Finally, after the lake or pond began to fill up, the hired plants began to grow. As all the plants died, they turned to sediments and washed the basin (platform) and began to rise at the bottom of the lake. The water is very shallow, and finally the water that grows out is full and disappears completely. This may also happen in wetlands, because wetlands are very shallow. Finally, a lot of water grew on the bush.

In the 1960s and 1970s, the case of Lake Erie was the most nutritious propaganda. One is called "Dead Lake". The smallest river passes through the Great Lakes from a shallow place. After decades of development and high development of nutrients, it has flooded the land of agriculture and cities. As a result, plants and algae suffocate in lakes of most other species, and the smell of leaving the beach is unnecessary because rotten algae flock to the coast. The new pollution control of sewage treatment plants and agricultural methods in the United States and Canada has greatly reduced the amount of nutrients entering Taihu Lake. Forty years later, although there are no completely free pollutants and nutrients, Lake Erie is a thriving lake.