Distinguish between Marine and Fresh water environment.
Fresh water environment : Lakes and ponds are stagnant fresh water bodies and occur particularly in every biome. They vary in size from less than a hectare to hundreds of hectares. The relatively shallow lakes called eutrophic lakes, have a rich accumulation of organic products. The fresh water ponds are called autotrophs and have microscopic phytoplanktons.
Streams and rivers differ in volume, temperature etc. The nature and composition of flora and fauna depend on the source of river and the land environment.