Vital roles of soil microbes in driving terrestrial nitrogen immobilization

Zhaolei Li, Zhaoqi Zeng, Zhaopeng Song, Fuqiang Wang, Dashuan Tian, Wenhai Mi, Xin Huang, Jinsong Wang, Lei Song, Zhongkang Yang, Jun Wang, Haojie Feng, Lifen Jiang, Ye Chen, Yiqi Luo, Shuli Niu

Research output: Contribution to journalArticlepeer-review

14 Scopus citations

Abstract

Nitrogen immobilization usually leads to nitrogen retention in soil and, thus, influences soil nitrogen supply for plant growth. Understanding soil nitrogen immobilization is important for predicting soil nitrogen cycling under anthropogenic activities and climate changes. However, the global patterns and drivers of soil nitrogen immobilization remain unclear. We synthesized 1350 observations of gross soil nitrogen immobilization rate (NIR) from 97 articles to identify patterns and drivers of NIR. The global mean NIR was 8.77 ± 1.01 mg N kg−1 soil day−1. It was 5.55 ± 0.41 mg N kg−1 soil day−1 in croplands, 15.74 ± 3.02 mg N kg−1 soil day−1 in wetlands, and 15.26 ± 2.98 mg N kg−1 soil day−1 in forests. The NIR increased with mean annual temperature, precipitation, soil moisture, soil organic carbon, total nitrogen, dissolved organic nitrogen, ammonium, nitrate, phosphorus, and microbial biomass carbon. But it decreased with soil pH. The results of structural equation models showed that soil microbial biomass carbon was a pivotal driver of NIR, because temperature, total soil nitrogen, and soil pH mostly indirectly influenced NIR via changing soil microbial biomass. Moreover, microbial biomass carbon accounted for most of the variations in NIR among all direct relationships. Furthermore, the efficiency of transforming the immobilized nitrogen to microbial biomass nitrogen was lower in croplands than in natural ecosystems (i.e., forests, grasslands, and wetlands). These findings suggested that soil nitrogen retention may decrease under the land use change from forests or wetlands to croplands, but NIR was expected to increase due to increased microbial biomass under global warming. The identified patterns and drivers of soil nitrogen immobilization in this study are crucial to project the changes in soil nitrogen retention.

Original languageEnglish (US)
Pages (from-to)1848-1858
Number of pages11
JournalGlobal change biology
Volume27
Issue number9
DOIs
StatePublished - May 2021

Keywords

  • croplands
  • global change
  • microbial biomass
  • nitrogen immobilization
  • soil nitrogen retention

ASJC Scopus subject areas

  • Global and Planetary Change
  • Environmental Chemistry
  • Ecology
  • Environmental Science(all)

Fingerprint

Dive into the research topics of 'Vital roles of soil microbes in driving terrestrial nitrogen immobilization'. Together they form a unique fingerprint.

Cite this