| 1. |
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| 2. |
- Alenius, Teija, et al.
(författare)
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The environment they lived in: anthropogenic changes in local and regional vegetation composition in eastern Fennoscandia during the Neolithic
- 2020
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Ingår i: Vegetation History and Archaeobotany. - : Springer Science and Business Media LLC. - 0939-6314 .- 1617-6278. ; 30, s. 489-506
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Tidskriftsartikel (refereegranskat)abstract
- Understanding about regional versus local changes in vegetation is critical in answering archaeological questions, in particular at a time when humans are assumed to have caused higher disturbances at local scales rather than regional scales; this is the case during the Neolithic. The aim of this paper is to assess the impact of Neolithic land use on regional and local vegetation dynamics, plant composition and disturbance processes (e.g. fire) in eastern Fennoscandia. We apply the Landscape Reconstruction Algorithm (LRA) to high-resolution pollen records from three lacustrine sediment cores that cover the Neolithic period. We calculate changes in vegetation composition and the rate of plant compositional change. Fire dynamics are estimated as an indicator of land use, although fire can result from both natural and anthropogenic disturbances. Our results show that during the Early Neolithic, changes were mainly driven by natural and climate-induced factors and vegetation composition and fire activity were similar at both regional and local scales. From ca. 4000 bc onwards, trends in vegetation and fire dynamics start to differ between regional and local scales. This is due to local land uses that are overshadowed at the regional scale by climate-induced factors. The use of the LOVE model in pollen analyses is therefore very useful to highlight local land uses that are not visible by using REVEALS.
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| 3. |
- Castelnuovo, Gianluca, et al.
(författare)
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What Is the Role of the Placebo Effect for Pain Relief in Neurorehabilitation? : Clinical Implications From the Italian Consensus Conference on Pain in Neurorehabilitation
- 2018
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Ingår i: Frontiers in Neurology. - : Frontiers Media SA. - 1664-2295. ; 9
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Forskningsöversikt (refereegranskat)abstract
- Background: It is increasingly acknowledged that the outcomes of medical treatments are influenced by the context of the clinical encounter through the mechanisms of the placebo effect. The phenomenon of placebo analgesia might be exploited to maximize the efficacy of neurorehabilitation treatments. Since its intensity varies across neurological disorders, the Italian Consensus Conference on Pain in Neurorehabilitation (ICCP) summarized the studies on this field to provide guidance on its use.Methods: A review of the existing reviews and meta-analyses was performed to assess the magnitude of the placebo effect in disorders that may undergo neurorehabilitation treatment. The search was performed on Pubmed using placebo, pain, and the names of neurological disorders as keywords. Methodological quality was assessed using a pre-existing checklist. Data about the magnitude of the placebo effect were extracted from the included reviews and were commented in a narrative form.Results: 11 articles were included in this review. Placebo treatments showed weak effects in central neuropathic pain (pain reduction from 0.44 to 0.66 on a 0-10 scale) and moderate effects in postherpetic neuralgia (1.16), in diabetic peripheral neuropathy (1.45), and in pain associated to HIV (1.82). Moderate effects were also found on pain due to fibromyalgia and migraine; only weak short-term effects were found in complex regional pain syndrome. Confounding variables might have influenced these results.Clinical implications: These estimates should be interpreted with caution, but underscore that the placebo effect can be exploited in neurorehabilitation programs. It is not necessary to conceal its use from the patient. Knowledge of placebo mechanisms can be used to shape the doctor-patient relationship, to reduce the use of analgesic drugs and to train the patient to become an active agent of the therapy.
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| 4. |
- Cipollini, Monica, et al.
(författare)
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Polymorphisms within base and nucleotide excision repair pathways and risk of differentiated thyroid carcinoma
- 2016
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Ingår i: DNA Repair. - : Elsevier BV. - 1568-7864. ; 41, s. 27-31
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Tidskriftsartikel (refereegranskat)abstract
- The thyrocytes are exposed to high levels of oxidative stress which could induce DNA damages. Base excision repair (BER) is one of the principal mechanisms of defense against oxidative DNA damage, however recent evidences suggest that also nucleotide excision repair (NER) could be involved. The aim of present work was to identify novel differentiated thyroid cancer (DTC) risk variants in BER and NER genes. For this purpose, the most strongly associated SNPs within NER and BER genes found in our previous GWAS on DTC were selected and replicated in an independent series of samples for a new case-control study. Although a positive signal was detected at the nominal level of 0.05 for rs7689099 (encoding for an aminoacid change proline to arginine at codon 117 within NEIL3), none of the considered SNPs (i.e. rs7990340 and rs690860 within RFC3, rs3744767 and rs1131636 within RPA1, rs16962916 and rs3136166 in ERCC4, and rs17739370 and rs7689099 in NEIL3) was associated with the risk of DTC when the correction of multiple testing was applied. In conclusion, a role of NER and BER pathways was evoked in the susceptibility to DTC. However, this seemed to be limited to few polymorphic genes and the overall effect size appeared weak.
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| 5. |
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| 6. |
- Clear, Jennifer, et al.
(författare)
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Holocene fire in Fennoscandia and Denmark
- 2014
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Ingår i: International Journal of Wildland Fire. - 1448-5516. ; 23:6, s. 781-789
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Tidskriftsartikel (refereegranskat)abstract
- Natural disturbance dynamics, such as fire, have a fundamental control on forest composition and structure. Knowledge of fire history and the dominant drivers of fire are becoming increasingly important for conservation and management practice. Temporal and spatial variability in biomass burning is examined here using 170 charcoal and 15 fire scar records collated throughout Fennoscandia and Denmark. The changing fire regime is discussed in relation to local biogeographical controls, regional climatic change, anthropogenic land use and fire suppression. The region has experienced episodic variability in the dominant drivers of biomass burning throughout the Holocene, creating a frequently changing fire regime. Early Holocene biomass burning appears to be driven by fuel availability. Increased continentality during the mid-Holocene Thermal Maximum coincides with an increase in fire. The mid–late Holocene front-like spread of Picea abies (Norway spruce) and cooler, wetter climatic conditions reduce local biomass burning before the onset of intensified anthropogenic land use, and the late Holocene increase in anthropogenic activity created artificially high records of biomass burning that overshadowed the natural fire signal. An economic shift from extensive subsistence land use to agriculture and forestry as well as active fire suppression has reduced regional biomass burning. However, it is proposed that without anthropogenic fire suppression, the underlying natural fire signal would remain low because of the now widespread dominance of P. abies.
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| 7. |
- Guido, Maria Angela, et al.
(författare)
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Climate and vegetation dynamics of the Northern Apennines (Italy) during the Late Pleistocene and Holocene
- 2020
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Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791. ; 231, s. 1-17
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Tidskriftsartikel (refereegranskat)abstract
- This study reconstructs the regional vegetation and climate dynamics between the upper Late Pleistoceneand Holocene around Pian del Lago, a coastal mountain marshland located at 831 m asl in westernLiguria (NW-Italy), based on the pollen analysis of a 13 m-long sediment core. The record provided aunique opportunity to study a poorly documented period in northern Italy and across many parts ofsouthwestern Europe. We propose an event stratigraphy based upon the identification of seven interstadials(NAI-7 to NAI-1) spanning the upper Late Pleistocene. The correlation with other terrestrialrecords in Italy, and with Mediterranean marine sequences and the Greenland ice cores, permitted acoherent reconstruction of main environmental changes from >~43,000 cal. BP. Significantly, the pollenrecord indicates the persistence of a mesophilous mountain vegetation cover, mainly composed ofQuercus (deciduous and evergreen), Abies, Fagus and Alnus over the whole time period recorded. At theLast Glacial Maximum (LGM) and during the Late Würm Lateglacial, despite the presence of steppicvegetation composed of Artemisia, woodlands dominated by Pinus, with Abies, Picea, Fagus, Alnus andBetula are present. This forest composition provides an important insight into the history of Picea insouthern Europe and Late Pleistocene refugia for mesophilous species. During the Early Holocene, Pinusis first replaced by Abies and then by deciduous Quercus and mixed temperate species as the dominantforest component. Both arboreal and herbaceous anthropogenic pollen indicators only make theirappearance during the Late Holocene, attesting to the increasing importance of human activities.
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| 8. |
- Hannon, Gina E., et al.
(författare)
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Factors influencing late-Holocene vegetation dynamics and biodiversity on Hallands Väderö, SW Sweden : A statistical evaluation
- 2022
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Ingår i: Holocene. - : SAGE Publications. - 0959-6836. ; 32:11, s. 1317-1326
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Tidskriftsartikel (refereegranskat)abstract
- Forest composition characteristic of the Mid-Holocene has survived on Hallands Väderö, an island nature reserve off the south west coast of Sweden. Current veteran Tilia and Quercus trees contribute to a remarkably rich biodiversity of fungi, bryophytes, lichens and insects. Understanding which potential factors influence Holocene vegetation dynamics can support efforts to protect biodiversity, but the role of grazing and browsing has previously been difficult to evaluate because of the lack of long-term datasets. Palaeoecological analyses over the last c. 3000 years from a pond on the island reveal sustained presence of Quercus, Alnus, Tilia, Corylus and Ulmus, alongside increasing Fagus in recent centuries. Changes in grazing pressure have been documented since AD 1665 and a statistical approach was used to calculate the relative importance of grazing pressure, climate variability, and fire activity on the dynamics of selected taxa. Grazing was the main factor reducing population size of Fagus, Alnus, Tilia and Corylus on the island over the period AD 1665–1858, with warm winter temperatures and summer humidity having significant positive influences in the last millennium for Quercus, Alnus, Tilia and Corylus. The survival of large numbers of red-listed species is likely to be due to the continuity of large old trees, ancient forest composition and a distinctive disturbance history in a favourable climate.
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| 9. |
- Hannon, Gina E., et al.
(författare)
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The reconstruction of past forest dynamics over the last 13,500 years in SW Sweden
- 2018
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Ingår i: The Holocene. - : SAGE Publications. - 0959-6836 .- 1477-0911. ; 28:11, s. 1791-1800
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Tidskriftsartikel (refereegranskat)abstract
- Evidence for unbroken continuity of tree taxa over the last c. 13,500 years is presented from a biodiversity ‘hotspot’ nature reserve in south-west Sweden.Forest composition, continuity, fire and disturbance events are reconstructed using palaeoecological methods. A lake record reveals that Pinus sylvestris,Betula spp., Salix spp., Populus tremula and Hippophae rhamnoides were the initial trees scattered in a semi-open, steppe environment. This developedinto forest with Pinus, Betula, Corylus, Alnus, Ulmus and Populus with evidence for frequent fires. Deciduous trees became more significant as fires becameless frequent and Quercus, Fraxinus and Tilia expanded. Fire frequencies increased again in the Bronze Age probably associated with anthropogenic useof the forest, and the first Fagus sylvatica pollen was recorded. Burning continued through the Iron Age, but charcoal is briefly absent for a period oftenreferred to as the ‘Late Iron Age Lull’. The forest re-expanded with successions involving Juniperus, but with an altered composition from the earlier mixeddeciduous community, to one dominated by Fagus. This is coincident with the first pollen records for Picea abies. The early Holocene mixed forest withfrequent low-intensity fires is potentially associated with the greatest diversity of red-listed insect species. Forest continuity and the fragmented reservoirpopulations of old deciduous trees in the Fagus-dominated forest today are likely to have been critical in preserving the present-day, species-rich, rareepiphytic flora, wood-inhabiting fungi and invertebrate communities. As many of these forest fragments may become more vulnerable with future climatechange, tree diversity with some disturbance may become essential for survival of the endangered saproxylic species.
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| 10. |
- Hannon, Gina E., et al.
(författare)
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Vegetation dynamics and Fire History in Färnebofjärden National Park, Central Sweden
- 2021
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Ingår i: The Holocene. - : SAGE Publications. - 0959-6836 .- 1477-0911. ; 31:1, s. 28-37
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Tidskriftsartikel (refereegranskat)abstract
- Palaeoecological studies can identify past trends in vegetation communities and processes over long time scales. Pollen, plant macrofossils and charcoalanalyses are used to reconstruct vegetation over the last 6400 years and provide information about former human impact and disturbance regimesin Färnebofjärden National Park, Central Sweden. Three specific conservation planning topics were addressed: (1) the changing ratio of conifers tobroadleaved trees; (2) the origin and history of the river meadows and the biodiverse Populus tremula meadows; (3) the role of fire in the maintenanceof biological values. Early diverse mixed broadleaved forest assemblages with pine were followed by significant declines of the more thermophilic forestelements prior to the expansion of spruce in the Iron Age. The rise to dominance of spruce was a ‘natural’ process that has been exaggerated byanthropogenic disturbance to artificially high levels today. The initial river meadow communities were facilitated by fire and frequent flooding events, butsubsequent dynamics have more definitely been supported by human activities. Rural abandonment during the last 100 years has led to woody successions.Fire has been a continual disturbance factor with an influence on conservation issues such as Picea abies dominance and the maintenance of diverse, nonforestcommunities. Present occurrence of fire is unusually low, but natural fire frequencies are increasing in the region.
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| 11. |
- Kuosmanen, Niina, et al.
(författare)
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The role of climate, forest fires and human population size in Holocene vegetation dynamics in Fennoscandia
- 2018
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Ingår i: Journal of Vegetation Science. - : Wiley-Blackwell. - 1100-9233 .- 1654-1103. ; 29:3, s. 382-392
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Tidskriftsartikel (refereegranskat)abstract
- QuestionsWe 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 6,000cal yr BP) and in Finland (at 4,000calyr BP). LocationSouthern and central Sweden, SW and SE Finland. MethodsHolocene 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. ResultsClimate explains the highest proportion of variation in vegetation composition during the whole study period in Sweden (10,000-4,000cal yr BP) and in Finland (10,000-1,000cal 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. ConclusionsMesolithic 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.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
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| 16. |
- Molinari, Chiara, et al.
(författare)
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Exploring potential drivers of European biomass burning over the Holocene: a data-model analysis
- 2013
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Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-8238 .- 1466-822X. ; 22:12, s. 1248-1260
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Tidskriftsartikel (refereegranskat)abstract
- AimTo reconstruct spatial and temporal patterns of European fire activity during the Holocene and to explore their potential drivers, by relating biomass burning to simulated biotic and abiotic parameters. LocationEurope. MethodsHolocene fire activity was investigated based on 156 sedimentary charcoal records from lakes and peat bogs across Europe. Charcoal data covering the last 9000 years were statistically compared with palaeoclimate data derived from the Max Planck Institute for Meteorology/University of Wisconsin-Madison Earth System Model, with vegetation and fire indices simulated with the dynamic vegetation model lpj-guess and with two independent scenarios of past anthropogenic land-cover change. ResultsThe combined sedimentary charcoal records suggest that there was little fire activity during the early and the middle Holocene compared with recent millennia. A progressive increase in fire frequency began around 3500cal. yr bp and continues into the late Holocene. Biomass burning rose sharply from 250cal. yr bp onwards, reaching a maximum during the early Industrial Era and then declining abruptly. When considering the whole Holocene, the long-term control of fire is best explained by anthropogenic land-cover change, litter availability and temperature-related parameters. Main conclusionsWhile the general patterns found across Europe suggest the primary role of vegetation, precipitation and temperature-related parameters in explaining fire dynamics during the early Holocene, the increase in fire activity observed in the mid-late Holocene is mainly related to anthropogenic land-cover changes, followed by vegetation and temperature-related parameters. The 20th-century decline in biomass burning seems to be due to increased landscape fragmentation and active fire suppression policies. Our hypothesis that human activities played a primary role in Holocene biomass burning across Europe could be tested by improved palaeoclimate reconstructions and more refined representations of anthropogenic fires in climate and vegetation models.
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| 17. |
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| 18. |
- Molinari, Chiara, et al.
(författare)
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Fire Dynamics in Boreal Forests Over the 20th Century : A Data-Model Comparison
- 2021
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Ingår i: Frontiers in Ecology and Evolution. - : Frontiers Media SA. - 2296-701X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Fire regimes across the world are expected to be altered by continuing variations in socio-economic conditions and climate. Current global fire-vegetation models are able to represent the present-day fire activity, but it is unclear how well they can simulate past or future scenarios. Here we use sedimentary charcoal-based biomass burning reconstructions to evaluate fire probability and total carbon flux emitted to the atmosphere per year simulated by the dynamic global vegetation model LPJ-GUESS with its incorporated fire model SIMFIRE-BLAZE across the boreal region during the last century. The analyses were run for the whole time period (1900–2000 CE), as well as for the intervals 1900–1950 CE and 1950–2000 CE. The data–model comparison for the 20th century reveals a general disagreement in trends between charcoal reconstructions (with decreasing or stable trends) and simulations (showing an overall increase) at both global (boreal forests) and continental scales (North America and Fennoscandia), as well as for most of the regional sub-areas (Canada, Norway and Sweden). The only exceptions are Alaska and Finland/Russia Karelia, where all the variables increase. Negative correlations between observations and model outputs are also recorded for the two different sub-periods, except for Alaska and North America during the time interval 1900–1950 CE, and Norway and Finland/Russia Karelia between 1950 and 2000 CE. Despite several uncertainties in charcoal records, main differences between modeled and observed fire activity are probably due to limitations in the representation of the human impact on fire regime (especially connected to forest management and landscape fragmentation) in the model simulations.
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| 19. |
- Molinari, Chiara, et al.
(författare)
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Fire-vegetation interactions during the last 11,000 years in boreal and cold temperate forests of Fennoscandia
- 2020
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Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791. ; 241
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Tidskriftsartikel (refereegranskat)abstract
- The long-term ecological interactions between fire and the composition of dominant trees and shrubs in boreal and cold temperate Fennoscandian forests are still under discussion. We hypothesized that fire-prone taxa should abound during periods and regions characterized by higher fire disturbance, while fire-intolerant taxa should dominate when and where fire activity is low. Biomass burning (BB) is here investigated based on 69 sedimentary charcoal records. For the same sites, the relative contribution of pollen-based reconstructions of dominant vegetation cover divided into three different fire-sensitivity classes is explored by means of a statistical approach. The overall patterns found across Fennoscandia suggest that Ericaceae (mainly Calluna), Pinus, Betula and Populus are strongly positively correlated with multi-millennial variability of BB in both boreal and cold temperate forests, confirming their fire-prone character (taxa adapted/favoured by burning). Positive but much weaker (and not always significant) relationships also exist between long-term trends in BB and Fagus, Quercus, Corylus, Alnus, Juniperus, Carpinus and Salix, fire-tolerant taxa that survive low/moderate intense fires because of specific functional traits or their rapid, enhanced regeneration after fire. A strong negative significant correlation is instead detected between BB and Picea, Ulmus Tilia, Fraxinus, which are fire-intolerant taxa and can locally disappear for a short time after a fire. This large-scale analysis supports our initial hypothesis that tree and shrub dominance was closely linked to biomass burning since the onset of the Holocene in the study regions. Fire was an important ecosystem disturbance in Fennoscandia influencing long-term vegetation dynamics and composition over the last 11,000 years, although human activities probably altered the strength of fire-vegetation interactions during more recent millennia.
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| 20. |
- Molinari, Chiara, et al.
(författare)
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Interdisciplinary approach for reconstructing an alder-based historical agricultural practice of the Eastern Ligurian Apennines (NW Italy)
- 2016
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Ingår i: Environmental Archaeology. - 1461-4103. ; 21:1, s. 31-44
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Tidskriftsartikel (refereegranskat)abstract
- Data from four soil profiles studied through pollen and macroscopic charcoal analyses were used to identify specific palynological assemblages associated with a traditional land-use system documented in the Eastern Ligurian Apennines (NW Italy) between the 18th and early 20th century, concerning a cyclical use of grey alder plots for temporary cultivations involving to the use of controlled fire. This is the first attempt to verify on palynological evidence some hypotheses raised by previous historical ecology studies about the consequences of this agricultural practice (recently named alnocoltura) on past and present vegetation. Our investigations underline (1) high percentages of anthropogenic pollen indicators, (2) increase of Ericaceae percentages, (3) low pollen percentages of Alnus, (4) high macrocharcoal concentrations and (5) high values of palynological richness during periods affected by the alnocoltura cycle according to the historical sources. Similar patterns are also detectable in pollen diagrams from two adjacent peat bogs. The paper shows the strength of an interdisciplinary methodology (field observations, cartographical and archival historical data, palynological and archaeological investigations) for studies of past land-use systems. By demonstrating the necessity of a long-term prospective in environmental reconstructions for the preservation of the cultural landscape, one of the important elements of this research is its potential contribution to issues of habitat management and nature-conservation policy. Further analyses are needed to test the replicability and reliability of the hypotheses derived from this study.
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| 21. |
- Molinari, Chiara, et al.
(författare)
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Lagorara
- 2013
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Ingår i: La natura della montagna. - 9788897264224 ; , s. 529-537
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Bokkapitel (refereegranskat)
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| 22. |
- Molinari, Chiara, et al.
(författare)
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Long-term vegetation history of a Picea abies stand in south-western Norway : implications for the conservation of biological values
- 2005
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Ingår i: Biological Conservation. - : Elsevier. - 1873-2917. ; 126:2, s. 155-165
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Tidskriftsartikel (refereegranskat)abstract
- The development of a forest stand in south-eastern Norway during the last 9000 years is investigated by pollen and charcoal analyses. The aims are to identify factors that have influenced current biodiversity, which includes the lichen Usnea longissima, and examine the immigration and establishment of the current dominant tree Picea abies. Fire has been a variable but major disturbance factor at the site throughout the study period but has ceased during the last 100 years. Picea immigration was primarily a natural process but local establishment occurred after a major disturbance. Cultural impact began 3500 years ago during the Bronze Age, but was most intensive between AD 1600 and AD 1900. It led to the local extinction of deciduous trees and created a biodiversity bottleneck that facilitated the rise to dominance of Picea. Guidelines are proposed for future management designed to preserve and enhance local biological values.
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| 23. |
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| 24. |
- Molinari, Chiara, et al.
(författare)
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Rachixina
- 2013
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Ingår i: La natura della montagna. - 9788897264224 ; , s. 391-401
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Bokkapitel (refereegranskat)
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| 25. |
- Molinari, Chiara, et al.
(författare)
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The climate, the fuel and the land use: long-term regional variability of biomass burning in boreal forests
- 2018
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Ingår i: Global Change Biology. - : Wiley. - 1365-2486 .- 1354-1013. ; 24:10, s. 4929-4945
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Tidskriftsartikel (refereegranskat)abstract
- The influence of different drivers on changes in North American and European boreal forests biomass burning (BB) during the Holocene was investigated based on the following hypotheses: land use was important only in the southernmost regions, while elsewhere climate was the main driver modulated by changes in fuel type. BB was reconstructed by means of 88 sedimentary charcoal records divided into six different site clusters. A statistical approach was used to explore the relative contribution of (a) pollen‐based mean July/summer temperature and mean annual precipitation reconstructions, (b) an independent model‐based scenario of past land use (LU), and (c) pollen‐based reconstructions of plant functional types (PFTs) on BB. Our hypotheses were tested with: (a) a west‐east northern boreal sector with changing climatic conditions and a homogeneous vegetation, and (b) a north‐south European boreal sector characterized by gradual variation in both climate and vegetation composition. The processes driving BB in boreal forests varied from one region to another during the Holocene. However, general trends in boreal biomass burning were primarily controlled by changes in climate (mean annual precipitation in Alaska, northern Quebec, and northern Fennoscandia, and mean July/summer temperature in central Canada and central Fennoscandia) and, secondarily, by fuel composition (BB positively correlated with the presence of boreal needleleaf evergreentrees in Alaska and in central and southern Fennoscandia). Land use playedonly a marginal role. A modification towards less flammable tree species (by promoting deciduous stands over fire‐prone conifers) could contribute to reduce circumboreal wildfire risk in future warmer periods.
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