What is an Ecosystem?

Ecosystems are the sum of all the interactions between biotic, living, and abiotic, nonliving, factors in the environment. They fall into one of two general categories either terrestrial or aquatic.

The major types of ecosystems are known as biomes. Terrestrial biomes such as deserts, rainforests, and tundra are categorized by two major factors annual rainfall and temperature.

Of the aquatic biomes the freshwater are the rarest as lakes, rivers, streams, and springs make up less than two percent of the earth's surface. Even so these ecosystems are comprised of a large diversity of animals and plants.

Ocean biomes which make up 75 percent of the earth's surface include the shallows, open ocean surface, and deep ocean. The shallows support the largest part of the ocean's diversity and coral reef ecosystems. The surface of the open ocean supports many of the earth's photosynthetic organisms and even the deep ocean contains a number of organisms although light is unable to penetrate.