Lentic Ecosystems
Lakes are inland, depressions containing standing water. They vary considerably in area and depth. The largest lake in the world, the lake Superior in North America has a surface area of 83,000 km2 and a maximum depth of 307 metres (5,000 feet). Whereas the deepest Cake, in the world, lake Baikal in Siberia is nearly half the area of Lake Superior, i.e., 31,500 km2. It has, however, more than twice its depth (706 metres). Fresh water lakes of this earth hold 125 x 103 Km3 of water and have inflow as well as outflow.
In addition they have various patterns of circulation within their boundaries and so their water is not totally static. However, they do lack the constant linear or turbulent flow of the rivers.