Authors:
A. S. MOTORIN,
doctor of agricultural sciences, professor, Northern Trans-Ural State Agricultural University
(7 Republic Str., 625003, Tyumen)
Abstract. The results of long-term (2009–2012) studies of water-physical properties of the moisture content of drained peat soils of the Northern Trans-Urals are presented. It is shown that the soils under drying have different water-physical properties. First of all, in the analysis it is necessary to pay attention to the value of the lowest moisture capacity (HB) of the soil. It is estab- lished that the lowest moisture capacity of medium-power peat soil in a meter layer is equal to 671.3 mm. This is 19.3 % more than for low-yielding soils and 38.9 % for peaty-gley soils. In a layer of 0.5 m, the value of HB in low- and medium-power peat soils is practically equal (303.5 and 312.8 mm). In peaty-gley soil it is less by 75.6–84.9 mm. Minimal differences in moisture content in soils are noted only for the upper peat layer 0.2 m. The advantage is medium-thick peat soil due to the low degree of peat decomposition. The optimum moisture content (0.73 HB) in the arable layer during all terms of determination and the years of research was established in medium-thick peat soil. During the years of research, the moisture content in the 0.5-me- ter layer of peaty-gley soil was in the range 0.69–0.85 HB, low power — 0.64–0.76 HB, medium power — 0.66–0.95 HB. In the layer of 0.6–1.0 m, moisture reserves remained stably high for all the years (0.89–0.92 HB). The zone of active moisture exchange of all studied drained soils is limited by the upper half-meter layer. The most significant changes in humidity occur in the plow layer. During the formation of the first mowing of perennial grasses, moisture reserves in the 0.5-meter layer were always within optimal limits (0.7–0.9 HB). With a deep bedding of groundwater (1.2–1.6 m), moisture reserves fall below the optimal level (0.47–0.71 HB). Lack of moisture causes a decrease in the yield of the second cut of perennial grasses by 46–89 % in peaty-gley soil and 25–40 % in medium-thick grass.
Keywords: peat soil, moisture, minimum water capacity, water-physical properties, groundwater.
