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Productivity of Pine Plantations during Reclamation of Sand Quarries

Restoration of lands disturbed by anthropogenic impact is currently the most urgent issue in the light of the gradually decreasing area of commercially valuable plantations. Reclamation of quarries includes restoration of artificial landscape by carrying out various kinds of measures. We have surveyed the quarries located in the northern districts of the Arkhangelsk region. These quarries were used for sand mining in the construction of roads of federal and regional importance. No forestry activities were carried out in one of the quarries. It was adopted as a control site and abandoned to natural regrowth. Deciduous trees and shrubs (birch, willow) in some places grow there after a decade and a half. In two other surveyed quarries mechanical soil treatment was carried out and seedlings of Scots pine (Pinus sylvestris L.) were planted. This species is used for planting on sandy soils to form valuable productive stands. Studies have shown that pine young stands of the second age class have quality class II, with the average forest inventory values of a diameter of 14.6 cm, a height of 15.6 m and a stock of 168 m3/ha. The plants are healthy, physiologically developed with the average annual increment of 56 cm over the last decade. Forestry measures effectively carried out in the development of sand quarries, firstly, provide the necessary optimal conditions for growth and development of plants, and, secondly, biologically productive areas of the land surface are formed due to forest reclamation. These territories are an excellent reserve for increasing the areas covered by forest vegetation.