Land use changes impact on water quality in Jeneberang Watershed, South Sulawesi, Indonesia

Abstract

Land use change and water quality problems occur in most watersheds in Indonesia, which are also resulted by climate change phenomenon. One of the watersheds that have a critical status but have an important role in South Sulawesi, Indonesia is the Jeneberang watershed, which is included in 15 national priority watersheds for restoration and conservation. The purpose of this study is to analyze the impact of land use changes in watersheds over the last 20 years on water quality. This research is a descriptive study using quantitative and qualitative methods. In this study, Land Change Modeler (LCM) module was used in Idrisi Terrset software to analyze changes in used/covered by comparing the imagery of 2000 and 2020, while water quality analysis using the pollution index method on 7 key parameters of water quality. The results showed a decrease in forest area cover in the upstream part of the watershed with an increase in the area of agricultural areas and settlements. Water quality was classified as lightly polluted with the pollution index values increased from upstream (2.04), middle (2.12,) to downstream (2.83). Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and Coliform concentrations were higher than national standards of water quality. Changing land use into agricultural areas and settlements has contributed to increased water pollution in the Jeneberang watershed.