Trophic regulation of soil microbial biomass under nitrogen enrichment: A global meta-analysis

Eutrophication, including nitrogen (N) enrichment, can affect soil microbial communities through changes in trophic interactions. However, a knowledge gap still exists about how plant resources (‘bottom-up effects’) and microbial predators (‘top-down effects’) regulate the impacts of N enrichment on microbial biomass at the global scale.
To address this knowledge gap, we conducted a global meta-analysis using 2885 paired observations from 217 publications to evaluate the regulatory effects of plant biomass and soil nematodes on soil microbial biomass under N enrichment across terrestrial ecosystems.
We found that the effects of N enrichment on soil microbial biomass strongly varied across ecosystems. N enrichment decreased the soil microbial biomass of natural grasslands and forests due to soil acidification and the subsequent losses of predatory and microbivorous nematodes stimulating microbial growth. By contrast, N enrichment increased the microbial biomass of managed croplands mainl..., We systematically searched all peer-reviewed studies on the effects of N enrichment on plant biomass, microbial biomass, and nematodes, using the Web of Science, Google Scholar, and the China National Knowledge Infrastructure Database (to 1st January, 2023). We used the following search string: (nitrogen addition OR nitrogen application OR nitrogen deposition OR nitrogen enrichment OR nitrogen fertilization OR nitrogen input OR nitrogen amendment) AND (fungi OR bacteria OR microbial biomass OR microbial community) AND (plant OR crop OR plant biomass OR above-ground biomass OR below-ground biomass OR root biomass OR yield OR nematod* OR fungivor* OR bacterivor* OR omnivor* OR predat* OR carnivor* OR nematode community OR nematode feeding groups OR bacterial-feeding nematode OR fungal-feeding nematode OR omnivorous nematode OR carnivorous nematode). The references listed in relevant previously published reviews and meta-analyses were also searched. In total, 207 studies from 217 publicati..., , **This README file was generated on 2024-01-12 by Wen Xing.**

**GENERAL INFORMATION**

1\. Title of Dataset: Trophic regulation of soil microbial biomass under nitrogen enrichment: A global meta-analysis.

2\. Author Information

   A. Principal Investigator Contact Information

Name: Xiaoming Lu

Institution: State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences

Address: Beijing, China

Email:

B. Associate or Co-investigator Contact Information

Name: Wen Xing

Institution: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences

Address: Beijing, China

Email:

3\. Date of data collection (single date, range, approximate date): 1998-2023.

4\. Geographic location of data collection: Global terrestrial ecosystems.

5\. Information about funding sources that supported the collection of the data: None.

**SHARING/ACCESS INFORMATION**

1\. Licenses/restrictions placed on the ...