Microbial Interactions in Silicate Rock Weathering: Effects on Soil Properties and Carbon Stabilization

• Grant number: 25/00432-5
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2025
• End date: March 31, 2028
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Fernando Dini Andreote
• Grantee: Rafael Lima Oliveira
• 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

Rock powders release nutrients, alter soil chemical properties, and promote carbon sequestration through both organic and inorganic pathways. However, the weathering dynamics of these materials involve complex interactions in which microorganisms play a central role. Although studies on mineral solubilization are ongoing, the interaction between the soil microbiome and minerals, particularly their effects on soil physical properties and carbon stabilization, remains poorly understood. In this research project, we will conduct three sequential studies to investigate the role of microbial communities in the weathering of rock powders and the formation of secondary minerals that improve soil aggregation and water retention, contribute to organic matter stabilization, and promote inorganic carbon formation. In the first study, we will evaluate the potential of microbially mediated mineral weathering and its effects on soil physical properties, selecting the type and dose of rock powder that induce the most significant changes in these properties. The second study will examine the role of microbial diversity in mineral weathering, evaluating chemical, physical, and mineralogical changes in soils treated with rock powders, along with the nutritional and physiological responses of cultivated plants. The third study will investigate the contribution of microbial necromass and root exudates to the stabilization of 13C in minerals formed during rock powder weathering. These studies aim to deepen the understanding of the biogeochemical processes involved in rock powder weathering, establishing a foundation for agronomic and environmental applications that integrate microbial community interactions with soil property changes, focusing on carbon stabilization to mitigate climate change.