文献类型：期刊文献

英文题名：Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu Gulf

作者：He, Qing[1];Chen, Qingxiang[1];Qin, Xinyi[2];Zhou, Shengyao[3];Nethmini, Rajapakshalage Thashikala[1];Jiang, Gonglingxia[1];Hou, Qinghua[1];Li, Xiaolei[1];Huang, Laizhen[1];Dong, Ke[4];Xie, Lingling[1];Li, Nan[1]

机构：[1]Guangdong Ocean Univ, Coll Ocean & Meteorol,Dept Oceanog, Key Lab Climate Resources & Environm Continental S, Dept Educ Guangdong Prov,Key Lab Coastal Ocean Var, Zhanjiang, Peoples R China;[2]Nanning Normal Univ, Key Lab Environm Change & Resources Use Beibu Gulf, Minist Educ, Nanning, Peoples R China;[3]Guilin Univ Technol, Coll Environm Sci & Engn, Guilin, Peoples R China;[4]Kyonggi Univ, Dept Biol Sci, Suwonsi, South Korea

年份：2025

卷号：16

外文期刊名：FRONTIERS IN MICROBIOLOGY

收录：SCI-EXPANDED(收录号：WOS:001524383400001)、、Scopus(收录号：2-s2.0-105010877097)、WOS

基金：The author(s) declare that financial support was received for the research and/or publication of this article. This research was jointly funded by the Guangdong Ocean University Innovative Team (Early-warning of marine disasters) (Grant number 2023KCXTD015); Guangxi Key Research and Development Program (Grant number AB24010109); the Scientific Research Start Funds of Guang dong Ocean University; the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (RS-2022-NR073058).

语种：英文

外文关键词：bacterial communities; co-occurrence network; community stability; community complexity; environmental threshold

外文摘要：Environmental gradients are important for bacteria community in marine ecosystems. However, the tipping points of environmental heterogeneity and ecological responses to disturbances in marine ecosystems are still unclear. In this study, we sampled seawater from different layers of Beibu Gulf to investigate bacterial composition, diversity, network complexity and stability, and environmental thresholds. Proteobacteria (40.38%), Cyanobacteria (27.35%), and Actinobacteria (18.24%) were dominant across all three layers. Alpha diversity was higher in the bottom layer (BL), and beta diversity were greater in the middle layer (ML). Deterministic processes significantly structured bacterial communities. The BL had the most complex network, while the ML showed the highest stability. Dissolved oxygen (DO) influenced bacterial dissimilarity and community stability, while NO3- drives complexity. Segmented regression identified environmental stress thresholds: pH = 7.79, TN = 7.48 mg/L, and temperature = 27.9 degrees C. DO thresholds for beta diversity were 6.31 mg/L, 6.25 mg/L and 5.93 mg/L across layers, and for beta NTI were 6.57 mg/L and 6.24 mg/L in ML and BL. Tipping points for community stability occurred at DO levels of 6.71 mg/L, 5.80 mg/L and 5.94 mg/L. NO3- thresholds of complexity appeared in the SL (at 0.003 mg/L) and BL (0.020 mg/L) samples, but not in ML. This study provides new insights into bacterial stress resistance and community maintenance in the subtropical Gulf marine environments.