论文部分内容阅读
为了解三峡库区蓄水后小江流域鱼类群落现状及其历史变化,于2016年春季(5月)、秋季(9月)和冬季(12月)开展了小江鱼类调查。共调查到鱼类37种,隶属于6目11科;种类组成以鲤形目为主,占总数的64.86%,其中黑尾■Hemiculer tchangi和岩原鲤Procypris rabaudi为长江上游特有种类;草鱼Ctenopharyngodon idellus、赤眼鳟Squaliobarbus curriculus、■Elopichthys bambusa、鲫Carassius auratus、鲤Cyprinus carpio、鲢Hypophthalmichthys molitrix、鳙Aristichthys nobilis和黑尾■构成小江主要经济鱼类。对比历史资料分析显示:两次调查结果相似性指数为0.45(为中等不相似);特有种鱼类退化明显:主要经济鱼类组成发生了改变;土著鱼类物种多样性和资源量均呈明显下降趋势,而适应于静水或缓流水环境的鱼类呈上升趋势。推测水坝建设、过度捕捞及不合理的采砂活动等因素是导致变化的主要原因。结果建议,合理设置水坝(汉丰湖)调水机制,对于保护该水域土著鱼类资源具有重要意义。
In order to understand the current status and historical changes of fish communities in the Xiaojiang River basin after the impoundment of the Three Gorges Reservoir, a survey of small river fish was conducted in spring (May), autumn (September) and winter (December). A total of 37 species of fish were found, belonging to 6 orders and 11 families. The species composition was predominantly Cyprinidae, accounting for 64.86% of the total. Among them, Hemiculer tchangi and Procypris rabaudi belonged to the endemic species in the upper reaches of the Yangtze River. Ctenopharyngodon idellus Squaliobarbus curriculus, Elopichthys bambusa, Carassius auratus, Cyprinus carpio, Hypophthalmichthys molitrix, Aristichthys nobilis, and Black-tailed squid constitute the major economic fish of the Xiaojiang River. Comparative historical data analysis showed that the similarity index of the two surveys was 0.45 (moderately dissimilar); the endemic species degenerated significantly: the composition of the major economic fish changed; the diversity and resources of indigenous fish species were significant Declining trend, while fish adapted to still water or slowed water environment are on the rise. Speculated that dam construction, over-fishing and irrational sand mining activities and other factors are the main reasons for the change. As a result, it is suggested that the rational establishment of dam (Hanfeng Lake) water diversion mechanism is of great significance for the protection of indigenous fish resources in this area.