Behavior of nitrate and potassium ions in Oxisol with vinasse application submitted to different treatments.

• Grant number: 11/04145-8
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2012
• End date: February 28, 2013
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Marcio Roberto Soares
• Grantee: Fabiane Karen Godoy
• Host Institution: Centro de Ciências Agrárias (CCA). Universidade Federal de São Carlos (UFSCAR). Araras , SP, Brazil

Abstract

Vinasse is a liquid effluent with high organic load and has significant concentrations of nitrogen (N-NO3-and NH4+-N) and potassium (K+). Nitrogen compounds from vinasse, like nitrate, can pollute soil and groundwater. The CETESB Report on Quality of Groundwater noted the growth in the concentration of nitrate in groundwater, including areas explored with sugar cane. Studies showed that there is necessary to treat vinasse before its disposal on the soil in order to promote the degradation of organic compounds and toxic substances. This research project aims at assessing the pollution potential of vinasse in natura, concentrated and treated chemically and biologically in soil and groundwater. Experiments will be conducted in laboratory and assess mainly the behavior of ions NO3-and K+ in Oxisol using the adsorption methods of batch type and the percolation through the soil column, including the simulation of groundwater level, seeking to meet the following objectives: (a) estimate the maximum adsorption of NO3- and K+ (b) study the mobility NO3-and K+ and chemical changes (COD, pH and EC) in soil columns under different dosages (rate, m3 ha-1) vinasse, (c) verify that the treatment of vinasse, the rate and frequency used may create risks of contamination of soil and groundwater and (d) contribute to the improvement of the standard CETESB P4.231, suggesting the inclusion of the levels of NO3- in the equation of application rates and treatment of vinasse before its application.