Small fragments of thesoil block of about 1 cm2 (lichen thallus together with the underneath
soil) were embedded in water or in the O.C.T. Tissue Tekembedding solution (Sakura, Finetech Europe BV, Zoeterwoude,Netherlands) and cut with a cryotome (Leica CM 3000, Heidelberg,Germany) into 30 m thick sections