Strategies for Greenhouse Gas Mitigation in Pasture Systems

• Grant number: 25/01492-1
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: April 01, 2025
• End date: March 31, 2027
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Pastures and Forage Crops
• Principal Investigator: Carlos Guilherme Silveira Pedreira
• Grantee: Solange Garcia Holschuch
• 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

This study aims to reduce the reliance on nitrogen fertilizers in tropical pastures through sustainable strategies such as biological nitrogen fixation (BNF). Given Brazil's high dependence on imported fertilizers and the economic and environmental challenges associated with the use of mineral nitrogen, alternatives are being investigated to mitigate greenhouse gas (GHG) emissions and environmental degradation while simultaneously increasing pasture productivity.The study evaluates the effects of bacterial foliar inoculation with Azospirillum brasilense strains Ab-V5 and Ab-V6 (Az) and the intercropping of tropical grasses with legumes, such as forage peanut (Arachis pintoi Krapov. & W.C. Greg.) cv. BRS Mandobi and Macrotyloma axillare E. Mey (Verdc), both sown in pastures established with Urochloa brizantha (Hochst. ex A. Rich.) cv. Marandu.The research seeks to explore the individual effects of these strategies and their complementarity when integrated into multi-technological systems (Marandu grass + Az + Mandobi + Macrotyloma). The main focus is to assess nitrous oxide emission fluxes in the soil.The study aims to understand the efficiency of BNF in pasture systems under continuous stocking and moderate defoliation severity. Expected outcomes include enhanced sustainability in tropical livestock systems, reduced environmental impacts, and increased agroecosystem resilience. This work provides practical and innovative contributions to the agricultural sector, reinforcing the relevance of integrated technologies and appropriate management of tropical pastures.