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

Abstract

Brazil 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.

Humic Acid Improves Zn Fertilization in Oxisols Successively Cultivated with Maize–Brachiaria

“…The results reported in this study showed that HA promoted positives effects on maize, and guaranteed a residual Zn for brachiaria plants grown in sequence to maize, in a soil type-dependent way. However, maize–brachiaria cultivated in a sequence is widely performed in Brazilian cropping areas [ 3 ]; there is no study reporting how HA-Zn interaction exerts influence on the brachiaria cultivated in sequence to maize. Evaluating only the effect of HA-Zn interaction in single cultivation of coffee seedlings, Just et al [ 10 ] reported that the application of 50 mg kg −1 C-HA increased the solution Zn in alkalinized soils (pH > 7.2), probably due to the Zn–HA complexation.…”

“…Regarding tolerance to Zn, maize ( Zea mays ) is highly sensitive, while some grass plants such as brachiaria are less affected by low levels of Zn in the growth media [ 2 ]. The maize–brachiaria cultivation sequence is adopted in many Brazilian cropping areas [ 3 ]. The efficient use and adequate Zn fertilization are key issues to increase food production in Brazilian soils [ 2 ].…”

“…In tropical soils, Zn is prone to be immobilized in the soil mineral phase, but little is known regarding the humic fertilization–Zn interaction on plant nutrition and growth. Additionally, in the large area of Brazilian integrated crop-livestock systems, maize and brachiaria are simultaneously cultivated [ 3 ], and both crops show different responses to HA application and Zn fertilization [ 2 , 4 , 8 ].…”

A long‐term no‐tillage system can increase enzymatic activity and maintain bacterial richness in paddy fields

“…No-tillage (NT), an incipient management system used in Brazilian paddy fields, consists of sowing beneath cover crops residues on the soil surface. NT enhances both the soil chemical (L. H. C. Souza et al, 2018) and physical structure (Anghinoni, Tormena, Lal, Zancanaro, & Kappes, 2019). The microenvironmental changes caused by NT increase microbial biomass and decrease the metabolic quotient (da Silva et al, 2014).…”

Effects of land use, tillage management, and crop diversification on soil physical quality in Cerrado agricultural systems

“…Biopores can even drive the root development for the subsequent crop (Han et al, 2015(Han et al, , 2016. Another important topic is that crop diversification adds crop residues differing in quantity and quality, often resulting in increased biochemical interactions between plants and soil microorganisms (Reich et al, 2012;Pires et al, 2020;Venter et al, 2016), alleviating soil compaction, and improving soil structure and water infiltration (Anghinoni et al, 2019;Blanco-Canqui et al, 2015). Soil structure drives critical processes and functions in the environment (Bronick & Lal, 2005;Rabot et al, 2018).…”