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Beatrix Maria Flad-Schnorrenberg 《Theoretical and Applied Climatology》1957,8(3-4):407-430
Zusammenfassung Bei der Bestimmung der täglich von Goldhamstern ausgeschiedenen Harnmenge wurden Schwankungen beobachtet, die nicht von einem vorhandenen Tages- oder Jahresrhythmus der Hamster verursacht sein können. Diese Schwankungen traten stets bei allen Tieren, die sich im Versuch befanden, gleichmäßig auf, obwohl sie stets unter konstanten Bedingungen gehalten wurden. Dabei wurde festgestellt, daß sich nur der Wassergehalt des Harnes und damit die Konzentration änderte, während die Menge der ausgeschiedenen festen Stoffe gleich blieb. Die Ursache für diese Mengenschwankungen des Harnes konnte in einer Beeinflussung der Wasserausscheidung durch meteorologische Vorgänge gefunden werden, und zwar wurde festgestellt, daß der Wechsel zwischen einer hauptsächlich durch tagesrhythmische Strahlung bestimmten Witterung und einer vorwiegend durch aperiodisch überlagerte Advektiveinflüsse bestimmten Wetterlage eine statistisch gesicherte Wirkung auf den Organismus ausübt. Dagegen konnte eine Beziehung zu einem einzelnen Wetterelement nicht festgestellt werden.
Mit 11 Textabbidlungen
Nach einer Dissertation der Naturwissenschaftlichen Fakultät der Universität München, 1956. 相似文献
Summary With the determination of the urine quantity daily secreted by gold-hamsters, variations have been registered, which cannot likely be caused by an existing daily or annual rhythm of hamsters. These variations have shown a uniform shape with all animals experimented with, though having been kept under constant conditions. It could be found that only the water-percentage of the urine and with it the concentration varied, while the quantity of secreted solid particles remained unchanged. The cause for these variations of the urine quantity could be traced in an influence of the meteorological situation on the water secretion; it has been stated that the change between a weather condition, which is mainly determined by the diurnal rhythm of radiation, and one mainly determined by superimposed aperiodical advective influences, shows an effect on the organism which is statistically significant. A relation, however, to a particular weather element could not be traced.
Résumé En déterminant la quntité d'urine journalière secrétée par des hamsters dorés, on a observé des variations qui ne pouvaient provenir d'un rythme journalier ou annuel propre aux hamsters Ces variations ont été observées uniformément chez tous les animaux avec lesquels on fit les expériences, bien qu'ils aient été soumis à des conditions constantes. On a remarqué que seul le pourcentage en eau, donc la concentration de l'urine variait, tandis que la quantité de matière solide restait la même. En outre, on a pu constater que ces variations de la quantité d'urine étaient causées par l'influence des conditions météorologiques sur la secrétion d'eau. Ainsi, on a observé que le changement d'une situation déterminée principalement par le rythme diurne du rayonnement à une situation déterminée surtout par des influences advectives apériodiques superposées, produisait un effet sur l'organisme; cet effect est significant au point de vue statistique, mais il n'a pas été possible d'établir une relation avec un élément météorologique déterminé.
Mit 11 Textabbidlungen
Nach einer Dissertation der Naturwissenschaftlichen Fakultät der Universität München, 1956. 相似文献
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Zusammenfassung 13 Klone von Blaualgen verschiedener taxonomischer Stellung (Chroococcales, Chamaesiphonales, Nostocales) und verschiedener
?kologischer Gruppen (Plankter, Litoralformen, Aerophyten schattiger und sonniger Standorte), wurden mit Gamma-und UV-Strahlen
behandelt. Plankter erwiesen sich unabh?ngig von ihrer taxonomischen Stellung als wenig widerstandsf?hig: Die maximale Gammastrahlentoleranz
betrug je nach Klon 65 bis 260 krad bei Bestrahlungszeiten von rund 10 bis 40 Minuten, die maximale UV_Strahlentoleranz belief
sich (mit einer Ausnahme) unter unseren Versuchsbedingungen auf eine Bestrahlungszeit von 32 Minuten. Begleitbakterien tolerierten
durchwegs h?here Strahlendosen. Dagegen erwiesen sich Aerophyten bzw. Lithophyten von Standorten mit extremem natürlichem
Strahlungsklima auch im Experiment als sehr resistent. So überlebtenChamaesiphon polonicus undScytonema burmanicum siebenstündige Exposition in Gammastrahlen (totale Dosis 2500 krad) sowie vierstündige UV-Bestrahlung. Begleitbakterien überlebten
zwar die UV-Behandlung, nicht aber die hohen Gammastrahlendosen. Behandlung mit Gammastrahlen eignet sich daher zur Gewinnung
axenischer Kulturen von Cyanophyten extremer Naturstandorte.
Mehrere Monate alte axenische Kulturen vonScytonema burmanicum und vonS. lyngbyoides riechen übel, w?hrend bakterienhaltige Kulturen geruchlos bleiben. Vermutlich bauen die Begleitbakterien von den Algen ausgeschiedene,
übelriechende Stoffwechselprodukte zu geruchlosen Verbindungen ab.
Summary Thirteen strains of blue-green algae including members of the Chroococcales, Chamaesiphonales and Nostocales and belonging to various ecological groups have been exposed to various doses of gamma and UV radiation. Tolerances were independent of the taxonomic position but correlated with the ecological behaviour of the taxa involved. While planktonic species were quite sensitive to both UV and gamma radiation (maximum tolerance in the range of 65 to 260 krad) aerophytic and lithophytic species tolerated up to more than 2500 krad of gamma radiation and more than 4 hours of exposition to UV radiation. In cultures of planktonic species, gamma radiation killed the algae prior to the associated bacteria so that no axenic cultures could be obtained. In some cultures of aerophytic and lithophytic taxa however, bacteria were killed prior to the algae. Thus, axenic cultures of these strains could be obtained. Old axenic cultures ofScytonema burmanicum and ofS. lyngbyoides display a bad smell, whereas cultures with bacteria are odourless. Probably, the bacteria are reducing to odourless compounds the smelling substances excreted by the algae.
Résumé Treize souches cloniques de Cyanophycées d’eau douce appartenant aux ordres des Chroococcales, des Chamaesiphonales et des Nostocales et représentant divers types écologiques à savoir des formes du plancton et du littoral ainsi que des espèces saxicoles aériennes et subaériennes de habitats ombreux et fort ensoleillés ont été traité aux rayons et UV. Les espèces planctoniques se montraient peu résistantes, indépendemment de leur position taxonomique: Dans nos conditions, elles supportaient au maximum 32 minutes d’irradiation de rayons UV, et, selon la souche clonique, de 65 à 260 krad de rayons gamma. Les bactéries accompagnant les algues supportaient partout des doses d’irradiation plus élevées. Par contre, les espèces saxicoles provenant de stations aériennes ou subaériennes se montraient très résistantes.Chamaesiphon polonicus etScytonema burmanicum par exemple supportaient dans nos conditions une irradiation UV de 4 heures et une exposition aux rayons gamma de 6 heures (dose totale: 2500 krad). Les bactéries accompagnant ces espèces supportaient les rayons UV, mais non les rayons gamma. Le traitement avec des rayons gamma peut donc aboutir à des cultures axéniques de Cyanophycées d’habitats aériens ou subaériens. Les cultures axéniques deScytonema burmanicum et deS. lyngbyoides agées de quelques mois sentent mauvais, tandis que les cultures parallèles dont les algues sont accompagnées de bactéries restent sans odeur. Il semble que les bactéries décomposent les substances d’odeur désagréable produites par les deux espèces.相似文献
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Magnetic susceptibility as a possible correlation tool in Quaternary alluvial stratigraphy 
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下载免费PDF全文 Zoltán Püspöki István J. Kovács Tamás Fancsik Annamária Nádor Edit Thamó‐Bozsó Ágnes Tóth‐Makk Beatrix Udvardi Péter Kónya Judit Füri Zsolt Bendő László Zilahi‐Sebess Ferenc Stercel Ágnes Gulyás Richard W. Mcintosh 《Boreas: An International Journal of Quaternary Research》2016,45(4):861-875
Correlation of the fluvial magnetic susceptibility (MS) record of borehole Devavanya‐1 in the Körös Basin (eastern Hungary) with Chinese aeolian MS records (Jingbian, Lingtai) and the marine δ18O record from the Equatorial Pacific (V28‐239) is established here based on cross‐correlations and singular spectral analysis. A basin‐scale well‐to‐well correlation based on magnetic susceptibility records was also performed involving unpublished cores. To refine the age model, a Monte Carlo simulation was conducted using the Chinese Jingbian section as a tuning target. Spectral analysis of the tuned record revealed c. 400, c. 100 and c. 41 ka cycles over the 2.5 million years of the Quaternary fluvial succession. To ensure a complementary palaeoclimate proxy, the full width at half maximum of smectites was measured as a facies‐independent indicator of weathering intensity. This investigation was carried out on a subset of samples involved in MS measurements representing a c. 400 ka time interval across the top of the Olduvai subchron. A phase‐shift between MS and weathering intensity recorded in the clay mineralogy indicates different response times of the considered proxies. The fluvial MS record is determined by the climatic control on delivery and preservation of magnetic minerals, mainly of magnetite. Under cold‐and‐dry climate these minerals were released owing to frost shattering in the adjacent hinterlands and were transported to alluvial plains in the early postglacial periods thanks to the increasing discharge of rivers. With further warming the weathering‐sensitive magnetic minerals soon disappeared from the soils of the catchment area and thus from the fluvial load. As a result, in fluvial successions early postglacial warmings are expressed by the occurrences of MS maxima (magnetic episodes), while the palaeotemperature maximum and the subsequent cooling remain concealed within the tract of low MS values. The early postglacial magnetic episodes may serve as ideal stratigraphical markers in regional and global correlations. 相似文献
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István Kovács Attila Demény György Czuppon Christophe Lécuyer Francois Fourel Qun-Ke Xia Jia Liu Zsanett Pintér Edit Király Kálmán Török Ábel Szabó Etienne Deloule György Falus Tamás Fancsik Zoltán Zajacz Judit Sándorné Kovács Beatrix Udvardi 《Contributions to Mineralogy and Petrology》2016,171(5):38
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Juraj Majzlan Hannes Schlicht Maria Wierzbicka-Wieczorek Gerald Giester Herbert Pöllmann Beatrix Brömme Stephen Doyle Gernot Buth Christian Bender Koch 《Mineralogy and Petrology》2013,107(2):221-233
Voltaite is a mineral of fumaroles, solfatares, coal-fire gas vents, and acid-mine drainage systems. The nominal composition is K2Fe5 2+Fe3 3+Al(SO4)12·18H2O and the nominal symmetry is cubic, $Fd\overline{3}c$ . The tetragonal (I41/acd) superstructure of voltaite is known as the mineral pertlikite. In this study, we investigated 22 synthetic voltaite samples in which Fe2+ was partially or completely replaced by Mg, Zn, Mn, or Cd, by single-crystal and powder X-ray diffraction (both in-house and synchrotron). Two samples contained NH4 + instead of K+. The structure of voltaite is based on a framework defined by kröhnkite-like heteropolyhedral chains which host both M3+ and M2+ in octahedral coordination. Unit cell dimensions of the end-members scale almost linearly with the size of M2+. In the Fe2+-Mg-Zn solid solutions, the Fe2+-Mg and Fe2+-Zn solutions are linear (ideal) in terms of their lattice-parameter variations. The Mg-Zn solid solution, however, is strongly non-ideal. A detailed analysis of the topology of the chains showed that this behavior originates in expansion and contraction of individual M2+-O bonds within the chains. In the Mg-Zn solid solution, some of the M2+-O bonds expand while none contract. In the other solid solutions, expansion of some M2+-O bonds is always compensated by contraction of the other ones. Parts of the nominally cubic crystals are optically anisotropic and their symmetry is found to be tetragonal by single crystal X-ray diffraction measurements. The coexistence of cubic and tetragonal sectors within a single crystal without any detectable difference in their chemical composition is difficult to explain in terms of growth of such composite crystals. Mössbauer and infrared spectra collected on our synthetic crystals conform with previously published data. 相似文献
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Scaling Issues in Forest Succession Modelling 总被引：5，自引：0，他引：5
Harald Bugmann Marcus Lindner Petra Lasch Michael Flechsig Beatrix Ebert Wolfgang Cramer 《Climatic change》2000,44(3):265-289
This paper reviews scaling issues in forest succession modelling, focusing on forest gap models. Two modes of scaling are distinguished: (1) implicit scaling, i.e. taking scale-dependent features into account while developing model equations, and (2) explicit scaling, i.e. using procedures that typically involve numerical simulation to scale up the response of a local model in space and/or time. Special attention is paid to spatial upscaling methods, and downscaling is covered with respect to deriving scenarios of climatic change to drive gap models in impact assessments. When examining the equations used to represent ecological processes in forest gap models, it becomes evident that implicit scaling is relevant, but has not always been fully taken into consideration. A categorization from the literature is used to distinguish four methods for explicit upscaling of ecological models in space: (1) Lumping, (2) Direct extrapolation, (3) Extrapolation by expected value, and (4) Explicit integration. Examples from gap model studies are used to elaborate the potential and limitations of these methods, showing that upscaling to areas as large as 3000 km2 is possible, given that there are no significant disturbances such as fires or insect outbreaks at the landscape scale. Regarding temporal upscaling, we find that it is important to consider migrational lags, i.e. limited availability of propagules, if one wants to assess the transient behaviour of forests in a changing climate, specifically with respect to carbon storage and the associated feedbacks to the atmospheric CO2 content. Regarding downscaling, the ecological effects of different climate scenarios for the year 2100 were compared at a range of sites in central Europe. The derivation of the scenarios is based on (1) imposing GCM grid-cell average changes of temperature and precipitation on the local weather records; (2) a qualitative downscaling technique applied by the IPCC for central and southern Europe; and (3) statistical downscaling relating large-scale circulation patterns to local weather records. Widely different forest compositions may be obtained depending on the local climate scenario, suggesting that the downscaling issue is quite important for assessments of the ecological impacts of climatic change on forests. 相似文献
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