Eight days in the life of a desert lichen: water relations and photosynthesis of teloschistes capensis in the coastal fog zone of the Namib Desert

Water content and CO2 exchange of the fruticose lichen TeIoschistes capensis were followed for a measuring period of eight days in the coastal fog zone of the Namib Desert north of Swakopmund, Namibia. Fog, dew, or high vapor pressure of the air alone can provide atmospheric water sources for photosynthetic activity. Through a combination of dew condensation and fog, hydration of the thaIli during the night resulted in predawn dry weight-related water contents of the thalIi greater than 100%.