金沙江中游干流鱼类资源现状及梯级开发对其产生的影响分析

THE CURRENT STATUS OF FISHERY RESOURCES IN THE MIDDLE REACHES OF JINSHA RIVER AND THE IMPACT OF CASCADE DEVELOPMENT

在梳理金沙江中游水电开发现状的基础上,于2021年12月(枯水期)、2022年3-4月(平水期)、2022年7-8月(丰水期)对金沙江中游的鱼类资源进行了调查分析,以评估金沙江中游水电梯级开发对鱼类的影响。结果显示,调查共计采集鱼类47种,隶属于3目9科34属,其中8种国家二级重点保护种、14种外来物种。金沙江中游干流可分为梨园-龙开口河段与鲁地拉-观音岩和金沙-银江河段3组,鱼类群落结构差异显著(P<0.05),梨园、阿海、金安桥、龙开口河段鱼类组成以土著亲流型鱼类为主,优势种为细鳞裂腹鱼(Schizothorax chongi)、短须裂腹鱼(Schizothorax wangchiachii)等裂腹鱼科鱼类及圆口铜鱼(Coreius guichenoti);鲁地拉、观音岩河段鱼类组成以土著亲流型鱼类与外来广适型鱼类为主,优势种为鲫(Carassius auratus auratus)、?(Hemiculter leucisculus)、短须裂腹鱼;金沙、银江河段鱼类组成以为静水、广适型的外来小型鱼类为主,优势种为麦穗鱼(Pseudorasbora parva)、高体鳑鲏(Rhodeus sinensis)。与历史资料相比,金沙江中游鱼类存在小型化及高原区系转变为平原区系趋势。研究补充了金沙江中游鱼类资源现状的基础数据,并提出保护建议,以期为该江段鱼类资源管理与保护提供科学依据。

In order to investigate the characteristics of fish resources in the middle reaches of the Jinsha River,surveys were conducted in the mainstreams and its tributaries in December 2021(dry season),March-April 2022(normal season),and July-August 2022(wet season).The results showed a total of 47 fish species,belonging to 3 orders,9 families,and 34 genera,Among them,8 species were classified as national second level key protected species,and 14 were identified as alian species.This study analyzed the species composition,ecological types,community similarity,and biodiversity of fish.The mainstream of the middle reaches of the Jinsha River can be divided into three groups:the Liyuan-Longkaikou section,the Ludila-Guanyinyan section,and the Jinsha-Yinjiang section.Significant differences in fish communities were observed in these groups(P<0.05).The Liyuan,Ahai,Jinanqiao,and Longkaikou sections predominantly featured indigenous hydrophilic fish,with dominant species such as Schizothorax chongi,Schizothorax wangchiachii,and Coreius guichenoti.The Rudila and Guanyinyan sections are mainly composed of indigenous riffle fish and alian Eurytopic fish,with dominant species including Carassius auratus auratus,Hemiculter leucisculus,and Schizothorax wangchiachi.The Jinsha and Yinjiang river sections exhibited a fish composition primarily composed of small,exotic,calm water and Eurytopic species,with dominant species like Pseudorasbora parva and Rhodeus sinensis.Compared with the historical data,a trend of miniaturization in fish and a transition from plateau flora to plain flora in the middle reaches of the Jinsha River were observed.This study supplements the basic data on the current status of fish resources and proposes protection suggestions,aiming to provide a scientific basis for the management and protection of fish resources in the specified section of the river.