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兰州段家滩有养殖水面320亩,原为黄河支流截流而成,分为6个串连鱼池进行鱼类养殖。1974年前,因鱼池距黄河主干道较近,增添池水较为容易。此后,因河道整修,鱼池距黄河主航道变远,基本上成为死水鱼池;而且因纳入军卫校、涂料所、气象局等单位的污水,每昼夜流入504吨,实际上成为污水鱼塘。污水养鱼最突出的问题是:在投放鱼种较多的情况下容易缺氧,其后果往往是轻则引起鱼浮头;重则引起鱼类大量死亡。特别是冬季池面覆冰,隔绝了氧气的补充,阻隔了浮游植物的光合作用,极易引起缺氧,造成鱼类窒息死亡,
Section Lanzhou section of the beach has 320 acres of aquaculture water, the Yellow River tributary was originally cut off, divided into 6 fish ponds connected in series. Before 1974, due to fish ponds close to the Yellow River main road, it is easier to add water. Since then, due to river renovation, the fish ponds have become far away from the main channel of the Yellow River and have basically become dead fish ponds. Due to the integration into the military health schools, coating plants, weather bureau and other units, 504 tons of sewage are circulated every day and night, effectively becoming sewage ponds. The most prominent problem with sewage water fish farming is that it is easy to lose oxygen in the case of more fish species, and the consequences are often as low as causing floating fish heads; heavy fish also cause a large number of deaths. In particular, the winter pool icing, isolated from the oxygen supplement, blocking the photosynthesis of phytoplankton, easily lead to hypoxia, resulting in the death of fish suffocation,