Alterações na resistência do solo ao longo do tempo em sistemas de preparo e de culturas

Abstract

The different soil tillage have a direct influence on its physical properties, such as soil compaction, which negatively affects crop productivity. Soil resistance to penetration (RP) has been widely used to measure the degree of soil compaction, thus being able to define the critical limit for its development. This study aimed to evaluate soil compaction and reconsolidation under no-tillage system with chiselling and cover crops. The experiment was conducted in the experimental area of the Federal Technological University of Paraná, Campus Dois Vizinhos, the experiment was based on five soil preparations that are: no-tillage (PD); annual no-tillage (PDEa); scarified no-tillage with 3-year interval (PDEi); no-tillage under minimum annual tillage (PDPMa) and no-tillage under minimum tillage with a 3-year interval (PDPMi) and four different species of cover plants: black oats (Avena strigosa Schreb), common vetch (Vicia sativa), forage turnip ( Raphanus sativus L.) and the consortium between the three species oats + vetch + turnip. The experimental design used will be that of random blocks, composing a simple factorial of 5X4, with three replications totaling 60 plots of 40 m². RP evaluations were carried out before and after tillage in 2020, cover crops, corn, before and after tillage 2021. Mechanical chiseling has an immediate effect on the reduction of RP in PDEa and PDPMa, but during the planning, it was possible to observe the displacement of the RP curve of these tillage to the right, in the evaluation that precedes the 2021 tillage, there was no statistical significance in any depth evaluated. Cover crops independent of statistical significance in the evaluation prior to tillage in 2020 and 2021, where no year in 2020 there was statistical difference in the layer of 0.15-0.20 and 0.20-0.30 m where the intercropping presented the lowest RP in the first layer and black oat and the lowest intercropping RP in the second layer, respectively, and in the 2021 evaluation in the 0.00-0.05 layer, where the forage radish presented the highest RP value. After 13 months of evaluation, the effects of the soil tillage no longer persisted.