Influence of Climate Changes on Hydrothermal Regime of Dark Gray Podzolized Soil of Western Forest Steppe

Abstract

Thermal properties of soil are important conditions that determine the nature and intensity of soil processes, but the features of the formation of thermal and water regimes of dark gray podzolized soil of the Ukrainian Forest Steppe are insufficiently studied. The purpose of the presented materials is to highlight the dynamics of the annual course of temperature and humidity of the air and dark gray podzolized soil to determine the peculiarities of the formation of its hydrothermal regime in modern agro-climatic conditions of the Forest Steppe zone. The study of soil temperature was carried out during 2008-2019 in the Rivne region using generally accepted standards and methods (DSTU ISO 11464-2007, DSTU ISO 11465-2001, DSTU B B.2.1-17:2009, DSTU B B.2.1-25:2009). Surface air temperature observations throughout the study period indicate an increase in average annual temperature, and five-year averages of the sum of effective air temperatures above 10°C show tends to increase. The study of the relationship between the temperature of the surface air layer and dark gray soil in the Rivne region confirmed that the correlation of these indicators is linear. Analyzing the dynamics of temperature indicators, it should be noted a significant increase in maximum soil temperatures, due to which there is an increase in average annual temperatures. Detailing of soil warming indicators according to the data of ten years showed that during 2008-2017 the soils warmed up much more than in the average during the whole period of meteorological observations. According to the accepted classification, the studied soils belong to the seasonally freezing type, moderately warm subtype and genus with medium heat supply. The results obtained during the study allow to justify changes in the hydrothermal conditions of dark gray podzolized soil and determine the needs for corrective measures in crop production to maintain sustainable yields and ensure enhanced fertility reproduction