Future Hydrological Trajectories of Burdur Lake Under Climate Change and Basin‐Scale Human Interventions

ABSTRACT Burdur Lake is a saline lake in southwestern Türkiye that has lost approximately 75 km 2 , or one‐third of its surface area, since 1975. The basin's hydrology has been significantly modified by human activities, including reservoir construction, and water level declines continue with no signs of stabilisation. In this study, the soil and water assessment tool (SWAT) was employed to simulate the hydrological processes in the Burdur Lake Basin and analyse the cumulative impacts of climate change and hydrological modifications. The model incorporated a digital elevation model, land use/cover and soil maps and historical meteorological data. Calibration and validation were performed using the SUFI‐2 algorithm within SWAT‐CUP, based on streamflow and water volumes in major reservoirs and Burdur Lake. Future hydrological conditions were projected by running bias‐corrected precipitation and temperature data from three global climate models (GFDL‐ESM2M, HadGEM2‐ES, MPI‐ESM‐MR) under RCP4.5 and RCP8.5 scenarios for 2025–2098. Results indicate that the Burdur Lake Basin can face a 5%–10% decrease in precipitation under RCP4.5 and a 14%–20% decrease under RCP8.5, with minimum and maximum temperatures rising by about 5°C relative to historical values. Simulated lake volumes and levels show continued declines, with water levels falling below the ecological threshold of 835 mASL under all RCP8.5 projections and the HadGEM2‐ES RCP4.5 scenario. Although the decrease in water level is slower than in the historical period, the downward trends are projected to continue. This study shows that climate change could create additional stressors on the already altered hydrological conditions of Burdur Lake. Implementation of adaptive and integrated water management strategies is essential to prevent further degradation in the lake's ecological and hydrological balance.