Quantifying China's ecological assets: A carbon-based assessment of climate change and land use change effects using generalized additive models

Ecological assets provide vital ecosystem services that sustain human well-being, yet face severe threats from climate change and land use change (CC-LUC). This study evaluates ecological assets in China and quantifies the relative and synergistic effects of CC-LUC using a novel approach based on carbon asset valuation, employing total organic carbon pool per unit area as an ecosystem service value equivalent factor. China's ecological assets in 2021 totaled $164 trillion, with cropland ($1.10 trillion), forest ($7.35 trillion), grassland ($153.17 trillion), wetland ($0.04 trillion), desert ($2.08 trillion), and water bodies ($0.30 trillion) showing significant regional variations from 2001–2021. Climate change predominantly drove cropland value changes in Northern China and wetland changes in Western China, while land use changes more significantly impacted croplands and forests in Western China. Generalized Additive Models reveal complex synergistic CC-LUC effects across land types. Cropland, forests and grasslands exhibited initial growth followed by diminishing returns, while wetlands, deserts and water bodies showed initial decline at lower CC-LUC levels followed by improvements at higher levels, indicating potential resilience beyond certain thresholds. The findings underscore the necessity for tailored conservation strategies, highlighting the efficacy of sustainable practices in certain regions and the urgency for targeted interventions in others. This study contributes to research on ecological asset valuation and provides insights for policymakers developing strategies to mitigate CC-LUC impacts on ecosystem services.