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1概述1．1鱼的特征:①变温低等脊椎动物;②用鳃呼吸,呼吸水中的DO(溶解氧),终生生活于水中;③体多呈纺锤形,常覆盖有保护性的鳞片;④以鳍运动。1．2历史:江浙一带的所谓“外荡养鱼”,原意即指河道养鱼。主要是指在天然河道里,选择水流缓慢,水位变动不大的河段,用竹箔拦截,投放鱼种利用天然饵料养鱼,这种养殖方式我国大约已有60多年的历史。始创于浙江绍兴一带。大致在1937年建
1 Overview 1.1 The characteristics of fish: ① low temperature vertebrates; ② gills breathing, breathing water DO (dissolved oxygen), life-long life in water; ③ mostly spindle-shaped body, often covered with protective scales; ④ to the fins movement. 1.2 History: Jiangsu and Zhejiang Provinces so-called “lingering fish”, the original meaning refers to the river fish. Mainly refers to the natural river, select the slow flow, small changes in the water level of the river, with bamboo foil interception, the use of natural feeding fish species fish, this farming method has about 60 years of history. Founded in Shaoxing, Zhejiang area. Built roughly in 1937