黄土高原碳汇系统研究展望

Key Issues of Earth System Science in the Study of Carbon Sinks in the Loess Plateau

全球温度升高1.2℃,应对气候变化已经到了刻不容缓的地步。2019年9月,中国政府承诺中国在2030年碳达峰,在2060年碳中和,这是一份巨大担当,也是一个巨大的挑战。碳中和的达成需要节能减排,还需要负排放技术和增加生态、地质碳汇。能源结构的调整和CCUS等负排放技术的发展需要几十年的时间,亟需要调查和研究生态和地质碳汇的现状并且增加碳汇潜力。全球范围的碳汇清查主要依靠“自上而下”和“自下而上”的估算方法,而国家级别的区域碳汇清查目前还是一个难点。黄土高原是最早起步进行退耕还林还草生态工程的地区,也是生态脆弱区。目前,黄土高原区域的碳汇调查和研究尚属于起步阶段。基于国家“双碳”战略需要和黄土高原生态文明建设,笔者从地球系统科学角度,回溯黄土高原的碳汇调查研究成果,总结黄土高原区域碳汇评估的方法体系,包含有机碳汇系统和无机碳汇系统。其中,有机碳汇系统包含有机质碳储量子系统和生态碳汇子系统的研究;无机碳汇系统主要包含碳酸盐碳汇系统和硅酸盐碳汇系统。在此基础上,从地球系统科学角度提出黄土高原碳汇调查研究建议。

With the global temperature rising by 1.2℃,it is urgent to deal with climate change.In September 2019,the Chinese government promised that China will reach its carbon peak in 2030 and become carbon neutral in 2060,which is a huge responsibility and a huge challenge.The achievement of carbon neutrality requires energy conservation and emission reduction,as well as negative emission technologies and an increase in ecological and geological carbon sinks.The adjustment of the energy structure and the development of negative emission technologies such as CCUS will take decades.There is an urgent need to investigate and study the current status of ecological and geological carbon sinks and increase the potential of carbon sinks.The global carbon sink inventory mainly relies on the"top-down"and"bottom-up"estimation methods,while the national-level regional carbon sink inventory is still a difficult problem.The Loess Plateau is the first area where the ecological project of returning farmland to forests and grasslands started,and it is also an ecologically fragile area.The current investigation and research on carbon sinks in the Loess Plateau is still in its infancy.Based on the needs of the national carbon neutral strategy and the construction of ecological civilization on the Loess Plateau,this paper begins to review the research results of carbon sinks on the Loess Plateau from the perspective of earth system science.Firstly,the method system of carbon sink assessment in the Loess Plateau is summarized,and then it is further summarized that the carbon sink system of the Loess Plateau mainly includes organic carbon sink system and inorganic carbon sink system.Among them,the organic carbon sink system includes the research on the organic carbon storage sub-system and the ecological carbon sink system.The inorganic carbon sink system mainly includes carbonate carbon sink system and silicate carbon sink system.Finally,from the perspective of earth system science,the suggestions are given for the investigation and research of carbon sinks in the Loess Plateau.