汉江中下游产漂流性卵鱼类早期资源现状的初步研究

为了解汉江中下游江段的水文变化特点与鱼类早期资源分布状况,2009年6～8月在沙洋断面开展了汉江中下游产漂流性卵鱼类早期资源现状的调查。结果表明,汉江沙洋站以上可监测到的152.28km干流江段中共有3个产卵场,产卵场总长度为42.12km,占江段总长的27.7%。产卵总量为56601.9万粒,产漂流性卵鱼类约有21种,其中拟尖头鲌、蛇鮈、双斑副沙鳅、翘嘴鲌、吻鮈、赤眼鳟等为优势种。产漂流性卵鱼类的产卵次数和产卵量与江水的流速、温度、透明度、涨落水持续时间等多个因素都有一定的关联。近5年来,汉江中下游产漂流性卵鱼类的产卵量因为各种因素的影响呈现出逐年下降的趋势,产卵场的位置也有所改变。本研究旨在为水利开发与水生态环境以及鱼类资源保护提供基础资料。

Preliminary Study on the Larval Resources of Fishes Spawning Drifting Eggs in the Middle and Lower Reaches of the Hanjiang River

We investigated the status of the larval resources of fishes with drifting eggs of the middle and lower reaches of the Hanjiang River in the Shayang section during June to August in 2009.The results indicated that three spawning sites involved in 42.12km existed in the mainstream of 152.28km up the Sanyang section. The total numbers of eggs are 5.66 ×108 ind..21 species of fishes breed drifting eggs found, in which Culter oxycephaloides, Saurogobio dabryi, Parabotia bimaculata, Culter alburnus, Rhinogobio typus, Squaliobarbus curriculus are dominant species. Some obviously interactions behaved between the spawning numbers by top of egg numbers in a breed referred to the fishes spawning with the drifting eggs and hydrological factors contained the flux, water temperature, transparency, continues time of a flood and so on. A mixed and combined impacted imposed by human-referred effects led to the scale of spawning with drifting eggs of fishes sharply declined year by year in the recent 5 years in turns the spawning sites changed at the same time. According to promptly know the kinships between current distribution situations of fishes spawning with drifting eggs and change characters of hydrological essences in the middle and lower of Hanjiang River, it could provide the basic data for the purpose of water settings and fish resources protection and the development of hydro-power.