Post-mining peaty lands were formed as a result of peat extraction on drainage wetlands areas. After peat extraction has finished, the biggest problem is to use these lands for other purposes. This type of soil is very heterogenic, poorly drained, with massive structure and poor contents of nutrients. Thus it is very problematic to grow traditional agricultural crops that have special requirements for soil fertility on those areas. The area of post-mining peaty lands in Belarus alone is about 200 000 hectares. One of the perspective directions of post-mining peaty land use is re-wetting and production of biomass for energy purposes. The goal of our research was to estimate cost of biomass of natural grass and willow wood from short rotation coppice (SRC) plantations which may be used as feedstock for pellet production. The dominant wetland species were common reed, cattail and sedges. SRC plantation was planted on degraded soils. The prime cost of biomass which was produced on the base of natural grass was from 10.4 euro per ton to 13.2 euro per ton, depending on technology. The prime cost of willow biomass was 24.1 euro per ton. Introduction of taxes will increase cost of biomass by approximately 60 %. The calculation of economic efficiency identified that biomass as a feedstock for pellet production on post-peat mining areas may be a profitable direction for peat factory function and providing the sustainable development of local communities. Additional profit may be obtained as a result of saving carbon quotas. The share of CO2 emissions from fossil fuel for grass biomass production is about 2 % from the total volume of CO2 during renewable biomass utilization for energy and for chips production from willow wood - 6 %. The diversification of biomass sources enables to use feedstock for a pellet line in the winter and spring which is in the heating season.

Alternative or renewable energy is a modern strategy with a good per?spective in the nearest future. There are several directions of renewable energy development that depend on climatic, economic and technological opportunities of a region. The perspective choice for areas with moderate climate is bioenergy. One of the bioenergy directions is agro forestry based on short rotation coppice plantations (SRC) of trees, like willow, poplar and others. The goal of experiments was the assessment of the potential of different willow species for the obtaining of energy in two climatic zones and on two types of soils of Belarus. For this purpose several morphological characteristics were metered: height of plants, biomass, diameter and number of sprouts. The field experiments were conducted on two types of soils: post-mining peaty soils in Grodno region and on degraded peaty soils in Brest region of Belarus. The same soils are very problematic for growing of traditional agricultural crops, thus willow production is a good alternative for biomass production of energy as well as for the reclamation of these soils. In our experiments the following species of willow were tested (Salix alba, Salix viminalis, Salix dasyclados, Salix aurita) that may grow on peaty soils at the natural conditions. The most popular species for modern selection of SRC of willow is Salix viminalis. Nevertheless, the most suitable morphological characteristics on post-mining peaty soils were established for plants of Salix dasyclados and on degraded peaty soils for the plants of Salix alba. The unfavorable parameters at the both type of soils were identified for the plants of Salix aurita. However, it is necessary to take into account that the used species are more popular for natural wetlands and in our experiments plants have best results of survival of cutting and rates of growth at the beginning of vegetation. In accordance with these facts Salix aurita may not be used for energy plantation directly, but it is interesting for hybridization with other species. Our results have shown that perspective hybrids for peaty soils may be for instance Salix aurita x Salix dasyclados and Salix aurita x Salix alba.

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Willow is a low-maintenance crop that has potential for energy production and enhancing the local environment. The area of commercial plantations of willow in Europe is mostly concentrated in Sweden, with more than 20 000 ha. Willow trees are used not only for energy production, but also for reclamation of polluted soils because a plantation may grow for 20–25 years, with a three-year period of harvesting. Our research covers issues of reclamation of soils contaminated by radionuclides and heavy metals, and decreasing of eutrophication of water ecosystems with using willow plantations. The field studies of phytoremediation of soil contaminated by 137Cs by willow plants were conducted in eastern Belarus, in the area where agricultural activity was banned after Chernobyl disaster. This region is heavily polluted with 137Cs (from 185 to 555 kBq/m2) and heavy metals. The transferring factors of accumulated 137Cs and heavy metals from the soil to willow biomass were determined. The field experiments showed that willow does not accumulate actively Cd and Pb, but it accumulates Zn, Cu and Mn intensively. The potassium application decreases the accumulation of 137Cs in willow biomass and increases accumulation of Cu, Zn and Mn, but has no influence on accumulation of Cd and Pb. Our results confirmed that soils polluted with radionuclide and heavy metals could be used for willow cultivation as energy crop, if adequate management is applied. The different potential of the willow species concerning heavy metals accumulation was also established. The yield of willow biomass on polluted soils achieved 11.5–12.8 DMg ha–1 per year, depending on variety, that is competitive with the ordinary yield of willow on mineral fertile soils. Willow plantations also may be used for accumulations of nutrients like nitrogen and phosphorus in watersheds. It enables to decrease impact for water ecosystems and to control eutrophication.

The goal of investigation was assessment of environmental impact and economic efficiency of composite briquette production on the base of peat and renewable biomass. Biomass for composite briquettes was obtained from straw (cereal crops and rape) and wood residues (sawdust, chips) Experimental composite briquette were produced from the mixture of peat and biomass in relation to – 25 : 75, 50 : 50, 75 : 25. The technological cards of biomass feedstock production for 6 variants were developed. Technological cards were used for calculation of emission into the atmosphere during life cycle of biomass production and prime cost of biomass. The lowest volume of gas (SO2, NOx, CO2) and particulate matter (PM) emission was installed for biomass production from the sawdust. The highest volume of emission was installed for production of biomass from the straw with pressing it in standard bale. The volume of CO2 emission for the sawdust production was 6 kg per ton of biomass and for the standard bale of straw was 19 kg per ton of biomass. Prime cost of sawdust production (lowest) was 11 belarusian rubles per ton of biomass, for the wood chips was 19 rubles per ton and for the straw varied from 26 to 33 rubles per ton in depend of technology. It was installed that growth of biomass rate in composite briquette had a good influence on number of basic fuel characteristics (contents of ash, sulfur and moisture). The variation of calorific value of briquette was not significant in depend of biomass contents. In accordance with assessment of all characteristics the better briquettes was obtained from the peat and sawdust.