杭州湾洋山工程群对邻近水域浮游动物数量分布的影响

采用2001年5月、8月以及2003-2007年5月和8月杭州湾附近水域(30°32'-30°50'N、121°53'-122°17'E)2个季节12个航次的海洋调查资料,对浮游动物生物量平面分布和年际变化、优势种对总丰度的回归贡献,及其与洋山工程群施工建设的关系进行了研究.结果表明:监测水域6年间的5月和8月总生物量年均值分别为207.41 mg/m3和234.16 mg/m3.2007年为两季最高值,2003年和2004年分别为两季最低值.6年调查水域5月和8月的共同优势种为真刺唇角水蚤(Labidocera euchaeta).5月主要优势种有虫肢歪水蚤(Tortanus vermiculus)和中华哲水蚤(Calanus sinicus),8月为太平洋纺锤水蚤(Acartia pacifica)和背针胸刺水蚤(Centropages dorsispinatus).主要优势种对总丰度的贡献较大,尤其是5月的中华哲水蚤和8月的太平洋纺锤水蚤.浮游动物总生物量变化趋势和优势种的年际更替与工程进展有着明显的关系.施工期总生物量明显下降,主要工程区域的生物量同时降低,且主要优势种对总丰度的贡献率也降低.施工结束后,调查水域总生物量开始逐步回升,区域生物量逐步恢复到工程前水平.本研究旨在及时了解和掌握工程建设对环境的影响过程,并为生态环境保护措施的制订和渔业资源可持续利用等提供基础资料.

Effects of Yangshan Project in Hangzhou Bay on distribution of zooplankton biomass in the adjacent waters

Based on the data from two seasonal oceanographic surveys in adjacent water of the Hangzhou Bay --in spring (May) andthe annual alteration and horizontal distribution of zooplankton biomass, as well as the contribution of dominant species to total abundance were studied. Moreover, the relationship between the zooplankton and the engineering construction was also discussed. The results showed that the average of biomasses in May and August of 2001 and 2003 respectively. The biomass was the highest in May and August of Labidocera euchaeta the dominant species of the two seasons in the six years. In May Centropages dorsispinatus were the dominant ones in August. was the predominant one in August. These two species greatly contributed to the total abundance. In addition, the trend of zooplankton biomass and the annual succession of the dominant species were closely related with the progress of Yangshan project. The biomass decreased to the lowest point during the construction period and in the area where the major project located the zooplanktonic biomass was particularly low. Moreover, the contribution of the major dominant species to the total abundance was also low comparing with other periods. However, after the completion of the construction, the biomass of investigated water began to rise and the region biomass gradually recovered to the level before the construction of the project.