夏季长江口及邻近海域沙海蜇数量分布和生长特征  

On the distribution and growth characteristics of Nemopilema nomurai in the Yangtze Estuary and adjacent areas in summer

作　　者：李建生[1] 凌建忠[1] 程家骅[1] 

机构地区：[1]农业部东海与远洋渔业资源开发利用重点实验室,中国水产科学研究院东海水产研究所,上海200090

出　　处：《海洋渔业》2017年第1期1-8,共8页Marine Fisheries

基　　金：公益性行业(农业)科研专项经费项目(201303047)

摘　　要：利用2013年和2014年的6~7月共6个航次在长江口近海对沙海蜇(Nemopilema nomurai)开展的定点调查和生物学测定数据,对该海域沙海蜇的数量分布和生长特征进行了研究。结果表明:春末夏初,沙海蜇幼体首先出现在长江冲淡水控制势力较弱的江苏省中南部近岸和长江口北部外海水域;随着水温回升,逐渐向长江冲淡水控制势力较强的海域和黄海冷水团控制的南黄海中央深水海域扩散,吕四近岸的出现率呈现降低的趋势,而外海出现率持续保持在高水平;7月下旬,随着沙海蜇伞径达到高峰值,在长江口及邻近海域呈现全面暴发的趋势。根据生长速度和出现率,把沙海蜇的生长分为3个阶段:发生初期,时间为6月上旬,出现率较低,个体较小;快速生长期,时间为6月中旬至7月上旬,出现率逐渐升高,生长速度前期较快,后期略有降低;暴发期,时间为7月中旬至7月下旬,出现率和伞径均达到最大值,生长速度呈现持续降低趋势。监测夏季长江口近海沙海蜇的数量分布和生长特征,对于预测当年伏季休渔后东黄海的沙海蜇暴发和对渔业生产预警具有重要的意义。In this paper, the distribution and growth characteristics of N. nomurai were studied based on the data of fixed station investigation and biological measurement of 6 cruises from June to July in 2013 and 2014 in the Yangtze Estuary. The results showed that N. nomurai larvae first appeared in the central and southern coast of Jiangsu province and northern areas of the Yangtze Estuary, where the control force of the Yangtze River diluted water was weak during late spring and early summer. With the increasing water temperature, N. nomurai gradually spreaded to the area where Yangtze River diluted water had more control or to the deep waters in the south central Yellow Sea controlled by the Yellow Sea cold water mass. The occurrence rate of N. nomurai showed a decreasing trend in Lvsi nearshore, while it was maintained at a high level off the coast. In late July, N. nomurai presented a comprehensive outbreak in the Yangtze Estuary and its adjacent waters as the bell diameter reached its peak. According to the growth rate and occurrence rate, the growth period of N. nomurai can be divided into three stages. The first stage was in early June called early occurrence, the occurrence rate was low and the individual was small at this stage. The next period was rapid growth period from mid-June to early July, the occurrence rate increased gradually, and the growth speed was rapid at the initial stage, and then slightly decreased. The last period was outbreak period from mid-July to late July, occurrence rate and bell diameter both reached the maximum, but the growth rate continued to show a decreasing trend. Monitoring the distribution and growth characteristics of N. nomurai in the Yangtze Estuary and adjacent waters in summer is significant in predicting the N. nomurai outbreaks and making early warning for fishery production after summer fishing moratorium.

关 键 词：夏季 长江口 沙海蜇 数量分布 生长 

分 类 号：S931[农业科学—渔业资源]