Assessment of effect and feasibility of Sphagnum planting on soil carbon sink in paddy field

Abstract Aims Slowing or reducing the increase of carbon dioxide in the atmosphere has become an international focus. Agricultural emissions, one of the most important sources of atmospheric carbon, are also a concern. How to increase agricultural carbon capture without hindering the development of agriculture has become an urgent matter. Methods This study was carried out in a mountainous area of southwest China. The carbon sinks of paddy fields were calculated by the sample plot inventory method, and the feasibility of replanting paddy fields in the study area and similar areas with Sphagnum was discussed from various aspects based on the actual local conditions. Results The results showed that the total soil organic carbon of 0-10cm in this study area was 15739.58t, about 35.18t/hm2. The soil organic carbon of 0-10cm in paddy field was about 12.34 t/hm2, and the carbon content of peat was more than three times that of paddy soil. Without the planting cost, the output value of Sphagnum planting in the study area can reach 9–10 times of that of rice. Moreover, Sphagnum planting in the study area had low requirements on soil nutrients and requires almost no manual management, the planting cost was much lower than that of rice planting. Conclusion In this study area, Sphagnum cultivation can take into account both economic and ecological benefits, which is an ideal agricultural model at present. However, due to its great environmental limitations, further research is needed to promote it.