Indicadores da qualidade do solo em Sistemas Agrícolas anuais e perenes na Chapada do Apodi - CE.

Abstract

This work had the proposed to evaluate the alterations in the microbial activities, chemistry and physics in soil under annual and perennial agricultural systems in the area of the Chapada do Apodi - CE. It tried to test the hypothesis that the agricultural use of areas under annual and perennial systems causes environmental alterations that they influence the biomass and the microbial activity of the soil, reducing it in relation to areas under natural vegetation. Two areas were selected with respective witness (natural vegetation); the first under cultivation of banana trees (Fazenda Frutacor) and the other under cultivation of rotation corn and soy (Fazenda Faedo). Samples composed of soil were collected in three depths (0-5, 5-15 and 15-25 cm) with four repetitions. In the collected samples physical analyses, chemistries and microbiological were accomplished. Physically, an elevation was observed in the clay text, with the increase of the depth in the area cultivated with banana and in the forest natural pivot. In relation to the chemical attributes of the soil, the potential risks of salinity and of saturation for sodium seemingly are worthless. The handling practices reduced N and the total organic carbon in the soils of the areas under cultivation. With relationship to the microbiology of the soils, the carbon of the microbial biomass and the population of arbuscular mycorrhizal fungi were more elevated in the depth of 0-5cm of the soil. The basal breathing of the soil identified that the soils of the appraised areas have microbial when compared low activity the soils of the Cerrado. The activity and production of the arylsulphatase and of the acid phosphatase were stimulated possibly, for the competition of the anions H2PO4- and SO4- for the same ranches of adsorption in the coloides of the soil, in the banana areas and rotation corn and soy. The largest activity of the enzyme β-glucosidase happened in the cultivated areas, influenced by the amount and quality of the vegetable residue come back to the soil.