Review of Palaeobotany and Palynology最新文献

{"title":"A new approach to counting fossil and modern pollen grains: The orderly count","authors":"Tutku Tuncalı Yaman ,&nbsp;Bikem Ekberzade ,&nbsp;Hülya Caner ,&nbsp;Ruya Y. Dagdeviren ,&nbsp;Sena Inkaya ,&nbsp;Nurgul K. Kılıc ,&nbsp;Suzanne A.G. Leroy ,&nbsp;Fabienne Marret ,&nbsp;Cetin Senkul ,&nbsp;Jessie Woodbridge ,&nbsp;Meral Avci","doi":"10.1016/j.revpalbo.2024.105156","DOIUrl":"https://doi.org/10.1016/j.revpalbo.2024.105156","url":null,"abstract":"<div><p>Palynology, the study of pollen and spores, plays a crucial role in various scientific disciplines, including earth sciences (paleovegetation and paleoclimatology), botany, allergy, archaeology, forensic sciencs and cosmetics. This study delves into the critical question in fossil pollen analysis studies: the minimum count of pollen grains required for accurate estimation of vegetation composition. Various statistical methods have been proposed over the years to address this question. Our research introduces an alternative technique, the orderly count, tailored to the nature of palynological analysis. We apply this method to diverse sediment catchments, including peat bogs, marine and lake sediments, from different geographical locations. Additionally, we revisit the reliability coefficients and propose adjustments for more accurate results. Our findings suggest that relying on statistical methods without considering the specific characteristics of palynological data may lead to low reliability. We advocate for the integration of dissimilarity criteria and the orderly count in sample size assessments for enhanced accuracy in palynological analyses. Our study emphasizes the importance of choosing appropriate methodologies aligned with the unique aspects of palynology to ensure robust and reliable results.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141607401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tempskya hailunensis sp. nov. (Tempskyaceae), a new tree fern with preserved leaf-like structures, from the Cretaceous of the Songliao Basin, Northeast China","authors":"Feng-Xiang Liu ,&nbsp;Benjamin Bomfleur ,&nbsp;Philipp Hiller ,&nbsp;Xi Wang ,&nbsp;Xiao-Nan Yang ,&nbsp;Hai-E Du ,&nbsp;Dong-Wei Wang ,&nbsp;Yu-Jin Zhang ,&nbsp;Ye-Ming Cheng","doi":"10.1016/j.revpalbo.2024.105155","DOIUrl":"https://doi.org/10.1016/j.revpalbo.2024.105155","url":null,"abstract":"<div><p>A new tree fern of the family Tempskyaceae, <em>Tempskya hailunensis</em> sp. nov., is described herein based on a silicified trunk from the Cretaceous of Hailun City, Heilongjiang Province, Northeast China. The new species is composed of dichotomizing large stems surrounded by a mesh of adventitious roots, petioles, and leaf-like structures, constituting a solid and compact false trunk. The dorsiventral stems contain solenosteles that have long internodes with mostly two leaf traces. The stem cortex consists of a sclerenchymatous outer zone and a parenchymatous inner zone, and the stem pith is divided into a parenchymatous outer zone and a sclerenchymatous inner zone. Wide multicellular scales are attached to the stem epidermis. Leaf-like structures embedded among adventitious roots in the trunk are isobilateral, thick, and without distinct intercellular spaces. Also present are dispersed annuli of sporangia, which are only few cells long and apparently uniseriate. Though it cannot be fully ruled out that these vegetative and fertile remains belong to epiphytes that colonized the <em>Tempskya</em> trunk, the consistent and exclusive occurrence of these particular types of remains makes it likely that they belonged to the <em>Tempskya</em> plant itself. This new species represents only the second fossil record of <em>Tempskya</em> from China, increasing the known diversity of this genus during the Cretaceous both in Asia and globally. Moreover, it provided evidence for recognizing probable leaf structure and growth habit of <em>Tempskya</em>.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141607402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Callovian − Kimmeridgian palynology and palaeobiogeography of the Essaouira − Agadir Basin (Moroccan Atlantic Margin)","authors":"","doi":"10.1016/j.revpalbo.2024.105154","DOIUrl":"10.1016/j.revpalbo.2024.105154","url":null,"abstract":"<div><p>The Jurassic formations within the Essaouira<!--> <!-->−<!--> <!-->Agadir Basin are of considerable interest for petroleum exploration, owing to their reservoir facies and hydrocarbon potentiality. These formations exhibit a scarcity of macrofossils, and their age is determined through lithological correlation.</p><p>The Agadir<!--> <!-->−<!--> <!-->Essaouira Basin is a Mesozoic<!--> <!-->−<!--> <!-->Cenozoic sedimentary basin, part of the Tethyan Realm, precisely belonging to the Central Atlantic province which extends the Tethys westward. The material studied originates from five boreholes (GTE-1, MKL-110, NDK-2, NDK-3 and ESS-1) located at the center the basin along an East−West axis. The organic residue of the studied samples revealed a diverse dinoflagellate cyst assemblage with specific associations incorporating globally recognized marker taxa.</p><p>The Early Callovian is distinguished by species such as: <em>Ctenidodinium combazii</em>, <em>Ctenidodinium continuum, Ctenidodinium cornigerum</em>, <em>Dichadogonyaulax sellwoodii,</em> and <em>Impletosphaeridium varispinosum.</em> The Late Callovian is characterized by the presence of marker cysts including: <em>Compositosphaeridium polonicum, Endoscrinium galeritum Gonyaulacysta centriconnata, Liesbergia liesbergensis, Wanaea thysanota.</em> The Early Oxfordian is marked by the association of species including: <em>Gonyaulacysta jurassica</em> subsp. <em>jurassica</em>, <em>Rhynchodiniopsis cladophora</em>, <em>Scriniodinium crystallinum, Systematophora areolata</em>, <em>Systematophora penicillata</em>, and <em>Trichodinium scarburghense.</em></p><p>The Late Oxfordian to basal Kimmeridgian is characterized by an association of dinoflagellate cysts including: <em>Cribroperidinium globatum, Dichadogonyaulax? panneum, Downiesphaeridium polytrichum, Egmontodinium polyplacophorum, Endoscrinium galeritum</em>, <em>Gochteodinia mutabilis, Perisseiasphaeridium pannosum, Prolixosphaeridium anasillum, Scriniodinium crystallinum, Systematophora areolata, Systematophora penicillata, Surculosphaeridium vestitum, Systematophora? daveyi,</em> and <em>Wallodinium krutzschii.</em></p><p>Our associations have been correlated with those in contemporary basins within other paleogeographic realms, contributing to the formulation of a global paleobiogeographic pattern. This pattern complements previous research on the distribution of dinoflagellate cysts during the Callovian<!--> <!-->−<!--> <!-->Early Kimmeridgian time interval.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141703495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New record of Cretaceous Protocircoporoxylon wood from the Guyang Basin, northern China and its palaeoclimatic implications","authors":"Yeming Zhao ,&nbsp;Xiaohui Xu ,&nbsp;Liuyin Yang ,&nbsp;Chong Dong ,&nbsp;Cidan Zhongga ,&nbsp;Jiangxue Deng ,&nbsp;Xin Zhang ,&nbsp;Bo Zhang ,&nbsp;Gesang Zhuoma","doi":"10.1016/j.revpalbo.2024.105153","DOIUrl":"https://doi.org/10.1016/j.revpalbo.2024.105153","url":null,"abstract":"<div><p>Abundant and diversified Mesozoic fossil wood records have been reported in China. However, fossil woods have never been reported in the Guyang Basin, northern China. Here, a new calcified fossil wood specimen was discovered from the Lower Cretaceous Guyang Formation in the Guyang Basin. The present fossil are characterized by araucarian radial tracheid pitting and circopore cross-field pitting, typical of the genus <em>Protocircoporoxylon</em>. The specimen described here are mostly distinguishable from other fossil species of <em>Protocircoporoxylon</em> by the araucarian radial tracheid pitting and the number of pits per cross-field. Therefore, the present wood fossil is established as a new species, <em>Protocircoporoxylon guyangensis</em> Xu X.H. et Zhao Y.M. sp. nov. Up to now, the fossil detail records of <em>Protocircoporoxylon</em> have predominantly been found in the Triassic and Jurassic periods thus far. However, this discovery in Inner Mongolia, northern China indicates that the genus <em>Protocircoporoxylon</em> still into the Early Cretaceous period. The quantitative growth rings analysis of <em>P. guyangensis</em> sp. nov. indicates that it is an evergreen gymnosperm with a leaf retention time of 5–7 years. The fossil wood living in an environment with complacent water supply and weak seasonal fluctuations.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141487261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the Holocene rise, disturbance and decline of pine forests in the river valleys of northeastern Belgium using pollen and botanical macroremains","authors":"Annelies Storme ,&nbsp;Luc Allemeersch ,&nbsp;Ignace Bourgeois ,&nbsp;Philippe Crombé","doi":"10.1016/j.revpalbo.2024.105145","DOIUrl":"https://doi.org/10.1016/j.revpalbo.2024.105145","url":null,"abstract":"<div><p>The Holocene evolution of vegetation and environment in the Kleine Nete valley in the coversand region of northeastern Belgium is studied through sedimentological, palynological and macrobotanical analysis of a radiocarbon dated peat sequence. Peat formation started at the beginning of the Holocene in mesotrophic fen conditions. After a period of fast peat growth, the accumulation slowed down and the peat surface became dry in the Middle Holocene.</p><p>The palynological results are compared with other pollen data from the region, in order to establish a regional pollen biozonation for the Early and Middle Holocene in the Nete Basin. This shows that pine has long been a characteristic element in the Nete Basin. Pine forest expanded immediately after the 11.4 cold event, which is earlier than in the western Scheldt Basin. Pine and birch grew along the valley, possibly also within the peatland. Peaks of microcharcoal, herbs and/or coarse sediment in the peat reflect temporary local forest disturbances in the Early Holocene. Some may reflect small-scale controlled fires induced by hunter-gatherers, although a natural cause seems much more plausible given the dominance of fire-associated pines and increased drought. Pine remained important throughout the Early Holocene. This long-lasting predominance of pine in the Nete Basin, compared to elsewhere in the Scheldt Basin, is likely related to the poor sandy subsoil in the region, which hinders more nutrient-demanding broadleaf trees to overtake.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141487260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Palynostratigraphy and paleoenvironment of Upper Cretaceous sedimentary deposits from the Tarfaya-Laayoune-Boujdour-Dakhla Basin, southwestern Morocco","authors":"Khaoula Chafai ,&nbsp;Touria Hssaida ,&nbsp;wafaa Maatouf ,&nbsp;Hamid Slimani ,&nbsp;Ech-charqui Rjimati ,&nbsp;Abdelkrim Afenzar ,&nbsp;Abdelkarim Louaya ,&nbsp;Soukaina Jaydawi ,&nbsp;Sara Chakir ,&nbsp;Hanane Khaffou","doi":"10.1016/j.revpalbo.2024.105141","DOIUrl":"https://doi.org/10.1016/j.revpalbo.2024.105141","url":null,"abstract":"<div><p>Palynological investigations were carried out on Upper Cretaceous sediments from the three onshore sections, Tah, Amma Fatma and Oum Dbaa of the Tarfaya-Laayoune-Boujdour-Dakhla Basin, southwestern Morocco. 64 samples were collected for this palynological study, which yielded a very rich, diverse and well-preserved palynological content, including sporomorphs, prasinophytes, acritarchs, foraminiferal test linings and colonial fresh-water algae, dominated by dinoflagellate cysts comprising 141 species. The dinoflagellate cyst stratigraphic marker events used for the biostratigraphic interpretations include the first and last occurrences of stratigraphic marker species. The dinoflagellate cyst biostratigraphy allowed to assign the Amma Fatma section to the lower Turonian and the Tah section to the upper Campanian. The Oum Dbaa section is revised in detail and re-assigned to the upper Campanian–lowermost Maastrichtian. Analyses of the relative abundances of marine palynomorphs (mainly dinoflagellate cysts), as well as those of the palynofacies (amorphous organic matter, phytoclasts and palynomorphs) indicate two depositional settings alternating between a proximal inner shelf under suboxic-anoxic conditions and an outer neritic environment under dysoxic-anoxic conditions.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141483388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Filling the gap in the evolution of the genus Echinochara Peck (Clavatoraceae, Charophyta)","authors":"Jordi Pérez-Cano ,&nbsp;Carles Martín-Closas","doi":"10.1016/j.revpalbo.2024.105144","DOIUrl":"10.1016/j.revpalbo.2024.105144","url":null,"abstract":"<div><p><em>Echinochara</em> is a poorly known charophyte genus of the extinct family Clavatoraceae that thrived in the Middle Jurassic–Early Cretaceous of North America, Europe, and North Africa. It represents the most ancient and plesiomorphic genus of this family. However, the fossil record of <em>Echinochara</em> is discontinuous, showing several gaps, one of them especially significant in evolutionary terms between the Kimmeridgian and the early Barremian. The new species <em>Echinochara pontis</em> sp. nov., described here from the late Berriasian of the Maestrat Basin (NE Spain), bridges, in part, this gap, shedding light on the evolution of the genus during the earliest Cretaceous. The fructification (utricle) has bilateral symmetry, formed by two superimposed series of bract cells that abaxially cover the gyrogonite. The inner series has three long cells that are born by a short basal cell and reach the oospore apex. The outer series shows a central fan of bract cells, composed of a small basal cell, triangular in shape, that bears three long cells growing upwards, which are in turn flanked by two long bract cells on each side. The central basal cell and these two lateral cells are directly attached to the base of the utricle. The thallus is corticated with cells twisting at an angle of 30°. The utricle of <em>Echinochara pontis</em> displays a combination of features present in <em>Echinochara peckii</em> (Bathonian?–Kimmeridgian) and <em>Echinochara lazarii</em> (Barremian–early Aptian). For instance, the bilateral symmetry of the utricle and the morphology of the inner bract-cell series allow comparison with <em>E. lazarii</em>, whilst the morphology of the outer bract-cell series is closer to <em>E. peckii</em>. Moreover, the thallus of the new species shows cortical cells with a twisting angle intermediate between that of <em>Echinochara peckii</em> (40°–45°) and <em>Echinochara lazarii</em> (not twisted). The unique combination of morphological characters in the utricle of <em>Echinochara pontis</em> fits well with its intermediate chronostratigraphic position between the two former species. <em>Echinochara pontis</em> formed monospecific meadows in brackish settings. A preference for brackish settings is also observed for <em>Echinochara peckii</em> and in the older populations of <em>Echinochara lazarii</em>, suggesting that this habitat is probably a basal character in the evolution of the genus <em>Echinochara</em>.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0034666724000952/pdfft?md5=0f06a9682b37ec730f8799882b830d78&pid=1-s2.0-S0034666724000952-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141573773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Eocene–Oligocene vegetation and climate changes in southeastern Brazil","authors":"Thomas Kenji Akabane ,&nbsp;Maria Judite Garcia ,&nbsp;Andrea K. Kern ,&nbsp;Paulo Eduardo De Oliveira","doi":"10.1016/j.revpalbo.2024.105142","DOIUrl":"10.1016/j.revpalbo.2024.105142","url":null,"abstract":"<div><p>The Eocene–Oligocene Transition (EOT) marks the onset of a major phase of global cooling with significant consequences to the vegetation worldwide. Here, we present palynological analyses from a site in southern São Paulo basin, southeastern Brazil (23.67°S; 46.58°W). An Oligocene age was constrained by the abundance of <em>Dacrydiumites florinii</em> and <em>Podocarpidites</em> spp., alongside the presence of taxa such as <em>Cicatrocosisporites dorogensis</em> and <em>Polypodiisporites usmensis.</em> Autochthonous elements including <em>Paleoazolla, Corsinipollenites</em> spp.<em>, Monoporopollenites annulatus,</em> and Zygnemataceae algae spores are indicative of a low-energy freshwater depositional environment. In addition, we performed a comparison of Eocene and Oligocene temperature and precipitation estimates from records in southeastern Brazil using the weighted Mutual Climate Range approach. Results support global trends with a cooling of ca. 3–4 °C from the Eocene to the Oligocene accompanied by slightly drier regional conditions. Oligocene environmental changes drove a vegetation turnover by local extinction of warm-tropical taxa or a significant retreat of species unable to stand comparatively colder and drier climates under lower CO_2atm concentrations. Our data are consistent with previous estimates and verify the impact of global cooling on the vegetation of mid-low latitudes of the Southern Hemisphere.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141400852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new foliicolous fossil-species of Asterina Lév. (Asterinaceae; Asterinales) associated with Calophyllum L. from the Siwalik of Eastern Himalaya and its implications","authors":"Sumana Mahato,&nbsp;Mahasin Ali Khan","doi":"10.1016/j.revpalbo.2024.105143","DOIUrl":"10.1016/j.revpalbo.2024.105143","url":null,"abstract":"<div><p>The present study reports and describes a new foliicolous fossil-species of <em>Asterina</em> Lév. (Asterinaceae: Asterinales: Dothideomycetes) namely, <em>A. siwalika</em> sp. nov., on a compressed leaf assigned to modern <em>Calophyllum</em> L. (Calophyllaceae) recovered from the Siwalik sediments (early Miocene to Pliocene: Chunabati Formation) of Darjeeling, Eastern Himalaya. This epifoliar Siwalik fungal species is characterized by a dark brown, sub-dense mycelial mat; septate, branched, superficial, oppositely arranged hyphae with one to two-celled, alternate to oppositely arranged appressoria; flattened, circular, non-ostiolate thyriothecia, scutellum with radially arranged isodiametric to cylindrical cells; and bi-celled, one-septate, conglobate to ellipsoidal, striated ascospores. Here, we reconstruct for the first time a possible sexual life cycle of <em>A. siwalika</em>. The in-situ occurrence of <em>Asterina</em> on <em>Calophyllum</em> leaf cuticles suggests a warm and humid tropical climate and a possible host-parasitic relationship that might have existed in the ancient forest of the Darjeeling sub-Himalaya region during the time of deposition. The conclusion is supported by published qualitative and quantitative climatic data using plant megafossils recovered from the same fossil locality.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2024-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141393836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Late Oligocene flora of Aschudasty, Zaisan depression (East Kazakhstan)","authors":"A.L. Averyanova ,&nbsp;V.F. Tarasevich ,&nbsp;S.S. Popova ,&nbsp;T. Utescher ,&nbsp;V. Mosbrugger","doi":"10.1016/j.revpalbo.2024.105138","DOIUrl":"https://doi.org/10.1016/j.revpalbo.2024.105138","url":null,"abstract":"<div><p>The Late Oligocene is the time of the flourishing of typical warm temperate Turgay vegetation in Kazakhstan and adjacent areas. The Aschudasty flora described here originates from the Oshagandy Formation which correlates with the early part of the Chattian. The palaeobotanical analysis reveals 38 plant taxa, identified by macro- and microfloral remains related to Lycopodiophyta (1), Pteridophyta (3), Gymnospermae (7), Gnetophyta (1), Magnoliophyta (25) and plantae incerta sedis (1). Macrofossils include mainly Cupressaceae (<em>Metasequoia</em>, <em>Taxodium</em> and <em>Glyptostrobus</em>), Betulaceae (<em>Alnus, Corylus</em>) and <em>Ulmus</em>, as well as large number of monocots and aquatic ferns. The palynospectrum is dominated by pollen of the genus <em>Picea</em> (about 30%) and <em>Alnus</em> (about 40%), with noticeable amounts of pollen from other birch genera (about 7% in total). Plant functional type (PFT) and Coexistence Approach were used for palaeoenviromental reconstructions. Vegetation reconstruction shown that the microflora has a very temperate aspect reflecting a mixed deciduous conifer forest with a diverse, mainly deciduous shrub layer. The macroflora also reflects deciduous forest vegetation with conifers and possibly a very minor evergreen component. The climatic analysis shows a seasonal temperate climate. The pollen data reflect the zonal regional vegetation, the macroflora most probably reflects the lakeside wetland vegetation which may have experienced a warmer microclimate, compared to the upland realm. In whole significant climatic changes was not documented since Early Oligocene Rupelian time.</p></div>","PeriodicalId":54488,"journal":{"name":"Review of Palaeobotany and Palynology","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141322874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}