OPTIMALISASI PENGGUNAAN LAHAN DAS SUMANI DENGAN LINEAR PROGRAMMING

Abstract

The usage of watershed-based land requires optimal natural resources management. The optimization of land usage aims to maximize or improve socio-economic and watershed conservation functions or decrease the amount of erosion by counting the resource constraints, resulting in watersheds that have high economic value while the watershed ecosystems are still well preserved. This study aims to 1) know the great value erosion that occurred in the watershed Sumani Solok regency of West Sumatra province, 2) determine the broad allocation of optimal land use. The land usage optimization is carried out through Linear Programming-Simplex method in Ms. Excel. Linear programming models used in solving the problem of allocating limited. The formulated objective function is to obtain the optimal combination of some land usages with the smallest possible erosion value. Meanwhile, the constraint function is expressed based on the limiting constraints in land usage allocation in line with the assumption of allowed erosion, the area of each land usage, the direction of land usage, and the food production of crops. Based on the results of spatial analysis, the actual erosion value of the Sumani watershed in 2017 was 45,823 t / ha / yr. While the optimal land use allocation based on linear programming analysis is 9,505 ha in primary dryland forest, 9,505 ha in secondary dryland forest, 12,142 ha in industrial plantations, 1,392 ha in mixed plantation land, 16,062 ha in paddy fields, and 1,269 ha in scrub land with the minimum erosion value of only 2,229,022 t / yr or 42.73 t / ha / yr.