辽宁省农田土壤有机碳含量特征与影响因素  

Variation of soil organic carbon and the influencing factors in croplands of Liaoning Province,China

作　　者：陈思宇 律泽[1] 张仰 王健[2] 李国琛[2] 王超[2,3] CHEN Siyu;LV Ze;ZHANG Yang;WANG Jian;LI Guochen;WANG Chao(School of Municipal and Environmental Engineering,Shenyang Jianzhu University,Shenyang 110168,China;Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China;Key Laboratory of Terrestrial Ecosystem Carbon Neutrality,Liaoning Province,Shenyang 110016,China)

机构地区：[1]沈阳建筑大学市政与环境工程学院,沈阳110168 [2]中国科学院沈阳应用生态研究所,沈阳110016 [3]辽宁省陆地生态系统碳中和重点实验室,沈阳110016

出　　处：《生态学杂志》2024年第9期2769-2776,共8页Chinese Journal of Ecology

基　　金：中国科学院战略性先导科技专项(XDA28020301);中国科学院沈阳应用生态研究所自主部署重大项目(IAEMP202201);中国科学院青年创新促进会会员(Y2022064)资助。

摘　　要：作为中国重要粮食生产基地的东北农田,由于不合理利用,土壤有机碳含量出现逐年下降的趋势。本研究以辽宁省典型作物玉米和水稻土壤为对象,共采集444份土壤样品,分析土壤有机碳及其组分(微生物生物量碳、死亡残体碳和可溶性有机碳)的含量,并解析影响有机碳的关键因素。结果表明:水稻田土壤有机碳(SOC)、微生物生物量碳(MBC)含量和MBC/SOC值均高于玉米田土壤,而水稻田土壤可溶性有机碳含量、细菌残体碳、真菌残体碳和土壤残体碳总量低于玉米田土壤;相关分析显示,玉米田和水稻田的SOC与MBC和微生物残体碳具有显著正相关性;回归分析显示,水稻田SOC与MBC和微生物残体碳的斜率较低;随机森林模型分析显示,土壤C/N和真菌残体碳是玉米田和水稻田土壤SOC的关键影响因素,但两者对玉米田土壤SOC的解释度更高;玉米田和水稻田SOC组分及关键影响因素存在显著差异,微生物周转过程对玉米田SOC影响更大,土壤性质对水稻田SOC含量起到主要影响。本研究为科学调控东北农田土壤有机碳提供基础数据和理论基础。Northeast China is an important grain production base at the national level.The content of soil organic carbon in this area has been decreasing year by year due to the irrational use.In this study,a total of 444 soil sam⁃ples were collected from maize and rice fields(two typical croplands)in Liaoning Province.The contents of soil organic carbon and its components(microbial biomass carbon,necromass carbon,and dissolved organic carbon)as well as their influencing factors were analyzed.The results showed that the contents of soil organic carbon(SOC),microbial biomass carbon(MBC)and MBC/SOC in rice field were higher than those in maize field,while the contents of dissolved organic carbon,bacterial necromass carbon,fungal necromass carbon,and total necromass car⁃bon in rice field were lower than those in maize field.SOC in maize and rice fields had a significant positive correlation with MBC and microbial necromass carbon,while SOC in rice field had a lower slope with MBC and microbial necromass carbon.Results of random forest model analysis showed that soil C/N ratio and fungal necromass carbon were the key factors influencing SOC in maize and rice fields,with higher interpretation for SOC in maize field.There were significant differences in SOC components and key influencing factors between maize and rice fields.Microbial turnover process had stronger influence on SOC in maize field,while soil properties had a dominant influence on SOC content in rice field.This study provides basic data and a theoretical foundation for the scientific regu⁃lation of soil organic carbon in the croplands of Northeast China.

关 键 词：土壤有机碳 微生物生物量碳 微生物残体碳 

分 类 号：S153.6[农业科学—土壤学]