Abstract

The physical fertility of the soil is based on maintaining a state of lumpy and biodynamic aggregation (the biostructure), which is closely associated with clay and its type, the existence of iron and aluminum, alkaline earth cations, and fundamental to the presence of organic matter, microorganisms and other living organisms; where the best soil aptitude can be expressed to make potentially available nutrients available to plants. The physical fertility of the soil is not only physical but also physical - chemical and biological and is decided in the way in which the colloids joined to the other factors are integrated for the formation of a porous and stable bio - structure. When talking about physical fertility, the art of reaching a certain soil productivity and its maintenance is exposed. The management of the physical environment in the tropical soil. It is known that the productivity of soils decreases with the years of crops, and this reduction occurs faster in sandy soils in equatorial climate and slower in clay soils in subtropical climate but it always occurs and will occur while they are being used, the current techniques of preparation and cultivation of the soil. The factor that is entering the "minimum" is the active structure of the soil, due to suffering pronounced compaction. The limiting factors of production in tropical soils are oxygen deficiency in soil air, water depletion and limited root development. 40% of the terrestrial globe is tropical zone, but only 10% of this area is solid ground, even so the 45 million km2 of land of the tropics complete 30% of the land of our entire planet. However, only 10% of the world's population lives here starving because they can not produce enough for their sustenance. In all the tropical zones of the world new ways are being looked for to prepare the soils, since it was confirmed that it is not the warm climate what prevents an adequate production of the earth, but the wrong handling of its soils. physical fertility, organic matter, bio-structure, organic agriculture Physical Fertility of Soil and Organic Agriculture in the Tropics