| 1. |
- Bergman, Jonas, et al.
(författare)
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When the River Began—The Formation of River Motala Ström and Human Presence in the Early Holocene, Sweden
- 2020
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 3:3
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Tidskriftsartikel (refereegranskat)abstract
- In conjunction with the extensive archaeological projects conducted at the current outlet of Sweden’s second largest lake, Lake Vättern, macrofossil, pollen and diatom records have been studied from 14C-dated lake and river sediments from River Motala Ström in Motala and Lake Boren. These investigations have revealed sedimentary evidence of the Yoldia Sea regression, the Ancient Lake Vättern transgression, and the following stepwise river formation process. Around 9000 cal BC, two small kettlehole basins at Strandvägen and Kanaljorden became isolated from the Baltic basin. As the ice sheet retreated further north, the isostatic uplift isolated the Vättern basin from the Baltic basin. Due to the uneven isostatic uplift, the basin tilted toward the south, and the Ancient Lake Vättern transgression started in Motala. The threshold in Motala at 92.5 m a.s.l. was reached around 7200 cal BC, and River Motala Ström was formed. 14C-dated diatom records from Lake Boren, and shoreline deposits in Motala, confirm this event. The water level in Lake Vättern initially fell around 1.5 m, and around 5800 cal BC, a second erosional event cut down the threshold to modern day level. At this time, the Late Mesolithic settlements in Motala were established and expanded.
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| 2. |
- Boeskorov, G G, et al.
(författare)
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The Preliminary Analysis of Cave Lion Cubs Panthera spelaea (Goldfuss, 1810) from the Permafrost of Siberia
- 2021
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 4:3
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Tidskriftsartikel (refereegranskat)abstract
- A preliminary description is presented of the well-preserved frozen mummies of two cubs of the extinct cave lion Panthera spelaea (finds of 2017–2018, Semyuelyakh River, Yakutia, eastern Siberia, Russia). The fossil lion cubs were found in close proximity, but they do not belong to the same litter, since their radiocarbon ages differ: the female (named ‘Sparta’) was dated to 27,962 ± 109 uncal years BP, and the male (named ‘Boris’) was dated to 43,448 ± 389 uncal years BP. The lion cubs have similar individual ages, 1–2 months. The general tone of the colour of the fur coat of Sparta is greyish to light brown, whereas, in Boris, the fur is generally lighter, greyish yellowish. It is, therefore, possible that light colouration prevailed with age in cave lions and was adaptive for northern snow-covered landscapes. The article discusses the results of computed tomography of cubs of the cave lion, the possible reasons for their death, and the peculiarities of their existence in the Siberian Arctic.
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| 3. |
- Capo, Eric, et al.
(författare)
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Lake sedimentary dna research on past terrestrial and aquatic biodiversity: Overview and recommendations
- 2021
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Ingår i: Quaternary. - : MDPI. - 2571-550X. ; 4:1
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Forskningsöversikt (refereegranskat)abstract
- The use of lake sedimentary DNA to track the long-term changes in both terrestrial and aquatic biota is a rapidly advancing field in paleoecological research. Although largely applied nowadays, knowledge gaps remain in this field and there is therefore still research to be conducted to ensure the reliability of the sedimentary DNA signal. Building on the most recent literature and seven original case studies, we synthesize the state-of-the-art analytical procedures for effective sampling, extraction, amplification, quantification and/or generation of DNA inventories from sedimentary ancient DNA (sedaDNA) via high-throughput sequencing technologies. We provide recommendations based on current knowledge and best practises.
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| 4. |
- Finné, Martin, et al.
(författare)
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Last Interglacial Climate in Northern Sweden-Insights from a Speleothem Record
- 2019
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 2:3
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Tidskriftsartikel (refereegranskat)abstract
- Continental records with absolute dates of the timing and progression of climatic conditions during the Last Interglacial (LIG) from northern Europe are rare. Speleothems from northern Europe have a large potential as archives for LIG environmental conditions since they were formed in sheltered environments and may be preserved beneath ice sheets. Here, we present delta C-13 and delta O-18 values from speleothem Kf-21, from Korallgrottan in Jamtland (northwest Sweden). Kf-21 is dated with five MC-ICPMS U-Th dates with errors smaller than similar to 1 ka. Kf-21 started forming at similar to 130.2 ka and the main growth phase with relatively constant growth rates lasted from 127.3 ka to 124.4 ka, after which calcite formation ceased. Both delta C-13 and delta O-18 show rapid shifts but also trends, with a range of values within their Holocene counterparts from Korallgrottan. Our results indicate an early onset of the LIG in northern Europe with ice-free conditions at similar to 130 ka. Higher growth rates combined with more negative delta O-18 values between similar to 127.3 and 126.8 ka, interpreted here as warmer and more humid conditions, as well as indications of a millennial-scale cold spell centered at 126.2 ka, resemble findings from speleothem records from other parts of Europe, highlighting that these were regional scale climatic patterns.
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| 5. |
- Fitzsimmons, Kathryn E., et al.
(författare)
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Luminescence sensitivity of rhine valley loess : Indicators of source variability?
- 2022
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 5:1
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Tidskriftsartikel (refereegranskat)abstract
- Loess provides a valuable terrestrial record of past environmental conditions, including the dynamics and trajectories of air mass circulation responsible for dust transport. Here we explore variations in the luminescence sensitivity characteristics of sedimentary quartz and feldspar as possible tools for identifying changes in source down a loess-palaeosol sequence (LPS). Luminescence sensitivity is a rapidly measurable index which is the product of interplay between source lithology and the history of the quartz or feldspar clasts. Variations in sensitivity of down profile may therefore reflect changes in sediment provenance as well as other factors such as weathering through pedogenesis. We undertake an empirical investigation of the luminescence sensitivity of quartz and feldspar from different grain-size fractions from the Schwalbenberg LPS in the German Rhine valley. We compare samples from a 30 m core spanning the last full glacial cycle with samples of oxygen isotope stage (OIS) 3–2 age exposed within nearby profile. We find an overall inverse relationship between quartz and feldspar sensitivity, as well as variability in sensitivity between different quartz grain sizes. Statistical analyses yield a significant correlation between IR50 sensitivity from unprocessed sediments and clay content, and feldspar sensitivity and Si/Al ratios down the core. Since Si/Al ratios may indicate changes in provenance, the latter correlation suggests that IR50 measurements on unprocessed samples may be used to provide a reliable, rapid scan of source variability over millennial timescales.
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| 6. |
- Hansson, Anton, et al.
(författare)
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Shoreline Displacement, Coastal Environments and Human Subsistence in the Hanö Bay Region during The Mesolithic
- 2019
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 2:1
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Tidskriftsartikel (refereegranskat)abstract
- Southern Scandinavia experienced significant environmental changes during the early Holocene. Shoreline displacement reconstructions and results from several zooarchaeological studies were used to describe the environmental changes and the associated human subsistence and settlement development in the Hanö Bay region of southern Sweden during the Mesolithic. GIS-based palaeogeographic reconstructions building on shoreline displacement records from eastern Skåne and western Blekinge together with a sediment sequence from an infilled coastal lake were used to describe the environmental changes during five key periods. The results show a rapid transformation of the coastal landscape during the Mesolithic. During this time, the investigated coastal settlements indicate a shift towards a more sedentary lifestyle and a subsistence focused on large-scale freshwater fishing. The development of permanent settlements coincided with an extended period of coastline stability and the development of rich coastal environments in a more closed forest vegetation. This study provides a regional synthesis of the shoreline displacement, coastal landscape dynamics and settlement development during the Mesolithic. It also demonstrates a new way of combining zooarchaeological and palaeoecological approaches, which can produce multi-faceted and highly resolved palaeoenvironmental reconstructions in a wide range of settings.
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| 7. |
- Labuhn, Inga, et al.
(författare)
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Holocene Hydroclimate Variability in Central Scandinavia Inferred from Flood Layers in Contourite Drift Deposits in Lake Storsjön
- 2018
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 1:1
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Tidskriftsartikel (refereegranskat)abstract
- Despite the societal importance of extreme hydroclimate events, few palaeoenvironmental studies of Scandinavian lake sediments have investigated flood occurrences. Here we present a flood history based on lithological, geochemical and mineral magnetic records of a Holocene sediment sequence collected from contourite drift deposits in Lake Storsjön (63.12° N, 14.37° E). After the last deglaciation, the lake began to form around 9800 cal yr BP, but glacial activity persisted in the catchment for ~250 years. Element concentrations and mineral magnetic properties of the sediments indicate relatively stable sedimentation conditions during the Holocene. However, human impact in the form of expanding agriculture is evident from about 1100 cal yr BP, and intensified in the 20th century. Black layers containing iron sulphide appear irregularly throughout the sequence. The increased influx of organic matter during flood events led to decomposition and oxygen consumption, and eventually to anoxic conditions in the interstitial water preserving these layers. Elevated frequencies of black layer occurrence between 3600 and 1800 cal yr BP reflect vegetation changes in the catchment as well as large-scale climatic change. Soil erosion during snowmelt flood events increased with a tree line descent since the onset of the neoglacial period (~4000 cal yr BP). The peak in black layer occurrence coincides with a prominent solar minimum ~2600 cal yr BP, which may have accentuated the observed pattern due to the prevalence of a negative NAO index, a longer snow accumulation period and consequently stronger snowmelt floods
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| 8. |
- Li, H. H., et al.
(författare)
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Influences of West Pacific Sea Surface Temperature on Covarying Eurasian Droughts Since the Little Ice Age
- 2020
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 3:2
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Tidskriftsartikel (refereegranskat)abstract
- The Western Pacific Warm Pool (WP), with the highest sea surface temperature (SST) in the world, has strong impacts on the drought variations in Eurasia. However, since the little ice age (1250-1850, LIA), the co-climatic drought pattern due to WP warming in Eurasia remains unclear. This is a long-term warming background for the current warming period (CWP). In this paper, we use both instrumental data and 1625 tree-ring width records from Eurasia to investigate the drought patterns in both modern and historical periods. This study revealed two seesaw precipitation patterns, namely the Central Asia-Mongolia (CAMO) and Northern Europe-Southern Europe (NESE) patterns. When the Western Pacific Warm Pool sea surface temperature (WPSST) is high, precipitation increases in Central Asia and Northern Europe, and decreases in Mongolia and southern Europe. When the positive (negative) phase event of the El Nino-Southern Oscillation (ENSO) occurs, the WPSST is reduced (increased), and the decreases (increases) of precipitation in Central Asia and Northern Europe and the increases (decreases) in precipitation in Mongolia and southern Europe are more obvious. The CAMO dipole has been strengthened since the LIA. The CAMO dipole is positively correlated with solar radiation and Northern Hemisphere temperature, and negatively correlated with Pacific decadal oscillations (PDO).
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| 9. |
- Parducci, Laura, 1965-
(författare)
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Quaternary DNA : A Multidisciplinary Research Field
- 2019
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 2:4
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Forskningsöversikt (refereegranskat)abstract
- The purpose of this Milankovitch review is to explain the significance of Quaternary DNA studies and the importance of the recent methodological advances that have enabled the study of late Quaternary remains in more detail, and the testing of new assumptions in evolutionary biology and phylogeography to reconstruct the past. The topic is wide, and this review is not intended to be an exhaustive account of all the aDNA work performed in the last three decades on late-Quaternary remains. Instead, it is a selection of relevant studies aimed at illustrating how aDNA has been used to reconstruct not only environments of the past, but also the history of many species including our own.
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| 10. |
- Power, Katherine, et al.
(författare)
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The Role of El Niño in Driving Drought Conditions over the Last 2000 Years in Thailand
- 2020
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Ingår i: Quaternary. - : MDPI AG. - 2571-550X. ; 3:2
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Tidskriftsartikel (refereegranskat)abstract
- Irregular climate events frequently occur in Southeast Asia due to the numerous climate patterns combining. Thailand sits at the confluence of these interactions, and consequently experiences major hydrological events, such as droughts. Proxy data, speleothem records, lake sediment sequences and tree ring chronologies were used to reconstruct paleo drought conditions. These trends were compared with modelled and historic El Nino Southern Oscillation (ENSO) data to assess if the ENSO climate phenomena is causing droughts in Thailand. Drought periods were found to occur both during El Nino events and ENSO neutral conditions. This indicates droughts are not a product of one climate pattern, but likely the result of numerous patterns interacting. There is uncertainty regarding how climate patterns will evolve under climate change, but changes in amplitude and variability could potentially lead to more frequent and wider reaching hydrological disasters. It is vital that policies are implemented to cope with the resulting social and economic repercussions, including diversification of crops and reorganisation of water consumption behaviour in Thailand.
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