莱州湾海洋浮游和底栖生物多样性分析

Analysis of marine plankton and benthos diversity in the Laizhou Bay

利用莱州湾海域历年综合调查和生态监测资料,综合分析了莱州湾浮游植物、浮游动物、底栖生物等主要海洋生物类群的多样性状况及其长期变化特征。结果表明,莱州湾浮游植物种类繁多,不同航次调查物种数在几十至上百种不等,优势种周年变动和年际变化具有群落演替的特征,总细胞丰度在季节和年际间均呈指数变化,多样性指数H’（log2）平均值为2.64,秋季相对高于春季和夏季,且1959年显著高于20世纪80年代后的年份。莱州湾浮游动物种类以桡足类为主,单航次调查物种数相对浮游植物较少,优势种组成相对稳定,个体密度近几年有下降的趋势,多样性指数H’在1.74~2.52之间波动。莱州湾底栖生物种类众多,单航次调查大型底栖动物物种数一般就超百种,优势种以多毛类和双壳类为主,近几年呈现高丰度和低生物量的特点,多样性指数H’近几年监测结果有升高趋势,但相对20世纪80年代仍属低值。

Based on the data from historical field survey and recent ecological monitoring, biodiversity of the main ma- rine species and its long-term variations were studied in the Laizhou Bay. Phytoplankton, zooplankton, and benthos were analyzed respectively. The results showed that phytoplankton species in the Laizhou Bay was of a wide variety from tens to more than a hundred in different cruises. Both annual and inter-annual variations of the phytoplankton dominant species were characterized by community succession, and the total phytoplankton abundance varied exponen- tially. The diversity index H＇ （ log2 ） of phytoplankton community averaged 2.64. The mean H＇ in autumn was higher than that in spring and summer, while the mean H＇ in 1959 was much higher than that after 1980s. The main zoo- plankton group was eopepods, and the species number of zooplankton community was lower than that of phytoplankton. The composition of dominant zooplankton species was relatively stable, and the individual density had a decreasing trend in recent years. The diversity index H＇ of zooplankton community was at a range of 1.74 - 2.52. The benthic species in the Laizhou Bay was numerous, and the species number of only maerobenthos could reach more than a hun- dred in a single cruise. The dominant macrobenthic species were mainly polychaetes and bivalves. In recent years, the maerobenthos were characterized by high abundance and low biomass, and the diversity index H＇ had an increasing trend but still low relatively to that of 1980s.