Acta Palaeobotanica最新文献

{"title":"Holocene vegetation history of the Western Rhodope Mountains (South Bulgaria): the paleoecological record of peat bog Beliya Kanton","authors":"E. Marinova, M. Lazarova, D. Ivanov, S. Tonkov","doi":"10.35535/acpa-2023-0006","DOIUrl":"https://doi.org/10.35535/acpa-2023-0006","url":null,"abstract":"Pollen and plant macrofossil analyses supported with radiocarbon dating were conducted on a Holocene core from the peat bog Beliya Kanton (1547 m a.s.l.) located in the Western Rhodope Mountains (South Bulgaria). In the early Holocene until ~10 000 cal. BP the mountain slopes were covered by Pinus, admixed with Betula, Juniperus and shrubland of Ephedra among herb communities dominated by Poaceae, Cichorioideae, Achillea, Artemisia, Brassicaceae species. Subsequently, the afforestation continued with the expansion of broadleaved oak forests with Tilia, Ulmus and Corylus which reached their maximum distribution ~8800 cal. BP. Gradually, these forests began to retreat, replaced at many places first by Corylus and later on by Picea abies, Abies alba and Fagus. The formation of the contemporary coniferous belt with the dominance of Pinus – Picea abies and fragmented mixed coniferous-deciduous communities in the late Holocene was attributed not only to climate change but also to diverse human interference in the natural forest cover. During the last 2000 years the continuous presence of Juniperus, Juglans, Rumex, Cirsium, Plantago lanceolata and Hordeum pollen indicated intensive stock-breeding, grazing and crop cultivation. The fragments of charred wood testify to tree felling and fire clearances on flat ground to obtain new pasture land.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69872728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Endocarps of Parinari (Chrysobalanaceae) from the Neogene of Northeastern Thailand","authors":"P. Grote, J. Duangkrayom, Pratueng Jintasakul","doi":"10.35535/acpa-2022-0003","DOIUrl":"https://doi.org/10.35535/acpa-2022-0003","url":null,"abstract":"Five fossil endocarps were collected from late Miocene fluvial deposits in a commercial sandpit in Northeastern Thailand. The endocarps were studied with light microscopy and scanning electron microscopy (SEM) and compared with recent and fossil endocarps. We conclude that the endocarps are Parinari (Chrysobalanaceae) and propose two new species, P. hilliana and P. khoratensis. These provide the first record of Parinari fruits from Asia and the Pacific region and indicate that the genus was already pantropical by the Miocene with previous reports of Miocene Parinari endocarps from Africa (Ethiopia) and the Neotropics (Panama).","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49541765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Holocene vegetation dynamics and monsoonal climatic changes in Jammu, India","authors":"Md. Firoze Quamar","doi":"10.35535/acpa-2022-0004","DOIUrl":"https://doi.org/10.35535/acpa-2022-0004","url":null,"abstract":"Knowledge of the Holocene Indian Summer Monsoon (ISM) variability is important for understanding the spatio-temporal dynamics of the ISM precipitation. In this study, a Late Holocene pollen proxy record of the changes in the ISM intensity from a 1.8 m deep lacustrine sedimentary deposit in Jammu District (Jammu and Kashmir State) in India is presented. The results show that between ~3205 and 2485 cal yr BP, mixed broad-leaved/conifer forests occurred in the region under a warm and humid climate, probably indicating high monsoon precipitation. Subsequently, the conifers, such as Pinus sp., Cedrus sp., Abies sp., Picea sp. and Larix sp. increased comparatively and show dominance over the existing broad-leaved taxa between ~2485 and 1585 cal yr BP under a cool and dry climate with reduced monsoon precipitation. The climate further deteriorated (towards attaining aridity under reduced monsoon condition) during ~1585 to 865 cal yr BP, which coincides with the Dark Ages Cold Period (DACP: CE/AD 400–765; 1185–1550 cal yr BP). Since ~865 cal yr BP (CE/AD 1085 onwards) to Present, the broad-leaved taxa, such as Alnus sp., Betula sp., Ulmus sp., Carpinus sp., Corylus sp. and Quercus sp. started expanding and showed their dominance over the conifers, indicating a warm and humid climate in the region with increased monsoon precipitation. This phase partly corresponds with the Medieval Climatic Anomaly (MCA) between CE/AD 950 and 1300. Thus, the ISM rainfall intensity is linked with some of the global climatic trends in the present study.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48277559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Palynology of Early Cretaceous (Barremian to Aptian) hydrocarbon (methane) seep carbonates and associated mudstones, Wollaston Forland, Northeast Greenland","authors":"Emil Bang, H. A. Nakrem, C. Little, Wolfram M Kürschner, S. Kelly, M. Smelror","doi":"10.35535/acpa-2022-0002","DOIUrl":"https://doi.org/10.35535/acpa-2022-0002","url":null,"abstract":"Palynostratigraphic and palynofacies analysis have been performed on hydrocarbon seep carbonate, carbonate nodule and mudstone samples from the Early Cretaceous Kuhnpasset Beds in the Kuhnpasset area of Wollaston Forland, Northeast Greenland. Three informal palynostratigraphic zones have been defined based on dinoflagellate cyst occurrences. The zones range from ?early Barremian to early Aptian in age, and correlate with previously defined dinoflagellate cyst zones in Northeast Greenland. These zones indicate hydrocarbon seepage in Kuhnpasset spanned the ?early–late Barremian age range, but did not continue into the Aptian, and thus seep activity continued for as much as three million years. Palynofacies analysis is used to interpret the depositional environment of the Kuhnpasset Beds and indicate that the hydrocarbon seeps and associated mudstones from this sedimentary sequence were deposited in a proximal shelf setting.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46010014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Archaeobotanical evidence for the emergence of pastoralism and farming in southern Africa","authors":"J. Olatoyan, F. Neumann, E. Orijemie, C. Sievers, M. Evans, Sinethemba Mvelase, Tanya Hatting, M. Schoeman","doi":"10.35535/acpa-2022-0005","DOIUrl":"https://doi.org/10.35535/acpa-2022-0005","url":null,"abstract":"Several models which remain equivocal and controversial cite migration and/or diffusion for the emergence and spread of pastoralism and farming in southern Africa during the first millennium AD. A synthesis of archaeobotanical proxies (e.g., palynology, phytoliths, anthracology) consistent with existing archaeobotanical and archaeological data leads to new insights into anthropogenic impacts in palaeorecords. Harnessing such archaeobotanical evidence is viable for tracing the spread of pastoralism and farming in the first millennium AD because the impact of anthropogenic practices is likely to result in distinct patterns of vegetation change. We assess this impact through the synthesis of published archaeobotanical evidence of pastoralism and farming, as well as vegetation changes in southern Africa during the first millennium AD. It has been argued that the decline of forests during the first millennium AD in southern Africa predominantly relates to climate change. This argument often precludes anthropogenic effects on vegetation. Our reassessment of the relationship between vegetation, climate, and human activities in southern Africa reveals evidence of human impact during the same period. We also highlight gaps in the current knowledge of early pastoralism and farming and potential future research directions. We hypothesize that the pattern exhibited by the decline of forest tree pollen, coupled with the increase of open-land indicators, the occurrence of pioneer trees, as well as the spores of coprophilous fungi, and possible changes in the fire regime are reflective of, and consistent with, anthropogenic activities of pre-European pastoralists and farmers.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46109465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Loxopteroides weeksae gen. et sp. nov. (Anacardiaceae) samaras and associated foliage from the Eocene of western North America","authors":"S. Manchester, W. Judd","doi":"10.35535/acpa-2022-0001","DOIUrl":"https://doi.org/10.35535/acpa-2022-0001","url":null,"abstract":"An extinct kind of winged fruit found at several Eocene sites in California and Oregon, western USA, occurs in association with pinnately compound anacardiaceous leaves that have been called Rhus mixta. The samaras were previously treated along with isolated leaves from the Chalk Bluffs flora of California in an extinct sapindaceous genus, Thouiniopsis myricaefolia (Lesquereux) MacGinitie. However, the samaras are nonschizocarpic and hence readily distinguished from the mericarps of extant Sapindaceae such as Acer, Thouinia and Thouinidium. We reassign the fruits to Anacardiaceae and note similarity to the extant Neotropical genus Loxopterygium which differs, however, in the shape of the endocarp and placement of the style. Fruits of Loxopteroides weeksae gen. et sp. nov. co-occur with leaves of Rhus mixta at multiple localities in California and Oregon.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48730901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two-seeded cones of probable gnetalean affinity from the Morrison Formation (Late Jurassic) of Utah and Colorado, USA","authors":"S. Manchester, Xiaoqing Zhang, C. Hotton, S. Wing, P. Crane","doi":"10.35535/acpa-2022-0006","DOIUrl":"https://doi.org/10.35535/acpa-2022-0006","url":null,"abstract":"Three dimensional calcitic casts of a two-seeded compound cone are described from the Upper Jurassic Brushy Basin Member of the Morrison Formation based on specimens from Colorado and Utah. Cones of Bassitheca hoodiorum gen. et sp. nov. are broadly obovate in face view, ~3.5 mm high, ~2.6 mm wide, and viewed from above have two planes of symmetry. Micro-CT scanning of numerous specimens shows that each cone has two well-developed orthotropous seeds positioned opposite each other in the major plane and separated by a median longitudinal septum in the minor plane. At a higher level in the cone, a median apical septum in the major plane separates two depressions arranged opposite each other. The two well-developed seeds in the major plane are enclosed by bracts, but numerous incomplete cones, together with cones showing lines of dehiscence, indicate that each seed was shed by the abscission of a lateral valve. One specimen indicates that three vascular bundles entered the base of each well-developed seed and these are interpreted as the vascular supply to the envelope of a chlamydospermous ovule. The opposite and decussate arrangement of bracts at the base of the cone, the paired arrangement of the two well-developed seeds perpendicular to the two apical depressions, combined with the inferred seed envelope that was apparently shed with the seed, indicates a probable relationship to Gnetales and specifically to extant Ephedra. Along with Dayvaultia tetragona Manchester et Crane, also known from the Brushy Basin Member of the Morrison Formation, Bassitheca hoodiorum provides further evidence that the Gnetales were more significant in the Morrison vegetation than has been recognized previously.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69871513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pollen typification and palynotaxonomy of subfamily Salsoloideae Ulbr. (Chenopodiaceae Vent.) in the flora of South Transcaucasia","authors":"H. Sonyan, A. Hayrapetyan, Naira H. Poghosyan, A. Muradyan","doi":"10.35535/acpa-2022-0007","DOIUrl":"https://doi.org/10.35535/acpa-2022-0007","url":null,"abstract":"The article presents the results of a comparative palyno-morphological analysis of the representatives of the Salsoloideae subfamily (Chenopodiaceae) in South Transcaucasia. Out of 25 species belonging to 13 genera of Salsoloideae subfamily in South Transcaucasia, pollen morphology of 23 species from 12 genera was investigated, as well as an analysis of the pollen characteristics was conducted. Data on five key features of pollen (on LM level) were statistically analyzed including pollen diameter, pore number, pore diameter, exine thickness, and mesoporium width. The results indicated that within the Salsoloideae subfamily of South Transcaucasian flora the first three features may be considered diagnostic. The application of a scanning electron microscope (SEM) has revealed the fourth diagnostic feature of the pollen within the Salsoloideae subfamily, specifically, the number of spinules on the unit surface of the pollen, which enables, in several cases, to conduct intergeneric or interspecific differentiation. Based on the obtained data, typification of pollen within the Salsoloideae subfamily of South Transcaucasia was carried out for the first time. As a result, two morphological types and four subtypes combined in two palynogroups were distinguished. The subdivision into palynogroups is based on differences in the size of pollen grains. Only species Climacoptera crassa with pollen of average sizes (26–33/29 μm in diameter) is included into the monotypic Palynogroup I, all other investigated species with small pollen grains (10–25 (27)/22 μm in diameter) are joined in Palynogroup II. Allocation of species into two different Types of Palynogroup II is based on the presence of a significant difference in the size of small pollen grains of individual species. In particular, species with relatively large pollen grains (> 20 μm in diameter) are included in Type 1, while species with relatively small ones (≤ 20 μm in diameter) are joined in Type 2. And finally, the distribution of species into the subtypes and variations of Palynogroup II is based on differences in pore number and size. The identified key palyno-morphological features made it possible in some cases to specify the taxonomic boundaries, as well as the relationship between taxa within the subfamily Salsoloideae.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69872314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Graphic correlation and paleoenvironmental investigation of the upper Eocene–lower Oligocene sediments in the Dahomey Basin, southwestern Nigeria: insights from palynomorphs","authors":"M. Olayiwola, E. Durugbo,  . O. T. Fajemila","doi":"10.35535/acpa-2022-0011","DOIUrl":"https://doi.org/10.35535/acpa-2022-0011","url":null,"abstract":"This study presents the results of a comprehensive qualitative and quantitative palynological analysis of four shallow boreholes (Epe-1, Olokonla-1, Ikoyi-1 and Badore-1) in the lower Eocene–upper Oligocene periods of the Dahomey Basin, southwestern Nigeria. The lithostratigraphic analysis revealed three lithologies (sandy-shales, shaly-sands and sandstones). Two most important palynological zones, the Verrucatosporites usmensis, as well as the Magnastriatites howardi Pan-tropical zones, are delineated. First Appearance Datum (FAD) of Achomosphaera alcicornu marked the late Eocene–early Oligocene boundaries (E/O) within the four boreholes, while FAD of Adnatosphaeridium multispinosum defined the late Eocene–early Oligocene boundary (E/O) in Ikoy-1. Two informal palynological assemblage zones were revealed in the four boreholes. Common occurrences of palms, mangrove, fresh water and brackish water pollen, and pteridophyte spores with spots records of marine elements and algae species during marine invasion suggested fluctuation from fluvio-deltaic/nearshore to marginal marine paleoenvironments. Graphic correlation discloses that for every meter of sedimentary rock accretion within Epe-1, equally amounted to merely 0.31 m, 0.56 m, as well as 0.47 m of sediments, which were put down in Olokonla-1, Ikoyi-1, as well as Badore-1, respectively. These comparative rates of sedimentary rock accretion show with the purpose of either there is fewer attrition occurrence and/or extra accommodation gap within Epe-1 than Olokonla-1, Ikoyi-1, as well as Badore-1. The assessment of the slopes, intercept and correlation equations through graphic correlation procedures enable the identification of four biostratigraphic events in Epe-1, Olokonla-1, Ikoyi-1, as well as Badore-1. The findings in this investigation are necessary for depositional succession and paleoenvironmental understandings, as well as basin investigation, and above all, to show a relationship of broadly separated boreholes.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69872400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Devonian (Frasnian–Famennian) palynomorphs from the Padeha and Bahram Formations of Shahzadeh Mohammad section, northwest of Kerman, Iran","authors":"Roghayeh Rouzegar, P. Ozsvárt","doi":"10.35535/acpa-2022-0010","DOIUrl":"https://doi.org/10.35535/acpa-2022-0010","url":null,"abstract":"A diverse and well-preserved microphytoplankton assemblage is reported from a measured section of Frasnian–Famennian (Upper Devonian) Padeha and Bahram Formations in Shahzadeh Mohammad area, northwestern Kerman, southeast Iran. The palynoflora assemblage contains 17 genera and 23 species of acritarchs, chitinozoa, scolecodont and rich miospore taxa. 57 species (25 genera) of miospores were identified and 5 assemblage biozones were defined from the Shahzadeh Mohammad section. The miospore composition is similar to neighboring localities in Southern and Northern Iran, but it shows significant similarities with palynoflora from more distant localities, e.g. Saudi Arabia, Western Australia or Algeria. This implies a close relationship between the Iranian platform and other areas of the Northern Gondwana and southern Laurentia Domain during the late Devonian. The investigated section was deposited in a shallow marine environment with tropical conditions during the Frasnian-Famennian period.","PeriodicalId":39861,"journal":{"name":"Acta Palaeobotanica","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69872354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}