Growth of willow energy plantations on the marginal lands of the Kyiv Polissia
Purpose. Investigation of the features of growth, development and productivity of energy willow varieties on peat-bog and alluvial sandy soils in the floodplains of the Kyiv Polissia rivers. Methods. Field, laboratory, analytical, and statistical. Results. It is advisable to use the variety ‘Zbruch’, to create willow energy plantations on the peat-swampy soils of the Kyiv Polissia. It is characterized by the highest yield of three-year biomass (9.84 t/ha), while in the ‘Ternopil’ cultivar the maximum was 3.29 t/ha and in the Salix triandra clone 2.68 t/ha. On alluvial sandy soil, the highest average height (194 ± 6.6 cm), with a productivity of two-year biomass of 3.15 t/ha had Swedish variety ‘Tordis’. In addition, relatively high productivity have Polish varietyes ‘082’ and ‘1047’ and the domestic variety ‘Ternopil’. The productivity of the latter after two years of growth on the sandy soil is 1.53–6.41 t/ha, and after three years on the peat soil only 1.74–3.29 t/ha. To increase the productivity of energy plantations of willow on fresh alluvial sandy soils, it is advisable to apply organic and mineral fertilizers, and on peat soils to apply deep plowing, to conduct proper control over the number of weeds, to use the density of planting cuttings about 20 000 plants ha and a 4-year biomass harvest cycle. Conclusions. It is established that in alluvial soils of floodplains of Kyiv Polissia rivers, fresh alluvial soils are more suitable for growing willow energy plantations than rich on organic substances moist peat-bog soils. ‘Tordis’, ‘082’, ‘1047’ and ‘Ternopil’ varieties are promising for growing on the sandy soils of the study area, and ‘Zbruch’ for peat soils. Considering the low fertility of the studied variants of marginal lands, in order to increase the efficiency of cultivation of energy biomass of willow on them, first of all, it is necessary to improve the water-physical properties of soils.