Wang Ji-Yi, Huo Di, Guo Chao-Xuan, Zhu Guang-Wei, Gong Zhi-Jun, Fan Ya-Wen, Wang Jian-Jun
College of Life Science and Technology, Harbin Normal University, Harbin 150025, China.
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
Huan Jing Ke Xue. 2022 Jul 8;43(7):3575-3586. doi: 10.13227/j.hjkx.202110117.
Clear vertical variations in phytoplankton community structure are usually observed in deep-water lakes and reservoirs, which is one of the key components of water quality and ecosystem functioning. However, the vertical patterns and ecological drivers of phytoplankton communities in deep-water lakes and reservoirs are still understudied. In this study, we took Qiandao Lake, a deep-water reservoir, as an example to reveal the vertical distribution characteristics of phytoplankton communities and its influencing factors by investigating phytoplankton community structure and the associated water quality index at 12 sites across the whole lake in two seasons (spring and autumn). The results showed that the phytoplankton abundance and chlorophyll were highest in the surface layer in autumn and then decreased toward deep water, whereas in spring, the maximum value occurred in the subsurface layer (2-5 m), and the dominant phytoplankton species showed obvious vertical stratification characteristics. Specifically, in spring, and dominated the surface and subsurface layers, dominated in the middle layer, and the abundance of at the bottom layer was significantly higher than that of the other algae genera. The dominant genera in autumn were and . In the subsurface and middle layers, and occupied the dominant position, and became the only dominant genus. In the bottom layer, was the only dominant genus. The key environmental indicators of the water also had obvious vertical changes. The contents of N and P nutrients had a negative correlation with the water depth in spring, whereas the reverse trend was observed in autumn. The correlation analysis showed that the vertical variation in phytoplankton abundance in spring was significantly positively correlated with phosphate concentration, whereas the vertical distribution of phytoplankton abundance in autumn was significantly positively correlated with intensity of light, and the water temperature, NH-N, and total nitrogen were the main factors driving the vertical changes in the dominant genera of phytoplankton community in the two seasons. To summarize, environmental conditions such as water temperature, light, and nutrients had strong effects on the vertical distribution of phytoplankton. In the ecological investigation and quality assessment of deep-water lakes and reservoirs, the vertical distribution characteristics of the phytoplankton community structure and the influence of environmental conditions should be fully considered.
在深水湖泊和水库中，通常会观察到浮游植物群落结构存在明显的垂直变化，这是水质和生态系统功能的关键组成部分之一。然而，深水湖泊和水库中浮游植物群落的垂直模式和生态驱动因素仍未得到充分研究。在本研究中，我们以深水水库千岛湖为例，通过在两个季节（春季和秋季）对全湖12个站点的浮游植物群落结构和相关水质指标进行调查，揭示浮游植物群落的垂直分布特征及其影响因素。结果表明，秋季浮游植物丰度和叶绿素在表层最高，然后向深水层降低，而在春季，最大值出现在次表层（2-5米），优势浮游植物种类呈现明显的垂直分层特征。具体而言，春季， 和 在表层和次表层占主导地位， 在中层占主导地位，底层 的丰度显著高于其他藻类属。秋季的优势属是 和 。在次表层和中层， 和 占据主导地位， 成为唯一的优势属。在底层， 是唯一的优势属。水体的关键环境指标也有明显的垂直变化。春季氮和磷养分含量与水深呈负相关，而秋季则呈现相反趋势。相关性分析表明，春季浮游植物丰度的垂直变化与磷酸盐浓度显著正相关，而秋季浮游植物丰度的垂直分布与光照强度显著正相关，水温、氨氮和总氮是驱动两个季节浮游植物群落优势属垂直变化的主要因素。综上所述，水温、光照和养分等环境条件对浮游植物的垂直分布有强烈影响。在深水湖泊和水库的生态调查和质量评估中，应充分考虑浮游植物群落结构的垂直分布特征和环境条件的影响。
