Mowing increased plant diversity but not soil microbial biomass under N-enriched environment in a temperate grassland

• Published in: Plant and soil Vol. 491; no. 1-2; pp. 205 - 217
• Main Authors: Ning, Qiushi, Jiang, Liangchao, Niu, Guoxiang, Yu, Qiang, Liu, Jushan, Wang, Ruzhen, Liao, Sha, Huang, Jianhui, Han, Xingguo, Yang, Junjie
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-10-2023; Springer; Springer Nature B.V
• Subjects: Agriculture; Analysis; Anthropogenic factors; Availability; Biodiversity; Biogeochemical cycles; Biological diversity; Biomass; Biomedical and Life Sciences; Carbon content; Copper; Cycles; Ecology; Enrichment; Grassland management; Grasslands; Life Sciences; Microorganisms; Mowing; Net Primary Productivity; Nitrogen; Nitrogen enrichment; Plant communities; Plant diversity; Plant Physiology; Plant Sciences; Plant species; Primary production; Properties; Regular Article; Soil improvement; Soil properties; Soil Science & Conservation; Soils; Species richness; China; Shannon-Weiner diversity; Nitrogen addition; Plant-microbe competition; Nutrient imbalance; Species richness
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-022-05332-5

Aims
The anthropogenic nitrogen (N) input has considerable consequences on soil microbial biomass, which is critical for biogeochemical cycling. As prevalent grassland management, mowing may reduce soil N storage, enhance plant biodiversity and soil microbial carbon (C) availability, all of which are important regulators of soil microbial biomass. However, convincing data is still scarce about how mowing affects soil microbial biomass under N enrichment.
Methods
The interactive effects of N addition (0 – 50 g N m
−2
 yr
−1
) and mowing (unmown vs. mown) on soil microbial biomass C (MBC) were measured by manipulating 6 years’ N addition experiment in Inner Mongolia grassland of China.
Results
Mowing increased soil inorganic N concentration, available Cu
2+
concentration, plant aboveground net primary production (ANPP), species richness, Shannon-Wiener biodiversity and ratio of fungal to bacterial biomass, and decreased soil available Mn
2+
concentration under N enrichment. Mowing also significantly reduced the dominance of
Leymus chinensis
. While mowing did not affect the soil MBC compared with that in only N added plots. The soil MBC was positively regulated by plant species richness and biodiversity, while was negatively regulated by ANPP, soil inorganic N, available Cu
2+
and Mn
2+
concentration in mown plots.
Conclusions
The results highlight that mowing cannot mitigate the negative effects of N enrichment on soil MBC. The soil, plant and microbial properties play important roles in regulating the response of soil MBC to mowing in N-enriched soil. This work improves the mechanistic understanding of the linkages between plant community and soil microbial C cycling.