Land use change analysis and the impact on the streamflow of the Keureuto River

Abstract

The increasing of population is proportional to the natural resource’s exploitation. Over the past few decades, the activity has converted the natural land into agricultural and plantation fields, urbanized areas, and other types of use. In some watershed systems, land use conversion has reduced the system’s capability both in sustaining water resources and in preventing extreme runoff. Such is the case of the 302 km2 Krueng Keureuto Watershed which supports the water supply for the North Aceh District, both for irrigation and municipal use. Therefore, this study aims to investigate the land use change in the system and its impact on the streamflow. The land use is classified based on the Landsat satellite images of the year 2015 and 2021, using the Supervised Classification tool in ArcGIS. The impact is investigated using a Hydrologic Modelling System (HEC-HMS). The outlet is defined based on the Automatic Water Level Recording (AWLR) station downstream of the Keureuto River. A significant reduction of the forest is estimated at 27.67% in seven years. In contrast, the land use types such as urbanized areas, agricultural fields, and shrubs are increasing to 6.34%; 4.75%; and 5.75%, respectively. Based on the model simulation it is confirmed that the changes in land use have altered the river flow regime.