An ecosystem is a community of living organisms such as microbes, plants, and animals and non-living abiotic components such as sunlight, water, air, minerals.
There are aquatic ecosystems such as wetlands, lakes, coral reefs, hydrothermal vents, and others.
There are also terrestrial ecosystems such as deserts, savannas, tundras, mountains and the forested ecosystems such as tropical evergreen, tropical deciduous, boreal, and others.
Humans have even created their own, new ecosystem, the urban ecosystem.
Check out this resource for a more complete listing of ecosystem types.