鄱阳湖蓝藻分布及其影响因素分析

利用鄱阳湖的原位监测数据,分析鄱阳湖水华蓝藻的分布现状及其影响因素,探索鄱阳湖水华蓝藻的源头.研究结果表明,鄱阳湖浮游植物的优势种为硅藻,蓝藻为鄱阳湖的次级优势种,蓝藻在浮游植物总生物量的比例有逐年增加的趋势.水华蓝藻的主要优势种为鱼腥藻,其次为微囊藻和浮游蓝丝藻. 鄱阳湖蓝藻水华形成初期的基本规律为水华蓝藻在营养盐浓度相对较高且水流较缓的内湾及尾闾区生长分布,在夏秋季水位较高时在水流和风的作用下向主航道输移聚集. 结合鄱阳湖水文特点,主航道的水华蓝藻聚集有可能是上游四个湖区的蓝藻向下游漂移综合作用的结果.研究成果可为控制鄱阳蓝藻水华区域风险灾害提供基础数据.

Distribution and its influencing factors of bloom-forming cyanobacteria in Poyang Lake

The field monitoring data was used to analyze the distribution and its influencing factors of bloom-forming cyanobacteria and explore the source of bloom-forming cyanobacteria in Poyang Lake. It resulted that diatoms was dominant in Poyang Lake, cyanobacteria was sub-dominant, and there is a rising trend of the proportion of cyanobacteria in the composition of phytoplankton. The dominant species of cyanobacteria were Anabaena Sp., Microcystis Sp. and Planktonic Lansi. The basic law of the formation of cyanobacterial blooms at the initial stage was that cyanobacteria grow and distributed in the lentic regions with relatively high nutrient concentrations and slow flow, and then transported and gathered in the main channel under stress of flow and wind in summer and autumn in Poyang Lake. Combined with hydrologic characteristics, cyanobacteria aggregates floating in the surface of main channel in Poyang Lake was the combined effects of other four upstream regions. It can provide the basic data and information for the prevention and control of cyanobacteria blooms.