Biochar After Thirteen Years of Agricultural Crops on the Physical Attributes and Organic Carbon of a Yellow Oxisol in Central Amazon

Abstract

Biochar has been identified as a conditioner for the physical, chemical and biological properties of the soil. In this perspective, it is reckoned that when added in the long term, this material may condition improvements in the physical properties of agricultural soils. As a result, the objective of this work was to quantify changes in the physical attributes of the soil after thirteen years of the addition of biochar in a Yellow Dystrophic Oxisol in Central Amazon, in the agricultural ecosystem in Brazil. In a thirteen-year experiment (2006-2019) with rotation of agricultural crops, the physical properties of a clayey Yellow Oxisol with the addition of increasing doses of biochar, were studied. The experiment was conducted in randomized blocks, with four replications and four treatments, making up sixteen experimental units with a size of 10 m × 10 m (100 m2). The analysis of the results did not indicate a positive effect on most of the physical attributes studied, however, there was significance only for two sets of data. Compared to soil without biochar, there was a decrease in the density of soil particles, and an increase in soil resistance to penetration into the surface layer, in soil with biochar. No difference was found in the subsurface layer for all evaluated attributes.