The biosphere is the broadest level of ecological study, the global sum of all ecosystems. From the broadest biophysiological point of view, the biosphere is the global ecological system integrating all living beings and their relationships, including their interaction with the elements of the lithosphere, hydrosphere, and atmosphere. This biosphere is postulated to have evolved, beginning through a process of biogenesis or biopoesis, at least some 3.5 billion years ago.

The term "biosphere" was coined by geologist Eduard Suess in 1875, which he defined as: the place on earth's surface where life dwells.

Biosphere 2 is a 3.14-acre (12,700 m2) structure originally built to be an artificial closed ecological system in Oracle, Arizona (USA) by Space Biosphere Ventures, a company whose principal officers were John Polk Allen and Margret Augustine. Constructed between 1987 and 1991, it was used to explore the complex web of interactions within life systems. It also explored the possible use of closed biospheres in space colonization, and allowed the study and manipulation of a biosphere without harming Earth's. The name comes from the idea that it is modeled on the first biosphere, which is the life system on Earth. The funding for the project came primarily from Edward Bass' company, Decisions Investment, and cost $200 million from 1985 to 2007.

For More Information:
Biosphere K-12 Experiments & Background Information
Biosphere 2

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