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武汉市新洲区涨渡湖渔业生产是以人工投放、天然生长为主,鱼类资源自然增殖为辅的粗放型管理模式进行。1992~2004年捕捞产量变幅范围为(3.69~50.61)×104kg,其中有9个年份变幅在10×104kg以上;产品收入变幅范围为(2.77~201.77)×104元,其中有6个年份变幅在50×104元以上。目前涨渡湖鱼类共有47种,与历史最高种数比较,下降了38.2%。渔获物组成中,放养鱼类占80%以上,人工放养是目前涨渡湖鱼类补充群体的主要来源;鱼类年龄结构简单,主要经济鱼类低龄化趋势严重;主要品种鲢、鳙的生长速度慢于同类湖泊。江湖隔绝和长期的人工增养殖生产作业方式,是导致涨渡湖鱼类区系逐渐简单化,鱼类多样性下降的重要原因。
The fishery production of Zhangdu Lake in Xinzhou District of Wuhan City is carried out by the extensive management mode of artificial feeding, natural growth and supplementation of natural fish resources. From 1992 to 2004, the range of variation of fishing yield was (3.69 ~ 50.61) × 104kg, of which, the amplitude was above 10 × 104kg in 9 years; the range of product income was (2.77 ~ 201.77) × 104, of which 6 Year change in 50 × 104 yuan or more. At present, there are 47 species of fish in the Jhongdu Lake, down 38.2% from the highest number in history. Catches accounted for more than 80% of the fish stock, and artificial stocking was the main source of the fish supplement population for the current Zhangduhu Lake. The age structure of fish was simple, and the major economic fish tended to become younger. The major species of silver carp, Growth slower than similar lakes. Isolated rivers and lakes and long-term artificial aquaculture production practices, leading to the gradual simplification of fish fauna in the Yellow River Delta, an important reason for the decline in fish diversity.