SOIL CARBON AND NITROGEN STOCKS AND GREENHOUSE GAS FLUXES IN SOIL CULTIVATED WITH JATROPHA SSP UNDER DIFFERENT MANAGEMENT PRACTICES

Abstract

In order to achieve the goals of reducing greenhouse gas (GHG) emissions from industrialized countries included in the Kyoto Protocol, researches have been developed to find alternatives that make the soil less sources and more sinks of GHG. Among the possible alternatives, reforestation with native species and/or intercropped with crops of economic interest (e.g. Jatropha ssp) can contribute to carbon sequestration and GHG emission reduction. Thus, the overall objective of this project is to estimate soil carbon and nitrogen stocks and GHG fluxes in Jatropha ssp chronosequences with different management practices in soil from two different climatic regions potentially located in south-central and northeast regions of Brazil. Soil samples will be collected in the 0-5, 5-10, 10-20, 20-30, 30-40, 50-60, 70-80 and 90-100 cm layers to evaluate soil C e N stocks and soil microbial biomass C and N content. CO2, N2O and CH4 fluxes will be measured using static chambers in triplicate in each study area. Soil carbon sequestration will be calculated by the difference between the GHG emissions and the soil carbon accumulation, converted to carbon equivalent units. These results will be used to simulated changes on soil C and N stocks and GHG emission as a function of different management practices in the cultivation of Jatropha ssp through the use of mathematical modeling.