摘要
根据1999—2002年和2007—2009年各年冬季共7个航次的底拖网调查资料,对黄海大头鳕的种群特征及其年际变化进行了研究。结果表明,大头鳕种群相对密度升高,优势年龄由1龄组升高到3龄组,雌性性成熟比例升高;两个调查阶段大头鳕的体长-体重关系分别为W=4.564×10-3L3.333和W=1.550×10-2L2.994;主要饵料均为甲壳类,饵料多样性指数(H′)从1.0升高到1.9,表明大头鳕生境宽度增加。大头鳕种群特征的变化可能与气候变化、黄海生态系统食物网结构的变化以及渔业保护有关。与20世纪80年代相比,两个调查阶段的大头鳕年龄结构仍然较为简单,且其分布范围较窄,资源易受外界环境变化的影响。因此,需关注环境因子和捕捞压力变化对黄海大头鳕资源的影响,制定合理养护措施,促进资源的可持续利用。
Variations in population characteristics of the studied using data from seven winter surveys in 1999--2002 Pacific cod （Gadus macrocephalus） in the Yellow Sea were and 2007--2009. The results showed that the relative popula- tion density increased from 1.0kg/h to 11.7kg/h, and the dominant age increased from 1 year old to 3 years old over the surveyed periods. Moreover, proportions of females at sexual maturity increased from 21.9% to 67.3%. Body weight-length relationships of male and female individuals were insignificantly different （P〉0.05）, and the pooled data for these two pe- riods can be fitted using two exponential functions, i.e., W = 4.564× 10-3 L3.333 in 1999--2002 and W = 1.550× 10-2 L2.994 in 2007--2009. Stomach contents analysis showed that crustaceans were the dominant diet in both periods, although with more species foraged by the Pacific cod in recent years. This may have caused an increase in its niche width. The changes in population characteristics were attributed to the climate changes, variations in food web and the fishery management strategies enforced in the Yellow Sea. Compared to the data from 1980s＇, the distribution of the Pacific cod in the Yellow Sea is still limited and their age structure is simple. Therefore, the Pacific cod stock is sensitive to the changes in fishing intensity and the environment stressors, thus rational protective measures should be developed for the sustainable utiliza- tion of this species.
出处
《海洋与湖沼》
CAS
CSCD
北大核心
2012年第5期924-931,共8页
Oceanologia Et Limnologia Sinica
基金
全球变化研究重大科学研究计划项目,2010CB951204号
国家高技术研究发展计划(863)项目,2009AA09Z401号
国家自然科学基金项目,40906086号
山东省泰山学者专项基金项目
关键词
大头鳕
生物学特征
食性
年际变化
黄海
Pacific cod Gadus macrocephalus, Biological characteristics, Feeding habits, Interannual changes, Yellow Sea
作者简介
李忠炉，博士，E-mail：mreco．1izhonglu@gmail．com
通讯作者：金显仕，博士，研究员，E-mail：jin@ysfri．ac．cn
