三峡库区干流鱼类资源现状与物种多样性保护

为掌握三峡库区干流现有鱼类种类组成和物种多样性状况,2013-2015年在三峡库区干流涪陵、云阳、巫山和秭归4个江段开展渔获物调查,分析了该区域的鱼类资源现状及物种多样性。结果表明,调查期间共收集到鱼类84种,隶属于5目、13科,以鲤形目和鲇形目为主,其中包括厚颌鲂(Megalobrama pellegrini)、岩原鲤(Procypris rabaudi)、圆口铜鱼(Coreius guichenoti)等12种长江上游特有鱼类,鱼类种类数没有显著变化;多样性分析显示,以相对重要性指数(IRI)大于2%为标准,三峡库区鱼类群落优势种共15种,其中飘鱼(Pseudolaubuca sinensis)和黑尾歺又鱼(Hemiculter nigromarginis)的优势度最高。渔获物调查表明,三峡库区日平均单船产量为8.93kg;鱼类群落的Shannon-Wiener多样性指数(H)和Simpson优势度指数(D)呈现逐年增加趋势。基于本调查结果,提出了栖息地恢复、严格控制捕捞强度等措施,以保护三峡库区干流的鱼类多样性。

Fish Resource Status and Biodiversity Conservation in the Main Channel of Three Gorges Reservoir

To better understand the status of fish resources in the mainstream of the Three Gorges Reservoir, we carried out a fishery resource investigation in the Fuling, Yunyang, Wushan and Zigui sections August-September and November-December in 2013, 2014 and 2015. The investigation focused on fish species composition, ecotype, dominant species, catch size and diversity. The study provides basic data for fishery resource conservation and sustainable utilization as well as ecological restoration in Three Gorges Reservoir. During the survey, data on 47,748 fish, totaling 1,849.69 kg, were obtained from 203 fish catch boats. A total of 84 species, including 12 species endemic to the upper Yangtze River, were identified, representing 13 families and 5 orders and dominated by Cypriniformes and Siluriformes. The number of fish species did not change significantly from previous studies and the primary ecotypes included limnophilic (15 species), rheophilic (35 species) and eurytopic (34 species). There were 15 species with an index of relative importance (IRI) > 2% and Pseudolaubuca sinensis and Hemiculter nigromarginis displayed the highest IRI. The catch per unit fishing effort (CPUE) was 8.93 kg/boat-day. The Shannon-Wiener diversity index (H) and Simpson dominance index (D) trended upward year by year. Based on the results of the survey, habitat restoration and strict control of fishing intensity are recommended to protect fish diversity in the main channel of Three Georges Reservoir.