Soil compaction in areas of maize used for silage with the application of wastewater

ABSTRACT The mechanical resistance of the soil to penetration (RP) was evaluated over two consecutive years in areas where off-season maize is produced for silage. Removal of the aerial part of the maize during the ensiling process leaves the soil exposed and subject to compaction, which may compromise a no-till system (NTS). The aim of this study therefore, was to monitor the RP of a soil under plant cover associated with the application of wastewater from pig farming (WPF) in areas of maize ensiling under NTS. The study was conducted in Matelândia, in the State of Paraná, employing seven management systems: soybean/silage/oats and turnip (SSOT); soybean/oats and turnip (SOT); soybean/silage/scarification + oats and turnip (SSSOT); soybean/silage and brachiaria (SSB); soybean/silage/oats (SSO); soybean and silage (SS) and soybean and maize (SM), repeated over two consecutive years. In the treatments that included WPF, 100 m3 ha-1 yr-1 were applied, split into two equal doses: one on the maize and the other on the cover crops. The experimental design was of randomised complete blocks (RCB), with four replications per treatment, and four samples per replication. The system with no cover crops had a higher RP; the 0.10 to 0.15 m layer of soil had the highest RP; whereas the application of WPF at a dose of 100 m3 ha-1 yr-1 decreased the RP.