Assessing habitat heterogeneity and vegetation outcomes of geomorphic and traditional linear-slope methods in post-mine reclamation

Abstract

Traditional reclamation consists of landform reconstruction characterized by uniform topography and linear slopes. Geomorphic reclamation improves on traditional reclamation by recreating heterogeneous landforms that blend into surrounding landscapes. Environmental heterogeneity created by geomorphic design is expected to increase the number of available ecological niches, and thus increase plant species diversity when compared with traditional reclamation practices. We sampled plant communities at two reclaimed surface mines in Wyoming using line-point intercept transects to compare vegetative diversity, composition, and structure between sites reclaimed using geomorphic and traditional methods. Greater species richness and Simpson's diversity were observed in geomorphic reclamation at the first site, but did not differ significantly at the second site, although geomorphic reclamation was more likely to resemble undisturbed controls. Shrub abundance was up to 10 times greater on geomorphic reclamation compared to traditional reclamation. Neither reclamation method achieved levels of vegetative diversity observed on nearby, undisturbed rangeland. Geomorphic methods have potential benefits for restoration of vegetative diversity and foundation species such as Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis). Our results suggest geomorphic reclamation may improve plant community diversity and wildlife habitat as a practical method for landscape-level restoration in post-mining sites.