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增氧机是目前淡水渔业中广泛使用的一种设备。因为氧气是鱼类生活所必需的,不过鱼只能呼吸溶解于水中的氧气,而水中溶解的氧气要比空气中的氧少得多,空气中的含氧量约为21%,而水中的氧气一般不到百万分之十。在自然状态下水中溶解氧主要来源于浮游植物的光合作用和大气对水面的扩散,前者约占90%。大量的氧气是由水生植物、浮游生物、有机肥料、饲料残渣、鱼体排泄物等池底堆积物的腐败分解所消耗,鱼类的消耗仅占5—10%。一旦水中缺氧,水质就会腐败,鱼类呼吸就困难,食欲减退,饲料系数增加,增肉率降低。严重缺氧,鱼就会“浮头”或窒
Aerator is a widely used device in freshwater fisheries. Because oxygen is essential for fish’s life, fish can only breathe oxygen dissolved in water, and dissolved oxygen in water is much less than the oxygen in the air, which is about 21% oxygen, while in water Oxygen is generally less than ten parts per million. In the natural state of dissolved oxygen in water comes mainly from photosynthesis of phytoplankton and the atmosphere on the surface of the water, the former about 90%. Large amounts of oxygen are consumed by spoilage of bottom sediments such as aquatic plants, plankton, organic fertilizers, feed residues, fish excretions and the like, accounting for only 5-10% of fish consumption. Once the water is lack of oxygen, the water quality will be corrupt, the fish will be difficult to breathe, the appetite will be reduced, the feed coefficient will increase and the meat yield will decrease. Severe hypoxia, the fish will be “floating head” or stifled