Structure Of The Mangrove Vegetation Community In The Coastal Area Of Melahing Island, Bontang City

This study aimed to identified type of mangrove and community structure of mangrove in the coastal area of Melahing Island, Bontang City. This study was conducted from March 2017, using a three-point transect and each transect there are three observation points at the time of low tide conditions. Data analysis using Density, Relative Density, Frequency, Relative Frequency, Closure, Closure Comparatively, Important Value Index, Diversity Index, Uniformity Index, and Dominance Index. Mangrove species from Stasion I, Station II and Station III are found there are five kind of Rhizophora mucronata, Rhizophora stylosa, Avicennia marina, Avicennia officinalis dan Sonneratia alba with the average stocking mangrove/ha.The results of important value index of Sonneratia alba reflect that mangrove at the study site in good condition, it can be seen that Sonneratia alba has the highest important value index at the tree level, (128,46%), this show the spesies is the type that dominates mangrove vegetation at the tree level. Melahing island has a diversity index values ranging between 0,56-0.66, the value of uniformity index ranges from 0,80-0,94, and the dominance index value range from 0,24-0,33. The result showed that diversity in coastal area of Melahing Island is low.