长白山阔叶红松林土壤真菌和细菌N_(2)O排放对施氮和降水变化的响应  

Responses of soil fungal and bacterial N_(2)O emissions to nitrogen fertilization and precipitation changes in a broad⁃leaved Korean pine forest in Changbai Mountains,China

作　　者：张蕾 雷馥歌 宿振浩 杨佳诺 张悦[2,3] 郭忠玲 韩旭[1] ZHANG Lei;LEI Fuge;SU Zhenhao;YANG Jianuo;ZHANG Yue;GUO Zhongling;HAN Xu(Forestry College of Beihua University,Jilin 132013,Jilin,China;Key Laboratory of Forest Ecology and Silviculture,Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110016,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]北华大学林学院,吉林吉林132013 [2]中国科学院沈阳应用生态研究所森林生态与保育重点实验室,沈阳110016 [3]中国科学院大学,北京100049

出　　处：《生态学杂志》2025年第2期417-424,共8页Chinese Journal of Ecology

基　　金：国家重点研发计划项目(2022YFF1300500);全国大学生创新创业项目(120722145)资助。

摘　　要：以长白山阔叶红松林长期(8年)施氮和减少降水固定样地土壤为对象,通过室内培养试验,结合抗生素抑制技术,分析真菌和细菌两类土壤微生物N_(2)O排放对施氮和减水的响应。结果表明:对照处理中,土壤N_(2)O排放为0.79 nmol·g^(-1)·h^(-1),单独减水、施氮处理和同时减水施氮处理均显著促进了土壤N_(2)O的排放,分别为3.55、1.84和1.84 nmol·g^(-1)·h^(-1),且减水和施氮处理之间存在显著交互作用。其中细菌N_(2)O排放受施氮和减水处理的影响,施氮处理促进细菌N_(2)O排放进而提高土壤总N_(2)O排放量。真菌N_(2)O排放主要受减水处理影响,减水施氮处理促进真菌N_(2)O排放进而提高土壤总N_(2)O排放量。而减水处理所造成的N_(2)O排放增加归因于细菌和真菌的共同作用。在对照、减水和施氮处理中,N_(2)O排放以细菌为主,相对贡献率为90.3%、68.2%和91.1%;而在减水施氮处理中,N_(2)O排放以真菌为主,相对贡献率为68.5%。由此可见,干旱情景下,长期施氮会改变土壤N_(2)O排放的主要微生物种类,直接影响土壤真菌和细菌N_(2)O排放量,进而影响土壤N_(2)O的排放总量,对森林生态系统氮循环过程造成影响。Combined with the antibiotic inhibition technique,we examined the responses of soil fungal and bacteri⁃al N_(2)O emissions in a laboratory culture experiment.Soil samples were collected from fixed plots with long⁃term(eight years)nitrogen application and precipitation reduction in a broad⁃leaved Korean pine forest in Changbai Mountains.Results showed that soil N_(2)O emissions were 0.79 nmol·g^(-1)·h^(-1)in the control.Nitrogen application,precipitation reduction,and simultaneous precipitation reduction and nitrogen application significantly enhanced soil N_(2)O emissions,which were 3.55,1.84 and 1.84 nmol·g^(-1)·h^(-1),respectively.There was a significant interaction between precipitation reduction and nitrogen application.Bacterial N_(2)O emissions were affected by nitrogen applica⁃tion and precipitation reduction.Nitrogen application promoted bacterial N_(2)O emissions,thereby promoting total soil N_(2)O emissions.Fungal N_(2)O emissions were mainly affected by precipitation reduction.Simultaneous precipitation reduction and nitrogen application promoted fungal N_(2)O emissions,thereby promoting total soil N_(2)O emissions.The increase in N_(2)O emissions caused by precipitation reduction treatment was attributed to the interaction of bacteria and fungi.In the control,precipitation reduction,and nitrogen application treatments,N_(2)O emissions were mainly contributed by bacteria,with relative contribution rates of 90.3%,68.2%and 91.1%,respectively.In the nitrogen application and precipitation reduction treatment,N_(2)O emissions were mainly contributed by fungi,with a contribution rate of 68.5%.Therefore,long⁃term nitrogen application under drought scenario would alter the main microbial species involved in soil N_(2)O emission,directly affect the amount of N_(2)O emissions from soil fungi and bacteria,thereby affecting total soil N_(2)O emissions,which influence nitrogen cycling in forest ecosystems.

关 键 词：土壤N_(2)O排放 真菌 细菌 氮沉降 减水 

分 类 号：S791.247[农业科学—林木遗传育种]