From barren substrate to mature tundra - lichen colonization in the forelands of Svalbard glaciers

This paper contributes to studies on the lichen biota of Arctic regions. The research was carried out in the forelands of eight glaciers and in the mature tundra surrounding them. Study areas were located in two parts of Svalbard: in the Kongsfjord (forelands of Austre Brøggerbreen, Vestre Brøggerbreen, Austre Lovénbreen, Midtre Lovénbreen, and Vestre Lovénbreen) and in the Isfjord (forelands of Rieperbreen, Svenbreen, and Ferdinandbreen). In each foreland and in the mature tundra surrounding it, a series of 1-m² plots was established, within which a percentage cover for each species was determined. In total, 133 lichens and one lichenicolous fungus were recorded. Nineteen species were recorded for the first time in Svalbard: Agonimia allobata, Atla wheldonii, Bacidia herbarum, Catolechia wahlenbergii, Epigloea soleiformis, Lecanora behringii, Lepraria subalbicans, Leptogium arcticum, Pertusaria pseudocorallina, Placidiopsis custnani, Protothelenella corrosa, Pyrenidium actinellum, Spilonema revertens, Stereocaulon saxatile, Thelocarpon sphaerosporum, Toninia coelestina, Verrucaria elaeina, Verrucaria murina, and Verrucaria xyloxena. The lichen richness was the lowest in the Ferdinandbreen foreland (24 species) and the highest in the Rieperbreen foreland (82 species). Significant differences in species composition were found among the forelands studied, except for Austre and Vestre Brøggerbreen whose lichen composition was similar. The differences in lichen composition between mature tundra in the vicinity of the following forelands were identified: Vestre Brøggerbreen and Svenbreen, Austre Brøggerbreen and Svenbreen, and Austre Brøggerbreen and Ferdinandbreen. The most dominant group of lichens in both forelands and mature tundra were chlorolichens, not cyanolichens.