We explain what the biosphere is, its history, components and layers. Also, what are Unesco Biosphere Reserves.
What is the biosphere?
The biosphere or biosphere is the “living envelope” of planet Earth, that is, the total set of life forms (animal, plant, microbial, etc.) and the system they make up with their respective environments, located in the superficial portion of the earth's crust. In other words, the biosphere is the global ecosystem, which includes all local ecosystems.
The biosphere emerged on our planet around 3.5 billion years ago and since then it has evolved in complexity and biodiversity, despite having gone through numerous mass extinctions. The human being is part of it, and therefore also its communities, nations and cities.
The term biosphere was coined by the Austrian geologist Eduard Suess (1831-1914), but it began to be used formally in scientific studies in 1920, thanks to the Russian scientist Vladimir Vernadski (1863-1945), even prior to the term ecosystemappeared in 1935.
Biosphere is today a term commonly used in the areas of astronomy, geology, climatology, paleogeography and other similar disciplines, always referring to life on Earth.
Components of the biosphere
On the one hand, the biosphere It is composed of life forms in themselves, that is, for the total number of human beings, animals, plants, fungi, microorganisms and others. Besides, It is also made up of the different biogeochemical cycles that make it possible to sustain life which take place on the Earth's surface.
This is because the biosphere is not a passive stratum in which living beings live and that's it. On the contrary, It is a vast network of chemical exchange with the environment at different levels of organization and complexity.
Layers of the biosphere
The biosphere does not have layers since it is not something that has a structure in itself. However, Three systems converge in it that could be understood as fundamental for its maintenance, which are:
- Geosphere The physical, solid layer of the Earth, on whose surface life occurs.
- Hydrosphere The set of all bodies of liquid and solid water that exist on the planet, and without which life would not have been and would not be possible.
- Atmosphere The heterogeneous ball of gases that covers the geosphere, and that provides the gases essential for life as we know it, particularly carbon dioxide (CO2) necessary for photosynthesis and oxygen (O) necessary for respiration.
Importance of the biosphere
The biosphere It is unique in the Solar System since Earth is the only planet on which life has been known. This perhaps means that the location and properties of the Earth are unique or extremely rare, and therefore the emergence of the biosphere is something of supreme importance.
Besides, The biochemical processes undertaken by different forms of life alter the environment adding or subtracting elements in various compounds, which in turn affects the geochemical state of the world.
For example, the emergence of photosynthesis during the Precambrian period had a huge impact on the composition of the atmosphere, filling it with oxygen and reducing carbon dioxide, which allowed the gradual cooling of the planet, by reducing the greenhouse effect of heavy atmospheric gases.
Biosphere and ecosphere
The terms biosphere and ecosphere are synonyms and are usually used interchangeably.
Biosphere reserves
Certain areas are called biosphere reserves. regions of the planet that are considered representative of diverse habitats. Given their great scientific interest and their enormous contribution to biodiversity, they have special support from UNESCO, within the framework of the Program on Human Beings and the Biosphere inaugurated in 1971.
These “reserves” are not protected areas nor are they contemplated in any international treaty. They are part of the territorial sovereignty of their respective countries, but at the same time are part of a global network of spaces sponsored by UNESCO given its interest in ecologically sustainable development.
Nowadays there are 701 biosphere reserves in 124 different countries.
Continue with: Ecology
References
- “Biosphere” on Wikipedia.
- “Biosphere” in the CCH Academic Portal of the National Autonomous University of Mexico (UNAM).
- “What is the biosphere” (video) in UnProfesor.
- “Biosphere” in National Geographic.
- “Biosphere” in The Encyclopaedia Britannica.
