An ecosystem (or ecological system) is a large community of living organisms (plants, animals and microbes) in a particular area.[2] The living and physical components are linked together through nutrient cycles and energy flows.[3] Ecosystems are of any size, but usually they are in specific places.
Each ecosystem has its own community. An aquarium community, for example, can have small fish and other organisms. A desert community may have cacti, small snakes, and scorpions. A pond community can have frogs, insects, snakes, and plants, and a forest community may have rabbits, foxes and pine trees. The species in a community are divided into populations according to the particular habitats and ecological niches in the ecosystem.