MONITORING OF ELECTRICAL CONDUCTIVITY OF SOIL SOLUTION UNDER DIFFERENT DOSES OF APPLICATION OF STILLAGE - DOI: 10.13083/1414-3984/reveng.v23n6p552-561

Abstract

The objective of this study was to evaluate the electrical conductivity (EC) and pH of soil solution cultivated with Vitória pineapple and fertilized with stillage to supply 0, 50, 75, 100 and 125% of the potassium recommendation for this culture, obtaining treatments: T1 – 0 m³ ha-¹; T2 – 231 m³ ha-¹; T3 – 347 m³ ha-¹; T4 – 462 m³ ha-¹; T5 – 578 m³ ha-¹. The experiment was conducted in a greenhouse at the Department of Biosystems Engineering ESALQ/USP. The planting was conducted in trenches open at ground level fully lined with canvas and filled with soil classified as Oxisol. The application of stillage were performed fortnightly through fertigation system using drip irrigation. Extractors were installed at depths of 0,20 m and 0,40 m for extraction of the solution, vacuum was applied at the tension of 60kKPa two hours after the fertigation. The solution was collected 30, 120, 210 e 270 days after starts of treatments. It was found that treatments with stillage application showed the highest EC in the soil surface layers. The pH, otherwise, decrease with the increment on the vinasse levels.