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冬季北方池塘水温较低,而且随着气温的下降水面会结冰,鱼类的活动量减少,很少摄食或停止摄食,生长速度减慢,抗病能力下降,容易给养殖户造成严重的经济损失。要改善这一情况,冬季要从以下几个方面加强鱼类管理。一、水质的管理1.保证充足的溶氧。冬季浮游植物量少,光合作用产氧就不能保证鱼类的需求。可以通过施肥来增加浮游植物量。在氮、磷丰富的水体中浮游植物量高,每亩池塘每次施尿素和过磷酸钙各3~5千
In winter, the water temperature in northern ponds is low, and as the temperature drops, the water surface will freeze. The fish’s activity will decrease. Feeding less or stopping feeding will slow the growth and reduce the disease-resistant ability, which will easily cause serious economic problems for farmers loss. To improve the situation, winter management should be strengthened in the following aspects. First, the quality of water management 1. To ensure adequate dissolved oxygen. Less phytoplankton in winter, photosynthesis oxygen can not guarantee the needs of fish. The amount of phytoplankton can be increased by fertilization. Phosphorus in nitrogen and phosphorus-rich waters in the high amount of phytoplankton per mu of urea each application and superphosphate 3 to 5 thousand