Physical properties of soils and the simulation of the hydrothermal regime for the complex soil cover of the Vladimir Opol’e region

Abstract

A methodological approach to the physically sound mathematical simulation of the hydrothermal regime for a complex soil cover on an agricultural field scale was proposed. To realize the approach, it is necessary (1) to restore the hydrothermal regime of two contrasting soils using a physically sound mathematical model on the basis of the experimental thermophysical and hydrophysical characteristics, (2) to adapt and optimize the model using the available experimental regime data, (3) to determine the hydrophysical and thermophysical properties for the entire plot under study using pedotransfer functions, and (4) to restore the hydrothermal regime of the entire soil plot using a mathematical model and the meteorological data for a specific time period. The proposed procedure allows simulating the hydrothermal regime of an agrogray soil complex in the Vladimir Opol’e region with a normalized standard error of about 8%. The analysis of the hydrothermal regime for the soil cover of the studied plot calculated from the meteorological data for the period from May to August of 2009 showed that the lower temperature values were confined to the areas of the agrogray soils with the second humus horizon: their average temperature was lower than the temperature of the agrogray soils by 0.44, 0.93, and 1.32°C at depths of 20, 40, and 70 cm, respectively, and the differences between their sums of the active temperatures for the considered period of 2009 reached 89 and 74°C at depths of 20 and 40 cm, respectively.