Surface flow of pesticides in a sewage sludge-treated typical eutroferric red latosol in corn crop: experimentation and simulation

• Grant number: 06/06469-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: April 01, 2007
• End date: June 03, 2007
• Field of knowledge: Agronomical Sciences - Agronomy
• Principal Investigator: Jussara Borges Regitano
• Grantee: Nélio Ricardo Do Amaral Castro
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

It is well known that pesticide runoff studies in soils are rare in Brazil, that the water demand for human consumption comes mainly from surface sources (springs and rivers), which should be preserved from pesticides contamination by appropriate management practices. Therefore, the main objective of this research is to investigate the influence of sewage sludge application on runoff of pesticides widely used in corn. An insecticide and a pre-emergent herbicide presenting relative high persistence and mobility will be chosen. The sewage sludge at rates of 0, 10, and 20 t/ha will be incorporated in the soil (a Rhodic Eutrudox), at the experimental area of the Instituto Agronômico de Campinas (IAC), SP. Samples of water and sediments will be collected under natural conditions for determination of their pesticide residue by high performance liquid chromatography (HPLC). In parallel, pesticides sorption and degradation potential will be evaluated using radiolabeled molecules, under laboratory conditions at Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP. The outputs of these studies will be used for modeling purposes. For the first time, it will let evaluate the accuracy of the PRZM and MACRO simulation models to predict pesticide runoff in Brazil, allowing their adaptation to our conditions. (AU)