A. Hill tops of the "Glauer Berge", a sandy terminal morain with an open pine forest and microbiotic soil crusts in the foreground (overview).
B. Close-up view of a microbiotic crust (3 - 5 mm thick).
C. Light micrograph of a growing crust sample. Algal filaments (Zygnema spp.) build up a network, embedding the quartz grains on the soil surface.
D. Light micrograph of an algal filament (Zygnema spp.), associated with smaller fungal filamens.