Forest Productivity aud Minesoil Development Under A White Pine Plantation Versus Natural Vegetation After 30 Years

Abstract

In 2000, the State of West Virginia passed legislation requiring commercial forest land as a preferred post-mining land use on surface coal mines, and especially on those sites where mountaintop removal mining is occurring and valley fills are being constructed. Due to West Virginia's mountainous terrain, most future surface mine permits will be impacted by this change in post-mining land use. Therefore, interest has been renewed into studies examining forest productivity and minesoil development on areas planted in trees. Since fresh geologic materials in minesoils undergo rapid pedogenic changes, long-term studies may provide valuable insight into tree growth, plant succession al changes, and soil development over time. In summer of 2000, soil development and forest productivity were evaluated on a 30-year-old (pre-SMCRA) surface mine in northern West Virginia that had been planted with white pine (Pinus strobus L.). The site offered a unique research opportunity in that one-half of the site was planted to white pine, while the other half was left to natural revegetation. Canopy tree species composition, density, basal area, and height, along with species composition and density of woody understory seedlings, were evaluated in the pine plantation and on the naturally revegetated site. On each site, three soil pits were dug, the minesoils were classified, and soil samples were taken from each described horizon to determine physical .and chemical properties. Forest productivity, including productivity of volunteer hardwoods, was much greater on the pine planted site than on the naturally revegetated site. Species composition of woody regeneration in the understory showed that both sites will revert to mixed hardwoods similar to the surrounding forest via natural succession. Minesoils on both sites experienced rapid soil development during the 30-year post-mining period. All six minesoil profiles had well developed Bw horizons and would have been classified as Inceptisols. Minesoil development was better on the naturally revegetated site possibly due to the difference in ground cover type. Additional Key Words: Minesoil Properties, Reforestation, Revegetation, Tree Planting, Introduction Surface coal mining disturbed approximately 1.5 millionha(3.7millionac)between 1930and 1971 in the United States (Paone et al. 1978). In Appalachia, the vast majority of surface mined land was originally forest land Laws were passed in Ohio, Pennsylvania, and West Ziemkiewicz is Director, West Virginia University, Morgantown WV 26506. Virginia during the late 1930s and 1940s requiring mine operators to register with the state and pay bonds to ensure reclamation after mining. Reclamation prescribed in these early laws directed soil, subsoil, and overburden (the geologic material overlying the coal) be used to refill the excavated area. Backfilling and leveling the land was specified, and then trees and shrubs were to be planted in the regraded areas.Studies of surfaceminerevegetation with trees began in the 1920s and repor...

Vegetation and soil development in planted pine and naturally regenerated hardwood stands 48 years after mining

“…Skousen et al (1994) also reported rapid reforestation of naturally revegetated sites in West Virginia. Our finding that naturally regenerated hardwood stands had a higher basal area than planted pine is contrary to results of Gorman et al (2001) who observed higher forest productivity in planted pine sites in comparison with natural succession after 30 years. However, an assessment of well-stocked forest stands on older coal mine spoils of the eastern and mid-western U.S. showed that planting of pine during reclamation can either increase or decrease forest productivity, depending on the suitability of the pine species to the site (Rodrigue and Burger, 2002), with a maximum productivity of pine at 30-40 years, while hardwood stands matured at 60-80 years.…”

“…Areas that had been planted with any pine species, and still contained pine, were designated as "pine." On these areas the natural succession of pine to hardwood (Gorman et al, 2001) had been hastened by an outbreak of Southern pine beetle (Dendroctonus frontalis) around 1996, leaving numerous gaps. Therefore plots were selected to minimize the effect of gaps and capture the long-term effects of planted pine.…”

Selecting Topsoil Substitutes for Forestry Mine Soils

“…1-3). This good tree growth was attributed to the random placement of weathered overburden at the surface (overburden selection and placement were not planned or regulated), little or no surface grading to compact the soils, and little or no seeding of grass for revegetation (Ashby, 2006;Gorman et al, 2001). Because the older surface mines were smaller and often disturbed only near-surface rock, weathered overburden materials often comprised the majority of overburden and was placed on the surface loosely, with minimal or no grading.…”

“…This differential weathering among rock types influences the rate of soil genesis and the future productivity potential of the soil (Gorman et al, 2001;Haering et al, 1993;Johnson and Skousen, 1995;Torbert et al, 1988). Figure 4.…”

Comparison of international mine reclamation bonding systems with recommendations for China

“…As government regulations progressed, mining companies were required to backfill the area and plant grasses or trees (Gorman et al 2001;Skousen et al 2006). During the ensuing 30 years, more requirements were instituted to promote reclamation and some states had more stringent laws and regulations, and some had a reclamation bond.…”