Soil microbial communities as potential regulators of N2O sources in highly acidic soils  

作　　者：Junhui Yin Huaihai Chen Pengpeng Duan Kun Zhu Naihui Li Yan Ma Yumeng Xu Jingheng Guo Rui Liu Qing Chen 

机构地区：[1]Beijing Key Laboratory of Farmyard Soil Pollution Prevention-control and Remediation,College of Resources and Environmental Sciences,China Agricultural University,Beijing 100193,China [2]State Key Laboratory of Biocontrol,School of Ecology,Sun Yat-sen University,Guangzhou 510006,China [3]Key Laboratory of Agro–Ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 410125,China [4]College of Land Science and Technology,China Agricultural University,Beijing 100193,China [5]Department of Horticulture,Northeast Agricultural University,Harbin 150030,China

出　　处：《Soil Ecology Letters》2023年第4期81-87,共7页土壤生态学快报（英文）

基　　金：support of Professor Yuzhong Li from Chinese Academy of Agricultural Sciences for the technical assistance in the isotope signature determination.This work was supported by grants from the National Natural Science Foundation of China(42007031).

摘　　要：●Soil pH was a key driver of N2O emission and sources in acidic soils.●N2O emission was significantly positively associated with the ratio of ITS to 16S.●N2O was significantly correlated with bacterial and fungal community composition.●Fungi contributed to N2O in highly acidic tea plantations and vegetable fields.Acidic soil is a main source of global nitrous oxide(N2O)emissions.However,the mechanism behind the high N2O emissions from acidic soils remains a knowledge gap.The objective of this microcosm incubation study was to pin-point the microbial mechanisms involved in N2O production processes in acidic soils.For that purpose,the isotopic signatures and microbial community structure and composition of four soil samples were examined.The results showed that highly acid soils(pH=3.51)emitted 89 times more N2O than alkaline soils(pH=7.95)under the same nitrogen(N)inputs.Fungal denitrification caused high N2O emissions in acidic soils.ITS to 16S abundance ratio was positively correlated with cumulative N2O emissions from the tested soils.The highly acid soils(pH<4.5)showed greater fungal nirK gene abundance and lower abundance of AOA-amoA,AOB-amoA,nirK,nosZ I and nosZ II genes.The unclassified Aspergillaceae fungi(63.65%)dominated the highly acidic soils and was the most strongly correlated genus with N2O emissions.These findings highlight that soil microbial community structures,denitrifying fungi in particular,shaped by low pH(pH<4.5)lead to high N2O emissions from acidic soils.

关 键 词：nitrous oxide ITS 16S ratio fungal denitrification soil pH vegetable field tea plantation 

分 类 号：S154.3[农业科学—土壤学]