Hydrus’s-1D capability for assessment of soils water regime

Abstract

Many areas of the world already have water shortages, and climate change could make this problem worse. Water regime is one of the components of soil system and it is very important for agriculture during nowadays climate change. Due to soil moisture nutrients become available for plants, chemical elements can migrate as radial, as lateral directions. Different soils have immanent features in the movement of water, so and movement of all dissolved in water elements. The aim of this research is comparative assessment of water dynamic between different two soils types located in similar climate conditions. These soils are characterized own texture because of features their genesis, first parent materials. For the simulation of water regime, we used well-known program Hydrus-1D. For it, we were compared next parameters: pressure head, water content, hydraulic conductivity and hydraulic capacity between Haplic Luvisol and Luvic Chernozem. On base of soil texture, we calculated some parameters becoming from modelling. These soil parameters assessed in fifth times: 0th, 15th, 30th, 45th, and 60th days. Thus, during of observation time these parameters were showing significant differences between Haplic Luvisol and Luvic Chernozem, despite the similar soil forming factors. The main difference is, first, their profile distribution, and then their quantitative values of parameters. Considering the location of the studied soils on Agroecosystems, the obtained data are important for the practical use of agro-technologies. Using of Hydrus-1D, we can also predict the soils contamination. Soil leaching processes is significantly relationship with vertical transport of water. This poses a risk both the loss of the nutrients from the soil and the contamination of the groundwater [1]. Therefore, the quality of the last is closely linked to the ability of soils to infiltrate water. Significant results of our researching indicate achieved in the simulation during the first 30 days. Therefore, for modelling it is advisable to choose periods of control over parameters of the Water regime in 5-10-20-30 days. Compared to Haplic Luvisol Luvic Chernozem have optimal indices of its texture, that provide better parameters of water regime, which is due to the higher content of fine particles. Illuvial clay of Haplic Luvisol, because of elluvial-illuvial processes, has an indicated effect on the vertical distribution such a parameter of the water regime as water content and less influence on the hydraulic capacity. When included in the simulation the real amount of precipitation during the observation, data on the corresponding changes for hydraulic conductivity and less for water pressure were obtained. It is likely that the more displayed effect of rain on day 45th than in other periods maybe explained by the nature of the precipitation (downpour rather than prolonged rain).