BENTHIC HABITAT ON CORAL REEF ECOSYSTEM IN MENJANGAN ISLAND

Abstract

Coastal ecosystems covering three important parts of mangroves, seagrass beds and coral reefs are an integral part of the habitat mapping process. This study aims to mapping habitats of the island of Menjangan in West Bali National Park (TNBB), Bali. Field data was collected in February, April and August 2017. Total 110 sampling points spread across the coastal area of Menjangan island by looking at the texture differences using the ENVI v4.7 program from satellite image data Worldview 2 October 14th 2016. The results showed that the study area is divided into 6 types of main habitat (geomorphological levels) i.e., reef front, reef slope, reef flat, Sand and Terrace on which we add the mangroves, Ground-truhing data and cross-reef photograph-transects of habitats described with with medium scale approach suggest that, on reef flat and crest areas, 12 habitats has been described. This includes coral habitat (coral>30% cover) dominated by several types of hard coral (Scleractinia) ie Acropora sp, Montipora sp, Porites lutea and Porites cylindrica; mixed with rubble and algae (mostly Chlorophyta and Phaeophyta) each covering about 15%. Sand (10-15%) and seagrasses (including Syringodium sp, Cymodocea sp and Thalassia sp) (10%) are more marginally present. The blue coral Heliopora coerulea (non Scleractinia), mixed coral associations, and dead corals complete the assemblages . On the reef flat rugosity is low (1 – 2) but increases toward the crest and front reef with rugosity level at 3 - 4. On this research it can be one of data support for re-zonation in West Bali National Park especially in Menjangan Island and surrounding area.