We can think of the natural world as divided into a variety of households, each containing a number of living things as well as non-living things, such as soil, water, air, and a variety of chemical elements. This is much like domestic households that contain both people and the things necessary to support their lives. Each natural household is known as an ecosystem , a term that reflects the many activities and interactions that regularly take place between its living members and the chemical and physical features of their environment.
Ecosystems can be as small as a rotting log or as large as an ocean.
The Amazon rain forest is an ecosystem, as is Antarctica. It is often convenient to identify small ecosystems that exist within larger ecosystems, such as an ocean tide pool or a forest glade. The Chesapeake Bay is certainly an ecosystem. Accordingly, an understanding of the Bay involves a close look at the biology of the Bay's 2,700 species of living things, its geological characteristics, chemical components, and their patterns of interactions. Because we are also a significant part of the Bay ecosystem, our role must also be taken into consideration if we are to gain a complete understanding of the Bay's ecology.