1. |
- Björkman, Leif, et al.
(author)
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Late-Glacial and Holocene forest dynamics at Steregoiu in the Gutaiului Mountains, Northwest Romania
- 2003
-
In: Review of Palaeobotany and Palynology. - 0034-6667 .- 1879-0615. ; 124:1-2, s. 79-79
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Journal article (peer-reviewed)abstract
- Pollen analyses and AMS C-14 measurements were performed on lacustrine sediments and peat deposits from the former crater lake Steregoiu in a mid-altitude area in the Gutaiului Mountains in NW Romania in order to provide a detailed reconstruction of the vegetational development of the area during the Late-Glacial and Holocene. The bottom sediments are siliciclastic and were deposited probably during the Full Glacial, which is characterised by open patchy vegetation consisting of a mosaic of shrubs, herbs, and ungrown grounds. Around 14 700 cal yr BP an open Pinus-Betula forest expanded, at the same time as organic-rich lake sediments started to be deposited. This change was likely a response to the first deglacial warming phase at the beginning of the Boiling period, or GI-1e, in the GRIP event stratigraphy. Between 13 750 and 12 950 cal yr BP an open forest dominated by Betula, Picea, Pinus, and Ulmus developed in the area. The forest composition implies rather warm climatic conditions, which may correspond to the Allerod, or GI-1c-GI-1a. Around 12950 cal yr BP the forest retracted, and at 12600 cal yr BP open patchy vegetation became re-established. These changes imply a return to significantly colder conditions, which may correspond to the Younger Dryas, or GS-1. At 11500 cal yr BP Betula, Pinus, and Alnus quickly responded to the temperature rise, characterising the beginning of the Holocene. Within a few hundred years, around 11300 cal yr BP, Ulmus and Picea became re-established and a mixed forest type expanded. Quercus, Tilia, and Fraxinus likely arrived at around 10 750 cal yr BP, and from about this time Betula, and Pinus started to diminish. Around 10 500 cal yr BP a dense mixed forest dominated by Ulmus, Picea, Quercus, Tilia, and Fraxinus had developed in the area. Corylus probably became locally established around 10 500 cal yr BP, but it did not expand until 10 200 cal yr BP. Tilia and Fraxinus were locally important until 8600 cal yr BP, when Picea gained renewed importance and the lake became completely overgrown. Picea was probably an important constituent in the carr forest at the site as well as in the upland forest. Around 4800 cal yr BP Fagus and Carpinus became important in the local stand, apparently without any major disturbance of the forest. Until around 3400 cal yr BP the forest was highly diverse, but when Fagus eventually expanded, Ulmus, Tilia, Picea, and Corylus diminished. From about 2200 cal yr BP onwards Fagus has been the local forest dominant, but some Quercus and Carpinus individuals have been present as well. Pollen evidence for human influence on the local vegetation is comparatively scant. The area may have been used for forest grazing from about 1050 cal yr BP, but the grazing pressure was probably low until ca. 300 cal yr BP. (C) 2002 Elsevier Science B.V. All rights reserved.
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2. |
- Lindström, Sofie
(author)
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Lunnomidinium scaniense Lindstrom, gen. et sp nov., a new suessiacean dinoflagellate cyst from the Rhaetian of Scania, southern Sweden
- 2002
-
In: Review of Palaeobotany and Palynology. - 0034-6667. ; 120:3-4, s. 247-261
-
Journal article (peer-reviewed)abstract
- The dinoflagellate cyst Lunnomidinium scaniense gen. et sp. nov. is present in the lower part of a thin sequence of Rhaetian sedimentary rocks exposed in the Lunnom Coal and Clay Pit in NW Scania, southern Sweden! It occurs in diverse, Rhaetian palynomorph assemblages, dominated by spores and pollen, but with rare specimens of the dinoflagellate cysts Rhaetogonyaulax rhaetica (Sarjeant) Loeblich and Loeblich 1968, Shublikodinium sp. and Beaumontella? caminuspina (Wall) Below 1987. Lunnomidinium scaniense is characterized by an epicystal {tAtItP} archeopyle, a large number of paraplates arranged in seven or eight latitudinal series, and intratabular ornamentation in some but not all of the paraplate series. Thus, L. scaniense is assignable to the family Suessiaceae. Lunnomidinium scaniense can be subdivided into two different morphological varieties, based on the autophragm ornamentation and cyst size.
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3. |
- Gaillard, Marie-Jose, et al.
(author)
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Application of modern pollen/land-use relationships to the interpretation of pollen diagrams - reconstructions of land-use history in South Sweden 3000-0 BP
- 1994
-
In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667 .- 1879-0615. ; 82:1-2, s. 47-73
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Journal article (peer-reviewed)abstract
- A modem pollen/land-use data-set of 124 surface samples (moss polsters) from different vegetation and land-use types in south Sweden is presented. The samples are from non-fertilized grazed areas, burned and grazed heaths, traditionally managed fodder-producing meadows and cultivated fields, and deciduous forests. Twenty nine environmental (e.g. management type, soil chemistry) variables are available for the 124 samples. Patterns of modern local pollen variation in relation to these environmental variables are explored by canonical correspondence analysis (CCA) and tested by associated statistical procedures. The modem data-set is used to aid interpretation of extra-local pollen sequences from two small lakes and one mire in south Sweden, using CCA as a means of comparing modem and fossil spectra. The resulting land-use reconstructions are compared to earlier interpretations of the same pollen-stratigraphical data using the more traditional ''indicator-species'' approach. Emphasis is placed on the history of mowing and grazing in south Sweden as an example of the potential uses of the comparative approach for interpretating fossil pollen data in terms of past land-use.
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4. |
- Harland, Rex, et al.
(author)
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A high-resolution dinoflagellate cyst record from latest Holocene sediments in Koljo Fjord, Sweden
- 2004
-
In: Review of Palaeobotany and Palynology. - 0034-6667. ; 128:1-2, s. 119-141
-
Journal article (peer-reviewed)abstract
- A high-resolution dinoflagellate cyst record is detailed for the very latest Holocene sediments preserved in a silled fjord from western Sweden. Koljo Fjord is characterised by brackish water conditions together with intermittent deep-water renewal and oxygen depletion. The data provide information derived from the phytoplankton populations living in the surface waters, including possible changes to the nutrient availability and salinity regimes using an actualistic ecological approach. The cyst record provides evidence that the dinoflagellate populations within the surface waters of the fjord over the last 155 years or so have fluctuated markedly. The dinoflagellate cyst record from Core KG1A demonstrates a 10-fold increase in both total cyst numbers and Lingulodinium polyedrum since c. 1938, and a shift from assemblages with high Pentapharsodinium dalei to those with high L. polyedrum and Protoceratium reticulatum from about 1980. These fluctuations are singly and/or collectively indicative of possible cultural changes within the fjord; the effects of the North Atlantic Oscillation on both deep-water renewal and seasonality; nutrient enhancement (eutrophication?); and increased water column stability. (C) 2003 Elsevier B.V. All rights reserved.
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5. |
- Harland, Rex, et al.
(author)
-
The seasonal occurrence of dinoflagellate cysts in surface sediments from Koljo Fjord, west coast of Sweden - a note
- 2004
-
In: Review of Palaeobotany and Palynology. - 0034-6667. ; 128:1-2, s. 107-117
-
Journal article (peer-reviewed)abstract
- The opportunistic collection of the flocculent layer, over the spring to late summer seasons, has provided information on the seasonal dinoflagellate cyst sedimentation in Koljo Fjord, on the west coast of Sweden. The dinoflagellate cyst assemblages within the flocculent layer can be both diverse and contain many cysts. The cyst assemblages do not remain constant over time but demonstrate seasonality. Our very limited dataset of six samples suggests that the spring bloom is characterised by round, brown Protoperidinium cysts together with subsidiary Pentapharsodinium dalei and Protoperidinium conicum. The early summer assemblage differs in containing higher proportions of P. dalei with fewer round, brown Protoperidinium cysts together with relatively minor amounts of Lingulodinium polyedrum and Polykrikos schwartzii. The late summer cyst flora is co-dominated by Lingulodinium polyedrum and round, brown Protoperidinium cysts, together with minor amounts of P. dalei and Spiniferites spp. including Spiniferites bentorii. Cyst production within the different species occurs at times of the year when the surface water conditions within the fjord are suitable. This probably reflects, all or in part, the stability of the upper water column, the relative availability of nutrients and the overall phytoplankton productivity. (C) 2004 Elsevier B.V. All rights reserved.
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6. |
- Adroit, Benjamin, et al.
(author)
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Are morphological characteristics of Parrotia (Hamamelidaceae) pollen species diagnostic?
- 2022
-
In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier BV. - 0034-6667 .- 1879-0615. ; 307, s. 104776-104776
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Journal article (peer-reviewed)abstract
- Parrotia persica is one of the most notable endemic relict tree species growing in the Hyrcanian forest at the southern Caspian Sea. The recent discovery of sibling species Parrotia subaequalis, occurring in the temperate forests of south-eastern China, offers the opportunity to compare their morphology and ecological preferences and to dig deeper into the paleophytogeographic history of the genus from a perspective. Since pollen morphology of these species would be essential to unravel the origin and evolution of these Arcto-Tertiary species, the present study aimed to investigate whether it is possible to segregate pollen from these two species. Therefore, a detailed combined light- and scanning electron microscopy-based pollen-analysis of each taxon was conducted, the pollen was described, measured, and compared using statistical approaches and principal component analyses to establish unbiased results. The correlation-based principal component analysis achieved for each species shows an overall good superposition of pollen grains measured in equatorial and polar views in the first principal plane, revealing that the P. persica pollen is morphometrically as homogeneous as that of P. subaequalis. Then, the significant difference, mainly driven by lumen density, has been highlighted between the two species. Ultimately, the cross-validation of the resulting two-species linear discriminants classifier shows that based upon this reference dataset, (sub)fossil pollen grain can now be confidently assigned to either of the two species with an 85.8% correct-assignment rate. This opens new doors in the affiliation of fossil Parrotia pollen and suggests that previous pollen records need to be revised.
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7. |
- Bergman, Jonas, et al.
(author)
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Deglacial vegetation succession and Holocene tree-limit dynamics in the Scandes Mountains, west-central Sweden: stratigraphic data compared to megafossil evidence
- 2005
-
In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 134:3-4, s. 129-151
-
Research review (peer-reviewed)abstract
- High-resolution records of plant macrofossils, magnetic susceptibility, and total carbon content, complemented by pollen data, were obtained from a postglacial lake sediment sequence at alpine Lake Stentjarn (987 m a.s.l.), in west-central Sweden. Holocene vegetational and environmental changes were reconstructed from the data, with particular emphasis on the deglacial establishment of terrestrial vegetation and subsequent tree-limit dynamics. A short-lived pioneer flora with Geum rivale, Dryas octopetala, Empetrum nigrum, Ledum palustre, Saxifraga sp., Salix spp., and Oxyria digyna established locally following deglaciation at c. 10,500 cat year BP. The pioneer flora was out-competed by establishing Betula pubescens and grasses at c. 10,300 cat year BP. Subsequent local expansions of B. pubescens at c. 9800 cat year BP and Pinus sylvestris at c. 9200 cal year BP were followed by a temporary retraction of the birch tree-limit and a permanent retreat of pine between 8500 and 8000 cat year BP, accompanied by declining aquatic productivity and increasing catchment erosion. A gradual decrease in forest density initiated at c. 6000 cat year BP led to a retreat of the birch tree-limit from the lake catchment at c. 3500 cat year BP, followed by persistence of scattered trees until c. 2000 cat year BP. A mosaic heath vegetation dominated by Empetrum nigrum and Betula nana developed at c, 3500 cat year BP. Comparison of the stratigraphic data from Lake Stenljiirn with records of radiocarbon-dated subfossil wood remains (megafossils) obtained from adjacent areas during recent decades revealed a high level of consistency of the inferred tree-limit variations for P. sylvestris, B. pubescens, and Alnus incana. Chronological control was established by radiocarbon dating of terrestrial macrofossils and geochemical identification of a tephra horizon originating from the Icelandic Askja- 1875 eruption.
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8. |
- Bomfleur, Benjamin, 1979-, et al.
(author)
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From the Transantarctic Basin to the Ferrar Large Igneous Province: New palynostratigraphic age constraints for Triassic-Jurassic sedimentation and magmatism in East Antarctica
- 2014
-
In: Review of Palaeobotany and Palynology. - : Elsevier. - 0034-6667 .- 1879-0615. ; 207, s. 18-37
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Journal article (peer-reviewed)abstract
- We present new palynological data from the Transantarctic Mountains that clarify the timing of sedimentary and magmatic processes in the transition from continental deposition of the Beacon Supergroup to emplacement of the Ferrar Large Igneous Province. Samples were collected from twenty-three Triassic and Jurassic sections in the southern area of north Victoria Land (NVL), East Antarctica. Recovered palynomorph assemblages are correlated with the widely used, although informal palynostratigraphic framework established for eastern Australia by Price. The associated Late Triassic–earliest Jurassic zone, APT5, is modified here with a proposed new subdivision: Lower APT5 (“APT5L”; middle–late Norian), Middle APT5 (“APT5M”; Rhaetian), and Upper APT5 (“APT5U”;Hettangian–earliest Sinemurian). We further propose a modification unifying the relevant formal eastern Australian and New Zealand palynostratigraphic zones, with a new Polycingulatisporites crenulatus Association Zone (new zonal status) that includes the P. crenulatus Association Subzone (new subzone; equivalent toAPT5L) and the following Foveosporites moretonensis Association Subzone (new subzonal status; equivalent to APT5M). Our palynostratigraphic dating of the NVL assemblages demonstrates that the onset of sedimentation was diachronous in this part of the Transantarctic Basin, ranging from at least the Rhaetian to, in places, early Sinemurian. By lack of evidence for rocks containing APT5U assemblages and by analogy with the few coeval sections in Australia, we infer that the Hettangian interval in NVL is probably consumed by unconformity. Depositionof ashes from distal silicic volcanism commenced in the early Sinemurian and reached a peak phase beginning in middle Pliensbachian (ca 187Ma), coinciding with the first major magmatic interval of the silicic Chon Aike Province in Patagonia and West Antarctica. Two major episodes of phreatomagmatic activity, driven by shallow-level sill intrusion into sandstone aquifers, occurred during the middle Pliensbachian and during the late Pliensbachian–early Toarcian. The latter episode was closely followed by the first pillow extrusion and local lava effusion. Contrary to some previous studies, we further conclude that all available palynological evidence is compatible with a short-lived emplacement of the plateau-forming Kirkpatrick Basalt at around 180 Ma during the early Toarcian.
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9. |
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10. |
- Bouchal, Johannes M., 1979-, et al.
(author)
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Miocene palynofloras of the Tınaz lignite mine, Muğla, southwest Anatolia: taxonomy, palaeoecology and local vegetation change
- 2017
-
In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 243, s. 1-36
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Journal article (peer-reviewed)abstract
- Middle Miocene deposits exposed at the Tınaz lignite mine, Yatağan Basin, Muğla, southwestern Turkey, were palynologically investigated. The Tınaz lignite mine section belongs to the Eskihisar Formation. The lignite seam at the base of the section represents the uppermost part of the Turgut Member. Above, c. 65 m of clayey siltstone, limestone, and marls represent the Sekköy Member. Nine spores, zygospores and cysts of fungi and algae, seven moss and fern spores, 12 gymnosperm pollen types, and more than 80 angiosperm pollen taxa were recovered from the Tınaz lignite mine section. Three pollen zones were recognized, of which pollen zone 1 corresponds to the formation of the main lignite seam and reflects the change from a fluviatile to a lacustrine depositional setting. Pollen zones 2 and 3 and a transitional zone 2-3 reflect different stages of lake development and a shift in local vegetation from forested (pollen zones 1 and 2) to more open (transitional zone 2-3, zone 3). Interpreting changes in regional vegetation from pollen zones 1 to 3 is not straightforward as changes in the pollen spectra may be affected by changing contributions of airborne and water transported pollen and spores to the observed palynoassemblages. Age inference for the Tınaz lignite mine section has been complicated by the absence of datable ash layers, associated mammal faunas, or marine sediments. However, pollen zone 3 shares key features with the pollen spectrum recovered from the nearby mammal site Yenieskihisar (upper part of Sekköy Member) for which an age of 12.5-11.2 Ma has been suggested, and to the youngest pollen zone recovered from the mammal locality Çatakbağyaka, 10 km south of Tınaz, that probably represents mammal zone MN7/8 instead of MN5 or MN6 as previously suggested. In contrast, pollen zones 1 and 2 are fairly similar to the basal parts of the Çatakbağyaka pollen flora (uppermost parts of Turgut Member, basalmost parts of Sekköy Member). Furthermore, new mammal data from the Yatağan basin suggest that the layers below pollen zone 1 are MN4/5, and that carnivores cooccuring with pollen zone 1 in the main lignite seam of Eskihisar probably belong to MN6. Hence, a Langhian to Serravallian age can be inferred for pollen zones 1 and 2 of the Tınaz lignite mine section, and a late Serravallian age for pollen zone 3. Palaeobiogeographic relationships of the palynofloras are generally northern hemispheric, with many north temperate tree taxa showing modern disjunctions East Asia- NorthAmerica (Tsuga, Carya), East Asia- western Eurasia (Zelkova), East Asia- North America- western Eurasia (Liquidambar), or restricted to East Asia (Cathaya, Eucommia) or North America (Decodon). A few taxa belong to extinct lineages that have complex biogeographic patterns (Engelhardioideae, Cedrelospermum). The presence of Picrasma (Simaroubaceae) in the lower lignite layers of pollen zone 1 is remarkable, as the botanical affinities with the enigmatic flower Chaneya present in early to middle Miocene deposits of Turkey and Central Europe have recently been shown to be with Picrasma.
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11. |
- Cavalcante, Larissa Lopes, et al.
(author)
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Analysis of fossil plant cuticles using vibrational spectroscopy: A new preparation protocol
- 2023
-
In: Review of Palaeobotany and Palynology. - : Elsevier. - 0034-6667 .- 1879-0615. ; 316
-
Journal article (peer-reviewed)abstract
- Analyses for organic “fingerprints” on fossilized plant cuticles and pollen hold valuable chemotaxonomic and palaeoclimatic information, and are thus becoming more utilized by palaeobotanists. Plant cuticle and pollen composition are generally analyzed after standard treatments with several chemical reagents for mineral and mesophyll removal. However, the potential alterations on the fossil composition caused by the different cleaning reagents used are still poorly understood. We tested the effects of commonly used palaeobotanical processing methods on the spectra of fossilized cuticles from successions of Late Triassic to Early Jurassic age, including the gymnosperms Lepidopteris, Ginkgoites, Podozamites, Ptilozamites and Pterophyllum astartense. Our study shows that standard chemical processing caused chemical alterations that might lead to erroneous interpretation of the infrared (IR) spectra. The difference in pH caused by HCl induces changes in the proportion between the two bands at ~1720 and 1600 cm 1 (carboxylate and C-C stretch of aromatic compounds) indicating that the band at ~1610 cm 1 at least partially corresponds to carboxylate instead of C-C stretch of aromatic compounds. Interestingly, despite being used in high concentration, HF did not cause changes in the chemical composition of the cuticles. The most alarming changes were caused by the use of Schulze ’s solution, which resulted in the addition of both NO2 and (O)NO2 compounds in the cuticle. Consequently, a new protocol using H2CO3, HF, and H2O2 for preparing fossil plant cuticles aimed for chemical analyses is proposed, which provides an effective substitute to the conventional methods. In particular, a less aggressive and more sustainable alternative to Schulze’s solution is shown to be hydrogen peroxide, which causes only minor alteration of the fossil cuticle ’s chemical composition. Future work should carefully follow protocols, having in mind the impacts of different solutions used to treat leaves and other palaeobotanical material such as palynomorphs with aims to enable the direct comparison of spectra obtained in different studies.
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12. |
- Daly, Robert J., et al.
(author)
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A palynological study of an extinct arctic ecosystem from the Palaeocene of Northern Alaska
- 2011
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 166:1-2, s. 107-116
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Journal article (peer-reviewed)abstract
- The Palaeocene arctic supported a vegetation type quite distinct from the tundra and polar desert of today. Here we demonstrate, through the palynological record, the structure of this extinct vegetation and its dynamics over this period. The Late Palaeocene coal-bearing units of the Sagwon Bluffs on Alaska's North Slope (present latitude 69 degrees N) are predominantly fine-grained, non-marine and rich in palynomorph-bearing sediments. From the analysed palynological assemblage we were able to demonstrate, using 'Detrended Correspondence Analysis' (DCA) and 'Fuzzy c-Means Cluster Analysis' (FCM), 1) a complex heterogeneous ecosystem, 2) its major successional states, and 3) its development over an extended period. The climax state of the floodplain was dominated by flood-tolerant, deciduous conifers such as Metasequoia. A more heterogeneous mid-successional assemblage is represented by angiosperm and gymnosperm co-dominance with an angiosperm dominance of Corylus, while early-successional ecological groups, dominated by ferns and bryophytes, are considered to represent riparian and post-disturbance niches. The structure of this vegetation does not remain static over the course of the stratigraphic interval represented. We observe a particularly dramatic ecological change for instance, following the deposition of a large conglomeratic unit. It is hypothesized that this corresponds to altered drainage and/or precipitation on the North Slope. The vegetation examined herein shows marked similarities to that of other palaeobotanical studies from various sites of similar age at high northern latitudes. It is hence considered to represent an extensive and long-lived circumpolar arctic biome. (C) 2011 Elsevier B.V. All rights reserved.
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13. |
- Decombeix, Anne-Laure, et al.
(author)
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Early Carboniferous lignophyte tree diversity in Australia: Woods fromthe Drummond and Yarrol basins, Queensland
- 2019
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In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 263, s. 47-64
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Journal article (peer-reviewed)abstract
- Early Carboniferous (Mississippian) permineralized woods from Australia with multiseriate rays have been customarily assigned or compared to the European genus Pitus, despite the absence of information on their primary vascular anatomy. In the context of continuing work on the diversity of Late Devonian andMississippian floras of Gondwana, we studied new silicified woods with secondary xylem similar to that of Pitus (multiseriate rays, araucarioid radial pitting) from two sedimentary basins of Queensland, Australia. In the Drummond Basin, three morphotypes of wood of Viséan age can be distinguished based on ray size in tangential section. Although this variation is similar to that observed between the various European species of Pitus, information on the primary vascular anatomy of the trees provided by three incomplete specimens excludes an affinity with Pitus for at least two taxa. In the Yarrol Basin, two well-preserved late Viséan trunks also have characters similar to Pitus but can be distinguished from that genus and other previously described Mississippian trees, in particular by the anatomy of their primary vascular system and departing leaf traces. They are assigned to a new genus, Ninsaria. Collectively, the new specimens from Queensland show that wood traditionally referred to “Pitus” from Australia actually belongs to several other types of trees that are not known from Europe or North America, indicating probable floristic provincialism between the Northern and Southern hemisphere floras at this time. These new fossils corroborate the existence of a global Mississippian diversification of (pro)gymnosperm trees already noted in Laurussia. They also indicate that the Mississippian floras of Australia were more diverse and complex than traditionally inferred.
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14. |
- Decombeix, Anne-Laure, et al.
(author)
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New data on the anatomy and systematic affinities of corystosperm wood from the Triassic of Antarctica
- 2014
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In: Review of Palaeobotany and Palynology. - : Elsevier. - 0034-6667 .- 1879-0615. ; 203:1, s. 22-34
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Journal article (peer-reviewed)abstract
- Anatomically preserved trunks and young stems of corystosperm seed ferns are described from the Triassic of Fremouw Peak, Beardmore Glacier area, Antarctica. Based on characters of the primary and secondary vascular system, these new specimens are assigned to Kykloxylon, a genus that was established based on young stems with attached Dicroidium leaf bases. The largest specimens illustrate how some secondary growth characters, such as unequal cambial activity, appeared during later development, which enables a better comparison of Kykloxylon with trunks assigned to other corystosperm genera. Jeffersonioxylon from the Gordon Valley, Antarctica, and Cuneumxylon from South America show strong similarities with the newly described larger Kykloxylon trunks from Fremouw Peak, and might be considered congeneric. Our results provide further support for the presence of two anatomically and morphologically distinct kinds of Dicroidium-bearing trees in the Triassic vegetation of Gondwana, one with a palm-like habit and Rhexoxylon stems and the other with a more Ginkgo-like habit and Kykloxylon/Cuneumxylon-type stems
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15. |
- Denk, Thomas, et al.
(author)
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Catalogue of revised and new plant macrofossils from the Aquitanian-Burdigalian of Soma (W Turkey) – Biogeographic and palaeoclimatic implications
- 2022
-
In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 296, s. 1-42
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Journal article (peer-reviewed)abstract
- The position of Turkey between Europe and Asia makes this region interesting for palaeobotanical investigations. We investigated plant macrofossils from early Miocene deposits of W Turkey (Soma, Manisa) and compiled a catalogue of revised and new plant taxa. We documented 100 fossil-taxa, of which several are new for Turkey (Mahonia aff. pseudosimplex, Ziziphus paradisiaca, Comptonia longirostris, Carya denticulata, Viscum, Fatsia, Pungiphyllum cruciatum). Some previous records are rejected (e.g. Apocynophyllum, Cassia, Castanea, Ficus, Illicium, Liriodendron, Vaccinium). Using modern ecology and taphonomy, we reconstructed palaeoenvironments. We found evidence for a belt of drier, more open habitats with cycads, Dracaena, Mahonia, Smilax miohavanensis, and others. Other vegetation units comprise swamp and riparian forest with few dominants (expressed in highabundance of leaf specimens). On well-drained soils, lowland forest with large-leaved Lauraceae vel Fagaceae and rare elements (Fatsia) was present, while humid temperate broadleaf-deciduous and conifer forest flourished higher up. To infer palaeoclimate we used the Climate Leaf Analysis Multivariate Program (CLAMP) and compared the results with other Miocene localities of Turkey. Early Miocene floras had warm climates (mean annual temperature, MAT, and coldest month temperature, CMMT) with weak precipitation seasonality. MAT and CMMT were cooler during the early middle Miocene. Several fossil-taxa at Soma have biogeographic links with older/coeval localities in C Europe and/or the W Mediterranean region (cycads, Torreya, Dracaena, Smi-lax miohavanensis, Mahonia aff. pseudosimplex, Carya denticulata, Ilex miodipyrena, Pungiphyllum). Few taxa have clear links to C Asian floras (Comptonia longirostris). True E Mediterranean endemics are even rarer (Mahoniaspp., Quercus sosnowskyi).
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16. |
- Denk, Thomas, et al.
(author)
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Taxonomy and palaeoecology of two widespread western Eurasian Neogene sclerophyllous oak species: Quercus drymeja Unger and Q. mediterranea Unger
- 2017
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In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 241, s. 98-128
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Journal article (peer-reviewed)abstract
- Sclerophyllous oaks (genus Quercus) play important roles in Neogene ecosystems of south-western Eurasia. Modern analogues (‘nearest living relatives’) for these oaks have been sought among five of six infrageneric lineages of Quercus, distributed across the entire Northern Hemisphere. A revision of leaf fossils from lower Miocene to Pliocene deposits suggests that morphotypes of the Quercus drymeja complex are very similar to a number of extant Himalayan, East Asian, and Southeast Asian species of Quercus Group Ilex and may indicate subtropical, relatively humid conditions. Quercus mediterranea comprises leaf morphotypes that are encountered in modern Mediterranean species of Quercus Group Ilex, but also in Himalayan and East Asian members of this group indicating fully humid or summer-wet conditions. The fossil taxa Quercus drymeja and Q. mediterranea should be treated as morphotype complexes, which possibly comprised different biological species at different times. Quercus mediterranea, although readily recognizable as a distinct morphotype in early to late Miocene plant assemblages, may in fact represent small leaves of the same plants that constitute the Quercus drymeja complex. Based on the available evidence, the taxa [GG1] forming the Q. drymeja complex and Q. mediterranea thrived in fully humid or summer-wet climates. The onset of the modern vegetational context of Mediterranean sclerophyllous oaks is difficult to trace, but may have been during the latest Pliocene/early Pleistocene.
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17. |
- Eklöf, Martin, et al.
(author)
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OPENLAND3: a computer program to estimate plant abundance around pollen sampling sites from vegetation maps: a necessary step for calculation of pollen productivity estimates
- 2004
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 132:1-2, s. 67-77
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Journal article (peer-reviewed)abstract
- OPENLAND3 belongs to a suite of computer programs included in the POLLSCAPE simulation model. These programs make it possible to calculate estimates of pollen loadings in lake basins or bogs using vegetation data. OPENLAND3, written in Visual Basic 6, is designed to produce appropriate vegetation data files from vegetation maps stored in a Geographical Information System. It calculates percentage cover of plant taxa in concentric circles at increasing distances from a central point, using either real digitised maps or hypothetical maps (simulated landscape designs). Such data are necessary for simulation of pollen dispersal and deposition, and for calculation of pollen productivity estimates and relevant source area of pollen using specific mathematical models developed by palynologists, such as the Prentice-Sugita model. OPENLAND3 also produces output files needed to run RS-OPEN, another program included in POLLSCAPE, in order to obtain estimates of pollen loadings in lakes or bogs. The rationale of OPENLAND3, the algorithm used, and a modification of RS-OPEN (RS-OPEN2) are described. A test of the programme capability using a detailed vegetation map from southern Sweden shows that simulations using OPENLAND3 produce coherent results. Pollen loading for species characterized by high pollen productivity is higher than for species with low pollen productivity. Altering the wind speed has also a significant effect on pollen loading. As wind speed increases, the proportions of the light pollen decrease, while the heavy pollen types increase, which is what empirical data suggest, and what the model predicts in earlier studies. (C) 2004 Elsevier B.V. All rights reserved.
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18. |
- Elinor, Breman, et al.
(author)
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Phytolith-based environmental reconstruction from an altitudinal gradient in Mpumalanga, South Africa, 10,600 BP-present
- 2019
-
In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667 .- 1879-0615. ; 263, s. 104-116
-
Journal article (peer-reviewed)abstract
- Studying vegetation change across biome boundaries provides insight into vegetation resilience. In this study, shifts in grassland composition are reconstructed from sediments in three wetland sites across altitudinal gradient from 2128 to 897 m.a.s.l., representing a gradient from the grassland biome to the grassland/savanna boundary in the Mpumalanga region, north-eastern South Africa. Phytolith records from Verloren Valei (dated from 10,600 BP), Graskop (dated from 6500 BP) and Versailles (dated from 4500 BP) are used to reconstruct shifts in grassland composition and vegetation change. Phytolith morphotypes are used to construct environmental indices that are correlated with pollen main ecological groups, charcoal and delta 13C and C/N ratio. The results are compared to available regional paleoclimate data. Both Verloren Valei and Graskop have been dominated by grassland, but Versailles show a stronger influence of bushveld/savanna pollen. Phytolith data suggest that grassland composition was stable at Versailles and Graskop, but grassland at Verloren Valei has changed significantly over time. The early Holocene was dominated by a Pooideae/Chloridoideae C3 and C4 grassland, probably a remnant of the earlier Pleistocene cool-dry conditions. After 8500 BP grassland composition changed gradually to a Chloridoideae and Panicoidea dominated C4 grassland BP, and finally a moist Cyperaceae and Panicoidea dominated C3/C4 grassland after 4000 BP. This shift possibly occurs as a delayed response to the warmer and wetter conditions of the mid Holocene optimum at this high altitude site. The results suggest that the grassland/savanna boundary has remained stable over time, indicating considerable resilience of grasslands to climate change. This resilience may be related to the turnover of species within the grassland biome, as indicated by shifts between 8500 and 4000 BP at Verloren Valei.
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19. |
- Eriksson, Mats, et al.
(author)
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Silurian scolecodonts
- 2004
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 131:3-4, s. 269-300
-
Research review (peer-reviewed)abstract
- Scolecodonts, polychaete jaws, generally occur abundantly in Silurian shallow marine successions and are known from all continents except Antarctica. The assemblages are typically characterized by taxa with labidognath, placognath and prionognath type jaw apparatuses. They commonly include species of Kettnerites Zebera, 1935, Oenonites Hinde, 1879, Mochtyella Kielan-Jaworowska, 1961, Protarabellites Stauffer, 1933, Atraktoprion Kielan-Jaworowska, 1962, Pistoprion Kielan-Jaworowska, 1966, Vistulella Kielan-Jaworowska, 1961, Xanioprion Kielan-Jaworowska, 1962, Kalloprion Kielan-Jaworowska, 1962, and Leptoprion Kielan-Jaworowska, 1966. Less common genera, such as Hadoprion Eriksson and Bergman, 1998, Symmetroprion Kielan-Jaworowska, 1966 and Rhytiprion Kielan-Jaworowska, 1966, generally are recorded only from very large collections and/or suitable facies. Many of the common genera, as well as a few species, have been identified in several regions, particularly in Baltica and Laurentia, and evidently had a broad, intercontinental distribution. However, the scolecodont record from regions at higher paleolatitudes, i.e. Gondwana and peripheral paleoplates, is meager. In the famous latest Llandovery to latest Ludlow succession of Gotland, Sweden, scolecodonts are one of the most common microfossil groups, with abundances reaching thousands of specimens/kg rock. Based on an extensive collection, approximately one hundred jawed polychaete species belonging to at least 28 genera and a dozen families have been identified. Polychaetaspids, paulinitids and mochtyellids dominate. The exceptionally rare genus Synclinophora Eisenack, 1975, may belong to the family Oenonidae. If so, this is the only extant family represented in Silurian strata. The diversity patterns and temporal and stratigaphic distribution related to facies reveal that the assemblages house eurytopic as well as stenotopic taxa. Both long-ranging taxa, embracing the entire succession and beyond, and short-ranging taxa, occur. Like other metazoan groups, jawed polychaetes were affected by the documented Silurian extinction events. During the globally recognized late Ludlow Lau Event, approximately one third of the identified polychaete taxa went extinct, and some lineages show Lazarus gaps on Gotland. (C) 2004 Elsevier B.V. All rights reserved.
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20. |
- Feurdean, Angelica, et al.
(author)
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The influence of refugial population on Lateglacial and early Holocene vegetational changes in Romania
- 2007
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 145:3-4, s. 305-320
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Journal article (peer-reviewed)abstract
- Romania has for a long time been lacking good palaeoenvironmental records, particularly for the Late Quaternary. A chronological framework had been nearly absent and the vegetation development had been reconstructed entirely from pollen data. Data sets from this part of Europe are important for assessing the spatial variability of past vegetation and climatic changes and to reconstruct tree migration routes at the end of the last glacial period. New palaeobotanical evidence has enabled us to address this gap and to provide a more comprehensive picture of the Lateglacial and early Holocene continental environment. This paper reviews results from radiocarbon dated sequences in Romania with the aim to place them in a larger perspective with regard to glacial refugia and tree immigration, and to asses the vegetation response to climatic oscillation from the end of the Last Glacial Maximum (LGM) to the early Holocene. This study documents that some coniferous and broad-leaved trees were present prior to 14,700 cal. yr BP in Romania, and thus it appears that this region may have been a refugial area for some tree species. During the Lateglacial, the vegetation shows a distinct response to climatic oscillations at all elevations, although the response is stronger at mid attitude (800-1100 m. a.s.1) than at high altitudes. Moreover, smaller climatic oscillations are only recorded at sites situated at mid altitudes, probably because these areas were located close to the tree line ecotone. (c) 2007 Elsevier B.V. All rights reserved.
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21. |
- Friis, Else Marie, et al.
(author)
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Extinct seed plant diversity in the Early Cretaceous: An enigmatic new microsporangiate fossil with Decussosporites pollen in situ
- 2022
-
In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 304, s. 104716-104716
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Journal article (peer-reviewed)abstract
- A new microsporangiate cone, Renbernia zhoui, is described from the mesofossil flora extracted from exposures ofthe Potomac Group at Puddledock, Virginia, U.S.A., which are of Early Cretaceous (early-middle Albian) age. The cone consists of densely arranged dorsiventrally flattened laminar, flabelliform microsporangiophores that bear two elongate microsporangia on the presumed abaxial surface. The microsporangia are separated by sterile tissue that expands apically into a prominent hood-like sterile extension. The microsporangia have extrorse valvate dehiscence and both microsporangia and sterile apical expansion are covered by a short stiff hairs. In situ pollen resembles Decussosporites, elliptical with a long median colpus on the presumed distal surface flanked laterally by two equally long lateral colpi. A short transverse colpus on the presumed proximal surface links the two lateral colpi and divides the grain into two parts creating the appearance of two sacci. Renbernia zhoui is similar to Brenneria potomacensis described from the slightly older Drewry's Bluff and Dutch Gap mesofossil floras from the Potomac Group that also has Decussosporites-type pollen in situ. However, Renbernia microsporangiophores are more distinctly laminar and have sporangia that are more prominently elongated and with a hood-like apical extension of sterile tissue. The in situ pollen is also much smaller, the pollen wall is much more distinctly perforate-foveolate rather than more or less psilate, and in Renbernia the saccus-like structures are not inflated. The relationship of Brenneria and Renbernia, as well as the possible link between Decussosporites-type pollen and pollen of Eucommiidites (Erdtmanithecales) is discussed.
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22. |
- Friis, Else Marie, et al.
(author)
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Microsporangiophores from the Early Cretaceous (Berriasian) of Bornholm, Denmark, with comments on a pre-angiosperm xerophytic flora
- 2021
-
In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 293
-
Journal article (peer-reviewed)abstract
- A new taxon, Skyttegaardia galtieri, is described based on microsporangiophores with Monosulcites/Cycadopites pollen isolated from clays collected at the Skyttegård locality, island of Bornholm, Denmark, which are of earliest Cretaceous (Berriasian) age. Each microsporangiophore consists of a short, massive proximal fertile stalk-like portion with a truncate base, and a long sterile distal extension. A cavity on each side of the median line of the stalk-like portion, partially encloses a sporangium that dehisces by a longitudinal slit. The long distal extension tapers to a slender point and is curved toward the inferred adaxial side. The extension is irregularly angular in cross-section and the cuticle is thick with deep stomatal pits. The organization of the microsporangiophore, the in situ pollen and stomatal features suggest relationship with extant Cycadales. However, in all extant and fossil cycads there are usually many more sporangia per microsporangiophore, typically in groups of two to five, and they are borne on the surface of the proximal stalk-like portion rather than embedded in its tissues. These differences preclude secure inclusion of Skyttegaardia in Cycadales and open the possibility that these microsporangiophores were produced by a group of extinct plants, the other parts of which remain to be identified. The thick cuticle and sunken stomata of Skyttegaardia, together with the embedded sporangia, suggest adaptation to water stress, which is also consistent with the xeromorphic traits seen among the leaf fragments in the Skyttegaard flora and the arid conditions inferred from geological–geochemical proxies.
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23. |
- Gabarayeva, Nina, et al.
(author)
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Sporoderm development in Trevesia burckii (Araliaceae). I. Tetrad period: Further evidence for the participation of self-assembly processes
- 2009
-
In: Review of Palaeobotany and Palynology. - AMSTERDAM, NETHERLANDS : ELSEVIER SCIENCE BV. - 0034-6667 .- 1879-0615. ; 156:1-2, s. 211-232
-
Journal article (peer-reviewed)abstract
- The developmental events in the periplasmic space and cytoplasm of microspores, and in the tapetum of Trevesia burckii during the tetrad period have been traced in detail during microspore ontogeny from the sporogenous cell stage to the late tetrad stage and the initiation of the foot layer. The data obtained provide support to two of our previously proposed hypotheses: (1) the glycocalyx (scaffolding primexine matrix) is a colloidal system: (2) the involvement of processes of self-assembly of a number of colloidal micellar systems to the exine development. The main structures of the reticulate ectexine up to the establishment of the foot layer are columellae and tectum which evidently form on a base of spherical and cylindrical transitive micelle mesophases after sporopollenin accumulation. The importance of the callose envelope surrounding microspores; for exine development is discussed in the light of recent findings. Two possible pathways of pattern determination are possible. One suggests the role of the plasma membrane in pattern imprinting and the corresponding necessity of the transfer of 2-D information to 3-D. Our current supposition is that the other, self-assembly physical phenomena, cellular tensegrity, also participate in the process of the establishment of a wide-spread reticulate exine pattern which appears as the result of an interplay of the microspore cytoskeletal prestress and the resistance from the ECM (exocellular matrix = glycocalyx) adhesive sites. More and more information is appearing that provides evidence for the importance of mechanical forces and physico-chemical regularities in the living world.
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24. |
- Gabarayeva, Nina, et al.
(author)
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Sporoderm development in Trevesia burckii (Araliaceae) II. Post-tetrad period: Further evidence for the participation of self-assembly processes
- 2009
-
In: Review of Palaeobotany and Palynology. - AMSTERDAM, NETHERLANDS : ELSEVIER SCIENCE BV. - 0034-6667 .- 1879-0615. ; 156:1-2, s. 233-247
-
Journal article (peer-reviewed)abstract
- The developmental events in the periplasmic space, the cytoplasm of microspores and in the tapetum of Trevesia burckii have been traced in detail during microspore ontogeny from the late tetrad stage, through the post-tetrad period, to intine formation (following on from our study of the tetrad period also published herein). The data obtained give further support to our previously proposed hypothesis regarding self-assembly of a number of colloidal micellar systems during exine (and possibly intine) development. The main structures of the mature exine are columellae, granules and tripartite lamellae with central white lines which evidently form on a base of cylindrical, spherical and lamellar transitive micelle mesophases after sporopollenin accumulation. Further information provides evidence for the importance of physico-chemical regularities in pollen wall development.
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25. |
- Geier, Christian, et al.
(author)
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Paleovegetation and paleoclimate inferences of the early late Sarmatian palynoflora from the Gleisdorf Fm. at Gratkorn, Styria, Austria
- 2022
-
In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 307, s. 1-65
-
Journal article (peer-reviewed)abstract
- The Gleisdorf Formation (Fm.) deposits in the clay pit at Gratkorn, Styria, Austria, are dated to 12.2–12 Ma,and are of late Middle Miocene age (late Serravallian or Sarmatian). To reconstruct the paleovegetation and estimate the paleoclimate at this important vertebrate site, the palynoflora close to the boundary between the vertebrate-bearing layers of the Gratkorn Fm. and the overlying limnic clay deposits of the Gleisdorf Fm. was investigated. Using the single-grain method, 140 palynomorphs were identified. The palynoflora suggests that the paleovegetation was characterised by well-drained lowland and upland forests, riparian forest, and swamp forests. Depending on the dominating tree species, lowland and upland forests might have had closed or more open canopies. Open habitats included wet meadows and shrublands. In addition, conifers were present in theswampy lowlands and the forested uplands. The most prominent paleoclimatic signatures of the palynoflora indicate a fully humid warm temperate climate, with hot to warm summers and cool winters (Cfa-, Cfb-climate), and a seasonal climate with cool and drier winters and hot to warm and wetter summers (Cwa-, Cwb-climate). Our results align with existing studies bordering the Styrian Basin and support the presence of subtropical to warm-temperate vegetation around Gratkorn during the Sarmatian.
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26. |
- Grimm, Guido, et al.
(author)
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Fables and foibles: A critical analysis of the Palaeoflora database and the Coexistence Approach for palaeoclimate reconstruction
- 2016
-
In: Review of Palaeobotany and Palynology. - : Elsevier. - 0034-6667 .- 1879-0615. ; 233, s. 216-235
-
Journal article (peer-reviewed)abstract
- The ‘Coexistence Approach’ is amutual climate range (MCR) technique combinedwith the nearest-living relative (NLR) concept. It has been widely used for palaeoclimate reconstructions based on Eurasian plant fossil assemblages; most of them palynofloras (studied using light microscopy). The results have been surprisingly uniform, typically converging to subtropical, per-humid or monsoonal conditions. Studies based on the Coexistence Approach have had a marked impact in literature, generating over 10,000 citations thus far. However, recent studies have pointed out inherent theoretical and practical problems entangled in the application of this widely used method. But so far little is known how results generated by the Coexistence Approach are affected by subjective errors, data errors, and violations of the basic assumptions. The majority of Coexistence Approach studies make use of the Palaeoflora database (the combination of which will be abbreviated to CA + PF). Testing results produced by CA + PF studies has been hindered by the general unavailability of the contents in the underlying Palaeoflora database; two exceptions are the mean-annual temperature tolerances and lists of assigned associations between fossils and nearest-living relatives. Using a recently published study on the Eocene of China,which provides the first and only insight into the data structure of the Palaeoflora database,we compare the theory and practice of Coexistence Approach using the Palaeoflora database (CA+PF).We show that CA+PF is riddled by association and climate data error.We reveal flaws in the application of the Coexistence Approach,which is often in stark contrast to the theory of the method. We show that CA + PF is highly vulnerable against numerous sources of errors, mainly because it lacks safeguards that could identify unreliable data. We demonstrate that the CA+PF produces coherent, pseudo-precise results even for artificially generated, randomplant assemblages. AlternativeMCR-NLR methods can surpass the most imminent deficits of the Coexistence Approach, and may be used as a stop-gap until more accurate bioclimatic and distribution data on potential Eurasian NLRs, and theoretically and statistically robust methods will become available. Finally, general guidelines are provided for the future application of methods using the mutual climatic range with nearest living relatives approach when reconstructing climate from plant fossil assemblages.
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27. |
- Grindean, Roxana, et al.
(author)
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Relative pollen productivity estimates in the forest steppe landscape of southeastern Romania
- 2019
-
In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 264, s. 54-63
-
Journal article (peer-reviewed)abstract
- Estimates of relative pollen productivity (RPP) represent key input parameters for model-based quantitative reconstructions of past vegetation cover. In this study, we provide the first RPP estimates for 13 taxa from the forest steppe ecoregion in southeastern Romania (southeastern Europe). We used modern pollen assemblages from 26 points together with vegetation surveys and mapping, covering a 1.5 km radius around each sampling site. We have estimated the relevant source area of pollen (RSAP) and pollen productivity for 13 taxa relative to Poaceae using the ERV (Extended R-value model), sub-model 3, as this model shows the best goodness of fit. The estimated RSAP is about 100 m and falls within the range of RSAP estimates of moss pollsters and forest hollows from other RPP-related studies. Results show that Rubiaceae (7.97), Apiaceae (5.91), Artemisia (5.89) and Fraxinus (2.99) are high pollen producers compared to Poaceae, while Plantago lanceolata (0.58), Fabaceae (0.40), Acer (0.30), Rosaceae (0.29), Carpinus orientalis (0.24), Cerealia (0.22) and Asteraceae (0.16) are low pollen producers with lower RPPs than Poaceae. Quercus (1.10) has a pollen productivity close to that of Poaceae. The RPPs for Carpinus orientalis and Fabaceae are published here the first time for Europe. The high pollen producing plants include both entomophilous and anemophilous species, while the low pollen producers are mostly entomophilous species. Our results form an essential contribution to improving the accuracy of quantitative reconstruction of forest steppe ecoregion in Europe and generally in regions with a similar climate and vegetation setting.
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28. |
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29. |
- Harland, R., et al.
(author)
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Dinoflagellate cysts from the ‘Anthropocene’ of Gullmar Fjord, west coast of Sweden and their potential for monitoring climate change
- 2019
-
In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 261, s. 31-40
-
Journal article (peer-reviewed)abstract
- A small set of samples from Gullmar Fjord, on the west coast of Sweden, together with published data, has allowed the investigation of the ‘Anthropocene’ within the fjord. The dinoflagellate cyst record and its statistical analysis fails to show any marked changes within the assemblages either across the proposed boundary or indeed within the youngest sediments at the top of the sequence. However there are some small scale differences in the youngest assemblages that are of interest. In particular these include quantitative shifts in the numbers of some of the species especially Pentapharsodinium dalei, which may be indicative of somewhat cooler environments linked to the winter North Atlantic Oscillation (NAO) and extra availability of nutrients from Ekman pumping. These small scale shifts in the assemblages point to clear dynamism within the phytoplankton populations reacting to both anthropogenic and natural environmental change; evidence of the complexity of the system. The proven utility of dinoflagellate cysts in charting climate change throughout both the Pleistocene and Holocene within Gullmar Fjord, and elsewhere along the west coast of Sweden is in marked contrast to the little change at the ‘Anthropocene’ boundary. Nonetheless the geographical position of the fjords along the Skagerrak are ideal to monitor environmental change within the North Sea basin and perhaps further afield in the eastern North Atlantic Ocean; especially since further climate change threatens regime change within the marine environment affecting tourism, industry and mariculture along the coast. © 2018 Elsevier B.V.
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30. |
- Hazra, Taposhi, et al.
(author)
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New discovery of rare insect damage in the Pliocene of India reinforces the biogeographic history of Eurasian ecosystems
- 2022
-
In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 298, s. 104589-104589
-
Journal article (peer-reviewed)abstract
- Plant–insect interactions in the fossil record are, as yet, sparsely known and understudied. Here, we document evidence of a new type of insect skeletonization on Abroma augustum (L.) L. f. (Malvaceae) leaf remains fromthe latest Neogene (Pliocene) sediments of Chotanagpur plateau, Jharkhand, eastern India. This unique skeletonization feeding trace attributable to herbivorous insects occurs all over the surfaces of our recovered Pliocene leaf remains. In the skeletonized area, the interveinal tissues are completely removed leaving behind only the tough leaf veins. This type of insect feeding behaviour is documented for the first time on Indian Cenozoic leaf remains. Based on published data, as well as our survey of modern forests adjacent to the fossil locality, we suggest that probable damage inducers of this skeletonization on Abroma Jacq. fossil leaves might be Chrysomelid (Coleopteran) beetles. This finding also reveals that specific insect feeding damage, such as the one presented here, can reveal similarity of environments despite the difference of plant species observed. Such results strengthen the importance of using plant–insect interactions on leaves as a complementary proxy to others revealing paleoenvironmental conditions.
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31. |
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32. |
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33. |
- Hellman, Sofie, et al.
(author)
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Estimating the Relevant Source Area of Pollen in the past cultural landscapes of southern Sweden : A forward modelling approach
- 2009
-
In: Review of Palaeobotany and Palynology. - : Elsevier. - 0034-6667 .- 1879-0615. ; 153:3-4, s. 259-271
-
Journal article (peer-reviewed)abstract
- In this paper, we estimate the Relevant Source Area of Pollen (RSAP) in past hypothetical landscapes of the Middle and Late Holocene in southern Sweden, in order to explore the possible effects of past changes in vegetation composition, openness and structure in terms of patch size and spatial distribution. The RSAP of small basins (bogs or lakes) in the past has to be estimated if quantitative reconstruction of past vegetation at the local spatial scale is to be achieved using Sugita's Landscape Reconstruction Algorithm (LRA). In this study we apply a forward modelling approach to estimate past RSAP using the computer simulation model HUMPOL The landscape designs are based on past landscape maps produced using a combination of palaeobotanical, archaeological and historical data, and the area's geology and soil characteristics. Four time windows characterised by different landscape/land-use were selected, i.e. Early Neolithic, Late Bronze Age, Viking Age, and Middle Ages. We found that RSAP estimates for hypothetical past landscapes in Skane differ by ca. 600 m to 1200 m between the selected time periods, whatever the size of the basin (lake or bog, 25250 m radius). The most probable explanation for the differences in RSAP between time slices is variable patch size and spatial distribution of patches in the landscape. The RSAPs vary between ca. 1200 and 2300 m for small basins (25 m and 70 m radius), and between ca. 2000 and 3000 m for larger basins (250 m radius). These values are within the range of earlier estimates of modern and past RSAPs for southern Scandinavia obtained using simulated or empirical data. These results suggest that, given the type of setting of that region in terms of taxa composition and traditional land-use, the RSAP for small-size lakes (25-250 m radius) will generally be in the range ca. 1200-3000 m. The forward modelling approach is found to be useful to assess the possible effects on RSAP of changes in vegetation/landscape characteristics between different periods of the past. Moreover, comparison of RSAP estimates obtained using both the forward and backward modelling approaches will be important to identify the most credible RSAP estimates for the past.
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34. |
- Hellman, Sofie, et al.
(author)
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Relevant Source Area of Pollen in patchy cultural landscapes and signals of anthropogenic landscape disturbance in the pollen record : A simulation approach
- 2009
-
In: Review of Palaeobotany and Palynology. - : Elsevier. - 0034-6667 .- 1879-0615. ; 153:3-4, s. 245-258
-
Journal article (peer-reviewed)abstract
- Using the HUMPOL simulation computer model we explored the effects of various factors characteristic of mosaic cultural landscapes on the Relevant Source Area of Pollen (RSAP sensu Sugita) of small lakes (50 m radius), and the representation of NAP and human-impact pollen indicators in small takes. The following aspects were tested: 1) effect of variations in the spatial distribution of taxa/patches and species diversity on RSAP, 2) effect of changes in the proportion of landscape openness and size of openings on the RSAP and the pollen signal, and 3) the value of low-abundance anthropogenic indicator species to detect openness in the landscape. Moreover, we examined a methodological aspect of the MOSAIC computer program, i.e. the variability in RSAP due to inherent variations between replicates of random landscape simulation scripts using the program MOSAIC. We found differences in the RSAP estimates between runs using replicates of the same landscape created in the program MOSAIC. Such differences need to be taken into account when interpreting results involving the use of MOSAIC replicates. The simulations suggest that, if the model assumptions are valid, the RSAP is sensitive to vegetation structure in terms of patch size, and taxa/patch diversity and spatial distribution, whatever the properties of the taxa modelled. The longer the distance from each sampling site to get a sufficient cover of all taxa within the landscape, the larger the RSAP. If the spatial distribution of patches is very uneven and/or some taxa/patches are characterised by low frequencies in the randomized landscape, this distance will become longer. Further analysis of the results and new modelling experiments are necessary to provide better means for testing the presented hypothesis on the effect of spatial vegetation/landscape evenness on RSAP. The simulations indicate that, in hypothetical mosaic tree/herb landscapes including common NW European taxa of traditional cultural landscapes, RSAP estimates are relatively robust, i.e. will seldom be smaller than 1000 m and larger than 2500 m in radius in the case of 50 m radius lakes. NAP percentage is not a reliable "measure" of landscape openness. A NAP percentage value may represent a large range of openness percentage cover depending on the size and spatial distribution of the openness patches. Common pollen indicators of human impact and landscape openness will be represented in a pollen assemblage from small lakes when the landscape is relatively open (>= 30%) and a minimum of 300-1000 grains is counted. Findings of pollen indicators of human impact may not be as reliable indicators of land use within the RSAP as has sometimes been assumed, especially when human activity is small scale. Moreover, it is important to realize that a small number of grains may indicate relatively large overall openness cover in the landscape, especially if the open areas consist of few large clearings rather than many small clearings.
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35. |
- Heřmanová, Zuzana, et al.
(author)
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Reinterpretation of fossil reproductive structures Zlivifructus microtriasseris (Normapolles complex, Fagales) from the Czech and Polish Late Cretaceous
- 2019
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667.
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Journal article (peer-reviewed)abstract
- Flowers and fruits of Zlivifructus microtriasseris, originally described as Caryanthus microtriasseris from the late Turonian to Santonian of the South Bohemian Basins and the late Coniacian to early Santonian of the North Sudetic Basin, are reinterpreted here. Zlivifructus microtriasseris is represented by small, flat fruits, round in outline with persistent perianths, which are fused basally, forming the hypanthium. The hypanthium extends for more than two-thirds of the fruit. Tepals leave scars indicating their insertion. Lateral attachment scars of tepals and medial attachment scars are immediately adjacent to each other, with indistinct boundaries forming a ring. The androecium consists of four stamens. The fruit shows the unilocular nature of the nut with a single seed. Lateral faces of the fruit show two parallel ribs or ridges, running from the base of the fruit to the margin of the hypanthium. The surface of the fruit bears irregularly shaped cells. Zlivifructus microtriasseris differs from species assigned to genus Caryanthus Friis 1983 in the presence of four stamen scars, and in having two lateral ribs in the face of the fruit. Zlivifructus microtriasseris differs from the type species Zlivifructus vachae in size of the fruit; shape of the fruit; perianth and attachment scars of tepals. A probabilistic classification method to differentiate between the two fruit species based on their size is proposed.
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36. |
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37. |
- Hofmann, Christa-Charlotte, et al.
(author)
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Scanning electron microscopy investigation of monads and tetrads of basal core eudicots from the Upper Cretaceous Vilui Basin, Siberia: Evidence for reticulate evolution
- 2011
-
In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 167:3-4, s. 196-211
-
Journal article (peer-reviewed)abstract
- Non-marine Late Cretaceous sediments from the Vilui Basin, Siberia, yield a diverse palynoflora of over 180 taxa, a third of which had a circum-polar distribution. The Vilui palynoflora belongs generally to the northerly Aquilapollenites Province admixed with minute Normapolles types, and comprises about 36-70% angiosperm pollen forms, indicating a late Campanian/early Maastrichtian age. Using a combination of light and scanning electron microscopy we examined well-known stratigraphic taxa such as Aquilapollenites mtchedlishvilii Srivastava, Aquilapollenites decorus Srivastava Azonia recta Bolkhovitina and Tricerapollis minutus Chlonova. Further we present pollen belonging to early eudicots such as Saxifragales (Cercidiphyllaceae, Altingiaceae and Hamamelidaceae), basal eudicots (? Buxaceae) and basal core eudicots (?Gunnerales) that are preserved as colpate or porate forms, some of which are preserved as obligate tetrads, such as the morphogenera Virgo Ward, Artiopollis (Agasie) Singh, and Senectoteradites Dettmann while others are preserved as single grains or in pollen aggregations, such as Periporopollenites (Potonie) Pflug &Thomson, Retitricolpites (van der Hammen) Pierce and unnamed tricolpate types. The following new species are introduced: Virgo nicholsii, Artiopollis tyungensis, Artiopollis bellus, Periporopollenites sakhaensis, and Senectotetradites viluiensis. Our approach revealed features suggesting that individual grain types exhibit affiliations to more than one extant family. This mirrors trans-familial characters also observed in Late Cretaceous leaf fossils and is typical of reticulate evolution. (C) 2011 Published by Elsevier B.V.
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38. |
- Jansson, Ida-Maria, et al.
(author)
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An Early Jurassic flora from the Clarence-Moreton Basin, Australia
- 2008
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 150:1-4, s. 5-21
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Journal article (peer-reviewed)abstract
- A low-diversity Early Jurassic flora preserved in floodbasin siltstones of the Marburg Subgroup at Inverleigh Quarry in the Clarence-Moreton Basin, eastern Australia, is dominated by Allocladus helgei Jansson sp. nov., a conifer with denticulate leaves tentatively attributed to Araucariaceae. The assemblage also includes Rintoulia variabilis and Caytoniales, (Caytonia cucullata McLoughlin sp. nov. and cf. Sagenopteris nilssoniana), reinforcing the wide distribution of this order in Early to Middle Jurassic floras of Gondwana. Ferns (Cladophlebis and Sphenopteris species) and isoetalean lycophytes (Isoetites sp.) constitute the herbaceous elements of the flora. The palynoflora is dominated by cheirolepidiacean (Classopollis) pollen and is attributable to the upper part of the Corollina (=Classopollis) torosa Zone of late Pliensbachian-early Toarcian age (180-185 Ma). The Inverleigh flora represents one of the few Australian assemblages dated between the major phases of floristic turnover at the end of the Triassic and the Toarcian. Sedimentological characteristics, cuticular features of the conifer leaves and the abundance of free-sporing plants indicate a relatively humid palaeoclimate for the Clarence-Moreton Basin Early Jurassic.
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39. |
- Larsson, Linda, et al.
(author)
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Vegetation and climate in the latest Oligocene-earliest Miocene in Jylland, Denmark
- 2010
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 159:3-4, s. 166-176
-
Journal article (peer-reviewed)abstract
- Two exposures in Jylland, Denmark, encompassing beds of latest Oligocene to earliest Miocene age (latest Chattian-early Aquitanian) yielded well-preserved palynofloras. The assemblages indicate that Jylland was covered by extensive Taxodiaceae swamp forests in the mid-Cenozoic. Besides a Taxodiaceae-Cupressaceae association, which was overwhelmingly dominant, other common plants in this habitat were Alnus, Nyssa, Betula, Salix, Cyrilla and Myrica. Most of the trees and shrubs are well adapted to swamps and thrive under more or less flooded conditions in modern bald cypress swamps of the southeastern North America. Vegetation composition indicates that a warm-temperate climate prevailed in Denmark during the Oligocene-Miocene transition. According to calculations using the Coexistence Approach, the mean annual temperature during this time span ranged from 15.6 to 16.6 degrees C. An increase to 16.5-21.1 degrees C is inferred from the palynoflora in the upper part of the section. The earlier, cooler period possibly reflects global cooling associated with the Mi-1 glaciation event at the Oligocene-Miocene boundary. No data from the very coldest part of the Mi-I event has been recorded, as this is represented by a gravel layer (representing a hiatus) in the lowermost part of the studied succession. The length of the missing time is not known precisely, but is probably in the order of some hundred thousand years. Correlation with the well-established chronostratigraphic and sequence stratigraphic framework for the studied succession reveals that the most distinctive change in palynoflora probably reflects a shift in depositional facies (due to an increase in sea level) rather than direct climatic change. The sea-level rise is herein interpreted to be eustatic and related to melting of Antarctic ice caps at the end of the Mi-1 glaciation event. (C) 2010 Elsevier B.V. All rights reserved.
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40. |
- Lazarova, Maria, et al.
(author)
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A 5000-year pollen and plant macrofossil record from the Osogovo Mountain, Southwestern Bulgaria : Vegetation history and human impact
- 2015
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667 .- 1879-0615. ; 223, s. 1-9
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Journal article (peer-reviewed)abstract
- Pollen and plant macrofossil analyses were performed on a sequence 105 cm deep obtained from a peat bog (1750 m) that is located above the present timber-line in the Osogovo Mountain, Southwestern Bulgaria. The palaeovegetation reconstruction, supported by a radiocarbon chronology, revealed the vegetation dynamics and human impact during the last 5000 years. The peat bog formed when a coniferous belt of Abies alba and Pinus (Pinus sylvestris, Pinus nigra) covered the high mountain slopes. Charcoal fragments indicate the presence of a broad-leaved tree community composed of Quercus, Corylus, Carpinus, Tilia, Acer and Ulmus at lower altitudes. Stands of Fagus sylvatica in places with higher air and soil humidity, like river valleys and deep ravines, became established. The pollen assemblages after c. 3200 cal. BP record an important change in the forest composition that led to the replacement of the conifers, mostly A. alba, by the invading communities of F. sylvatica. The reasons for this replacement included factors related to both climate change and anthropogenic disturbance. During the last centuries a large-scale degradation of the woodlands in the mountain has occurred. On a regional scale the palaeoecological evidence is compared with information from palynological, archaeological and historical sources in Southwestern Bulgaria.
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41. |
- Li, Yiyin, et al.
(author)
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Pollen production estimates (PPEs) and fall speeds for major tree taxa and relevant source areas of pollen (RSAP) in Changbai Mountain, northeastern China
- 2015
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In: Review of Palaeobotany and Palynology. - 0034-6667. ; 216, s. 92-100
-
Journal article (peer-reviewed)abstract
- For model-based quantitative reconstructions of past vegetation cover on the scale of landscapes, pollen productivity estimates (PPEs) are key input parameters. In this study, we employed a random sampling strategy to collect moss polsters at 20 sites in Changbai Mountain, northeastern China. A detailed vegetation survey within 1000-m radius around each sampling point was carried out and digitized vegetation maps were used for, vegetation data compilation. A forest map at the scale of 1:25,000 was used to extract information about vegetation for the area between 1000 and 5000 m from each sampling point. Using the ERV (Extended R-Value) model, pollen productivity was estimated for Larix, Pinus, Juglans, Ulmus, Tilia, Betula and Fraxinus relative to Quercus. Estimates of pollen fall speeds for the eight taxa as well as the relevant source area of pollen (RSAP) were also obtained. Three different ERV sub-models were tested against the data. The sub-model 3 produced the best goodness of fit and the PPE values calculated with this sub-model show that BMA (5.04), Pinus (3.11), Juglans (1.94) and Ulmus (1.40) are high pollen producers with higher PPEs than Quercus while Fraxinus (0.76), Larix (0.30), Tilia (0.16) are low pollen producers compared to Quercus. The high pollen producers are all anemophilous species, while low pollen producing plants include both entomophilous, such as Fraxinus, Tilia and anemophilous species such as Larix. The estimated RSAP for the eight tree pollen taxa is about 2000-2500 m. (C) 2015 Elsevier B.V. All rights reserved.
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42. |
- Lindström, Sofie
(author)
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Early-Late Permian palynostratigraphy and palaeobiogeography of Vestfjella, Dronning Maud Land, Antarctica
- 1995
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In: Review of Palaeobotany and Palynology. - 0034-6667. ; 86:1-2, s. 157-173
-
Journal article (peer-reviewed)abstract
- The preliminary results of a palynological investigation of 62 samples from the southern section of a sedimentary sequence exposed at Fossilryggen in the Vestfjella mountain range in Dronning Maud Land, Antarctica are reported. The sequence, which is cut by dolerite dykes, is considered to have been deposited in a near-shore marine environment. Palynomorphs recovered show high degrees of thermal alteration and various states of preservation; 55 palynomorph taxa have been identified, including the stratigraphically important Didecitriletes ericianus, Microbaculispora villosa, M. trisina, Horriditriletes filiformis, Praecolpatites sinuosus, Weylandites lucifer, Protohaploxypinus rugatus, Striatopodocarpidites cancellatus and S. fusus. Also present are acritarchs, such as Peltacystia venosa, P. monile and Circulisporites sp., and prasinophycean algae, such as Cymatiosphaera gondwanensis. Palaeobiogeographically the palynoflora is typical for southern Gondwanaland and it is correlated primarily with assemblages of similar composition in Antarctica, South Africa and Australia. Comparisons are also made with assemblages from the northern margins of Gondwanaland and Eurameria, with which palynostratigraphical correlations are more difficult. No typical Euramerian taxa have been found in the palynoflora from Fossilryggen, which is assessed as no older than Australian Lower Stage 5b and 5c assemblages and is considered to be of early Late Permian (Ufimian) age.
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43. |
- Lindström, Sofie
(author)
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Early Permian palynostratigraphy of the northern Heimefrontfjella mountain range, Dronning Maud Land, Antarctica
- 1995
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In: Review of Palaeobotany and Palynology. - 0034-6667. ; 89:3-4, s. 359-415
-
Journal article (peer-reviewed)abstract
- Permian rocks from five localities in the northern Heimefrontfjella have been investigated palynologically and identifiable palynomorphs are present in samples from three of them, namely A and C in Milorgfjella and Lidkvarvet in Sivorgfjella. Eighty palynomorph taxa are recognized and two new combinations are proposed, Converrucosisporites gradegranulatus (Anderson) Lindstrom, comb, nov, and Cannanoropollis bilateralis (Tiwari) Lindstrom, comb. nov. Seventeen taxa are placed in open nomenclature. The assemblages from Locality A and Lidkvarvet are moderately well-preserved, taxonomically diverse, and are indicative of palynofloras deposited in periglacial, cold-climate, freshwater environments. They contain many typical Early Permian Gondwana taxa such as: lycopod spores Jayantisporites pseudozonatus and J. conatus; pterophyte spores Leiotriletes spp., Microbaculispora tentula, Horriditriletes spp., Verrucosisporites andersonii, Cyclogranisporites spp. and Punctatisporites gretensis; and gymnospermous pollen-grains Plicatipollenites spp., Cannanoropollis spp., Scheuringipollenites spp., Pteruchipollenites gracilis, Protohaploxypinus spp. and Cycadopites cymbatus. The presence of these: along with the pterophyte spore Pseudoreticulatisport a confluens enables correlation with the P. confluens Zone or Late Stage 2 of Australia and equivalents in other Gondwana continents, indicating an Asselian-Tastubian age for these two localities. Assemblages assigned to the Pseudoreticulatispora confluens Zone have previously not been encountered within Antarctica. The assemblage from Locality C is poorly preserved with low taxonomic diversity, and contains only one species which is not present in the assemblages from the other two localities, namely Microbaculispora trisina. This suggests correlation with the M. trisina zone or Stage 3b palynofloras of Australia and equivalents elsewhere in Gondwana, and an age no older than Artinskian.
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44. |
- Lindström, Sofie, et al.
(author)
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Synchronous palynofloristic extinction and recovery after the end-Permian event in the Prince Charles Mountains, Antarctica: Implications for palynofloristic turnover across Gondwana
- 2007
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667. ; 145:1-2, s. 89-122
-
Research review (peer-reviewed)abstract
- In the Prince Charles Mountains (PCMs) the conformable Permian-Triassic (P-T) succession is characterised by an abrupt transition from coal-bearing to coal-lacking strata, which coincides with the demise of the Permian Glossopteris-dominated flora. About 32% of the typical Permian spores and pollen are registered for the last time in the uppermost coal. Throughout the earliest Triassic an additional 34% of the lingering Permian taxa disappear, while pioneering typical Triassic taxa appear. This interval of contemporaneous stepwise extinction and recovery resulted in an actual increase in spore-pollen taxa diversity during the earliest Triassic. The estimated average sedimentation rate indicates that the 24 m sampling gap that separates the last Permian assemblage from the first Triassic one represents ca 96000 years, and that the continued stepwise extinction and recovery lasted for ca 325 000 years. In the aftermath of the end-Permian crisis only 27% of the typical Permian spores and pollen, that were present from the lower McKinnon Member in the Prince Charles Mountains survived to the late Induan, but by then the biodiversity had only decreased by less than 10%. Comparisons of Gondwanan palynological and lithological data indicate that intense global warming had already begun in the Permian, and that high latitude Gondwana areas such as the PCMs, were affected later than areas to the north and west. They also suggest that the end-Permian crisis affected the various Gondwana regions in different ways, but that the end result appears to have been a more equable, sub-humid to semi-arid, and less seasonal climate across southern Gondwana.
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45. |
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46. |
- Mays, Chris, 1983-, et al.
(author)
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The botanical provenance and taphonomy of Late Cretaceous Chatham amber, Chatham Islands, New Zealand
- 2019
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In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 260, s. 16-26
-
Journal article (peer-reviewed)abstract
- Fossil resin (amber) has been recently reported as common, but small, sedimentary components throughout thelower Upper Cretaceous (Cenomanian; 99–94 Ma) strata of the Tupuangi Formation, Chatham Islands, easternZealandia. From these deposits, resin has also been identified and obtained from well-preserved, coalified specimensof the conifer fossil Protodammara reimatamorioriMays and Cantrill, 2018. Here, we employed attenuatedtotal reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) to both dispersed and in situ amber specimens.These resulted in very similar chemical signatures, indicating that these fossils are likely from the same orclosely-related botanical sources. The FTIR data are typical of a conifer source within the ‘cupressaceous resins’category of Tappert et al. (2011). Carbon-13 nuclear magnetic resonance spectroscopy (13C NMR) facilitatedthe probable identification of these ambers as ‘Class Ib' (sensu Anderson et al. 1992). Based on these spectraldata sets, the likely botanical sources of the amber were either Araucariaceae or Cupressaceae; both of these coniferfamilies were common and widespread in the Southern Hemisphere during the Cretaceous. However, themorphology and anatomy of P. reimatamoriori support an affinity to the latter family, thus indicating that the Cretaceousamber of the Chatham Islands was generally produced by members of the Cupressaceae. Comparing theFTIR data to the published spectra of modern resins, we also identify a band ratio which may aid in distinguishingbetween the FTIR spectra of Araucariaceae and Cupressaceae, and outline the limitations to this approach. A highconcentration of ester bonds in Chatham amber specimens, which exceeds typical Cupressaceae resins, is probablycaused by taphonomic alteration via thermal maturation. The source of thermal alteration was likely preburialwildfires,conditions forwhich P. reimatamoriori was adapted to as part of its life cycle. A comparison of ambersof the Chatham Islands with modern resins and amber from various localities in Australasia reveals that,taphonomic influences aside, Chatham amber has a unique signature, suggesting that members of the basalCupressaceae (e.g., Protodammara) were not major contributors to other documented Australasian amber deposits.The closest analogy to Chatham amber deposits appears to be the Upper Cretaceous Raritan Formation,USA, which is characterised by its rich amber, charcoal and Cupressaceae fossil assemblages. This study furthersupports the hypotheses that the early Late Cretaceous south polar forests were dominated by Cupressaceae,and regularly disturbed by wildfires.
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47. |
- Mazier, F., et al.
(author)
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Testing the effect of site selection and parameter setting on REVEALS-model estimates of plant abundance using the Czech Quaternary Palynological Database
- 2012
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In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667 .- 1879-0615. ; 187, s. 38-49
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Journal article (peer-reviewed)abstract
- REVEALS-based quantitative reconstruction of Holocene vegetation cover (expressed in plant functional types. PFTs) is used in the LANDCLIM project to assess the effect of human-induced land-cover change on past climate in NW Europe. Using the Czech Quaternary Pollen Database, this case study evaluates the extent to which selection of data and input parameters for the REVEALS model applications would affect reconstruction outcomes. The REVEALS estimates of PFTs (grid-cell based REVEALS PET estimates, GB REVEALS PFT-s) are calculated for five time windows of the Holocene using fossil pollen records available in each 1 degrees x1 degrees grid cell of the Czech Republic. The input data and parameters selected for testing are: basin type and size, number of C-14 dates used to establish the chronology of the pollen records, number of taxa, and pollen productivity estimates (PPE). We used the Spearman correlation coefficient to test the hypothesis that there is no association between GB REVEALS PET-s using different data and parameter inputs. The results show that differences in the basin size and type, number of dates, number and type of taxa (entomophilous included or not), and PPE dataset do not affect the rank orders of the GB REVEALS PET-s significantly, except for the cases when entomophilous taxa are included. It implies that, given careful selection of data and parameter and interpretation of results, REVEALS applications can use pollen records from lakes and bogs of different sizes together for reconstruction of past land cover at the regional to sub-continental spatial scales for purposes such as the study of past land cover-climate interactions. Our study also provides useful criteria to set up protocols for data compilation REVEALS applications of this kind. (C) 2012 Elsevier B.V. All rights reserved.
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48. |
- McLoughlin, Stephen, 1964-, et al.
(author)
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Paurodendron stellatum: a new Permian permineralized herbaceous lycopsid from the Prince Charles Mountains, Antarctica
- 2015
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In: Review of Palaeobotany and Palynology. - : Elsevier. - 0034-6667 .- 1879-0615. ; 220, s. 1-15
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Journal article (peer-reviewed)abstract
- Diminutive, silica-permineralized lycopsid axes, from a Guadalupian (Middle Permian) silicified peat in the Bainmedart Coal Measures of East Antarctica are described and assigned to Paurodendron stellatum sp. nov. Axes consist only of primary-growth tissues with a vascular system characterized by an exarch actinostele with 6–20 protoxylem points. Stems have a relatively narrow cortex of thin-walled cells that are commonly degraded, but the root cortex typically contains more robust, thick-walled cells. The stems bear helically inserted, elliptical–rhombic, ligulate microphylls. Roots possess an eccentrically positioned monarch vascular strand. Paurodendron stellatum is one of a very small number of anatomically preserved lycopsid axes described from the Gondwanan Permian and represents the first post-Carboniferous record of this genus. Based on dispersed vegetative remains, megaspores and microspores, herbaceous lycopsids, such as P. stellatum, appear to have been important understorey components of both low- and high-latitude mire forests of the late Palaeozoic.
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49. |
- McLoughlin, Stephen, 1964-, et al.
(author)
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Synchrotron X-ray imaging reveals the three-dimensional architecture of beetle borings (Dekosichnus meniscatus) in Middle–Late Jurassic araucarian conifer wood from Argentina
- 2022
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In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; , s. 104568-104568
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Journal article (peer-reviewed)abstract
- Longitudinally aligned borings attributed to the ichnotaxon Dekosichnus meniscatus in the inner secondary wood of a silicified Middle–Late Jurassic conifer from Argentina contain finely granular frass particles arranged in meniscoid laminae. Synchrotron X-ray computed tomographic reconstruction of the borings reveals new characters of this ichnotaxon, such as opposing orientations of menisci in some adjacent borings, regular spacing of minor and major meniscoid laminae, a scarcity of tunnel branching, and rare occurrences of cylindrical–spherical terminal chambers on excavations. Architectural and distributional features of the galleries suggest excavation by cerambycid beetle larvae, thus representing one of the earliest potential fossil records of this group. The borings are confined to the inner wood of a young tree that experienced a moderately seasonal climate in a volcanically influenced landscape. By detecting subtle heterogeneities in composition, this study demonstrates that high-energy synchrotron X-ray tomography can characterize anatomical features and complex ecological interactions within even densely permineralized (silicified) plant fossils.
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50. |
- McLoughlin, Stephen, 1964-, et al.
(author)
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The reproductive biology of glossopterid gymnosperms—A review
- 2021
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In: Review of Palaeobotany and Palynology. - Amsterdam : Elsevier. - 0034-6667 .- 1879-0615. ; 295, s. 104527-104527
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Journal article (peer-reviewed)abstract
- We review recent advances on glossopterid reproductive biology and their implications for seed plant phylogeny and the ecology of this widespread Permian Gondwanan group. Microsporangiate organs are interpreted to have been arranged in loose compound cones—an organization that evokes comparisons with Ginkgoales, Cordaitales and early conifers. The pollen was typically taeniate, bisaccate, and primarily adapted to wind dispersal. The diverse ovuliferous organs generally incorporated some form of marginal flange or wing. In most cases, the wing was probably protective, wrapping around the ovules during early development. However, we postulate that some conspicuous flanges were potentially analogous to angiosperm petals, functioning as corolla-like guides to attract insect pollinators. The arrangement of seed-bearing polysperms adnate to the subtending leaf to form a fertiliger in glossopterids represented another means of protecting the ovules. In some cases, highlighting the polysperm against the attached leaf might have increased the showiness of the ovule-bearing part for pollinators. In other cases, detachment of the fertiliger may have aided anemochory by retarding seed fall through rotation analogous to dispersal in extant Tilia. The microgametophyte in glossopterids is characterized by a short, weakly branched, haustorial tube, and the release of motile sperm cells. At least some seeds of glossopterids express polyembryony. Mature seeds possessed various micropylar modifications for the entrapment of pollen, and winged or bulbous expansions of the outer integument to aid anemochory or possibly hydrochory. Vegetative regeneration as a response to damage occurred via epicormic buds and possibly by the development of lignotubers.
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