This Planet is Alive —Weathering and Biology, A Multi-Facetted Problem —

Abstract

The age of planet Earth is about 4.5 to 5.0 ga. Life established itself above, at and below the planet surface about 3.8 ga ago. Weathering processes, although they may take place also on planets without life, are controlled at and under the surface of Earth by biological processes. These include direct mechanical and chemical, and indirect action of the metabolic products of organisms. The organisation and reorganisation of the material of the crust and portions of the mantle are ruled by kinetics of a biological nature. These include the amount and kind of minerals and rocks destroyed and formed, and the accumulation of minerals at specific places. Furthermore the speed of chemical reactions and physical activities is controlled by biological parameters and processes. Some examples and principles of biological weathering and transport are described with emphasis on the interaction of the biotic and abiotic world. Life can be regarded as a chemical process and almost no chemical process on Earth takes place without being a part of Life. Life catalyses the rates of physical-chemical processes and in some cases runs chemical reactions which are thermodynamically improbable. Life and chemistry combine into material transfer activities, which create the geological history of the planet. These transfer reactions have been in co-existance for at least 3 ga. The chemical state of the Earth and its buffering margins are set and controlled by Life.