福建东山湾浮游动物的种类组成与数量分布特点

Species Composition and Distribution of Zooplankton in Dongshan Bay

本文分析了2007年3月～11月于东山湾采集的浮游动物样品。结果表明,东山湾已鉴定的浮游动物有84种,其中水母类26种,桡足类37种,其它还有多毛类、介形类、枝角类、端足类和被囊类等以及阶段性浮游幼虫和少量的仔稚鱼,分为5个生态类群,以沿岸暖水类群和半咸水类群为主。浮游动物的种类数、总个体数和生物量的平面分布趋势大体相似,即湾口大于湾内,东部大于西部。总个体数与生物量的周年变化趋势非常相似,高峰出现在高温季节的8月,低谷出现在5月。调查期间东山湾浮游动物较为丰富,年均总个体数达982.3ind/m3,生物量达163.2mg/m3。与历史资料对比表明,东山湾的浮游动物物种多样性趋向减少,表现出优势种品种简单化而数量密集的倾向,这可能与湾内污染增加及环境变化有关,而生物量的增加可能与全球气候变暖及营养盐的增加有关。另外还对浮游动物的分布与环境因子的关系进行了分析。

Based on the samples collected from the survey in Dongshan Bay during the period of March 2007 and November 2007, the analysis showed that there were 84 species in the surveyed areas. The zooplankton can be divided into 5 eeotypes, among them, estuary low salinity groups and coastal warm - temperate groups were dominated. The biomass in terms of dry weight, species diversity and total individual amount of zooplankton were higher in the samples collected from outside of the bay than those within the bay. Similarly, samples of the eastern boundaries of the bay had higher biomass, diversity, and total individual amount than those of the western boundaries. Monthly average of total individual amount and biomass of dry weight were changed in the same hale. The yearly average total individual amount was 982. 3ind/m^3 and the biomass of dry weight was 163. 2mg/m^3. Contrasted to the historical data, it showed that the diversity of species was reduced, and the dominant species were centralized. It could be effect of the environmental pollution in the bay. The increase of dry weight was related to global warming and the increase of nutrient salts in sea water. The distribution of zooplankton and its relations with environmental factors were also analyzed.