Relative contributions of different substrates to soil N2O emission and their responses to N addition in a temperate forest

被引：8

作者：

Peng, Bo ^{[1
,2
]}

Sun, Jianfei ^{[1
,3
]}

Liu, Jun ^{[1
]}

Xia, Zongwei ^{[1
]}

Dai, Weiwei ^{[1
]}

机构：

[1] Chinese Acad Sci, Inst Appl Ecol, CAS Key Lab Forest Ecol & Management, Shenyang 110016, Peoples R China

[2] Yichun Univ, Coll Life Sci & Resources & Environm, Yichun 336000, Peoples R China

[3] Nanning Normal Univ, Guangxi Key Lab Earth Surface Proc & Intelligent, Minist Educ, Key Lab Environm Change & Resources Use Beibu Gul, Nanning 530001, Peoples R China

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2021年 / 767卷

基金：

中国国家自然科学基金;

关键词：

N deposition; N tracer; N2O emission; Autotrophic nitrification; Heterotrophic nitrification; Denitrification; Functional genes; AMMONIA-OXIDIZING ARCHAEA; REDUCTASE GENES NIRK; NITROUS-OXIDE; HETEROTROPHIC NITRIFICATION; DENITRIFYING BACTERIA; NITRIFIER DENITRIFICATION; PRODUCTION PATHWAYS; NOSZ GENES; ECOSYSTEMS; DIVERSITY;

D O I：

10.1016/j.scitotenv.2020.144126

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

With increasing nitrogen (N) deposition, soil nitrous oxide (N2O) emission is expected to increase, causing positive feedback to global warming. However, the substrates of soil N2O emission, especially their responses to N addition, are still unclear. Here, we conducted an in situ N-15 tracing experiment to study the substrates of N2O (i.e., ammonium-derived, nitrate-derived and organic N-derived N2O emission) under N addition treatment in a temperate forest in northeast China. Nitrate derived N2O through denitrification contributed most to the total N2O emission, pointing to the importance of denitrilication under ambient N deposition. NH4NO3 addition of 50 kg N ha(-1) yr(-1) significantly increased organic N derived N2O on the 6th day after N addition, which suggests that heterotrophic nitrification may be the dominating process with higher N deposition rate. However, because soil pH and the examined functional genes did not change after N addition, future studies should be carried out to understand if the increase of heterotrophic nitrification is transient. Our study emphasizes the role of organic N pool in soil N2O emissions, highlighting the importance of considering the heterotrophic nitrification process while studying soil N cycling or modeling soil N2O emission. (C) 2020 Elsevier B.V. All rights reserved.

引用

页数：8

共 91 条

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