出典:Wikipedia
出典:『Wikipedia』 (2011/07/12 20:23 UTC 版)
Freshwater fish are fish that spend some or all of their lives in freshwater, such as rivers and lakes, with a salinity of less than 0.05%. These environments differ from marine conditions in many ways, the most obvious being the difference in levels of salinity. To survive fresh water, the fish need a range of physiological adaptations in order to keep the ion concentration of their bodies balanced.