The effect of soil moisture on the response by fungi and bacteria to nitrogen additions for N_(2)O production  

作　　者：Lei Zhang Junqiang Zheng Xu Han Junhui Zhang Chengxu Li Shicong Geng Shijie Han 

机构地区：[1]Department of Boundary Layer Ecology,Key Laboratory of Forest Ecology and Management of Chinese Academy of Science,Institute of Applied Ecology,Shenyang 110000,People’s Republic of China [2]Department of Resource and Environmental Science,University of Chinese Academy of Sciences,Beijing 100039,People’s Republic of China [3]Yellow River Floodplain Ecosystems Research Station,Department of Life Sciences,Henan University,Jinming Avenue,Kaifeng,Henan 475001,People’s Republic of China [4]Department of Municipal and Environmental Engineering,Shenyang Jianzhu University,Shenyang 110168,People’s Republic of China

出　　处：《Journal of Forestry Research》2021年第5期2037-2045,共9页林业研究（英文版）

基　　金：the Key Research and Development Project from China’s Ministry of Science and Technology(2016YFA0600804);the National Natural Science Foundation of China[grant number 41575153,41430639,41673077,41675150 and 31800413]。

摘　　要：In addition to bacteria,the contribution of fungi to nitrous oxide(N_(2)O)production has been recognized but the responses of these two broad and unrelated groups of microorganisms to global environmental changes,atmospheric nitrogen(N)deposition,and precipitation in terms of N_(2)O production are unclear.We studied how these two microbial-mediated N_(2)O production pathways responded to soil moisture conditions and to N addition in an N-limited temperate forest.Soils from a long-term N addition experiment in Changbai Mountain,northeastern China were incubated.Varied concentrations of cycloheximide and streptomycin,both inhibitors of fungal and bacterial activity,were used to determine the contributions of both to N_(2)O production in 66%,98%and 130%water-filled pore spaces(WFPS).The results showed that N_(2)O production decreased significantly with increasing cycloheximide concentration whereas streptomycin was only inhibiting N_(2)O emissions at 98%and 130%WFPS.The bacterial pathway of N_(2)O production in N-addition(Nadd)soil was significantly more dominant than that in untreated(Namb)soil.The difference in the fungal pathway of N_(2)O production between the soil with nitrogen addition and the untreated soil was not significant.Net N_(2)O emissions increased with increasing soil moisture,especially at 130%WFPS,a completely flooded condition.Bacteria dominated carbon dioxide(CO_(2))and N_(2)O emissions in Nadd soil and at 130%WFPS regardless of N status,while fungi dominated CO_(2)and N_(2)O emissions in soil without N addition at 66%and 98%WFPS.The results suggest that flooded soil is an important source of N_(2)O emissions and that bacteria might be better adapted to compete in fertile soils under anoxic conditions.

关 键 词：Nitrous oxide FUNGI BACTERIA Nitrogen addition Soil moisture conditions 

分 类 号：S714[农业科学—林学]