There are two types of ecosystems such as natural and artificial. So Natural ecosystems are those that prevail in nature like pond stream, river, Lake Sea, ocean, forest, grass land. They have a common gross structure and function. All natural ecosystems are open systems where there is free exchange of inputs and outputs with other systems. Natural ecosystems are of two types such as – (i) Terrestrial and (ii) aquatic:
(i) Terrestrial ecosystem:
There are several varieties in terrestrial ecosystems without any precise boundaries between them. The terrestrial ecosystem is further divided into-
(a) Forest ecosystem,
(b) Grass land ecosystem,
(c) Direct ecosystem,
(d) Man-engineered ecosystem.
(ii) Aquatic ecosystem:
The aquatic ecosystem is further, divided into (a) fresh water ecosystem and (b) marine ecosystem.
Ecosystems are also typed as complete or incomplete. Complete ecosystems must have four basic components such as the produces, consumers, decomposers and the basic components.