嘉陵江有毒鱼类的分布研究

为了丰富人们对有毒鱼类的认知,结合8年的调查数据和已有资料对嘉陵江中有毒鱼类的种类、分布和食性进行研究。研究结果发现:在嘉陵江中有毒鱼类共计18种,隶属于4目6科17属,随着分类水平的变化(从目、科、属到种),有毒鱼类在不同分类级别下所占的比例逐渐降低。嘉陵江有毒鱼类中仅圆口铜鱼(Coreius guichenoti)和鳜(Siniperca chuatsi)分布于中下游,其余16种有毒鱼类分布于整个嘉陵江干流。Jaccard’s相似性分析表明各江段有毒鱼类分布的相似性极高,卡方(χ~2)检验结果显示各江段有毒鱼类分布无显著性差异(p0.05)。嘉陵江分布的有毒鱼类共4类,包括卵毒鱼类2种,血清毒鱼类1种,胆毒鱼类9种以及刺毒鱼类7种,其中鲇(Silurus asotus)既属于卵毒鱼类也属于刺毒鱼类,胆毒鱼类全部来源于鲤科鱼类,暂没有发现皮肤黏液毒鱼类。这18种有毒鱼类共包含7种食性类型,主要以杂食性和肉食性类型为主,分别占有毒鱼类种类数的38.89%和33.33%。通过本研究可知,有毒鱼类在嘉陵江中分布广泛,有毒鱼类种类和类别较多。该研究促进了人们对嘉陵江有毒鱼类相关知识的了解,为进一步研究嘉陵江有毒鱼类奠定了基础。

Study on Distribution of Ichthyotoxic Fish in the Jialing River

To enrich awareness of ichthyotoxic fishes for people, the species, distribution pattern and feeding habits of ichthyotoxic fishes in the Jialing River were studied according to our 8 years investigation results and the existed data. 18 species from 17 genera, 6 families and 4 orders of ichthyotoxic fishes were found in the Jialing River. With the changes of the taxonomy level (from order, family, genus to species), the proportion of ichthyotoxic fishes decreases gradually. Coreius guichenoti and Siniperca chuatsi are absent in the upstream, but the other ichthyotoxic fishes were distributed in whole mainstream of the Jialing River. Analysis of the Jaccard’s similarities indicated that ichthyotoxic fishes were homogeneous distributed in upstream, midstream and downstream in the Jialing River. No significant difference (p>0.05) were found for the distribution pattern of ichthyotoxic fishes by Chi-test. There were two species of ichthyootoxic fishes, one species of ichthyohemotoxic fishes, nine species of ichthyogallotoxic fishes and seven species of acanthotoxic fishes among the 18 ichthyotoxic fish species. The catfish (Silurus asotus) belongs to both ichthyootoxic and acanthotoxic fishes. The ichthyogallotoxic fishes were all from Cyprinidae (Cypriniformes). No ichthyocrinotoxic fishes were found in the Jialing River. Seven trophic guilds were included of the 18 ichthyotoxic fish species, the omnivorous and carnivorous were the dominant trophic guilds, accounting for 38.89% and 33.33% of the ichthyotoxic fish species, respectively. According to our study, we can know that ichthyotoxic fishes are widely distributed in the Jialing River, and there are many species and categories of the ichthyotoxic fishes were found. This study has promoted the understanding of ichthyotoxic fishes and laid the foundation for further study of them in the Jialing River.