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In Luxemburg sind infolge von Landnutzungsintensivierungen nur noch wenige Relikte nährstoffarmer Feuchthabitate mit hohem Naturschutzwert erhalten. Eine kleinräumig differenzierte Untersuchung der Zusammenhänge zwischen Bodenfaktoren und Vegetation stand für diese Relikte bisher aus. Aus diesem Grund wurden in fünf Luxemburger Niedermoorkomplexen Vegetationszusammensetzung, Vegetationsstruktur (90 %-Perzentil der Vegetationshöhe, Streudeckung) und für die Pflanzenernährung relevante, bodenchemische Variablen (pH-Wert, Phosphor-, Kalium-, Calcium-, Magnesium-Gehalt) erfasst sowie Ellenberg-Zeigerwerte (Feuchte- und Nährstoff-Zahl) ausgewertet. Dabei ging es insbesondere um die Klärung der Fragen, welche Umweltgradienten der auffälligen Zonierung in Kern- und Randbereiche zugrunde liegen und welche Habitateigenschaften mit der Anzahl von gefährdeten Arten korrelieren. Hierzu wurden insgesamt 74 Kleinflächen in den beiden Zonen angelegt und floristisch sowie bodenchemisch analysiert.
Die Kleinflächen spannten einen Säuregradienten von annähernd drei pH-Stufen über die Gebiete hinweg auf (pH 3,9–6,5). Es ließen sich floristische, strukturelle und bodenchemische Unterschiede zwischen den Zonen ausmachen. In den meisten Gebieten unterschieden sich Diversität (in Kernbereichen erhöht) und Produktivität (nach Maßgabe von 90 %-Perzentil und Nährstoff-Zahl in Randbereichen erhöht). Die bodenchemischen Variablen zeigten je nur in einzelnen Gebieten Zonenunterschiede. Die beiden Gebiete mit den niedrigsten bzw. höchsten pH-Werten wiesen die meisten Variablen mit signifikanten Zonenunterschieden auf. Die Feuchte-Zahl war in keinem Gebiet zonenkennzeichnend. Die Diversität an bedrohten Arten korrelierte am häufigsten mit dem Magnesiumgehalt im Boden (meist positiv) und dem 90 %-Perzentil (stets negativ).
Unsere Ergebnisse legen nahe, dass in den untersuchten Niedermoorkomplexen mehrere Variablen zugleich und in unterschiedlicher Kombination für die Zonation verantwortlich sein könnten. Es werden Managementoptionen für die gefährdeten Gebiete diskutiert.
Central European dry grasslands are remarkably diverse plant communities that occur at the western edge of the Eurasian forest-steppe zone and harbour many species of continental distribution. Although their plant community types have been described in detail, the diversity patterns and their environmental determinants are still poorly known for these grasslands. Here, we study environmental drivers of species composition and richness in dry grasslands of northern Bohemia (České středohoří Mts) and central Bohemia (Křivoklát region), both in the Czech Republic. In vegetation plots of 100 m2 we recorded all vascular plant species, measured soil chemistry variables, above-ground biomass production and nutrient concentrations in biomass. Species richness in these plots ranged from 13 to 55. The relationships between species composition and the environment were explored using detrended correspondence analysis and canonical correspondence analysis, while the relationships between species richness and the environment were assessed using univariate and multiple regression models. In both regions, species composition and richness strongly responded to the soil pH (ranging from 4.0 to 7.8), which was positively correlated with calcium and magnesium concentrations and negatively with annual precipitation. The response of species richness to soil pH was unimodal with a peak at pH of about 6.5 in the České středohoří Mts, and positive in the Křivoklát region. Plots on soils with a pH higher than 5 consistently contained more than 35 species. In the České středohoří Mts, species richness was positively related to the aboveground biomass production, whereas in the Křivoklát region, this relationship was only significant for graminoid species. In both areas, plots with soils deeper than 20 cm and with aboveground biomass dry weight above 200 g/m2 harboured more than 40 species per 100 m2. Moreover, in the České středohoří Mts, nitrogen concentrations in the biomass had considerable effects on both species composition and richness: species numbers were lower at sites with higher nitrogen concentration. This indicates a threat to diversity of these dry grasslands under currently high atmospheric nitrogen deposition coupled with the absence of management at most of the studied sites.
Cryophytic steppes in the Minusinskaya intermountain basin containing plant species that are predominantly distributed in the alpine zone such as Androsace dasyphylla, Dryas oxyodonta, Festuca sphagnicola, Kobresia myosuroides, K. filifolia, Minuartia verna, Oxytropis bracteata, Sagina saginoides, Papaver nudicaule, Patrinia sibirica, Pedicularis lasiostachys, Pulsatilla ambigua, Saussurea schanginiana, which are considered remnants of the Pleistocene vegetation. Based on 89 relevés, we classified cryophytic steppes using the Braun-Blanquet method within two phytosociological classes: Central Asian steppes of the Cleistogenetea squarrosae and West Palearctic steppes of the Festuco-Brometea. Three associations (Androsaco dasyphyllae-Caricetum pediformis, Pulsatillo patentis-Caricetum pediformis and Bupleuro multinervi-Helictotrichetum desertori) with three subassociations and three variants were described with respect to their phytosociological affinities and ecology. DCA ordination showed floristic differences between syntaxa, while correlations of DCA axes and floristic and environmental variables detected substrate type and temperature regime as presumably main drivers for vegetation differentiation. Another driver for vegetation differentiation seems to be continentality of the climate. Small scale distribution of cryophytic steppes were mapped using satellite images with resolution of 1.8 m. Cryophytic steppes always occupy only small areas in landscapes, on convex parts of undulated microrelief of mountain slopes and summits characterised by drought in summer and deep soil freezing in winter. These special micro-ecological conditions play an essential role for the existence of alpine flora in the Minusinskaya intermountain basin.
Bei der Lorbeerkirsche handelt es sich um eine giftige Pflanze, deren toxische Wirkung durchaus nicht zu unterschätzen ist. Das Pflanzenporträt der Lorbeerkirsche dazu beitragen, die Art richtig ansprechen zu können, um mögliche Vergiftungen zu vermeiden. Darüber hinaus wird im Folgenden darüber informiert, welche positive Wirkung das beliebte Hecken- und Sichtschutzgehölz hat, wo die Art ursprünglich wächst und dass sie mittlerweile in milden Gebieten in Deutschland auch außerhalb der Gärten und Parks wild wachsend angetroffen werden kann.
Bei der Exkursion zum Westhafen des Rhein-Herne-Kanals standen vor allem frühblühende Arten der Stadtflora auf dem Programm. Auf dem Cranger Kirmesplatz mit seinen mageren Rohbodenflächen aus Asphalt, Beton und Bauschutt wächst eine typische Pioniervegetation. Weiter ging es über die beeindruckende Schleuse auf die gegenüberliegende Seite des Rhein-Herne-Kanals, an dessen Wegrändern und Ufern weiter erklärt, bestimmt und rege diskutiert wurde.
Ohne Drittmittel für seine Forschung kommt kaum noch ein Wissenschaftler aus. Immer mehr kostbarer Zeit verbringen Forscher damit, endlose Anträge auszufüllen. Antragsprosa ist längst eine Wissenschaft für sich. Der Jurist Rainer Maria Kiesow hat seine Form des "exzellenten Anschreibens" gefunden – eine Glosse mit spitzer Feder geschrieben.
Exkursion: Bochum-Weitmar, städtischer Friedhof und Schlosspark, Koniferen und andere Immergrüne
(2014)
Der Städtische Friedhof in Bochum-Weitmar weist eine hohe Vielfalt an Koniferen und anderen immergrünen Arten auf. Neben den gängigen und in der Region typischen Friedhofsgehölzen wachsen hier außerdem einige, nicht so häufig gepflanzte Arten, wie z. B. die Schirmtanne (Sciadopitys verticillata). Auch im angrenzenden Weitmarer Schlosspark sind trotz gravierender Umgestaltungen in den letzten Jahren noch immer einige seltenere Koniferen-Arten vorhanden, wie z. B. die Sicheltanne (Cryptomeria japonica) und die Weihrauchzeder (Calocedrus decurrens).
"Ach!" würde Goethe vermutlich ausrufen, sähe er die Kleinteiligkeit der heutigen Forschung – und auch sein Faust verzweifelt am gestaltlosen "Wissensqualm". Goethe wehrt sich vehement gegen eine Zersplitterung der Wissenschaft in unzählige Einzelphänomene. Er schätzt die Universalisten, "die das Allgemeine im Auge haben und gern das Besondere an- und einfügen möchten".
Desertification is a major problem in Sudano-sahelian West Africa, including the loss of biodiversity and vegetation cover. The loss of related ecosystem services is having a severe impact on human wellbeing. To facilitate assessments of these aspects of desertification, we decided to find plant species suitable as indicators. Based on a large database of vegetation plot data for Burkina Faso, we identified species associated with high or low levels of species richness and vegetation cover by calculating average values of these measures from vegetation plots on which they occur. To account for the differences between the dry Sahel and the more humid Sudan, we separated the plots of our study area in three vegetation zones (Sahel, North Sudan, South Sudan). Furthermore, herbs and woody plants were analysed separately, as they were usually represented in different plot sizes in the primary data. For each combination of species richness or vegetation cover, vegetation zone and growth form we identified ten species indicating low and another ten species indicating high values and assigned indicator values based on the average values of these species in the relevés.
The African species Cheiracanthium furculatum Karsch, 1879 was recognised as being introduced to Germany and is re-described and illustrated in the present study. C. tenuipes Roewer, 1961 is recognised as a junior synonym of C. africanum Lessert, 1921 (new synonymy); both subspecies of C. strasseni Strand, 1915, namely C. strasseni strasseni Strand, 1915 and C. strasseni aharonii Strand, 1915, are recognised as junior synonyms of C. mildei L. Koch, 1864 (new synonymies). Photographic images of the copulatory organs of the types of C. cretense Roewer, 1928, recently synonymised with C. mildei, are provided and discussed in the course of intraspecific variation in C. mildei. The female holotype of C. rehobothense Strand, 1915 is re-described and illustrated. Relations of C. rehobothense to other Cheiracanthium species are discussed.
An annotated catalogue of the rare mesothele spiders (Araneae: Mesothelae: Liphistiidae) held in the Museum für Naturkunde Berlin is presented. The museum hosts non-type specimens of nine species representing all three currently recognised genera, namely: Liphistius desultor Schiödte, 1849, L. malayanus cameroni Haupt, 1983, L. cf. thaleban Schwendinger, 1990, Heptathela kikuyai Ono, 1998, H. kimurai (Kishida, 1920), H. yanbaruensis Haupt, 1983, Ryuthela ishigakiensis Haupt, 1983, R. nishihirai (Haupt, 1979) and R. tanikawai Ono, 1997 (spec. reval.). The geographical focus of this collection is Malaysia and Japan, and most of the material was collected by the Berlin-based zoologist Joachim Haupt.
Die europäische Spinne des Jahres 2014, Linyphia triangularis (Clerck, 1757), wird vorgestellt. Erstmals ist es eine Linyphiide, eine Baldachinspinne. Ihre Merkmale und Eigenschaften (z.B. Ökologie, Lebensraum, Netz, Phänologie) werden kurz beschrieben. Der Wahlmodus, die beteiligten Länder und zahlreiche Links zu den unterstützenden Gesellschaften und Verbreitungskarten werden genannt.
Silometopus ambiguus (O. Pickard-Cambridge, 1905) is a species occurring in coastal habitats from northeastern to western Europe. S. curtus (Simon, 1881), occurring in southern France and north-eastern Spain, was for a long time mixed up with S. ambiguus, even though corrections have been published very early and several times. This contribution summarizes publications on this topic, discusses doubtful records of both species and proposes corrections for the World Spider Catalog; and thus tries to avoid repetitions of the mistake in the future.
Schreibt man etwas über einen bedeutenden Forscher, so stehen im allgemeinen seine wissenschaftlichen Verdienste im Mittelpunkt; lange Publikationslisten, besondere Beiträge, die zu einem bedeutenden Fortschritt im entsprechenden Wissensgebiet geführt haben, werden „abgearbeitet“. Wer den wissenschaftlichen Verdienst von Joachim Haupt (* 13. Januar 1942, † 30. April 2013) bemessen will, der schaue nur in so bedeutende Bücher wie „den Foelix“ (Biologie der Spinnen), die „Neurobiology of arachnids“ oder die „Ecophysiology of spiders“ (Foelix 1992, Barth 1985, Nentwig 1987) – in allen ist Joachim Haupt zitiert, im Überblickswerk über unsere – und seine! – Lieblingstiere ebenso wie in den Spezialwerken.
Wet meadows are transitional habitats between wetlands and dry-mesophilous grasslands; thus, they are vital in sustaining biodiversity as sources, stepping stones and green corridors of species dispersal. It is especially valid for inland alkali vegetation, where high landscapescale patchiness is typical and rapid shifts between vegetation types occur frequently. Solonetz meadows (Beckmannion eruciformis) are among the bestpreserved open habitats in Europe harbouring a unique flora including several endemics. Besides their importance, studies on the vegetation of solonetz meadows are scarce even though this knowledge would be vital for their effective conservation and management. Using own records and literature data, we provide a synthesis of the alliance Beckmannion eruciformis to characterise its associations floristically and ecologically in five regions along the river Tisza, East Hungary. We studied three associations of the alliance: (i) Agrostio stoloniferae-Alopecuretum pratensis, (ii) Agrostio stoloniferae-Beckmannietum eruciformis and (iii) Agrostio stoloniferae-Glycerietum pedicellatae. We found that solonetz meadow associations were separated along a moisture gradient with Agrostio stoloniferae-Alopecuretum pratensis at the drier end and Agrostio stoloniferae-Glycerietum pedicellateae at the wet end. This gradient was also justified by the distribution of the phytosociological groups. The proportion of species of Festuco-Brometea division was the highest in Agrostio stoloniferae-Alopecuretum pratensis, while the proportion of Cypero-Phragmitetea species was the highest in Agrostio stoloniferae-Glycerietum pedicellateae. Species of Puccinellio-Salicornetea had the highest proportion in Agrostio stoloniferae-Beckmannietum eruciformis, indicating the high soil salinity of this association. Our results suggest that Agrostio stoloniferae-Alopecuretum pratensis association plays an important role in preserving the continental flora elements of the surrounding dry grasslands. The ecological indicator values for soil moisture and salinity suggest that in case of the studied solonetz meadow associations, humidity increases with decreasing elevation, while salinity is highest at medium elevations. Our results suggest that Agrostio stoloniferae-Beckmannietum eruciformis is a transition towards salt marsh associations, while Agrostio stoloniferae-Glycerietum pedicellatae is a transition towards freshwater marshes. Our results show that preserving solonetz meadows is an important task for nature conservation as they have a crucial role in maintaining landscapescale species and habitat diversity and act as buffer zones around wetlands.
Escherichia coli α-hemolysin (HlyA) is a pore-forming protein of 110 kDa belonging to the family of RTX toxins. A hydrophobic region between the amino acid residues 238 and 410 in the N-terminal half of HlyA has previously been suggested to form hydrophobic and/or amphipathic α-helices and has been shown to be important for hemolytic activity and pore formation in biological and artificial membranes. The structure of the HlyA transmembrane channel is, however, largely unknown. For further investigation of the channel structure, we deleted in HlyA different stretches of amino acids that could form amphipathic β-strands according to secondary structure predictions (residues 71–110, 158–167, 180–203, and 264–286). These deletions resulted in HlyA mutants with strongly reduced hemolytic activity. Lipid bilayer measurements demonstrated that HlyAΔ71–110 and HlyAΔ264–286 formed channels with much smaller single-channel conductance than wildtype HlyA, whereas their channel-forming activity was virtually as high as that of the wildtype toxin. HlyAΔ158–167 and HlyAΔ180–203 were unable to form defined channels in lipid bilayers. Calculations based on the single-channel data indicated that the channels generated by HlyAΔ71–110 and HlyAΔ264–286 had a smaller size (diameter about 1.4 to 1.8 nm) than wildtype HlyA channels (diameter about 2.0 to 2.6 nm), suggesting that in these mutants part of the channel-forming domain was removed. Osmotic protection experiments with erythrocytes confirmed that HlyA, HlyAΔ71–110, and HlyAΔ264–286 form defined transmembrane pores and suggested channel diameters that largely agreed with those estimated from the single-channel data. Taken together, these results suggest that the channel-forming domain of HlyA might contain β-strands, possibly in addition to α-helical structures.
Here we present a formal description of Biremis panamae Barka, Witkowski et Weisenborn sp. nov., which was isolated from the marine littoral environment of the Pacific Ocean coast of Panama. The description is based on morphology (light and electron microscopy) and the rbcL, psbC and SSU sequences of one clone of this species. The new species is included in Biremis due to its morphological features; i.e. two marginal rows of foramina, chambered striae, and girdle composed of numerous punctate copulae. The new species also possesses a striated valve face which is not seen in most known representatives of marine littoral Biremis species. In this study we also present the relationship of Biremis to other taxa using morphology, DNA sequence data and observations of auxosporulation. Our results based on these three sources point to an evolutionary relationship between Biremis, Neidium and Scoliopleura. The unusual silicified incunabular caps present in them are known otherwise only in Muelleria, which is probably related to the Neidiaceae and Scoliotropidaceae. We also discuss the relationship between Biremis and the recently described Labellicula and Olifantiella.
Die Nationalsozialisten zerstörten seine Kindheit, raubten ihm die Jugend: Josef Buchmann überlebte die Konzentrationslager. Er gab nie auf, wurde ein erfolgreicher Unternehmer. Nachwuchsforscher und die Wissenschaft zu unterstützen, das sieht er – der selbst nicht studieren konnte – als "sein Lebenswerk" an.
In the framework of an interference setup in which only two outcomes are possible (such as in the case of a Mach–Zehnder interferometer), we discuss in a simple and pedagogical way the difference between a standard, unitary quantum mechanical evolution and the existence of a real collapse of the wavefunction. This is a central and not-yet resolved question of quantum mechanics and indeed of quantum field theory as well. Moreover, we also present the Elitzur–Vaidman bomb, the delayed choice experiment, and the effect of decoherence. In the end, we propose two simple experiments to visualize decoherence and to test the role of an entangled particle.