Analysis on the coral reef habitat change using KOMPSAT-2 images

Abstract

Coral reefs and associated tropical nearshore ecosystems have suffered massive, long-term decline in abundance, diversity, and habitat structure due to overfishing and pollution. Especially, the global warming has lead to the global decrease in the coral reefs recently, thus the coral reef habitat can be a good indicator of environmentalchange in a tropical coastal area. In this study, we carried out the analysis of coral reef habitat change using KOMPSAT-2 images in Weno island, Chuuk lagoon of Federated States of Micronesia. A field campaign was performed for collecting real reef habitat data in 2008 and 2011. The satellite image was acquired on September 2008 and 2010. For classification of KOMPSAT-2 images, we employed an object-based classification method which has been considered to be effective for high spatial resolution satellite images. The produced habitat map was validated by a comparison with the in-situ observations. The overall accuracy calculated from the classification results of the KOMPSAT-2 image in 2008 was 84.62 %. And The KOMPSAT-2 image acquired in 2010 was 87.25%. In addition, area of coral reef habitat mapping has changed during 2 years. Through the research, highresolution satellite images can be possible to monitor of coral reef habitat change.