烟台海洋倾倒区生物群落结构现状及动态变化分析

Analysis of the features and dynamic changes of biological community structure in the Yantai marine dumping site

利用烟台海洋倾倒区2008年的监测结果和相关历史资料,分别对倾倒区的生物群落结构现状及动态变化过程进行研究。倾倒区内目前有浮游植物18种,浮游动物23种,底栖生物17种。浮游植物以硅藻门的新月菱形藻(Nitzschia closterium W.Smith)占有绝对优势,浮游动物的优势种为中华哲水蚤(Calanus sinicus Brodsky)和强壮箭虫(Sagitta crassa Tokioka),底栖生物的组成以环节动物最多,优势种不明显。综合指数分析表明倾倒区海域的生物群落结构相对稳定。然而,多年的疏浚物倾倒使该区的生物群落发生了变化。与倾倒初期相比,浮游植物的种类数量减少,物种多样性总体上呈现下降趋势;浮游动物的种类数量和密度在2006年的调查中出现最低值,群落结构趋向单调,至2008年这一趋势有所缓和;底栖生物的种类数量和密度较倾倒初期也有明显的下降,多样性指数的降低和优势度的增大也预示群落结构稳定性的下降。

Based on the observed data of each monitoring from 1991 to 2008 in Yantai marine dumping site, the current features and dynamic changes of biological community structure were studied. In the survey of 2008, a total of 18 taxon of phytoplankton, 23 taxon of zooplankton and 17 taxon of benthos are identified. The dominant phytoplankton species is Nitzschia closterium. Calanus sinicus and Sagitta crassa are the dominant species of zooplankton. The benthos is mainly composed by annelida, but the dominant species is not evident. The diversity analysis shows that the biological community structures are relatively normal. However, long time disposal of dredged materials have changed the biological communities in Yantai dumping site. The variety and diversity of phytoplankton decrease compared with priory period of disposal. The variety and density of zooplankton have a minimum in the survey of 2006 and the community structure tends to be simple until 2008. To benthos, the variety and density decrease apparently in comparison with priory period of dredge materials disposal. The decrease of Shannon-Weaver diversity index and increase of Dominance index indicate the decline of the stability of benthos community.