The objective of this work was to analyze the changes in the chemical attributes of an Ultisol irrigated with different dairy effluent dilutions. The experiment was set up using a randomized block design with five dilutions of dairy effluent (DE) in public water supply (PWS) (T1 - only PWS, T2 - 10% of DE plus PWS, T3 - 20% of DE plus PWS, T4 - 30% of DE plus PWS, and T5 - 40% of DE plus PWS). Soil samples were collected at five depths to quantify the attributes of pH, organic matter (OM), potassium (K), phosphorus (P) and electrical conductivity of the soil saturation extract (ECss). No significant effects of dairy effluent dilutions were found in altering the pH, OM and K+ values of the Ultisol after 240 days of application. However, there was a significant increase of P in T4, and of ECss mainly in the 0.10 to 0.20 m layer of T5.
