Diversity of Flora as Affected by Time Consequences of Revegetation Age in Post Coal Mine Area at PT Berau Coal Tbk, East Kalimantan Indonesia

Abstract

This study aims to examine the diversity of flora in various age classes of revegetation of post-mining coal. This research was conducted at PT. Berau Coal, Binungan block, East Kalimantan. Sampling plots were applied on revegetation land of post-mining coal aged 0, 2, 4, 6, 8 and 10 years, and natural forest as a control. Flora observations were carried out on sample plots of size 25m x 40m for sapling, poles and trees, while sub-plots 1m x 1m for seedlings and understorey. In natural forests observations were made on sample plots measuring 20m x 20m for trees with sub plot 2m x 2m for uderstorey and seedlings, 5m x 5m for saplings, 10m x 10m for poles. The analysis results show that the highest individual density per ha is found in natural forests (seedlings, saplings and poles). The highest of flora index of diversity, richness and evenness were found in natural forests. The flora from revegetation of eight-year has been able to approach to natural forests conditions. The species of plants that predominate in some revegetation age classes are Rhynchospora corymbose (understorey), Senna siamea (seedling, sapling, pole and tree). Acacia mangium and Macarangan hypleoca grow naturally in some revegetation age.