Production of N2O, CH4, and CO2from soils in the tropical savanna during the dry season

✍ Scribed by W. M. Hao; D. Scharffe; P. J. Crutzen; E. Sanhueza

• Publisher: Springer Netherlands
• Year: 1988
• Tongue: English
• Weight: 621 KB
• Volume: 7
• Category: Article
• ISSN: 0167-7764
• DOI: 10.1007/bf00048256

✦ Synopsis

Emissions ofN20, CH 4, and CO2 from soils at two sites in the tropical savanna of central Venezuela were determined during the dry season in February 1987. Measured arithmetic mean fluxes of N20, CH4, and CO2 from undisturbed soil plots to the atmosphere were 2.5 x 109, 4.3 x 10 I°, and 3.0 x 1013 molecules cm -2 s -I , respectively. These fluxes were not significantly affected by burning the grass layer. Emissions of N20 increased fourfold after simulated rainfall, suggesting that production of N20 in savanna soils during the rainy season may be an important source for atmospheric N20. The CH 4 flux measurements indicate that these savanna soils were not a sink, but a small source, for atmospheric methane. Fluxes of CO2 from savanna soils increased ninefold two hours after simulated rainfall, and remained three times higher than normal after 16 hours. More research is needed to clarify the significance of savannas in the global cycles ofN20, CH4, CO2, and other trace gases, especially during the rainy season.