Enhancing soil physical quality and cotton yields through diversification of agricultural practices in central Brazil

Abstract

AbstractBrazil plays an important role in the global agricultural production, making Brazilian productive land use and management a critical issue. This study tested the hypothesis that soil physical quality (SPQ) of the Cerrado biome in central Brazil depends on appropriate crop rotation and tillage practices in cotton (Gossypium hyrsutum [L.])‐based cropping systems and is critical to achieve optimal cotton yields (COT). SPQ of an Oxisol was accessed for layers of 0.0–0.1, 0.1–0.2, and 0.2–0.4 m under conventional tillage (CT) and no‐tillage (NT) systems, in different farming systems, such as cotton monoculture, crop succession, and crop rotation in central Brazil. Variables studied were soil bulk density, total porosity, air permeability, pore continuity index, water content at field capacity, relative saturation at field capacity, the least limiting water range (LLWR), and COT. Soil sampling was performed in 2014, and COT was obtained in the 2013 and 2014 cropping seasons. Conservationist practices, such as crop diversity and absence of soil tillage, improved water availability, enlarged the LLWR, and indicated that brachiaria cultivation positively influences the SPQ, whereas continuous soil tillage and less crop diversity adversely affected SPQ. COT was positively influenced by SPQ aspects regarding the increased water access in the 0.2–0.4 m layer of NT and in the 0.0–0.1 m of CT management. Differences in SPQ, as indicated by the LLWR, were reflected in differences in COT, as well as in soil air permeability in the CT treatments for the 2014 cropping season. Other SPQ variables had no relation to COT.