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.

Hard rock overburden is often used as a topsoil substitute for reclamation in the southern Appalachian surface mining region because of the limited availability of natural topsoil. In relatively unweathered overburden materials, soil‐forming processes are accelerated and the resulting mine soils form rapidly. Morphological, physical, and chemical properties related to overburden weathering in mine soils formed from siltstone and sandstone overburden were observed for 6 to 8 yr. Distinct surface soil horizons, enriched with organic matter, occurred within two growing seasons after mine soil construction, and discernible subsurface horizonation developed within four growing seasons. The degree of development of surface and subsurface soil horizons became more pronounced after 8 yr. Coarse fragment content of sandstone‐derived mine soils decreased, and silt content of siltstone‐containing mine soils increased during six growing seasons. Although pH and extractable Ca and Mg levels decreased during the first three growing seasons, apparently due to rapid leaching of exposed carbonates, these properties rebounded to near initial levels after six growing seasons due to release of Ca and Mg from continued carbonate weathering and phytocycling. Levels of extractable Fe tripled between the first and second growing seasons and then remained relatively constant for the rest of the study. The changes in soil properties in these mine soils indicated that geochemical weathering and oxidation was occurring rapidly. This study demonstrated the complexity of mine soil weathering and development processes and the difficulties involved in predicting all eventual mine soil properties from premining overburden analysis.

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This study presents a description of aerobic capacity in a large US population comprised of 1,514 men and 375 women. Such influencing factors as age, training state, occupation, and body composition were evaluated. The population consisted of new recruits entering the US Army from civilian life as well as soliders in a variety of assignments and physical training programs. Age ranged from 17 to 55 yr. With the exception of one older group, aerobic capacity was determined as maximal O2 uptake measured directly by the Douglas bag technique during a standard discontinuous treadmill running procedure. New male and female recruits representing a young civilian population entered the service with maximal O2 uptake of 51 and 37 ml X kg body wt-1 X min-1, respectively, and thereafter increased 5% during initial basic training. The difference between genders, 30% on an absolute basis, was 14% when expressed as a function of fat-free weight. Aerobic capacity was less after occupational training and continued to decrease with age at an average yearly rate of 10%, or 0.5 ml X kg body wt-1 X min-1. Aerobic capacity varied with intensity of the occupational physical demand, except in groups with significant physical training programs. This first large US population study of aerobic capacity, using a direct treadmill procedure, demonstrates levels consistent with any previously reported population.