Soil Enzymes: Evaluation as an Indicator of Soil Carbon Accumulation in Integrated Crop-Livestock-Forest Systems

• Grant number: 24/23281-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2025
• End date: February 28, 2026
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Ladislau Martin Neto
• Grantee: Vitoria Napolitano
• Host Institution: Embrapa Instrumentação Agropecuária. Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA). Ministério da Agricultura, Pecuária e Abastecimento (Brasil). São Carlos , SP, Brazil
• Associated research grant: 23/02444-5 - Understanding intensified and integrated production systems: from the quantum world to low-carbon agriculture, AP.PFPMCG.TEM

Abstract

It is necessary to investigate the relationship between soil carbon, microbial enzymes and soil health in the context of agribusiness, focusing on sustainability and mitigating environmental impacts such as atmospheric CO2 emissions and soil degradation. Integrated crop-livestock-forestry systems can be an excellent alternative, reconciling intensive land use and environmental sustainability, including situations of carbon sequestration in the soil. The decomposition of organic matter, driven by microbial activity, directly influences both the release of carbon and agricultural productivity. Soils with low levels of organic carbon are more vulnerable to erosion and loss of fertility, which reinforces the need to develop methods that preserve carbon and guarantee the balance of the ecosystem. Specific enzymes, such as ¿-glucosidase (BG) and arylsulfatase (ARYL), are fundamental in the carbon cycle and soil fertility, respectively, and have shown consistent results, especially in areas with grains. This proposal aims to assess whether the quantification of these enzymes (BG and ARYL), in ILPF systems and compared to reference areas, with native vegetation and degraded pastures, can be an indicator for the accumulation of carbon in the soil, advancing the understanding of soil health in integrated crop-livestock-forest systems. Soil carbon content will be analyzed using the international reference method Elemental Analyzer (CHN). Measurements of soil carbon content up to 10 cm will be carried out in this proposal and then compared with data on soil carbon stocks up to 1m, which will be made available during the execution of the thematic project to which this proposal is linked. Analyses of the soil organic matter quality indicator (HLIFS) will be obtained by laser-induced fluorescence measurements. The proposed analyses are expected to generate unprecedented data on soil health in ILPF systems, and attempt to correlate soil enzyme content and carbon accumulation and sequestration.