REVISION OF THE CLASSIFICATION OF SALINE SOILS OF RUSSIA

Based on combined study of the composition of soil solutions and water extracts in Chestnut and Solonetz soils of Russia, the diagnostic fac tors of the chemistry of salinization are revised-(> 1.0 for chloride, 0.6-1.0 for sulfate-chloride, and 0.3-0.6 for chloride-sulfate), as w ell as the optimal (1.0-2.5 g/l) and critical (2.5-3.5 g/l) concentrat ions of soil solutions for weakly and moderately salt-resistant crops. Identification of a ''very weak extent of soil salinization,'' which corresponds to 0.06-0.10 percent of the total of toxic salts in chlori de-sulfate salinization, is proposed.