Effect of Continued Cultivation on Some Properties of Lixiviated Red Ferralitic Soils/Efecto del cultivo continuado en algunas propiedades de los suelos Ferraliticos Rojos Lixiviados

Mechanical actions exerted by diverse categories of machines are used to take the soil to the most desirable physical state. The mechanical operations are carried out in the soil with or without the plant and on the plant for harvesting with high yields. All these actions can affect the soil micro structure, its density and content of organic matter, as well as its capacity of cation exchange, its fertility and productivity. To value the behavior of these properties, Lixiviated Red Ferrallitic soils were studied in areas without cultivating, cultivated with sugar cane (Saccharum officinarum L.) during twelve and seventy-five years, cultivated with medicinal plants for twenty years and cultivated with varied crops for eighteen years, with irrigation. It was found that the pH ([H.sub.2]O and KC1) and the hydrolytic acidity increased as years of sugar cane cultivation increased, which did not happen in the areas without cultivating and in soils dedicated to medicinal plants. In the Red Ferrallitic Lixiviated fields with several cultivations and irrigation, the pH reached values above seven due to the high content of calcium in irrigation waters derived from karst region, effect generated by the climate change.