| Summary: | Opak Hulu sub watershed is an area with relatively dense population. Moreover, it has also an important role to maintain ecosystem sustainability of its surrounding areas. These situations requested land evaluation and land use planning to prevent its utilities to degrade the land that could be indicated by soil erosion rate. Thus, this study aimed to find optimal land use with minimum erosion.
The study area was modeled as land units that resulted by overlaying maps of: soil, slope, rainfall intensity, and actual land use. The calculation of predicted erosion was done using USLE equation. Linear program and Arc View GIS software were used to find the optimum land use allocation.
Results of the study shown that Opak Hulu sub watershed was dominated by flat area, medium rainfall intensity, land use as farm land, and sandy regosol soil that was prone to erosion. Thus, this area has predicted actual erosion 23,12 tons/ha/yr and on the other hand, tolerated erosion was 2,3 ton/ha/yr. The optimation suggested that forest and annual crop area should be increased by converting all bushes and sandy area, and also part of grassed and arable farm. Predicted erosion of optimal land use allocation was 3,6 ton/ha/yr.
Key word: Landuse planning, erosion, optimation
|
|---|