文献类型： 外文期刊

作者： Zhang, B. ¹ ; Tang, Q. ¹ ; Jin, X. ¹ ;

作者机构： 1.CAFS, Yellow Sea Fisheries Res Inst, Key Lab Sustainable Utilizat Marine Fishery Resou, Qingdao 266071, Peoples R China

关键词： trophic level;decadal variations;high trophic levels;Yellow Sea and Bohai Sea ecosystem

期刊名称：JOURNAL OF MARINE SYSTEMS （ 影响因子：2.542； 五年影响因子：3.136 ）

ISSN： 0924-7963

年卷期： 2007 年 67 卷 3-4 期

页码：

收录情况： SCI

摘要： A total of 2759 stomachs collected from a bottom trawl survey carried out by RN "Bei Dou" in the Yellow Sea between 32 00 and 36 30N in autumn 2000 and spring 2001 were examined. The trophic levels (TL) of eight dominant fish species were calculated based on stomach contents, and trophic levels of 17 dominant species in the Yellow Sea and the Bohai Sea reported in later 1950s and mid-1980s were estimated so as to be comparable. The results indicated that the mean trophic level at high trophic levels declined from 4.06 in 1959-1960 to 3.41 in 1998-1999, or 0.16-0.19-decade 1 (mean 0.17-decade 1) in the Bohai Sea, and from 3.61 in 1985-1986 to 3.40 in 2000-2001, or 0.14-decade 1 in the Yellow Sea; all higher than global trend. The dominant species composition in the Yellow Sea and the Bohai Sea changed, with the percentage of planktivorous species increases and piscivorous or omnivorous species decreases, and this was one of the main reasons for the decline in mean trophic level at high tropic levels. Another main reason was intraspecific changes in TL. Similarly, many factors caused decline of trophic levels in the dominant fish species in the Yellow Sea and the Bohai Sea. Firstly, TL of the same prey got lower, and anchovy (Engraulis japonicus) as prey was most representative. Secondly, TLs of diet composition getting lower resulted in not only decline of trophic levels but also changed feeding habits of some species, such as spotted velvetfish (Erisphex pottii) and Trichiurus muticus in the Yellow Sea. Thirdly, species size getting smaller also resulted in not only decline of trophic levels but also changed feeding habits of some species, such as Bambay duck (Harpodon nehereus) and largehead hairtail (Trichiurus haumela). Furthermore, fishing pressure and climate change may be interfering to cause fishing down the food web in the China coastal ocean. (c) 2006 Elsevier B.V All rights reserved.