Keadaan Tegakan dan Petumbuhan Shorea spp. pada Areal Bekas Tebangan dengan Teknik Silvikultur Tebang Pilih Tanam Indonesia Intensif (Di Areal IUPHHK PT.Erna Djuliawati)

Abstract

INTRODUCTION. Some introduced and implemented sylviculture systems in Indonesia are Clear Cutting with Natural Regeneration (THPA), Clear Cutting with Artificial Regeneration (THPB), Selective Cutting of Indonesia (TPI), Indonesia Selective Cutting with Planting (TPTI), Selective Cutting with Strip Planting (TPTJ), and The Intensive Indonesian Planting and Selective Cutting (TPTII). This research wants to know the effects of land slope level to Shorea spp. regeneration using The Intensive Indonesian Planting and Selective Cutting (TPTII) sylviculture technical, in view of both natural and artificial regeneration is very important to the forest stand sustainability on the next growth period. So, this research gives some informations to the company, on what slope level Shorea spp. can adapt and grow optimally. MATERIAL AND METHODS. This research was conducted on three different forest condition, i.e. primary forest, first year LOA TPTII (Et+1 forest), and second year LOA TPTII (Et+2 forest). This research used line transect sampling by 100 m x 100 m. In that plot, there are sub-plots, subplot of tree by 25 m x 20 m (22 m x 20 m after stripping), sub-plot of pole by 10 m x 10 m, subplot of sapling by 5 m x 5 m and sub-plot of seedling by 2 m x 2 m. Soil analyzed at Soil Fertilization and Chemical Laboratory, Soil Departement, Faculty of Agriculture IPB. Research equipments were map, phiband, haga hypsometer, brunton compass, pole, tally sheet, ropes, vegetation book, chopping knife, stationery, ring sample and paint. On those three different forests, the research was also conducted vegetation analysis, picking out of soil sample, mesuring height and diameter of seedling at the planting strip. And then regression analysis was conducted to know the relationship between plant growth and land slope. RESULT AND DISCUSSION. The result shows that in primary forest, the highest number of species was on middle slope level (15-25%), in the amount of 51 on tree rate. In first year LOA TPTII (Et+1 forest), the highest number of species was on steep slope level (>25%) in the amount of 62 on tree rate and in second year LOA TPTII (Et+2 forest), the highest number of species was on steep slope level (>25%), in the amount of 61 on sapling rate. Coefficients of the similar community that has a high average value of the similar community (>50%), on the flat slope level (0-15%) there were first year LOA TPTII (Et+1 forest) and second year LOA TPTII (Et+2 forest). On steep slope level (>25%), there were primary forest and first year LOA TPTII (Et+1 forest). At the same time, all communities on middle slope level (15-25%), has similarity value under 50%. The diversity of species in both primary forest and LOA TPTII shows that the value is more that 2.00. It means that the diversity in primary forest first year LOA TPTII (Et+1 forest), and second year LOA TPTII (Et+2 forest) was classified at middle to high. According to the data of regression analysis, both diameter and height of first year plant, the probability value of Shorea spp. diameter is 0.357 and the probability value of Shorea spp. height is 0.16. The probability value of Shorea spp. diameter on second year LOA TPTII (Et+2 forest) is 0.024 and the probability value of Shorea spp. height is 0.012.