The Centre for Environment, Fisheries and Aquaculture Science (Cefas), The Nothe, Barrack Road, Weymouth, Dorset DT4 8UB, UK.
Centre for Ecology, Environment and Sustainability, Faculty of Science & Technology, Bournemouth University, Fern Barrow, Poole, Dorset BH12 5BB, UK.
Toxins (Basel). 2020 Aug 5;12(8):503. doi: 10.3390/toxins12080503.
Freshwater cyanobacteria blooms represent a risk to ecological and human health through induction of anoxia and release of potent toxins; both conditions require water management to mitigate risks. Many cyanobacteria taxa may produce microcystins, a group of toxic cyclic heptapeptides. Understanding the relationships between the abiotic drivers of microcystins and their occurrence would assist in the implementation of targeted, cost-effective solutions to maintain safe drinking and recreational waters. Cyanobacteria and microcystins were measured by flow cytometry and liquid chromatography coupled to tandem mass spectrometry in two interconnected reservoirs varying in age and management regimes, in southern Britain over a 12-month period. Microcystins were detected in both reservoirs, with significantly higher concentrations in the southern lake (maximum concentration >7 µg L). Elevated microcystin concentrations were not positively correlated with numbers of cyanobacterial cells, but multiple linear regression analysis suggested temperature and dissolved oxygen explained a significant amount of the variability in microcystin across both reservoirs. The presence of a managed fishery in one lake was associated with decreased microcystin levels, suggestive of top down control on cyanobacterial populations. This study supports the need to develop inclusive, multifactor holistic water management strategies to control cyanobacterial risks in freshwater bodies.
淡水蓝藻水华通过诱导缺氧和释放强效毒素对生态和人类健康构成威胁；这两种情况都需要进行水管理以减轻风险。许多蓝藻分类群可能产生微囊藻毒素，这是一组有毒的环状七肽。了解微囊藻毒素的非生物驱动因素及其存在之间的关系，将有助于实施有针对性的、具有成本效益的解决方案，以维持安全的饮用水和娱乐用水。在英国南部，对两个相互连接的水库进行了为期 12 个月的研究，这些水库在年龄和管理方式上存在差异，通过流式细胞术和液相色谱串联质谱法测量了蓝藻和微囊藻毒素。在两个水库中均检测到了微囊藻毒素，南部湖泊中的浓度明显更高（最高浓度> 7 µg L）。微囊藻毒素浓度的升高与蓝藻细胞数量没有正相关关系，但多元线性回归分析表明，温度和溶解氧解释了两个水库中微囊藻毒素变化的很大一部分。一个湖泊中存在管理渔业与微囊藻毒素水平降低有关，表明对蓝藻种群存在自上而下的控制。本研究支持需要制定包容性的、多因素的综合水管理策略，以控制淡水体中的蓝藻风险。
