Spatial Distribution of Hydrological Services in Sichuan Forest Ecosystems Using LPJ Model

ABSTRACT Amid escalating climate extremes in the 21st century, the hydrological regulatory functions of forest ecosystems have become crucial for climate adaptation strategies. Sichuan Province, encompassing critical headwaters of the Yangtze and Yellow River basins, sustains 23.7 million hectares of forests with distinctive elevational gradients (500–7500 m). This study implements the Lund–Potsdam–Jena Dynamic Global Vegetation Model (LPJ‐DGVM) coupled with multitemporal Geographic Information Systems analysis (2010–2022) to systematically evaluate forest hydrological services. Through terrain‐adjusted hydrological modelling and spatial clustering techniques, we quantify water retention capacities (annual average 2850 ± 320 m 3 /ha) and humidity stabilization effects (relative humidity enhancement: 8.3%–15.7%) across four major forest types. Geographically weighted regression reveals significant spatial heterogeneity in soil moisture storage (18.5–33.8% vol) and evapotranspiration rates (2.2–3.6 mm/day), with 62% of variations explained by bioclimatic drivers (temperature‐precipitation synergy, r = 0.68) and anthropogenic pressure indices (population and gross domestic product composite, r = 0.59). Our proposed optimization framework integrates three implementation phases: (1) priority conservation of 12 critical water‐yield zones (identified through hydrological sensitivity analysis), (2) rehabilitation of 850 km riparian corridors connecting fragmented habitats and (3) systematic resource integration through multifunctional landscape design. Scenario projections estimate 16%–24% enhancement in hydrological regulation efficiency, demonstrating viable pathways to reconcile ecological security (water provision capacity +19%), economic viability (ecotourism potential +28%) and social equity (disaster risk reduction for 4.3 million residents).