Bacterioplankton assembly and interspecies interaction indicating increasing coastal eutrophication.
Anthropogenic perturbations impose negative effects on coastal ecosystems, such as increasing levels of eutrophication. Given the biogeochemical significance of microorganisms, understanding the processes and mechanisms underlying their spatial distribution under changing environmental conditions is critical. To address this question, we examined how coastal bacterioplankton communities respond to increasing eutrophication levels created by anthropogenic perturbations. The results showed that the magnitude of changes in the bacterioplankton community compositions (BCCs) and the importance of deterministic processes that constrained bacterial assembly were closely associated with eutrophication levels. Moreover, increasing eutrophication significantly (P < 0.001) attenuated the distance decay rate, with a random spatial distribution of BCCs in the undisturbed location. In contrast, the complexity of interspecies interaction was enhanced under moderate eutrophication levels but declined under heavy eutrophication. Changes in the relative abundances of 27 bacterial families were significantly correlated with eutrophication levels. Notably, the pattern of enrichment or decrease for a given bacterial family was consistent with its known ecological functions. Our findings demonstrate that the magnitude of changes in BCCs and underlying determinism are dependent on eutrophication levels. However, the buffer capacity of bacterioplankton community is limited, with disrupted interspecies interaction occurring under heavy eutrophication. As such, bacterial assemblages are sensitive to changes in environmental conditions and could thus potentially serve as bio-indicators for increasing eutrophication.
School of Marine Sciences, Ningbo University, Ningbo, 315211, China; Collaborative Innovation Center for Zhejiang Marine High-Efficiency and Healthy Aquaculture, Ningbo, 315211, China.
Wenfang
W
Dai
School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
Jinjie
J
Zhang
Department of Marine Sciences, Ocean College, Zhejiang University, Hangzhou, 310058, China.
Qichao
Q
Tu
Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, CAS, Beijing, 100085, China.
Ye
Y
Deng
School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
Qiongfen
Q
Qiu
School of Marine Sciences, Ningbo University, Ningbo, 315211, China; Collaborative Innovation Center for Zhejiang Marine High-Efficiency and Healthy Aquaculture, Ningbo, 315211, China. Electronic address: xiongjinbo@nbu.edu.cn.
Jinbo
J
Xiong
D059001:Aquatic Organisms; D001419:Bacteria; D002681:China; D004275:DNA, Ribosomal; D004463:Ecology; D017753:Ecosystem; D005068:Eutrophication; D010933:Plankton / Q000502:physiology*; D045483:Rivers; D012623:Seawater; D017422:Sequence Analysis, DNA
D004275:DNA, Ribosomal
BCCs; Bio-indicators; Coastal eutrophication; Deterministic processes; Interspecies interaction; Spatial distribution