Efeito do uso do solo nos atributos físicos e químicos nos lotes do Perímetro Irrigado Piauí, município de Lagarto-SE

Abstract

Irrigated perimeters are of great importance for Northeast region of Brazil due to adverse climate and social-economic conditions. In that region predominate small farms that serve both as subsistence agriculture and as small suppliers for urban population. The expansion of urban areas increases the demand for food and other supplies, putting pressure on both agricultural activities and the use of environmental resources such as water, soil, and vegetation. The system reacts by increasing the technological levels. This research aimed to evaluate some of the most important soil physical and chemical attributes in soils submitted to different land uses (passion fruit (Passiflora edulis sims) cultivation; pepper (Capsicum frutensens L) cultivation; passion fruit and pepper consortium; and grazing pasture of Brachiaria decumbens, in the Piauí irrigated perimeter, Lagarto county-SE. Except for the pasture area, land uses in the perimeter showed relative estate of soil physical conservation, enabling the soils to function as a good environment for root growth and water storage and supply to plants. Soil total porosity is higher than other surface sandy soils of the same type. Land use for pasture decreased soil macroporosity at near critical levels for aeration and root development. Soil fertility was enhanced in soils cultivated with pepper and pepper and passion fruit consortium. PST values were low enough to present risk of soil salinization. One important finding was that P levels were excessively high under all soil uses but pasture, showing that there must be mismanagement in fertilizer application.