摘要: |
根据 2006 年 8 月、2007 年 1 月、5 月和 11 月 4 个季节在舟山渔场及邻近海域(29?30′N—32?00′N, 127?00′E 以西)开展海洋生态系统综合调查所获得的头足类资料, 用渔获率作为头足类分布的数量指标, 分析了该海域的头足类种类组成、数量分布以及季节变化趋势。结果表明, 该海域共鉴定头足类 25 种, 隶属于 3 目 8 科 9 属。以浅海种类为主, 渔获量以长蛸、短蛸较高, 分别占头足类总渔获量的 34.93%、30.06%, 另外, 神户枪乌贼、双喙耳乌贼等也占有一定比例。渔获量高峰期主要出现在夏季, 以长江口渔场和舟山渔场为较高, 春季以长江口渔场和江外渔场相对较高, 秋季头足类在舟山渔场的出现率高于长江口渔场, 但是平均渔获率以长江口渔场为最高。冬季调查海域的头足类数量不多, 分布较分散, 仅在长江口渔场的个别站位有出现。与以往的调查结果比较, 该海域头足类群落结构发生了很大的变化, 以往的优势种类——日本无针乌贼已严重衰退, 从优势种类更替为浅海小型种类。
|
关键词: 头足类, 种类组成, 数量分布, 舟山渔场及邻近海域 |
DOI:10.11693/hyhz201101019019 |
分类号: |
基金项目:国家自然科学基金项目, 30970464号; 浙江省科技厅资助项目, 2006C23051号; 国家海洋局项目, 908-01-ST-04号 |
附件 |
|
SPECIES COMPOSITION AND QUANTITATIVE DISTRIBUTION STUDY ON CEPHALOPOD IN THE ZHOUSHAN FISHING GROUND AND ADJACENT WATERS |
QIN Tao1, YU Cun-Gen1, CHEN Quan-Zhen2, NING Ping1,2, ZHENG Ji1
|
1.Marine Fishery College of Zhejiang Ocean University;2.Second Institute of Oceanography, State Oceanic Administration
|
Abstract: |
Based on four seasonal data of the comprehensive survey of marine ecosystem in August, 2006 and January, May, and November 2007, we used CPUE (catch per unit effort) as the index for quantitative distribution of cephalopod, and analyzed the changes of species composition, and quantitative distribution of cephalopod in 29?30′—32?00′N, west of 127?00′E in the Zhoushan fishing ground and adjacent waters. We found that there were 25 species of cephalopod being identified in the survey area, belonging to 3 orders, 8 families and 9 genuses, and shallow water species being dominant. The catches of Octopus variabilis and O. ocellatus were higher, respectively accounting for 34.93% and 30.06%. In addition, Loligo kobiensis, Sepiola birostrata, and so on accounted for a certain proportion. High catches occurred mainly in summer, it was higher in the fishing ground of Yangtze estuary and Zhoushan fishing ground; but in spring, the fishing ground of Yangtze estuary and Jiangwai fishing ground had a higher CPUE. In autumn, the occurrence rate of Cephalopods in Zhoushan fishing ground was higher than that in the fishing ground of Yangtze estuary. However, the fishing ground of Yangtze estuary had the highest CPUE. Cephalopods in winter investigation areas were not abundant, with disperse distribution, only appearing in few erect positions in the Yangtze estuary fishing ground.
Compared with the previous survey, the community structure of Cephalopods in this area had greatly changed. The previous dominant species, Sepiella japonica was replaced by the small epibenthic population.
|
Key words: Cephalopod, Species composition, Quantitative distribution, Zhoushan fishing ground and adjacent waters |