一、鱼种在越冬期间死亡的原因1.水体严重缺氧。到了冬季,水体会严重缺氧。这是因为水中浮游植物量少,光合作用减弱造成氧的供求失衡,产氧量小于消耗量;二是水体由于投饵、施肥及鱼类代谢废物积累,有机物多,大量消耗氧气;三是水中鱼种放养密度过大,引起缺氧;四是池塘保水性差, First, the species of fish died during the winter reasons 1. A serious water shortage of oxygen. In winter, water will be a serious lack of oxygen. This is because the amount of phytoplankton in the water is less and the weakened photosynthesis results in the imbalance between supply and demand of oxygen and the oxygen production is less than the consumption. Second, the water body consumes oxygen because of the accumulation of waste, fertilization and fish metabolic waste, Fish stocking density is too large, causing hypoxia; Fourth, poor water retention ponds,