blue Carbon: Characteristics of the Ocean’s Sequestration and Storage Ability…