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Zwischen dem Nordrand der Mittelgebirge und den nordwestdeutschen Altmoränengebieten liegt eine bis 30 km breite Lößzone, die als altbesiedeltes Gebiet eine stark ausgeräumte Kulturlandschaft darstellt. Die Restflächen der Wälder betragen nur noch 5%, zeigen aber eine breite Amplitude verschiedener Waldgesellschaften. In den eigentlichen Lößbereichen wachsen vor allem Eichen-Hainbuchenwälder verschiedener Ausprägung von sehr artenarmen bis zu artenreichen Beständen. Sie gehören zum Stellario-Carpinetum Oberd. 1957, das sich in 2 Subass.-Gruppen mit 4 Subassoziationen und mehrere Varianten gliedern lässt. Einige Wälder nasser Standorte lassen sich dem Alno-Ulmion zuordnen.
The Holomitrium-complex (consisting of Holomitrium, Eucamptodontopsis, and Schliephackea) is a group of closely related genera in the Dicranaceae characterized by five features: 1. a strong single costa, 2. well developed alar cells, 3. long, sheathing perichaetial leaves, 4. erect capsules, and 5. undivided peristome teeth. Holomitrium sinuosum is newly described. Dicranoloma brittonae is transferred to Eucamptodontopsis. Holomitrium standleyi is a synonym of H. arboreum. Breedlovea chiapensis is a synonym of Holomitrium pulchellum and the genus Breedlovea is placed into the synonymy of Holomitrium.
Crossomitrium is a genus of neotropical, essentially epiphyllous mosses. The genus consists of six species that are distributed in two sections: section Crossomitrium (C. acuminatum, C. patrisiae, and C. scabrisetum) and section Cormophila (C. epiphyllum, C. saprophilum, and C. sintenisii). Section Crossomitrium is characterized by 1. plants nearly always on leaves or twigs, 2. lateral leaves oblongacuminate and widest below the middle, 3. leaves when dry that arch from an erect base downward to the substrate and, 4. the presence of specialized brood branches that are closely adnate to the substrate and have tightly imbricate leaves. Section Cormophila is characterized by 1. plants growing on rocks and tree trunks as well as on leaves, 2. lateral leaves oval to obovate, acute to apiculate and widest above the middle, 3. leaves when dry flattened to the substrate and, 4. the presence of erect, specialized brood branches that have leaves spreading on all sides. Crossomitrium is placed in the Hookeriaceae (sensu Whittemore & Allen, 1989) on the basis of its branched stems, ecostate leaves, straight, unbranched rhizoids that are tightly clustered just posterior to the leaf bases, 2-celled axillary hairs and weakly pigmented stem cortex. Within the Hookeriaceae Crossomitrium is considered close to the genus Lepidopilum by virtue of 1. its peristome which is hydrocastique and has a high basal membrane, 2. the spinose setae of C.acuminatum and C. scabrisetum, 3. the irregular subdivision of its stomatal guard cells (including the presence of stomates at the base of raised pustules), 4. leaves doubly serrulate by the projecting ends of contiguous marginal cells, 6. absence of a stem central strand. It differs from Lepidopilum in its 1. symmetric, ecostate leaves, 2. calyptra fimbriate by downward projecting, multicellular hairs that arise from the margins of the calyptra, 3. collenchymatous exothecial cells, 4. the presence of broodbodies on specialized brood branches as well as in clusters just below the junction of the leaf with the stem.
A survey of the freshwater fishes of the Sepik River system of northern Papua New Guinea was undertaken by the authors between 1978 and 1985 with the use of gill nets and rotenone, and also by monitoring catches at local villages and markets. We also include records of past expeditions, namely that of the Dutch naturalist Gjellerup in 1910 and the yacht Illyria in 1929. The total known freshwater fauna as reported herein consists of 57 species in 35 genera and 23 families. The fauna is typical of other sections of New Guinea and northern Australia in that it is dominated by catfishes (Ariidae and Plotosidae), rainbow fishes (Melanotaeniidae), gudgeons (Eleotrididae) and gobies (Gobiidae) which collectively comprise 57 percent of the total species. With the exception of 22 widely distributed species that are frequently estuarine dwellers and are confined to the lower Sepik, the fishes are strongly endemic, either to the Sepik-Ramu drainages (which interconnect during Doods), or the "intermontane trough" composed of the combined Markham, Ramu, Sepik, and Mamberamo systems. Individual accounts, including brief descriptions and information pertaining to habitat, distribution and biology are included for each species. In addition illustrations are provided for many of the endemic species.
Forty-two chemicals were tested for their ability to induce cytogenetic change in Chinese hamster ovary cells using assays for chromosome aberrations (ABS) and sister chromatid exchanges (SCE). These chemicals were included in the National Toxicology Program's evaluation of the ability of four in vitro short-term genetic toxicity assays to distinguish between rodent carcinogens and noncarcinogens. The conclusions of this comparison are presented in Zeiger et al. [Zeiger E, Haseman JK, Shelby MD, Margolin BH, Tennant RW (1990): [Environ Molec Mutagen 16(Suppl 18): 1-14]. The in vitro cytogenetic testing was conducted at four laboratories, each using a standard protocol to evaluate coded chemicals with and without exogenous metabolic activation. Most chemicals were tested in a single laboratory; however, two chemicals, tribromomethane and p-chloroaniline, were tested at two laboratories as part of an interlaboratory comparison. Four chemicals (CI. basic red 9 HCI, 2-mercaptobenzothiazole, oxytetracycline HCI, and rotenone) were tested for SCE in one laboratory and in a different laboratory for ABS. Tetrakis(hydroxymethyl)phosphonium sulfate was tested at one laboratory and the chloride form was tested at a different laboratory. Twenty-five of the 42 chemicals tested induced SCE. Sixteen of these also induced ABS; all chemicals that induced ABS also induced SCE. There was approximately 79"10 reproducibility of results in repeat tests, thus, we conclude that this protocol is effective and reproducible in detecting ABS and SCE.
The magnetic dipole scattering of neutrinos by the electrostatic potentials of single atoms as well as crystals is investigated. It is shown that scattering by a rigid cubic lattice can amplify the neutrino-atom cross section by a factor of N1/3, N being the number of scatterers. However, comparing the results with typical weak-interaction cross sections, the effect seems to be not observable in experiment.
1989 wurde mit Barber-Fallen und Handaufsammlungen die Carabidenfauna einer bäuerlichen Kulturlandschaft mit Bächen, Hecken, kleinen Wäldern, Äckern, Wiesen und Weiden untersucht. Insgesamt konnten 102 Arten nachgewiesen werden. Oie Habitatbindung und Verbreitung einiger Arten werden diskutiert. Vorschläge zum Erhalt der artenreichen Carabidenfauna werden gegeben.
Die Halophytenvegetation des Pikrolimni-Sees (Höhenlage 47 m ü. Meer) wird phytosoziologisch beschrieben. Die sieben Pflanzengesellschaften (Crypsidetum aculeatae, Suaedetum maritimae, Camphorosmetum annuae, Plantaginetum coronopi, Limonio-Spergularietum, Elymetum elongati, Puccinellietum convolutae), die rings um den See erkannt wurden, sind sehr artenarm und werden in die eigenartige Salzvegetation des balkanischen Binnenlandes eingegliedert. Bodenanalysen (Bestimmung von pH, CaCO3, NaCl) geben eine allgemeine Bewertung der Bodeneigenschaften von fünf Gesellschaftssubstraten.
In der Provinz Bozen gibt es in der montanen Stufe der Alpen mehrere Gesellschaften der Klassen Phragmito-Magnocaricetea, Scheuzerio-Caricetea fuscae und Molinio-Arrhenatheretea (Ordnung Molinietalia). Untersucht wurden der östliche Teil der Ortler Gruppe, die Sarntaler Alpen und der westliche Teil der Dolomiten. Diese Gesellschaften, von denen sich die meisten auch in anderen orographischen Einheiten der Alpen finden, kommen im Untersuchungsgebiet spärlich vor, und zwar in Quell-Lagen und von Grundwasser beeinflussten Bachauen glazialen Ursprungs. Es handelt sich um folgende Assoziationen: Caricetum rostratae, Caricetum paniculatae, Caricetum fuscae, Eleocharitetum pauciflorae, Primulo-Schoenetum ferruginei, Caricetum davallianae, Trollio-Molinietum caerulea, Chaerophyllo hirsuti-Crepidetum paludosae, Crepido paludosae-Trollietum altissimi, Trollio altissimi-Cirsietum heterophylli und Filipendulo-Menthetum longifoliae.
Das Gentiano-Koelerietum ist eine typische Pflanzengesellschaft der Rinder- und Schafhutungen auf kalkreichem oder kalkarmem, aber basenreichem Gestein. Die Standorte der Gesellschaft entsprechen zumeist den natürlichen Wuchsorten des Platterbsen- oder des Seggen-Buchen-Waldes. Extensive Beweidung, fehlende Düngung (geringes Stickstoffangebot), hoher Besonnungsgrad und eine mehr oder minder ausgeprägte Flachgründigkeit des kalk- beziehungsweise basenreichen Bodens sind die wesentlichen Standortsvoraussetzungen dieser Gesellschaft.