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Purpose: to study the effect of different levels of moisture on chernozems properties and the crop yield. Materials and methods. Research objects are ordinary chernozem irrigated with fresh water; ordinary chernozem, irrigated with low-mineralized water; southern chernozem irrigated with fresh water (Rostov region). Analysis and evaluation of these soil samples were carried out according to generally accepted methods. Mathematical processing of the data was carried out according to B. A. Dospekhov. Results. It was found that the average yield of agricultural crops in the 0.8 m variant compared to 1 t decreased by 2–3 % (within the limits of reliability of the experiment), and the water saving was 13–18 %. An increase in the water load (1.3 m) during 4-year irrigation with low-mineralized water of sulphate-sodium composition increased the amount of sodium to 9 % of the total soil absorbing complex (AUC) with a simultaneous decrease in the calcium proportion to 69 % of the total AUC and the transformation of soils from weakly to medium alkaline (1.15 mmol/100 g). It was revealed that for 4 years of research, when irrigating chernozems with fresh water in options 1 m and 0.8 m, a positive humus balance is observed, and on ordinary chernozems irrigated with low-mineralized water, and southern chernozems with natural solonetzicity, a negative humus balance is traced in all variants. Conclusions. Comparing the results on soil properties, the yield of cultivated crops and the efficiency of the use of irrigation water at various levels of moisture, one should give preference to soil moisture at a rate calculated for the biological need of plants. It is allowed to reduce the irrigation rate from the calculated one by 20 %, since at this level the chernozem fertility is preserved, the irrigation water consumption is reduced with a slight shortage of cultivated crops yield. |
