02051naa a2200265 a 450000100080000000500110000800800410001910000210006024500810008126000090016252013240017165000120149565000200150765000140152765300150154165300160155665300240157270000200159670000160161670000190163270000170165170000180166870000190168677300800170519814722019-10-30       2013    bl uuuu     u00u1 u    #d1 aCABRAL, O. M. R.  aFluxes of CO2 above a sugarcane plantation in Brazil.h[electronic resource]  c2013  aFluxes of CO2 were measured above a sugarcane plantation using the eddy-covariance method covering two growth cycles, representing the second and third re-growth (ratoons) harvested with stubble burning. The total net ecosystem exchange (NEE) in the first cycle (second ratoon, 393 days long) was ?1964 ± 44 g C m?2; the gross ecosystem productivity (GEP) was 3612 ± 46 g C m?2 and the ecosystem respiration (RE) was 1648 ± 14 g C m?2. The NEE and GEP totals in the second cycle (third ratoon, 374 days long) decreased 51% and 25%, respectively and RE increased 7%. Accounting for the carbon emitted during biomass burning and the removal of stalks at harvest, net ecosystem carbon balance (NECB) totals were 102 ± 130 g C m?2 and 403 ± 84 g C m?2 in each cycle respectively. Thus the sugarcane agrosystem was approximately carbon neutral in the second ratoon. Yield in stalks fresh weight (SFW) attained the regional average (8.3 kg SFW m?2). Although it was a carbon source to the atmosphere, observed productivity (6.2 kg SFW m?2) of the third ratoon was 19% lower than the regional average due to the lower water availability observed during the initial 120 days of re-growth. However, the overall water use efficiency (WUE) achieved in the first cycle (4.3 g C kg?1 H2O) decreased only 5% in the second cycle.  abiomass  aeddy covariance  asugarcane  aCO2 fluxes  aRespiration  aSoil water deficits1 aROCHA, H. R. da1 aGASH, J. H.1 aLIGO, M. A. V.1 aRAMOS, N. P.1 aPACKER, A. P.1 aBATISTA, E. R.  tAgricultural and Forest Meteorology, Amsterdamgv. 182-183, p. 54-66, 2013.