Indicators of soil quality in rotation system at the Plateau of Apodi - CE

Abstract

This work evaluated the changes in the number of spores of arbuscular mycorrhizal fungi (AMF) and enzymatic activity, in soil under system of rotation maize and soy, in the Plated of Apodi, Limoeiro of Norte-CE. The hypothesis was tested that the agricultural use, cause environmental alterations that reduce the presence of population of arbuscular mycorrhizal fungi and the microbial activity, in relation to the natural vegetation. An area under rotation culture was selected maize and soy and its control. Soil samples were collected in 3 depths (0 to 5; 5 to 15 and 15 to 25 cm). Physical, chemical and microbiological analyses were accomplished. An elevation was observed in the clay text, with the increase of the depth in the area of natural vegetation. The potential risks of salinity and of saturation for sodium, seemingly, they are worthless. The handling practices reduced the nitrogen and the total organic carbon in the soil of the area under cultivation. The population of arbuscular mycorrhizal fungi was more elevated in the depth of 0 to 5cm of the soil.  The activity and production of the arylsulphatase and of the acid phosphatase were stimulated for the competition of the anions H₂PO₄^- and SO₄^- for the same ranches of adsorption in the coloides of the soil, in the area of rotation maize and soy. The largest activity of the enzyme b-glucosidase happened in the cultivated area, influenced by the amount and quality of the vegetable residue come back to the soil.