Soil CO2 production and transport in the drought experiment in Caxiuana National Forest, Para, Brazil.
Eleneide
Doff
Sotta, University of Goettingen, esotta@gwdg.de
(Presenting)
Rosiene
Keila da
Paixao, Museu Paraense Emilio Goeldi, rosienepaixao@hotmail.com
Brenda
Rocha
Guimaraes, Museu Paraense Emilio Goeldi, b_rock1202@hotmail.com
Alessandro
Rosario, Museu Paraense Emilio Goeldi, asrosario@museu-goeldi.br
Antônio
Carlos Lôla da
Costa, Universidade Federal do Para, lola@ufpa.br
Edzo
Veldkamp, University of Goettingen, eveldka@gwdg.de
Patrick
Meir, University of Edinburgh, pmeir@ed.ac.uk
Maria
de Lourdes Pinheiro
Ruivo, Museu Paraense Emilio Goeldi, ruivo@museu-goeldi.br
Luitgard
Schwendenmann, University of Wyoming, l_schwendenmann@hotmail.com
Soil CO2 concentration measurements can characterise the soil C pool and determine the effects of low soil water content in soil CO2 production and transport. The study site was composed of two plots of 1 ha (100m x 100m), the control plot (Plot A) and the treatment plot (Plot B). 70-90% of the rainfall was excluded from the soil of one plot using panels and gutters to deflect the rain out of the plot. The impact of this soil drought on forest carbon and water cycling was assessed by comparing the control and treatment plots.
We measured soil CO2 concentration in the soil profile in 4 shafts at each plot (in the control plot and in the plot with water exclusion). The samples were collected with syringes at depths 5, 10, 25, 50, 100, 200 and 300 cm and analysed in a gas chromatograph. Radon measurements were made in order to determine soil CO2 diffusivity.
We will show preliminary results on the CO2 production and transport rates. First results on CO2 concentration profiles show seasonality for both plots. CO2 concentration increases in the soil in the beginning of the wet season and falls as soon as the dry season starts.
Submetido por Eleneide Doff Sotta em 17-MAR-2004
Tema Científico do LBA: CD (Armazenamento e Trocas de Carbono)