 |
| Titel |
CO2, CH4 and N2O fluxes from soil of a burned grassland in Central Africa |
| VerfasserIn |
S. Castaldi, A. Grandcourt, A. Rasile, U. Skiba, R. Valentini |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1726-4170
|
| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 7, no. 11 ; Nr. 7, no. 11 (2010-11-08), S.3459-3471 |
| Datensatznummer |
250005051
|
| Publikation (Nr.) |
 copernicus.org/bg-7-3459-2010.pdf |
|
|
|
|
|
| Zusammenfassung |
| The impact of fire on soil fluxes of CO2, CH4 and N2O was
investigated in a tropical grassland in Congo Brazzaville during two field
campaigns in 2007–2008. The first campaign was conducted in the middle of
the dry season and the second at the end of the growing season, respectively
one and eight months after burning. Gas fluxes and several soil parameters
were measured in each campaign from burned plots and from a close-by control
area preserved from fire. Rain events were simulated at each campaign to
evaluate the magnitude and duration of the generated gas flux pulses. In
laboratory experiments, soil samples from field plots were analysed for
microbial biomass, net N mineralization, net nitrification, N2O, NO and
CO2 emissions under different water and temperature soil regimes. One
month after burning, field CO2 emissions were significantly lower in
burned plots than in the control plots, the average daily CH4 flux
shifted from net emission in the unburned area to net consumption in burned
plots, no significant effect of fire was observed on soil N2O fluxes.
Eight months after burning, the average daily fluxes of CO2, CH4
and N2O measured in control and burned plots were not significantly
different. In laboratory, N2O fluxes from soil of burned plots were
significantly higher than fluxes from soil of unburned plots only above
70% of maximum soil water holding capacity; this was never attained in
the field even after rain simulation. Higher NO emissions were measured in
the lab in soil from burned plots at both 10% and 50% of maximum soil
water holding capacity. Increasing the incubation temperature from 25 °C to 37 °C negatively affected microbial growth, mineralization and
nitrification activities but enhanced N2O and CO2 production.
Results indicate that fire did not increase post-burning soil GHG emissions
in this tropical grasslands characterized by acidic, well drained and
nutrient-poor soil. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|