Lake carbon storage as environmental impact indicator: A multi-decadal assessment framework for evaluating sustainable development pathways

Abstract

Rapid environmental impact assessment (EIA) of urban development traditionally relies on static indicators that fail to capture cumulative effects and sustainability transitions. We develop an innovative impact assessment framework using dissolved organic carbon (DOC) storage as a sensitive environmental indicator to evaluate the cumulative impacts of economic development policies. Our methodology integrates 36 years (1987–2022) of Landsat-derived chromophoric dissolved organic matter data, lake bathymetry, landscape pattern analysis, and composite socioeconomic indices to quantify column-integrated DOC dynamics in China's Chaohu Lake. The framework reveals that while DOC storage declined overall (−0.065 g m⁻² yr⁻¹), landscape drivers dominated system responses, with grassland degradation (29.5 %) and fragmentation (16.3 %) emerging as primary impact factors. Critically, our Tapio decoupling analysis exposes hidden sustainability trade-offs: long-term strong decoupling between DOC loss and urbanization indices demonstrated “green development” effectiveness, yet rapid industrial restructuring policies (2017–2018) triggered expansive coupling and negative decoupling states, temporarily reversing environmental gains. This methodological advancement transforms EIA from reactive project evaluation to proactive sustainability monitoring, establishing lake carbon storage as a transferable early-warning indicator for policy-environment interactions. The framework enables planners to quantitatively assess whether economic transitions remain within planetary carbon limits while advancing Sustainable Development Goal 11, providing a paradigm shift towards adaptive EIA for sustainable urban development.