The term "biosphere" was for the first time introduced by the famous biologist Lamarck at the beginning of the 19th century. It characterizes Earth cover occupied with living organisms (people, animals, plants, microorganisms) which is exposed to their influence in the most various forms. The biosphere occupies the top part of a lithosphere, the lower part of the atmosphere and all hydrosphere. The complete doctrine was created by our compatriot Vernadsky in the first half of the 20th century. Why the biosphere is called an ecological system?
First of all, remember what is ecology. According to the standard definition, it is the science studying the relations of living organisms and their communities among themselves and with the environment. As the concept of the biosphere includes existence of living organisms, is obvious that the biosphere has a direct bearing most on ecology. Now remember what is a system. It (in broad interpretation of a word) - a set of elements which are in indissoluble communication with each other influence at each other, forming a certain integrity, unity. Figuratively speaking the system can be compared to some difficult mechanism consisting of a set of details, big and small, simple and difficult. Uninterrupted activity of all mechanism in general depends on excellent job of each detail. It is easily possible to see that the biosphere completely satisfies to both definitions. Everywhere on our planet – both on the land, and in water, and in air - living organisms, simple and difficult meet. Even in century ices of Antarctica, even in the deepest ocean hollows there is life. Separate organisms form simple forms – populations. Populations, in turn, form more complex communities – biocenoses. Everything is in indissoluble communication, everything depends from each other. Well, and biocenoses, in total with lifeless factors of the environment, form ecosystems. One ecosystem can be unlike another, but they are again closely interconnected and depend from each other, exchanging substances and energy. Here and there is an eternal circulation. Therefore the biosphere can be considered an ecosystem rightfully. Review a concrete example. To which of you it was not necessary, having slammed the stuck mosquito, to wish in a fit of temper: "That all of you were gone!"? And what will be if really mosquitoes suddenly disappear? It is the main food of frogs, thus, after blood-sicking creatures the livestock of Amphibia will sharply be reduced. Dragons eat frogs – which, in turn, exterminate the mass of mean rodents. You see to what consequences could lead your careless wish if it suddenly came true. When the mechanism is fixed, disappearance even of the tiniest detail can put it out of action.