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The southern Central Andes–or Puna–now contains specialized plant communities adapted to life in extreme environments. During the middle Eocene (~40 Ma), the Cordillera at these latitudes was barely uplifted and global climates were much warmer than today. No fossil plant remains have been discovered so far from this age in the Puna region to attest to past scenarios. Yet, we assume that the vegetation cover must have been very different from what it looks today. To test this hypothesis, we study a spore-pollen record from the mid Eocene Casa Grande Formation (Jujuy, northwestern Argentina). Although sampling is preliminary, we found ~70 morphotypes of spores, pollen grains and other palynomorphs, many of which were produced by taxa with tropical or subtropical modern distributions (e.g., Arecaceae, Ulmaceae Phyllostylon, Malvaceae Bombacoideae). Our reconstructed scenario implies the existence of a vegetated pond surrounded by trees, vines, and palms. We also report the northernmost records of a few unequivocal Gondwanan taxa (e.g., Nothofagus, Microcachrys), about 5,000 km north from their Patagonian-Antarctic hotspot. With few exceptions, the discovered taxa–both Neotropical and Gondwanan–became extinct from the region following the severe effects of the Andean uplift and the climate deterioration during the Neogene. We found no evidence for enhanced aridity nor cool conditions in the southern Central Andes at mid Eocene times. Instead, the overall assemblage represents a frost-free and humid to seasonally-dry ecosystem that prevailed near a lacustrine environment, in agreement with previous paleoenvironmental studies. Our reconstruction adds a further biotic component to the previously reported record of mammals. [ABSTRACT FROM AUTHOR]

The plant fossil record of Bhavnagar is poorly documented despite its importance in understanding the evolution of Asian monsoonal ecosystems through time. Three genera of the families Fabaceae and Combretaceae are described from the Gaj Formation of Saurashtra Basin, Gujarat. The sediments of this formation are exposed around Lakhanka-Mithi Virdi villages in the Bhavnagar district of Gujarat and considered of early to middle Miocene in age. This is the first plant fossil record from the region of this age. The described fossil woods i.e. Hopeoxylon speciosum (Navale) Awasthi, Millettioxylon palaeopulchra Lakhanpal et al., and Terminalia tomentosa Wight and Arn. are found similar to the modern genera Sindora Miq., Millettia Wight & Arn (Fabaceae) and Terminalia L. (Combretaceae), respectively. The present distribution of modern comparable forms of the fossil taxa suggests existence of tropical to subtropical forests and warm and humid climatic conditions in the region during the Miocene in contrast to the sub-humid to dry climate seen today. [ABSTRACT FROM AUTHOR]

This article focuses on two areas of the European Unions's three-legged climate policy: the emissions trading and effort sharing sectors. The focus is on EU-level legislation, but examples of national frameworks where the EU's policy objectives are implemented are provided to highlight the practical implications of the legislation. The International Energy Agency has stated that carbon capture utilisation and storage (CCUS) will play an important role in reducing and removing CO2 emissions. This issue is topical as negotiations on updating the EU's climate targets and associated legislation are just being finalised. Furthermore, the EU Commission is defining rules for synthetic fuel production and regulation for certification of CO2 removals. EU policy favours utilising biogenic and atmospheric sources of CO2 over fossil sources for producing synthetic fuels in the long term. Currently, there are more incentives to store captured carbon from fossil fuel plants than biomass plants as carbon capture, utilisation and storage provides fossil installations a means of avoiding payment of allowances under the EU's emissions trading system. [ABSTRACT FROM AUTHOR]

Short-term hydrothermal scheduling problem plays an important role in maintaining a high degree of economy and reliability in power system operational planning. Since electric power generation from fossil fired plants forms a major part of hydrothermal generation mix, therefore their emission contributions cannot be neglected. Hence, multi-objective short term hydrothermal scheduling is formulated as a bi-objective optimization problem by considering (a) minimizing economical power generation cost, (b) minimizing environmental emission pollution, and (c) simultaneously minimizing both the conflicting objective functions. This paper presents a non-dominated sorting disruption-based oppositional gravitational search algorithm (NSDOGSA) to solve multi-objective short-term hydrothermal scheduling (MSHTS) problems and reveals that (i) the short-term hydrothermal scheduling problem is extended to a multi-objective short-term hydrothermal scheduling problem by considering economical production cost (EPC) and environmental pollution (EEP) simultaneously while satisfying various diverse constraints; (ii) by introducing the concept of non-dominated sorting (NS) in gravitational search algorithm (GSA), it can optimize two considered objectives such as EPC and EEP simultaneously and can also obtain a group of conflicting solutions in one trial simulation; (iii) in NSDOGSA, the objective function in terms fitness for mass calculation has been represented by its rank instead of its EPC & EEP values by using the NS approach; (iv) an elite external archive set is defined to keep the NS solutions with the idea of spread indicator; (v) the optimal schedule value is extracted by using fuzzy decision approach; (vi) a consistent handling strategy has been adopted to handle effectively the system constraints; (vii) finally, the NSDOGSA approach is verified on two test systems with valve point loading effects and transmission loss, and (viii) computational discussion show that the NSDOGSA gives improved optimal results in comparison to other existing methods, which qualifies that the NSDOGSA is an effective and competitive optimization approach for solving complex MSHTS problems. [ABSTRACT FROM AUTHOR]

The Lochkovian, Pragian, and basal part of the Emsian, which represent the post-Kwangsian Orogeny strata in the South China Block, are mainly composed of siliciclastic rocks. This lithological composition impedes investigation of Pragian and Lochkovian conodont biostratigraphy in the South China Block, which results in a persistent controversy on the age of relevant lithological units. The present study provides new evidence by reporting for the first time Lochkovian conodonts obtained from the South China Block, specifically the Gaoling Member of the Nahkaoling Formation at the Lingli section, central Guangxi. The conodont fauna, consisting of Pandorinellina exigua lingliensis Lu n. subsp., Pandorinellina exigua exigua, Zieglerodina? tuojiangensis Lu n. sp., Amydrotaxis praejohnsoni, and Eognathodus cf. E. irregularis, places the studied interval of the Gaoling Member in the lower or middle Lochkovian (contingent upon varying definitions for the base of the middle Lochkovian) to lower Pragian. Moreover, Amydrotaxis praejohnsoni, which was reported previously only in North America and eastern Australia, is herein also recorded in the South China Block, and thus may play an important role in intercontinental biostratigraphical correlation. By shedding light on the age of the upper limit of the underlying Lianhuashan Formation at the Lingli section, the present study indicates that the Kwangsian Orogeny ended before the late Lochkovian. This date is slightly earlier than the previously estimated late Lochkovian based on studies of fossil plants from the siliciclastic rocks deposited after the Kwangsian Orogeny. UUID: http://zoobank.org/8010f983-4f6f-43dd-949f-de4653e53d9d [ABSTRACT FROM AUTHOR]

Angiosperms are a group of plants with the highest rate of evolution, the largest number of species, the widest distribution and the strongest adaptability. Needless to say, angiosperms are the most important group for the humans. The studies on the origin, evolution and systematics of angiosperms have been the major challenges in plant sciences. However, the origin and early history of angiosperms remains poorly understood and controversial among paleobotanists. Some paleobotanists insist that there were no angiosperms in the pre-Cretaceous age. However, this conclusion is facing increasing challenges from fossil evidence, especially Early Jurassic Nanjinganthus, which is based on over two hundred specimens of fossil flowers. Studying more fossil plants is the only reliable way to elucidate the origin and early evolution of angiosperms. Here, we document a new species of angiosperms, Qingganninginfructus formosa gen. et sp. nov, and provide the first detailed three-dimensional morphology of Qingganninginfructus gen. nov from the Middle Jurassic of Northwest China. A Micro-CT examination shows that the best-preserved fossil infructescence has eleven samaroid fruits, each with a single basal ovule. Since these fossils are distinct in morphology and organization from all organs of known gymnosperms and angiosperms (the latter are defined by their enclosed ovules), we interpret Qingganninginfructus as a new genus of angiosperms including a new species, Q. formosa gen. et sp. nov., and an unspecified species from the Middle Jurassic of Northwest China. The discovery of this new genus of angiosperms from the Middle Jurassic, in addition to the existing records, undermines the "no angiosperms until the Cretaceous" stereotype and updates the perspective on the origin and early history of angiosperms. [ABSTRACT FROM AUTHOR]

Complete dinosaur footprint fossils are preserved on the surface of the fluvial and lacustrine sediments of Early Cretaceous Madongshan Formation in Liupanshan area of Ningxia, and the sporopollen is a good carrier to study the paleoclimate information of the time when dinosaurs lived. A systematic sporopollen study was carried out on the fossil occurrence profile of sauropod dinosaur footprints from Cretaceous Madongshan Formation in Qianzhuang village of Longde county, Liupanshan area. A total of 41 genera and 63 species of sporopollen were identified. It is divided into 3 sporopollen assemblages from bottom to top of the profile, including Bisaccates-Jiaohepollis assemblage, Classopollis-Jiaohepollis-Cicatricosisporites assemblage and Cicatricosisporites-Foraminisporis assemblage. The geological age reflected by the characteristics of the sporopollen assemblage is Early Cretaceous Aptian-Albian period. The established vegetation of dinosaurs footprint fossils has undergone a transition from conifers to cypresses, and then to ferns. Further research suggests that the paleoclimate in the age of dinosaurs experiences a change from subtropical subhumid climate to subtropical warm and semi-arid climate, and then to subtropical humid climate. This is consistent with previous research conclusions on sedimentary paleoclimatic environment of Cretaceous Madongshan Formation in Liupanshan area. [ABSTRACT FROM AUTHOR]

The global temperature gradually decreased from the Cretaceous Santonian to Campanian, while angiosperms evolved rapidly and gradually became dominant. The Songliao Basin, NE China, contains abundant fossil palynomorphs from the Santonian to Campanian age. A thorough investigation of fossil palynomorphs in borehole ZKY2-1 of the SW Songliao Basin was performed, reconstructing the vegetation and paleoclimate transition from the Santonian–earliest Campanian (lower Nenjiang Formation) to the late Campanian (Sifangtai Formation). Eighty form-genera from borehole ZKY2-1 have been identified. Three palynomorph assemblages were identified: the Schizaeoisporites–Cyathidites–Inaperturopollenites assemblage, Schizaeoisporites–Classopollis–Retitricolporites assemblage, and Schizaeoisporites–Aquilapollenites–Tricolporopollenits assemblage, from bottom to top. Based on palynological analysis from ZKY2-1 and other boreholes in the Songliao Basin, angiosperm pollen proportion in the Sifangtai Formation is significantly higher than in the lower Nenjiang Formation, indicating rapid angiosperm spread from late Santonian to Campanian. Palynological records indicate relatively humid climate during this period; the content of cool palynological types increased from the lower Nenjiang Formation to the Sifangtai Formation, suggesting a transition from warm to cool climate during the late Santonian–earliest Campanian to the late Campanian. The new palynological evidence from the Songliao Basin reveals a global cooling on land and sea during the late Santonian–Campanian period. This climate change may further promote angiosperm spread during the Late Cretaceous period. [ABSTRACT FROM AUTHOR]

Oriented samples were collected in the southern Mongolia Plateau and north‐eastern Tibetan Plateau to detect links between microstructural features, which are inferred from magnetic fabrics, and outcrop‐scale sedimentary structures that include slender fossil orientations. Palaeocurrent imprints in particles and their recognition in magnetic fabrics depend on the kinetics of current and any post‐depositional reworking. Here, we restored the flooding palaeocurrent direction through the statistical orientation of slender fossils and imprints indicated by magnetic fabric patterns in the sediments. We found that the tilt response of the minimum susceptibility axes preserves more links to the dynamic orientation of fossil deposits, while the maximum susceptibility axes may be easily reworked by a weak but long‐term tectonic compression. Comparing the two methods reveals the correlation between fossil distribution and magnetic fabric. The dynamic identification of anisotropy of magnetic susceptibility on large quantitative samples contributes to provide an alternative way for further statistics of fine‐grained sediments and fabric arrangement. [ABSTRACT FROM AUTHOR]

Biogeographic disjunction patterns, where multiple taxa are shared between isolated geographic areas, represent excellent systems for investigating the historical assembly of modern biotas and fundamental biological processes such as speciation, diversification, niche evolution, and evolutionary responses to climate change. Studies on plant genera disjunct across the northern hemisphere, particularly between eastern North America (ENA) and eastern Asia (EAS), have yielded tremendous insight on the geologic history and assembly of rich temperate floras. However, one of the most prevalent disjunction patterns involving ENA forests has been largely overlooked: that of taxa disjunct between ENA and cloud forests of Mesoamerica (MAM), with examples including Acer saccharum, Liquidambar styraciflua, Cercis canadensis, Fagus grandifolia, and Epifagus virginiana. Despite the remarkable nature of this disjunction pattern, which has been recognized for over 75 years, there have been few recent efforts to empirically examine its evolutionary and ecological origins. Here I synthesize previous systematic, paleobotanical, phylogenetic, and phylogeographic studies to establish what is known about this disjunction pattern to provide a roadmap for future research. I argue that this disjunction pattern, and the evolution and fossil record of the Mexican flora more broadly, represents a key missing piece in the broader puzzle of northern hemisphere biogeography. I also suggest that the ENA–MAM disjunction represents an excellent system for examining fundamental questions about how traits and life history strategies mediate plant evolutionary responses to climate change and for predicting how broadleaf temperate forests will respond to the ongoing climatic pressures of the Anthropocene. [ABSTRACT FROM AUTHOR]

We present the first description of Jurassic vertebrate fossils from Texas. The vertebrate specimens were collected from the Upper Jurassic Malone Formation in the Malone Mountains of western Texas. The specimens are fragmentary and not particularly diagnostic, but probably represent elements of plesiosaurians. One specimen is similar to the caudal vertebra of a pliosaurid plesiosaurian, whereas another may be a partial propodial of a small plesiosaurian. Additional bone fragments are not identifiable at this time. These vertebrates were discovered along with abundant plant and invertebrate fossils. Previous studies of the invertebrate fossils indicate a Kimmeridgian to Tithonian age for the Malone Formation, which is consistent with a single grain age of 151± 2 Ma from detrital zircon U--Pb geochronology obtained in this study. The Malone Formation was deposited in shallow marine to marginal marine environments along the northern edge of the Chihuahua trough. It is correlative with the La Casita and La Caja Formations of northern Mexico, where similar marine vertebrates have been reported. The Malone Formation is also correlative with the Morrison Formation to the north. [ABSTRACT FROM AUTHOR]

Animals breaking away from the sea was a revolutionary event in the evolution of life. Arthropods were the earliest metazoans to move onto land, and although a few Silurian freshwater and/or terrestrial arthropods have been found so far, these records are all from Laurussia. Here, we describe a new freshwater arthropod, Maldybulakia saierensis sp. nov., from the western Junggar, northwest China. Evidence from co‐occurring spores and body fossils of plants is presented in support of a Silurian (Pridoli) age for this new Maldybulakia species, alongside palaeosalinity data in support of our interpretation of it having lived in a freshwater environment. The discovery of this species brings forward the earliest appearance of the Maldybulakia, previously known from the Devonian of Kazakhstan and eastern Australia, to the late Silurian. It is the oldest body fossil record of a putatively freshwater arthropod outside Laurussia, and greatly expands their palaeogeographical distribution. In the middle and late Silurian, the discovery of freshwater arthropods on multiple plates/terranes, as well as their morphological diversity during this period, suggests that arthropods had left the marine environment by the early Silurian or even earlier. [ABSTRACT FROM AUTHOR]

Precisely how to reconstruct the planetary past is not predetermined. This article compares three contemporary plans, dreamed up in the United States during the Interwar and Depression years, that deploy diverse techniques to evoke extinct environments. Building on Martin Rudwick's historicization of 'scenes from deep time', this article develops the concept of designs on deep time to explain how public displays of the planetary past circulate anything-but-neutral ideas about past and present to awed audiences. By detailing three contemporary designs on deep time—Pleistocene Park at the La Brea Tar Pits, a sensational World's Fair exhibit called 'The World a Million Years Ago', and a dinosaur park where living fossils and ancient plants approximated a Mesozoic atmosphere—this article captures diverse philosophies about how to construct persuasive encounters with the prehistoric past. It also demonstrates how, despite disparate approaches, these designers of deep time displays all used the planetary past to legitimate present regimes and foster faith in human progress. During the 1920s and 1930s, when the wounds of war, changing demographics, and economic depression collaborated to dispute a prevailing myth of American progress, deep time by design buoyed faith in a better future. [ABSTRACT FROM AUTHOR]

This paper relies on an incidence of environmental disaster to examine the specific objective of a regulatory agency. Leveraging the Tennessee Valley Authority's Kingston Fossil Plant coal ash spill of 2008 as a natural experiment, I compare the public interest theory of regulation—maximization of net social benefits—with public choice theory, which here is the maximization of net political support. I estimate the effect of the environmental disaster on Clean Water Act monitoring in Tennessee to test one posited objective against the other. I find that regulated facilities proximate to the spill are subject to closer state-administered monitoring after the spill than regulated facilities away from the spill, even though the additional wastewater inspections do not produce positive marginal benefits for controlling coal ash. Additionally, the difference in monitoring soon normalizes to pre-spill levels, consistent with the public's interest in the event. The empirical results supply evidence that the studied regulatory agency maximizes net political support. [ABSTRACT FROM AUTHOR]

Excavation of a green breccia lens in the otherwise shaley Hudspeth Formation of central Oregon recovered a surprising variety of fossils of different kinds: plant impressions, mollusc shells, and vertebrate bones and teeth. Some ammonites, such as Mortoniceras inflatum, which date the deposit as late Albian (103 Ma), were preserved with shell intact below, but dissolved above back to sutures. Intact ammonites were outnumbered by angular ammonite fragments in the size range 1–2 cm. Marine clams, snails and ammonites were found in the same bed as a variety of fossil plants, including horsetails, ferns, cycads, and conifers. Also recovered were bones of fish, ichthyosaurs, dinosaurs, and pterosaurs. Orientation of large fossil logs and branches reveal derivation from the east, where a shoreline of shingle beaches and alluvial fans created the interfingering Gable Creek Conglomerate. The matrix-supported green breccia is massive and ungraded, and interpreted as a mass flow deposit. Enrichment in phosphorus compared with shale above and below is evidence that its fine-grained component includes guano. This guano and unusual fragmentation of ammonites are interpreted as evidence that the Oregon pterosaur, Bennettazhia oregonensis, was a mollusc-eater and formed large colonies on nearby cliffs, like modern gull rookeries. [ABSTRACT FROM AUTHOR]

Plant fossils play an important role in understanding landscape evolution across the Tibetan Region, as well as plant diversity across wider eastern Asia. Within the last decade or so, paleobotanical investigations within the Tibet Region have led to a paradigm shift in our understanding of how the present plateau formed and how this affected the regional climate and biota. This is because: (1) Numerous new taxa have been reported. Of all the Cenozoic records of new plant fossil species reported from the Tibet (Xizang) Autonomous Region 45 out of 63 (70%) were documented after 2010. Among these, many represent the earliest records from Asia, or in some cases worldwide, at the genus or family level. (2) These fossils show that during the Paleogene, the region now occupied by the Tibetan Plateau was a globally significant floristic exchange hub. Based on paleobiogeographic studies, grounded by fossil evidence, there are four models of regional floristic migration and exchange, i.e., into Tibet, out of Tibet, out of India and into/out of Africa. (3) Plant fossils evidence the asynchronous formation histories for different parts of the Tibetan Plateau. During most of the Paleogene, there was a wide east-west trending valley with a subtropical climate in central Tibet bounded by high (>4 km) mountain systems, but that by the early Oligocene the modern high plateau had begun to form by the rise of the valley floor. Paleoelevation reconstructions using radiometrically-dated plant fossil assemblages in southeastern Tibet show that by the earliest Oligocene southeastern Tibet (including the Hengduan Mountains) had reached its present elevation. (4) The coevolution between vegetation, landform and paleoenvironment is evidenced by fossil records from what is now the central Tibetan Plateau. From the Paleocene to Pliocene, plant diversity transformed from that of tropical, to subtropical forests, through warm to cool temperate woodland and eventually to deciduous shrubland in response to landscape evolution from a seasonally humid lowland valley, to a high and dry plateau. (5) Advanced multidisciplinary technologies and novel ideas applied to paleobotanical material and paleoenvironmental reconstructions, e.g., fluorescence microscopy and paleoclimatic models, have been essential for interpreting Cenozoic floras on the Tibetan Region. However, despite significant progress investigating Cenozoic floras of the Tibetan Region, fossil records across this large region remain sparse, and for a better understanding of regional ecosystem dynamics and management more paleobotanical discoveries and multidisciplinary studies are required. [ABSTRACT FROM AUTHOR]

The Registration Committee was established at the Nomenclature Section of the XIX International Botanical Congress (IBC) in Shenzhen, China in 2017. It followed the previous Special Committee on Registration of Algal and Plant Names (including fossils). A clear majority of Registration Committee members support having named taxa associated with a unique universal digital identifier in order to secure and facilitate the exchange of information by electronic means. However, discussions within the Committee showed that mandatory referencing of a unique universal digital identifier was not a solution. The Committee recommends that authors provide nomenclatural repositories with a reference to an actual and current publication for indexing purposes, or to register voluntarily. [ABSTRACT FROM AUTHOR]

Changes in terrestrial vegetation during the mid-Cretaceous and their link to climate and environmental change are poorly understood. In this study, we use plant macrofossils and analysis of fossil pollen and spores from the Western Desert, Egypt, to assess temporal changes in plant communities during the Cenomanian. The investigated strata have relatively diverse sporomorph assemblages, which reflect the nature of parent vegetation. Specifically, the palynofloras represent ferns, conifers, monosulcate pollen producers, Gnetales, and a diverse group of angiosperms. Comparisons of both, dispersed palynoflora and plant macrofossils reveal different characteristics of the palaeoflora owing to a plethora of taphonomical and ecological biases including the depositional environment, production levels, and discrepancies between different plant organs. A combination of detailed records of sporomorphs, leaves, and charcoal from the studied successions provide new understandings of the palaeoclimate and palaeogeography during the Cenomanian and Albian-Cenomanian transition in Egypt. The mixed composition of the palynofloral assemblages reflects the presence of different depositional situations with a weak marine influence, as evidenced by a minor dinoflagellate cysts component. The local vegetation comprised various categories including herbaceous groups including ferns and eudicots, fluvial, open environments, and xeric arboreal communities dominated by Cheirolepidiaceae and perhaps including drought- and/or salt-tolerating ferns (Anemiaceae) and other gymnosperms (Araucariaceae, Ginkgoales, Cycadales, and Gnetales) as well as angiosperms. The presence of riparian and freshwater wetland communities favouring aquatic and/or hygrophilous ferns (of Salviniaceae and Marsileaceae), is noted. The wide variation of depositional settings derived from the palynological data may be attributed to a prevalent occurrence of producers in local vegetation during the early Cenomanian of Egypt. For the purpose of this work on the studied Bahariya Formation and its equivalent rock units, where iconic dinosaurs and other fossil fauna roamed, we attempt to improve the understanding of Egypt's Cenomanian climate, which is reconstructed as generally warm and humid punctuated by phases of considerably drier conditions of varying duration. [ABSTRACT FROM AUTHOR]

The Wietrzychowice Cultural Park protects one of the last preserved megalithic barrows constructed by the Funnel Beaker Culture societies at the Kuyavia Lakeland (Central Poland). The nearby archaeological site at Śmieły located on the shore of Karaśnia Lake provided numerous Mesolithic and Neolithic remains such as flint artefacts, potsherds, arrowheads, and mammal bones with traces of human processing. The lake and peat sediments at the Śmieły site provided a unique opportunity to investigate man-environment relationships during the transition period from Mesolithic to Neolithic. The age-depth model for the deposits was based on five radiocarbon dates as well as archaeological artefacts. The multi-proxy study, including geochemistry, pollen, plant macrofossils, Mollusca, Cladocera and Chironomidae analyses, were conducted to recognize palaeoenvironmental changes between 7500 and 3500 BCE. Combining environmental and archaeological data, we attempt to distinguish between natural phenomena triggered by climate factors with those induced by human activity. The data indicated hydrological changes associated with natural factors: (1) the phase of aquatic ecosystem since 7500 to 5800 BCE, (2) the phase of water shallowing between 5800 and 4600 BCE, and (3) the development of alder fen in the lake shore zone since ca. 4600 BCE. Vegetation changes suggest early landscape transformations in Central Poland already due to the activity of Mesolithic societies. Fossil pollen and plant macroremains data combined with detailed map of modern soil distribution in the area allowed to identify pattern of vegetation distribution around the Mesolithic campsite. Neolithic discontinuity of habitation process between ca. 4600 and 4000 BCE (in the times of Brześć Kujawski Group of Lendyel Culture) can be associated with climate change resulting in Karaśnia Lake level lowering. [ABSTRACT FROM AUTHOR]

The Early Jurassic angiosperm Nanjinganthus has triggered a heated debate among botanists, partially due to the fact that the enclosed ovules were visible to naked eyes only when the ovary is broken but not visible when the closed ovary is intact. Although traditional technologies cannot confirm the existence of ovules in a closed ovary, newly available Micro-CT can non-destructively reveal internal features of fossil plants. Here, we performed Micro-CT observations on three dimensionally preserved coalified compressions of Nanjinganthus. Our outcomes corroborate the conclusion given by Fu et al., namely, that Nanjinganthus is an Early Jurassic angiosperm. [ABSTRACT FROM AUTHOR]

Palaeoflora in Pakistan in the Miocene is characterized by its high biodiversity. The present study investigated the pollen of fossil plants from the Murree Formation of Pakistan. Shales and mudstones were collected from the Murree section located at the foothills of the Margalla hills and analyzed by palynofacies and palynostratigraphic analyses. In this paleopalynological study of the Miocene Murree Formations of Pakistan, 31 samples were analyzed using microscopic techniques containing 48 pollen types from 12 families. The quantitative and qualitative morphological features of pollen were determined using light and scanning electron microscopy to help identify the pollen grains. Exine ornamentations and spines were the most important diagnostic features for distinguishing one pollen grain from another. The maximum exine thickness was observed in Ocimum basilicum of 4.25 μm, whereas the maximum pollen diameter was recorded for Pinus of 69.5 μm. Lamiaceae, Asteraceae, and Poaceae were the dominant families. The results showed that the preservation of floral records was not optimal. The presented results provide data on the dominant fossil plant taxa that existed in Pakistan (23.03–5.33 Ma). The evolution and phytogeographical histories of fossil plants can be unraveled using rock sediments to preserve biodiversity. [ABSTRACT FROM AUTHOR]

Although diverse fossil angiosperms (including their reproductive organs) have been reported from the Early Cretaceous, few of them are well-documented due to poor preservation and limited technologies available to apply. For example, paraffin sectioning, a routine technology applied to reveal the anatomical details of extant plants, was hitherto at most rarely applied to fossil plants. This undermines the comparability between the outcomes of studies on fossil and extant plants, and makes our understanding on plants incomplete and biased. Here, we applied paraffin sectioning technology, in addition to light microscopy, SEM, and TEM, to document a fossil reproductive organ, Xilinia gen. nov., from the Early Cretaceous in Inner Mongolia, China. The anatomical details of this new reproductive organ were documented. Xilinia bears a remarkable resemblance to conifer cones, although its ovules are enclosed in carpels. The paradoxical cone-like morphology of Xilinia appears to represent a transitional snapshot of plant evolution that is absent in extant plants. [ABSTRACT FROM AUTHOR]

The use of the functional feeding group–damage type system for analyzing arthropod and pathogen interactions with plants has transformed our understanding of herbivory in fossil plant assemblages by providing data, analyses, and interpretation of the local, regional, and global patterns of a 420-Myr history. The early fossil record can be used to answer major questions about the oldest evidence for herbivory, the early emergence of herbivore associations on land plants, and later expansion on seed plants. The subsequent effects of the Permian–Triassic ecological crisis on herbivore diversity, the resulting formation of biologically diverse herbivore communities on gymnosperms, and major shifts in herbivory ensuing from initial angiosperm diversification are additional issues that need to be addressed. Studies ofherbivory resulting from more recent transient spikes and longer-term climate trends provide important data that are applied to current global change and include herbivore community responses to latitude, altitude, and habitat. Ongoing paleoecological themes remaining to be addressed include the antiquity of modern interactions, differential herbivory between ferns and angiosperms, and origins of modern tropical forests. The expansion of databases that include a multitude of specimens; improvements in sampling strategies; development of new analytical methods; and, importantly, the ability to address conceptually stimulating ecological and evolutionary questions have provided new impetus in this rapidly advancing field. [ABSTRACT FROM AUTHOR]

Fossilized plant remains have been studied simultaneously by laser induced fluorescence and Raman spectroscopies, to reveal the prospective methods for onsite or/and laser remote sensing in future extraterrestrial missions. A multiwavelength instrument, capable of fluorescence and Raman measurements, has been utilized for the study of isolated plant fossils, as well as fossils associated with sedimentary rocks. Laser-induced fluorescence spectroscopy revealed that plant fossils and rocks' luminosity differed significantly due to chlorophyll derivatives (chlorin, porphyrins, lignin components etc.); therefore, fossilized plants can be easily detected at rock surfaces onsite. Raman spectroscopy highly altered the fossilized graphitic material via the carbon D and G bands. Our results demonstrated that combined laser-induced fluorescence and Raman spectroscopy measurements can provide new insights into the detection of samples with biogenicity indicators such as chlorophyll and its derivatives, as well as kerogenous materials. The prospects of multiwavelength LIDAR instrument studies under fieldwork conditions are discussed for fossils diagnostics. The method of laser remote sensing can be useful in geological exploration in the search for oil, coal-bearing rocks, and rocks with a high content of organic matter. [ABSTRACT FROM AUTHOR]

A large, broadly elliptical coccolith of the genus Similiscutum (Biscutaceae) was observed in sediments dated from the Lower Jurassic (upper Pliensbachian to Toarcian) coming from different localities of western Tethys, namely Portugal (Lusitanian Basin), France (Causses and Paris basins) and Spain (Subbetic area). This form is quite easy to find in the Toarcian GSSP (Global Stratotype Section and Point) of Peniche (Portugal), where the holotype has been described. More than 100 specimens of Similiscutum were digitally captured using a CCD camera, including this large form and two other related species, Similiscutum finchii and Similiscutum novum. The length and width of the coccoliths and the length and width of their central area were measured, and biometric analyses were performed. Results show that this large morphotype of Similiscutum is well characterized and easily differentiable by its size and morphology from the species S. finchii and S. novum, which are characterized by a similar extinction pattern in optical-microscope crossed polars. On the basis of combined differences in size and in central-area shape and structure, Similiscutum giganteum sp. nov. is introduced here. (Plant Fossil Names Registry no.: PFN003067; Act LSID: urn:lsid:plantfossilnames.org:act:3067). [ABSTRACT FROM AUTHOR]

The mid-Holocene is generally regarded as a relatively warm period, and therefore reconstructing land cover change from the mid-Holocene onwards may help predict future changes under warming scenarios. In this study, we used a new strategy which combines the REVEALS model with modern analogue technique (MAT) to achieve a land cover reconstruction since 6 ka BP for Northwest (NW) China. The REVEALS results are more consistent with our general understanding of pollen-vegetation relationships in NW China than the pollen percentage data. However, although the model has potential for future applications, further quantitative testing is needed. Modern calibration sets can provide modern "analogues" for most of the fossil samples, but the numbers of modern samples from areas with a low vegetation cover are limited, which may lead to over- or underestimation of the results, despite the overall small prediction error. Our land cover results show that, since ∼6 ka BP, the vegetation cover in mountains areas was significantly greater than at lower elevations, with the threshold cover value of 45%. At lower elevations, the vegetation cover gradually decreased from east to west. Elevation differences and the distance from the sea may be the main reasons for the differences. The mountains were dominated by steppe, meadow/meadow steppe, and forest, while the lower elevations were dominated by desert and desert steppe, with generally only small changes in vegetation type, reflecting the long-term arid climatic background of the region. However, since ∼6 ka BP there were several differences in the pattern of dry-wet climate shifts across the study region. The vegetation in most areas indicates a trend towards wetter conditions, or no significant trend, except for sites G1 and G3 which show an aridification trend. [ABSTRACT FROM AUTHOR]

The emergence of forests on Earth (~385 million years ago, Ma)1 has been linked to an order-of-magnitude decline in atmospheric CO2 levels and global climatic cooling by altering continental weathering processes, but observational constraints on atmospheric CO2 before the rise of forests carry large, often unbound, uncertainties. Here, we calibrate a mechanistic model for gas exchange in modern lycophytes and constrain atmospheric CO2 levels 410–380 Ma from related fossilized plants with bound uncertainties of approximately ±100 ppm (1 sd). We find that the atmosphere contained ~525–715 ppm CO2 before continents were afforested, and that Earth was partially glaciated according to a palaeoclimate model. A process-driven biogeochemical model (COPSE) shows the appearance of trees with deep roots did not dramatically enhance atmospheric CO2 removal. Rather, shallow-rooted vascular ecosystems could have simultaneously caused abrupt atmospheric oxygenation and climatic cooling long before the rise of forests, although earlier CO2 levels are still unknown. Dahl et al. present new evidence based on leaf gas-exchange in primitive vascular plants and fossil remains of some of their earliest ancestors. This alters our thinking on how plants impacted the Earth System and climate. [ABSTRACT FROM AUTHOR]

Brazilian law protects environments understood to be the remnants of historical ecologies. This article uses oral histories, silicate plant fossils, and stable isotopes to excavate one such protected fragment of Brazil's Atlantic Forest. Located on a former plantation in the Paraíba Valley of Rio de Janeiro, a region central to state and market formation, and to Atlantic slavery in the nineteenth century, this "forest" contains ecological histories different from those encoded in environmental law. Rather than a legislative failure, this incongruence constitutes an important structural feature of the juridical authority that marginalizes embodied ways of learning about the environment. This fundamental tension, related to who can know this place and by what means, has important implications for understanding the social meanings of environmental politics in the Atlantic world, which emerged in the context of the abolition of slavery. Environmental laws provided means of claiming knowledge and control over spaces of social reproduction created by freedpersons post abolition, underwriting enduring forms of land and labor management. [environmental legislation, land conflict, plantations, race, Brazil] [ABSTRACT FROM AUTHOR]

Pleuromeia Corda is an iconic lycopod genus in the Early Triassic floras of the world. Pleuromeia fossils are very significant in stratigraphy and palaeoenvironmental interpretation and have been regarded as an important Lower Triassic index fossil. Although some recent studies show that the genus occurred in the lower part of the Middle Triassic, no definite Pleuromeia has been reported from the late Middle Triassic and the younger strata so far. In this paper, some reproductive organ fossils of Pleuromeia from the upper Middle Triassic Tongchuan Formation in Shaanxi Province (belonging to the Ordos Basin), North China, are described for the first time, belonging to the new species Pleuromeia obovata Deng nov. sp. Highly accurate dating results of tuff layers indicate that the age of the new species is between 241.06 ± 0.12 Ma and 241.558 ± 0.093 Ma, equivalent to the early Ladinian. This is the youngest species of genus Pleuromeia so far. Spatiotemporal distribution of Pleuromeia indicates that the genus first appeared in the Induan (Early Triassic) in North China, occurred widespread and flourished in both Laurasia and Gondwana during the Olenekian (late Early Triassic), declined from the Anisian (early Middle Triassic), survived in the Ladinian in North China, and may have gone extinct as early as the end of the Middle Triassic. North China may well have included the place of origination and the last habitats of this genus. [ABSTRACT FROM AUTHOR]

3 Jul 1952) was fortunate in obtaining fossil wood that allowed him to determine the extant genus to which the Burmese fossils could be related: he recombined them in his previously published generic name, I Glutoxylon i K.A. Chowdhury (in Curr. He noted that several other problematic fossil wood types published under I Grewioxylon i awaited re-classification in different fossil wood genera, not even related to an extant " I Grewia i -like" fossil wood type. 1927) reviewed the fossil wood species referred to I Dipterocarpoxylon i by Kräusel (l.c. 1922, 1926) and assigned many of them to genera with quite different relationships. (2929-2931) Proposals to conserve the names Dipterocarpoxylon with a conserved type against Hippocrateoxylon, Dryobalanoxylon against Naucleoxylon, and Shoreoxylon against Bredaea and Grewioxylon (fossil Dipterocarpaceae, Magnoliophyta). [Extracted from the article]

Premise: The recognition of the Miocene Climate Optimum (MCO) in terrestrial palaeoenvironments of the Eastern Mediterranean is restricted to Lesbos and Lemnos Islands, Greece. This area is significant for its wood microfossils. A recentlydiscovered fossil wood assemblage from Gökçeada (Imbros) Island, Turkey, including tree species similar to the Greek findings, is thought to have an early Miocene age. Here, we revise the age of the latter plant fossiliferous locality, re-evaluate the area for the study of MCO for the terrestrial palaeoecosystems of the Eastern Mediterranean and the nomenclature errors referring to the occurrence of fossil wood. We present the plant-insect-environment interactions using detailed anatomical descriptions, of an extinct conifer and its extinct cambium miner feeding traces observed in its secondary xylem. Methods: Three thin sections were prepared with standard palaeoxylotomical techniques from a small section of the silicified wood; the sections were observed under a light microscope. The anatomy of the conifer and its damage patterns were compared with those of extant and fossil Cupressaceae and Agromyzidae, respectively. Pivotal results: The common anatomical features of the studied wood specimen and Hesperocyparis macrocarpa (Hartw.) Bartel and a shared characteristic (the number of the cross-field pits - a feature we consider of diagnostic value) with Xanthocyparis vietnamensis Farjon & T.H. Nguyên led to its assignment to the Hesperocyparis-Xanthocyparis-Callitropsis clade. The detailed study of the wound scars and anatomical abnormalities, the anatomical-environmental associations, and structural-functional reactions follow the identification of the wood's anatomy sensu Carlquist providing decisive results. Conclusions: Based on the distinctive characteristics presented, we identify our macrofossil as Cupressinoxylon matromnense Grambast, a stem or an extinct lineage of the Hesperocyparis-Xanthocyparis vietnamensis-Callitropsis nootkatensis clade with feeding traces of the fossil cambium miner of the genus Protophytobia Süss (Diptera: Agromyzidae), and anatomical damage and reaction tissue on adventitious shoots. The use of Protopinaceae and Pinoxylon F. H. Knowlton from the eastern Mediterranean are re-evaluated and corrections are provided. The age of the studied plant fossiliferous locality in Gökçeada is revised as middle Miocene, allowing the proposal of an eastern Mediterranean MCO hotspot, including Lesbos, Lemnos, and Gökçeada (Imbros) Islands. [ABSTRACT FROM AUTHOR]

Supercritical geothermal resources are in the preliminary exploration stage as a new type of clean energy and there are no practical utilization projects. The IDDP-2 well at Reykjanes geothermal field in Iceland encountered supercritical geothermal conditions in 2017, with a maximum temperature of 535 °C. The system is still in the field experiment stage and no exploitation work has been carried out. Hence, a hypothetical doublet geothermal system was simulated based on IDDP-2 to study the power generation potential and favorable operating conditions for future development of supercritical geothermal resources. A multiphase flow model is established to predict the fluid and heat flow characteristics. Furthermore, sensitivity and economic analyses were performed to evaluate the expected commercial and environmental benefits of the supercritical geothermal system. The results show that the system's evolution could be briefly divided into three stages according to the temperature variation. The power generation ranges between 5.4 MW~16.5 MW, and the levelized cost of electricity (LCOE) is 0.02 $/kWh. In addition, the system can reduce CO2 emissions, which are 1.2~7.75 Mt less than that of fossil fuel plants with the same installed capacity. The results prove the great development potential and commercial competitiveness of the supercritical geothermal system. [ABSTRACT FROM AUTHOR]

Some experiments and observations of free-living plants have found that increasing atmospheric concentration of CO 2 (p CO 2) is directly correlated with increasing discrimination against 13C during photosynthesis (Δ13C) in C3 plants. The inverted form of this correlation has been used to estimate p CO 2 in the geological past (i.e. the C3 plant proxy), but there has been little experimental work to establish the relative importance of p CO 2 as a driver of discrimination in more natural settings and over a range of p CO 2 relevant to the deep-time geologic record. Here we report on an experiment exploring the relationship between p CO 2 and Δ13C in Ginkgo biloba , a plant long used to infer past CO 2 levels because of the strong similarity of extant to fossil Ginkgo and the abundance of Ginkgo fossils with preserved cuticle from late Mesozoic and Cenozoic periods of warm global climate. We grew Ginkgo biloba plants for three years under ambient p CO 2 (∼425 ppm) and elevated levels (∼600, ∼800, and ∼ 1000 ppm) while measuring the carbon isotope composition of air (δ13C air) and leaves (δ13C leaf) as well as the ratio of internal to external CO 2 concentration (c i /c a), maximum photosynthetic assimilation rate (A max), C:N ratio, and leaf mass per area (LMA). We found no significant relationship between p CO 2 and Δ13C leaf or c i /c a. We did find a direct correlation of p CO 2 with A max , LMA, and C:N ratio. The lack of increase in Δ13C leaf with rising p CO 2 may result from the lack of change in c i /c a , thicker leaves that slow the rate of diffusion of CO 2 through the leaf to mesophyll cells, higher A max that drives more rapid consumption of intracellular CO 2 and/or changes in the relative proportions of starches, lipids or other compounds that have distinct isotopic compositions. Our results, along with a compilation of data from the literature on Δ13C leaf in many different types of C3 plants, suggest that Δ13C leaf does not consistently increase with increasing p CO 2. Rather, there is a diversity of responses, both positive and negative, that are not clearly related to taxonomic group or growth form but may reflect changes in leaf structure, stomatal response and A max under higher p CO 2. Given the complex relationship between Δ13C leaf and p CO 2 in living plants we consider Δ13C leaf of fossil plants to be an unreliable proxy for paleo-atmospheric p CO 2. [ABSTRACT FROM AUTHOR]

Seed germination is a crucial stage in the development of all plants. It normally occurs in the soil after the seed has fallen from the mother plant. In some infrequent instances, precocious germination (a type of viviparity or vivipary) occurs when the seed sprouts while still within the fruit. The present paper describes the first case of precocious germination of a fossil plant involving a number of seeds that have germinated in a pine cone embedded in Eocene Baltic amber. At the tips of the emerging hypocotyls are clusters of needles in fascicles of 5, associating the fossil with the extinct pine species Pinus cembrifolia Caspary described earlier from Baltic amber. Environmental implications of this discovery are discussed. [ABSTRACT FROM AUTHOR]

Studying exceptionally well-preserved biotas can bring significant answers to the rela)tionship between micro-organisms, biosignatures, and preservational processes. Among impressions of plants from Triassic and Jurassic beds of southernmost Brazil, there are branches and leaves coated by iron crusts, attributed to the precipitation of iron oxide-oxyhydroxides. Underneath the crusts, the leaves retained minute anatomical features of their epidermal cells and stomatal complexes, which are rare in other types of preservation. We evaluate the chemical nature and microstructure of these crusts to solve their genesis and the role of micro-organisms in the precipitation of iron minerals. For this purpose, we apply the following analytical geochemical techniques: Raman spectroscopy and Mössbauer spectrometry, X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). The crusts are composed of α-goethite and traces of smectite. We identified potential biogenic microstructures such as ferrihydrite nodules, bacterial exudates morphologically compatible to extracellular polymeric substances (EPS), and structures like twisted stalks and sheaths that fit the biogenicity criteria established so far. These microstructures suggest that the iron crusts were produced by the activity of fresh-water microaerophilic and neutrophilic organisms. The studied material allows us to reconstruct key diagenetic processes that facilitated authigenic preservation along with exceptionally well-preserved biosignatures. [ABSTRACT FROM AUTHOR]

In this contribution, fossil woods from the Valle de La Luna Member of the Upper Triassic Ischigualasto Formation at Ischigualasto Provincial Park, San Juan Province, Argentina, are described. The specimens are preserved as silica permineralization in tuffs intercalated with carbonaceous mudstone beds interpreted as distal floodplain facies. The fossil woods were assigned to the new species Agathoxylon argentinum since their anatomy differs from the known Mesozoic Gondwanan species of the genus Agathoxylon. The combination of characters present in the new taxon indicates an affiliation with the conifer family Araucariaceae. Signals of fungal-mediated wood decay were observed, comparable to the activity of basidiomycetes. Spherical structures attached to the walls of the tracheids were recognized and are interpreted as holocarpic chytrid fungi. The growth rings were quantitatively analyzed. Low values of percentage diminution, percentage latewood, and Ring Markedness Index, and a mean percentage skew of +11.5, were obtained, suggesting that the new species was an evergreen gymnosperm. The stratigraphic distribution and taxonomic composition of the Ischigualasto Formation fossil-plant-bearing levels were studied. A vegetation change is recorded in the fossil level bearing Agathoxylon argentinum n. sp., marked by the replacement of the corystosperm genera and a diminution of arboreal corystosperms. This floristic change, in addition to other evidence, indicates humid paleoclimatic conditions for the uppermost part of the Valle de La Luna Member of the Ischigualasto Formation. [ABSTRACT FROM AUTHOR]

Understanding long-term vegetation diversity patterns and their potential responses to climate and/or human driven processes are important for ecosystem modeling and conservation. Late-Holocene fossil pollen assemblage and associated vegetation diversity estimates provide an opportunity to explore the interactions among vegetation, climate, and human activities. A continuous 2000-year palynological record was obtained from the Beihai Wetland, southwestern China, to represent regional vegetation history, particularly the vegetation diversity changes. The results indicate that regional vegetation was dominated by deciduous broadleaved forest components (e.g. Alnus, deciduous Quercus), which showed a gradual decrease accompanied by expansion of herbaceous taxa (mainly Poaceae) after AD 800. Such progressive decline of forest was attributed to regional deforestation driven by intensified human activities, which was further confirmed by the increasing non-pollen polymorph abundance, particularly an abrupt rise after AD 1350. Vegetation diversity based on the Hill numbers (N 0, N 1, and N 2) showed a dramatic decline between ca. AD 200–400, which was triggered by regional fire events as shown by increased charcoal abundance from a nearby lake. The vegetation diversity reduced gradually after AD 800, especially the vegetation richness reflected by N 0, revealing the transitional process from climate-driven to human-dominated vegetation changes. Minor increases of vegetation diversity occurred during Chinese dynastical transitions, probably due to reduced human activities following war-induced population crises. On the multidecadal scale, variations in vegetation diversity correlated significantly with climate fluctuations (revealed by synthesized temperature of China and stable oxygen isotope record from Dongge Cave) before AD 800, indicating a climate dominant condition. Then, the correlation between vegetation diversity and climate declined after AD 800, representing a progressive transition to human-dominant condition. In addition, the compositional turnover based on DCCA of the fossil pollen assemblage revealed a stepwise decrease, indicating reduced vegetation turnovers under anthropogenic influences. [ABSTRACT FROM AUTHOR]

This contribution aims to interpret the producers and the paleoenvironmental context of Holocene rodent burrows (and associated ichnofossils) from the Late Pleistocene-Holocene Meaucó Formation, central La Pampa Province, Argentina. Fieldwork included a detailed sedimentary logging, a ground penetrating radar survey and documentation of the fossil burrow systems. The Meaucó Formation rest on erosive unconformity over the Upper Miocene-Lower Pliocene Cerro Azul Formation and display a vertical change from eolian dunes that become sparser up section (as imaged by ground penetrating radar) and were capped by a paleosol. The paleosol is covered by recent eolian dune and interdune deposits. The fossil rodent burrows occur up to 1.7 m below the paleosol and share several morphologic features with modern Ctenomyidae burrows, except the high slope of entrance and internal ramps, and the maximum depth of burrows. To explain these differences, it is proposed that the burrows were excavated by ctenomyids in ancient sloping surfaces of eolian dunes, which resulted in increased inclination and apparent maximum depth of the systems. This is an example of influence of environmental conditions on the architecture of rodent burrows, and can be of help when interpreting other similar fossil examples. The paleosol community associated with the fossil vertebrate burrows also included other organisms recorded by their trace fossils: horses (Hippipeda isp.), a scrubby vegetation (rhizoliths), coleoptera or spiders (Skolithos linearis), cicada nymphs (Feoichnus challa) and ants (Daimoniobarax isp.). • Extant Ctenomyidae burrow systems are subhorizontal. • Fossil Ctenomyidae burrows with high inclination related to eolian dunes. • Changes in burrow system architecture reflect environmental fluctuation. • Eolian dunes inferred from ground penetrating radar sections and grainsize analysis. • Diverse associated invertebrate and plant trace fossils. [ABSTRACT FROM AUTHOR]

Many permineralized conifer stems and trunks have been documented from the Jurassic strata of the Xinjiang Uygur Autonomous Region (Xinjiang), Northwest China. Xylem anatomical studies have showed that these stems and trunks belonged to a diverse range of plants. However, the leaf phenology and the paleoclimatic and paleoenvironmental significance of these fossil plants have rarely been studied. We quantitatively analyzed the anatomical characteristics of a permineralized conifer stem— Yiwupitys elegans Gou et Feng 2023—from the Middle Jurassic Xishanyao Formation in northeastern Xinjiang, which has distinct and wide growth rings in the secondary xylem. Analyses of the Mean Sensitivity and Ring Markedness Index of the growth rings suggest that a stable paleoclimate with regular seasonal fructifications likely prevailed during the Middle Jurassic in this area. The statistical analyses of cell diameters and anatomical features of leaf traces in six successive growth rings indicate that this fossil plant was deciduous. Our study elucidates the ecophysiological characteristics of a Middle Jurassic conifer plant and provides new insights into the corresponding paleoclimate and paleoenvironment based on quantitative cellular analysis of the fossil stem. • Growth rings and leaf trace have investigated for a Middle Jurassic conifer from China. • Quantitative analysis indicated the plant was deciduous. • Our results suggest warm–wet climate was prevailed during the Xishanyao Formation. [ABSTRACT FROM AUTHOR]

Well preserved Early-Middle Triassic plant fossils from Northwest Europe are relatively rare due to the environmental conditions within the Germanic basin during this time period. The only sphenophyte species commonly described in the floras that are found in the area, is Equisetites mougeotii. However, only stems without leaf sheaths were ever reported. Here, we describe sphenophyte stems with free standing leaves from the Upper Buntsandstein of Üdingen, Germany, which we attribute to the genus Neocalamites based on this characteristic and the difference, mainly in stem size, of the Üdingen material to E. mougeotii. Most of the material consists of internodal, infertile stems that are unbranched and vary in width. A few of these stems are three-dimensionally preserved. Due to the difference of the material to the other, rarely present, Neocalamites species reported from the Anisian of Western Europe, we propose the plant fossils from Üdingen to be a new species called Neocalamites vanderburghii n.sp. • Early-Middle Triassic (Anisian) horsetails with free standing leaves are described. • A few of these fossil stems are three-dimensionally preserved. • Before, only stems without leaf sheaths were ever reported in similar floras. • These were commonly attributed to Equisetites mougeotii. • Due to the free-standing leaves, we attribute our material to Neocalamites. [ABSTRACT FROM AUTHOR]

Plant fossils serve as critical proxies for interpreting past climates and environments, offering insights into the history of biosphere and climatic conditions. Here we describe a large tracheophyte cast, as well as the sedimentological settings in which it is preserved, expanding the paleobotanical database of the Itararé Group and contributing to the understanding of the LPIA in the Paraná Basin. This fossil occurs in Ponta Grossa, Paraná state, Brazil, within sedimentary levels interpreted as glacially dominated and deposited during the Late Paleozoic Ice Age (LPIA). The plant macrofossil is preserved as a cast, and the log is vertically oriented with a slight inclination in relation to the bedding plane. Taphonomic data indicate an allochthonous preservation, suggesting that the log was transported from inland areas to a plain before final burial. The identification of the tracheophyte cast within these glacial beds suggests that even in a dominantly glacial context, there were periods of episodic climatic amelioration. This finding implies that the climatic conditions during the Mississippian were not uniformly harsh, allowing the growth of vegetation as represented by the reported tracheophyta. • Record of a tracheophyte cast in allochthonous preservation in the basal Itararé Group. • The tracheophyte cast indicates episodic climatic amelioration, suggesting periods of frost-free conditions. • Dynamic climate changes and its impact on vegetation establishment in the Paraná Basin. [ABSTRACT FROM AUTHOR]

The integration of renewable energy sources into existing district heating systems is imperative for the decarbonization of the global energy system. This transition is particularly challenging in existing systems that were originally supplied by fossil fuel plants and designed to operate with high supply temperatures. Reducing supply temperatures to facilitate the integration of low exergy heat may not be suitable for the existing infrastructure, due to both the heating devices or the thermal substations that may not support significant reductions or to the distribution infrastructure that can be unable to handle the required mass flow rate increases. To address these challenges, this paper focuses on the distribution infrastructure by introducing a physical-based approach to explore the current potential for supply temperature reduction of existing district heating infrastructures, taking into account the hydraulics of the system. Indeed, being able to identify the possible hydraulic bottlenecks arising in the network is essential to enable the transition of the networks and requires an accurate modelling of the fluid dynamic of the system. The methodology is fast and versatile, making it suitable for applications from small-scale to large-scale systems. An application to a real large-scale network is presented, proving the wide applicability of the methodology. Promising results in terms of temperature reduction are shown to be possible: the analyzed infrastructure is currently capable of shifting its operation from 120 °C to about 102 °C without considering invasive structural interventions on the network, and further reductions up to 90 °C are conceivable by assuming some adjustments to the system configuration. [ABSTRACT FROM AUTHOR]

The fossil flora of the Matzitzi Formation, is a fluvial unit of late Paleozoic age exposed in southern Mexico, has been studied since the last century; however, the discovery of new plant elements during the last decade imposes a reevaluation of two aspects that have always been the subject of debate: the depositional age of the unit and the taxonomy of its paleoflora. The objective of the present work is to report new paleofloral records from two areas of the Matzitzi Formation as well as their chronological implications. The study sites are named Carretera and Coatepec. Nineteen genera and 11 species have been identified in beds from the Carretera site, whereas 23 genera and 16 species in beds from the Coatepec site. The analysis of floral assemblages of both sites shows that they share 49% of taxa. Ovopteris , Lesleya , Lobatopteris, and Trigonocarpus are unique to the Carretera site, while Coatepec is characterized by the presence of cf. Bjuvia, Schizoneura, and Velascophyllum. When analyzing the greatest ranges of the paleoflora awareness for the Carretera site indicates that deposition of these beds took place in a time interval that may span between Pennsylvanian and lower Permian. On the other side, the floral assemblage recovered from the Coatepec site indicates that the hosting beds were deposited in upper Permian time. U–Pb detrital zircon geochronology indicates that the maximum depositional age of the fossiliferous beds at the Carretera and Coatepec sites are of 276 ± 15 Ma and 254 ± 11 Ma, respectively. The integration of the paleontological and geochronological data obtained in this work suggests that the analyzed floral assemblage recovered from the Carretera site is of Kungurian age, whereas the one from the Coatepec site is of Lopingian age. Alternatively, we explore the possibility that deposits that are presently grouped within the Matzitzi Formation could be the vestiges of different fluvial cycles associated with different tectonic settings. Finally, the work on this unit has not finished, since there are still localities where its flora and age are still unknown. • Two age proposals are made for the Matzitzi Formation, Cisuralian and Lopingian • The Carretera locality presents a Cisuralian deposit age • The Coatepec locality presents a Lopingian deposit age • The Carretera locality presents unique taxa such as Lesleya and Lobatopteris • The Coatepec locality presents unique taxa such as Schizoneura and Velascophyllum [ABSTRACT FROM AUTHOR]

Dalbergia is a pantropical genus of Fabaceae with limited fossil records. In this study we describe diverse and well-preserved Dalbergia fossils distributed through Cenozoic (Eocene to Pliocene) strata in Yunnan Province, Southwest China. Comparison with newly collected modern samples from Eurasian forests and herbarium specimens allow accurate identification of our fossil materials, and we demonstrate that Yunnan Province represents an hitherto unrecognised hotspot for the diversification of Dalbergia. Our findings also include evidence of the earliest known mining damage reported on Dalbergia leaflets, which sheds light on their interactions with various arthropods (Leucoptera and other insects) during the early Neogene. As such, our results improve knowledge of Dalbergia fossils in East Asia and are crucial for understanding the evolutionary history of analogous mining behavior observed from modern Dalbergia. • The most complete Dalbergia fossil records from Southwest China hitherto ever reported. • Newly discovered fossils could significantly contribute to the understanding of Dalbergia diversification history in Asia. • Lyonetiidae mining on Dalbergia occurred in the early Miocene. • Biotas of Yunnan were closely related to the contemporary tropical regions since the Late Paleogene. [ABSTRACT FROM AUTHOR]

Vegetative leaves have long been considered a significant receiver of gaseous Hg in the atmosphere, offering the potential to passively monitor palaeo-atmospheric Hg concentrations; however, few constraints on this exist. In this study, we conduct Hg measurements on three Ginkgo leaf collections: i) modern leaves from ten sampling sites across China, ii) modern leaves collected monthly across one growing season in Nanjing (China), iii) fossil ginkgoaleans leaves from the Middle Jurassic (China). The results from this study reveal that the foliar Hg concentrations (with an average concentration of 61 ng·g−1, N = 272) were higher than those observed in Ginkgo leaf samples previously studied from Ireland and the USA. Additionally, the leaf age and atmospheric Hg concentrations represent two primary factors impacting foliar Hg contents in Ginkgo. Hg concentrations in fossil cuticular samples (with an average concentration of 585.5 ng·g−1) were observed notably higher than those in modern Ginkgo leaves (avg. 61 ng·g−1) and sediments from the same layers (avg. 113 ng·g−1). Considering possible Hg migration during fossilization, we suggested that the elevated Hg concentrations in fossil cuticles were attributed to both the retention of Hg in leaves and the loss of leaf content during fossilization. Based on 23 fossil ginkgoalean samples from 6 beds of the Dameigou section (spanning from the Early to the Middle Jurassic), Qaidam Basin, China, we detected a Hg anomaly through Hg concentrations in fossil cuticles during the presumed palaeo-volcanic event (the Karoo-Ferrar Large Igneous Province (LIP)). This preliminary test supports the notion that variations in Hg concentrations in fossil cuticle may potentially reflect the gaseous Hg changes in the Jurassic palaeo-atmosphere, triggered by LIP volcanism at this time. This finding highlights the possibility of using fossil plant cuticle as a Hg proxy of palaeo-atmospheric Hg loading. • Modern Ginkgo foliar Hg concentrations show significant correlations with leaf age and TGM background. • The palaeo-Hg0 was supported as one of the influential primary factors on Hg in fossil cuticles. • Hg anomaly in fossil ginkgoaleans was observed during the presumed paleo-volcanic event. • Hg variations in fossil cuticle potentially reflected paleo-atmospheric changes by volcanism. [ABSTRACT FROM AUTHOR]