Chemical and physical attributes of an Ultisol under sustainable agricultural production systems

Abstract

This study aimed to evaluate the effect of four production systems: agrosilvopastoral; pasture; agropastoral and notillage, all compared to a native forest area (Cerrado), on the chemical and physical attributes of an Ultisol. Physical and chemical analyzes of the soil were performed, in the layers of 0.00-0.05, 0.05-0.10, 0.10-0.20, 0.20-0.40 and 0.40-1.00 m. Regarding the physical analysis, samples of up to 0.40 m were used. We verified that the soil under the Cerrado biome displayed higher organic matter content, aggregates larger than 2 mm percentage and weighted mean diameter in the layer of 0.05-0.10 m. The pasture system showed higher pH and soil base saturation, and higher Ca and Mg contents in the 0.10-0.20 and 0.40-1.00 m layers. All systems provided an increase in soil organic matter content. The highest contents of P, K, Ca and Mg were observed in the surface layer for all systems. Agropastoral system disaggregated the soil in the 0.05-0.10 m layer. No-tillage resulted in similar soil porosity values along the soil profile. Urochloa brizantha cv. Marandu usage as pasture contributed to improving soil chemical and physical fertility.