| dc.description.abstract | Abstract
Background: The mangrove forests in Balikpapan Bay, Indonesia,
have been used as a source of livelihood for local community more
than 150 years. Since the natural products of the mangrove forest,
such as wood and seafood, are not able to meet the economic needs
of the local community, some areas have been converted into
brackish water ponds with traditional aquaculture systems. The
growth of brackish water ponds over the last five decades has been
identified as the main cause of ecosystem destruction. However, the
mangrove ecosystem has been restored naturally through tidal action
and seeds falling from mangrove trees.
Methods: This study focused on the mangrove tree species
Rhizophora apiculata, with ages ranging from 3 to 40 years. Initially,
the study site (area, 1 ha) was plotted. The study sample size included
30% of the local population, chosen by systematic random sampling.
The data collection was undertaken as follows: 1) measurement of the
diameter and height of mangrove trees; 2) observation of local fish
auctions; and 3) interviewing of fishers and local communities
regarding the direct use of the natural products of the mangrove
ecosystem.
Results: It is suggested that the total income from wood production is
IDR 742,425,000 year-1 or US $0.933 person-1 day-1. Furthermore, the
total income from fishing is IDR 1,019,056,640 year-1 or US $1.28
person-1 day-1. Pre-thinning income level for wood harvesting is still
low. The income difference between wood production and fishing
resulted in the rate of overfishing reaching 37.3%. The highest
observed wood production was reached at the age of 25 years, and
the highest value of mean annual increment (MAI) is 5.39 m3 ha-1 at
the age of 40 years.
Conclusions: This study showed that tree thinning, ranging from 90
to 350 trees ha-1, can increase the value of MAI by around 24.5%. | en_US |
