Nitrogen cycling and functional gene diversity of drinking reservoir area in agricultural districts: Implications for nitrogen transformation processes

作者：Mengze Li, Wenwen Wang, Shengwu Yuan, Kun Wang, Shuhang Wang, Weidong Li, Xia Jiang, Wenqiang Zhang, Baoqing Shan · 发表于：Ecological Indicators · 年份：2025 · DOI：10.1016/j.ecolind.2025.113349 · 被引用次数：9 · 研究领域：Wastewater Treatment and Nitrogen Removal、Constructed Wetlands for Wastewater Treatment、Soil and Water Nutrient Dynamics

• Nitrogen cycling in an agricultural reservoir was analyzed using metagenomics. • ANRA and denitrification drive nitrogen processes in water, sediments favor fixation. • Environmental factors strongly influence nitrogen functional gene distribution. • Reservoir sediments act as nitrogen sinks, regulating water column nitrogen levels. Nitrogen pollution in aquatic ecosystems, especially in shallow lakes and reservoirs, has intensified in recent years due to human activities like agricultural fertilization and wastewater discharge. However, the microbial mechanisms driving nitrogen cycling are not well understood. This study examines nitrogen migration, transformation, and the microbial mechanisms driving nitrogen cycling in the QuanMin Reservoir, which is heavily influenced by agricultural activities and land runoff. The reservoir serves as a model for understanding nitrogen pollution, and its effects on water quality. The results indicate that total nitrogen (TN) concentrations in the overlying water ranged from 0.43 to 2.22 mg/L, with nitrate nitrogen accounting for an average of 52 % of the total. Nitrogen cycling was mainly driven by key genes involved in assimilatory nitrate reduction to ammonium and denitrification, with notable differences in gene abundance between river and reservoir waters. Denitrification genes were dominant in the sediments, and reservoir sediments showed a higher potential for nitrogen fixation than river sediments. Additionally, nitrate concentra...