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一、柳叶湖的鱼类柳叶湖是西洞庭围垦后留作调蓄、灌溉的垸内湖泊。湖水下泄沅江汇聚洞庭。由于江湖相通、许多鱼类又能在内湖自然繁殖,虽然人工放养近二十年,其天然鱼种类较多。据我们1982—1984年调查,该湖现有鱼类54种,隶属9目14科。其中鲤科鱼类38种,占70％;银鱼科、鮠科、鮨科各2种,分别占3.7％;鳀科、鳅科、鳗鲡科、针鱼科、鳢科、鲶科、合鳃科、塘鳢科、虾虎鱼科、刺鳅科各一种,分别占1.85％。二、天然经济鱼类在养殖湖泊中的变动从1982—1984年,我们结合冬捕,对柳叶湖天然鱼类的种群组成进行了逐年统计,结果如表1。统计资料指出,在柳叶湖放养鱼类产量逐年上升的同时,随着捕捞强度的加大,天然鱼类在总产量中也相
First, the willow lake fish Willow Lake west of Dongting reclamation for storage and irrigation, embankment within the lake irrigation. Yuanjiang Lake drain the convergence of Dongting. Due to the interlinked rivers and lakes, many fish can reproduce naturally in Neihu Lake. Although they are stocked for nearly two decades, they have more natural fish species. According to our survey of 1982-1984, there are 54 species of fish in the lake, belonging to 9 orders and 14 families. Among them, 38 species of cyprinid fish accounted for 70% of the total, while 2 species belonged to Silverfish, Trichostrongyridae and Trichosanthes, accounting for 3.7% of the total respectively. The families of Brachyura, Anguilla, Anguilla, Pinaceae, Gill Division, Tarsus Division, goby Division, each branch of loach families, accounting for 1.85%. Second, the natural economy changes in fish farms Lake from 1982 to 1984, we combined with winter catches, the natural population of Willow Lake fish population composition statistics, the results shown in Table 1. Statistics show that while the production of stocked fish in Willow Lake increases year by year, along with the increase of fishing intensity, the natural fish will also be in total output