河北坝上高原小滦河流域古土壤碳库地质成因和稳定性评价  

Geological origin and stability of paleosol carbon pool in the Xiaoluanhewatershed,Bashang plateau,Hebei Province

作　　者：卫晓锋 王京彬[2] 孙紫坚[3] 魏浩 李霞 陈自然[2] 孙厚云 WEI Xiaofeng;WANG Jingbin;SUN Zijian;WEI Hao;LI Xia;CHEN Ziran;SUN Houyun(Sino-Zijin Resources Ltd.,Beijing 100012,China;Beijing Institute of Geology for Mineral Resources,Beijing 100012,China;China University of Geosciences(Beijing),Beijing 100083,China;Hebei Province Collaboralive Innovation Center for Sustainable Utilization of Water Resources and Optimization of Industrial Sructure,Hebei GEO University,Shijiazhuang,Hebei 050031,China;China Institute of Geo Environment Monitoring,Beijing 100083,China)

机构地区：[1]中色紫金地质勘查(北京)有限责任公司,北京100012 [2]北京矿产地质研究院有限责任公司,北京100012 [3]中国地质大学(北京),北京100083 [4]河北地质大学河北省水资源可持续利用与产业结构化协同创新中心,河北石家庄050031 [5]中国地质环境监测院,北京100083

出　　处：《地质学报》2022年第6期2173-2183,共11页Acta Geologica Sinica

基　　金：河北省重点研发计划项目(编号19224205D);中国地质调查局项目(编号DD20160229-01,DD20190822)联合资助的成果。

摘　　要：土壤碳库是陆地生态系统中最大的碳库,以往研究主要针对现代土壤碳库,而古土壤的碳库特征研究相对薄弱。本文以河北坝上高原小滦河流域古土壤为研究对象,通过光释光(OSL)年代学、元素地球化学、团聚体分析方法,研究了风成沙地稀疏草地单元和河湖残积灌草混合单元内古土壤碳库特征。结果表明:古土壤形成时代为5.7~3.3 ka的全新世温暖期,气候温暖湿润,雨水充足,发育以松和蒿属为主要建群种的针叶林-草原植被。碳库以有机碳(SOC)为主,平均有机碳密度为3.85 kg/m^(2),有机碳库储量为153.1×10^(7)kg。河湖相沉积物微团聚体的含量较高,对古土壤层碳库的物理保护作用较强,碳库稳定性较高;风积相沉积物微团聚体含量相对较低,加速有机碳的分解,碳库稳定性较差。提出不同沉积单元的土地利用保护方式,减少土壤有机碳的分解流失,支撑当地碳达峰、碳中和工作推进。Soil carbon pool is the largest carbon pool in the terrestrial ecosystem.Previous studies mainly focused on the modern surface soil carbon pool,while research on the characteristics of ancient soil carbon pool is relatively limited.In this paper,taking the paleosol as the research object in the Xiaoluanhe watershed on Bashang plateau,Hebei Province,the characteristics of paleosol carbon pool of sparse grassland unit in an aeolian sandy layer and grass mixed ground unit in residual accumulation of rivers and lakes were analyzed by means of Optically Stimulated Luminescence(OSL)chronology,elemental geochemistry and aggregation classification method.The results show that the ages of paleosol in the study area were 5.7~3.3 ka in the Holocene geological period with warm and humid climate and adequate rainfall.The main species of coniferous forest-steppe vegetation were Pinus and Artemisia.The carbon pool was formed mainly by organic carbon(SOC),with an average SOC density of 3.85 kg/m^(2),and the SOC storage of 153.1×10^(7)kg.The micro-aggregate content of river and lake sediments is higher,and provides strong physical protection to the carbon pool of paleosol layer,leading to higher stability of the carbon pool.However,the micro-aggregate content of aeolian sand layer sediment is relatively lower,and the physical protection provided to the carbon pool is weaker,which will accelerate the decomposition of organic carbon to a certain extent and decrease the stability of carbon pool.Different ways of protection and utilization should be adopted based on different origins in the Quaternary coverage areas,which will reduce the decomposition and loss of soil organic carbon.It is of great significance to promote local carbon storage and carbon neutralization work.

关 键 词：古土壤 光释光(OSL)年代学 有机碳 稳定性 坝上高原 河北 

分 类 号：S153[农业科学—土壤学]