Soil carbon stratification affected by long-term tillage and cropping systems in southern Brazil

Mitigation of soil compaction for boosting crop productivity at varying yield environments in southern Brazil

“…Thus, the use of grass species with vigorous roots, such as the polyculture of cover crops in this study, can improve the physical quality of compacted soils and benefit subsequent crops (Calonego & Rosolem, 2010). Furthermore, roots are a source of exudates and SOM, which stimulate aggregate formation and stabilization along the soil profile (Martins, Corá, Jorge, & Marcelo, 2009;Wendling, Jucksch, Mendonça, & Neves, 2005), especially in soils without mechanical disturbance (Ferreira et al, 2018;Nicoloso et al, 2018).…”

Copper and zinc fractions in the profile of an Inceptisol cultivated with apple in southern Brazil

“…The higher Cu content in the soil -mostly in the organic fraction (Cu OM ), compared with other fractions (Cu Res , Cu Min , Cu E and Cu Sol ), especially in the surface layer (0.0 -0.25 m), with increasing age of the orchards (eight years for O8 and 18 years for O18) and, therefore, a larger number of Cu-containing fungicide applications and higher nutrient-cycling time -can be attributed to high affinity and reactivity with the functional groups of the soil organic matter (Pérez-Novo et al 2008). Therefore, because Cu is part of the organic fraction, the adoption of conservation management practices in orchards is crucial, for example, the deposition and maintenance of plant residues on the soil surface helps maintain the levels of soil organic matter and the absence of soil disturbance minimizes the mineralization of organic matter (Ferreira et al 2013;López-Piñeiro et al 2013). Nevertheless, the migration of the Cu to a depth of 0.40 m in the soil of orchards O8 and O18 was observed through the level of Cu Total and Cu OM , Cu Min and Cu Res fractions, (Table 3, Figure 1).…”

Two decades of no-till in the Oberacker long-term field experiment: Part I. Crop yield, soil organic carbon and nutrient distribution in the soil profile

“…(Paustian et al, 1997;Smith et al, 1998;Follett, 2001;West and Post, 2002;Lal, 2004). de Oliveira Ferreira et al (2013) showed that C sequestration is affected by climate and soil type in tropical areas.…”

“…Omitting mechanical incorporation of crop residues into the topsoil results in a changed distribution of SOC with depth, with higher concentrations in layers close to the soil surface in no-till compared with conventional tillage (e.g. de Moraes Sá and Lal, 2009;de Oliveira Ferreira et al, 2013;Dikgwatlhe et al, 2014). However, the literature is not conclusive as to whether SOC stocks in the whole soil profile increase under no-till.…”