Influence of crop biodiversification on the functional groups of soil carbon fraction.

• Grant number: 24/17979-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2024
• End date: October 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Maurício Roberto Cherubin
• Grantee: Gabriela Ferreira Codling
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 21/10573-4 - Center for Carbon Research in Tropical Agriculture (CCARBON), AP.CEPID

Abstract

The greatest challenge facing humanity is to produce more nutritious food to alleviate global hunger while protecting the environment and mitigating climate change. This is especially relevant in Brazil, where agriculture is vital to both the economy and societal development. As a global agricultural leader, Brazil must balance increasing food production with adopting sustainable practices that reduce environmental impact and enhance resilience to climate change. Diversifying cropping systems by incorporating cover crops has been shown to improve soil multifunctionality, enhancing key processes such as increasing soil organic carbon (16%), soil organic nitrogen (18%), particulate organic carbon (53%), aggregate stability (200% in the 0-5 cm layer), and enzyme activity after three years of management. Soil organic carbon (SOC) plays a crucial role in soil health and ecosystem services, with different carbon pools serving distinct functions: particulate organic matter (POM) provides food for soil organisms, occluded organic matter supports soil aggregation, and mineral-associated organic matter (MOAM) ensures long-term carbon sequestration. However, little is known about the impact of cover crop diversification on the functional groupings of soil carbon fractions. By exploring the mechanisms of carbon stabilization and sequestration linked to cover crop biomass, we aim to understand how these practices influence the composition and functionality of soil carbon pools, which are critical for maintaining soil health and ecosystem sustainability. Identifying these functional carbon groups is crucial, as their properties and functions in the soil vary based on their chemical composition. The sampling will include different levels of cover crop diversification in the savannah region, with soil samples collected from depths of 0-10, 10-20, and 20-30 cm. This will test the hypothesis that highly diversified systems (mixes of cover crops) promote greater carbon stability and improve the functionality of carbon groupings in the soil, contributing to improved soil health and climate change mitigation.