%0 Journal Article %T 太湖新银鱼、鲚鱼的食性比较及相互影响分析 %T Comparison of food composition and analysis on mutual effects between Neosalanx tangkahkeii taihuensis Chen and Coilia ecten taihuensis Yen et Lin in Lake Taihu %A 刘恩生 %A 鲍传和 %A 吴林坤 %A 曹萍 %A LIU,Ensheng %A BAO,Chuanhe %A Wu Linkun %A CAO,Ping %J 湖泊科学 %J Journal of Lake Sciences %@ 1003-5427 %V 19 %N 1 %D 2007 %P 103-110 %K 太湖;太湖新银鱼;鲚鱼;食性比较;数量组成比例;饵料重叠系数;相同食物组成比 %K Lake Taihu;Neosalanx tangkahkeii taihuensis Chen;Coilia ectenes taihuensis Yen et Lin;food composition percentage in number;food overlap coefficient;resemble food composition %X 在太湖, 通过对263个太湖新银鱼和鲚鱼胃含物样本的食物组成分析和比较, 研究了两种鱼类间的食物关系;并结合太湖历年鱼类渔获量资料, 对渔获量变化间可能存在的相互影响进行了偏相关分析.结果表明:太湖新银鱼在4月份的食物中以桡足类为主, 占个数的70.11%±10.57%, 其次是枝角类, 为29.84%±10.62%, 轮虫的数量极少, 仅占0.05%±0.11%;在4月份1+鲚鱼的食物中以枝角类为主、占79.35%±11.42%, 桡足类占19.97%±10.78%, 而轮虫和虾的数量很少, 分别占0.49%±0.45%和0.20%±0.44%.而在9-10月份0+鲚鱼的食物中.枝角类占89.77%±13.69%, 桡足类占7.84%±11.53%, 轮虫占2.39%±4.95%;用Pianka提出的公式, 计算两种鱼类在4月份5个采样点的饵料重叠系数平均为0.4739±0.2810, 没有达到Keast提出的Ojk>0.7的严重重叠水平;计算5个采样点的相同食物组成比平均为46.42%±20.32%, 和饵料重叠系数接近.而偏相关分析表明:两种鱼类数量变化间的相关关系是负向的, 且随着鱼类密度的增加, 负相关关系的显著水平有不断提高的趋势.如1973-1984年期间的负相关关系远没有达到显著水平(r=-0.2531 p=0.584), 而1985-2004年期间的负相关关系接近显著水平(r=-0.4395 p=0.101).分析认为:太湖新银鱼和鲚鱼的食物虽有重叠, 但通常情况下食物竞争并不激烈;种群数量变化间的相互影响是负向的, 没有达到显著水平.可能仅在两种鱼类密度很高时, 激烈地食物竞争才会发生、并主要表现为对哲水蚤和剑水蚤的竞争;且数量间负向的相互影响有加强趋势. %X During April in 2004 and November and October in 2005, based on the food composition investigation for 263 food samples of Neosalanx tangkahkeii taihuensis Chen and Coilia ectenes taihuensis Yen et Lin and the correlative analysis of the changes of fish catches, the food relationship and the mutual effects between the two fishes were studied in Lake Taihu.Results showed that:Neosalanx tangkahkeil taihuensis Chen mainly fed on Copepoda accounting for 70.11% 3±10.57% in its food, Cladocera accounting for 29.84% 3±10.62% and Rotifera only accounting for 0.05 % 3±0.11% in the investigation during April ;while in the same time investigation, Coilia ectenes taihuensis Yen et Lin mainly fed on Cladocera accounting for 79.35% 3±11.42% in its food, Copepoda accounting for 19.97% 3±10.78%, and Rotifera and shrimp respectively accounting for 0.49% 3±0.45% and 0.20% 3±0.44% and in the investigation during November and October;Cladocera accounted for 89.77% 3±13.69% in its food, Copepoda accounted for 7.84% 3±11.53%, and Rotifera only accounted for 2.39% 3±4.95%.The average food overlap coefficient in 5 sampling points between the two fishes was 0.4739 ±0.2810 which did not reached to the significant overlap level during the April investigation.The resemble food composition was 46.42% ±20.32%.The partial correlative analysis showed that:there was negative correlation between the catches of the two fishes, but not significant;there was the trend of the significant level of the negative correlation getting high and high with the catches of the two fishes increasing.For example, the significant level of the negative correlation was r =- 0.4395 p =0.101 during the periods from 1973 to 1984 and was r =-0, 4395 p =0.101 during the periods from 1985 to 2004.The analysis might show that:the main food of the two fishes was different so that in common ecolog- ical conditions there was nearly not fiercely food competition between the two fishes.But with their density getting high there would be food competition between them and the food competition was mainly focused on the Copepoda. %R 10.18307/2007.0116 %U http://www.jlakes.org/ch/reader/view_abstract.aspx %1 JIS Version 3.0.0