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1.2 Limits of the biosphere
The biosphere is an organized, defined shell of the crust, coupled with life. The limits of the biosphere are primarily due to the field of existence of life. From these definitions there are several very specific concepts that reveal the essence of the biosphere.
1. The biosphere is not just one of the existing envelopes of the Earth, like the lithosphere, hydrosphere, atmosphere. IN AND. Vernadsky very concisely indicates its main difference - it is an organized shell. And in order to understand the essence of the biosphere, it is necessary to understand how and by whom it is organized, what is the organization of the biosphere.
2. The biosphere has certain limits; that is, some finite dimensions within which it can be selected and scientifically studied. Consequently, after identifying the main driving force behind the development of the biosphere — living matter — it is necessary to establish the spatial and temporal limits (limits) that are imposed on the activity of living matter.
3. The limits of the biosphere are associated with the field of existence of the living. But any field can be saved and maintained only if certain physical or chemical parameters, indicators of its state are maintained. This means that some necessary and sufficient parameters must be established for the physical preservation of the "fields of life" in the biosphere and the biosphere itself.
Over a billion years of the biosphere’s existence, organization has been created and maintained by the activity of living matter - the totality of all living organisms. The form of living activity, its biogeochemical work in the biosphere, consists in the implementation of irreversible and open cycles of matter and energy flows between the main structural components of the biosphere integrity: rocks, natural waters, gases, soils, vegetation, animals, microorganisms. This uninterrupted cyclical process is one of the cornerstones of the biosphere theory and is called biochemical cyclicity. The study of biochemical cycles as open cycles helps to penetrate more deeply into the essence of the processes of organization of the biosphere shell. Each subsequent state of the biosphere does not repeat the previous one. Involvement in migration cycles leads to continuous renewal of the biosphere, contributes to its progressive evolutionary development, complication of living matter, increasing the diversity of living organisms.
The question of the limits of the biosphere V.I. Vernadsky associated with the preservation of the limits of life. The ideas about them undergo radical changes literally with each new day of the development of science. Yesterday we were convinced that the boiling point of 100 C is impossible for the life of any living creature. Today, all the new discoveries of the world of thermophilic organisms found in volcanic vents, geysers and underwater changes are impressive, for some of them the centigrade temperature is “cold” for normal cell division (reproduction), they also live at +250 С and even at +250 C. There is information about the possibility of bacteria transferring the temperature of absolute zero (-273 C).
The plasticity of life is great, but its limits objectively exist, and they define the limits of the development of the biosphere, its structure and functions. The upper boundary of the biosphere covers the entire troposphere and is limited to the ozone layer (23-25km), which, with a kind of screen, protects all life from the detrimental effects of ultraviolet radiation. The lower boundary is very indented; the biosphere includes the entire hydrosphere of the land and the World Ocean; on the continents it penetrates, on average, into the crust to a depth of 16 km . Here it mates with the region of “former biospheres”, - so V.I. Vernadsky named the preserved remnants of the biosphere of past geological periods. This is the accumulation of limestone, coal, oil shale, residual rocks.
Former biospheres are documented evidence of the geologically eternal development of the biosphere. In the large geological cycle of substance movement, the fossil remains of the biospheres of the past reach the surface of the day, are destroyed, are captured by living organisms in new biogenic cycles of circulation, then again come out of it and descend into the deep horizons of the earth's crust, where they are metamorphosed, melted, and where they are stored they are solar energy. So it lasts for billions of years, as long as the biosphere exists.
The age of the biosphere is approaching the geological age of the Earth as the plans of the solar system.
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