Species composition and structure of mangrove in Tamo Rocky Cliff Beach Majene (West Sulawesi, Indonesia)

Abstract

West Sulawesi is locally well known for its rocky cliff beach along the coastline between Majene and Mamuju regency. Dato beach in Majene, for instance, is popular for tourism destination. In the area between Tamo, a small fisherman village and Dato can be found one rocky cliff beach with beautiful scenery. Cliff height varied between 5 m - 60 m. At the base of the rocky cliff stretched a fairly extensive mangrove which is separated from the cliff by the lagoon. This mangrove vegetation is thick, however, the species composition and structure remain unknown. Therefore, research is required to become important information in managing biological resources around the mangrove forest area. The research aims to know the species composition and structure of the mangrove communities in the Tamo rocky cliff beach. The sampling method used purposive sampling with four transects. All transects are combined with nested quadrat. A series of quadrat size, which is 1 x 1 m, 5 x 5 m and 10 x 10 m were used for counting the densities of mangrove seedling, stake, and trees respectively. All transect was set up crossing the mangrove area and perpendicular to the coastline. The result showed that mangrove composition consists of five true mangrove species, such as Avicennia marina, Bruguiera gymnorrhiza, Rhizophora mucronata, Rhizophora stylosa, Sonneratia alba with various associated mangrove species. Diversity and Evenness index was extremely low. In contrast, Simpson and Similarity index was high. Composition and structure of mangrove vegetation in Tamo rocky cliff beach dominated by monoculture stake of Rhizophora stylosa which is an importance value (IV) range between 182.90% - 300%.