Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu Gulf

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 inv...

Full description

Saved in:
Bibliographic Details
Main Authors: Qing He, Qingxiang Chen, Xinyi Qin, Shengyao Zhou, Rajapakshalage Thashikala Nethmini, Gonglingxia Jiang, Qinghua Hou, Xiaolei Li, Laizhen Huang, Ke Dong, Lingling Xie, Nan Li
Format: Article
Language:English
Published: Frontiers Media S.A. 2025-06-01
Series:Frontiers in Microbiology
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fmicb.2025.1622150/full
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849434708008501248
author Qing He
Qingxiang Chen
Xinyi Qin
Shengyao Zhou
Rajapakshalage Thashikala Nethmini
Gonglingxia Jiang
Qinghua Hou
Xiaolei Li
Laizhen Huang
Ke Dong
Lingling Xie
Nan Li
author_facet Qing He
Qingxiang Chen
Xinyi Qin
Shengyao Zhou
Rajapakshalage Thashikala Nethmini
Gonglingxia Jiang
Qinghua Hou
Xiaolei Li
Laizhen Huang
Ke Dong
Lingling Xie
Nan Li
author_sort Qing He
collection DOAJ
description 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°C. DO thresholds for beta diversity were 6.31 mg/L, 6.25 mg/L and 5.93 mg/L across layers, and for βNTI 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.
format Article
id doaj-art-cb7ecef0547e463ca80fa165f378268e
institution Kabale University
issn 1664-302X
language English
publishDate 2025-06-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Microbiology
spelling doaj-art-cb7ecef0547e463ca80fa165f378268e2025-08-20T03:26:34ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2025-06-011610.3389/fmicb.2025.16221501622150Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu GulfQing He0Qingxiang Chen1Xinyi Qin2Shengyao Zhou3Rajapakshalage Thashikala Nethmini4Gonglingxia Jiang5Qinghua Hou6Xiaolei Li7Laizhen Huang8Ke Dong9Lingling Xie10Nan Li11Key Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaKey Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaKey Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education (Nanning Normal University), Nanning, ChinaCollege of Environmental Science and Engineering, Guilin University of Technology, Guilin, ChinaKey Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaKey Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaKey Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaKey Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaKey Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaDepartment of Biological Sciences, Kyonggi University, Suwon-si, Republic of KoreaKey Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaKey Laboratory of Climate, Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong Province, Department of Oceanography, Key Laboratory for Coastal Ocean Variation and Disaster Prediction, College of Ocean and Meteorology, Guangdong Ocean University, Zhanjiang, ChinaEnvironmental 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°C. DO thresholds for beta diversity were 6.31 mg/L, 6.25 mg/L and 5.93 mg/L across layers, and for βNTI 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.https://www.frontiersin.org/articles/10.3389/fmicb.2025.1622150/fullbacterial communitiesco-occurrence networkcommunity stabilitycommunity complexityenvironmental threshold
spellingShingle Qing He
Qingxiang Chen
Xinyi Qin
Shengyao Zhou
Rajapakshalage Thashikala Nethmini
Gonglingxia Jiang
Qinghua Hou
Xiaolei Li
Laizhen Huang
Ke Dong
Lingling Xie
Nan Li
Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu Gulf
Frontiers in Microbiology
bacterial communities
co-occurrence network
community stability
community complexity
environmental threshold
title Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu Gulf
title_full Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu Gulf
title_fullStr Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu Gulf
title_full_unstemmed Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu Gulf
title_short Dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in Beibu Gulf
title_sort dissolved oxygen and nitrates gradient influence marine microbial complexity and stability in beibu gulf
topic bacterial communities
co-occurrence network
community stability
community complexity
environmental threshold
url https://www.frontiersin.org/articles/10.3389/fmicb.2025.1622150/full
work_keys_str_mv AT qinghe dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT qingxiangchen dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT xinyiqin dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT shengyaozhou dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT rajapakshalagethashikalanethmini dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT gonglingxiajiang dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT qinghuahou dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT xiaoleili dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT laizhenhuang dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT kedong dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT linglingxie dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf
AT nanli dissolvedoxygenandnitratesgradientinfluencemarinemicrobialcomplexityandstabilityinbeibugulf