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为了解长江上游宜宾江段鱼类群落结构和渔业捕捞现状及变化趋势,为物种和资源保护提供依据,该文对宜宾江段的流刺网和小钩等主要作业渔具的渔获物进行了调查,对渔获物种类组成、捕捞规格和单位捕捞努力量渔获量等进行了统计分析.结果表明:在宜宾江段共采集到鱼类49种,隶属于3目10科29属,以鲤形目和鲇形目鱼类为主.圆口铜鱼、瓦氏黄颡鱼、异鳔鳅鮀、宜昌鳅鮀和蛇鮈为该江段的优势种.采集到长江上游特有鱼类11种,占鱼类总种数的22.4%,其中一半以上的特有鱼类为偶见种.宜宾江段渔业捕捞规格普遍偏小,大部分捕捞个体体质量在100g以下,体长在150mm以下.该江段流刺网和小钩的单位捕捞努力量渔获量仅为每船1~2kg/d.宜宾江段渔业资源已严重衰退,许多特有鱼类变为偶见种,渔业捕捞渔获量偏低,捕捞规格偏小,建议采取休鱼等措施,促进物种和资源的保护.
In order to understand the fish community structure, the current situation and trend of fishing in the Yibin section of the upper reaches of the Yangtze River, and provide the basis for the species and resource conservation, this paper conducted a survey on catches of main operating gear such as gill nets and hooks in the Yibin section The results showed that 49 species of fish were collected in Yibin River Section, belonging to 3 orders, 10 families and 29 genera, Cypriniformes and Halibut fishes were dominant in this section.The round-necked copper fishes, Valvoline fishes, Catfish loach, Yichang loach and Snake bream were the dominant species in this section of the Yangtze River. Species, accounting for 22.4% of the total number of species of fish, of which more than half of the endemic species of fish are occasional species. Yibin section of the fishing fishing generally smaller size, most of the individual fishing body weight in 100g, body length below 150mm. The catches of fishing effort per unit of nematodes and small hooks in this section are only 1 ~ 2 kg / d per boat. The fishery resources in Yibin section have been seriously deteriorated. Many endemic species of fish become occasional species. The quantity is low, fishing specifications are small, it is recommended to take measures such as rest fish to promote the protection of species and resources.