第一作者：崔晓宇 副研究员（天津大学）
通讯作者：童银栋 教授（天津大学/西藏大学）
论文DOI: 10.1016/j.watres.2019.06.017
温度、光照和营养条件对铜绿微囊藻的生长和产毒的影响
Fig. 1. Impacts of temperature (a), light (b), nitrate (c) and phosphate (d) enrichments on the cell density of Microcystis aeruginosa under mono-culture. The bars represent the mean ± standard deviation of three independent replicates. Copyright 2024, Elsevier Inc.
在不同温度、光照强度和营养水平条件下，Microcystis aeruginosa的生物量先增加后趋于稳定，其中提高水温和营养浓度显著促进了其生长。此外，实验还观察到在较高光照强度下，Microcystis aeruginosa的生物量增长受到限制，可能是由于营养物质的耗尽。
Fig. 2. IMCs (a-d) and EMCs (e-h) per cell at different temperature, light irradiation, nitrate and phosphate enrichments under mono-culture. The bars represent the mean ± standard deviation of three independent replicates. Different letters indicate statistically distinguishable observations (ANOVA, P < 0.05). An asterisk indicates the significant difference between the sample collected at Day 6 and 12 (t-test, P < 0.05). Copyright 2024, Elsevier Inc.
Chlorella sp.对Microcystis aeruginosa生长和产毒的影响
Fig. 3. Specific growth rates of Microcystis aeruginosa(a) and Chlorella sp. (b) at different temperature, light, nitrate and phosphate conditions (left axis), as well as the corresponding differences of the specific growth rates between mixed culture and mono-culture (right axis). The bars represent the mean ± standard deviation of three independent replicates. An asterisk indicates the significant difference between the sample collected at Day 6 and 12 (t-test, P < 0.05). Copyright 2024, Elsevier Inc.
在混合培养中，Microcystis aeruginosa的生长速率在多种环境条件下均高于Chlorella sp.，表明Microcystis aeruginosa在竞争中占据优势。通过运用Lotka-Volterra模型，研究揭示了两种藻类之间的竞争系数，发现Chlorella sp.对Microcystis aeruginosa的生长起到了促进作用，而Microcystis aeruginosa则抑制了Chlorella sp.的生长。此外，环境因素如温度、光照、氮和磷浓度对这两种藻类的竞争能力有显著影响。
Fig. 4. Comparison of IMCs between mono-culture and mixed culture (a), redundancy analysis (RDA) of IMCs and biomass of Microcystis aeruginosa and Chlorella sp. (b), as well as the Venn diagram of the interactive information of the four variables on IMC production under mono-culture (c) and mixed culture (d). In the figure, “M” denotes the biomass of Microcystis aeruginosa, “C” represents the biomass of Chlorellasp., “T” indicates temperature, “L” stands for light exposure, “N” signifies the consumption of nitrate, and “P” denotes the consumption of phosphate. An asterisk indicates the significant difference between mono-culture and mixed culture (t-test, P < 0.05). Copyright 2024, Elsevier Inc.
在与Chlorella sp.的种间竞争中，Microcystis aeruginosa的毒素产生受到环境因素和竞争强度的共同影响。结果表明当Microcystis aeruginosa面临来自Chlorella sp.的竞争压力时，其毒素产生量增加，这可能是作为一种生态适应策略来获取更多的生态位和资源。此外，不同环境因素及其交互作用对毒素产生的贡献差异揭示了种间竞争在调节毒素产量中的重要作用。
Fig. 5. Relationship between competitive inhibition coefficients α (a) and β (b) with difference in IMC concentrations under mixed culture conditions versus mono-culture conditions. The bars represent the mean ± standard deviation of three independent replicates. Copyright 2024, Elsevier Inc.
随着Chlorella sp.对Microcystis aeruginosa的竞争抑制增强，Microcystis aeruginosa的毒素产生也随之增加，表明Microcystis aeruginosa通过增加毒素应对竞争压力。同时，Microcystis aeruginosa自身的竞争抑制作用先抑制后促进了毒素的产生，这可能与抵御Chlorella sp.释放的化感物质有关。这说明种间竞争是Microcystis aeruginosa毒素合成的重要调节因素。
研究突出显示，提高的温度和营养水平显著促进了Microcystis aeruginosa的生长，而在竞争条件下，Chlorella sp.的存在则进一步增强了Microcystis aeruginosa的微囊藻毒素生产。研究发现，在种间竞争期间，营养水平对毒素产生的贡献超过了温度因素，并且种间竞争的强度与微囊藻毒素的增加密切相关。这些结果强调了在未来的毒素风险评估中需要考虑种间竞争的影响。
童银栋 英才教授、博士生导师，现任职于天津大学环境科学与工程学院。国家优秀青年科学基金获得者、中组部第十批援藏干部人才、国家优秀青年科学基金获得者、天津市课程思政教学名师、天津大学北洋学者；聚焦氮、磷、汞等关键元素在流域尺度的输移过程和河湖水体的环境效应研究。近五年来，以第一或通讯作者在Nature Geoscience、PNAS、ES&T、Water Research等领域内顶级期刊发表SCI论文80余篇；获中国环境学会青年科学家奖、天津市优秀青年科技工作者、天津大学教育育人先进工作者等多项荣誉。
Permissions for reuse of all Figures have been obtained from the original publisher. Copyright 2024, Elsevier Inc
参考文献：
Cui, X.; Yang, N.; Cui, H.; Yang, Q.; Wu, Z.; Shao, B.; Zhao, Y.; Tong, Y. Interspecific Competition Enhances Microcystin Production by Microcystis Aeruginosa under the Interactive Influences of Temperature and Nutrients. Water Res 2024, 265, 122308
https://www.sciencedirect.com/science/article/abs/pii/S0043135424012077
