大亚湾春季小型底栖动物初步研究

Preliminary study on meiofauna in Daya Bay of South China Sea in spring

2010年4月对大亚湾海域的小型底栖动物丰度和生物及其它生物指标进行了研究。结果表明,小型底栖动物的平均丰度和生物量分别为(158.96±57.22)/cm2和(94.31±33.40)μg/cm2干质量,生产量为(848.76±300.61)μg/(cm2.a)。在分选的16个主要类群中,海洋线虫在丰度(97.64%)和生物量(65.83%)上均为绝对优势类群,桡足类(0.91%)在丰度上居其次,而多毛类(14.32%)在生物量上为第二优势类群。在垂直分布上,约49.82%的小型底栖动物分布在0～2cm层中;各类群中,桡足类的表层分布更为显著,线虫、桡足类以及多毛类位于0～2 cm表层的比例分别为49.55%、75.19%和44.71%。Pearson显著相关分析表明,小型底栖动物的丰度与生物量与环境因子均无显著相关关系,而通过单因素方差分析得知,各站位间的丰度与生物量差异均极显著(P<0.001)。通过对香浓威纳、Pielou均匀度等生物指数的计算以及N/C比值的统计均可总结出,位于澳头养殖区的站位群落的多样性较差,稳定度较低,因此得出生物指数和N/C值可作为生态评估的参考指标。

The abundance, biomass and some biotic indices of meiofauna in Daya Bay were investigated, based on samplings obtained from 9 stations in Apr. 2010 first time. The average abundance and biomass of total meiofauna amounted to （ 158.96±57.22）/cm2 and （94.31±33.40 ）μg/cm2 as dry weight, respectively, and the production reached （ 848.76±300.61 ）μg/（ cm2.a）. Among the 16 main meiofaunal groups sorted, free-living Nematoda dominated 97.64% on abundance and 65.83% on biomass, followed by Copepoda （0.91%） on abundance and Polychaeta （ 14.32% ） on biomass, respectively. In vertical distribution of the average abun- dance in top 0-10cm sediments, 49.82% of meiofauna was found in 0-2cm layer, Copepoda preferred to surfer layer and 75.19 per- cent was counted in 0-2cm layer, where 49.55% and 44.71% of Nematoda and Polychaeta were found respectively. There was no significant correlation between environmental parameters and abundance, biomass, and the abundance and biomass in the stations were different significantly.