Impact of nitrogen addition on plant-soil-enzyme C–N–P stoichiometry and microbial nutrient limitation

• Published in: Soil biology & biochemistry 2022-07, Vol.170, p.108714, Article 108714
• Main Authors: Xu, Hongwei, Qu, Qing, Li, Guanwen, Liu, Guobin, Geissen, Violette, Ritsema, Coen J., Xue, Sha
• Format: Article
• Language: English
• Subjects: Ecological stoichiometry; Meta-analysis; Nitrogen deposition; Plant-soil-microbial; Soil chemistry; Soil microbial activity
• ISSN: 0038-0717; 1879-3428
• DOI: 10.1016/j.soilbio.2022.108714

Global atmospheric nitrogen deposition significantly affects the nutrient cycling and C–N–P stoichiometry in ecosystems. Herein, a global meta-analysis was conducted based on 898 pairwise observations to analyze the impact of nitrogen addition on plant-soil-enzyme C–N–P stoichiometry and microbial nutrient limitation in different ecosystem types (cropland, grassland, and forest), nitrogen addition intensity (0–5, 5–10, and >10 g N m−2 yr−1) and duration (0–5, 5–10, and >10yr). Results showed that nitrogen addition significantly decreased plant C:N (shoot: 16.5%, root: 27.1%, litter: 16.5%), soil C:N (5.9%), enzyme C:P (1.2%), and enzyme N:P (5.1%), whereas significantly increased soil C:P (4.9%), enzyme C:N (7.1%), vector angle (4.4%), vector length (3.9%), and plant N:P (shoot: 24.1%, root: 23.8%, and litter: 13.5%). Furthermore, nitrogen addition mainly affected the enzyme C:N and vector length in grasslands. Additionally, the changes in C:N in plants, soil, and enzymes, and vector angle and length were higher at nitrogen addition intensity of >10 g N m−2 yr−1. The changes in C:N and C:P in plant and soil were higher at nitrogen addition duration of >10 yr. Finally, the N:P in shoot, soil and enzyme, and vector angle were strongly correlated with mean annual precipitation (MAP). In conclusion, nitrogen addition significantly reduced the C:N ratio in plants and soil and increased plant N:P, and microbial C and P limitation. These effects vary with the ecosystem type, MAP, and nitrogen addition intensity and duration. The results improve our understanding of the plant-soil-microbial nutrient cycling processes in terrestrial ecosystems under global nitrogen deposition. [Display omitted] •N addition reduced soil and plant C:N and increased plant N:P.•N addition increased microbial C limitation in grassland and P limitation in forests.•N addition intensity and duration weakened microbial P limitation.•Results help to understand terrestrial geochemical cycle under N deposition.