Pendugaan Tingkat Bahaya Erosi Untuk Optimalisasi Penggunaan Lahan Studi Kasus Di Desa Lamajang, Kecamatan Pangalengan, Kabupaten Bandung, Das Citarum Hulu

Abstract

Erosion is a major cause of land degradation that lead to critical land formation. Erosion is influenced by several factor, such as : climate, soil erodibility, topograhy, land use, and conservation techniques. Among those five factors the first three factors are factors difficult to change. Therefore, erosion prevention efforts to reduce land degradation generaly focused on the regulation of land use and conservation techniques (land use optimization). Land use optimization was done by allocating any land use for a proper land use in such a way that land degradation can be prevented, i.e land use that produce erosion less than tolerable erosion. Therefore, prediction of actual and potential soil erosion as well as tolerable soil erosion level to determine erosion hazard is necessary. The method used is Universal Soil Loss Equation (USLE) which is a common method used to calculate the erosion rate. The advantages of this method are easy to apply and compatible in areas which have a rainfall and surface runoff as the main factors that causing erosion. The aim of this research is to produce a new scheme of land use based on the level of erosion hazard in order to obtain a sustainable agriculture (optimal allocation of land use) in the Lamajang Village, Sub-district Pangalengan, District of Bandung, West Java. This research includes: field observations, determination of rainfall erosivity, soil erodibility, topography, land use, land conservation techniques, and erosion hazard index. Based on data evaluation and interpretation, 7 land units are found in studied area with erosion rates ranging from low to very high. Land units with erosion hazard greater than tolerance level require land optimization. Optimization of land use activities should include the aspects of erosion, social, cultural, and economic, so make it easy to be accepted and applied for local communities The results of this study showed that erosion hazard in the studied area is very high due to high rainfall and steep slopes. Since actual soil erosion higher than tolerable level it is necessary to optimize the land use. The method of land use optimization suggested for the study area is “Good Terrace”. On areas with slope steepness higher than 60% Agroforestry system is proposed. This Agroforestry system compose of pine as high canopy, coffe or quinine as medium canopy, and chili or tomato as lower canopy (basal cover), that are planted follow contour.