Relative and Cumulative Effects of Climate and Land Use Change on Hydrological Ecosystem Services in Northeast China

Climate change (CC) and land use (LUC) have been determined as two major environmental variables that broadly affect hydrological ecosystem services (HESs). However, the relative cumulative effects of CC LUC on HES at large spatial scales where there is great heterogeneity still unclear enough to support formulation update decision-making ecological management policies. This study has quantified spatiotemporal HESs (water yield, water purification, soil retention) from 1992 2020 in northeast China, evaluated contribution through setting scenarios using indicators (the Relative Importance Index Combined Effects Index). yielded following results: (1) From 2020, yield (WY) (+94.33 mm) retention (SR) (5.28 × 103 t/km2) both showed an upward trend nitrogen export (NE) indicating a decline purification (WP). (2) There was significant which included increases WY Sanjiang Plain; NE Songnen Plain (SNP), (SJP), Liao River (LJP); SR Greater Khingan Mountains (GKMR), Lesser (LKMR), Changbai (CBMR). (3) more affected by than LUC, especially SJP, eastern LRP, southern CBMR; western GKMR, southwestern SNP; GKMR; intensity gradually increased CBMR LKMR. (4) The effect contributed most regions but inhibited some regions; warming forestland expansion significantly WY. Our emphasizes current policies practices should consider maintain diverse ensure human well-being.