State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, People's Republic of China.
Environ Sci Pollut Res Int. 2015 Aug;22(16):12737-46. doi: 10.1007/s11356-015-4535-2. Epub 2015 Apr 28.
Wind waves are responsible for some of the spatio-temporal gradients observed in the biotic and abiotic variables in large shallow lakes. However, their effects on the phytoplankton community composition are still largely unexplored especially in freshwater systems such as lakes. In this paper, using field observations and mesocosm bioassay experiments, we investigated the impact of turbulence generated by wind waves on the phytoplankton community composition (especially on harmful cyanobacteria) in Lake Taihu, a large, shallow eutrophic lake in China. The composition of the phytoplankton community varied with the intensity of wind waves in the different areas of the lake. During summer, when wind waves were strong in the central lake, diatoms and green algae seemed to dominate while harmful cyanobacteria dominated in the weakly influenced Meiliang Bay. Turbulence bioassays also showed that diatoms and green algae were favoured by turbulent mixing. The critical time for the shift of the phytoplankton community composition was approximately 10 days under turbulent conditions. However, short-term (6 days) turbulence is rather beneficial for the dominance of cyanobacteria. This study suggests that the duration of wind events and their associated hydrodynamics are key factors to understanding the temporal and spatial changes of phytoplankton communities.
风浪是大浅湖生物和非生物变量中一些时空梯度的成因。然而，它们对浮游植物群落组成的影响在很大程度上仍未得到探索，特别是在淡水系统如湖泊中。在本文中，我们使用现场观测和中观生物测定实验，研究了风浪产生的湍流对中国大、浅、富营养化太湖浮游植物群落组成（特别是有害蓝藻）的影响。浮游植物群落的组成随湖内不同区域风浪强度的不同而变化。夏季，当中心湖区风浪较强时，硅藻和绿藻似乎占主导地位，而在受风浪影响较弱的梅梁湾，有害蓝藻则占主导地位。湍流生物测定也表明，硅藻和绿藻受到湍流混合的青睐。在湍流条件下，浮游植物群落组成发生转变的临界时间约为 10 天。然而，短期（6 天）的湍流对蓝藻的优势更为有利。本研究表明，风浪事件的持续时间及其相关水动力是理解浮游植物群落时空变化的关键因素。
