Sedimentation Analysis Using SWAT Model (Soil And Water Assessment Tool) In Mamasa Sub Watershed Nur Isra (a*), Usman Arsyad (b), Zulkarnain Chairuddin (c)
a*) Environmental Resource Management, Postgraduate school, Hasanuddin University, Makassar, South Sulawesi, 90245, Indonesia
*isran21p[at]student.unhas.ac.id
b) Faculty of Forestry, Hasanuddin University, Makassar, South Sulawesi, 90245, Indonesia
c) Department of Soil Science, Faculty of Agriculture, Hasanuddin University, Makassar, South Sulawesi, 90245, Indonesia
Abstract
Erosion and sedimentation in the upstream area of the sub-watershed have resulted in a decrease in the quality of agricultural land, such as a decrease in soil fertility. This decrease in soil fertility is due to the loss of NPK nutrients that occur in the top soil. Erosion and sedimentation in the upstream area of the Mamasa Sub-watershed are caused by land degradation and forest conversion due to land expansion and shifting cultivation for the cultivation of cocoa, corn and coffee. The purpose of this study was to determine the amount of sediment in the Mamasa Sub-watershed, Mamasa Regency using the SWAT model. This research was conducted in the Mamasa Sub-watershed from June to September 2022 through several stages in the form of literature study, primary and secondary data collection. Then proceed with laboratory analysis, making a base map to the data analysis process. SWAT requires input data in the form of land cover, soil type maps, slope maps, and climate data. The SWAT simulation was carried out in the 2012 to 2021 timeframe. The sedimentation values obtained from the SWAT model were sediment values from 0.06 to 34.073.01 tons/ha (55.34%), sediment values from 34.073.01 to 95.323.59 tons/ha (23.27%), sediment value 95.323.59 to 225.951.47 (13.51%), sediment values 225.951.47 to 442.013.09 (6.23%), and sediment values from 442.013.09 to 1,415.454.83 (1.66%). Based on this research, it can be concluded that the highest average sediment is found in the downstream area with an area of 38,875.66 ha
Keywords: Sediment- SWAT Model- Sub Watershed Mamasa
Topic: Agriculture adaptation to environmental changes
