Environmental Factors Affecting Natural Succession On Coal Mine Spoils

Strip-mining for coal and other mineral resources in the southwestern United States has produced problems in reclamation entirely different from those encountered in regions of higher or more effective precipitation. It was the intent of this study to look at the essentially random assortment of environmental factors left after the mining process and to determine qualitatively, as well as quantitatively, which of those factors are more likely to lead to the successful germination and establishment of invading plant species. A second objective was to determine what changes in the spoil material are occurring as a result of plant establishment. Major factors affecting initial invasion and establishment of plant species were found to include topography, slope exposure, degree of surface compaction, and the presence of large rocks on and below the spoil surface. Ecological reactions of established plants include reduced spoil surface temperature extremes, the trapping of wind-blown seed and sand, litter accumulation, and a change in the concentrations of some salts beneath the plant. Sodium ion concentration beneath established four-wing saltbush (Atriplex canescens) increased as a function of depth and distance from the plant while those of potassium decreased. A number of recommendations to improve mine reclamation success are made based on the results of this study.