以位于西南大学试验农场的紫色土长期免耕试验田为研究对象,探讨不同耕作方式-冬水田平作(DP)、水旱轮作(SH)、垄作免耕(LM)、厢作免耕(XM)和垄作翻耕(LF)对紫色水稻土总有机碳、活性有机碳及稳态碳的影响。结果表明,在0~60 cm的土壤深度内,不同耕作方式下总有机碳的平均含量为LM(22.74 g/kg)〉DP(14.57 g/kg)〉XM(13.73 g/kg)〉LF(13.10 g/kg)〉SH(11.92 g/kg);活性有机碳的平均含量为DP(3.67 g/kg)〉LF(3.49 g/kg)〉LM(3.28 g/kg)〉XM(3.17 g/kg)〉SH(2.69 g/kg);稳态碳占土壤总有机碳的百分比为LM(85%)〉SH(78%)〉XM(77%)〉LF(75%)〉DP(74%)。长期垄作免耕具有明显的碳截存效应和良好的固碳能力。
The effects of tillage system on total soil organic carbon,soil active organic carbon and soil stable organic carbon were studied in a long-term field experimental station in Chongqing,China.The content of total soil organic carbon in the 0-60 cm soil layers under different tillage systems was LM: no-till and ridge culture with rotation of rice and rape system(22.74 g/kg) DP: conventional tillage with rice only system(14.57 g/kg) XM: no-till and plain culture with rotation of rice and rape system(13.73 g/kg) LF: tillage and ridge culture with rotation of rice and rape system(13.10 g/kg) SH: conventional tillage with rotation of rice and rape system(11.92 g/kg).The order of soil active organic carbon was LM(22.74 g/kg) DP(14.57 g/kg) XM(13.73 g/kg) LF(13.10 g/kg) SH(11.92 g/kg).The proportion of soil stable organic carbon to total soil organic carbon was LM(85%) SH(78%) XM(77%) LF(75%) DP(74%).Overall,long-term LM treatment performed good effects on the soil carbon sequestration and fixation.