Environmental Microbiomics Research Center, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, and the School of Environmental Science and Engineering, Sun Yat-sen University, 132 East Circle, University Town, Guangzhou, 510006, China.
Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
Microb Ecol. 2019 Feb;77(2):277-287. doi: 10.1007/s00248-018-1222-0. Epub 2018 Jun 27.
Bacterioplankton are both primary producers and primary consumers in aquatic ecosystems, which were commonly investigated to reflect environmental changes, evaluate primary productivity, and assess biogeochemical cycles. However, there is relatively less understanding of their responses to anthropogenic disturbances such as constructions of dams/tunnels/roads that may significantly affect the aquatic ecosystem. To fill such gap, this study focused on the bacterioplankton communities' diversity and turnover during a tunnel construction across an urban lake (Lake Donghu, Wuhan, China), and five batches of samples were collected within 2 months according to the tunnel construction progress. Results indicated that both resources and predator factors contributed significant to the variations of bacterioplankton communities, but the closed area and open areas showed different diversity patterns due to the impacts of tunnel construction. Briefly, the phytoplankton, TN, and TP in water were still significantly correlated with the bacterioplankton composition and diversity like that in normal conditions. Additionally, the organic matter, TN, and NH-N in sediments also showed clear effects on the bacterioplankton. However, the predator effects on the bacterioplankton in the closed-off construction area mainly derived from large zooplankton (i.e., cladocerans), while small zooplankton such as protozoa and rotifers are only responsible for weak predator effects on the bacterioplankton in the open areas. Further analysis about the ecological driving forces indicated that the bacterioplankton communities' turnover during the tunnel construction was mainly governed by the homogeneous selection due to similar environments within the closed area or the open areas at two different stages. This finding suggests that bacterioplankton communities can quickly adapt to the environmental modifications resulting from tunnel construction activities. This study can also give references to enhance our understanding on bacterioplankton communities' response to ecological and environmental changes due to intensification of construction and urbanization in and around lake ecosystems.
浮游细菌既是水生生态系统中的初级生产者也是初级消费者，通常用于反映环境变化、评估初级生产力和评估生物地球化学循环。然而，对于它们对人为干扰（如大坝/隧道/道路建设）的响应，人们的了解相对较少，这些干扰可能会对水生生态系统产生重大影响。为了填补这一空白，本研究聚焦于隧道建设过程中浮游细菌群落的多样性和演替，该隧道穿过中国武汉市东湖，在 2 个月内根据隧道建设进度采集了 5 批样本。结果表明，资源和捕食者因素都对浮游细菌群落的变化有显著贡献，但由于隧道建设的影响，封闭区和开放区的多样性模式不同。简而言之，水中的浮游植物、总氮和总磷与正常条件下的浮游细菌组成和多样性仍然显著相关。此外，沉积物中的有机物、总氮和氨氮也对浮游细菌有明显的影响。然而，在封闭施工区，捕食者对浮游细菌的影响主要来自大型浮游动物（如桡足类），而小型浮游动物（如原生动物和轮虫）仅对开放区浮游细菌的弱捕食者效应负责。对生态驱动力的进一步分析表明，隧道施工期间浮游细菌群落的演替主要受同质选择的控制，因为封闭区或两个不同阶段的开放区内部环境相似。这一发现表明，浮游细菌群落可以迅速适应隧道建设活动导致的环境变化。本研究还可以为增强我们对由于湖泊生态系统及其周围地区的建设和城市化加剧而导致的浮游细菌群落对生态和环境变化的响应的理解提供参考。
