贵州百花水库浮游藻类功能群时空分布特征及影响因子分析

为了探究百花水库浮游藻类功能群时空分布特征及其环境影响因子，于2012年11月（枯水期）、2013年4月（平水期）和2013年7月（丰水期）对浮游藻类群落结构与水环境理化指标进行采样分析.基于浮游藻类功能群、综合营养状态指数、Shannon-Wiener指数、RDA（冗余分析）等方法，分析浮游藻类功能群的群落组成和时空分布特征.结果表明:①共鉴定浮游藻类7门67属58种，其可划分为21个功能群.浮游藻类丰度从枯水期→平水期→丰水期递增，分别为131.99×104、592.27×104、53 140.81×104 L-1.②根据浮游藻类丰度，B功能群小环藻（Cyclotella sp.），J功能群栅藻（Scenedesmus sp.）、盘星藻（Pediastrum sp.）、空星藻（Coelastrum sp.），P功能群颗粒直链藻（Melosira granulate）、鼓藻（Penium sp.），S1功能群湖泊假鱼腥藻（Pseudanabaena limnetica）、湖丝藻（Limnothrix sp.）为优势功能群；浮游藻类功能群季节变化明显，其时空分布特征（枯水期→平水期→丰水期，下同）为P+B+J→J+P→S1.在垂直层面上，枯水期以硅藻组成的P、B功能群在各采样点底层藻类丰度达到最大，中层和底层丰度远高于表层，与P、B类群耐受低光的因素有关；平水期以绿藻组成的J功能群在各采样点15 m藻类丰度达到峰值，与J类群耐受低光的因素有关；丰水期以蓝藻组成的S1功能群在各水层表层藻类丰度达到最大，与S1适宜较高水温的因素有关.③RDA分析结果表明，WT（水温）是影响百花水库浮游藻类时空分布的主要环境因子.研究显示，根据浮游藻类绝对优势功能群（P、B、J、S1）以及不同季节生长策略（R/CR/CR→CR/R→R）可以判定百花水库处于中-富营养化状态. 

Spatial and Temporal Distribution Characteristics of Phytoplankton Functional Groups and Their Influencing Factors in Baihua Reservoir, Guizhou Province

In order to explore the spatial and temporal distribution of phytoplankton functional groups and the environmental factors affecting at Baihua Reservoir in Guizhou Province, the water samples were collected in November 2012 (dry period), April 2013 (level period) and July 2013 (flood period). The community composition and spatio-temporal distribution characteristics of phytoplankton functional groups were analyzed based on the phytoplankton functional groups, comprehensive nutritional status index, Shannon-Wiener index and redundancy analysis (RDA), the results showed that:a total of 67 species belonging to 58 genera and 7 phylum of planktonic algae were identified, which can be divided into 21 functional groups. The abundance of phytoplankton was increased from the dry period to level period to flood period, which were dry period (131.99×104 L-1), level period (592.27×104 L-1), flood period (53 140.81×104 L-1) respectively. According to the abundance of phytoplankton, B (Cyclotella sp.), J (Scenedesmus sp., Pediastrum sp.and Coelastrum sp.), P (Melosira granulate and Penium sp.) and S1 (Pseudanabaena limnetica and Limnothrix sp.) were dominant in the functional groups. The seasonal variation of phytoplankton functional groups was significant, and its spatial and temporal distribution characteristics were as follows:P+B+J in dry period, J+P in level period, and S1 in the flood period. At the vertical level, the dominant functional groups P and B in Baihua Reservoir, Guizhou Province during the dry period were the highest one in all samples, and the abundance of middle and bottom waters was much higher than that of the surface water, which was related to the low-light tolerance of P and B groups. The dominant functional group J consisting of Chlorophyta in the level period reached a peak at 15 m of each sampling point, which was related to the low-light tolerance of the J group. In the flood period, the functional group S1, which was composed of Cyanophyta, had the highest abundance of algae on the surface water layers, and it was suitable for higher water temperature. The results of RDA showed that water temperature (WT) was the main environmental factor, which affected the spatial and temporal distribution of phytoplankton in Baihua Reservoir. The results showed that in the light of the absolute dominant functional groups of planktonic algae (S1) and the growth strategies of different seasons (dry period growth strategy R/CR/CR→level period growth strategy for the CR/R→flood period growth strategy R), it revealed that the Baihua Reservoir in Guizhou Province was in the mesotrophic status.