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益阳县通过水产资源考察,发现最为突出的问题是水产资源出现逆向变化,表现在:经济鱼类品种资源明显衰退,尤以鳊鲌亚科和鲴亚科中的青梢、红梢、银鲴等鱼类急剧减少;月鲤、鳤鱼、鳗鲡、胭脂鱼等濒临灭绝;资江鱼(俗名弥鱼)已经绝种;天然鱼捕捞量一九五二年2345吨,一九八一年下降到425吨,减少了百分之八十二;水生经济植物逐渐减少,尤以芡实、红菱、莲藕、茭白等剧减;龟、鳖等爬行动和虾、蟹等甲壳动物大大减少。六十年代,鲢、草、鳙三种鱼的性成熟期,鲢鱼为四龄,草、鳙均为五龄。由于水域变化,鱼种多为近亲繁殖,性成熟期提早了一年,个体大为减小。
Yiyang County, through the investigation of aquatic resources, found that the most prominent problem is the adverse changes in aquatic resources, manifested in: the apparent decline of economic fish species resources, especially in the subfamilies and the subfamilies of green shoots, red shoots, Such as juvenile common carp, bighead carp, eel, bream fish are on the verge of extinction; Zijiang fish (common name of fish) are extinct; natural fish catch in 1952 2345 tons, down to 425 in 1981 Ton, a decrease of 82%; aquatic economic plants gradually reduced, especially in real, red diamonds, lotus root, white rice and other drastic reduction; turtles, turtles and other crawling and shrimp, crabs and other crustaceans greatly reduced. In the sixties, silver carp, grass, gall three kinds of fish sexual maturity, silver carp for the fourth age, grass, gall are five years old. Due to changes in waters, most species of inbreeding fish, sexual maturity one year earlier, the individual greatly reduced.