The term biosphere was first used by a geologist named Eduard Suess in 1875. He defined biosphere as “the place on earth's surface where life dwells". Vladimir I. Vernadsky refined the definition in 1926, placing the biosphere concept in its current position as one of the spheres in Earth Systems Science. The biosphere is the life zone of the Earth and includes all living organisms: the trees in the park, the birds in the air, fish in the rivers and oceans, the fly on your wall, the viruses that make you sick, bacteria in the trash can, mold on the bread, your pets, and even you and all your friends. The biosphere also includes all organic matter that has not yet decomposed (rotted). The biosphere is interconnected in the other Earth system spheres (Atmosphere, Lithosphere, and Hydrosphere)
Biosphere.
By volume, most of Earth’s biosphere is cold and marine, with 90% of the ocean’s waters at 5°C or colder. Fully 20% of Earth’s surface environment is frozen, including permanently frozen soil(permafrost), terrestrial ice sheets (glacial ice), polar sea ice, and snow cover.
The biosphere has evolved since the first single-celled organisms originated 3.5 billion years ago under atmospheric conditions resembling those of our neighboring planets Mars and Venus, which have atmospheres composed primarily of carbon dioxide. Billions of years of primary production by plants released oxygen from this carbon dioxide and deposited the carbon in sediments, eventually producing the oxygen-rich atmosphere we know today. Free oxygen, both for breathing (O2, respiration) and in the stratospheric ozone (O3) that protects us from harmful UV radiation, has made possible life as we know it while transforming the chemistry of earth systems forever.
The biosphere is a core concept within Biology and Ecology, where it serves as the highest level of biological organization, which begins with parts of cells and proceed to populations, species, ecoregions, biomes and finally, the biosphere. Global patterns of biodiversity within the biosphere are described using biomes.
Biosphere I's total surface area is about 197,000,000 square miles. Approximately 75% of of this is covered in water. The other 25% is divided primarily into seven major land masses or continents. On each of these continents exists the various necessities of life, including air, water, soil, and food. However, the ecosystems that are able to survive and produce on each continent vary widely.
The Earth is a complex balance of her ecosystems. It is the first biosphere, and thus obviouly the model for Biosphere II. Earth contains six ecosystems, including marshes, farmland, savannahs, deserts, oceans, and rainforests. Biosphere I contains countless different plant and animal species, as well as a wealth of minerals and fossil fuels. The basis of life within the Biosphere is mutation and natural selection as forms of self-preservation.
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