Utilização de água residuária tratada na recuperação da fertilidade de solo degradado no semiárido paraibano

This study aimed to evaluate the effect of treated wastewater application on soil organic matter and phosphorus recovery in an Anthroposol in the semiarid region. An experiment was carried out with irrigation of five caatinga forest species, in which three treatments were applied that consisted of the variation of water type and volume applied to the soil, 7 L per week of water supply, 7 L and 14 L per week of wastewater. After two years of irrigation, soil samples were taken and analyzed for soil organic matter and phosphorus. The organic matter content in the treatment with 14 L application of wastewater was five times higher in relation to the application of supply water in the superficial layer and eight times in the sub-surface, respectively. Based on the results found, we can say that the use of wastewater from treated domestic sewage can be considered an alternative for the recovery of the productive capacity of the soil by the increase in the organic matter and soil phosphorus contents. Irrigation with treated wastewater can provide a considerable increase in soil organic matter and phosphorus content up to 30 cm deep.