Organomineral Interactions in Mangrove Soil under Different Salinity Conditions.

• Grant number: 25/00609-2
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: April 28, 2025
• End date: July 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Francisco Ruiz
• Grantee: Tainara Novaes Bispo
• Supervisor: Xose Lois Otero Perez
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Institution abroad: Universidade de Santiago de Compostela, Vida (USC), Spain
• Associated to the scholarship: 24/07430-5 - Effect of Increased Salinity on Organic Matter (De)stabilization Processes in Mangrove Soil: Implications for Future Climate Scenarios, BP.IC

Abstract

In the context of climate change, mangrove forests are essential coastal ecosystems due to their capacity for soil carbon sequestration and storage, protection against extreme weather events, fiber production, nutrient cycling, and serving as habitats and nurseries for vertebrates. However, despite their importance and resilience, mangroves remain highly vulnerable to climate change impacts, including increased salinity. The effects of salinity on soil organic carbon (SOC) dynamics and associated chemical reactions are still not fully understood. This study aims to investigate organomineral interactions (OMIs) in mangrove soils through sequential chemical extractions. The objective is to determine how these interactions, influenced by increased salinity, may enhance or inhibit the formation of such complexes. Sequential chemical extractions will be performed using various reagents (KCl, CuCl¿, sodium pyrophosphate, and ammonium oxalate) on mangrove soil samples subjected to different salinity conditions in a mesocosm experiment. These methods will allow the assessment of how increased salinity affects the stabilization of soil organic matter (SOM) through changes in OMIs involving calcium (Ca), magnesium (Mg), and poorly crystalline forms of aluminum (Al), iron (Fe), and silicon (Si). The concentration of carbon and extracted elements will be measured at each step. With the support of statistical methods (ANOVA, or non-parametric equivalents, and PCA), inferences about the types of OMIs involved will be possible. The findings are expected to contribute to a better understanding of carbon dynamics in mangrove soils under varying salinity conditions.