贵州山区新建水库浮游植物群落结构特征

CHARACTERISTICS OF PHYTOPLANKTON COMMUNITY STRUCTURE IN NEWLY-BUILT RESERVOIRS IN MOUNTAINOUS AREA GUIZHOU PROVINCE

对贵州山区新建水库的浮游植物群落结构特征进行研究,有利于了解同类水库的浮游植物群落演替趋势,还可以评估水华发生的潜在风险,为管理部门提供参考。贵州省六盘水市的观音岩水库和万营水库,分别为2018年和2017年建成蓄水的新建水库,文章以实地调查为基础对两座水库的浮游植物群落结构特征及其与环境因子关系进行了研究。2018年11月至2019年10月间的季度调查显示,两座水库分别检出32种和28种浮游植物,优势种均以硅藻和绿藻为主,藻类平均密度分别为3.46×10^(6)和4.79×10^(6)cells/L。RDA分析结果显示,观音岩水库和万营水库浮游植物群落的主要驱动因子相同,均为水温(WT)、总磷(TP)和水体透明度(SD)。总体来说,新建水库在运行初期出现藻类暴发的风险较低,在后续管理中,应着重关注浮游植物密度受温度、外源营养及季节变化的影响。

Phytoplankton,as an important primary producer in aquatic ecosystem,is very sensitive to the changes of water nutrient status and environment.At the initial stage of operation of the new reservoir,the changes of hydrological situation may improve the interception ability of the water body to exogenous pollutants,which easily leads to abnormal phytoplankton reproduction and even blooms.Therefore,the study on the characteristics of phytoplankton community during this period is helpful to understand the succession trend of phytoplankton community in the reservoir and provide reference for the management.Guanyinyan Reservoir and Wanying Reservoir in Liupanshui City,Guizhou Province,were newly built in 2018 and 2017,respectively.Based on field investigation,this paper studied the phytoplankton community structure and its relationship with environmental factors in the two reservoirs.A quarterly survey was conducted on both reservoirs,and the results showed that diatoms and green algae dominated the phytoplankton in both reservoirs.A total of 32 species of phytoplankton were detected in Guanyinyan Reservoir,among which diatoms and chlorophyta accounted for 31.3%and 28.1%,respectively.The average annual density of phytoplankton was 3.46×10^(6)cells/L.The total species of phytoplankton was 28 in Wanying Reservoir,diatoms and chlorophyta accounted for 35.7%and 39.3%,respectively.The average annual density of phytoplankton was 4.79×10^(6)cells/L.According to the results of redundancy analysis(RDA),water temperature,total phosphorus and transparency were the main environmental factors affecting the changes of phytoplankton communities in the two reservoirs.In general,the newly built reservoirs in this study have a low risk of algal eruption in the early stage of operation.In subsequent management,attention should be paid to the influence of temperature,exogenous nutrition and seasonal changes on phytoplankton density.