AGROCHEMICAL ASSESSMENT OF AGRICULTURAL LANDS IN THE MYKOLAIV REGION WHICH WERE FLOODED AS A RESULT OF DESTRUCTION KAKHOVKА HPP

Abstract

The impact of long-term flooding of agricultural lands due to the destruction of the Kakhovka HPP dam is highlighted. The results of experimental studies of the reaction of the soil solution, humus content, mobile compounds of phosphorus and potassium in thirteen soil samples taken on the territory of Berezneguvatе and Snigurivka territorial community of Bashtan district of Mykolaiv region are given. The condition of the soil cover of the flooded land plots was established by comparing the obtained indicators to the background values on the land plots that were not negatively affected and were characterized by the same agro-production group of soils. According to the results of studies of soil samples taken from the areas that were flooded, acidification of the soil solution compared to the background values was established in 6 areas (from 0.1 to 0.5 units of pH) and alkalinization in 6 areas (from 0.1 to 0.8 pH units). Compared with background values, the content of humus (organic matter) in 5 analyzed soil samples decreased (from 0.12 to 0.83%), in 8 it increased (from 0.1 to 1.27%) and varied from 3.4 to 6.17%. Nitrogen content by nitrification capacity in the selected samples varied from high (18.3 mg/kg of soil) to very high (1210.2 mg/kg of soil). Compared to the background value, an increase in nitrogen content from 3.4 to 1185.3 mg/kg of soil was noted at all sites. A more intense increase in nitrogen content was established in the flooded areas of the right bank compared to the flooded areas on the left bank of the Dnieper. A significant increase in the nitrogen content is caused not only by the application of highly organic silt and silt, but also by the composition of water and the duration of flooding, a moderate correlation was found between the nitrogen and humus content (r = 0.44). A significant increase (from 1.7 to 2.93 times) in the content of mobile potassium compounds in the soil was found on all surveyed land plots, their content varied from 552 to 1019 mg/kg of soil. Also, an increase in the content of mobile phosphorus compounds (from 1.1 to 3.3 times) was found in most flooded areas, and the content of mobile phosphorus compounds varied from average (19 mg/kg soil) to very high (100 mg/kg soil).