Christopher D. Barton

Restoring Forests and Associated Ecosystem Services on Appalachian Coal Surface Mines

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.

Structural and functional characteristics of natural and constructed channels draining a reclaimed mountaintop removal and valley fill coal mine

Abstract Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the USA. Among the changes are large-scale topographic recontouring, burial of headwater streams, and degradation of downstream water quality. The goals of our study were to: 1) compare the structure and function of natural and constructed stream channels in forested and MTR/VF catchments across ephemeral, intermittent, and perennial flow regimes and 2) assess the relationship between leaf litter breakdown and structural measures, such as the habitat assessments currently used by regulatory agencies. Specific conductance of stream water was, on average, 36 to 57× higher at perennial reaches below valley fills than at perennial reaches in forested catchments, whereas pH was circumneutral in both catchment types. Channel habitat and invertebrate assemblages in litter bags differed between forested streams and constructed channels in VF catchments. Invertebrate density, diversity, and biomass were typically higher in litter bags from forested catchments than from VF catchments. No differences in fungal biomass, estimated as ergosterol concentration, were detected between litter bags from forested and VF catchments. Breakdown of oak (Quercus alba) leaves was slower at perennial and intermittent reaches in VF catchments than at perennial and intermittent reaches in forested catchments. However, breakdown rates did not differ between ephemeral reaches on VFs and in forested catchments. Breakdown rates of oak leaves were significantly correlated to conductivity at perennial and intermittent reaches and to shredder diversity across all reaches, but were not correlated with habitat assessment scores currently being used to determine compensatory mitigation. Landuse changes associated with MTR/VF have detrimental consequences to headwater stream function that are not adequately evaluated using the prevalent habitat assessment.

Water quality characteristics of discharge from reforested loose-dumped mine spoil in eastern Kentucky.

Surface mining is a common method for extracting coal in the coal fields of eastern Kentucky. Using the Forestry Reclamation Approach (FRA), which emphasizes the use of minimally compacted or loose-dumped spoil as a growth medium for trees, reclamation practitioners are successfully reestablishing forests. Yet, questions remain regarding the effects FRA has on the quality of waters discharged to receiving streams. To examine the effect of FRA on water quality, this study compared waters that were discharged from three types of spoils: predominantly brown, weathered sandstone (BROWN); predominantly gray, unweathered sandstone (GRAY); and an equal mixture of both aforementioned sandstones and shale (MIXED). The water quality parameters pH, EC, Ca, K, Mg, Na, NO-N, NH-N, SO, Cl, TC, suspended sediment concentration (SSC), settleable solids (SS), and turbidity were monitored over a 2-yr period on six 0.4-ha plots (two replications per spoil type). Generally, levels of Cl, SO, Ca, NO-N, NH-N, SS, SSC, and turbidity decreased over time. The pH for all spoils increased from about 7.5 to 8.5. The EC remained relatively level in the BROWN spoil, whereas the GRAY and MIXED spoils had downward trajectories that were approaching 500 μS cm. The value of 500 μS cm has been reported as the apparent threshold at which certain taxa such as Ephemeroptera (e.g., Mayfly) recolonize disturbed headwater streams of eastern Kentucky and adjacent coal-producing Appalachian states.

Runoff curve numbers for loose-dumped spoil in the Cumberland Plateau of eastern Kentucky

Excess compaction occurs through the use of traditional surface mining reclamation techniques, resulting in low infiltration rates and subsequently high peak flows and runoff volumes. The incorporation of loose-dumped spoil into the reclamation process has been shown to promote tree growth; however, designers have little information regarding the probable hydrologic consequences (PHC) associated with this spoil disposal method. To better understand the hydrologic effects of reclaiming mined lands using loose-dumped spoil, curve numbers (CN) were developed for both a steeply sloping, forested watershed in eastern Kentucky and six, 0.4 ha test cells comprised of three types of loose-dumped spoil: (1) brown, weathered sandstone, (2) grey, unweathered sandstone and (3) a mixture of both sandstones and shale. The spoil was placed in accordance with the Forestry Reclamation Approach (FRA). Results of this project indicate that the mean CN for loose-dumped spoil was equivalent to the mean CN for the forested watershed.

FOREST ESTABLISHMENT AND WATER QUALITY CHARACTERISTICS AS INFLUENCED BY SPOIL TYPE ON A LOOSE- GRADED SURFACE MINE IN EASTERN KENTUCKY

Six research plots were established on a surface mine for the purpose of evaluating the forest productivity potential and hydrological and water quality characteristics of three different loose-graded spoil types. The three spoil types were: (1) predominately brown, weathered sandstone (BROWN); (2) predominately gray, un-weathered sandstone (GRAY); and (3) mixed weathered and un-weathered sandstones and shale material (MIXED). The average area of the six plots was approximately 3,658 m 2 . The physical and chemical soil characteristics that gave the BROWN spoil type a predictably higher productivity potential and natural regeneration than the GRAY and MIXED spoil were its finer soil texture, higher CEC and P concentration, and a pH that was more suitable for native hardwood trees. Four species of tree seedlings were planted into the spoils. Growth and survival of the planted trees were evaluated for three years. As an indicator of natural succession potential, percentage ground cover of volunteer vegetation on the three spoil types was also evaluated. By the third year (2007) after planting, the BROWN spoil type had a significantly higher average tree volume index than the MIXED spoil and MIXED was significantly higher than GRAY. Ground cover from natural regeneration was found to be 66.4% on the BROWN spoil (61 different species), 5.8% on the MIXED spoil (35 different species), and less than 2.0% on the GRAY spoil (12 different species). Results showed that the loose-graded spoil in this experiment was characterized by low discharge volumes, small peak discharges, and long durations of discharge and had hydrologic characteristics of a forested watershed, even at this early stage of development. Generally, concentrations of Ca, Mg, and SO4 2- decreased over time in GRAY and MIXED and increased in BROWN. The pH of the water discharge from all three spoil types has increased from about 7.5 to 8.5. Although the average electrical conductivity (EC) in water discharged from the BROWN spoil remained relatively level during the study period, the GRAY and MIXED appears to be on a downward trajectory from about 1500 µS cm -1 to about 500 µS cm -1 . The latter value of EC has been reported as the apparent threshold at which the benthic invertebrate community returns to drastically disturbed headwater streams of eastern Kentucky and adjacent coal-producing Appalachian states.

SURFACE MINE REFORESTATION RESEARCH: EVALUATION OF TREE RESPONSE TO LOW COMPACTION RECLAMATION TECHNIQUES 1

In 1996, a multidisciplinary group of researchers at the University of Kentucky initiated a study on the Starfire surface mine in eastern Kentucky to evaluate the effects of soil compaction and two organic amendments on the survivability and growth of high value tree species. Three types of prepared rooting medium were examined: compacted spoil, lightly compacted spoil, and uncompacted spoil. The compacted spoil was prepared using normally accepted spoil handling techniques that resulted in a smooth graded surface. The lightly compacted spoil was loose-dumped and struck-off with one or two passes of a bulldozer. The uncompacted spoil was loose-dumped and not further disturbed. In addition, organic amendments (mulches) were evaluated within the three reclamation techniques. The organic amendments used were processed hardwood bark mulch and a combination of straw and horse manure mulch. The following six species of trees were planted: white oak (Quercus alba), white ash (Fraxinus americana), eastern white pine (Pinus strobus), northern red oak (Quercus rubra), black walnut (Juglans nigra), and yellow poplar (Liriodendron tulipifera). Five of the six species, the exception being white ash, showed increased survivability as compaction was minimized. Additionally, the loose-graded techniques led to enhanced growth in height for the seedlings. The addition of organic amendments also showed additional benefit but results varied by species and by treatment. Results definitively show that strike-off and loose-dump techniques improve seedling height and survival. The data also suggest that even a small amount of traffic (i.e., one or two passes per the strike-off method) may result in enough compaction to significantly reduce survival and growth in some species, such as yellow poplar and white pine. In the backfilling and grading process, spoil material should be placed and compacted according to standard engineering practices so that the required stability and approximate original contour is achieved. However, the top 1.2 to 1.8 meters (4 to 6 feet) of material should not be graded or only lightly graded so that it is as uncompacted as possible.

Ecological outcomes and evaluation of success in passively restored Southeastern depressional wetlands

Depressional wetlands may be restored passively by disrupting prior drainage to recover original hydrology and relying on natural revegetation. Restored hydrology selects for wetland vegetation; however, depression geomorphology constrains the achievable hydroperiod, and plant communities are influenced by hydroperiod and available species pools. Such constraints can complicate assessments of restoration success. Sixteen drained depressions in South Carolina, USA, were restored experimentally by forest clearing and ditch plugging for potential crediting to a mitigation bank. Depressions were assigned to alternate revegetation methods representing desired targets of herbaceous and wet-forest communities. After five years, restoration progress and revegetation methods were evaluated. Restored hydroperiods differed among wetlands, but all sites developed diverse vegetation of native wetland species. Vegetation traits were influenced by hydroperiod and the effects of early drought, rather than by revegetation method. For mitigation banking, individual wetlands were assessed for improvement from pre-restoration condition and similarity to assigned reference type. Most wetlands met goals to increase hydroperiod, herb-species dominance, and wetland-plant composition. Fewer wetlands achieved equivalence to reference types because some vegetation targets were incompatible with depression hydroperiods and improbable without intensive management. The results illustrated a paradox in judging success when vegetation goals may be unsuited to system constraints.

Small Mammal Response to Vegetation and Spoil Conditions on a Reclaimed Surface Mine in Eastern Kentucky

Abstract Ecologically effective mine reclamation is characterized by the return of pre-mining floral and faunal communities. Excessive soil compaction typically results in delayed succession and low species diversity on reclaimed mine lands. We compared small mammal abundance and diversity among three levels of compaction in reforestation plots on an eastern Kentucky surface mine during 2004 and 2005. Compaction levels included 1) no compaction (loose-dumped), 2) light compaction (strike-off), and 3) high compaction (standard reclamation). Peromyscus leucopus (White-footed Mouse) made up 98% (295 of 300) of all individuals captured. In 2004, loose-dumped plots had more White-footed Mice (n = 108, mean = 36, SE = 0.58) than high-compaction plots (n = 62, mean = 20.6, SE = 3.10). Strike-off plots had more White-footed Mice (n = 59; mean = 19.6, SE = 0.66) than loose-dumped (n = 46, mean = 15.3, SE = 1.45) or high-compaction (n = 20, mean = 6.6, SE = 2.19) plots in 2005. Canopy cover and large rocks that created crevices appear to have been the factors that most influenced White-footed Mouse abundance on our study sites. Low small-mammal species diversity across all treatments was likely due to the presence of low quality habitat resulting from a poorly developed ground layer and soil compared to that found in undisturbed forest. Additionally, an insufficient amount of time since reclamation for small-mammal colonization from surrounding forests and a relatively large matrix of non-forested reclaimed mineland between our plots and potential source habitats may have also limited small-mammal diversity. To promote biodiversity and provide better wildlife habitat, we suggest that mine operators consider using reclamation methods that promote surface and vegetation heterogeneity and connectivity to source habitats.

Influence of tree shelters on seedling success in an afforested riparian zone

The restoration of a natural riparian ecosystem is a key component to improving water quality and restoring stream health in a disturbed watershed. The rate and degree of riparian restoration, and hence stream restoration, depends in part upon afforestation practices. Successful afforestation is determined largely by the rates of survivorship and growth of the tree species planted or recruited in a riparian zone. This study was part of a project involving the restoration of a channelized section of Wilson Creek located in the Bernheim Arboretum and Research Forest, Nelson County, Kentucky. Riparian restoration activities focused on reestablishing a native riparian corridor using American sycamore (Platanus occidentalis), green ash (Fraxinuspennsylvanica var. subintegerrima), and pin oak (Quercus palustris). This study evaluated techniques for improving the growth and survivorship of planted seedlings along Wilson Creek. Specifically, two tree shelter types (Tubex® vs. continental mesh), with or without herbicide treatments, were compared. Additionally, the influence of these techniques on debris retention within the riparian zone was also examined. Results showed that use of tree shelters significantly increased the growth of seedlings (but not survivorship), provided physical protection especially during heavy flooding events, and accelerated woody debris retention. Both Tubex® and continental mesh tree shelters were effective in enhancing seedling growth, with Tubex® shelters yielding significantly better growth when combined with herbicide to control competing vegetation. Thus, the most cost effective choice may depend on the environmental setting and ability to combine the shelters with other growth enhancing treatments.

THE FORESTRY RECLAMATION APPROACH AND THE MEASURE OF ITS SUCCESS IN APPALACHIA 1

The Appalachian Regional Reforestation Initiative (ARRI) is a broad- based citizen/industry/government program working to encourage the planting of productive trees on abandoned and active coal mine lands. Forestry research has confirmed that highly productive forestland can be created on reclaimed mine land by using a five step straight-forward methodology called the Forestry Reclamation Approach (FRA). Data taken from Office of Surface Mining and state regulatory permit and bond release documents indicate that since the start of ARRI in 2005, a gradual increase in the planting of trees on coal surface mines has occurred. ARRI states reported about 9.4 million trees planted in 2005, 11.1 million trees planted in 2006, and 12.8 million trees planted in 2007. However, despite an aggressive technical outreach by ARRI, serious cultural barriers and other impediments to proper surface mine reforestation remain pervasive in the Appalachian coalfields. In 2007, the ARRI states reported that of the 12.8 million trees planted, only 3.4 million trees were planted using the full 5 steps of the FRA. The number of trees planted on conventionally reclaimed sites which were not FRA compliant was estimated at 9.4 million. One or more of the 5 steps of the FRA where not utilized on over two-thirds of the trees planted on surface mines in Appalachia over the past three years.