From Coalfields to Carbon Sinks: Examining the Policy Effects on the Dynamics of Ecosystem Services in the Watersheds of Eastern Kentucky, USA

The Big Sandy River Basin (BSRB), which comprises the majority of the surface-mined and reclaimed areas, is a key restoration landscape in Eastern Kentucky. BSRB has a long history of coal mining, followed by various policies adopted to restore the post-mining ecosystems. Kentucky designates priority watersheds (PWs) within major river basins to address environmental issues and direct resources for focused implementation through coordinated efforts. However, clear watershed-scale evidence evaluating ecosystem service (ES) patterns in relation to these policy designations remains limited. Therefore, we conducted spatial and temporal mapping of carbon storage (CS) and sequestration (CSE) from 2001 to 2021 across selected PWs and NPWs, utilizing the National Land Cover Dataset (NLCD) and the InVEST model. The results revealed only a modest net increase in CS in both PWs (+0.93%) and NPWs (+0.16%) from 2001 to 2021. However, CSE patterns exhibited a trajectory towards recovery. Both PWs and NPWs experienced carbon loss during 2006-2011 and followed a gain afterwards until 2021. Between 2001 and 2021, CSE values were nearly 6.5 times higher in PWs (2.27 Mg C/ha) than in NPWs (0.35 Mg C/ha). The economic valuation (EV) of the CS revealed that the landscape offers climate-regulating ES worth more than 6100 USD/ha across years. This study utilized spatial statistics (Moran’s I test) that identified regions with high-high value and low-low value clusters and outliers of CSE across time. These findings support prioritization and monitoring in post-mining watersheds and provide an assessment framework for linking LULCC, ES, and watershed-level policy focus.