Chiara Molinari
Postdoc
The role of climate, forest fires and human population size in Holocene vegetation dynamics in Fennoscandia
Författare
Summary, in English
Questions: We investigated the changing role of climate, forest fires and human population size in the broad-scale compositional changes in Holocene vegetation dynamics before and after the onset of farming in Sweden (at 6,000 cal yr BP) and in Finland (at 4,000 cal yr BP). Location: Southern and central Sweden, SW and SE Finland. Methods: Holocene regional plant abundances were reconstructed using the REVEALS model on selected fossil pollen records from lakes. The relative importance of climate, fires and human population size on changes in vegetation composition was assessed using variation partitioning. Past climate variable was derived from the LOVECLIM climate model. Fire variable was reconstructed from sedimentary charcoal records. Estimated trend in human population size was based on the temporal distribution of archaeological radiocarbon dates. Results: Climate explains the highest proportion of variation in vegetation composition during the whole study period in Sweden (10,000-4,000 cal yr BP) and in Finland (10,000-1,000 cal yr BP), and during the pre-agricultural period. In general, fires explain a relatively low proportion of variation. Human population size has significant effect on vegetation dynamics after the onset of farming and explains the highest variation in vegetation in S Sweden and SW Finland. Conclusions: Mesolithic hunter-gatherer populations did not significantly affect vegetation composition in Fennoscandia, and climate was the main driver of changes at that time. Agricultural communities, however, had greater effect on vegetation dynamics, and the role of human population size became a more important factor during the late Holocene. Our results demonstrate that climate can be considered the main driver of long-term vegetation dynamics in Fennoscandia. However, in some regions the influence of human population size on Holocene vegetation changes exceeded that of climate and has a longevity dating to the early Neolithic.
Avdelning/ar
- Institutionen för naturgeografi och ekosystemvetenskap
- BECC: Biodiversity and Ecosystem services in a Changing Climate
- MERGE: ModElling the Regional and Global Earth system
Publiceringsår
2018-05
Språk
Engelska
Sidor
382-392
Publikation/Tidskrift/Serie
Journal of Vegetation Science
Volym
29
Issue
3
Dokumenttyp
Artikel i tidskrift
Förlag
International Association of Vegetation Science
Ämne
- Physical Geography
- Ecology
- Environmental Sciences related to Agriculture and Land-use
Nyckelord
- Climate
- Fire
- Human population size
- Pollen
- REVEALS plant abundance
- Variation partitioning
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1100-9233