Hydrological Characteristics Analysis of the Protected Forest as the Upstream Area of the Way Rarem Watershed Using the SWAT (Soil Water Assessment Tool) Modeling

Watersheds are generally divided into upstream, middle, and downstream sections, each characterized by distinct hydrological conditions and land-use dynamics. The upstream area, particularly natural forest ecosystems, plays an important role in regulating water resources. This study aims to analyze the contribution of forest areas to watershed hydrological components using the SWAT (Soil and Water Assessment Tool) model, with a focus on surface runoff (SURQ), subsurface runoff (LATQ), and baseflow (GWQ). Data collection was conducted through ground checks of land cover and river conditions in the Way Rarem Watershed. The collected data were then processed and analyzed using the SWAT model to evaluate the existing hydrological characteristics of the watershed, followed by a specific analysis of the area as the upstream region. The results show that the hydrological characteristics of the Way Rarem Watershed consist of 513,40 mm of surface runoff, 248,35 mm of subsurface runoff, and 602,32 mm of baseflow. Further analysis indicates that the forest area contributes 7,3% to surface runoff, 47,7% to subsurface runoff, and 15,1% to baseflow in the Way Rarem Watershed. These findings highlight the important role of upstream forest areas in regulating watershed hydrological processes, particularly in controlling surface runoff. This study also demonstrates that the SWAT model can be effectively used to quantify the contribution of forest areas to hydrological functions, providing a scientific basis for watershed management and forest conservation planning to support long-term water availability.