香溪河库湾春季水华纵向分布对水层结构的响应

为研究三峡水库支流库湾春季水华暴发空间差异及成因,本研究于2010年4月18日对三峡水库干流和香溪河库湾的水动力、营养盐、浮游植物等因子进行了现场监测.结果显示：三峡水库支流春季水华浮游植物生物量及群落结构空间差异较大,库湾中上游暴发了严重的硅藻水华,而下游及三峡水库干流没有水华;库湾中复杂的分层异重流对水温结构产生显著影响,使其呈独特的垂向分层;水温分层纵向差异导致的光混比（Zeu/Zmix）纵向分布差异是引起水华情势和浮游植物群落结构纵向差异的主要原因.研究结果将为三峡水库支流水华机理和防控措施研究提供支撑.

Response of Longitudinal Pattern of Spring Algal Blooms in Xiangxi Bay to Water Stratification

Field monitoring was conducted on April 18,2010 to investigate the spatial difference and its contributor of the spring algal blooms in the Three Gorges Reservoir and Xiangxi Bay.Field data of flow velocity,nutrients,phytoplankton biomass and structure,etc.were collected.The results show significant spatial difference in both phytoplankton biomass and structure in Xiangxi Bay.There were serious Diatom blooms at the middle and upper reaches of the bay while no blooms were found both at the lower reach and in the Three Gorges Reservoir.Special temperature structures were observed due to the influence of complex stratified density currents on thermal stratification.Spatial difference in thermal stratification is a main contributor to the longitudinal difference in Zeu/Zmix which causes significant spatial difference in spring algal blooms.The results will be of important references for investigation of mechanisms and management strategy of phytoplankton blooms in tributary bays of the Three Gorges Reservoir.