Harmful algal blooms (HABs) in freshwater produce toxins that pose a threat to public health and aquatic ecosystems. Although algal communities have been studied globally to understand the characteristics of HABs, the occurrence of toxic cyanobacteria in freshwater ecosystems is rarely understood. Unlike abiotic factors, the effects of biotic factors (e.g., interaction, dominance, and variability) on the occurrence of toxic cyanobacteria were overlooked due to the intricate interaction of microorganisms under different environmental conditions. To address this problem, a comprehensive ecological concept stability, which encompasses variations in species or communities due to changing biological interactions or environmental fluctuations, was applied in this study. The algal communities in six river-connected lakes in the North Han River, South Korea, were classified into high and low stability groups. The algal species belonging to diatoms and green algae groups played a major role in the interaction within the algal community in highly stable lakes, but the frequency of Microcystis led the interaction within the algal community at the center of the network in low-stability lakes. These results indicate that the interaction within the cluster is easily changed by Microcystis, where the abundance explosively increases in lakes with low algal community stability. Water quality is more strongly associated with the occurrence of toxic cyanobacteria (Microcystis and Dolichospermum). In low-stability lakes, more diverse water quality indicators are correlated with the development of toxic algae than in high-stability lakes. This paper is the first report on the importance of algal community stability in freshwater in the occurrence of toxic cyanobacteria and offers a new perspective on Microcystis monitoring and management.

淡水中的有害藻华 (HAB) 会产生毒素，对公共健康和水生生态系统构成威胁。尽管已经在全球范围内研究了藻类群落以了解 HAB 的特征，但很少了解淡水生态系统中有毒蓝藻的发生。与非生物因素不同，由于微生物在不同环境条件下的复杂相互作用，生物因素（例如，相互作用、优势和变异性）对有毒蓝藻发生的影响被忽视了。为了解决这个问题，本研究应用了综合生态概念稳定性，其中包括由于生物相互作用或环境波动的变化而导致的物种或群落变化。汉江北部6个接江湖泊中的藻类群落，韩国，被分为高稳定性组和低稳定性组。属于硅藻和绿藻群的藻类在高度稳定的湖泊中藻类群落内的相互作用中起主要作用，但微囊藻在低稳定性湖泊网络中心领导藻类群落内的相互作用。这些结果表明集群内的相互作用很容易被微囊藻改变，在藻类群落稳定性较低的湖泊中，微囊藻的丰度呈爆炸性增加。水质更强烈地与有毒蓝藻（的发生相关联的微囊和Dolichospermum）。在低稳定性湖泊中，与高稳定性湖泊相比，更多样化的水质指标与有毒藻类的发展相关。这篇论文是第一篇关于淡水中藻类群落稳定性对有毒蓝藻发生的重要性的报告，并为微囊藻的研究提供了新的视角。 监测和管理。