Carbon lability of soil and aggregates in crop sequences in the no-tillage system

• Grant number: 20/05295-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2020
• End date: May 31, 2021
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: José Eduardo Corá
• Grantee: Jéssica Alves Simielli
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Being one of the largest carbon reservoirs, the soil must be managed properly to reduce the emission of greenhouse gases, thus increasing the organic carbon in the soil - COS. The no-tillage system (NT) contributes to the increase of the COS and, consequently, improving its quality, being the soil structure the attribute that is most influenced by the use and management of the soil. The present work aims to evaluate the water stable aggregates and determine the organic carbon content and its fractions (particulate organic carbon - COP and organic carbon associated with minerals-COAM), in different sizes of soil aggregates submitted to the no-till system for 20 years with different crop sequences. The statistical design was in bands with 3 randomized blocks in a 3x7 factorial scheme. The treatments are composed of three sequences of summer crops: corn monoculture (CC), soybean monoculture (SS) and soybean/corn rotation (SC) with soybean and corn intercropping year by year; and seven intercropping crops: corn, sunflower, oilseed radish, pearl millet, pigeon pea, grain sorghum, and sunn hemp, totaling 21 treatments with three replicates. Also, two treatments will be used for comparison with the NT, namely conventional soil tillage system (plowing and harrowing) and native vegetation.