Are Oxisols under Cerrado AGROSSYSTEMS achieving a carbon and nitrogen saturation plateau?

• Grant number: 17/20602-6
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): May 01, 2018
• Status: Discontinued
• Field of knowledge: Agronomical Sciences - Agronomy
• Principal Investigator: Rafael Otto
• Grantee: Thales Meinl Schmiedt Sattolo
• Home Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated scholarship(s): 18/24376-3 - Elucidating the potential of subsoils for enhanced carbon stocks in oxisol, BE.EP.DR

Abstract

In the Cerrado region stand out agrosystems under crop rotation/succession management and intensive fertilizer application. Changes in the soil after years of cultivation are questions solved through the installation of long-term experiments, fundamental to understand these agricultural practices effects on soil. The objective of this study is to evaluate the effects of nitrogen fertilization and management systems on soybean and corn experiment on: (1) the application of soil C and N saturation model; (2) the soil C and N stocks. The evaluations will be done in an experiment located in Itiquira/MT under a randomized block design with subdivided plots and four replicates. The experiment belongs to a worldwide network called "Global Maize Project" of the International Plant Nutrition Institute. In the main plots were allocated three management systems (successions and crop rotation), while in the subplots were allocated four N levels at cover fertilization maize. The first soil sampling was done in the 0-10, 10-20 and 20-40 cm layers for evaluation of soil C and N saturation, and the C and N stability in the SOM pools and fractions at respective saturation degree relative to the management systems. The second sampling will be done aiming to evaluate the effect of nitrogen fertilization on the soil C and N stocks up to 100 cm depth, in which the soil density and the C and N content will be determined. Both effects (nitrogen fertilization and management system) will be correlated with C and N contributions from the crops comprising all experiment years.