References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-6-5315-2006

Methane emission from tropical savanna Trachypogon sp. grasses

Sanhueza

¹ Donoso

IVIC, Atmospheric Chemistry Laboratory, Caracas, Venezuela

24 11 2006

6 12 5315 5319

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Methane flux measurements from the soil-grass system were made during the wet season in unperturbed plots and plots where standing dry and green Trachypogon sp. grasses were clipped to just above the soil surface. Results support the surprising discovery that vegetation emits methane. The results of this work allows to infer that the savanna dry/green mixture of grasses produce methane at a rate of ~10 ng m−2 s−1, which is in agreement with early published soil-grass system fluxes. An extrapolation of this flux to the global savanna produces an annual emission much lower than the CH4 production recently suggested in the literature. On the other hand, during the wet season savanna soil consume CH4 at a rate of ~4.7 ng m−2 s−1. Therefore, the tropical savanna soil-grass system would make a modest contribution to the global budget of methane.

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