不同连作年限设施农用地土壤有机碳与细菌群落功能特征  

Characteristics of Soil Organic Carbon and Bacterial Communities Functional in Agricultural Lands of Facilities with Different Continuous Cropping Periods

作　　者：孔晨晨 张世文[1] 王维瑞 颜芳 宋孝心 郭丹丹 KONG Chenchen;ZHANG Shiwen;WANG Weirui;AN Fang;SONG Xiaoxin;GUO Dandan(School of Earth and Environment,Anhui University of Science and Technology,Huainan 232001,China;Beijing Cultivated Land Construction and Protection Center,Beijing 100020,China)

机构地区：[1]安徽理工大学地球与环境学院,淮南232001 [2]北京市耕地建设保护中心,北京100020

出　　处：《农业机械学报》2024年第2期326-337,共12页Transactions of the Chinese Society for Agricultural Machinery

基　　金：第三次新疆综合考查项目(2021xikk0200601);粮食作物创新团队土壤评价与质量提升岗位专家项目(BAIC02-2023);国家重点研发计划项目(2020YFC1908601)。

摘　　要：为探明不同连作年限设施农用地土壤有机碳(Soil organic carbon,SOC)与细菌群落功能变化及其动态响应关系,以北京市南郊设施农业集中地为研究区,采用时空替代法系统分析了未种植(CK)、连作年限0~5年(0~5 a)、5~10年(5~10 a)、10~20年(10~20 a)和20年以上(20 a+)SOC、细菌群落结构及其代谢功能的变化。结合冗余分析(RDA)、典型相关分析(CCA)、PICRUSt2功能预测及Mantel test探究了SOC及其活性组分与细菌优势菌群的动态响应,以及与细菌代谢功能的相互关系。结果表明:连作使研究区微生物生物量碳(Microbial biomass carbon,MBC)、易氧化有机碳(Easily oxidizes organic carbon,EOC)、SOC含量及土壤有机碳密度(Soil organic carbon density,SOCD)均随种植年限先增后减,可溶性有机碳(Dissolved organic carbon,DOC)含量在20 a+时最高,微生物熵(Q)随连作年限增加而减小。连作降低了土壤细菌的多样性,但提高了细菌种群间差异,PICRUSt2预测不同连作年限土壤细菌功能均以新陈代谢为主,5~20 a土壤细菌二级代谢功能丰度明显高于0~5 a、20 a+、CK。相对丰度前10的细菌群中Acidobacteriota与SOC及其活性组分含量均呈负相关,主导和参与SOC累积循环的关键菌群在连作20 a+后出现由富营养型菌群向寡营养和致病类菌群转变的趋势;Mantel分析显示,第3层级有53类与土壤有机碳含量呈显著相关的代谢功能(p<0.05),其中23类隶属于第1层级的新陈代谢,与EOC呈显著相关的代谢功能高达51类。本研究结果可为优化碳循环相关细菌功能群,提升小尺度设施农用地土壤碳汇功能提供参考。To investigate the changes in soil organic carbon(SOC),bacterial communities and metabolic functions,as well as the dynamic response relationships with each other in facility agricultural land with different cropping periods,organic carbon,bacterial community structure and metabolic functions in soil were systematically characterized in unplanted(CK),0 to 5 a(0~5 a),5 a to 10 a(5~10 a),10 a to 20 a(10~20 a)and more than 20 a(20 a+)of continuous cropping by using temporal-spatial substitution method in a centralized area of facility agriculture in the southern suburb of Beijing as the study area.The dynamic response of SOC and its active components to the bacterial dominant communities and their interrelationships with bacterial metabolic functions were explored with redundancy analysis(RDA),typical correlation analysis(CCA),prediction of PICRUSt2 function,and Mantel test.Based on the results,continuous cropping caused the contents of microbial biomass carbon(MBC),easily oxidizes organic carbon(EOC),SOC and soil organic carbon density(SOCD)all showed an increasing and then decreasing trend with the increase of cropping period.Dissolved organic carbon(DOC)content was the highest at 20 a+.Microbial entropy(Q)was decreased with the increase of cropping period.Continuous cropping decreased the diversity of soil bacteria and increased the differences among bacterial species.PICRUSt2 prediction showed that the functions of soil bacteria in different continuous cropping period were dominated by metabolism,and the abundance of secondary metabolism functions of bacteria was significantly higher in the soil from 5~20 a than that in the soil from 0~5 a,20 a+,and CK.Among the bacterial groups in the top 10 relative abundance,the Acidobacteriota were negatively correlated with both SOC and its active components.The key bacterial groups dominating and participating in SOC accumulation and cycling showed a shift from eutrophic to oligotrophic and pathogenic taxa after 20 a+of continuous cropping.Mantel analysis showed that a tot

关 键 词：连作年限 设施农用地 土壤有机碳 细菌群落特征 代谢功能 

分 类 号：S154.1[农业科学—土壤学]