Accumulation and percolation of phosphorus in the soil due to the application of wastewater from swine farming in maize culture (Zea mays L.)

The swine culture is considered by environmental agencies as an activity potentially causing environmental degradation. In recent years, in the western region of Parana, has increased the use of wastewater from pig farming (ARS) in fertigation of crops, which improves soil conditions due to the supply of nutrients, in addition to cost savings associated with fertilizer and water. One of the elements of the ARS is the phosphorus which, when in excess, can compromise the quality of the environment, as a contaminant of water. This study aimed to evaluate the best blade of ARS, used for fertigation, which cause less contamination by phosphorus, of the percolating soil and water to the groundwater. We evaluated five blades of ARS (0, 112.5, 225, 337.5 and 450 m(3) ha(-1) per cycle), combined with two fertilization of soil (50 and 75%) in Latossolo Vermelho distroferrico cultivated with maize. It was observed that the higher blades of ARS show greater accumulation of phosphorus in the soil. For the percolate, the indices of phosphorus found do not present risk of contamination to the water.