Indicadores que determinam o aumento da fração estável da matéria orgânica e a manutenção de cátions básicos

Abstract

In the humid tropics, most soils have low natural fertility. Agriculture in this region faces several challenges, such as: preserving the landscape and biodiversity, contributing to the reduction of CO2 in the atmosphere, reducing poverty and promoting food security for farming families. Thus, we evaluated the effects of adding legume biomass with and without the application of Ca, Si and urea, on the organic carbon content in the soil, and on the N content in the plant and corn productivity. The experiment was conducted from October 2021 to March 2023 at the State University of Maranhão, São Luís, Maranhão, Brazil. The experimental design was established in randomized blocks (DBC), four replications and eight treatments. The treatments consisted of arrangements of legumes with calcium, silicon and urea. The results show that Ca has a strong relationship with COAM. The variables Si and TOC demonstrate the effectiveness of the application of polyvalent cations in increasing carbon concentrations in the soil. Productivity showed a positive correlation with COAM, Si, and Ca. Therefore, strategies and management such as the one carried out in this research can help the humid tropics to store carbon and maintain high productivity rates in the future.