Purpose. To determine the parameters of the main factors affecting the productivity of energy plantations of willow on the floodplain soils of Polissya (Ukraine).Methods. The experimet with energy willow plantations were created using annual cuttings of the varieties ‘Zbruch’, ‘Ternopilska’ and a Salix triandra willow clone, planted in double rows with a distance of 0.75 m between them and with a row spacing of 1.5 m. Planting cuttings density: 10, 15 and 20 thousand pcs/ha.Results. After the first growing season in the 'Ternopilska' variety, the survival rate of cuttings on peat-bog soil ranged from 48.6 to 54.8 %, in the 'Zbruch' variety from 72.8 to 86.6 %, and in Salix triandra from 71.0 to 82.3 %. During the second growing season there was a significant decline in plants, especially in denser stands. On sandy soil, after the second year of vegetation, from 74.1 to 87.5 % of plants remained. Biomass productivity in the first 3 years on peat-bog soil was 0.58–1.10 t/ha/year in ‘Ternopilska’ variety, 0.80 to 3.28 t/ha/year in ‘Zbruch’ variety, and from 0.62 to 0.96 t/ha/year. At the same time, the density of plantations and edaphic conditions significantly affected the productivity of the dry mass of plants. In particular, on sandy loam soil, 'Ternopilska' variety in the first 2 years had productivity from 0.77 to 3.21 t/ha/year, which is significantly higher than on rich of organic substainces moistened peat-bog soils. The largest leaf area was in 'Ternopilska' variety on sandy loam soil, from 22.0 to 31.3 thousand m2/ha, and in 'Zbruch' variety (from 17.2 to 27.5 thousand m2/ha). The average photosynthetic potential according to the experimental options ranged from 1.67 to 5.06 million m2·day/ha, increasing with increasing planting density and leaf area. The highest net productivity of photosynthesis indicators are observed in 'Ternopilska' variety on sandy soil, from 0.98 to 1.62 g/m2 per day and in ‘Zbruch’ variety (0.70–1.16 g/m2 per day). At the same time, these indicators were maximum with a density of 15 thousand plants./ha.Conclusions. In floodplains of the Polissia, sandy loamy soils are more suitable for growing the willow energy biomass compared to peat-bog soils. Willow energy plantations have a large leaf surface area, high photosynthetic potential and net photosynthesis productivity, which provides relatively high biomass productivity indicators. On peat-bog soils from the studied varieties, it is advisable to use ‘Zbruch’ variety, which is characterized by high biomass productivity (3.28 t/ha/year), to create willow energy plantations.
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