Diurnal and Seasonal Cycles of CO<sub>2</sub> Fluxes in the low Deciduous Forest in the South of Sonora, Mexico

HR: 1400h
AN: GC23A-09 [Abstracts]
TI: Diurnal and Seasonal Cycles of CO₂ Fluxes in the low Deciduous Forest in the South of Sonora, Mexico
AU: * Perez-Ruiz, E
EM: qeliperez@gmail.com
AF: Instituto Tecnologico de Sonora, 5 de Febrero 818 Sur, Cd. Obregon, Son 85000, Mexico
AU: Garatuza-Payan, J
EM: garatuza@itson.edu.mx
AF: Instituto Tecnologico de Sonora, 5 de Febrero 818 Sur, Cd. Obregon, Son 85000, Mexico
AU: Garcia-Calleja, M T
EM: mary_triny_@hotmail.com
AF: Instituto Tecnologico de Sonora, 5 de Febrero 818 Sur, Cd. Obregon, Son 85000, Mexico
AU: Watts, C J
EM: watts@nirvana.uson.mx
AF: Universidad de Sonora, Blvd. Luis Encinas y Rosales, Hermosillo, Son , Mexico
AB: The Deciduous Seasonal Forest or Low Deciduous Forest (LDF) is one of the most diverse and most contrasting ecosystems in Mexico. It can be found from the south of the northern state of Sonora to the border of Mexico with Guatemala. This ecosystem is very important to the region since it represents a big area of vegetal cover close to the biggest cities of South Sonora (hence, endangered), and can be considered as a sink of carbon dioxide. In the present study, the CO₂ fluxes over the LDF were analyzed in the period from June 2004 to December 2006. The CO₂, latent and sensible heat, and momentum fluxes were measured using the Eddy covariance method. The Eddy covariance system consists of a 3-D sonic anemometer (CSAT3, Campbell Scientific), a gas analyzer (LI-7500, LI-COR), and diverse meteorological equipment controlled by a datalogger (CR5000, Campbell Scientific). The measures were made at 10Hz, collecting, storing and averaging the measurements every 30 minutes. The same type of cover is present in, at least, 3 km around the tower. The results show a large range in the diurnal variation of the CO2 fluxes, with values from -1.5 (day) to 0.8 (night) mg CO₂ m^-
2s^-1 (negative values indicate uptake) in the summer, and from -0.5 to 0.15 mg CO₂ m^-2s^-
1 during the winter. This ecosystems presents a clear growing season corresponding to the rain season in the summer, nevertheless, even in the dry season, the LDF can be considered as a sink of carbon dioxide during some hours around the midday.
DE: 0426 Biosphere/atmosphere interactions (0315)
DE: 0428 Carbon cycling (4806)
DE: 1615 Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 4805, 4912)
SC: Global Climate Change [GC]
MN: 2007 Joint Assembly