Effects of Elevated CO2 on Soil Organic Carbon Stabilization in a Typical Rice-wheat Rotation System
Changes in physical and chemical stabilization are considered to be important mechanisms for soil carbon cycles under elevated CO2. In this study, we evaluated the effects of elevated CO2 concentration on the soil carbon stabilization by physical and chemical methods under different N levels and with straw input cultivated in field. Results shown that soil carbon sequestrated in<53um and carbon in heavy parts treated with ZnBr (particularly at HN) was increased by elevated CO2 compared with ambient CO2, and the relationship between them was positively close. Elevated CO2 significantly decreased the loss of carbon after soil treated with HF (p<0.01), in particular at HN. There were no significant effects of elevated CO2 on carbon change after treated with Na2S2O8, but under elevated CO2 condition the carbon not removed was highest at LN. After soil was treated with H2SO4, carbon in each pool, particular in pool II, was increased at different N levels by 6.4%-25.7% and by 3.9%-24.8% under elevated CO2 and under ambient CO2 in 2004 than them in 2001, respectively, and with the increase was less under elevated CO2 than under ambient CO2 at HN. These results indicated that elevated CO2 maybe improve the increase of carbon with mineral as alkyl compounds resistant to decomposition and turnover, which were affected by nitrogen levels and debris characters such as C/N ratio.
elevated CO2 carbon stabilization mechanisms nitrogen levels
MA Hongliang ZHU Jianguo XIE Zubin GAO Ren LIU Gang ZENG Qing
Fujian Provincial Key Laboratory of Subtropical Resources and Environment,Key Laboratory of Humid Su State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy o
国际会议
2009 International Symposium on Environmental Science and Technology(2009环境科学与技术国际会议)
上海
英文
1949-1956
2009-06-02（万方平台首次上网日期，不代表论文的发表时间）