
Abstract
This study investigates the effects of deforestation and climate change on water flow regulation within the mixed-deciduous-forest-dominated Upper Nan Watershed in Northern Thailand. Using the SWAT model, hydrological changes were analyzed under 16 land-use scenarios and CMIP5 climate projections (RCP4.5 and RCP8.5) for both historic (1980–2020) and future (2021–2080) periods. Findings reveal that increasing rainfall variability under RCP8.5 amplifies hydrological






