Water and energy fluxes from a woodland savanna (cerrado) in southeast Brazil

Abstract

AbstractStudy regionThe area of woodland savanna (cerrado) is located in southeast Brazil (21°36′ to 44′S, 47°34′ to 41′W).Study focusThe cerrado sensu-stricto savanna evapotranspiration was observed using the eddy-covariance method over three years.New hydrological insights for the regionThe first year total rainfall (R=1664mm) was 11% above the long-term rainfall (1498mm) and the total evapotranspiration (ET=1242mm) and water equivalent of available energy (Av=1835mm) were approximately 4% and 2% greater, respectively, than in the second year when the rainfall total was 5% lower than the long-term average. In the third year despite the total rainfall (1259mm) being 24% lower than the first year and 16% lower than the average, the totals of ET (1242mm) and Av (1815mm) were approximately the same.The small variation in the observed annual ET totals shows that in this cerrado vegetation the deep soil moisture content supports the ET in a dry year and the water available for recharging the soil profile and groundwater (∼R−ET) was dominated by the rainfall amount being significantly greater in the wet year (422mm) than in the dry year (13mm)