紫霞湖浮游甲壳动物昼夜垂直迁移

2010年9月19～21日,对江苏南京紫霞湖(水深8.5m)浮游甲壳动物昼夜垂直迁移行为进行了调查,分析了影响昼夜垂直迁移的因素。结果表明,奥氏秀体溞(Diaphanosoma orghidani)、象鼻溞(Bosmina sp.)、颈沟基合溞(Bosminopsis deitersi)、台湾温剑水蚤(Thermocyclops taihokuensis)和中华原镖水蚤(Eodiapotomus sinensis)成体均表现出昼夜迁移现象,中华原镖水蚤幼体和无节幼体无明显昼夜迁移。紫霞湖的温度、溶解氧和叶绿素a浓度的垂直变化不是导致浮游甲壳动物昼夜垂直迁移的主导因子,光照强度和鱼类捕食可能是影响浮游甲壳动物昼夜垂直迁移的主要因素。

Diel Vertical Migration of Crustacean Zooplankton in Lake Zixia and Analysis of Its Impacted Factors

Diel vertical migration (DVM) of the crustacean zooplankton was investigated from September 19 to 21, 2010 in Lake Zixia, Nanjing. The depth of the site for DVM investigation was 8.5 m. The physiochemical factors, chlorophyll a and fish composition were measured for analyzing the possible factors impacting the DVM. The results showed that Diaphanosona orghidani, Bosmina sp., Bosminopsis deitersi, Thermocyclops taihokuensis and adult Eodiapotomus sinensis had evident diel vertical migration. Nauplii and juveniles of Eodiapotomus sinensis showed no diel vertical migration. The analysis indicated that temperature, dissolved oxygen and cholorophyll a were not the main factors for DVM. Light intensity and fish predation were important factors affecting the diel vertical migration of crustacean zooplankton. DVM of crustacean zooplankton were also related to species and sizes of zooplankton.