云贵高原渔洞水库浮游植物群落结构及季节演替

2009年11月至2010年10月对云南省昭通市渔洞水库浮游植物群落结构及季节演替进行了周年调查。结果表明,常见浮游植物共7门、96种;其中,绿藻门52种,硅藻门22种,蓝藻门13种,甲藻门3种,隐藻门、金藻门和裸藻门各2种。浮游植物生物量的季节变化表现为春、冬季较低,夏、秋季较高,且在8月达到浮游植物生物量(以细胞数计)最高峰值1.19×107个/L,叶绿素a最高峰值可达28.6μg/L。渔洞水库全年以硅藻门的钝脆杆藻(Fragilaria capucina)和尖针杆藻(Synedra acus)为主要优势种;另外,3-5月甲藻门的角甲藻(Ceratium hirundinel-la)及金藻门的分歧锥囊藻(Dinobryon divergens)是显著的亚优势种。将周年调查结果进行RDA分析,可见影响浮游植物季节演替的主要因素是水温,水温变化与浮游植物生物量成极显著正相关关系(r=0.762,P<0.01);与浮游植物种类数成极显著负相关关系(r=-0.721,P<0.01),与浮游植物生物多样性成显著负相关关系(r=-0.638,P<0.05)。

Community Structure and Seasonal Succession of Phytoplankton in Yudong Reservoir of Yungui-plateau

The community structure and seasonal succession of phytoplankton were investigated every month from November 2009 to October 2010 in the Yudong Reservoir,Zhaotong City,Yunnan Province.A total of 96 phytoplanktonic algal species belonging to 7 phyla were identified,including 52 species of Chlorophyta,22 species of Bacillariophyta,13 species of Cyanophyta,3 species of Pyrrophyta,and 2 species each of Cryptophyta,Chrysophyta,and Euglenophyta.The biomass of phytoplankton in the reservoir was lower in winter and spring that in summer and autumn.The peak cell density of algae was 1.19×107cells/L in August and the peak chlorophyll-a concentration was 28.6 μg/L.The dominant species in the reservoir were Fragilaria capucina Desm.and Synedra acus Kütz.of the Bacillariophyta at all times of the year,in addition,Ceratium hirundinella(müll.) Schr.of Pyrrophyta and Dinobryon divergens Imh.of Chrysophyta were subdominant species from March to May.The relationship between seasonal succession of phytoplankton and environmental factors was analyzed by using redundancy analysis(RDA).The result showed that the most important factor was water temperature.Water temperature presented a significant positive correlation with biomass of phytoplankton in the reservoir(r=0.762,P<0.01),but a significant negative correlation with phytoplankton species(r=-0.721,P<0.01),and a negative correlation with diversity index(r=-0.638,P<0.05).