Towards an ecological understanding of soil health in Brazilian agriculture: A path analysis

• Grant number: 24/21096-0
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: February 22, 2025
• End date: May 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Maurício Roberto Cherubin
• Grantee: Viviana Meneghini
• Supervisor: Andre Luiz Custodio Franco
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Institution abroad: Indiana University, United States
• Associated to the scholarship: 24/02508-6 - Soil health assessment in agricultural areas in Southern Brazil: an approach using multiple methodologies and application scales, BP.MS

Abstract

Conservation agriculture practices that improve soil health are key strategies to achieve production stability and make the production environment more resilient in a climate changing world. Metrics that represent soil health over large areas and in a simple way should be studied to facilitate sustainable land use and management practices. In this sense, the Soil Health Index (SHI), based on the directly measurement of multiple soil indicators, represents a robust quantitative approach that has been explored worldwide. Alternatively, simpler approached as been proposed, as the Management Quality Index (MQI), which consists of a potential qualitative metric of production practices and the SOHMA Soil Health Kit, is a simple tool that can be applied in the field. This study aims to evaluate the potential of Structural Equation Modeling (SEM) to unravel the complex processes linking soil health and crop productivity. By elucidating direct and indirect ecological mechanisms, we seek to understand how management practices influence key soil health indicators in contrasting agricultural systems in Brazil. To achieve the objective, different methodologies were used to assess soil health with different potentials for scalability at the field level. To this end, soil samples were collected in 13 areas at 0.0-0.30 m and 0.0-1.0 m layers, in contrasting management systems in the state of Rio Grande do Sul, Brazil. These samples are currently undergoing laboratory analysis to assess indicators. Specifically, during the BEPE, data on soil health and crop productivity indicators will be subjected to Structural Equation Modeling to represent, through intuitive graphical networks, the complex relationships involved and the direct and indirect ecological mechanisms by which management practices influence soil health indicators. Overall, with this project we hope that the adoption of management practices such as the use of soil cover will allow a positive influence on key indicators that support soil health (e.g., enzyme activity, C, P, K, pH, Ds, and soil aggregates) and in the productivity of commercial crops. Furthermore, such findings can contribute to advancing strategies to increase agricultural production while preserving food security in the context of climate change.