Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Institute of Environmental Research at Greater Bay Area, Guangzhou University, Guangzhou, 510006, China.
School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, China.
Curr Microbiol. 2022 Aug 16;79(10):289. doi: 10.1007/s00284-022-02982-7.
Denitrifying bacteria, playing a key role in nitrogen removal in ecosystem, are highly diverse and complex in their community composition. However, there were few reports on the abundance, community composition, and the contribution to nitrogen loss of denitrifiers in natural acidic red soils. In this study, we investigated the structure and function of nirS-type denitrifying bacteria in ten natural red soil samples collected from nine provinces in southern China, based on quantitative polymerase chain reaction (qPCR) and high-throughput sequencing techniques. Nitrogen loss from microbial denitrification in red soils of southern China was estimated up to 9.86 Tg N per year based on N isotope tracing method. The abundance of nirS-type denitrifiers varied from 8.41 × 10 to 2.55 × 10 copies per gram of dry weight. The community of nirS-type denitrifying bacterial was revealed, which contained 50 dominant OTUs assigned to 9 clusters phylogenetically related to Marinobacter, Rhodobacter, and other uncultured species. pH was the key factor affecting both denitrification rates and community composition. Our results demonstrate that nirS-type denitrifying bacteria have higher abundance, diversity, and contribution to the nitrogen loss in natural acidic red soils of southern China.
反硝化细菌在生态系统的氮去除中起着关键作用，其群落组成高度多样和复杂。然而，关于自然酸性红壤中反硝化菌的丰度、群落组成及其对氮损失的贡献，报道较少。本研究采用定量聚合酶链反应（qPCR）和高通量测序技术，对中国南方 9 个省的 10 个天然红土样本中的 nirS 型反硝化细菌的结构和功能进行了研究。基于氮同位素示踪法，估计中国南方红土中微生物反硝化导致的氮损失高达 9.86TgN/年。nirS 型反硝化菌的丰度变化范围为 8.41×10至 2.55×10拷贝/克干重。揭示了 nirS 型反硝化细菌的群落组成，包含 50 个优势 OTUs，它们在系统发育上与 Marinobacter、Rhodobacter 和其他未培养的物种有关。pH 是影响反硝化速率和群落组成的关键因素。本研究结果表明，nirS 型反硝化细菌在我国南方自然酸性红壤中具有更高的丰度、多样性和对氮损失的贡献。
