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Micropalaeontological data from NEP1, NEP2, NEP3, Nördlingen, southern Germany

Three soil profiles from the Eger floodplain in Nördlingen in southern Germany (NEP1, NEP2 and NEP3), were sampled and micropalaeontological data were collected. Samples were weighted, wet sieved through 125 µm, dried on a heating plate at <60°C, and studied under a stereomicroscope at the University of Jena, Germany. Some specific particles of interest (plant remains, charcoal, mollusc and brick fragments) were assessed in semiquantitative abundance classes for each sample, while all other particles of interest were picked and counted in absolute abundances. This includes Mollusca, Ostracoda, reworked microfossils, macrobotanical remains (seeds and fruits), and insect and bone fragments. Where possible, taxa were identified down to species level. The data allow to develop a palaeoenvironmental reconstruction through the soil profiles, and can provide information on fluvial activity, landscape development and the general hydrological situation through time. It can in combination with other data corroborate the correlation of the three profiles and the interpretation of the depositional history in the Eger floodplain.

Vertical distribution in the sediment of the different animal groups found in station CON01-433 (Vydrino Shoulder) in the abyssal zone of Lake Baikal, expressed as the number of individuals per m2.

The vertical distribution of organisms in the sediment indicates that animals can be present as deep as 15 cm although at very low abundance at such depths (Fig. 4, Fig. 5 and Fig. 6). Oligochaetes and nematods are the only groups able to deeply penetrate into the sediment at significant densities (Fig. 4) in contrast to all other groups, which stay closer to the sediment surface. Maximal densities however seem to shift to the sediment surface with increasing bathymetric depth, as suggested in Fig. 5 and Fig. 6, so that all animal groups are more concentrated near the surface in the deepest parts of Lake Baikal. In such case, the depth of sediment mixing due to bioturbation appears to decrease with increasing bathymetric depth (Fig. 2b).

Vertical distribution in the sediment of the different animal groups found in station CON01-416 (Continent Ridge) in the abyssal zone of Lake Baikal, expressed as the number of individuals per m2.

The vertical distribution of organisms in the sediment indicates that animals can be present as deep as 15 cm although at very low abundance at such depths (Fig. 4, Fig. 5 and Fig. 6). Oligochaetes and nematods are the only groups able to deeply penetrate into the sediment at significant densities (Fig. 4) in contrast to all other groups, which stay closer to the sediment surface. Maximal densities however seem to shift to the sediment surface with increasing bathymetric depth, as suggested in Fig. 5 and Fig. 6, so that all animal groups are more concentrated near the surface in the deepest parts of Lake Baikal. In such case, the depth of sediment mixing due to bioturbation appears to decrease with increasing bathymetric depth (Fig. 2b).

Vertical distribution in the sediment of the different animal groups found in station CON01-427 (Posolskoe Bank) in the dimictic zone of Lake Baikal, expressed as the number of individuals per m2.

The vertical distribution of organisms in the sediment indicates that animals can be present as deep as 15 cm although at very low abundance at such depths (Fig. 4, Fig. 5 and Fig. 6). Oligochaetes and nematods are the only groups able to deeply penetrate into the sediment at significant densities (Fig. 4) in contrast to all other groups, which stay closer to the sediment surface. Maximal densities however seem to shift to the sediment surface with increasing bathymetric depth, as suggested in Fig. 5 and Fig. 6, so that all animal groups are more concentrated near the surface in the deepest parts of Lake Baikal. In such case, the depth of sediment mixing due to bioturbation appears to decrease with increasing bathymetric depth (Fig. 2b).

Densities of benthic taxa with depth (CON 01-01 and CON 01-04 expeditions).

In all abyssal stations, densities are never over an average of c. 3100 individuals m−2 (Fig. 3, Table 1). In contrast, the shallow station (CON01-427, Posolskoe Bank) harbours the highest observed densities (oligochaetes reach densities as high as 13573 individuals m−2 on average). Gammarids are present in this latter station at 128 m deep, while they are absent from all deep stations. The presence of some groups is anecdotal, such as Hydrachnidia (one specimen in a core at 388 m and two specimens in a core at 625 m) and chironomid larvae (two larvae in a core at 625 m). Interestingly, the two deepest Vydrino cores (CON01-105-7, 600 m, and CON01-106-3, 700 m) are virtually free from animals, suggesting that these stations are perhaps the best choice for the study of stratigraphy and climate proxies.

Bestandsaufnahme der Grundwasserfauna Baden-Wuerttembergs unter besonderer Beruecksichtigung des Vergleichs zweier Grundwasserlandschaften

Bestandsaufnahme der Grundwasserfauna durch qualitative Probennahme (Ufergrabungen, Brunnenproben) entlang Rhein, Donau, Neckar und Zufluessen, Tauber; Aufbau einer kleinen Datenbank mit allen die Grundwassertiere Baden-Wuerttembergs betreffenden Informationen: - Vergleich der Besiedelung zweier chemisch gut unterscheidbarer Grundwasserlandschaften (Kiese und Sande des Oberrheingrabens, Kristallin des Schwarzwaldes). - Vergleich der Besiedelung der Kiese und Sande des Oberrheingrabens in einem anthropogen unbeeinflussten und einem durch einen Schadensfall oder eine Altlast mit definierten Schadstoffen belasteten Bereich. - Laborbeobachtungen an charakteristischen Grundwassertieren Baden-Wuerttembergs. Das Artenspektrum der bislang bestimmten Fauna aus dem quartaeren und kristallinen Grundwasser konnte von 64 Arten 1993 auf 104 Arten erhoeht werden. Neben den Copepoda (Cyclopoida, Harpacticoida) wurden Amphipoda (Niphargidae), Asellota und Ostracorda bearbeitet. Mit der Auswertung der grundwasserlandschaftlichen Relevanz ihres Auftretens wurde begonnen. Die Grundwasserbibliothek wurde laufend erweitert und enthaelt nun eine zusaetzliche Sammlung der wichtigsten Niphargiden-Beschreibungen. Elektronenmikroskopische Untersuchungen an stygobionten Krebsen (Syncarida) wurden erweitert. Neben dem Maxillennephridium zeigte auch der Darmtrakt spezielle Adaptionen an die schlanke Koerperform und das Leben im Interstitial.

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