中文摘要：

农田碳汇管理措施的增汇效应是全球变化研究内容的重要命题之一。本文基于土地动态模拟系统（DLS）模拟了2012与2020年全国栅格尺度的农田分布,同时利用基于遥感反演的1988、2000年农田分布数据,应用CENTURY模型模拟了实施免耕、秸秆还田措施下中国1988～2020年农田土壤有机碳贮量的时空变化特征,分析了1988～2000年、2000～2012年与2012～2020年3个时段中国农田土壤有机碳贮量变化情况,揭示了九大农业生态区农田土壤有机碳贮量变化的时空分异特征。在不实施农田碳汇管理措施的情况下,1988～2000年全国大部分地区的农田土壤有机碳呈增长态势;而2000～2012年的全国农田土壤有机碳贮量出现一定幅度的下降。2012～2020年间,虽然全国范围内的土壤有机碳贮量表现为下降趋势,但下降幅度较2000～2012年间显著减少。研究结果表明,实施秸秆还田与免耕措施能够有效促进农田土壤有机碳贮量的增加,同时这两种管理措施的增汇效应具有显著的空间分异特征,黄淮海区、长江中下游区、华南区和西南区的增汇效果相对明显。上述研究结论为制订和实施农田增汇措施、减缓气候变化影响并保障农业发展的相关政策提供决策参考信息。

英文摘要：

On the basis of the previous relevant research,this paper simulates changes of spatial pattern of cropland during 2000～2012 and 2012～2020 by using DLS.After exploring the dynamics of soil organic carbon stocks of cropland in China cropland from 1988 to 2000 through the CENTURY model on the basis of remotely sensed cropland patterns in gird pixel level,this paper simulates the dynamics of soil organic carbon stocks for the two periods during 2000～2012 and 2012～2020,respectively,using the simulated dynamics of cropland patterns and by setting and running the CENTURY model at the grid pixel level and the aggregated nine agri-ecological zones.Simulation results indicated that the dynamics of soil organic carbon stocks experiencing an increasing trend from 1988 to 2000 in most areas of China under the conditions that there are no carbon sequestration measures implemented;While in the period between 2000 and 2012,the soil organic carbon stocks decreased to some extent for the entire nation.During 2012～2020,although the soil organic stocks of cropland is still showing a decreasing trend,the decline level is apparently less than that occurred in the period between 2000 and 2012.The simulation results under the condition of implementing the soil carbon sequestration measures indicated that the soil carbon sequestration endeavors including implementing non-tillage and crop residual return practices have positive effect on the increase of soil carbon stocks although there are identified evidential regional differences for this effect.Estimate results can supply us with valuable information,which can be used to guide the implementation of carbon sequestration management of cropland.In addition,the research results can also be used for decision-making for mitigating for the impacts from climate changes and advancing the agricultural production.