An ecosystem is collectively an area where animals, plants and other organisms, also the landscape and weather, work together to form a life. Ecosystem embodies biotic (living) and abiotic (non-living) factors.
Each factor of the ecosystem is related to the other one, either directly or indirectly. For instance, change in temperature will have an effect on plants growth. Animals who are dependent on plants as their food & shelter will have to adapt according to the change. The size of ecosystems vary – for instance the tide pools, when the small ponds are left behind when the tides are washed out, forms a small ecosystem. Such ponds contain seaweed (algae) which develops food by photosynthesis. The herbivore specie in such pond eat seaweed as food. Whereas, carnivores in the same pond rely on other animals for food.
The ecosystem prevailing on Earth is actually a series of interlinked ecosystems. Ecosystems are connected to make biome – large area of sea, land or atmosphere, such as ponds, forests, tundra, reefs, etc. Biomes are connected with each other depending upon the habitats and specie living in them. Within each biome, you may find several ecosystem. It should always be kept in mind that disturbing a single element in an ecosystem will have an effect on the other element, which in turn will cause the whole ecosystem to change and eventually disturbing whole biome.