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Surface coal mining in Appalachia has caused extensive replacement of forest with non-forested land cover, much of which is unmanaged and unproductive. Although forested ecosystems are valued by society for both marketable products and ecosystem services, forests have not been restored on most Appalachian mined lands because traditional reclamation practices, encouraged by regulatory policies, created conditions poorly suited for reforestation. Reclamation scientists have studied productive forests growing on older mine sites, established forest vegetation experimentally on recent mines, and identified mine reclamation practices that encourage forest vegetation re-establishment. Based on these findings, they developed a Forestry Reclamation Approach (FRA) that can be employed by coal mining firms to restore forest vegetation. Scientists and mine regulators, working collaboratively, have communicated the FRA to the coal industry and to regulatory enforcement personnel. Today, the FRA is used routinely by many coal mining firms, and thousands of mined hectares have been reclaimed to restore productive mine soils and planted with native forest trees. Reclamation of coal mines using the FRA is expected to restore these lands' capabilities to provide forest-based ecosystem services, such as wood production, atmospheric carbon sequestration, wildlife habitat, watershed protection, and water quality protection to a greater extent than conventional reclamation practices.

Natural topsoils in the Appalachian surface mining region are often more difficult to use and less desirable than alternative spoil materials. Parent material effects and initial pedogenic changes over 3 yr were observed in 5 mixes of sandstone (SS) and siltstone (SiS) spoils under grass vegetation. Spoil type controlled initial soil texture, but significant decreases in sand contents and increases in silt contents occurred in several spoil mixes within 2 yr. All mine soils studied were high (≥65%) in coarse fragments. Mine soils derived from spoils high in siltstone content were higher in coarse fragments, pH, extractable cations and iron, fine earth (<2 mm) water holding capacity, and electrical conductivity than sandstone mine soils. Dissolution and leaching, oxidation, and organic matter incorporation were dominant pedogenic processes influencing mine soil properties over the period of this experiment. Distinct surface A horizons formed within 3 yr. Water retention in the <2‐mm fraction increased over time in the surface (0 to 5 cm) of all spoil types except pure sandstone. Extractable Fe and total N increased between 1982 and 1984, while pH, and extractable Ca, Mg and P decreased in most spoil types. These changes reflect rapid pedogenesis in fresh unweathered parent materials in a humid environment.

Soil quality research has focused on intensively managed agricultural and forest soils, but the concept and importance of soil quality is also pertinent to reclaimed mine soils and other disturbed ecosystems. Adding organic amendments has been used as a means for ameliorating mine soils and improving their quality, but the long‐term effects of amendments on soil quality are not known. In 1982, a mined site was amended with seven different surface treatments: a control (nothing added), 30 cm of native soil, 112 Mg ha−1 sawdust, and municipal sewage sludge (SS) at rates of 22, 56, 112, and 224 Mg ha−1 Four replicates of each treatment were installed as a randomized complete block design. Each plot was split and planted with pitch × loblolly pine hybrid (Pinus rigida × taeda) trees and Kentucky‐31 tall fescue (Festuca arundinacea Schreb.). During the 16‐yr period, organic matter content, total organic N, N mineralization potential, aggregate stability, and other physical and chemical properties were measured as mine soil quality indicators. The comparative ability of these organic amendments to positively affect organic matter content, total N, and other parameters was most apparent and pronounced after 5 yr. However, after 16 yr, soil organic matter (SOM) content and total N appeared to be equilibrating at ≈10 000 and 750 kg ha−1, respectively. Organic matter inputs by vegetation alone across the 16‐yr period in the control plots resulted in organic matter and N mineralization potential values comparable to levels in the organically‐amended plots, indicating the overriding importance of vegetation in the soil recovery process. After 16 yr, there appears to be no lasting soil quality improvements due to addition of organic amendments to this mine soil. Amendments improved short‐term production, but their cost of transport and application may be difficult to justify based on long‐term soil quality improvement.

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