Abstract
The article presents the results of field studies on the effect of various doses of birch biochar on the agrophysical and agrochemical properties of degraded irrigated rice-march soil of the Akdalinsky irrigation massif of southeastern Kazakhstan. The use of biochar, depending on the application doses, increases the yield of soybeans by 0.16-1.48 t/ha or by 10-96%, rice by 0.17- 0.97 t/ha or by 6-36%, spring wheat by 0.05-1.8 t/ha or 2-65%. In general, over 3 years, the use of biochar provides 1.34-3.68 tons of additional grains of rice, wheat and soybeans in total. The introduction of biochar in doses of 15-20 t/ha for basic tillage helps to improve the bulk, increase the content of agronomically valuable and durable aggregates of the arable soil layer.