Scots pine (Pinus sylvestris L.), the suitable pioneer species for afforestation of reclamation sites?

Abstract

As a result of human population growth and human need for resources, the landscape has been increasingly transformed and devastated by mining activities. Subsequent reactivations are thus extremely important in the process of restoring the disturbed biosphere. The objective of this study was to determine differences between original forest sites and reclamation sites afforested with Scots pine (Pinus sylvestris L.) in terms of stand structure, diversity, biomass, productivity and climatic resistance. Three different types of reclamation were compared in the Czech Republic – (1) a post-mining coal site, (2) a former sand quarry and (3) a reclaimed sand dune that had been used for pasture. At the comparable stand age of 40–46 years, the stand volume and biomass were higher by 22% and 19%, respectively, on original forest sites (370–500 m3 ha−1, 332–422 t ha−1) compared to reclamation sites (318–371 m3 ha−1, 287–325 t ha−1). On the contrary, structure and diversity were more complex and richer in reclaimed areas. Climatic factors had a higher effect on radial growth on reclamation sites compared to original forest sites, but no significant differences were observed between the variants in terms of the occurrence of negative pointer years (extreme deflection in growth). A lack of precipitation and long-term droughts in vegetation periods were the main limiting factors of growth. Comparing all reclamation variants, the highest productivity was found on the reclaimed coal-mine, and the lowest differences between forest and reclamation sites were documented in the reclaimed sand quarry case. In relation to climate change, Scots pine proved a very adaptive and suitable tree species whose wood production on reclaimed post-mining sites is comparable to the original forest sites. Pine afforestation of reclamation sites brings invaluable environmental and production benefits.