论文部分内容阅读
对富营养条件下太湖湖鲚消化道食物解剖观察,用个体数量百分比为指标,定量分析了太湖春、秋两季153尾湖鲚的食物组成。结果表明,2004年秋季湖鲚食物中枝角类占89.77%±13.69%,桡足类占7.84%±11.53%,在枝角类中象鼻蚤组成比例最高,占85.66%±15.48%;2005年春季湖鲚食谱中枝角类占79.35%±11.42%,象鼻蚤占42.31%±19.26%,桡足类占19.97%±10.78%。由此可见,春、秋两季湖鲚在食物组成上无明显差异,都以枝角类、尤其是象鼻蚤为主。与此同时,对太湖新银鱼食物组成分析得出该鱼以食桡足类为主,太湖湖鲚与银鱼在食物组成上有较大差异。通过分析认为,利用翘嘴红鲌、鳜鱼等肉食性鱼类来控制湖鲚产量的增加,对缓解太湖水体富营养化程度有一定的积极作用。
The anatomy of Digestive tract of Taihu Lake under eutrophic condition was analyzed. The food composition of 153 Ophiopogon japonicus in spring and autumn of Taihu Lake was quantitatively analyzed using the percentage of individuals as an index. The results showed that in the autumn of 2004, the percentage of cladoceran in food was 89.77% ± 13.69%, and that of copepods was 7.84% ± 11.53%. The highest percentage of them was 85.66% ± 15.48% in cladoceras. In spring, the number of branches and branches in the recipe of Lake 鲚 was 79.35% ± 11.42%, 42.31% ± 19.26% and 19.97% ± 10.78% respectively. Thus, the spring and autumn two seasons Lake 鲚 no significant difference in food composition, all with Cladocera, especially Trichosanthes flea-based. At the same time, the composition analysis of the fresh silverfish in Taihu Lake showed that the fish mainly consisted of copepods, and there was a big difference in the food composition between the Taihu Lake and the whitebait. Through the analysis, the use of carnivorous fish such as red snapper and bighead carp to control the increase of the output of lakes and shrubs will play a positive role in alleviating the eutrophication of Taihu Lake.