Seasonal controlling factors of CO exchange in a semiarid shrubland in the Chihuahuan Desert, Mexico.

The still significant uncertainties associated with the future capacity of terrestrial systems to mitigate climate change are linked to the lack of knowledge of the biotic and abiotic processes that regulate CO net ecosystem exchange (NEE) in space/time. Mainly, rates and controls of CO exchange from arid ecosystems, despite dominating the global trends in interannual variability of the terrestrial CO sink capacity, are probably the most poorly understood of all. We present a study on rates and controls of CO exchange measured with the eddy covariance (EC) technique in the Chihuahuan Desert in the Northeast of Mexico, to understand how the environmental controls of the NEE switch throughout the year using a multilevel approach.