Carbon and water fluxes of a laurisilva cloud forest in Anaga Biosphere Reserve (Tenerife, Canary Islands)

The consequences of fog in the gas exchange dynamics of cloud forests are not fully understood. Eddy covariance and meteorological measurements were carried out above a laurisilva cloud forest in Anaga Biosphere Reserve (Tenerife, Canary Islands) during a three-month period. Fog affected CO2 fluxes (F-CO2) and evapotranspiration (ET) such that F-CO2 and ET were significantly lower during times when fog water was artificially collected at the site. Despite such a reduction in diurnal carbon net assimilation due to fog presence, CO2 fluxes remained relatively high (F-CO2 > 5 mu mol m(-2) s(-1)) most of the day, thus leading to a greater water use efficiency of the laurisilva vegetation under cloud immersion.