Evaluation of afforestation development and natural colonization on a reclaimed mine site
Post-mining restoration sites often develop novel ecosystems as soil conditions are completely new and ecosystem assemblage can be spontaneous even on afforested sites. This study presents results from long-term monitoring and evaluation of an afforested oil-shale quarry in Estonia. The study is based on chronosequence data of soil and vegetation and comparisons are made to similar forest site-types used in forest management in Estonia. After site reclamation, soil development lowered pH and increased N, K, and organic C content in soil to levels similar to the common Hepatica forest site-type but P, total C, and pH were more similar to the Calamagrostis forest site-type. Vegetation of the restoration area differed from that on common forest sites; forest stand development was similar to the Hepatica forest-type. A variety of species were present that are representative of dry and wet sites, as well as infertile and fertile sites. It appears that novel ecosystems may be developing on post-mining reclaimed land in Northeast Estonia and may require adaptations to typical forest management regimes that have been based on site-types. Monitoring and evaluation gives an opportunity to plan further management activities on these areas.