State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China; School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China; School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
Sci Total Environ. 2020 Apr 1;711:134624. doi: 10.1016/j.scitotenv.2019.134624. Epub 2019 Nov 22.
The interaction and assembly processes of microeukaryotic community compositions (MECs) are rarely elucidated in environment with strong disturbance such as harmful algal blooms. To fill this gap, we analyzed changes of MECs induced by a diatom bloom using 18S rRNA gene amplicon sequencing. The MECs were mainly dominated by Cercozoa (average relative abundance, 49.2%), Diatom (25.5%) and Dinoflagellata (15.6%). MECs changed significantly (ANOSIM P < 0.01) in four-bloom stages. Environmental factors including pH, DO, nitrate and phosphate, together with bacterial communities could significantly influence the variation of MECs. Co-occurrence network analysis revealed a complex interaction between microeukaryotic and bacterial communities. Most OTUs in modules of the co-occurrence network were specific to one particular bloom stage. Phylogenetic based β-nearest taxon distance analyses revealed that stochastic processes mainly dominated microeukaryotic community assembly in the initial and after-bloom stage. However, microeukaryotic community assembly in middle and late stage of the bloom were driven by deterministic processes. In conclusion, both stochastic and deterministic processes play important roles in distinct bloom stages. These findings may expand current understandings of assembly mechanisms and microbial interactions underlying microeukaryotic dynamics in eutrophic aquatic ecosystems where harmful algal blooms occurred frequently.
真核微生物群落组成（MECs）的相互作用和组装过程在富营养化水体有害藻华等强干扰环境中很少被阐明。为了填补这一空白，我们使用 18S rRNA 基因扩增子测序分析了硅藻爆发引起的 MECs 变化。MECs 主要由肉足虫（平均相对丰度为 49.2%）、硅藻（25.5%）和甲藻（15.6%）主导。在四个藻华阶段，MECs 发生了显著变化（ANOSIM P < 0.01）。包括 pH、DO、硝酸盐和磷酸盐在内的环境因素以及细菌群落可以显著影响 MECs 的变化。共生网络分析揭示了真核微生物和细菌群落之间复杂的相互作用。共生网络模块中的大多数 OTUs 特定于一个特定的藻华阶段。基于系统发育的β最近分类单元距离分析表明，随机过程主要主导了初始和藻华后阶段的真核微生物群落组装。然而，藻华中期和后期的真核微生物群落组装则由确定性过程驱动。总之，随机和确定性过程在不同的藻华阶段都起着重要作用。这些发现可能会扩展当前对富营养化水生生态系统中有害藻华频繁发生的微生物动态背后的组装机制和微生物相互作用的理解。
