| 1. |
- Helmens, Karin, et al.
(författare)
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Prolonged interglacial warmth during the Last Glacial in northern Europe
- 2021
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Ingår i: Boreas. - : John Wiley & Sons. - 0300-9483 .- 1502-3885. ; 50, s. 331-350
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Tidskriftsartikel (refereegranskat)abstract
- Few fossil-based environmental and climate records in northern Europe are dated to Marine Isotope Stage (MIS) 5a around 80 ka BP. We here present multiple environmental and climate proxies obtained froma lake sequence of MIS 5a age in the Sokli basin (northern Finland). Pollen/spores, plant macrofossils, NPPs (e.g. green algae), bryozoa, diatoms and chironomids allowed an exceptionally detailed reconstruction of aquatic and telmatic ecosystem successions related to the development of the Sokli Ice Lake and subsequent infilling of a relatively small and shallow lake confined to the Sokli basin. A regional vegetation development typical for the early half of an interglacial is recorded by the pollen, stomata and plant macrofossil data. Reconstructions of July temperatures based on pollen assemblages suffer from a large contribution of local pollen from the lake’s littoral zone. Summer temperatures reaching present-day values, inferred for the upper part of the lake sequence, however, agree with the establishment of pine-dominated boreal forest indicated by the plant fossil data. Habitat preferences also influence the climate record based onchironomids. Nevertheless, the climate optima of the predominant intermediate- to warm-water chironomid taxa suggest July temperatures exceeding present-day values by up to several degrees, in line with climate inferences from a variety of aquatic and wetland plant indicator species. The disequilibrium between regional vegetation development and warm, insolation-forced summers is also reported for Early Holocene records from northern Fennoscandia. The MIS 5a sequence is the last remaining fossil-bearing deposit in the late Quaternary basin infill at Sokli to be studied using multi-proxy evidence. A unique detailed climate record for MIS5 is now available for formerly glaciated northern Europe. Our studies indicate that interglacial conditions persisted into MIS 5a, in agreement with data for large parts of the European mainland, shortening the Last Glacial by some 50 ka to MIS 4-2.
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| 2. |
- Bouchal, Johannes M., 1979-, et al.
(författare)
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Middle Miocene climate of southwestern Anatolia from multiple botanical proxies
- 2018
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Ingår i: Climate of the Past Discussions. - Vienna : European Geosciences Union (EGU). - 1814-9340 .- 1814-9359 .- 1814-9332. ; 14, s. 1427-1440
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The middle Miocene climate transition (MMCT) was a phase of global cooling possibly linked to decreasing levels of atmospheric CO2. The MMCT coincided with the European Mammal Faunal Zone MN6. From this time, important biogeographic links between Anatolia and eastern Africa include the hominid Kenyapithecus. Vertebrate fossils suggested mixed open and forested landscapes under (sub)tropical seasonal climates for Anatolia. Here, we infer the palaeoclimate during the MMCT and the succeeding cooling phase for a middle Miocene (14.8–13.2 Ma) of an intramontane basin in southwestern Anatolia using three2palaeobotanical proxies: (i) Köppen signatures based on the nearest-living-relative principle. (ii) Leaf physiognomy analysed with the Climate Leaf Analysis Multivariate Program (CLAMP). (iii) Genus-level biogeographic affinities of fossil floras with modern regions. The three proxies reject tropical climates for the MMCT of southwestern Anatolia and instead infer warm temperate C climates. Köppen signatures reject summer-dry Cs climates but cannot discriminate between fully humid Cf and winter-dry Cw; CLAMP reconstructs Cf climate based on the low X3.wet/X3.dry ratio. Additionally, we assess whether the palaeobotanical record does resolve transitions from the warm Miocene Climatic Optimum (MCO, 16.8–14.7 Ma) into the MMCT (14.7–13.9 Ma), and a more pronounced cooling at 13.9–13.8 Ma, as reconstructed from benthic stable isotope data. For southwestern Anatolia, we find that arboreal taxa predominate in MCO floras (MN5), whereas in MMCT floras (MN6) abundances of arboreal and non-arboreal elements strongly fluctuate indicating higher structural complexity of the vegetation. Our data show a distinct pollen zone between MN6 and MN7+8 dominated by herbaceous taxa. The boundary MN6 and MN7+8, roughly corresponding to a first abrupt cooling at 13.9–13.8 Ma, possibly might be associated with this herb-rich pollen zone.
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| 3. |
- Zale, Rolf, 1954-, et al.
(författare)
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Growth of plants on the Late Weichselian ice-sheet during Greenland interstadial-1?
- 2018
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Ingår i: Quaternary Science Reviews. - : Elsevier. - 0277-3791 .- 1873-457X. ; 185, s. 222-229
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Tidskriftsartikel (refereegranskat)abstract
- Unglaciated forelands and summits protruding from ice-sheets are commonly portrayed as areas where plants first establish at the end of glacial cycles. But is this prevailing view of ice-free refugia too simplistic? Here, we present findings suggesting that surface debris supported plant communities far beyond the rim of the Late Weichselian Ice-sheet during Greenland interstadial 1 (GI-1 or Bolling-Altered interstadial). We base our interpretations upon findings from terrigenous sediments largely resembling 'plant-trash' deposits in North America (known to form as vegetation established on stagnant ice became buried along with glacial debris during the deglaciation). In our studied deposit, we found macrofossils (N = 10) overlapping with the deglaciation period of the area (9.5-10 cal kyr BP) as well as samples (N = 2) with ages ranging between 12.9 and 13.3 cal kyr BP. The latter ages indicate growth of at least graminoids during the GI-1 interstadial when the site was near the geographic center of the degrading ice-sheet. We suggest that exposure of englacial material during GI-1 created patches of supraglacial debris capable of supporting vascular plants three millennia before deglaciation. The composition and resilience of this early plant community remain uncertain. Yet, the younger group of macrofossils, in combination with pollen and ancient DNA analyses of inclusions, imply that shrubs (Salix sp., Betula sp. and Ericaceae sp) and even tree species (Larix) were present in the debris during the final deglaciation stage.
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| 4. |
- Faurby, Sören, 1981, et al.
(författare)
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CarniFOSS: A database of the body mass of fossil carnivores
- 2021
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Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 30:10, s. 1958-1964
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Tidskriftsartikel (refereegranskat)abstract
- Motivation Body mass is one of the most important determinants of animal ecology. Unlike other important traits it is also readily inferable from fossils and it is therefore one of the only traits that can be directly analysed and compared between fossil and contemporary communities. Despite this, no comprehensive database of the body mass of larger clades of extinct species exists. Analysis of fossils has therefore been restricted to small clades or to smaller, potentially biased, subsets of species. We here describe CarniFoss, an open-access database of body masses of all 1,322 extinct species of non-pinniped Carnivoramorpha and two related extinct groups of carnivorous mammals, Hyaenodonta and Oxyaenidae. Main types of variables contained We gathered lengths of teeth of fossil and extant species and body mass for extant species and a few of the best-known fossil species. Following this we estimated body mass for all species through phylogenetic imputation. Spatial location and grain Global, terrestrial. Time period and grain We collected data on all known species within the focal groups. The known species all lived in the Palaeogene, Neogene or Quaternary (i.e., the last 66 Myr). Major taxa and level of measurement We searched for data on reported tooth size of all described species of Carnivoramorpha (excluding pinnipeds) and selected extinct related groups (Hyaenodonta and Oxyaenidae). We combined this with measured body mass for all extant species and inferred body mass based on long-bones for selected extinct species, as well as a species-level phylogeny including all extant and extinct species in the group, and inferred the body mass for all species using phylogenetic imputation. Software format Data are provided as a series of .csv files, with all metadata in a separate PDF file.
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| 5. |
- Bouchal, Johannes M., 1979-
(författare)
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The middle Miocene palynofloras of the Salihpaşalar lignite mine (Yatağan Basin, southwest Anatolia): environmental characterisationand comparison with palynofloras from adjacent basins
- 2019
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Ingår i: Palaeobiodiversity and Palaeoenvironments. - Berlin : Springer Berlin/Heidelberg. - 1867-1594 .- 1867-1608. ; 99:4, s. 591-636
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Tidskriftsartikel (refereegranskat)abstract
- As the third part of an ongoing investigation of middle Miocene palynofloras in the Yatağan Basin (YB), southwestern Anatolia, thepalynofloras of the Salihpaşalar lignite mine in the main YB were studied. Seven types of algal spores, aplanospores/zygospores orcysts, six types of lycophyte and fern spores, 12 types of gymnosperm pollen and 90 types of angiosperm pollen were identified. Of atotal of ca. 140 plant taxa described from the YB, over 10% are confined to the Salihpaşalar assemblage. Differences between coevalpalynofloras of the Sekköy Member might reflect changing or prograding depositional environments. A number of rare accessorialtaxa reflect these local differences: Pilularia, Valeriana, Drosera and Persicaria aff. amphibia only occur at Salihpaşalar and aretypical of shallow water or temporary ponds associated with a lake shore. Apart from this, all the palynofloras, originating from thelignite seams and overlying limnic limestones (uppermost Turgut and Sekköy Member), of the YB are strongly indicative of extensivewoody vegetation with a dominance of diverse Fagaceae and Pinaceae. In addition, a list comparing the well-documented YBpalynomorphs to morphologically similar palynomorphs of published late early to middle Miocene plant assemblages of westernAnatolian was compiled. Such a comparison reveals that in many instances different taxon names have been used to denote the sametaxa. Hence, resolving these synonymies is a prerequisite of any meaningful comparison of palynofloras in the region.
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| 6. |
- Kadin, Martina, et al.
(författare)
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Linking demographic and food-web models to understand management trade-offs
- 2019
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 9:15, s. 8587-8600
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Tidskriftsartikel (refereegranskat)abstract
- Alternatives in ecosystem-based management often differ with respect to trade-offs between ecosystem values. Ecosystem or food-web models and demographic models are typically employed to evaluate alternatives, but the approaches are rarely integrated to uncover conflicts between values. We applied multistate models to a capture-recapture dataset on common guillemots Uria aalge breeding in the Baltic Sea to identify factors influencing survival. The estimated relationships were employed together with Ecopath-with-Ecosim food-web model simulations to project guillemot survival under six future scenarios incorporating climate change. The scenarios were based on management alternatives for eutrophication and cod fisheries, issues considered top priority for regional management, but without known direct effects on the guillemot population. Our demographic models identified prey quantity (abundance and biomass of sprat Sprattus sprattus) as the main factor influencing guillemot survival. Most scenarios resulted in projections of increased survival, in the near (2016-2040) and distant (2060-2085) future. However, in the scenario of reduced nutrient input and precautionary cod fishing, guillemot survival was projected to be lower in both future periods due to lower sprat stocks. Matrix population models suggested a substantial decline of the guillemot population in the near future, 24% per 10 years, and a smaller reduction, 1.1% per 10 years, in the distant future. To date, many stakeholders and Baltic Sea governments have supported reduced nutrient input and precautionary cod fishing and implementation is underway. Negative effects on nonfocal species have previously not been uncovered, but our results show that the scenario is likely to negatively impact the guillemot population. Linking model results allowed identifying trade-offs associated with management alternatives. This information is critical to thorough evaluation by decision-makers, but not easily obtained by food-web models or demographic models in isolation. Appropriate datasets are often available, making it feasible to apply a linked approach for better-informed decisions in ecosystem-based management.
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| 7. |
- Lundberg, Johannes, 1972-, et al.
(författare)
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Expedition Gobhologrottan 2012-2014
- 2014
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Ingår i: Grottan. - : Sveriges Speleologförbund. - 0345-4215. ; 49:2, s. 24-32
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Tidskriftsartikel (populärvet., debatt m.m.)
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