The effects of different resource conservation practiceson SOC pools, soil enzymatic activities were studied under tropical lowland rice (Oryza sativa L.)- green gram (Vigna radiata) soil system in a long-term experiment,which was established in 2012. Seven RCTs i.e., conventional farmer's practice, brown manuring, green manuring, wet direct drum seeding, zero tillage, green manuring plus real time nitrogen management by customized leaf colour chart and biochar application were broadly included in the experiment.Soil organic carbon (SOC) pools were significantly higher under Green manuring treatment compared to conventional control. Soil labile carbon fractions and enzymatic activities were significantly higher under RCTs over control. Soil organic carbon was significantly higher under zero tillage as compared to other resource conservation practices as well as conventional treatments and 13% more than that of conventional control. It can be concluded from the experimental data that resource conservation practices like zero tillage could offer carbon saving by increase soil carbon stock in tropical lowland rice-green gram soil.