The Three Categories
There are the main categories of an ecosystem. These three categories are terrestrial, marine, and freshwater. Terrestrial means on land, marine means the oceans and saltwater, and freshwater means all of the freshwater on Earth. Ecosystems can be categorized into these groups based on where they are located and what they contain.
Levels of an Ecosystem
There are a few levels to an ecosystem that help to categorize the types of organisms that live there. From largest to smallest, the first category is the ecosystem itself. An ecosystem is made up of one or more communities and their nonliving environment. The second category is community. Community is basically just made up of all of the populations that live in an area. After that is population. Population means all of the organisms of a species that live together at the same time. And lastly, the simplest level is organism. An organism is any living thing. In order, the levels are organism, population, community, and ecosystem.
An organism's niche, habitat, and ecosystem
Every organism has their own ecosystem, habitat and niche. For example, a bee. A bee's ecosystem is terrestrial, as they live on land. The bee's habitat would be the beehive and it's location. The bee's niche is to pollinate flowers. These are all examples of how every living organism has an important role in the survival of many other things.