| ABSTRACT: The aim of this work was to present in a didactic way the biogeochemical cycles of the four most important elements and substances on global chemistry: water, carbon, nitrogen and phosphorous. The importance of these elements and substances becomes from the great magnitude of mass and energy utilized in their processes, and on their essentiality on biosphere formation and maintenance. This work intends to showthe interdependence between these great cycles and the biosphere, and the way that the human activity influences on the chemical dynamic of the globe, and the consequences of these shifts for the humanity itself. |
