Optimization Model of Land Use Planning to Reduce Land Erosion Level: Case Study in the Upper Ciujung River Basin

Abstract

Uncontrolled changes in land use located in the upstream river can result in land erosion, which will eventually increase river sedimentation as well as floods, reduce the estimated planned life of the downstream reservoir, and reduce soil productivity due to the loss of nutrients. This study is aimed to find the best land use pattern through optimization, in order to reduce the level of land erosion. The optimization model used is the Linear Programming (LP) method which is combined with the USLE method and Geographic Information System software based on raster grids. The potential sedimentation prediction that is collected from the measurement data in the river is used to calibrate the simulation of the real conditions of land erosion. The optimization results of this study in the Upper Ciujung river basin, Banten, can be obtained by expanding as much as possible the area of corn-fields/moors to become plantations (which are denser and bigger tree fields) or even forests. The results can reduce the level of land erosion by 38.0%, or from 99.03 tons/ha/year to 61.32 tons/ha/year. However, the results above cannot be generally applied in all locations. What can be generally accepted is that the optimization model of this study can be used to reduce the level of land erosion by regulating the size of the area and location of each type of land use, and by considering the factors of soil erodibility, slope, and rain erosivity at the site.

Keywords

• land erosion
• land use
• linear programming