Title: Long-term nitrogen fertilization decreases bacterial diversity and favors the growth of Actinobacteria and Proteobacteria in agro-ecosystems across the globe

Abstract

Long-term Elevated nitrogen (N) input from anthropogenic sources may cause soil acidification and decrease crop yield, yet the response of the belowground microbial community to long-term N input and the input of N combined with phosphorus (P) and potassium (K) is still poorly understood. Here, we explored the effect of long-term N and NPK fertilization on soil bacterial diversity and community composition using meta-analysis of a global dataset. Nitrogen fertilization decreased soil pH, and increased soil organic carbon (C) and available N contents. Bacterial taxonomic diversity was decreased by N fertilization alone, but was increased by NPK fertilization. The effect of N fertilization on bacterial diversity depends on soil texture and water management, but independent of crop type or N application rate. Both soil pH and organic C content were positively related to changes in bacterial diversity under N fertilization, while soil organic C was the dominant factor determining changes in bacterial diversity under NPK fertilization. Microbial biomass C decreased with decreasing bacterial diversity under long-term N fertilization. Nitrogen fertilization increased the relative abundance of copiotrophic bacteria (i.e. Proteobacteria and Actinobacteria), but reduced the abundance of oligotrophic taxa (i.e. Acidobacteria), consistent with the general life history strategy theory for bacteria.more » The relative abundance of Proteobacteria was also increased by NPK fertilization. The positive correlation between N application rate and the relative abundance of Actinobacteria indicates that increased N availability favored the growth of Actinobacteria. This first global analysis of long-term N and NPK fertilization effect on bacterial diversity and community composition suggests that N input decreases bacterial diversity but favors the growth of copiotrophic bacteria, providing a reference for nutrient management strategies for maintaining belowground microbial diversity in agro-ecosystems worldwide.« less

Authors:

Dai, Zhongmin ^[1]; Su, Weiqin ^[1]; Chen, Huaihai ^[2]; Barberán, Albert ^[3]; Zhao, Haochun ^[1]; Yu, Mengjie ^[1]; Yu, Lu ^[1]; Brookes, Philip C. ^[1]; Schadt, Christopher W.  ^[2];

• Search DOE PAGES for author "Schadt, Christopher W."
• Search DOE PAGES for ORCID "0000-0001-8759-2448"

Chang, Scott X. ^[4]; Xu, Jianming  ^[1]

• Search DOE PAGES for author "Xu, Jianming"
• Search DOE PAGES for ORCID "0000-0002-2954-9764"

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+ Show Author Affiliations

1. Zhejiang Univ., Hangzhou (China). Zhejiang Provincial Key Lab. of Agricultural Resources and Environment, Inst. of Soil and Water Resources and Environmental Science
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
3. Univ. of Arizona, Tucson, AZ (United States)
4. Univ. of Alberta, Edmonton, AB (Canada)

Publication Date:

Thu Apr 12 00:00:00 EDT 2018

Research Org.:

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE; National Basic Research Program of China; National Natural Science Foundation of China (NSFC)

OSTI Identifier:

1435246

Grant/Contract Number:  

AC05-00OR22725; 2014CB441003

Resource Type:

Accepted Manuscript

Journal Name:

Global Change Biology

Additional Journal Information:

Journal Volume: 24; Journal Issue: 8; Journal ID: ISSN 1354-1013

Publisher:

Wiley

Country of Publication:

United States

Language:

English

Subject:

59 BASIC BIOLOGICAL SCIENCES; N fertilization; bacterial diversity; community composition; microbial biomass; Actinobacteria; agro-ecosystems