A broader meaning of biosphere is all of the living organisms and their environment.
The actual thickness of the biosphere on earth is hard to measure.
The biosphere works in concert with these other major earth systems (Knight and Schlager 2002).
Margulis and Sagan (2002) define biosphere as "the place where life exists," and Mayhew (2004) as "the zone where life is found."
Biosphere is historically and most commonly defined as that part of the Earth in which living organisms exist.
Biosphere is an interdisciplinary concept for integrating astronomy, geophysics, meteorology, biogeography, evolution, geology, geochemistry, hydrology and, generally speaking, all life and earth sciences.
When the word Biosphere is followed by a number, it is usually referring to a specific system.
Viewed as limited to only the living organisms, the biosphere occupies about 0.00008 percent of the mass of the earth (Knight and Schlager 2002).
Microscopic organisms live at such extremes that, taking them into consideration puts the thickness of the biosphere much greater.
The biosphere's ecological context comes from the 1920s, preceding the 1935 introduction of the term "ecosystem" by Sir Arthur Tansley.
The term "biosphere" was coined by geologist Eduard Suess in 1875.
Another concept of the biosphere is as simply "life on earth," in other words, the total of all living things on earth (Knight and Schlager 2002).
Some life scientists and earth scientists use biosphere in the sense of "life on earth"; that is, the total sum of living organisms (the "biomass" or "biota" as referred to by biologists and ecologists).
The concept that the biosphere is itself a living organism, either actually or metaphorically, is known as the Gaia hypothesis.
Soviet mineralogist and geochemist Vladimir Vernadsky (1863 - 1945) defined ecology as the science of the biosphere.
The biosphere mass, which they consider only the living organisms, accounts for only 0.00008 percent of these four systems.
James Lovelock, an atmospheric scientist from the United Kingdom, proposed the Gaia hypothesis to explain how biotic and abiotic factors interact in the biosphere.
Our biosphere is divided into a number of biomes, inhabited by broadly similar flora and fauna.