Nitrogen Enrichment Regulates the Changes in Soil Aggregate-Associated Bacterial Community: Evidence from a Typical Temperate Forest

• Published in: Forests Vol. 15; no. 1; p. 77
• Main Authors: Lv, Wenwen, Liu, Yulin, Hai, Xuying, Liao, Yang, Li, Jiwei, Dong, Lingbo, Shangguan, Zhouping, Deng, Lei
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.01.2024
• Subjects: Aggregates; Bacteria; bacterial communities; Climate change; Community composition; community structure; Composition; Ecosystems; Enrichment; Environmental aspects; Environmental conditions; Forest soils; Habitats; Laboratories; Measurement; Nitrogen; Nitrogen content; Nitrogen enrichment; Nutrient content; Nutrients; Physicochemical properties; soil; Soil aggregates; Soil microbiology; Soil microorganisms; Soil properties; Soils; Temperate forests; China; Gansu China; Loess Plateau
• ISSN: 1999-4907; 1999-4907
• DOI: 10.3390/f15010077

The nitrogen (N) enrichment induced by atmospheric N deposition affects both soil physicochemical properties and bacterial communities. However, how N enrichment affects soil aggregate-associated bacterial communities remains largely unclear. In this study, we conducted a two-year N addition experiment (four N levels: 0, 5, 10, and 20 g N m−2 year−1, corresponding to normal N, low N, medium N, and high N, respectively) in a Quercus liaotungensis Koidz–dominated forest. The distribution, nutrient content, and bacterial community composition of the soil aggregates were measured under various N enrichment conditions. N enrichment changed the aggregate distribution, increased the content of nutrients in aggregates, and altered the aggregate-associated bacterial community composition. N enrichment reduced the complexity of the bacterial co-occurrence network and degraded the interactions between bacteria compared with those observed under the normal N level. Aggregate-associated bacterial community was determined to be primarily affected by N enrichment level but not by aggregate size. The litter properties are the key factors affecting the composition of bacteria in aggregates. These findings improve our understanding of aggregate-associated bacterial responses to N enrichment and the related influencing factors.