嘉陵江不同江段蛇(鱼句)的食性分析
Analysis on the Feeding Habits of Saurogobio dabryi in Different Reaches of Jialing River

中文摘要：2015年和2016年的10—11月，在嘉陵江上游（广元）、中游（蓬安）、下游（合川）采集210尾蛇(鱼句) Saurogobio dabryi，采用传统镜检法对其食性进行研究。结果表明：嘉陵江蛇(鱼句)属于杂食性鱼类，饵料生物包括5大类（79小类）；聚类分析表明，出现率（F%）、数量百分比（N%）和相对重要性指数（IRI%）在衡量食物对嘉陵江蛇(鱼句)的重要性方面表现一致，但基于质量百分比（W%）的食物重要性结果与前三者之间的差异有统计学意义。4种指数显示，上游和中游江段蛇(鱼句)均以动物性饵料为主，为偏肉食性的杂食性鱼类，下游江段蛇(鱼句)以藻类为主，为偏植食性的杂食性鱼类。选用W%对其食性进行不同江段之间比较，聚类分析表明中游与上游和下游存在显著差异（d>0.3）；Schoener重叠指数比较显示，不同江段蛇(鱼句)摄食的饵料生物存在空间差异（C xy<0.60）。研究认为蛇(鱼句)的食性具有较强的地域性和可塑性，可能是对不同江段水生生态环境适应的结果。
英文摘要：The samples of stomach content of Saurogobio dabryi were collected at different reaches in Jialing River from October to November of 2015 and 2016, and the food composition was investigated based on the analysis of stomach contents. The results showed that S. dabryi was an omnivorous fish, and 5 broad diet categories (79 small diet categories) were identified. Cluster analysis showed that the occurrence rate (F%), numerical percentage (N%) and percent index of relative importance (IRI%) were consistent in measuring the contribution of each food category to S. dabryi. However, there was a significant difference between the food importance results based on weight percentage (W%) and the top three. Based on the 4 indices determined above, the dominant composition of animal bait in the stomach content of S. dabryi from the upper and midstream indicated that S. dabryi was carnivorous omnivorous in these reaches. By constrast, S. dabryi from the downstream was found to be phytophagous omnivorous according to the dominant composition of algae in the stomach content. Comparison of W% among the S. dabryi from different reaches revealed significant differences between the food composition of the middle reaches with that of the upstream and downstream (d>0.3). The Schoener overlap index showed that the food composition of the fish varied between different reaches (C xy<0.60). These results indicated that the feeding habits of S. dabryi had strong regionalism and plasticity, and this might provide an explanation for the adaptation of S. dabryi to different aquatic ecological environments. 2019,38(1): 68-76 收稿日期：2018-03-28 分类号：Q959.4 基金项目：国家自然科学基金项目（51779210）；四川省教育厅重大培育项目（17CZ0035）；四川省科技厅项目（2018KZ0060） 作者简介：吕振宇(1993—),男,硕士研究生,研究方向:鱼类生态学,E-mail:13458237276@163.com *通信作者：曾燏,E-mail:zengyu@cwnu.edu.cn;熊小琴,E-mail:xiongxiaoqinxxq@163.com 参考文献： 陈安慧. 2014. (鱼句)亚科鱼类的分子系统发育关系研究[D]. 上海: 复旦大学. 陈大刚. 1997. 渔业资源生物学[M]. 北京: 中国农业出版社. 陈颖涵. 2013. 北部湾主要鱼类食性的初步研究[D]. 厦门: 厦门大学. 程炜轩. 2006. 自然水体唐鱼的栖息环境及其食性分析[D]. 广州: 暨南大学. 丁淑荃, 万全, 李飞, 等. 2013. 蛇(鱼句)精子结构研究[J]. 安徽农业大学学报, 40(6): 959-963. 韩茂森, 束蕴芳. 1995. 中国淡水生物图谱[M]. 北京: 海洋出版社. 何学福,