Chemical characteristics of a saline-sodic soil leached with water depth parceled

Abstract

In saline-sodic soils, even with gypsum appliance, immediate leaching of salts can promote the dispersion of clay and the impermeability of the soil, hindering soil recovery. The objective of this work was to evaluate the influence of the parceled leaching on diverse chemical characteristics of a saturated soil paste extract, in saline-sodic soil samples. Columns of PVC were filled with samples of soils Fluvent of Ipanguaçu, RN, Fluvent of Caicó, RN and Vertisol (V) of Mossoró, RN, Brazil. The management consisted in applying leaching solution, with CaCl₂ and MgCl₂, with the total volume and parceled in two, four and six times, with intervals of 22 days among appliances. In the saturated soil paste extract, the electrical conductivity, pH and concentration of sodium, calcium, magnesium and sulfates were determined. The pH and cations exchangeable were determined in the soil. The application of gypsum and water depth reduce the exchangeable sodium percentage and the electrical conductivity of saturated soil paste extract to values lower that 15% and 4 dS m^-1, respectively, mainly when the water depth is applied in parcel.