Geochemical mobility, speciation and transfer of metals, nutrients and organic carbon in Plinthosols under prolonged flooding

• Grant number: 16/01270-0
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2016
• End date: November 30, 2019
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Alfredo Borges de Campos
• Grantee: Alfredo Borges de Campos
• Host Institution: Instituto de Geociências (IG). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated researchers: Dalton Belchior Abdala ; Jacinta Enzweiler ; Jerusa Schneider ; Ricardo Marques Coelho ; Ricardo Perobelli Borba ; Wanilson Luiz Silva

Abstract

Plinthosols occur in humid and semi-humid tropical regions from several continents. The geochemistry of Plinthosols is sensitive to changes in the hydromorphic conditions which can be modified, among other factors, by natural or irrigation flooding. Previous studies performed in Plinthosols under the influence of prolonged flooding by irrigation show high geochemical mobility of Fe and Al. Likewise, the geochemical mobility of other elements, speciation and geochemical transfer, may be influenced by this hydrological condition. This is a relevant research theme but not well understood. The objectives of this project are 1) to simulate in the laboratory prolonged flooding and anoxic and reducing conditions to verify geochemical mobility of metals, nutrients associated with fertilizers and organic carbon in Plinthosols found in areas of native vegetation and irrigated for 18 and 28 years; 2) to determine the chemical species present in Plinthosols during prolonged flooding and under anoxic and reducing conditions; 3) to verify the geochemical transfer potential of elements from Plinthosols to natural water during periods of prolonged flooding and under anoxic and reducing conditions. The research will be carried out with samples of Plinthosols collected in areas of the irrigation project Luis Alves do Araguaia, State of Goiás, Brazil, where previous studies were performed by the principal investigator. The research will provide new knowledge on the geochemical mobility, speciation and transfer of elements in Plinthosols which are important for improving basic science and supporting soil and water conservation initiatives and best management practices in irrigated areas. (AU)