A modeling framework for disentangling the impacts of changing climate and land uses on terrestrial water-carbon balance under SSP-RCP scenarios
| Authors: | Xiaola Wang, Jiangchao Qiu, Kai Duan, Ge Sun, Jianhua Wang, Huan Liu, Xuanxuan Wang, Peng Hu |
| Year: | 2026 |
| Type: | Scientific Journal |
| Station: | Southern Research Station |
| DOI: | https://doi.org/10.1016/j.ejrh.2026.103303 |
| Source: | Journal of Hydrology: Regional Studies |
Abstract
Study region: The Pearl River Basin (PRB) in South China
Study focus: Understanding impacts of climate and land use changes on terrestrial water-carbon balance is critical for sustainable water-land management and climate change adaptation. Yet attributing responses to individual drivers remains challenging. We develop an integrated modeling framework to quantify contributions of changes in climate and land use and their offsetting effects on key ecohydrological fluxes. New hydrological insights for the region: In the PRB, we evaluate water and carbon flux responses to climate (precipitation, potential evapotranspiration (PET)) and land use patterns (e.g., forest and urban) across SSP-RCP scenarios (SSP126, SSP370, SSP585) in the near future (NF, 2021–2050) and far future (FF, 2071–2100). Climate drivers generally exert stronger impacts on water and carbon fluxes than land use drivers across the PRB, whereas land use impacts are non-negligible and spatially heterogeneous. Specifically, urbanization increases runoff (R) (up to 34% under NFSSP585) and reduces net ecosystem productivity (NEP) (up to 8% under FF-SSP585), most pronounced in the Pearl River Delta. In contrast, forest expansion reduces R and enhances carbon sequestration especially in Dongjiang River Basin. PET impacts on regional carbon sinks are highly scenario-dependent: higher PET enhances carbon fluxes via increased actual evapotranspiration in the NF, whereas under FF-SSP370 and FF-SSP585, persistently elevated PET induces hot-dry stress that outweighs positive drivers and suppresses NEP.