大家都知道,鱼儿是离不开水的。可是,我要告诉大家的是,鱼儿更离不开氧。你看到过鱼儿跑到水面呼吸的现象吗?这种现象常被养鱼的人称为“鱼浮头”(右图)。一旦鱼池里出现了这样的现象,那一定是水中缺氧了。那什么情况下会出现水中缺氧呢?如果你仔细观察的话,就会发现水中缺氧通常发生在气温较高或者将要下雨(气压低)的时候,这与氧气的溶解能力随着温度的升高和气压的减小而减弱的变化情况是完全一致的。当然,如果水中鱼的密度过大,同样会造成这种现象。对于鱼儿离不开氧,我们可以通过一个小实验来观察、分析并加 We all know that fish can not do without water. However, what I want to tell you is that fish can not leave oxygen even more. Have you seen the phenomenon of fish running to the surface of the water? This phenomenon is often referred to by fish farmers as “fish floating head” (right). Once this phenomenon in the fish pond, it must be oxygen in the water. What happens to water hypoxia? If you look closely, you will find that oxygen in water usually occurs when the temperature is high or it is going to rain (low pressure), which is related to the ability of oxygen to dissolve with temperature The changes that weakened as a result of the increase and the reduction of barometric pressure are completely consistent. Of course, if the density of fish in the water is too large, the same can cause this phenomenon. For fish can not do without oxygen, we can observe, analyze and add through a small experiment