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在辽宁省葫芦岛地区的寒武系中发现了由Treptichnus pedum,Planolites montanus和Palaeophycus heberti构成的遗迹化石组合。Treptichnus pedum分布于馒头组上部石英细砂岩中,其特征符合曳鳃动物的摄食遗迹,说明曳鳃动物是当时这一地区底栖宏体动物群落的主要组成部分。结合该群落在整个华北地台广泛出现于馒头组上部的情况,其兴起可能是一次区域性底栖环境良化事件的结果。Planolites montanus和Palaeophycus heberti出现在张夏组上部中、薄层灰岩中,位于剖面上最早出现的一层风暴沉积和一中厚层叠层石之间,表明其形成时海盆水循环较好,水动力较强,底层水和底质氧气较为充足,适宜底栖生物的生存。 相似文献
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近几十年来,随着稳定性碳同位素和^14C测年等新技术,新方法的应用,使第四纪研究迅速地由定性向定量发展,然而,氨基酸应用于第四纪古生态和古气候的研究在国内仍少有人知,在国际期刊上也不多见。近年来,作者开展了长白山孤山屯和太湖全新世沉积物的氨基酸和有机碳同位素分布与古生态,古气候意义的分析研究,结果表明,化石氨基酸同样可为第四纪的生态环境和古气候的研究提供信息,并为全球性对比提供证据。 相似文献
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本文列举了大量具过顶古口缝的沟鞭藻囊孢在海相和非海相沉积中的记录,指出具有一构造的沟鞭藻囊孢可以细分成两个亚类,分别代表晚白垩世从海相澡类家族中分化出的两个分支:一个以Palaceperidinium为代表,具有bipesioid型反映板式;另一支以Saeptodinium为代表,具有bipesioid或cinctioid型反映板式,前者在晚白垩世开始向淡水环境迁移,但仍有部分留在海水中,一直延续 相似文献
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文中详细描述四川广安谢家槽剖面早三叠世地层中17个遗迹化石属,它们是:Arenicolites,Bifungites,Chondrites,Didymaulichnus,Isopodichnus,?Monocraterion,Palaeophycus,Phycodes,Planolites,Psammichnites,Skolithos,Taenidium,Teichichnus,Thalassinoides,Treptichnus,Uchirites和星状遗迹化石,它们可归属于Cruziana遗迹相。在风暴沉积中,Skolithos出现在主要的风暴沉积层,而Planolites和Palaeophycus常常出现在风暴序列的消减沉积层中。机会的遗迹化石如Treptichnus富集在纹层状灰岩中,指示一种贫氧的沉积环境。文中还探讨了遗迹化石在地层中的时空分布特点与P/Tr生物大灭绝后早三叠世海洋生物复苏的关系。 相似文献
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随着社会的进步、人们文化素质的提高,收藏古生物化石的人也越来越多了。在不少人的心目中,蚌壳、鱼、恐龙蛋、鸟类等似乎是化石王国的主要分子,这也不假,但古动物们行走留下的足迹、排泄的粪便等形成的化石在自然界中更为罕见。在大至恐龙、小至蠕虫、虾蟹的粪粒中,... 相似文献
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广西,贵州和川东二叠纪礁相岩石和礁后相岩层内获得了红藻Solenoporella,Gymnocodium,Permocalcu-lus;绿藻Anthracoporella,Mizzia以及显微疑难藻类化石Pseudovermiporella,Tubiphytes等,除了广西隆林有中二叠世茅口期藻类化石外,其它均属于晚二叠世乐平世的分子,这些藻类植物一般生活于热带和亚热带,正常盐度的浅海水内,其水深不大于30m,川东,鄂西晚二叠世礁属于浅水海绵礁,而非深水礁。 相似文献
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河南灵井许昌人遗址是我国近年来发掘的最为重要的古人类遗址之一。该遗址中出土了大量的石器、骨器、动物化石、粪便化石等遗存以及人类头盖骨化石等。我们对该遗址出土的鬣狗粪化石进行了类型学及其包含的微体化石等方面研究,从分析统计结果来看,鬣狗粪化石中包含了丰富的古信息,如古寄生虫卵、动物毛发、孢粉、植硅体、真菌等。本文主要针对鬣狗粪化石中古寄生虫卵及动物毛发进行分析,探讨了作为寄主鬣狗罹患的寄生虫病,以及鬣狗的食物来源等情况,为深入理解更新世晚期人类适应环境与气候提供新的证据。 相似文献
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记述了湘西北地区志留、泥盆系的遗迹化石14属,28种、亚种(包括15新种,2新亚种)。这些遗迹化石主要集中于Traueumichis-Arthrophycus群落(代表前滨下部或近滨上部),Thalassinoides-Lockeia群落(代表近滨上部或前滨下部环境)和Cruziana-Dimorphichnus群落(代表近滨环境),并对上述3个遗迹群落的古生态作了分析。 相似文献
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Integrated palaeoecological evidence for biodiversity at the floodplain-forest margin 总被引:2,自引:0,他引:2
This paper presents the results of a combined palynological and palaeoentomological investigation into the changing diversity of Holocene floodplain forest biota at Bole Ings in the lower reaches of the River Trent. The aim in combining the two techniques represents an attempt to overcome some of the inherent differences of scale and resolution which characterize different types of fossil species data. The two lines of ecofactual evidence, pollen and beetle remains indicate changes in the biodiversity of the floodplain, both in terms of the diversity and abundance of individual species, habitats and ecosystem structure. The results of the study demonstrate the potential of this approach in tracing the decline in plant and entomofaunal diversity at the floodplain forest margin. Although there are recognized limitations imposed by taphonomic uncertainties, taxonomic resolution and restricted ecological data, the combined results provide added details of variations in both species composition and structural diversity within the landscape. The results emphasize the need for multidisciplinary research design in palaeoecological investigations of biodiversity. 相似文献
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William Buckland not only was an eccentric scientist either liked or disliked by his peers but, in the early 1800s, was also the foremost authority on coprolites. The latter were a source of considerable amusement to some of his friends. 相似文献
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生物化石群落在埋葬过程中普遍经历了均时作用的过程。正是这种作用导致了同一生态环境域,但不同时期生物组合相混合的结果。因此,这种化石群落可能为一个连续演化群落的不同阶段的混合体,也可能是环境连续演化过程中不同生态群落的混合组合,这样的化石组合所记录的古生物学信息非常复杂。因此,对化石累积过程中的均时作用的清晰了解,将非常有助于古生物群落的分类学、居群动力学、埋葬学、古生态学、演化古生物学,甚至地层学研究精度的提高。文章根据前人的研究,扼要介绍和讨论均时作用的概念、过程、程度、效应和判别,及受均时作用影响的化石组合的分类。 相似文献
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Harnessing the potential of the multi‐indicator palaeoecological approach: an assessment of the nature and causes of ecological change in a eutrophic shallow lake 下载免费PDF全文
Helen Bennion Thomas A. Davidson Carl D. Sayer Gavin L. Simpson Neil L. Rose Jonathan P. Sadler 《Freshwater Biology》2015,60(7):1423-1442
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Suzette G. A. Flantua Ondrej Mottl Vivian A. Felde Kuber P. Bhatta Hilary H. Birks John-Arvid Grytnes Alistair W. R. Seddon H. John B. Birks 《Global Ecology and Biogeography》2023,32(8):1377-1394
Aim
Palaeoecological data are crucial for comprehending large-scale biodiversity patterns and the natural and anthropogenic drivers that influence them over time. Over the last decade, the availability of open-access research databases of palaeoecological proxies has substantially increased. These databases open the door to research questions needing advanced numerical analyses and modelling based on big-data compilations. However, compiling and analysing palaeoecological data pose unique challenges that require a guide for producing standardized and reproducible compilations.Innovation
We present a step-by-step guide of how to process fossil pollen data into a standardized dataset compilation ready for macroecological and palaeoecological analyses. We describe successive criteria that will enhance the quality of the compilations. Though these criteria are project and research question-dependent, we discuss the most important assumptions that should be considered and adjusted accordingly. Our guide is accompanied by an R-workflow—called FOSSILPOL—and corresponding R-package—called R-Fossilpol—that provide a detailed protocol ready for interdisciplinary users. We illustrate the workflow by sourcing and processing Scandinavian fossil pollen datasets and show the reproducibility of continental-scale data processing.Main Conclusions
The study of biodiversity and macroecological patterns through time and space requires large-scale syntheses of palaeoecological datasets. The data preparation for such syntheses must be transparent and reproducible. With our FOSSILPOL workflow and R-package, we provide a protocol for optimal handling of large compilations of fossil pollen datasets and workflow reproducibility. Our workflow is also relevant for the compilation and synthesis of other palaeoecological proxies and as such offers a guide for synthetic and cross-disciplinary analyses with macroecological, biogeographical and palaeoecological perspectives. However, we emphasize that expertise and informed decisions based on palaeoecological knowledge remain crucial for high-quality data syntheses and should be strongly embedded in studies that rely on the increasing amount of open-access palaeoecological data. 相似文献16.
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Learning from the past: Diatoms as palaeoecological indicators of changes in marine environments 总被引:2,自引:0,他引:2
The North Sea is seriously threatened by a variety of pollution sources. Terrestrially derived effluents are causing extensive
environmental damage and changes to ecosystems of both the offshore and coastal waters. Coastal and estuarine communities
are being lost to reclamation projects, and there is the future threat of rising sea level associaed with global warming.
The spatial and temporal extent of recent anthropogenic changes are largely unknown due to the paucity of background information.
The possible role of palaeoecological methodology in providing ‘reference levels’ against which current status can be compared,
and their importance for restoration and policy decisions, are presented. The usefulness of diatoms as environmental indicators
is illustrated. The extent of natural and anthropogenic changes on coastal habitats are demonstrated by reference to the Holocene
evolution of the coastline of The Netherlands. Possible profitable areas for further research are outlined,e.g. a diatom nutrient calibration data set for shallow marine embayments. 相似文献
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重金属在海洋食物链中的传递 总被引:36,自引:0,他引:36
近年来 ,金属在不同海洋食物链中摄食富集的定量研究得到越来越多的关注。自然环境中生物体内金属的浓度并不一定和生物在食物链中所处的营养级有相关关系 ,金属在生物体内的富集还受到生物的同化、排出等过程以及其它生理生化因子的影响。在经典的海洋浮游生物食物链中 (浮游植物→桡足类→鱼类 ) ,桡足类往往可以很有效地排出体内的金属 ,同时鱼类的金属同化率又很低 ,所以该食物链中金属的浓度随食物链水平增加而减少。目前研究发现只有甲基汞和铯 Cs会被食物链所放大。在以腹足动物为顶级捕食者的底栖食物链中 ,因为生物结合金属的效率很高 ,高同化率和低排出率导致金属浓度在生物体内得到放大。重金属在生物体内的可利用性可以通过测定同化率、排出率等参数、并结合考虑生物对该金属的消化行为 ,运用一个简易的动态模型来估算。已有的研究中人们多考虑金属的化学性质对食物链传递的影响。着重介绍了近年来国外对金属在不同海洋食物链 (底栖和浮游 )中的传递的研究成果 ,强调在金属的生物可利用性评估中 ,要充分考虑到动物的生理、生化过程的影响 ,同时也必须认识到不同的海洋生物有着复杂且不同的金属代谢机制 相似文献
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Davide Bassi Renato Posenato James H. Nebelsick Masato Owada Enrica Domenicali Yasufumi Iryu 《Historical Biology》2017,29(7):937-946
Random shell sections of the Pliensbachian (Early Jurassic) larger bivalve Opisoma from columns within the Main Post Office building of Ferrara, northern Italy, have been discovered to bear neat clavate-shape boreholes. These boreholes belong to the ichnogenus Gastrochaenolites Leymerie and represent bivalve borings. Opisoma is a subordinate component of the Lithiotis fauna characterised by aberrant shells thriving in tropical lagoonal settings which were widespread throughout the Tethyan and Panthalassa coasts. Although the Lithiotis fauna is well known in the palaeontological literature, no bivalve boring have been so far been formally described. The uniqueness of the morphology, size and substrate of these borings merits the designation of the new species Gastrochaenolites messisbugi ichnosp. nov. which thereby represents the first ichnospecies described from this fauna. The morphology of the boreholes and the included bivalves allows the boring activity to be ascribed to a mytilid bivalve. Palaeoecological and taphonomic analyses allowed the presence of the boreholes to be correlated to the Opisoma mode of life (epifaunal, free-living form) as well as to generally low sedimentation rates and seasonal mesotrophic conditions during an overall oligotrophic regime.
http://zoobank.org/urn:lsid:zoobank.org:act:CCF77B32-D459-4305-BC86-93F228852E50 相似文献