El Nio/La Nia影响下北部湾海域浮游桡足类种类组成与多样性

Species composition and diversity of planktonic Copepods in Beibu Gulf during El Nio/La Nia

以1998年1月至1999年5月对北部湾海域进行的4个航次生态环境综合调查的资料为基础,分析El Nio/La Nia期间北部湾四季浮游桡足类种类组成与多样性,并对其与气候及海洋水文的关系进行初步探讨。结果显示,调查期间共出现浮游桡足类122种,其中32种周年出现,以春(82种)、夏(84种)较多,秋(52种)、冬(67种)较少;四季共出现优势桡足类13种,以广温广盐类型占主导,除微刺哲水蚤(Canthocalanus pauper)外,其余12种为季节性优势种;冬、夏两季受El Nio影响较大,优势种以中型桡足类为主;秋、春季大型桡足类优势地位较高,受La Nia影响明显;北部湾浮游桡足类多样性较高。分析表明,夏季北部湾水温和盐度对浮游桡足类群落多样性有一定影响,但在其他季节,这种影响不明显。

In base of the data of 4 comprehensive investigations on the ecological environment in Beibu Gulf during 1998. 1 - 1999. 5, we analyzed the seasonal species composition and diversity of planktonic Copepods during El Nino/La Nina, exploring the relation between them and marine hydrology. The results reveal that 122 species of Copepod are identified, among which 32 species occurred yearly. The species of Copepod are found relatively more in spring （ 82 ） and summer （ 84 ） , while less in autumn （ 52 ） and winter （67）. Among the 13 dominant species in 4 seasons which are mostly eurythermal and euryhaline, 12 species are seasonal species except Canthocalanus pauper. The meso-copepods, the dominant species in winter and summer, are affected by El Nino. The macro-copepods, which take relatively high proportion in autumn and spring, are influenced by La Nina. The Copepods in the area was dominated by wide-temperature and wide-salt species. The diversity of the planktonic Copepods in Beibu Gulf is relatively high. Water temperature and salinity may affect the community diversity of Copepods in summer, but the impact is not obvious in the other 3 seasons.