禁渔初期长江上游江津段鱼类群落研究及禁渔效果分析

Study on Fish Communities and Analysis of Fishing Ban Effect in the Jiangjin Section of the Upper Yangtze River during the Early Stage of Fishing Ban

关键词:  长江十年禁渔  江津段  鱼类  群落结构  效果评估

Key words:  The 10-year fishing ban on the Yangtze River  Jiangjin section  Fish  Community structure  Effect evaluation

摘要:

为了解禁渔初期长江上游江津段鱼类群落结构现状,于2023年5月、9月对该水域进行调查。结果显示,调查捕获鱼类80种,隶属于4目12科51属,其中珍稀特有鱼类16种,数量占比为16.44%,重量占比为41.22%。鱼类群落以定居型、底层、杂食性、中小型鱼类为主；厚颌鲂(Megalobrama pellegrini)、瓦氏黄颡鱼(Pelteobagrus vachelli)为优势种；Shannon-Wiener指数、Margalef指数、Simpson指数和Pielou指数变化范围分别为2.32-3.31、5.18-7.08、0.83-0.95、0.44-0.61,表明江津段水域鱼类物种丰富且群落分布较为均匀；ABC曲线结果显示,江津段水域鱼类群落结构相对稳定,受干扰程度较低；随着禁渔政策的实施,江津江段鱼类群落结构稳定且维持在较高的生物多样性水平,资源衰退趋势得到一定缓解。

Abstract:

To understand the current status of the fish community structure in the Jiangjin section of the upper Yangtze River in the early stage of the fishing ban, surveys were conducted in this water area in May and September 2023. The results showed that 80 fish species were captured in the survey, belonging to 4 orders, 12 families, and 51 genera. Among them, there were 16 rare and endemic fish species, accounting for 16.44% of the total number and 41.22% of the total weight. The fish community was mainly composed of sedentary, bottom-dwelling, omnivorous, small and medium-sized fish. Megalobrama pellegrini and Pelteobagrus vachelli were the dominant species. The variation ranges of the Shannon-Wiener index, Margalef index, Simpson index, and Pielou index were 2.32 - 3.31, 5.18 - 7.08, 0.83 - 0.95, and 0.44 - 0.61 respectively, indicating that the fish species in the Jiangjin section were rich and the community distribution was relatively uniform. The results of the ABC curve showed that the fish community structure in the Jiangjin section was relatively stable and the degree of interference was low. With the implementation of the fishing ban policy, the fish community structure in the Jiangjin section was stable and maintained a high level of biodiversity, and the trend of resource decline was alleviated to a certain extent.