Differential interception and evaporation of fog, dew and water vapour and elemental accumulation by lichens explain their relative abundance in a coastal desert

► Non-rainfall atmospheric moisture intercepted by lichens greater than rainfall. ► Atmospheric water vapour is the greatest source of moisture intercepted by lichens. ► Non-rainfall atmospheric moisture determines lichen abundance and distribution. ► Lichen chemical composition does not correspond with that in oceanic fog water. ► Elemental absorption greatest in lichens with thin thalli.