洋河水库微囊藻空间分布特征及其影响因素分析

通过野外调查及现场风速实时监测,对2010年夏季我国河北洋河水库微囊藻的空间分布特征及其影响因素进行了研究.结果表明,在水平空间上,西洋河口(主要入湖河口)微囊藻细胞密度最高,库心、北库心、坝前西、东洋河口等位置次之,坝前东(取水口)处微囊藻细胞密度最低,整体呈由水库西北向东南方向降低的趋势.Pearson相关性检验表明,洋河水库微囊藻细胞密度与ρ(TP)显著相关(P<0.05),但与ρ(DTP)、ρ(TN)及ρ(NO3--N)相关性不显著(P>0.05).风场分析表明,洋河水库水华发生季节东南风风频明显大于西北风,说明洋河水库微囊藻水平空间分布主要受入湖河流氮、磷污染及风场分布共同影响.西洋河口和库心的微囊藻昼夜垂向分布特征表现为早晨主要集中在水体的表层(10 cm),中午主要分布在水体0～3.5 m的水层,而傍晚时则可能下沉至底层,昼夜变化规律明显,并且其垂向分布特征主要受藻细胞的光合作用和风浪的混匀作用共同影响. 

Spatial Distribution Characteristics of Microcystis and Influencing Factors in Yanghe Reservoir

The spatial distribution of Microcystis in the Yanghe Reservoir in Hebei Province,China,was investigated from June to September 2010,and the various influencing factors,such as phosphorus,nitrogen and wind,were studied.The results showed a decreasing trend of Microcystis cell density from the northwestern to the southeastern parts of the reservoir.Cell density in the estuary of the Xiyang River was the highest,while that in the front of the east dam was lowest.Statistical analysis showed that cell density was significantly correlated with ρ(TP)(P<0.05),but not with ρ(DTP),ρ(TN) or ρ(NO3——N)(P>0.05).Wind field analysis showed a higher frequency of southeastern wind than northwestern wind.These results suggested that the horizontal distribution of Microcystis was influenced by nutrient inflows and wind.The vertical distribution of cell density showed that most Microcystis was concentrated on the surface layer(10 cm) in the morning,scattered in the water at 0-3.5 m depth at noon,then sunk to the bottom in the evening.This implied that the vertical distribution of Microcystis was mainly determined by photosynthesis,and the wave forms were induced by wind.