Carbon increase and soil physical improvement in an onion no-tillage system

Abstract

The no-tillage vegetable planting system (NTVPS) is a way to integrate production and soil conservation. The study was conducted on a Haplic Cambisol in the municipality of Alfredo Wagner -SC, in 2017. It aimed to evaluate physical attributes and carbon fractions of soil under consolidated NTVPS cultivation for 10 years as compared to thirty-year conventional tillage (CT) and a native forest (NF) on a Haplic Cambisol. The aspects evaluated were: total organic C, soil density (SD), total porosity (TP), macropores, micropores, aggregate stability, resistance to mechanical penetration (PR) and water infiltration into de soil. CT showed higher SD as compared to NTVPS, mainly in the 5 to 10-cm layer, whereas PR was higher in NTVPS, particularly in the 5 to 10-cm layer, thus exceeding the critical limit for this variable. Nevertheless, NTVPS showed greater accumulated water infiltration and infiltration stabilization at 20 minutes. In the native forest, infiltration was lower than that in NTVPS, and the lowest constant infiltration values occurred in CT from the beginning of the test. The NTVPS treatment showed greater efficiency in carbon storage and aggregation as compared to CT, therefore, favorable structural conditions for plant growth.