INFLUENCE OF SHELTERBELTS OF DIFFERENT DESIGNS ON SOIL FERTILITY AND MOISTURE AVAILABILITY IN THE RIGHT-BANK FOREST-STEPPE

Abstract

During 2020-2023, the authors studied nutrient reserves, namely the content of humus, mobile nitrogen, phosphorus and potassium, as well as the level of acidity in the soil layers of 0-20 and 20-50 cm in openwork-blowing, openwork, dense forest strips, determined the reserves of total and available moisture, the dynamics of productive moisture and moisture availability during the growing season in individual collective farms in the Uman district of Cherkasy region. Studies have shown that the humus content in forest strips of various designs ranges from 2.5 to 3.6%. That is, the humus content is low. The highest amount of humus was found in the openwork design of the forest belt. The pH level in the 0-20 cm soil layer ranges from 5.87 in the openwork-blown forest belt to 7.3 units in the dense one. The highest NO3 content is observed in the 20-50 cm soil layer in the openwork forest belt - 141.4 mg/kg. The P2O5 content in the lower soil layer ranges from 62.1 mg/kg to 142.0 mg/kg. The highest P2O5 content of 168.0 mg/kg was found in the 0-20 cm soil layer of the openwork-blow forest belt. The amount of K2O in the upper soil layer is the same for all variants, in the lower layer it varies from 73.3 to 91.0 mg/kg. The openwork-blown forest belt has an available moisture reserve of 44.88 mm, the openwork belt - 51.03 mm, and the dense belt - 67.24 mm, which, compared to the dense forest belt, the moisture content of the openwork-blown belt is 33.27% lower and that of the openwork belt is 24.11% lower. Investigating the dynamics of changes in moisture productivity and moisture availability during the growing season (May-October) in all variants of the experiment both in 0-20 cm and 0-50 cm soil layer, a significant decrease in these indicators is observed. Thus, in the openwork-blown forest strip in the 0-20 cm soil layer in May, from 68 mm and 78%, these indicators decreased in October to 17 mm and 18%, respectively, i.e., in terms of moisture productivity by 4 times and moisture availability by 4.3 times. This indicates that the productivity and moisture content of the experimental forest strips are much higher compared to the control (open field), where the moisture productivity is 42 mm and the moisture availability is 35%. At a depth of up to 50 cm, the soil moisture content in the blown forest strips is one and a half to two times less than in the openwork forest strips. In favorable years, this difference in soil moisture remains throughout the growing season. The growth and development of tree species in the first half of the growing season (May-June) is carried out at the expense of moisture accumulated during snowmelt or winter rains in the lower soil layers. In the second half of the growing season, tree species receive moisture from summer precipitation that falls in late July and early August and accumulates in the upper soil layers.