Short-term variations in flux and spatial variability of soil CO2 in native forest

Abstract

Soil is an important compartment of carbon in terrestrial ecosystem, retaining substantial quantity of this element in organic forms, mainly in forest areas. The understanding of the factors that affect the fluxes of soil CO2 is the basic to the reduction of emissions of greenhouse gases to the atmosphere. The objective of this work was to evaluate the patterns of spatial variability of soil CO2 flux in native forest in a very clayey dystroferric Red Latosol (Oxisol), in Lavras city, Minas Gerais state, Brazil. A grid of 32 points was delimited, regularly spaced in 5 m distance, in which the CO2 flux and environmental factors (water evaporation, temperature and soil moisture) and attributes related to fertility (pH, base soil saturation and exchangeable aluminium), structure (bulk density and total porosity) and soil organic matter (total organic carbon, microbial biomass carbon) were evaluated. Simple linear correlation analyses indicated that the soil CO2 emissions are a complex phenomenon, being not satisfactorily explained by a single soil or environment attribute. The CO2 flux did not present spatially structured variability in the adopted sampling scale, having a distribution that was considered as randomized.

doi: 10.4336/2010.pfb.30.62.85