377
was particularly popular in the 1990s, aggravated
soil runoff, causing sea bottoms in estuarine
regions and coastal zones to be covered with fi ne
sediment. They concluded that only 2 % of sediment particles that fl ow into estuarine regions are
transported to the outer seas, with the majority
remaining within the bay and contributing continuously to the accumulation of sediment. The
amount of sediment accumulated was estimated
to reach 20,000 tons in a year.
Golbuu et al. ( 2011 ) researched the sedimentation processes of fi ne particles and turbidity
dynamics of watersheds in four terrestrial areas
under differing degrees of development on
Babeldaob Island. It was found that fi ne particle
sedimentation per 1 km
2 ranged between 29.7 and
216 tons annually, with areas under higher levels
of development exhibiting more sedimentation.
For coral reefs, an example illustrating the
link between terrestrial areas and coastal zones is
the death of corals caused by sediment particle
outfl ow. Some studies have also reported that
sediment particle outfl ow has an effect on coral
reef organisms in the Republic of Palau (Fabricius
et al. 2007 ). During periods when the effects of
sediment outfl ow on coral reefs were observed,
the quantity of accumulated microscopic particles was found to be 39.6 mg/cm
2 /day, and the
extent of the sediment’s effects on coral reefs was
reported to depend on the type and species of
organism.
This network via biogeochemical cycle
between mangroves and coral reefs should be
considered in the discussion of coastal management in Palau.
3.2
Environmental Functions
• Environmental purifi cation functions
Mangroves and tidal fl ats are home to immense
numbers of crabs and snails. When these animals
feed, they reduce the amount of organic materials
in tidal fl ats through their ability to purify their
own habitats.
• Refuges for young coral reef fi sh
During high tides, it is possible to observe
small fi sh swimming in from the sea to forage
among the roots of mangroves. Mangroves are an
especially important source of shelter for young
juveniles that live on coral reefs.
• Provision of habitats to birds, insects, and
other animal species
During low tides, a variety of bird species rest
and carry out feeding activities on the tidal fl ats
that extend from mangrove forests. Additionally,
birds deposit organic matter taken from other
tidal fl ats in the form of droppings. Such biological processes cannot be ignored when large populations of bird species are present.
The diverse types of birds inhabiting tidal fl ats
are also of interest to bird-watchers. The use of
tidal fl ats by birds is not random; some bird species use shorelines and water edges, and others
feed with their feet slightly in the water. Although
tidal fl ats may seem uniform, they should be
understood as a collection of many different environments that are utilized by various types of living organisms.
• Opportunities for food resources
To humans, the most important species in
Palau mangrove ecosystems is the mangrove
crab, and attempts at crab breeding are currently
in progress. Land crabs Cardisoma spp. are also
eaten frequently.
Although some mangrove species, such as
mangrove crabs, have been used as food for people in Palau, it is diffi cult to obtain fi sh-catch statistical data for mangrove areas. This is also true
for information on coral reef fi sh, although data
spanning a 5-year period starting in 2002 have
been made public (2006 Statistical Yearbook,
Republic of Palau, Bureau of Budget and
Planning, Ministry of Finance).
3.3
Socioeconomic
Considerations
• Important resources for environmental
education
Because mangroves have been widely used in
a variety of academic researches, fascinating
discoveries have been made, bearing possibilities
for new academic progress and improvements to
human life. Such information can be used for
Mangrove Forest Ecosystem Services with Reference to the Transportation…
was particularly popular in the 1990s, aggravated
soil runoff, causing sea bottoms in estuarine
regions and coastal zones to be covered with fi ne
sediment. They concluded that only 2 % of sediment particles that fl ow into estuarine regions are
transported to the outer seas, with the majority
remaining within the bay and contributing continuously to the accumulation of sediment. The
amount of sediment accumulated was estimated
to reach 20,000 tons in a year.
Golbuu et al. ( 2011 ) researched the sedimentation processes of fi ne particles and turbidity
dynamics of watersheds in four terrestrial areas
under differing degrees of development on
Babeldaob Island. It was found that fi ne particle
sedimentation per 1 km
2 ranged between 29.7 and
216 tons annually, with areas under higher levels
of development exhibiting more sedimentation.
For coral reefs, an example illustrating the
link between terrestrial areas and coastal zones is
the death of corals caused by sediment particle
outfl ow. Some studies have also reported that
sediment particle outfl ow has an effect on coral
reef organisms in the Republic of Palau (Fabricius
et al. 2007 ). During periods when the effects of
sediment outfl ow on coral reefs were observed,
the quantity of accumulated microscopic particles was found to be 39.6 mg/cm
2 /day, and the
extent of the sediment’s effects on coral reefs was
reported to depend on the type and species of
organism.
This network via biogeochemical cycle
between mangroves and coral reefs should be
considered in the discussion of coastal management in Palau.
3.2
Environmental Functions
• Environmental purifi cation functions
Mangroves and tidal fl ats are home to immense
numbers of crabs and snails. When these animals
feed, they reduce the amount of organic materials
in tidal fl ats through their ability to purify their
own habitats.
• Refuges for young coral reef fi sh
During high tides, it is possible to observe
small fi sh swimming in from the sea to forage
among the roots of mangroves. Mangroves are an
especially important source of shelter for young
juveniles that live on coral reefs.
• Provision of habitats to birds, insects, and
other animal species
During low tides, a variety of bird species rest
and carry out feeding activities on the tidal fl ats
that extend from mangrove forests. Additionally,
birds deposit organic matter taken from other
tidal fl ats in the form of droppings. Such biological processes cannot be ignored when large populations of bird species are present.
The diverse types of birds inhabiting tidal fl ats
are also of interest to bird-watchers. The use of
tidal fl ats by birds is not random; some bird species use shorelines and water edges, and others
feed with their feet slightly in the water. Although
tidal fl ats may seem uniform, they should be
understood as a collection of many different environments that are utilized by various types of living organisms.
• Opportunities for food resources
To humans, the most important species in
Palau mangrove ecosystems is the mangrove
crab, and attempts at crab breeding are currently
in progress. Land crabs Cardisoma spp. are also
eaten frequently.
Although some mangrove species, such as
mangrove crabs, have been used as food for people in Palau, it is diffi cult to obtain fi sh-catch statistical data for mangrove areas. This is also true
for information on coral reef fi sh, although data
spanning a 5-year period starting in 2002 have
been made public (2006 Statistical Yearbook,
Republic of Palau, Bureau of Budget and
Planning, Ministry of Finance).
3.3
Socioeconomic
Considerations
• Important resources for environmental
education
Because mangroves have been widely used in
a variety of academic researches, fascinating
discoveries have been made, bearing possibilities
for new academic progress and improvements to
human life. Such information can be used for
Mangrove Forest Ecosystem Services with Reference to the Transportation…