Tree invasion on reclaimed anthracite surface mines in Pennsylvania: Reevaluating inhibition Klemow, K.M., R. Klemish, M. Petras, R. Ali, J. Keller, R. Helfrick, T. Tonkin, J. DiGerardo Wilkes University, Wilkes-Barre, PA
Undisturbed sites in eastern North America are forested by a mix of native woody species
Natural revegetation is often limited on mine-impacted sites due to infertile, drought-prone soils, and lack of seed dispersal
To help repair the damage caused by mining, reclamation measures are implemented.
Current reclamation projects follow guidelines of SMCRA (1977), emphasizing regrading land, fertilizing soils, and establishing ground-cover
Site not reclaimed “well” appeared to be rapidly colonized by woody species.
Does reclamation lead to forest development on reclamation sites? • Classic ecological theory based on facilitation model of succession • Early successional stages “prepare site”, paving way for later successional stages. • Inhibition model of succession states that early stages actually inhibit later stages. • Which model aptly depicts process of forest development on reclamation sites?
Wilkes-Barre Pittsburgh Philadelphia General approach • Examine four sites in anthracite area of northeast Pennsylvania. • Three (Ballfield, Newport 4, Cemetery) well reclaimed by BAMR • One (Hanover 12) poorly reclaimed.
Vegetation analysis • 25’ x 25’ plots established in each site • Vegetation quantified in each plot • Percent cover for ground layer • Number of stems for woody species
Findings • Plots having >60% herb cover almost completely lack tree seedlings. • Invasion by clonal species possible on dense sites. • Successful establishment of herb layer may restrict species diversity by excluding species that rely only on seeds for regeneration. • Recruitment by clonal species restricted if source plants not present.
Implications for reclamation strategies: • If reclaimed site is targeted for commercial or residential development, use conventional SMCRA approach. • Important to establish ground cover for erosion control. • If site is likely to remain undeveloped, use ecological restoration approach. • Establish sparser herb cover, allowing colonization by native woody species.
Why should we care? • “Restoration science” now emerging as a new way of thinking, replacing reclamation-based approach (see SER 2002) • Benefits of reclamation leading to natural forest ecosystems: • Higher sustainability • Higher biodiversity • Carbon sequestration • Watershed-wide benefits
Incorporate GIS-based technologies to recommend reclamation approach, based on likelihood for site development. www.units.ohio-state.edu www.esri.sc.edu And the next step:
Acknowledgements • Financial and logistical support provided by Wilkes University • Site access provided by Earth Conservancy & PA BAMR • Helpful discussions with colleagues • Dale Bruns, Bill Toothill (Wilkes University) • Robert Hughes (Eastern PA Coalition for Abandoned Mine Reclamation)