So... What is an ecosystem?

There are many terms that have to be defined before stating what an ecosystem is. A particular group of organisms that are capable of interbreeding is known as species, and form a population when they live together. Several populations living in a single area are known as a community. Then, an ecosystem appears when this community interacts with the physical environment of matter and energy in which they live. Organisms are the biotic factors and non-living objects and conditions are the abiotic factors that make up the ecosystem. Several ecosystems with similar climatic characteristics and populations are known as biomes.

Here I show some examples of ecosystems:

Tropical rain forest

This is one of the most productive ecosystems because of its warm temperatures and high amount of precipitation (abiotic factors). Tall trees have enough resources to grow there, as well as populations of bushes. Animals include monkeys, elephants, snakes and insects.

Tundra

As opposed to the tropical rain forest, the tundra is the least productive ecosystem because of its low amount of precipitation and harsh cold temperatures. The plant populations limit to moss and lichens, which can endure the freezing conditions. Animals are highly adapted as well and include polar bears, caribou, and some ducks and geese.

Coral reef

Coral reefs are a type of marine ecosystem and contain an enormous diversity of organism ranging from corals to anemones to sponges to several species of fish.

Urban ecosystem

These are artificial ecosystems created and populated by humans. We share these environments with many other species of plants and animals. As an example, New York City, which can be considered one of the world's most urbanized areas, incorporates Central Park in which there is a higher concentration of other populations. All urban ecosystems are shared between us and other species.

These are just a few examples of strikingly different ecosystems. Around the globe there are many similar ecosystems (which I previously defined as biomes) but it's best to know that every single ecosystem has its own mix of biotic and abiotic factors that make it unique.