Water provisioning services under changing land use and climate scenarios in the lower Shivaliks of Uttarakhand, India

Dehradun Forest Division (covering 861.48 sq km of geographical area) of lower Himalayas, India contribute to people in variety of ways including water provision, constituted by Asan and Song watersheds and is facing climatic and anthropogenic challenges. Present study aims to quantitatively assess water provision service under changing land use and climate scenarios. Land use and land cover map was made using Landsat data for 1995, 2005, 2015 and 2022. Forest was the dominant class (more than ∼ 70 % of the geographical area) with increasing built-up area (4.85 %) and a reduction of forest (4.30 %) between 1995–2022. InVEST (Annual Water Yield) model was used to estimate water yield (WY) at spatial–temporal scale. Geographical Detector Modelling was applied to identify the potential factors influencing the distribution of water provision. The overall volume of WY increased from 1995 to 2015 with a slight decrease in 2022 with Song has more water provision than the Asan at watershed scale. Bare ground (28.02 %) and built-up (26.54 %) had highest WY due to impact of surface runoff pertaining to impervious soil structure with minimal infiltration belowground. Water provision service were found to be mainly impacted by precipitation, population density, and maximum temperature. Scenario based analysis further substantiated that changes in climate and land use strongly impacted water retention by forest in differential manner. Based on spatial scale and landscape composition of the watersheds, 97.21 % of the area was under trade-off with other nature’s contribution to people. The study provides results that highlight the spatial and temporal dynamics in water yield across various land use classes and forest types, emphasizing on the importance of forest ecosystem in lower Himalayas and their significant contribution to people. This study provides information on water security of urbanizing watersheds in Himalayan ecosystem based on scientific basis and assist policymakers to design resilient forest conservation frameworks, ensuring the long-term ecological stability.