In Russia, 8% of land is irrigated with water whose mineralization is over 1 g/1, of which 5% has a concentration of 1-2 g/1 and 3%, more than 2 g/1 [1]. The distribution of irrigated areas is irregular: 90% of the entire amount of mineralized irrigation water falls on eight regions. In Kalmykia, it accounts for 50%; in the Rostov area, 40%; and in the remaining six regions, 10-23% of the total irrigated area. Irrigation of chernozems with low-mineralization water, particularly, Cl-Na or soda-containing water, often leads to negative consequences listed below. 1. Development of secondary solonetzization and alkalinization processes whose intensity depends on pH levels and water Na~+/Ca~(2+) ratios, reclamation conditions, and soil properties. In anarable layer these processes develop during one or two years of irrigation and then extend throughout the soil profile [2-5]. 2. Deterioration of agrophysical and hydrophysical properties, degradation of soil structure, and formation of a superficial crust [6, 7]. 3. Dehumification of the top part of the soil profile caused by an increased degree of dispersion and mobility of humus resulting from the formation of exchangeable sodium, and a lower rate of supply of plant residues associated with lower crop yields [8-10]. 4. Depletion of a clay fraction in the upper soil horizons due to accelerated destruction of clay minerals and their migration [11-13]. 5. Secondary salinization occurs rarely and is conditioned largely by mineralization of irrigationwater and the amount of precipitation in periods other than the vegetation period [14-17].
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机译：在俄罗斯，有8％的土地被矿化度超过1 g / 1的水灌溉，其中5％的矿物质浓度为1-2 g / 1，而3％的矿物质浓度超过2 g / 1 [1]。灌溉区域的分布是不规则的：矿化灌溉水总量的90％分布在八个区域。在卡尔梅克（Kalmykia），占50％;在罗斯托夫地区，占40％;在其余六个地区，占灌溉总面积的10-23％。用矿物质含量低的水（特别是Cl-Na或苏打水）灌溉黑钙石，通常会导致下列不良后果。 1.二次松碱化和碱化过程的发展，其强度取决于pH值和水的Na〜+ / Ca〜（2+）比例，开垦条件和土壤性质。在可耕层中，这些过程在灌溉的一两年中发展，然后扩展到整个土壤剖面[2-5]。 2.农业物理和水物理特性的恶化，土壤结构的退化以及表皮的形成[6，7]。 3.由于交换性钠的形成导致腐殖质的分散度和迁移性增加，土壤残渣顶部的去湿作用增加，植物残渣的供给率降低，从而导致作物产量降低[8-10]。 4.由于加速了粘土矿物的破坏及其迁移[11-13]，上部土壤层中的粘土部分被耗尽。 5.次生盐渍化很少发生，主要取决于灌溉水的矿化作用和植被期以外的降水量[14-17]。
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