莱州湾大型砂壳纤毛虫丰度的水平分布

The Horizontal Distribution of Dominant Large Tintinnid (Ciliophora, Tintinnida) in Laizhou Bay

中文关键词: 砂壳纤毛虫  优势种  水平分布  莱州湾

英文关键词: Tintinnid  Dominant species  Horizontal distribution  Laizhou Bay

中文摘要:

      根据2011年511月及2012年34月在莱州湾进行的每月1次共9个航次的调查资料，通过解剖镜下镜检浮游生物网拖网样品，分析莱州湾311月大型砂壳纤毛虫丰度的水平分布。结果显示，砂壳纤毛虫总丰度的水平分布在不同时间呈现不同的特点：3–5月砂壳纤毛虫总丰度在湾底较高，向湾口递减；611月砂壳纤毛虫总丰度在湾中及湾口较高，湾底近岸海区较低。各月砂壳纤毛虫丰度较大的区域温度、盐度比较相似，表明砂壳纤毛虫可能有一定的适温性和适盐性。其中，6月砂壳纤毛虫丰度的分布与同期调查的鱼卵和仔稚鱼的分布较一致，表明砂壳纤毛虫可能是仔稚鱼的开口饵料，对鱼类仔稚鱼的成活和发育有帮助。311月砂壳纤毛虫种丰富度的变化范围是520种，有17个种在不同月份成为优势种。优势种种类数最多的是7、8月(10种)，4月最少(2种)。各航次中不同优势种的最大丰度为489×103个/m3 (运动类铃虫Codonellopsis mobilis，5月)；较小的丰度仅为4×103个/m3 (半旋拟铃虫Tintinnopsis hemispiralis，11月)。主要优势种(连续3个月或3个月以上为优势种的种类)有运动类铃虫(C. mobilis)、白领细壳虫(Stenosemella nivalis)、根状拟铃虫(Tintinnopsis radix)、妥肯丁拟铃虫(T. tocantinensis)和半旋拟铃虫(T. hemispiralis)。8月在黄河入海口附近的3个站位发现河口拟铃虫(Tintinnopsis estuariensis)，这是在长江口海域发现的砂壳纤毛虫新种。

英文摘要:

      Tintinnid is one of the major species of microzooplankton, and it has been suggested to be the food source of the first-feeding fish larvae in the marine environment. We studied a large number of large tintinnid in Laizhou Bay during 9 cruises from May to November in 2011 and from March to April in 2012. The study on the horizontal distribution of large tintinnids in Laizhou Bay from March to November enriched the basic data for the development and utilization of fish resources in Laizhou Bay. The total abundance of tintinnid was higher in the inner bay than in the outer bay from March to May. Most tintinnids concentrated in the inner or outer bay from June to November. The temperature and salinity related to the largest tintinnid abundance remained stable in different months, which suggested that tintinnid might be adapted to different temperatures and salinities within a certain range. The distribution of tintinnid in June was consistent with the distribution of fish eggs and larvae, which indicated that tintinnid was the seasonally advantageous for the first-feeding fish larvae as a food source. The richness of tintinnid species ranged from 5 to 20. A total of 17 species were identified as dominant species in the 9 different months. The maximum abundance of Codonellopsis mobilis, a dominant species, was 489×103 ind/m3 in May, but the maximum abundance of another dominant species, Tintinnopsis hemispiralis, was only 4×103 ind/m3 in November. The richness of the dominant species ranged from 2 (in April) to 10 (in July and August). In July and August, the abundances of dominant species were small, and the tintinnids were distributed. In other months, a large proportion of dominant species abundance concentrated in the inner or outer bay, and it dramatically affected the total abundance. C. mobilis, Stenosemella nivalis, Tintinnopsis radix, Tintinnopsis tocantinensis, and T. hemispiralis were the major dominant species that had been dominant for at least 3 months consecutively. Tintinnopsis estuariensis was found in August which appeared nearby the Yellow River estuary, although the salinity was higher than the previous records. It was a newly recorded species.