Physical-chemical and water-physical properties of agricultural soils on inter-mountain hollows of Mountain Altai

The purpose of the research is the study the basic physical,chemical and water-physical properties of soils of high and medium mountain basins of the Altai mountains under different types of agricultural use (arable land, hayfields, pasture). The main features of chestnut and light chestnut soils of high-mountain basins, dark chestnut soils and common chernozem of mid-mountain basins are established. These are a light granulometric composition with a high content of coarse soil, a sharp decrease of humus content and cation exchange capacity down the profile, slightly alkaline reaction of medium, and perfect structural state, except for the lower horizons of light chestnut soil. By density of the humus horizon, the soils of hayland and pasture belong to the soils rich in organic matter. Considerable density is noted also in the chernozem ordinary under an arable land where for many decades usual dump plowing is applied, minimum - in the dark-chestnut soil under an arable land where in recent years processing is carried out by a diskator which basic purpose - preparation of the soil for crops without preliminary plowing. The density of arable horizon on arable land correspond to typical values for a cultivated or a new-ploughed arable land. With the depth of the soil profile, this ratio increases, but it is lower than typical values for the subsurface horizons. The density of the solid phase varies slightly. In the upper organogenic horizons of the hayland and pasture, it is low due to the occurrence of organic matter. In the lower horizons, it is slightly higher and corresponds to the density of the solid phase for mineral soils. The porosity of the studied soils is in inverse proportion to density. The porosity of the upper horizons is perfect, and the horizons correspond to the cultural-arable layer. The porosity of the lower horizons is satisfactory. The hygroscopic moisture content of the soils under study varies in the wide range (0,7-9,9%). The maximum hygroscopicity in the sandy loam horizons is low (2-4%) and it is higher in loamy horizons (4-7%). The permanent wilting point ranges from 2,7 to 11,7%, and total water capacity - from 25,9 to 50,4%. Comparison of physical-chemical and water-physical properties of the studied soils of intermountain basins of the Altai Mountains with those of the same type of soils of the Altai territory and adjacent regions of Western Siberia indicates their proximity and even some advantage.

mountain and mid-mountain hollows, soils, humus, carbonates, silt, medium reaction, structural and aggregate state, density, porosity, full field moisture capacity, lowest field moisture capacity