Investigating Cropland's Soil Carbon Sequestration Potential to Reduce Climate Change with the Cool Farm Tool

The organic farming system significantly (P < 0.001) increased the SOC pool. The continuation of saprotrophic fungus dominance and the shift in bacterial life-history strategy from K- to R-strategy were the primary drivers of changes in the SOC pool and stability observed in soil microbial communities. By altering the dynamics of the microbial community and the agricultural system, SOC fractions were raised. Rice-vegetable pea had the highest active carbon pools (Mg ha⁻¹) in soils in 0–15 cm layers of various cropping systems (11.14), followed by soybean-buckwheat (11.00), rice-buckwheat (10.44), black gram-toria (10.16), and rice-toria (9.94). The lowest was found in rice bean-cabbage (9.16). Moreover, rice-vegetable pea had the highest carbon pool index (1.23), followed by soybean-buckwheat (1.21), rice-buckwheat (1.19), black gram-toria (1.17), and rice-toria (1.15), while rice bean cabbage (1.08) had the lowest. Lastly, rice-vegetable pea (197.29), followed by soybean-buckwheat (188.66), rice-buckwheat (181.77), black gram-toria (176.52), rice-toria (169.73), and rice bean-cabbage (140.22), had the highest carbon management index in chronological order. The rice-vegetable pea cropping system was deemed the most effective cropping system for sequestering carbon in the Sikkim Himalaya due to its higher levels of total soil organic carbon, carbon pool index, lability index, and carbon management index. Soybean-buckwheat and rice-buckwheat came in second and third place, respectively, in the carbon management index. In order to effectively plan for land resource management, the study suggested that rice-vegetable pea cropping under organic farming be promoted in the Indian Himalayan study region.