Watanabe Shunsuke, Matsunami Naoki, Okuma Ikki, Naythen Podiapen Tannen, Fujibayashi Megumu, Iseri Yasushi, Hao Aimin, Kuba Takahiro
Department of Urban and Environmental Engineering, Kyushu University, Fukuoka, Japan.
Central Water Authority Head Office, Phoenix, Mauritius.
Water Environ Res. 2022 Apr;94(4):e10707. doi: 10.1002/wer.10707.
Lake eutrophication is associated with cyanobacterial blooms. The pennate diatom Nitzschia palea (N. palea) inhibits the growth of the cyanobacterium Microcystis aeruginosa (M. aeruginosa); therefore, increasing the relative abundance of N. palea may contribute to the inhibition of Microcystis blooms. Several studies have demonstrated that blue light irradiation promotes diatom growth and inhibits cyanobacterial growth. In this study, we evaluated the effects of blue light irradiation on N. palea and M. aeruginosa abundance. Monocultures and co-cultures of N. palea and M. aeruginosa were exposed to blue light and fluorescent light at 32 μmol photons m s. The relative abundance of N. palea under fluorescent light decreased gradually, whereas the abundance under blue light was relatively higher (approximately 74% and 98% under fluorescent light and blue light, respectively, at the end of the experiment). The inhibition efficiency of blue light on the growth rate of M. aeruginosa was related to the light intensity. The optimal light intensity was considered 20 μmol photons m s based on the inhibition efficiency of 100%. Blue light irradiation can be used to increase the abundance of N. palea to control Microcystis blooms. PRACTITIONER POINTS: The effects of blue light irradiation on N. palea abundance was discussed. Monocultures and co-cultures of N. palea and M. aeruginosa were exposed to blue light and to fluorescent light. The relative abundance of N. palea increased upon irradiation with blue light in co-culture with M. aeruginosa.
湖泊富营养化与蓝藻水华有关。羽纹硅藻微小菱形藻（Nitzschia palea，N. palea）可抑制铜绿微囊藻（Microcystis aeruginosa，M. aeruginosa）的生长；因此，提高N. palea的相对丰度可能有助于抑制微囊藻水华。多项研究表明，蓝光照射可促进硅藻生长并抑制蓝藻生长。在本研究中，我们评估了蓝光照射对N. palea和M. aeruginosa丰度的影响。将N. palea和M. aeruginosa的单培养物和共培养物置于32 μmol光子·m⁻²·s⁻¹的蓝光和荧光下。荧光下N. palea的相对丰度逐渐降低，而蓝光下的丰度相对较高（实验结束时，荧光下和蓝光下分别约为74%和98%）。蓝光对M. aeruginosa生长速率的抑制效率与光强有关。基于100%的抑制效率，最佳光强为20 μmol光子·m⁻²·s⁻¹。蓝光照射可用于增加N. palea的丰度以控制微囊藻水华。从业者要点：讨论了蓝光照射对N. palea丰度的影响。将N. palea和M. aeruginosa的单培养物和共培养物置于蓝光和荧光下。在与M. aeruginosa共培养时，蓝光照射使N. palea的相对丰度增加。
