THE UNCERTAIN FUTURE OF LANDSCAPES SUBJECTED TO MOUNTAINTOP REMOVAL MINING

Human disturbances have dramatically altered large portions of Earth’s surface. One of the most infamous examples of human-induced topographic change is mountaintop removal (MTR) mining, which has affected over 6000 km² of topography in the central Appalachians, USA. While MTR mining causes well-documented degradation of downstream water quality and aquatic habitat, little work has focused on the long-term geomorphic consequences of MTR mining. Recent studies suggest that MTR landscapes might experience erosion dynamics distinct from those in unmined landscapes due to alterations to topography, hydrology, vegetation type and distribution, and surface material properties caused by mining and subsequent reclamation. Given the fundamental changes MTR mining causes in the landscape, as well as the known pollution hazards posed by mine waste, it is critical to understand how MTR landscapes will evolve in the future. Here we use the HyLands landscape evolution model to explore the long-term effects of mining-induced changes to landscape form, surface water discharge regimes, vegetation, and surface sediment grain size. Comparing landscape evolution trajectories and sediment yields between model runs using pre- and post-mining digital elevation models isolates the effects of topography on future landscape evolution, with hydrology, vegetation, and grain size changes each assessed using model modifications sourced from the literature. Initial results suggest that mining-induced topographic change may be the dominant factor in controlling post-reclamation landscape evolution, implying that the topographic form of reclaimed mines matters at least as much as better-studied aspects of post-mining landscapes like hydrology and vegetation dynamics. These results have important implications for restoring degraded land and protecting ecological and human health in an uncertain future.