Fig. 7.
a Year round activity (2012–2013) monitoring at all sites: the moss-dominated crust (Öland), the Toninia sedifolia-dominated crust (Gössenheim), the cyanobacteria-dominated crust (Hochtor, due to breakage by heavy snow cover, data between October 2012 and July 2013 were lost, monitoring continues for one more year) and the Diploschistes diacapsis-dominated crust (Tabernas). b Diurnal CO2-gas exchange measurements of the cyanobacteria-dominated crust under natural conditions at Hochtor from July 26th to August 3rd 2012; from top to bottom: air temperature 1 m above ground; crust water content expressed as mm precipitation equivalent; ambient light intensity; CO2-gas exchange, positive = net photosynthesis, negative = respiration