Decreased cryogenic disturbance : one of the potential mechanisms behind the vegetation change in the Arctic

• Published in: Polar Biology
• Main Authors: Becher, Marina, Olofsson, Johan, Berglund, Louise, Klaminder, Jonatan
• Format: Article in Journal/Newspaper
• Language: English
• Published: Umeå universitet, Institutionen för ekologi, miljö och geovetenskap 2018
• Subjects: Patterned ground; Plant abundance; Non-sorted circles; Freeze/thaw-index; Cryogenic disturbance; Differential heave; Other Earth and Related Environmental Sciences; Annan geovetenskap och miljövetenskap; Abisko; Arctic; Polar Biology; Subarctic
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-112507; https://doi.org/10.1007/s00300-017-2173-5

During the last few decades, the Arctic has experienced large-scale vegetation changes. Understanding the mechanisms behind this vegetation change is crucial for our ability to predict future changes. This study tested the hypothesis that decreased cryogenic disturbances cause vegetation change in patterned ground study fields (non-sorted circles) in Abisko, Sweden during the last few decades. The hypothesis was tested by surveying the composition of plant communities across a gradient in cryogenic disturbance and by reinvestigating plant communities previously surveyed in the 1980s to scrutinise how these communities changed in response to reduced cryogenic disturbance. Whereas the historical changes in species occurrence associated with decreased cryogenic disturbances were relatively consistent with the changes along the contemporary gradient of cryogenic disturbances, the species abundance revealed important transient changes highly dependent on the initial plant community composition. Our results suggest that altered cryogenic disturbances cause temporal changes in vegetation dynamics, but the net effects on vegetation communities depend on the composition of initial plant species. Originally included in thesis in manuscript form 2016 with title: Decreased cryogenic disturbance : one of the potential mechanisms behind the shrubification of non-sorted circles in subarctic Sweden.