Are the microorganisms contained in activated sludge the same as those in the river?

Activated sludge microorganisms are also found in rivers and lakes, and there are no microorganisms specific to activated sludge.
For example, tsuriga beetles, amoebas, and worms are found in activated sludge, rivers and lakes.

However, because microorganisms that can withstand sewage pollution dominates, the type composition and population of the entire microorganisms (this is called microbiota) are different from the natural world.
Since the environment of the reaction tank is special, it is rare that a microbiota such as activated sludge naturally exists.