STRUKTUR VEGETASI EKOSISTEM HUTAN MANGROVE DI KECAMATAN MERBAU KABUPATEN KEPULAUAN MERANTI

Abstract

This research aimed to determine the vegetation structure of natural and rehabilitated mangrove and to analyze the differences of mangrove vegetation structure between natural and rehabilitated areas. This research was conducted during the period of November to December 2014 in Merbau Meranti Island at two different locations. This research used survey method and the primary data was collected from the field. The sample collection used 10 x 10 m nested plot. A total of eight mangrove species were found in this research that belong to four families (Rhizoporaceae, Avicenniaceae, Sonneratiaceae, Arecaceae). Rhizoporaceae consists of Rhizopora apiculata, Rhizopora mucronata, Rhizopora stylosa and Bruguiera sp. Avicenniaceae consists of Avicennia marina and Avicennia alba. Sonneratiaceae consists of Sonneratia sp., while Arecaceae consists of Nypa fruticans. In natural mangrove area, the highest INP was found in Rhizopora apiculata at level of saplings (INP : 73.29%) and at the level pole (INP : 61.91%). In rehabilitated mangrove area, the highest INP was found in Avicennia alba at level of saplings (INP : 80.25%) and Sonneratia sp. and level of pole (INP : 52.51%). The diversity of mangrove vegetation at two study sites are moderate, however rehabilitated mangrove areas are more natural than mangrove area. The results of Tukey test (T test) showed that there were significant differences in the diversity index between natural and rehabilitation mangrove forest. The results showed that replanting mangrove vegetation had considered the suitability of zoning and there were similarity of community vegetation structure. These results indicated that the mangrove forest ecosystems in both sampling sites was in the regeneration phase with the abundance of seedlings and saplings.