Effects of brewery wastewater irrigation on Antofagasta soils

摘要

Saline soils, common to the Antofagasta region of Chile, limit agricultural activity, the use of phytoremediation and the development of energetic crops. The aim of this work was to evaluate the effects of leaching with brewery wastewater and distilled water on the soil profile by using column assays in order to improve the conditions of saline soils by removing salts. Conductivity and pH were measured in leachate samples and in the soil profile. The results showed that the application of distilled water and brewery wastewater had similar effects, although different in their magnitude, on the conductivity and pH in the soil leachates, but caused different behavior in these variables in the soil profile. The pH values in leachate samples increased from 7.5 to 8.5 and from 8.3 to 9.2 when distilled water and brewery wastewater were used. Conductivity decreased from 18 to 3 mS/cm and from 18 and 7 mS/cm when distilled water and brewery wastewater were used. Distilled water maintained the pH around 8.3in the soil profile meanwhile the use of brewery wastewater kept the pH around 7.3. Both irrigation solutions decreasing the conductivity in the soil profile reached values between 0.8 and 2.1 mS/cm. It was possible to decrease the conductivity of the soil profile by using distilled water and brewery wastewater as an irrigation solution, although brewery wastewater had high initial conductivity (4.7 mS/cm). In addition, brewery wastewater enabled the pH to be kept constant (around 7.3) in the soil profile. The result indicated that brewery wastewater may be used in the first stage to improve the quality of the saline soil of the Antofagasta Region.