摘要
为了探明长江上游向家坝至宜宾44 km江段鱼类在枯水期(1—4月)的分布特征,2006—2012年期间采用裂波式探鱼仪BioSonics DT-X对该江段进行了7次水声学调查,并使用声学多普勒流速剖面仪(ADCP)采集流速等环境特征数据,此外,还在2011年3月同期进行试验性捕捞。水声学探测目标(Max.(TSc)≥-45 dB)的平均强度为(-42.32±5.02)dB,推算平均体长为22.71 cm。试验性捕捞共采获20种鱼类,平均体长21.31 cm。鱼类在研究区域呈现聚集分布的特征,主要分布在横河口、岷江口、南广河口三处河口以及打铁窝、李家沱两处深水区。分析认为枯水期该江段鱼类对环境有一定的选择性,通常栖息在水体深、流速小且弗劳德数(Fr)也较小的位置。
To ascertain the spatial distribution characteristic of the fish which were below Xiangjiaba Dam with the length of 44 km, seven hydroacoustic surveys were conducted by using BioSonics DT -X echosounder in dryseason of January-April during 2006-2012 .Meanwhile hydraulic data were gained by using ADCP and capture surveys were carried out in March 2011.The results indicated as follows: (1) Twenty fishes were gained in the capture surveys .The standard length of fi-shes were from 10 cm to 30 cm with the mean of 21.31 cm.(2) The result of the hydroacoustic surveys showed that the mean target strength was (-42.32 ±177;5.02)dB and the mean length was 22.71 cm.(3) The fishes mostly distributed in the estuaries of Heng River , Jinsha River and Nanguang River , and the deep reaches of Datiewo and Lijiatuo , particular-ly.(4) Fishes chose the habitats where the velocity magnitude and Froude number were lower with deeper depth .
出处
《淡水渔业》
CSCD
北大核心
2014年第1期53-58,共6页
Freshwater Fisheries
基金
中国水产科学研究院基本科研业务费(2012A0103)
农业部-中国长江三峡集团公司白鲟系列项目