| 1. |
- Berntsson, Annika, 1979-, et al.
(författare)
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An evaluation of a chironomid-based summer temperature reconstruction from west 1 central Sweden covering the last millennium
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Annan publikation (populärvet., debatt m.m.)abstract
- Here we present a lake sediment study from west central Sweden that covers the last thousand years. The study site Lake Spåime is a shallow, hydrologically open lake situated above the present tree line. We applied chironomid analysis with the aim to reconstruct mean July air temperature at a high temporal resolution and we evaluated our reconstruction with significance tests and comparison with observed meteorological data. We examined the relationship between changes in chironomid-inferred July temperature, isotope hydrology and minerogenic detrital input. We also assessed the influence of running water and semi-terrestrial/terrestrial chironomids. The inferred July air temperatures ranged from 8.5˚C to 11.6˚C (mean 9.6˚C) over the past millennium. The temperatures inferred with running water- and terrestrial taxa removed was similar, but with a 0.6 ˚C higher amplitude. The results of significance testing were inconclusive. Comparison with meteorological data showed that the chironomid-based July air temperatures were similar during the last 110 years. Individual years when chironomid-inferred July air temperatures were lower than the instrumental data were characterized by low June air temperatures and high amounts of winter precipitation. From this, we assume that late snowmelt led to cool melt water input in July which in turn caused a decoupling between water and air temperatures causing too low inferred temperatures. Inferred July temperatures show similarities and discrepancies with reconstructions derived from other proxies in the region, such as tree-ring and sea surface temperature records, and fail to reconstruct the cold summer conditions characteristic of the years between AD 1650 and 1750. We conclude that the Spåime July temperature reconstruction was partly biased, possibly because of major changes in the Spåime catchment system that influenced the chironomids. For example, changes in hydrology caused by shifts in seasonality and amount of precipitation may have triggered changes in sediment erosion and deposition rates, affecting the chironomid composition to a larger extent than mean July air temperatures. Future challenges include examination of the temperature sensitivity of chironomid taxa and continued critical assessment of individual chironomid inferred temperature reconstructions, not only against other temperature proxies but also against proxies for variations in hydrology.
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| 2. |
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| 3. |
- Berntsson, Annika, et al.
(författare)
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Late Holocene high precipitation events recorded in lake sediments and catchment geomorphology, Lake Vuoksjavratje, NW Sweden
- 2015
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Ingår i: Boreas. - : Wiley. - 0300-9483 .- 1502-3885. ; 44:4, s. 676-692
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we show the potential of combining multi-proxy analysis of lake sediments with catchment geomorphology to better understand palaeoenvironmental changes. Previous studies have suggested that alpine lakes in N Sweden may be highly sensitive to variations in catchment erosion and precipitation, and that this sensitivity may influence ecologically based reconstructions of past temperature changes. We analysed lake sediments covering the last 5100 years from the alpine Lake Vuoksjavratje in NW Sweden in order to identify different erosional regimes in the lake catchment, sediment sources and lake sedimentary processes, which ultimately affect the palaeoecological record. The measured proxies include elemental geochemistry from XRF core scanning, grain size, sediment accumulation rates, fraction of terrestrial organic carbon and geomorphological mapping, supported by previously published chironomid and total organic carbon data. From the integrated results we identified time intervals when increased intensity of precipitation altered sedimentation and lake catchment erosional processes. The most prominent event occurred c. 2900 cal. a BP and is interpreted to be the result of excessive precipitation, possibly related to the climatic shift towards cooler and wetter conditions referred to as the 2.8 ka event.
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| 4. |
- Berntsson, Annika, 1979-, et al.
(författare)
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Late Holocene high precipitation events recorded in lake sediments and catchment geomorphology, Lake Vuoksjávrátje, NW Sweden
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- In this paper, we highlight the importance of combining multi-proxy analysis of lake sediments with associated catchment geomorphology to better understand the late Holocene palaeoenvironmental evolution in a high latitude Alpine lake in N Sweden. Previous studies have suggested that such lakes may be highly sensitive to variations in catchment erosion and variations in precipitation, and that this sensitivity may influence ecologically-based reconstructions of past temperature changes. Here we have analysed lake sediments covering the last 5100 years from Lake Vuoksjávrátje in NW Sweden to identify different erosional regimes in the lake catchment and to identify sediment sources and lake sedimentary processes, which ultimately affect the palaeoecological record. Methods that were used include XRF core scanning, grain size analysis and geomorphological mapping, supported by previously published chironomid, total organic carbon and carbon/nitrogen data. From the integrated results we identify time intervals when increased amounts/intensity of precipitation altered sedimentation and lake catchment erosional processes. The most prominent event in our record occurred between 3090 and 2750 cal. a BP and is interpreted to be the result of excessive precipitation in relation to the 2.8 ka event. By combining the multi-proxy analysis of a lake sediment core with a detailed catchment characterisation it is possible to reach a better understanding of the processes active within the lake catchment, the factors governing the erosional regimes and the way these are recorded in lake sediments. For future palaeoclimatological research based on lake sediments we recommend increasing the integration of catchment geomorphology, sedimentology and palaeoecology.
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| 5. |
- Berntsson, Annika, et al.
(författare)
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Late-Holocene temperature and precipitation changes in Vindelfjallen, mid-western Swedish Lapland, inferred from chironomid and geochemical data
- 2014
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Ingår i: The Holocene. - : SAGE Publications. - 0959-6836 .- 1477-0911. ; 24:1, s. 78-92
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Tidskriftsartikel (refereegranskat)abstract
- In this article, we present results from a palaeolimnological study from Lake Vuoksjavratje in the mountain tundra region in the Vindelfjallen Mountains, northwest Sweden. We suggest that the influence of precipitation may be one of the factors causing discrepancies between chironomid-based late-Holocene July temperature (JulyT) reconstructions from Fennoscandia. We combine quantitative temperature reconstruction using chironomids for the last 5100 years with qualitative analysis of chironomid composition and geochemical analyses, such as x-ray fluorescence (XRF), total organic carbon (TOC) and C/N analysis. The studied sequence is dated by Pb-210, Cs-137 and 11 C-14 datings from terrestrial macrofossils. The aim of the study was to use chironomids to reconstruct late-Holocene summer temperature variation on a multi-centennial to centennial timescale and to use geochemical data to identify periods during which the changes in chironomid composition might have been forced by environmental variables other than temperature, such as within lake processes or precipitation. Based on ordination techniques, and a comparison between chironomid-inferred JulyTs and changes in minerogenic sedimentation with regional temperature and wetness records, it is concluded that the JulyT signal was modulated by precipitation. The proxies indicate that both JulyT and annual precipitation have influenced the chironomid communities in Lake Vuoksjavratje, and that catchment-related processes caused by enhanced precipitation have overridden the summer temperature signal between 3000 and 2200 cal. yr BP, and between 1050 and 100 cal. yr BP.
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| 6. |
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| 7. |
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| 8. |
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| 9. |
- Berntsson, Annika, 1979-
(författare)
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The sensitivity of Swedish alpine lakes to hydro-climatic changes during the Late Holocene
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The thesis objective is to use lake sediments to investigate the relationships between chironomids, as proxy for temperature, and δ18O and minerogenic in-wash, as precipitation proxies, in northern Sweden during the Late Holocene. Three lakes along a N–S transect in the Scandes were studied using biological, geochemical and physical sediment properties, together with numerical methods. Emphasis was put on changes in hydrological and erosional regimes and the configurations of lake catchments in an attempt to avoid misinterpretation of the climate signals. Mean July air temperatures were inferred from the chironomid composition in sediment records covering the last 5000 yrs in Vindelfjällen Mountains in Mid Lapland and the last 1000 yrs in Jämtland. The temperature reconstructions underwent significance tests, suggesting reliable results for the Vindelfjällen reconstruction but not the Jämtland reconstruction. Data from XRF core scanning and grain size variations, interpreted together with catchment geomorphology, suggested periods with increased fluvial erosion. A major flood event occurred at the Vindelfjällen site c. 2800 cal. yr BP. Furthermore, this record indicates stream flow and wetland surface erosion during the last 1200 yrs. Seasonal variations in the amount of precipitation, reflecting changes in atmospheric circulation during the last 1000 yrs, were reconstructed based on δ18O in diatoms from one lake in Jämtland and one in northern Lapland. Relatively higher summer precipitation was inferred between AD 1000 and 1080, AD 1300 and 1440, and during the early 19th century as a result of a positive Arctic Oscillation mode. Changes in chironomid composition in the Jämtland lake were concurrent with shifts in δ18Odiatom suggesting indirect responses to circulation changes. Changes in precipitation are suggested to be an important factor that may cause the spatially variable results among chironomid-based July air temperature reconstructions in Scandinavia.
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| 10. |
- Breidenstein, Annika, et al.
(författare)
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PrgE: an OB-fold protein from plasmid pCF10 with striking differences to prototypical bacterial SSBs
- 2024
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Ingår i: Life Science Alliance. - : Life Science Alliance. - 2575-1077. ; 7:8
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Tidskriftsartikel (refereegranskat)abstract
- A major pathway for horizontal gene transfer is the transmission of DNA from donor to recipient cells via plasmid-encoded type IV secretion systems (T4SSs). Many conjugative plasmids encode for a single-stranded DNA-binding protein (SSB) together with their T4SS. Some of these SSBs have been suggested to aid in establishing the plasmid in the recipient cell, but for many, their function remains unclear. Here, we characterize PrgE, a proposed SSB from the Enterococcus faecalis plasmid pCF10. We show that PrgE is not essential for conjugation. Structurally, it has the characteristic OB-fold of SSBs, but it has very unusual DNA-binding properties. Our DNA-bound structure shows that PrgE binds ssDNA like beads on a string supported by its N-terminal tail. In vitro studies highlight the plasticity of PrgE oligomerization and confirm the importance of the N-terminus. Unlike other SSBs, PrgE binds both double- and single-stranded DNA equally well. This shows that PrgE has a quaternary assembly and DNA-binding properties that are very different from the prototypical bacterial SSB, but also different from eukaryotic SSBs.
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| 11. |
- Breidenstein, Annika, et al.
(författare)
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Structural and functional characterization of TraI from pKM101 reveals basis for DNA processing
- 2023
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Ingår i: Life Science Alliance. - : Life Science Alliance, LLC. - 2575-1077. ; 6:4
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Tidskriftsartikel (refereegranskat)abstract
- Type 4 secretion systems are large and versatile protein machineries that facilitate the spread of antibiotic resistance and other virulence factors via horizontal gene transfer. Conjugative type 4 secretion systems depend on relaxases to process the DNA in preparation for transport. TraI from the well-studied conjugative plasmid pKM101 is one such relaxase. Here, we report the crystal structure of the trans-esterase domain of TraI in complex with its substrate oriT DNA, highlighting the conserved DNA-binding mechanism of conjugative relaxases. In addition, we present an apo structure of the trans-esterase domain of TraI that includes most of the flexible thumb region. This allows us for the first time to visualize the large conformational change of the thumb subdomain upon DNA binding. We also characterize the DNA binding, nicking, and religation activity of the trans-esterase domain, helicase domain, and full-length TraI. Unlike previous indications in the literature, our results reveal that the TraI trans-esterase domain from pKM101 behaves in a conserved manner with its homologs from the R388 and F plasmids.
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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. |
- Gad, Helge, et al.
(författare)
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MTH1 inhibition eradicates cancer by preventing sanitation of the dNTP pool
- 2014
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Ingår i: Nature. - : Nature Publishing Group. - 0028-0836 .- 1476-4687. ; 508:7495, s. 215-221
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Tidskriftsartikel (refereegranskat)abstract
- Cancers have dysfunctional redox regulation resulting in reactive oxygen species production, damaging both DNA and free dNTPs. The MTH1 protein sanitizes oxidized dNTP pools to prevent incorporation of damaged bases during DNA replication. Although MTH1 is non-essential in normal cells, we show that cancer cells require MTH1 activity to avoid incorporation of oxidized dNTPs, resulting in DNA damage and cell death. We validate MTH1 as an anticancer target in vivo and describe small molecules TH287 and TH588 as first-in-class nudix hydrolase family inhibitors that potently and selectively engage and inhibit the MTH1 protein in cells. Protein co-crystal structures demonstrate that the inhibitors bindin the active site of MTH1. The inhibitors cause incorporation of oxidized dNTPs in cancer cells, leading to DNA damage, cytotoxicity and therapeutic responses in patient-derived mouse xenografts. This study exemplifies the non-oncogene addiction concept for anticancer treatment and validates MTH1 as being cancer phenotypic lethal.
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| 17. |
- Helmens, Karin, et al.
(författare)
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Early MIS 3 glacial lake evolution, ice-marginal retreat pattern and climate at Sokli (northeastern Fennoscandia)
- 2009
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Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 28:19-20, s. 1880-1894
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Tidskriftsartikel (refereegranskat)abstract
- Lake development at Sokli, northern Finland, is traced through the analysis of diatoms and other siliceous micro-fossils in a 2-meter thick minerogenic, laminated clay-silt deposit dated to the early part of Marine Isotope Stage (MIS) 3. Fluctuating water levels and changes in lake extent depicted by the siliceous micro-fossil record, together with lithology, suggest that an important part of the sediment sequence was deposited in a glacial lake. The proxy-based glacial lake evolution is tested using a Digital Elevation Model and geomorphologic evidence including eskers dated to the early MIS 3 Tulppio Interstadial at Sokli. Despite the apparent ice-dammed nature of the lake, the sediment is relatively rich in fossils and there are limited signs of re-deposition of older fossil material. The siliceous micro-fossil record together with data from other proxies previously analysed in the same sediment samples provides a coherent picture of past environmental changes around the Sokli site. This is most probably due to the sheltered position of the coring-site in a lake embayment. Quantitative climate reconstructions based on the diatom record show mean July air temperatures as high as present-day values at Sokli, and the temperature ranges indicated by the diatom record are in agreement with temperature reconstructions based on chironomids. The position of Sokli in the northeastern portion of the central area of the Scandinavian glaciations and the northern retreat pattern implies that an important part of eastern Fennoscandia was deglaciated during the early MIS 3 warming event.
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Linderholm, Hans W., 1968, et al.
(författare)
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Arctic hydroclimate variability during the last 2000 years – current understanding and research challenges
- 2018
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Ingår i: Climate of the Past. - : Copernicus GmbH. - 1814-9324 .- 1814-9332. ; 14, s. 473-514
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Forskningsöversikt (refereegranskat)abstract
- Reanalysis data show an increasing trend in Arctic precipitation over the 20th century, but changes are not homogenous across seasons or space. The observed hydroclimate changes are expected to continue and possibly accelerate in the coming century, not only affecting pan-Arctic natural ecosystems and human activities, but also lower latitudes through the atmospheric and ocean circulations. However, a lack of spatiotemporal observational data makes reliable quantification of Arctic hydroclimate change difficult, especially in a long-term context. To understand Arctic hydroclimate and its variability prior to the instrumental record, climate proxy records are needed. The purpose of this review is to summarise the current understanding of Arctic hydroclimate during the past 2000 years. First, the paper reviews the main natural archives and proxies used to infer past hydroclimate variations in this remote region and outlines the difficulty of disentangling the moisture from the temperature signal in these records. Second, a comparison of two sets of hydroclimate records covering the Common Era from two data-rich regions, North America and Fennoscan-dia, reveals inter- and intra-regional differences. Third, building on earlier work, this paper shows the potential for providing a high-resolution hydroclimate reconstruction for the Arctic and a comparison with last-millennium simulations from fully coupled climate models. In general, hydroclimate proxies and simulations indicate that the Medieval Climate Anomaly tends to have been wetter than the Little Ice Age (LIA), but there are large regional differences. However, the regional coverage of the proxy data is inadequate, with distinct data gaps in most of Eurasia and parts of North America, making robust assessments for the whole Arctic impossible at present. To fully assess pan-Arctic hydroclimate variability for the last 2 millennia, additional proxy records are required.
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| 22. |
- Massuanganhe, Elidio A., 1982-, et al.
(författare)
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Palaeogeography and dynamics of the deltaic wetland of Save River, Mozambique
- 2018
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Ingår i: Palaeogeography, Palaeoclimatology, Palaeoecology. - : Elsevier BV. - 0031-0182 .- 1872-616X. ; 489, s. 64-73
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Tidskriftsartikel (refereegranskat)abstract
- Many mangrove wetland systems in deltaic environments are negatively affected by massive sedimentation fromriver inflows. In this paper we use the example of the Save River delta to assess the palaeogeographic distributionof mangrove wetlands and to analyze their dynamics. To track past occurrences of mangrove wetlands in thestudy area we have integrated sedimentological data with siliceous microfossil analysis combined with AMSradiocarbon and OSL dating. The results show a fine-grained deposit with an approximate thickness of 2 m,present at different sampling sites. In the upper deltaic plain, the deposit is interbedded between sand layers,while in the lower deltaic plain the deposit occupies the uppermost stratigraphic position. In most of thesampling sites the deposit shows a succession with brackish-marine diatoms at the bottom of the sequence whilethe upper part shows only scattered occurrences. Based on sedimentological and microfossil characteristics wehave interpreted the layer to represent a mangrove wetland deposit. The development of the deposit in the studyarea is suggested to have been initiated around 3100 cal. yr BP, induced by sea-level rise. Thereafter, the developmentfollowed the combined effect of a sea-level fall and delta progradation processes. In some areas,particularly in the proximal part of the delta, the mangrove deposit has developed progressively on top of thedelta-front. From around 1300 years ago (OSL) onwards, massive alluvial sedimentation impacted the mangroveecosystem. However, the retreat of mangrove wetland coincided with a regional fall of sea level. At the edges ofthe alluvial deposit, the current mangrove ecosystem has reclaimed the habitat in some sectors where gullyerosion has exposed the once extinct mangrove habitat.
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| 23. |
- Risberg, Jan, et al.
(författare)
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Strandförskjutning under mesolitikum på centrala Södertörn, östra Mellansverige : Kvartärgeologiska undersökningar längs väg 73, Överfors - Västnora
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The aim with this study was to reconstruct the shore displacement on central Södertörn, eastern middle Sweden. The achieved curve is supposed to serve as a base for archaeological discussions regarding dating and settlement location.By determining the isolation ages of local bogs and fens at different altitudes, a new shore displacement curve was compiled. The thresholds of five ancient lakes (Borgbergetmossen 50.1 m a.s.l., Långmossen 45.3 m a.s.l., Millingsmossen 44.8 m a.s.l., Vimossen 43.0 m a.s.l., and Malmbergamossen 38.7 m a.s.l.) were levelled and their isolations were determined on the basis of lithology, diatom analysis, organic carbon analysis and AMS radiocarbon dating of terrestrial macrofossils.At about 6800 BC, the Litorina Sea shore laid at a level that is now uplifted to c. 50 m above sea level. The shore displacement was regressive during the early Litorina Sea, e.g. the isostatic uplift was greater than the eustatic sea level rise, but a transgressive Litorina stage (L1) stopped the process of land gaining between 6800–5950 BC. Analyses of cores from Borgbergetmossen indicate that the basin had begun to isolate from sea due to regression and that this process disrupted by an increase in water depth. The transgression is also observed as a layer of clay at Vimossen, indicating greater water depth. During the following regressive period, c. 5950–5600 BC, with a relative uplift of c. 13 mm/yr, Borgbergetmossen, Långmossen and Millingsmossen became isolated lakes. A second transgression (L2) is recorded in the following century, when gyttja clay and clay was accumulated in Vimossen and Malmbergamossen, respectively. After c. 5500 BC, the shore displacement shows a regressive trend at a rate of c. 6mm/yr. Malmbergamossen became isolated from the sea at c. 4500 BC. This basin is now uplifted to c. 39 m a.s.l.Comparison with archaeological data indicates that the nearby Mesolithic sites were established along the former shore lines. Even though the general trend of the shore displacement was regressive, the inhabitants continued to live at the sites long after direct contact with the shore had ceased. This is explained by the topographically pronounced fissure-valley landscape; long vertical distance does not result in long horizontal distance.We have used the chronological timing of L1 and L2 for correlation with periods of increased summer temperatures in western Fennoscandia. Melting of glaciers resulted in a eustatic sea level rise that neutralized the isostatic uplift.
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| 24. |
- Rosqvist, Gunhild C., et al.
(författare)
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Shifts in precipitation during the last millennium in northern Scandinavia from lacustrine isotope records
- 2013
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Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 66, s. 22-34
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Tidskriftsartikel (refereegranskat)abstract
- Here we present delta P-18(diatom) data from two high-latitude lakes; one has short residence time and a water isotopic composition (delta O-18(lake)) that fluctuate due to seasonal variations in precipitation and temperature, and the other has delta O-18(lake) that is influenced by longer lake water residence times and evaporation. The delta O-18(diatom) records reveal common responses to precipitation forcing over the past millennium. Relatively wet summers are inferred from delta O-18(diatom) between 1000 and 1080 AD, 1300 and 1440 AD, and during the early 19th century, coincided with periods of high cloud cover inferred from tree-ring carbon isotopes, and other data for high Arctic Oscillation index. While relatively dry summers with increasing influence of winter snow are indicated between 1600 and 1750 AD. The co-response between carbon isotopes in trees and oxygen isotopes in diatoms strengthens the relationship between cloud cover and precipitation and the hypothesis that these changes were the result of significant regional shifts in atmospheric circulation.
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| 25. |
- Viberg, Andreas, et al.
(författare)
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Archaeological prospection of a high altitude Neolithic site in the Arctic mountain tundra region of northern Sweden
- 2013
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Ingår i: Journal of Archaeological Science. - : Elsevier BV. - 0305-4403 .- 1095-9238. ; 40:6, s. 2579-2588
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Tidskriftsartikel (refereegranskat)abstract
- During the summer of 2008 archaeological excavations and geophysical prospection surveys were carried out in the mountain tundra region of north-eastern Sweden. The investigations focused on locating settlement remains connected with a Middle Neolithic tool production site discovered by archaeologists in 2001. Magnetic susceptibility surveys using the MS2D system by Bartington Instruments and an EM38 by Geonics measuring the Inphase component of the electromagnetic field were used for the prospection of measurable traces of anthropogenic activity and structures such as hearths and middens within the estimated settlement area. Soil samples for phosphate analysis were also collected and analysed using a field analysis method developed by Merck. The magnetic susceptibility measurements successfully located a waste heap containing fire-cracked stones and refuse from a seasonal settlement. The results of the survey were confirmed by subsequent archaeological excavations, which also revealed a piece of resin with the imprint of a human tooth. One additional piece of resin dated the site to 3340-3100 BC. The soil phosphate analysis showed slightly increased values over the central part of the site and over the heap of fire-cracked stones. Comparison between the MS2D and EM38 measurements revealed a weak impact of the bedrock on the results, indicating a potential for the applicability of magnetic surveys to this specific type of environment. Future geophysical archaeological prospection in the Swedish mountain tundra region could benefit from a combined approach using high-resolution magnetometry and magnetic susceptibility measurements.
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| 26. |
- Viberg, Andreas, 1981-, et al.
(författare)
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Archaeological Prospection of a High Altitude Neolithic Site in the Arctic Mountain Tundra Region of Northern Sweden
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Ingår i: Journal of Archaeological Science. - 0305-4403 .- 1095-9238.
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Tidskriftsartikel (refereegranskat)abstract
- The project Arctic Sweden initiated during the International Polar Year (2007-2008) was aimed at investigating aspects of the natural and cultural environment in this area. During the summer of 2008 archaeological excavations and geophysical prospection surveys were carried out in the mountain tundra region of north-western Sweden. The investigations focused on locating settlement remains connected with a Middle Neolithic tool production site discovered by archaeologists in 2001. Magnetic susceptibility surveys using the MS2D system by Bartington Instruments and an EM38 by Geonics measuring the Inphase component of the electromagnetic field were used for the prospection of measureable traces of anthropogenic activity and structures such as hearths and middens within the estimated settlement area. Soil samples for phosphate analysis were also collected and analysed using a field analysis method developed by Merck. The magnetic susceptibility measurements successfully located a waste heap containing fire-cracked stones and refuse from a seasonal settlement. The results of the survey were confirmed by subsequent archaeological excavations, which also revealed a piece of resin with the imprint of a human tooth. One additional piece of resin dated the site to 3340 to 3100 BC. The soil phosphate analysis showed slightly increased values over the central part of the site and over the heap of fire-cracked stones, suggesting the applicability of the method to a mountain tundra environment. Comparison between the MS2D and EM38 measurements revealed a weak impact of the bedrock on the results, indicating a potential for the applicability of magnetic surveys to this specific type of environment. Future geophysical archaeological prospection in the Swedish mountain tundra region could benefit from a combined approach using high-resolution magnetometry and magnetic susceptibility measurements.
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