Cyanobacterial harmful algal blooms (cyanoHABs) are becoming increasingly common in aquatic ecosystems worldwide. However, their heterogeneous distributions make it difficult to accurately estimate the total algae biomass and forecast the occurrence of surface cyanoHABs by using traditional monitoring methods. Although various optical instruments and remote sensing methods have been employed to monitor the dynamics of cyanoHABs at the water surface (i.e., bloom area, chlorophyll ), there is no effective methodology to monitor the dynamic change of cell density and integrated biovolume of algae throughout the water column. In this study, we propose a quantitative protocol for simultaneously measurements of multiple indicators (i.e., biovolume concentration, size distribution, cell density, and column-integrated biovolume) of cyanoHABs in water bodies by using the laser scattering and transmissometry (LISST) instrument. The accuracy of measurements of the biovolume and colony size of algae was evaluated and exceeded 95% when the water bloom was dominated by cyanobacteria. Furthermore, the cell density of cyanobacteria was well estimated based on total biovolume and mean cell volume measured by the instrument. Therefore, this methodology has the potential to be used for broader applications, not only to monitor the spatial and temporal distribution of algal biovolume concentration but also monitor the vertical distribution of cell density, biomass and their relationship with size distribution patterns. This provides new technical means for the monitoring and analysis of algae migration and early warning of the formation of cyanoHABs in lakes and reservoirs.

中文翻译：

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使用 LISST-HAB 评估蓝藻水华的原位监测和垂直迁移


蓝藻有害藻华 (cyanoHAB) 在全球水生生态系统中变得越来越普遍。然而，其分布的不均匀性使得利用传统的监测方法难以准确估计藻类总生物量并预测表面cyanoHABs的发生。尽管各种光学仪器和遥感方法已被用来监测水面（即水华面积、叶绿素）的cyanoHABs动态，但目前还没有有效的方法来监测整个过程中藻类细胞密度和综合生物量的动态变化。水柱。在本研究中，我们提出了一种使用激光散射和透射测量（LISST）仪器同时测量水体中cyanoHABs的多个指标（即生物体积浓度、尺寸分布、细胞密度和柱积分生物体积）的定量方案。当水华以蓝藻为主时，对藻类生物体积和菌落大小测量的准确度进行了评估，结果超过95%。此外，根据仪器测量的总生物体积和平均细胞体积，可以很好地估计蓝细菌的细胞密度。因此，该方法有可能得到更广泛的应用，不仅可以监测藻类生物体积浓度的空间和时间分布，还可以监测细胞密度、生物量的垂直分布及其与尺寸分布模式的关系。这为湖泊、水库藻类迁移监测分析和氰基HABs形成预警提供了新的技术手段。