Soil organic matter in land use change areas under sugarcane cultivation in south central region of Brazil

Abstract

The expansion of sugarcane to grassland areas creates questions about the environmental sustainability of ethanol. The land use change native vegetation - pasture - sugarcane can result in negative impacts on soil. In this regard, soil organic matter (SOM) is presented as a sensitive indicator of these changes. Thus, this project aims to assess the impacts of land use change in the quantity and quality of SOM in chronosequences of native vegetation - pasture - sugarcane in the South Central region of Brazil. The research will be developed in three locations: Jataí - GO, Valparaiso - SP and Ipaussu - SP. In these places, the soil will be sampled in nine points for each use, up to 1 m deep. Carbon stocks (C) and nitrogen (N) will be quantified as well as the source of C in the soil and in different size fractions of SOM, by physical fractionation and 13C isotope technique. Structural changes in the MOS will assess by 13C nuclear magnetic resonance spectroscopy (NMR) and Laser Induced Fluorescence (LIF). The labile carbon (CL) and CMI will also be determined. Moreover, simulations will be made in stocks of C and N in different land uses, through mathematical modeling. At the end, the data will be integrated by means of multivariate statistics (principal component analysis). It is expected that the results generated in this study may contribute to the assessment of environmental sustainability in areas of expansion of cane sugar in the South Central region of Brazil. (AU)