TITLE:
Inexpensive Method to Assess Mangroves Forest through the Use of Open Source Software and Data Available Freely in Public Domain
AUTHORS:
Fatwa Ramdani, Sabaruddin Rahman, Putri Setiani
KEYWORDS:
Mangroves, Coastal Zone, Classification, Remote Sensing, Landsat TM/ETM+, Indonesia
JOURNAL NAME:
Journal of Geographic Information System,
Vol.7 No.1,
February
2,
2015
ABSTRACT: Mapping and assessment of
mangrove environment are crucial since the mangrove has an important role in
the process of human-environment interaction. In Indonesia alone, 25% of South
East Asia's mangroves available are under threat. Recognizing the availability
and the ability of new sensor of Landsat data, this study investigates the use
of Landsat ETM + 7 and Landsat 8, acquired in 2002 and 2013 respectively, for
assessing the extent of mangroves along the South Sulawesi’s coastline. For
each year, a supervised classification of the mangrove was performed using open
source GRASS GIS software. The resulting maps were then compared to quantify
the change. Field work activities were conducted and confirmed with the changes
that occurred in the study area. Considering the accuracy assessment, our
study shows that the RGB composite color-supervised classification is better
than band ratio-supervised classification methods. By linking the open source
software with the Landsat data and Google Earth satellite imagery that is
available in public domain, mangroves forest conversion and changes can be
observed remotely. Ground truth surveys confirmed that, decreases of mangroves
forest is due to the expansion of fishpond activity. This technique could
potentially allow rapid, inexpensive remote monitoring of cascading, indirect
effects of human activities to mangroves forest.