Effect of integrated nutrients management on soil organic carbon pool in Vertisols of Malwa region, Madhya Pradesh, India

Integrated nutrient management gained importance not only in increase yield of crops but also in maintain the soil health and fertility. The present study was conducted during Kharif season of 2022-23 at the research farm of AICRP for Dryland Agriculture, College of Agriculture, Indore, India. Soybean was grown in a randomized block design with nine treatments and three replications. The treatments were control (T1); N20P13 (T2); N30P20 (T3); N40P26 (T4); N60P35 (T5); N20P13 + FYM @ 6 t ha-1 (T6); N20P13 + Crop Residues @ 5 t ha-1 (T7); FYM @ 6 t ha-1 (T8) and Crop Residues @ 5 t ha-1(T9). The results of the study showed that the application of N20 and P13 with organic manure FYM @ 6 t ha-1 (T6) improved the status of available nutrients and soil organic carbon. Total organic carbon recorded was highest in N20 P13 + FYM @ 6 t ha-1 (T6) than other treatments. Very labile carbon pools value varied from 3.04 to 1.68 g kg-1from 0-10 to 30-45 cm depth of the soil. The value of labile carbon was varied from 2.02 to 0.88 g kg-1 from 0-10 to 30-45 cm depth. Less labile carbon value was higher under control and the lowest was found in treatment FYM @ 6 t ha-1 + N20 P13 (T6). Significantly higher content of non-labile soil organic carbon was found under application of FYM @ 6 t ha-1 + N20 P13. Integrated nutrient management practices are well suited for augmenting the soil organic carbon pool in soils.