ВЛИЯНИЕ ЗАЛЕЖЕЙ НА ВОДНО-ФИЗИЧЕСКИЕ СВОЙСТВА КАШТАНОВЫХ ПОЧВ

Abstract

Modern arable land in the Republic of Tyva is located on chestnut soils (69%) and chernozems (25%), but the former are characterized by low fertility. Soil fertility depends on the particle size distribution, structure, water-air regime, etc. Durind agricultural use of soils, the disturbance of the structure, especially of light particle size distribution, as well as depletion of humus and nutrient reserves can occur in them. Therefore, the aim of our work was to identify the influence of fallows on the change in the waterphysical properties of chestnut soils of the BarunKhemchiksky district of the Republic of Tyva. The chestnut soils of fallow and arable lands of the Barun-Khemchiksky district of the Republic of Tyva with the laying of two soil sections in arable and fallow fields were chosen as the object of the study. Soil samples from two horizons (arable and subsurface) were selected by the five-spot method. The water properties of these soils were subjected to the following analyzes: determining the water permeability of the soil according to the method of N. A. Kachinsky, determining the speed and height of rising water, determining the total capillary moisture capacity. As a result, it was found that the soil cover of the studied territories is represented by light loamy chestnut soils. Samples of fallow soil showed good water permeability with the amount of incoming water 80–100 mm per 1 hour. The water-lifting rate of soil arable land samples is slightly greater than the soil samples of the fallow: the soil sample of the arable layer of the arable land was completely moistened after 20 minutes, and the soil sample of the arable horizon of the fallow – only after 40 minutes. The moisture capacity of the fallow soil samples turned to be slightly higher than the arable land. An analysis of the studied samples indicates the improvement in the water-physical properties of the chestnut soils of the fallow compared with the arable field. Relatively low moisture capacity and accelerated water capacity indicate a destroyed and dispersed structure of arable land.