Critical review of research on the Lower Jurassic flora of Poland

The Lower Jurassic plant macrofossils of Poland are poorly known. Relatively rich sources of fossils are found in only a few outcrops in the Holy Cross Mountains. Other described plant remains come from drill cores taken from most areas of Poland, but as a rule these are single specimens. The only professional descriptions of Lower Jurassic macroflora are papers by Raciborski, Makarewiczówna, and a team of researchers consisting of Reymanówna, Barbacka, Ziaja, and Wcisło-Luraniec. Raciborski’s fossil collection is still available for research and revision. Such work is in progress. The collection described by Makarewiczówna contained many interesting specimens but unfortunately the majority of them are now missing. Stratigraphic research by geologists has provided some new specimens from drill cores and outcrops in the Holy Cross Mountains but these have not been subjected to detailed palaeobotanical analysis. The palynology of the Lower Jurassic was focused on biostratigraphy from the outset of that research. As an outcome it provided spore-pollen and megaspore zonations for Lower Jurassic strata in Poland. The Polish Lower Jurassic flora is comprised of ferns (very numerous), lycopsids, sphenopsids, cycadaleans, bennettitaleans, gnetaleans, ginkgoaleans, and conifers. This flora is taxonomically poorer than the equally old and geographically close floras of Denmark, Sweden, and Germany. Macrofloristic data have been used by geologists as an important source of information for assessing the age of Lower Jurassic formations, particularly in the Holy Cross Mountains. Hence the need for the old collections to be taxonomically revised and for new material from outcrops and drill cores to be examined and described

Plant remains from the Polish Triassic : present knowledge and future prospects

The Triassic plant macrofossils of Poland are very poorly known. There are few Triassic rock exposures here, they contain very few plant specimens, there is little scientific interest in the subject, and the rare plant remains found in drill cores are of low stratigraphical significance. The Lower Triassic macroflora is surprisingly poorer taxonomically than coeval European floras, and only single specimens have been found. The flora of the Middle Triassic is even poorer as a result of the Muschelkalk sea transgression. Only the Upper Triassic floras contain many specimens and taxa. The Upper Triassic macrofloras from Polish territory are well known since the early 19th century. Pioneering descriptions of these floras were given by Goeppert and Raciborski. From the Polish Triassic, the seed fern Lepidopteris ottonis (index species for the Rhaetian stage) and Neocalamites lehmannianus (sphenopsid species typical of almost all European Upper Triassic and Lower Jurassic floras) were described for the first time ever. In the 20th century only single specimens were described from outcrops and drill cores. Barbacka revised Lepidopteris ottonis specimens from old collections and described some new material. Palynological research on Triassic strata in Poland intensified from the 1970s on. That work has produced spore-pollen and megaspore zonations for Triassic strata in Poland, but the correlation of the dispersed spores and pollen grains with their parent plants is low. The Polish Triassic flora is comprised of ferns, lycopsids, sphenopsids, cycads, bennettitaleans, ginkgoaleans and conifers. This flora is taxonomically poorer than equally old and geographically close European floras. All available data about Polish Triassic plants fossils are critically summarised in this paper for the first time. The biostratigraphical and lithostratigraphical correlations of Polish Triassic floras with other European Triassic floras are outlined. New macrofloral assemblages for the Lower and Middle Triassic and macrofloral assemblage zones for the Upper Triassic are proposed for Poland. Recent new finds of taxonomically rich, abundant and well-preserved floras accompanying vertebrate remains in Silesia provide an opportunity for comprehensive research on Polish Triassic floras. This should improve our perception of their taxonomy and allow them to be described in evolutionary and palaeoecological contexts

Critical review of studies of Carboniferous and Lower Permian plant reproductive organs in Poland with complete list of so far published taxa

Reproductive organs of Carboniferous and Lower Permian plants are poorly known in Poland. There are very few monographs on this topic and in them older determinations often require revision. In addition many specimens, including some nomenclaturatal types, have been lost or damaged. The end of the 19th and early 20th century was a period of intense activity in Silesia by eminent geologists and palaeobotanists from Germany, in particular Goeppert, Štúr, Roemer, Potonié and Gothan. However, many papers from this period are now diffi cult to access, even though some have gained high reputation and are highly cited in the literature. The materials collected in this period are gathered in many German museums and are still used for the taxonomic revisions and descriptions of new taxa. In the 1930s, two papers written by Bocheński on lycopod cones remain to this day highly cited in the literature. The innovative research techniques used by Bocheński and the excellent photographic documentation of specimens provided placed them among the classic articles on the topic. Studies of Carboniferous flora in the period after World War II were mainly aimed at biostratigraphy. The published papers are generally reviews of the flora of separate horizons or boreholes. Reproductive organs were typically determined only up to the level of genus, and the articles lacked accurate descriptions and rarely were they documented with photographs of specimens. In this paper all published records of Polish Carboniferous and Lower Permian plant reproductive organs are collated and critically reviewed. At least 13 genera and 30 species of lycopsid cones and sporophylls, 10 genera and 50 species of sphenopsid cones, 18 genera and 37 species of pteropsid fertile pinna, 1 genus and species of noeggerathialean cone, 30 genera and 65 species of pteridosperm ovules and pollen organs, 3 genera and 4 species of cycadalean seeds and macrosporophylls, 7 genera and 30 species of cordaitalean strobili and seeds, 3 genera and species of conifer reproductive organs have been recorded so far. Only about half of these accounts have been adequately documented with good illustrations. It is apparent from this summary, that it is necessary to review and, as far as possible, fully describe Carboniferous and Lower Permian plant reproductive organs from Poland to determine an accurate record of their composition and diversity

Sphenopsid and fern remains from the upper triassic of Krasiejów (SW Poland)

Hydrophilic elements, such as sphenopsids and fems, are rare in the flora of the Krasiejów site and they are poorly preserved. One sphenopsid species, Neocalamites merianii, was recognised. It is preserved as impressions, flattened casts, moulds and isolated leaves. So far, only one small fern specimen, determined as Sphenopteris sp., has been found. These elements probably were transported to the site of deposition and did not grow where they were buried

Putting community in Community Schools: Organizational and Cultural Contention in a Public-Private Partnership

Public-private partnerships as a new organizational form for delivering health and human services to those who require them remains an under-studied but important topic of research in an era significantly influenced by the weakening of the traditional civic welfare infrastructure. Based on two years of ethnographic research including in-depth interviews and participant observation, this research aimed to understand better how the concept of community held by members of the public-private partnership influenced their collective attempts to create a full-service community school program in the Brighton Park neighborhood of Chicago. Research revealed that members of the partnership negotiated and contested the idea of community which then had direct effects on their expectations and implementation efforts in the neighborhood. A small group, representing different organizations and leadership levels within the larger partnership held a similar idea of community which united them in their shared strategies to respond to traditional organizational authority structures. Research also revealed that neighborhood voices and those of school officials played little role in the partnership\u27s efforts to imagine and implement the community school model, suggesting that public-private partnerships like these might be more likely working on behalf of the neighborhood as opposed to with the neighborhood in efforts to create community-level change

Multicast traffic aggregation in MPLS-based VPN networks

This article gives an overview of the current practical approaches under study for a scalable implementation of multicast in layer 2 and 3 VPNs over an IP-MPLS multiservice network. These proposals are based on a well-known technique: the aggregation of traffic into shared trees to manage the forwarding state vs. bandwidth saving trade-off. This sort of traffic engineering mechanism requires methods to estimate the resources needed to set up a multicast shared tree for a set of VPNs. The methodology proposed in this article consists of studying the effect of aggregation obtained by random shared tree allocation on a reference model of a representative network scenario.Publicad

Carboniferous plants preserved within sideritic nodules : a remarkable state of preservation providing a wealth of information

Fossil plants preserved within sidertitic nodules have been known from Europaean and North American Carboniferous coal measures since the early 19th Century. However, only a few of them have been described thoroughly palaeobotanically, mainly in the 19th and early 20th centuries; thus their taxonomy often requires revision. Animal fossils preserved within sidertitic nodules beside plant fossils became a base of the description of many rare new taxa of animals undiscovered in other modes of preservation. Published hitherto works about such preserved fl ora indicate that plants preserved within concretions represent rare taxa, not known in other modes of preservation. The dissimilarities in composition of fl oras preserved in ironstone concretions when compared to those from surrounding sediments likely results from the process of concretion formation which selectively infl uences the preservation of small, delicate plant organs. The most famous fl oras preserved within concretions come from Mazon Creek in the USA and Coseley in Great Britain. These localities were the source of many previously unknown taxa with important evolutionary signifi cance. The new flora preserved within concretions has been discovered recently in Poland in Sosnowiec (Upper Silesia). It contains new, hitherto unknown taxa particularly plant reproductive organs. Comparison of the taxonomy and taphonomy of the ironstone concretion flora from Sosnowiec with other similar assemblages from the Carboniferous of Europe and North America has reveals many similarities steming from a common mode of preservation. Due to the exceptional three-dimensional preservation of the plant fossils, in particular reproductive organs key to the understanding of evolutionary relationships, the locality at Sosnowiec can be regarded as an important new Lagerstätte, and the first such site recognized in Poland. The use of pioneering techniques in high-resolution X-ray microtomography promises to yield yet further information on the biota of this new locality

Fossil flora of Middle Jurassic Grojec clays (southern Poland). Raciborski’s original material reinvestigated and supplemented. I. Sphenophytes

Sphenopsid remains from Grojec clays (Grojec, Poręba, Mirów) collected and described by Raciborski in 1894 are re-examined for the first time and supplemented by Raciborski’s unpublished material housed at the Jagiellonian University (Institute of Botany) and by Stur’s preliminarily described material stored at the Geological Survey of Austria. Three species of Equisetum created by Raciborski (Equisetum renaulti, E. remotum, E. blandum) are now attributed to the common Jurassic species Equisetites lateralis, and the earlierundescribed Equisetites cf. columnaris is recognised. The occurrence of Neocalamites lehmannianus (originally described by Raciborski as Schizoneura hoerensis) has been confirmed from Grojec. The material that Raciborski referred to this species seems to be heterogeneous, and some specimens are now removed to the new proposed species Neocalamites grojecensis Jarzynka et Pacyna sp. nov. The new species is diagnosed by the following features: only a few prominent ribs present on shoot, leaf scars relatively large and ellipsoidal, numerous free leaves, vascular bundles alternate at node. Possibly the new species derives from Neocalamites lehmannianus or at least is closely related to it. Part of the poorly preserved remains can be determined only as Neocalamites sp. Another species created by Raciborski, Phyllotheca (?) leptoderma, is based on poorly preserved type specimens. Some of the unpublished specimens stored at the Jagiellonian University (Institute of Botany) correspond to Raciborski’s description, but considering the poor preservation of the original material and the not very realistic published illustrations of this species, they rather should be regarded as indeterminate cortical fragments of Neocalamites lehmannianus and/or badly preserved external cortical surfaces of the new species Neocalamites grojecensis. Phyllotheca (?) leptoderma should be considered a nomen dubium

Bulk and local properties of intermetallic GdAgSn compound

The results of magnetic susceptibility as well as electric resistivity measurements complemented with ^{155}Gd Mössbauer spectroscopy investigations carried out within wide temperature range for GdAgSn compound are discussed