Tree Diversity and Structure Around Galela Lake, North minush Halmahera Indonesia

This study aims to determine the species of trees around Lake Galela. Data collection was carried out using a transect with a length of 500 m in 4 directions determined by the position of the lake as a central point. Four observation stations are divided into 24 observation plots. The distance of each 100 m plot to occupy 20 × 20 m² Data collection includes tree species, number of individuals, frequency and extent of tree base. Data analysis is carried out with an important vegetation index. The results showed that Lake Galela found 37 tree species from 20 families. Diversity index (H’) at 4 station in the high category, diversity indices value generally showed that species trees has a diverse population. The IVI results show that the tree species with high importance values differs from station to station. species from the four stations that have the highest importance (IVI), namely: Natural Forest area, F. variegata, Plantation area, C. nucifera, Tourisem area, M. indica and around the River area, A. pinnata. This dominant type of tree needs to be conserved because it has a function of water absorption, infiltration, shade, soil retention for sustainability ecosystem surrounding Galela Lake.