中国保护性耕作净碳汇的时空格局

研究中国保护性耕作净碳汇的时空格局对其推广政策的合理制定具有重要意义。在分析保护性耕作固碳排碳机理和构建其测度方法的基础上,以中国各省（市、自治区）为单元,对2000—2019年中国保护性耕作净碳汇的时空格局进行分析,并对其潜力进行预测。结果表明：（1）每年保护性耕作的碳汇基本都是碳排的2倍,土壤固碳占保护性耕作碳汇的2/3以上,生物固碳占比小于1/3。（2）中国保护性耕作净碳汇在时间上呈现逐年递增趋势,其中,华北、西北和东南地区增幅较大;在空间上表现为扩张—集聚—扩张态势,其重心由北向南移动。（3）中国保护性耕作净碳汇具有明显的空间非均衡性特征,2019年呈现华北、西北和东南地区“三足鼎立”之格局,河南、山东、内蒙古、新疆、安徽、湖北和江西7省区属于高碳汇区,河北、吉林、陕西和山西属于低碳汇区,其他省份属于碳中和区。（4）2020—2030年中国保护性耕作的净碳汇潜力继续保持增长态势,2030年的峰值将处于5794.38万~7962.93万t C之间。

Study on spatio-temporal pattern of conservation tillage on net carbon sink in China

Studying the spatio-temporal patterns of net carbon sinks under conservation tillage is of great significance to the formulation of policies. Based on the analysis of the mechanism of carbon sink and emissions and the construction of its measurement method under conservation tillage, this paper analyzed the spatio-temporal pattern of net carbon sink and predicted its potential under conservation tillage from 2000 to 2019 in the provinces (autonomous regions and municipalities, hereafter provinces) of China. The results showed that: first, the carbon sink under conservation tillage is about twice the carbon emissions, soil carbon sequestration accounts for more than 2/3 of carbon sink, and biological carbon sink accounts for less than 1/3. Second, from 2000 to 2019, the net carbon sink under conservation tillage in China showed an increasing trend year by year, and the net carbon sink in North, Northwest and Southeast China increased significantly. The net carbon sink showed a trend of expansion-agglomeration-expansion in space, with the center of gravity shifting from north to south. Third, the net carbon sink under conservation tillage in the whole country had the characteristics of obvious spatial imbalance. In 2019, there was a "three-legged" pattern in North, Northwest and Southeast China. The seven provinces of Henan, Shandong, Inner Mongolia, Xinjiang, Anhui, Hubei and Jiangxi belong to high-carbon sink areas, Hebei, Jilin, Shaanxi, and Shanxi belong to low-carbon sink areas, and other provinces belong to carbon-neutrality areas. Fourth, the net carbon sink potential under conservation tillage from 2020 to 2030 will continue to increase, and the peak value will be between 57943800 t C and 79629300 t C in 2030.