Vegetation Diversity and Biomass of Certain Types of Peatland Use In Kepulauan Meranti Regency, Riau. Under academic

Abstract

The purpose of this study was to assess the diversity of vegetation and biomass on the three different peat land use types; natural forests, gardens, and industrial forest plantation of sago areas (HTI sago). The results showed that the composition of plant species for three growth rates, saplings, pole, and trees stages, ware different among three different peat land use types. The dominant species in natural forests were Shorea parvifolia, Shorea uliginosa, Baccaurea bracteata and Palaquium rostratum. In gardens, the dominant species are Metroxylon spp., Artocarpus sp., Palaquium ridleyi, and Alstonia spatulata Blume.; while in HTI sago areas, including Metroxylon spp, the presence of other species of forest vegetation were Ficus microcarpa, Combretocarpus rotundatus, Baccaurea bracteata and Palaquium rostratum. The higher diversity index of three different growth rates; saplings (2.75), pole (2.99) and trees (3.15) respectively, were only found in the natural forest. On the contrary, the lower diversity index of sapling stage (1.95) was in gardens and both the pole (0.77) and tree (0.44) were belonged to the HTI sago. Potential biomass of pole stages figured out the higher and the lower value were 359,01 ton ha-1 in HTI sago, 159,75 ton ha-1 in gardens and 67,79 ton ha-1 in natural forest, respectively. This trend also occurred nearly equal to the higher stages of trees and a lower value were 209.20 ton ha-1 in HTI sago, but the natural forest 161.13 ton ha-1 higher than the gardens, 107.22 ton ha-1, respectively.

biomassa atas permukaan pada penggunaan lahan gambut berupa hutan alam, kebun rakyat dan areal HTI Sagu. Penelitian ini dilaksanakan di areal HPH PT. National Timber and Forest Product Unit HTI Murni Sagu (Sekarang PT. Sampoerna) di Kabupaten Kepulauan Meranti (sebelumnya Kab. Bengkalis) Provinsi Riau. Penelitian lapangan dan Laboratorium dilaksanakan selama kurang lebih tiga bulan, dimulai pada bulan September sampai dengan bulan November 2008. Obyek penelitian ini adalah hutan gambut pada tiga komunitas hutan, yaitu Hutan Alam, Kebun Rakyat dan areal HTI Sagu. Pengambilan data analisis vegetasi dilakukan dengan cara jalur atau transek dan pembuatan petak contoh dilakukan secara purposive systematic sampling berdasarkan kerapatan tegakan dan tipe penggunaan lahan. Selanjutnya dibuat 5 buah petak contoh berukuran 20 m x 20 m pada masing-masing komunitas hutan. Pada setiap petak contoh dibuat sub petak contoh - sub petak contoh secara nested sampling dengan ukuran 20 m x 20 m, untuk tingkat pohon, 10 m x 10 m untuk tingkat tiang 5 m x 5 m untuk tingkat pancang.