巢湖和太湖春季微囊藻毒素动态差异及与环境因子的关系

为探究春季巢湖和太湖水体中胞内微囊藻毒素(IMCs)动态变化时空差异及其关键影响因子,于2019年3—5月对两湖不同湖区进行采样分析。结果表明:春季巢湖和太湖的IMCs呈现明显的时空分布特征,IMCs浓度逐月增加,在富营养化水平高的湖区明显高于富营养水平低的湖区;两湖IMCs的异构体均以IMC-LR为主,占比分别为65.10%和58.10%;3—5月两湖IMCs浓度差异明显,巢湖月均IMCs浓度(0.077、0.238、0.632 μg/L)明显高于太湖(0.021、0.031、0.166 μg/L),单位生物量IMCs及其异构体LR的毒性(IMCs/Chla和IMC-LR/Chla)也明显高于太湖。相关性分析表明,总氮(TN)、总磷(TP)浓度和TN/TP是影响IMCs浓度和单位生物量IMCs毒性的关键环境因子,同时产毒藻的丰度和产毒能力也可能是造成此差异的重要原因。

Dynamic differences of microcystins and their relationship with environmental factors in spring in Lake Chaohu and Lake Taihu

In order to explore the dynamic differences of intracellular microcystins (IMCs) and key influencing factors in spring for Lake Chaohu and Lake Taihu, samples were analyzed from different lake areas of this two lakes in March, April and May of 2019. The results indicated that IMCs showed obvious temporal and spatial distribution characteristics in Lake Chaohu and Lake Taihu during the sampling period, the concentration of IMCs increased month by month, and IMCs in the high eutrophication lake area was significantly higher than that in the low eutrophication lake area. IMC-LR was the main isomer of IMCs in the two lakes, accounting for 65.10% and 58.10%, respectively. IMCs concentration between the two lakes were significantly different, the average concentration of IMCs in Lake Chaohu (0.077, 0.238, 0.632 μg/L) was obviously higher than that in Lake Taihu (0.021, 0.031, 0.166 μg/L), and the toxicity of IMCs per unit biomass (IMCs/Chla and IMC-LR/Chla) was also significantly higher than that in Lake Taihu. The correlation analysis showed that TN, TP and TN/TP were the key environmental factors affecting the concentration of IMCs and the toxicity of IMCs per unit biomass, and the abundance and capacity of toxin-producing algae may be the important reasons for the difference.