Laju aliran dan erosi permukaan di lahan hutan tanaman jati (tectona grandis, l.f) dengan berbagai tindakan konservasi tanah dan air (studi kasus : rph getas, bkph monggot, kph gundih, perum perhutani unit I Jawa Tengah)

Abstract

Land use activities for a certain purpose without considering soil and water conservation principles could impact negatively on the productivity of land, as well as sedimentation, in the downstream area, and further flood and siltation of rivers and reservoirs. Therefore, reseraches on surface run off and soil surface erosion are necessary as inputs for land manager, to manage the the land to control surgace run-off and soil ersosion as well as`sedimentation. The research was conducted in the area of compartment no 59j, RPh Getas, BKPH Monggot, KPH Gundih Perhutani Unit I Central Java in period November 2010 - March 2011. The aim of this research is to obtain the best practice on teak planting based on surface run off and soil erosion rate. The Benefit of the research is to provide information to formulate policies of teak forest management. The result show that surface run off in plot 1 (teak, corn, and kmelandingan) > plot 4 (bench terraces) > plot 3 (ridge terraces) > plot 2 (ridge terraces), and surface erosion on plot 1 (teak, corn, and kemlandingan) > plot 3 (ridge terraces) > plot 4 (bench terraces) > plot 2 (ridge terraces). The rate of surface run off in each plots are 6734,39 m3/ha/year (plot 1), 2253,94 m3/ha/tahun (plot 2), 3103,44 m3/ha/year (plot 3), dan 3187,43 m3/ha/year (plot 4), while the rate of surface erosion in each plots are 3,11 ton/ha/year (plot 1), 1,01 ton/ha/year (plot 2), 2,26 ton/ha/year (plot 3) dan 2,54 ton/ha/year (plot 4). Based on the results of t-test, the average values of the surface run off of each plots are not significantly different (Vtp1 = Vtp2 = Vtp3 = Vtp4 dan Etp1 = Etp2 = Etp3 = Etp4). Tolarable erosion values in each plot ranges from 16-17 tonnes / ha / year. The result of erosion in each plot show that actual erosion in each plot is lower than tolarable erosion. Based on Erosion Hazard Index criteria published by the Ministry of Forestry, and soil solum of 60-90 cm the erosion of each plot is categorized as low. This Research concludes that, actual erosion in each plot is lower than tolarable erosion. The making of gulud terraces and bench terraces can reduce surface runoff and erosion, compared with plots that do not use the terrace. Based on criteria of surface rum off and surface erosion, the utilization of ridge terraces, is the best soil and water conservation measures in application of teak planting.

Land use activities for a certain purpose without considering soil and water conservation principles could impact negatively on the productivity of land, as well as sedimentation, in the downstream area, and further flood and siltation of rivers and reservoirs. Therefore, reseraches on surface run off and soil surface erosion are necessary as inputs for land manager, to manage the the land to control surgace run-off and soil ersosion as well as`sedimentation. The research was conducted in the area of compartment no 59j, RPh Getas, BKPH Monggot, KPH Gundih Perhutani Unit I Central Java in period November 2010 - March 2011. The aim of this research is to obtain the best practice on teak planting based on surface run off and soil erosion rate. The Benefit of the research is to provide information to formulate policies of teak forest management. The result show that surface run off in plot 1 (teak, corn, and kmelandingan) > plot 4 (bench terraces) > plot 3 (ridge terraces) > plot 2 (ridge terraces), and surface erosion on plot 1 (teak, corn, and kemlandingan) > plot 3 (ridge terraces) > plot 4 (bench terraces) > plot 2 (ridge terraces). The rate of surface run off in each plots are 6734,39 m3/ha/year (plot 1), 2253,94 m3/ha/tahun (plot 2), 3103,44 m3/ha/year (plot 3), dan 3187,43 m3/ha/year (plot 4), while the rate of surface erosion in each plots are 3,11 ton/ha/year (plot 1), 1,01 ton/ha/year (plot 2), 2,26 ton/ha/year (plot 3) dan 2,54 ton/ha/year (plot 4). Based on the results of t-test, the average values of the surface run off of each plots are not significantly different (Vtp1 = Vtp2 = Vtp3 = Vtp4 dan Etp1 = Etp2 = Etp3 = Etp4). Tolarable erosion values in each plot ranges from 16-17 tonnes / ha / year. The result of erosion in each plot show that actual erosion in each plot is lower than tolarable erosion. Based on Erosion Hazard Index criteria published by the Ministry of Forestry, and soil solum of 60-90 cm the erosion of each plot is categorized as low. This Research concludes that, actual erosion in each plot is lower than tolarable erosion. The making of gulud terraces and bench terraces can reduce surface runoff and erosion, compared with plots that do not use the terrace. Based on criteria of surface rum off and surface erosion, the utilization of ridge terraces, is the best soil and water conservation measures in application of teak planting.