Carbon input of 4%o annually to stabilise soil carbon stock under soil–crop management in a climate change scenario

Context The sequestration of soil organic carbon (SOC) depends on the equilibrium between carbon input and output. Maintaining the proper equilibrium requires diligent management of the soil and crops that govern carbon cycling in soils. Aim This study aimed to measure the dynamics of soil organic carbon stocks to support effective soil–crop management practices, which permits a yearly 0.4% increase in soil carbon under a climate change scenario. Methods The study was conducted in the lower Indo-Gangetic Plain (IGP) of India under integrated, improved, and conventional soil–crop management practices. The SOC dynamics under a modified rice–mustard–jute cropping system were reproduced and forecasted under RCP4.5 and RCP8.5 climate change scenarios. Key results This comprehensive analysis showed that to raise organic carbon stocks by 0.4% annually, an annual carbon input of 2400 kg ha−1 would be required. The simulation indicated that SOC stocks under the integrated soil and crop combination would increase by 9.32% in the first half of the century (2050–2060), spanning the RCP4.5 and RCP8.5 scenarios. Conclusions The management strategy adopted under the integrated soil and crop system using leguminous crops as intercrops or mixed crops may be highly recommended for the jute- and rice-growing farmland to increase SOC pools in soils. Implications The results of the study can be used to guide carbon input management for SOC sequestration not only in the IGP region but also in neighbouring countries, ultimately contributing to the mitigation of climate change impacts.