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Cortland F Eble - One of the best experts on this subject based on the ideXlab platform.
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metalliferous coals of the westphalian a joggins formation cumberland basin nova scotia canada petrology geochemistry and palynology
International Journal of Coal Geology, 2000Co-Authors: James C Hower, Cortland F Eble, Andrew C Scott, John H Calder, David J Robertson, Lori J BlanchardAbstract:Abstract Five coals of Westphalian A (early Middle Pennsylvanian) age were sampled from the Joggins Formation section exposed along Chignecto Bay at Joggins, Nova Scotia. Coal beds along the bay were mined beginning in the early 17th century, yet there have been few detailed published investigation of the coal beds of this classic section. The lowermost coal, the Upper Coal 28 (Upper Fundy), is a high-vitrinite coal with a spore assemblage dominated by arboreous lycopsid spores with Tree Ferns subdominant. The upper portions of the coal bed have the highest ratio of well-preserved to poorly-preserved telinite of any of the coals investigated. Coal 19 (“clam coal”) has 88% total vitrinite but, unlike the Fundy coal bed, the telinite has a poor preservation ratio and half the total vitrinite population comprises gelocollinite and vitrodetrinite. The latter coal bed is directly overlain by a basin-wide limestone bed. The Lower Kimberly coal shows good preservation of vitrinite with relatively abundant telinite among the total vitrinite. The Middle Kimberly coal, which underlies the tetrapod-bearing lycopsid Trees found by Lyell and Dawson in 1852, exhibits an upward decrease in arboreous lycopod spores and an upward increase in the Tree fern spore Punctatisporites minutus . Telinite preservation increases upwards in the Middle Kimberly but overall is well below the preservation ratio of the Upper Fundy coal bed. The coals all have high sulfur contents, yielding up to 13.7% total sulfur for the lower lithotype of the Upper Fundy coal bed. The Kimberly coals are not only high in total and pyritic sulfur, but also have high concentrations of chalcophile elements. Zinc, ranging up to 15,000 ppm (ash basis), is present as sphalerite in fusain lumens. Arsenic and lead each exceed 6000 ppm (ash basis) in separate lithotypes of the Kimberly coals. Together these data are consistent with elevated pH in planar mires. The source of the elemental enrichment in this presumed continental section is enigmatic.
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the westphalian d fossil lepidodendrid forest at table head sydney basin nova scotia sedimentology paleoecology and floral response to changing edaphic conditions
International Journal of Coal Geology, 1996Co-Authors: Cortland F Eble, J H Calder, Martin R Gibling, Andrew C Scott, D J MacneilAbstract:Copyright (c) 1996 Elsevier Science B.V. All rights reserved. Strata of Westphalian D age on the western coast of the Sydney Basin expose a fossil forest of approximately 30 lepidodendrid Trees within one of several clastic splits of the Harbour Seam. A mutidisciplinary approach was employed to interpret the origins of the coal bed, the depositional history of the site and the response of the fossil forest to changing edaphic conditions. The megaspore and miospore records indicate that the mire vegetation was dominated by arboreous lycopsids, especially Paralycopodites, with subdominant Tree Ferns. Petrographic, palynological and geochemical evidence suggest that the Harbour coal bed at Table Head originated as a rheotrophic (cf. planarr mire (eutric histosolr. The mire forest is interpreted to have been engulfed by prograding distributary-channel sediments; sparse protist assemblages are suggestive of a freshwater delta-plain lake environment occasionally in contact with brackish waters. Lepidodendrids persisted as site colonizers of clastic substrates even after burial of the rheotrophic peatland and influenced the morphology of deposited sediment, but apparently were unable to colonize distributary channels. Equivocal taxonomic data (compression fossilsr show the fossil forest to have been composed of both monocarpic (Lepidodendronr and polycarpic (Diaphorodendron, Paralycopodites, ?Sigillariar lycopsids, genera recorded in the palynology of the uppermost ply of the underlying coal bed. Comparatively rare within the clastic beds of the fossil forest, however, is the stem compression of Paralycopodites, whose dispersed megapores and miospores dominate the underlying coal bed. Tree diameter data recorded equivalent to breast height indicate a forest of mixed age. These data would appear to suggest that some lepidodendrids employing a polycarpic reproductive strategy were better able to cross the ecological barrier imposed between peat and clastic substrates. Foliar compressions indicate that an understory or stand of Psaronius type Tree Ferns co-existed with the lepidodendrids on clastic substrates, which developed as incipient gleysol soils. The entombment of the forest can be ascribed to its distributary coastal setting, local subsidence and a seasonal climate that fostered wildfire and increased sedimentation.
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comparison of the petrography palynology and paleobotany of the little fire creek coal bed southwestern virginia u s a
Organic Geochemistry, 1995Co-Authors: Brenda S Pierce, Cortland F Eble, Ronald W StantonAbstract:Abstract Two continuous cores that penetrated the Lower Pennsylvanian Little Fire Creek coal bed in the Southwestern coal field in southwestern Virginia were sampled and X-ray radiographed to determine subunit distinctions. Comparison of petrographic, palynologic, and paleobotanic data from the same sample sets from the two cores allowed for comparison of compositional data within the Little Fire Creek coal bed. The proximate, petrographic, palynologic, and plant tissue data from two sets of samples indicate a high ash, gelocollinite- and liptinite-rich coal consisting of a relatively diverse paleoflora, including lycopsid Trees, small lycopsids, Tree Ferns, small Ferns, pteridosperms (seed Ferns), and rare calamites and cordaites. The relatively very high ash yields (3–80 wt%), the relatively thin subunits (1–28 cm), and the large scale vertical variations in palynomorph floras suggest that the study area was at the edge of the paleopea-forming environment. As a result, most of the compositional correspondences are among those components indicative of degradation or decomposition.
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comparison of the petrography palynology and paleobotany of the stockton coal bed west virginia and implications for paleoenvironmental interpretations
Organic Geochemistry, 1993Co-Authors: Brenda S Pierce, Ronald W Stanton, Cortland F EbleAbstract:Abstract The Stockton coal bed (Middle Pennsylvanian) is a relatively high ash coal composed primarily of moderately thin banded, sparsely thin banded, and nonbanded coal (splint and cannel coal). Comparisons of petrographic, palynologic, and paleobotanic data gathered from the same sample sets from a single column of the Stockton coal bed indicate that compositional correspondences among the sets exist regardless of coal type. Some correspondences are believed to exist because of original plant constituents and others because of the paleoenvironment of peat formation. Using some combination of these data is critical when interpreting paleoenvironmental conditions because (1) a direct correspondence is lacking between many of the data and (2) each of the three data sets provides a unique and important perspective on the paleomire. The Stockton paleomire in the area of this study supported a diverse flora that consisted of both small and arboreous lycopsids, small Ferns and Tree Ferns, calamites, cordaites, and pteridosperms. There appear to have been two successions of Lycospora spore-dominated, vitrinite-rich, liptinite-poor peat formation, which were followed by inertinite-rich peat formation marked by a Tree fern-dominant spore assemblage and abundant unidentifiable plant tissues. These are interpreted to be two water-laden or topogenous peat formational stages followed by slightly domed, better drained peat formation.
Robert Noll - One of the best experts on this subject based on the ideXlab platform.
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petrified marattiales pinnae from the lower permian of north western gondwana parnaiba basin brazil
Review of Palaeobotany and Palynology, 2014Co-Authors: Tatiane Marinho Vieira Tavares, Rosemarie Rohn, Ronny Roβler, Robert NollAbstract:Abstract This study concerns silicified fertile pecopterid pinnae from the Permian of the Parnaiba Basin, State of Tocantins, northern Brazil, attributed to a new fern taxon of Marattiales, Buritiranopteris costata gen. nov. et sp. nov. This fern bears groups of three or four sporangia radially arranged in closely spaced synangia, as in some species of Scolecopteris and Acitheca, but they are completely enclosed in thick and long down-curved foliar lobes. This morphology may represent a xeromorphic adaptation against long seasonal drought and direct solar irradiation. These pinnae obviously belonged to one of the abundant marattialean Tree Ferns, most probably Tietea, which were apparently successful as riparian vegetation of ephemeral rivers.
David B Lindenmayer - One of the best experts on this subject based on the ideXlab platform.
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salvage logging in the montane ash eucalypt forests of the central highlands of victoria and its potential impacts on biodiversity
Conservation Biology, 2006Co-Authors: David B Lindenmayer, K OughAbstract:Abstract: The two major forms of disturbance in the montane ash eucalypt forests of the Central Highlands of Victoria (southeastern Australia) are clearfell logging and unplanned wildfires. Since the 1930s wildfire has been followed by intensive and extensive salvage-logging operations, which may proceed for many years after a wildfire has occurred. Although applied widely, the potential effects of salvage logging on native flora and fauna have been poorly studied. Our data indicate that the abundance of large Trees with hollows is significantly reduced in forests subject to salvage harvesting. This has implications for the persistence of an array of such cavity-using vertebrates as the endangered arboreal marsupial, Leadbeater's possum (Gymnobelidues leadbeateri). Salvage logging also reduces the prevalence of multiaged montane ash forests—places that typically support the highest diversity of arboreal marsupials and forest birds. Limited research has been conducted on the effects of salvage logging on plants; thus, we constructed hypotheses about potential impacts for further testing based on known responses to clearfell logging and key life history attributes. We predict many species, such as vegetatively resprouting Tree Ferns, will decline, as they do after clearfelling. We also suggest that seed regenerators, which typically regenerate well after fire or conventional clearfelling, will decline after salvage logging because the stimulation for germination (fire) takes place prior to mechanical disturbance (logging). Understory plant communities in salvage-logged areas will be dominated by a smaller suite of species, and those that are wind dispersed, have viable soil-stored seed remaining after salvage logging, or have deep rhizomes are likely to be advantaged. We recommend the following improvements to salvage-logging policies that may better incorporate conservation needs in Victorian montane ash forests: (1) exemption of salvage logging from some areas (e.g., old-growth stands and places subject to only partial stand damage); (2) increased retention of biological legacies on burned areas through variations in the intensity of salvage logging; and (3) reduction in the levels of physical disturbance on salvage-logged areas, especially through limited seedbed preparation and mechanical disturbance.
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structural features of old growth australian montane ash forests
Forest Ecology and Management, 2000Co-Authors: David B Lindenmayer, Ross B Cunningham, C F Donnelly, Jerry F FranklinAbstract:Abstract We examined structural features of montane ash stands that varied from 15 to 300+ years of age in the Central Highlands of Victoria, south-eastern Australia. Extensive field data were gathered for our investigation and were drawn from >3700 survey plots on >625 sites located throughout the study region. Much of our study focussed on understorey features because extensive past studies in these forests have highlighted their importance as key habitat components for wildlife. A wide range of stand features, including the abundance of shrubs, the prevalence of Tree Ferns, the presence of Acacia spp., the presence of Myrtle Beech (Nothofagus cunninghamii), and the number of vegetation strata (a measure of vertical heterogeneity) varied considerably between age classes; most attributes were significantly (p The traditional view of disturbance in montane ash forests is that of high-intensity stand-replacing wildfires which produce even-aged regrowth forests. However, our data suggest that low-intensity, non-stand-replacing fires or only partial stand-replacing fires, have occurred in many old-growth montane ash stands, both to create multi-aged stands and to re-juvenate components of the understorey — a process leading to asynchrony in the ages of understorey and some elements of the overstorey. Thus, the structural variability, and the patterns of natural disturbance leading to such conditions, appears to be more complex than often previously recognised. This has important implications for both nature conservation strategies and timber harvesting practices in montane ash forests. Existing high-intensity clearfell logging operations produce an even-aged dominant overstorey as well as understorey and overstorey plants of the same age. If logging effects are to more closely resemble natural disturbance regimes and promote structural complexity in stands of harvested forest to enhance wildlife habitat values, then a wider range of types of harvesting methods (in addition to clearfelling) need to be employed.
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the conservation of arboreal marsupials in the montane ash forests of the central highlands of victoria south eastern australia v patterns of use and the microhabitat requirements of the mountain brushtail possum trichosurus caninus ogilby in retained linear habitats wildlife corridors
Biological Conservation, 1994Co-Authors: David B Lindenmayer, Ross B Cunningham, C F Donnelly, B J Triggs, M BelvedereAbstract:Abstract Hairtubing, a technique for detecting mammals, was used to census arboreal marsupials at 70 sites in the timber production montane ash forests of the central highlands of Victoria, south-eastern Australia. Of these sites, 41 were located in linear strips or wildlife corridors and the remaining 29 were in stands of contiguous montane ash forest. Four species of arboreal marsupials were detected in the hairtubing surveys but only one, the mountain brushtail possum Trichosurus caninus Ogilby, was recorded in sufficient numbers to allow subsequent analysis. Data derived for T. caninus from hairtubing studies were compared with those from earlier surveys where stagwatching was used to determine the presence and abundance of the species in retained linear strips. T. caninus was found to be absent from many retained strips during stagwatching surveys but was subsequently detected by hairtubing. Movement by animals into retained linear strips from surrounding areas of contiguous forest, probably whilst foraging, was the most logical explanation for this result. Statistical analyses revealed that T. caninus was most likely to move into strips that supported few Trees with hollows and thus areas of poor habitat suitability where there were few resident animals. Such forays may represent an adoption of a retained area as part of an animal's home range. These findings suggest possible functional differences in the use of retained linear strips by T. caninus where some sites provide habitat for resident animals and others, of poorer habitat quality, are used by individuals that do not live in the strip. Within the survey sites, T. caninus was most likely to be detected by hairtubing in those plots where there were numerous Tree Ferns, Dicksonia antarctica and Cyathea australis , and where the Trees Acacia dealbata and A. melanoxylon were present. Thus, some microhabitat features may influence the patterns of use by T. caninus within areas of retained forest. The implications of our results for wildlife conservation in timber production montane ash forests are discussed.
Ting Wang - One of the best experts on this subject based on the ideXlab platform.
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complete chloroplast genome sequence of a Tree fern alsophila spinulosa insights into evolutionary changes in fern chloroplast genomes
BMC Evolutionary Biology, 2009Co-Authors: Xuan Yi, Yingjuan Su, Yongxia Yang, Ting WangAbstract:Background Ferns have generally been neglected in studies of chloroplast genomics. Before this study, only one polypod and two basal Ferns had their complete chloroplast (cp) genome reported. Tree Ferns represent an ancient fern lineage that first occurred in the Late Triassic. In recent phylogenetic analyses, Tree Ferns were shown to be the sister group of polypods, the most diverse group of living Ferns. Availability of cp genome sequence from a Tree fern will facilitate interpretation of the evolutionary changes of fern cp genomes. Here we have sequenced the complete cp genome of a scaly Tree fern Alsophila spinulosa (Cyatheaceae).
Tatiane Marinho Vieira Tavares - One of the best experts on this subject based on the ideXlab platform.
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petrified marattiales pinnae from the lower permian of north western gondwana parnaiba basin brazil
Review of Palaeobotany and Palynology, 2014Co-Authors: Tatiane Marinho Vieira Tavares, Rosemarie Rohn, Ronny Roβler, Robert NollAbstract:Abstract This study concerns silicified fertile pecopterid pinnae from the Permian of the Parnaiba Basin, State of Tocantins, northern Brazil, attributed to a new fern taxon of Marattiales, Buritiranopteris costata gen. nov. et sp. nov. This fern bears groups of three or four sporangia radially arranged in closely spaced synangia, as in some species of Scolecopteris and Acitheca, but they are completely enclosed in thick and long down-curved foliar lobes. This morphology may represent a xeromorphic adaptation against long seasonal drought and direct solar irradiation. These pinnae obviously belonged to one of the abundant marattialean Tree Ferns, most probably Tietea, which were apparently successful as riparian vegetation of ephemeral rivers.
