TY - JOUR A1 - Gosling, William D. A1 - Julier, Adele C. M. A1 - Adu-Bredu, Stephen A1 - Djagbletey, Gloria D. A1 - Fraser, Wesley T. A1 - Jardine, Phillip E. A1 - Lomax, Barry H. A1 - Malhi, Yadvinder A1 - Manu, Emmanuel A. A1 - Mayle, Francis E. A1 - Moore, Sam T1 - Pollen-vegetation richness and diversity relationships in the tropics JF - Vegetation History and Archaeobotany N2 - Tracking changes in biodiversity through time requires an understanding of the relationship between modern diversity and how this diversity is preserved in the fossil record. Fossil pollen is one way in which past vegetation diversity can be reconstructed. However, there is limited understanding of modern pollen-vegetation diversity relationships from biodiverse tropical ecosystems. Here, pollen (palynological) richness and diversity (Hill N (1)) are compared with vegetation richness and diversity from forest and savannah ecosystems in the New World and Old World tropics (Neotropics and Palaeotropics). Modern pollen data were obtained from artificial pollen traps deployed in 1-ha vegetation study plots from which vegetation inventories had been completed in Bolivia and Ghana. Pollen counts were obtained from 15 to 22 traps per plot, and aggregated pollen sums for each plot were > 2,500. The palynological richness/diversity values from the Neotropics were moist evergreen forest = 86/6.8, semi-deciduous dry forest = 111/21.9, wooded savannah = 138/31.5, and from the Palaeotropics wet evergreen forest = 144/28.3, semi-deciduous moist forest = 104/4.4, forest-savannah transition = 121/14.1; the corresponding vegetation richness/diversity was 100/36.7, 80/38.7 and 71/39.4 (Neotropics), and 101/54.8, 87/45.5 and 71/34.5 (Palaeotropics). No consistent relationship was found between palynological richness/diversity, and plot vegetation richness/diversity, due to the differential influence of other factors such as landscape diversity, pollination strategy, and pollen source area. Palynological richness exceeded vegetation richness, while pollen diversity was lower than vegetation diversity. The relatively high global diversity of tropical vegetation was found to be reflected in the pollen rain. KW - Neotropics KW - Palaeotropics KW - Palynology KW - Pollen trap KW - Forest-savannah KW - Savanna Y1 - 2018 U6 - https://doi.org/10.1007/s00334-017-0642-y SN - 0939-6314 SN - 1617-6278 VL - 27 IS - 2 SP - 411 EP - 418 PB - Springer CY - New York ER - TY - JOUR A1 - Rohrmüller, J. A1 - Kämpf, Horst A1 - Geiss, E. A1 - Grossmann, J. A1 - Grun, I. A1 - Mingram, Jens A1 - Mrlina, J. A1 - Plessen, Birgit A1 - Stebich, M. A1 - Veress, C. A1 - Wendt, A. A1 - Nowaczyk, Nobert T1 - Reconnaissance study of an inferred Quaternary maar structure in the western part of the Bohemian Massif near Neualbenreuth, NE-Bavaria (Germany) JF - International journal of earth sciences N2 - After a comprehensive geophysical prospecting the Quaternary MA 1/2 tina Maar, located on a line between the two Quaternary scoria cones Komorni could be revealed by a scientific drilling at the German-Czech border in 2007. Further geophysical field investigations led to the discovery of another geological structure about 2.5 km ESE of the small town Neualbenreuth (NE-Bavaria, Germany), inferred to be also a maar structure, being the fourth volcanic feature aligned along the NW-SE trending Tachov fault zone. It is only faintly indicated as a partial circular rim in the digital elevation model. Though not expressed by a clear magnetic anomaly, geoelectric and refraction seismic tomography strongly indicates a bowl-shaped depression filled with low-resistivity and low-velocity material, correlating well with the well-defined negative gravity anomaly of - 2.5 mGal. Below ca. 15 m-thick debris layer, successions of mostly laminated sediments were recovered in a 100 m-long sediment core in 2015. Sections of finely laminated layers, likely varves, rich in organic matter and tree pollen, were recognized in the upper (22-30 m) and lower (70-86 m) part of the core, respectively, interpreted as interglacials, whereas mostly minerogenic laminated deposits, poor in organic matter, and (almost) barren of tree pollen are interpreted as clastic glacial deposits. According to a preliminary age model based on magnetostratigraphy, palynology, radiocarbon dating, and cyclostratigraphy, the recovered sediments span the time window from about 85 ka back to about 270 ka, covering marine isotope stages 5-8. Sedimentation rates are in the range of 10 cm ka(-1) in interglacials and up to 100 cm ka(-1) in glacial phases. The stratigraphic record resembles the one from MA 1/2 tina Maar, with its eruption date being derived from a nearby tephra deposit at 288 +/- 17 ka, thus supporting the age model of the inferred Neualbenreuth Maar. KW - Eger Rift KW - Quaternary maar volcanism KW - Geophysical prospecting KW - Magnetostratigraphy KW - Palynology KW - Paleoclimate Y1 - 2018 U6 - https://doi.org/10.1007/s00531-017-1543-0 SN - 1437-3254 SN - 1437-3262 VL - 107 IS - 4 SP - 1381 EP - 1405 PB - Springer CY - New York ER - TY - JOUR A1 - Woutersen, Amber A1 - Jardine, Phillip E. A1 - Giovanni Bogota-Angel, Raul A1 - Zhang, Hong-Xiang A1 - Silvestro, Daniele A1 - Antonelli, Alexandre A1 - Gogna, Elena A1 - Erkens, Roy H. J. A1 - Gosling, William D. A1 - Dupont-Nivet, Guillaume A1 - Hoorn, Carina T1 - A novel approach to study the morphology and chemistry of pollen in a phylogenetic context, applied to the halophytic taxon Nitraria L.(Nitrariaceae) JF - PeerJ N2 - Nitraria is a halophytic taxon (i.e., adapted to saline environments) that belongs to the plant family Nitrariaceae and is distributed from the Mediterranean, across Asia into the south-eastern tip of Australia. This taxon is thought to have originated in Asia during the Paleogene (66-23 Ma), alongside the proto-Paratethys epicontinental sea. The evolutionary history of Nitraria might hold important clues on the links between climatic and biotic evolution but limited taxonomic documentation of this taxon has thus far hindered this line of research. Here we investigate if the pollen morphology and the chemical composition of the pollen wall are informative of the evolutionary history of Nitraria and could explain if origination along the proto-Paratethys and dispersal to the Tibetan Plateau was simultaneous or a secondary process. To answer these questions, we applied a novel approach consisting of a combination of Fourier Transform Infrared spectroscopy (FTIR), to determine the chemical composition of the pollen wall, and pollen morphological analyses using Light Microscopy (LM) and Scanning Electron Microscopy (SEM). We analysed our data using ordinations (principal components analysis and non-metric multidimensional scaling), and directly mapped it on the Nitrariaceae phylogeny to produce a phylomorphospace and a phylochemospace. Our LM, SEM and FTIR analyses show clear morphological and chemical differences between the sister groups Peganum and Nitraria. Differences in the morphological and chemical characteristics of highland species (Nitraria schoberi, N. sphaerocarpa, N. sibirica and N. tangutorum) and lowland species (Nitraria billardierei and N. retusa) are very subtle, with phylogenetic history appearing to be a more important control on Nitraria pollen than local environmental conditions. Our approach shows a compelling consistency between the chemical and morphological characteristics of the eight studied Nitrariaceae species, and these traits are in agreement with the phylogenetic tree. Taken together, this demonstrates how novel methods for studying fossil pollen can facilitate the evolutionary investigation of living and extinct taxa, and the environments they represent. KW - FTIR KW - LM KW - SEM KW - Paratethys KW - Tibet KW - Sporopollenin KW - Mediterranean KW - Steppe-desert KW - Australia KW - Palynology Y1 - 2018 U6 - https://doi.org/10.7717/peerj.5055 SN - 2167-8359 VL - 6 PB - PeerJ Inc. CY - London ER - TY - JOUR A1 - Klemm, Juliane A1 - Herzschuh, Ulrike A1 - Pestryakova, Luidmila Agafyevna T1 - Vegetation, climate and lake changes over the last 7000 years at the boreal treeline in north-central Siberia JF - Quaternary science reviews : the international multidisciplinary research and review journal KW - Tundra-taiga ecotone KW - Larix gmelinii KW - Palynology KW - Sediment geochemistry KW - Mean July temperature KW - Ordination KW - WA-PLS KW - Procrustes rotation Y1 - 2016 U6 - https://doi.org/10.1016/j.quascirev.2015.08.015 SN - 0277-3791 VL - 147 SP - 422 EP - 434 PB - Elsevier CY - Oxford ER -