Use of vermicompost for recovery of soil fertility and increase of field crop capacity under conditions of the dry-steppe zone

This paper describes the results of applying vermicompost in various doses to soil, and its effect on the soil density as well as on the capacity of crops achieved in the Pavlodar region, the Republic of Kazakhstan. The experiment consisted of 7 objects: control, N40P20; vermicompost 1.5 t ha(-1), vermicompost 3 t ha(-1), vermicompost 5 t ha(-1), vermicompost 7 t ha(-1), vermicompost 9 t h(-1). The research has shown that vermicompost use contributes to the efficient use of moisture by creating an optimal composition of the arable soil layer. On average, the application of vermicompost to soil improves the density of the arable layer, bringing its parameters closer to the established optimal values for wheat (1.26-1.30 g cm(-3)), peas (1.23-1.29 g cm(-3)) and buckwheat (1.23-1.26 g cm(-3)). Productive moisture deposits in the arable layer of soil with vermicompost under wheat were from 4.6 to 7.1 mm, under pea - from 3 to 10.4 mm and under buckwheat - from 3.9 to 4.7 mm. The vermicompost use in the amount of 1.5-9 t ha(-1) contributes to an increase in the humus content in the arable layer of soil. That is, each ton of vermicompost used increases the humus content in the soil by an average of 0.07%. On average, the application of 1 t ha(-1) of vermicompost provided an increase in the content of labile phosphorus by 4.7 mg kg(-1) of soil. The studied crops produced relatively high yields, namely wheat after the application of 5 and 9 t ha(-1) of vermicompost, and of pea and buckwheat owing to 7 and 9 t ha(-1) of vermicompost added to soil. At the same time, wheat achieved a yield increase of 2.7-2.9 t ha(-1), peas - of 4.0 and 4.2, and buckwheat - of 2.6-2.7 t ha(-1).