我国北方池塘越冬期间经常出现鱼体质下降及大量死亡的现象,严重制约着池塘养殖业的发展。因此,必须查明原因,注重提前预防。1鱼类越冬死亡的原因1.1水质原因:一方面,冰封期过长,水与空气接触很少,水体中溶解氧含量较少且水温较低,光线不足,导致水体中浮游植物繁殖量减少,光合 During the wintering period in the northern ponds of our country, the phenomena of the drop of fish body mass and the large amount of death often occur, which severely restricted the development of pond aquaculture. Therefore, we must identify the reasons, pay attention to early prevention. 1 reasons for the overwintering of fish death 1.1 water quality reasons: on the one hand, the ice period is too long, water and air contact with little dissolved oxygen in the water less and the water temperature is low, lack of light, resulting in reduced phytoplankton reproduction in water Photosynthesis