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251.
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Michael von Reinhardt 《Die Naturwissenschaften》1969,56(12):581-590
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W. von Thun 《Marine Biology》1967,1(1):36-39
Domorganus oligochaetophilus n.sp., a new representative of the Cylindrolaiminae Micoletzky (1922) sensu De Coninck (1965) is described. The adults live as endo-parasites in the intestine of littoral oligochaetes (Lumbricillus lineatus O. F. Müller 1774) from the Kieler Bucht (western Baltic Sea). This is the first endo-parasitic record in marine invertebrates of the Nematoda Adenophorea. The new species is characterized morphologically by: 4 cephalic setae, a very small buccalcavity without any sclerotized structures, an esophagus, with 2 bulbs, an excretory pore located posterior to the esophagus, reflexed diorchic ovaria, outstretched diochic testes, and 1 vesicular pre-anal organ in the male. Observations on living specimens show that the parasites live free in the intestinal lumen or are fixed by their spinneret glands at the intestinal wall of their hosts. Their food consists apparently of particulate intestinal contents. 相似文献
257.
von Helversen O Heller KG Mayer F Nemeth A Volleth M Gombkötö P 《Die Naturwissenschaften》2001,88(5):217-223
The analysis of morphological, behavioural and genetic characters of whiskered bats revealed a new European bat species within the family Vespertilionidae. We describe the morphology, karyology, genetic similarity, ecology and distribution of Myotis alcathoe n. sp. It closely resembles Myotis mystacinus, Myotis brandtii and Myotis ikonnikovi in morphology, but all four species show clear genetic differences in two mitochondrial genes (ND1 and 12S rRNA). Myotis alcathoe n. sp. is the smallest species among the European whiskered bats and uses the highest-frequency echolocation calls of all the European Myotis species. It prefers to hunt in small valleys with deciduous trees and flowing water, which is an endangered habitat. Records from Greece and Hungary indicate a distribution range in south-eastern Europe. 相似文献
258.
M. Weller P. Plessing H. Rentsch J. Lattauschke W. von Hoyningen-Huene 《Atmospheric environment (Oxford, England : 1994)》2000,34(29-30)
With the development of satellite experiments supplementary and validating ground-based measurements are gaining growing importance for the inference and evaluation of radiation-related aerosol parameters. Both kinds of measurements have been conducted and interpreted mainly under globally or locally restricted aspects for a limited time period only. Results are presented from four rural regions (coastal zone, lowlands, highlands, high mountain); they are column-related aerosol parameters, deduced from monitoring programs of spectral aerosol optical depth (AOD) as well as almucantar sky irradiance measurements. After 13 years of continuous measurements of trends and variations in aerosol optical depths, these results are based on 5 years of data collection (1994–1998). There are significant differences among the parameters of the four regions when related to the inversion method of the AOD spectra. A clear interdependence was found between all column-related parameters and the real part of the refractive index, which in turn depends on the chosen retrieval method. The differences among the four regions are characterized mainly by their different altitudes, with relative humidity being responsible for their internal variation. An increase in the relative humidity from 35 to 55–60% influences the most interesting parameters such as refractive index (real part), hemispheric backscattered fraction b, and direct radiative forcing ΔF as follows: The real part of the refractive index decreases from 1.6±0.05 to 1.42±0.04, b decreases by 8–10%, and, due to the increase in AOD, ΔF increases by about 20% in the spectral region 0.4–1.0 μm. The quantities of the parameters depend on the retrieval methods too. 相似文献
259.
Werner von Bloh Christine Bounama Klaus EisenackBrigitte Knopf Oliver Walkenhorst 《Ecological modelling》2008
To determine the influence of the biosphere on weathering we use a dynamic model of the global carbon cycle. It takes into account the most important processes for the long-term evolution of the Earth. The model is solved under a slowly changing environment of increasing solar luminosity and volcanic activity and continental area. By comparing the model results for the global average temperature with data derived from δ18O values from cherts it is possible to quantify the biogenic enhancement factor of weathering. For this purpose a newly developed inverse viability method is applied, which allows for calculating the range of possible biogenic enhancement factors consistent with the data. We find that in the Precambrian the weathering was 5.4 times lower than in the Phanerozoic era. This supports the hypothesis that the Cambrian explosion was caused by a positive feedback between the spread of biosphere, increased silicate weathering, and a consequent cooling of the climate. 相似文献
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