|着生藻类一般生长位置相对稳定，其群落分布主要受环境因素的影响，同时，着生藻类还是重要的水环境指示生物.本研究对鄱阳湖丰水期5个典型湖区（主航道、西部湿地、南矶湿地、撮箕湖和东南湖汊）着生藻类的群落结构特征进行调查，包括生物量、优势种及生物多样性，分析影响着生藻类群落区域分布的环境因子，以期为鄱阳湖水环境保护和水资源合理利用提供基础资料.结果表明：鄱阳湖着生藻类群落以硅藻、绿藻和蓝藻为主；鄱阳湖着生藻类总生物量有着明显的区域差异：主航道区域的生物量相对最高，平均为419 mg/m2；其次是东南湖汊，平均为322 mg/m2；南矶湿地和西部湿地分别为172和52 mg/m2；而撮箕湖的总生物量相对最低，为9 mg/m2.主航道的着生藻类优势种群为绿藻和硅藻，西部湿地、南矶湿地、撮箕湖和东南湖汊4个区域的优势种群为硅藻.冗余分析结果显示鄱阳湖丰水期着生藻类群落分布与总磷、电导率、pH值、总氮、硝态氮和悬浮物等理化因子关系较为密切.鄱阳湖主航道与长江连通，水体流速高；西部湿地、南矶湿地、撮箕湖和东南湖汊为季节性连通湖泊，丰水季节与主湖区水体连为一体，枯水季节独立蓄水.5个湖区的区域差异是导致其着生藻类群落结构差异的重要原因之一.着生藻类的多样性指数分析表明鄱阳湖水体处于中度污染状态.
|关键词: 鄱阳湖 着生藻类群落 丰水期 空间分布
|Spatial distribution characteristics of periphytic algae community of Lake Poyang in the high water level phase
Qian Kuimei1, Liu Xia2, Chen Yuwei3
1.Jiangsu Key Laboratory of Industrial Pollution Control and Resource Reuse, Xuzhou University of Technology, Xuzhou 221018, P. R. China;2.Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China;3.Nanchang Institute of Technology, Nanchang 330099, P. R. China
|Periphytic algae usually attached stably on the substrate, and its community structure is mainly affected by environmental factors. Meanwhile, periphytic algae are important biological indicators of aquatic environment. In this study, we examined the community structure of periphytic algae in the high water level phase in 5 different areas of Lake Poyang (the main channel area, West wetland, Nanji wetland, Cuoji Lake, and Southeast Lake), including biomass, dominant species, and biodiversity. The relationship between environment and periphytic algae was analyzed. This study can provide basic data for aquatic environment protection and water resources use of Lake Poyang. The results show that Bacillariophyta, Chlorophyta, and cyanobacteria are dominant in the periphytic algae community of Lake Poyang. There are obvious spatial differences of periphytic algae biomass in Lake Poyang. The biomass of periphytic algae in the main channel is highest, averagely 419 mg/m2; followed by Southeast Lake, averagely 322 mg/m2. The average biomass of periphytic algae in the Nanji wetland and West wetland are 172 and 52 mg/m2, respectively. The biomass of periphytic algae in the main channel is lowest, averagely 9 mg/m2. The dominant populations of periphytic algae in the main channel are Bacillariophyta and Chlorophyta, while the dominant populations in the other four regions, i.e. West wetland, Nanji wetland, Cuoji Lake, and Southeast Lake, are Bacillariophyta. The redundancy analysis showed that the distribution of periphytic algae community in the high water level phase in Lake Poyang is closely related to physical and chemical factors such as total phosphorus, electrical conductivity, pH value, total nitrogen, nitrate nitrogen, and suspended solids. The main channel of Lake Poyang is connected to the Yangtze River with high water flow velocity. West wetland, Nanji wetland, Cuoji Lake, and Southeast Lake are seasonally connected with Lake Poyang. They are connected to the main body of Lake Poyang in the high water level phase and are separate regions in the low water level phase. The different regional characteristics of five regions are one of the important reasons for the spatial variations of periphytic algae community structure. The diversity index of periphytic algae indicated that the water body of Lake Poyang is in a moderately polluted state.
|Key words: Lake Poyang periphytic algae community high water level phase spatial distribution