共查询到20条相似文献,搜索用时 9 毫秒
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Achim Kostrzewa Dr. 《当今生物学》2010,40(2):102-109
The future of penguin population development in the Western Antarctic Peninsula (= WAP) is largely depending on ecological factors like food availability (mostly krill) due to primary production of algae which itself depends on sea ice conditions, water‐ and air temperature and salinity. The extraordinary rise in temperature in the WAP area seems to cause a change in population numbers of Adelie and Gentoo Penguins: Adelies are declining in the north and Gentoos were occupying these sites instead. Gentoos have already reached the southern polar circle. These trends occurred in parallel with regional long‐term warming and significant reduction in sea ice extent. There is a lack of available information for penguin populations breeding possibly more south in the WAP area. We still have large gaps in our present knowledge in Adelies and Emperor Penguins southernmost breeding distribution. 相似文献
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Achim Kostrzewa 《当今生物学》2020,50(1):44-51
Emperor Pinguin – a bird of superlative The antarctic ecosystem is home of 200 million seabirds. 26 million of them belong to the penguins and only 600.000 are Emperor Penguins. They breed along the remote coasts of Antarctica. Their first colony was discovered in 1902. In the course of the 1950ies more colonies were detected and today with the help of satellite technique we know more than 54 in total. The breeding cycle starts during winter, when a 1.000 kilometer sea ice belt surrounds the continent. Emperor Penguins use Polynjas during this time to get access to the food sources in the sea. During incubation and breeding they are very hard to study due to stormy weather and temperatures of sometimes below minus 30° Celsius. From October onwards the first big icebreakers are capable to reach some of these places and biologists can start to study breeding success by counting chicks and adults. The few best monitored colonies are in the reach of Antarctic winter stations. Remote sensing of faeces stain on the ice give an introspection of the spacing of colonies all over the coasts. Counts in the colonies give figures of population sizes in relation to faeces covered areas. So we got a rough idea about the number of individuals. Satellite imaging over the last 40 years has provided data on the sea and glacier ice loss: Most loss is to be found in western Antarctica, but also in eastern Antarctica we can find more and more melting due to raising temperatures. 相似文献
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Dr. Hannes Petrischak 《当今生物学》2012,42(5):310-318
Excursion: montane meadows and forests in the southern Hunsrück Several ridges of the hard Taunus quartzite run parallel southwest‐northeast through the southern part of the Hunsrück. These ridges are densely wooded. The history of the forests is closely connected with iron ore smelting in this region from the Celtic era to the 19th century. Poor montane meadows have developed from extensive use over the centuries. They show a remarkable richness in species, but they are endangered by abandonment or intensifying use. The Nardus grasslands have special significance in this context. Arnica montana, Narcissus pseudonarcissus and Meum athamanticum are among the botanical highlights. Many rare and, in some cases, severely threatened butterfly species can be found in high numbers of individuals in these habitats. 相似文献
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Invasion of exotic mosquitos in Germany The scientists of the “German Mosquito Control Association” (KABS) and the University Heidelberg detected between 1995 and 2011 four new species of mosquitoes as neozoa for Germany. Aedes albopictus and Ochlerotatus j. japonicus have been introduced to new territories such as Germany in the context of globalization with trade goods, increased mobility of humans by means of vehicles. In particular the spread of the originally tropical species Ae. albopictus is favored by global warming. The rapid spread of Ae. albopictus and Oc. j. japonicus and the related risk of transmission of human pathogens, especially of arboviruses, increased the awareness of scientists, health authorities and the public and led to an intensive surveillance program for exotic mosquito species in Germany. 相似文献
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Bánk Beszteri Charlotte Havermans Holger Auel Wilhelm Hagen Scarlett Trimborn 《当今生物学》2020,50(1):28-35
Polar plankton Climatic changes such as the rise in temperature and ocean acidification have already severely impacted the planktonic life of the Southern Ocean. Our studies demonstrate that Antarctic plankton is changing. Large diatoms contribute most to primary production in the current Southern Ocean, whereas in the future small flagellates could become more abundant. Also zooplankton is impacted. Recent studies reveal a shift from a krill- to a salp-dominated food web in the Southern Ocean and the replacement of polar cold-water species by warm-tolerant species of adjacent regions. 相似文献
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Eckehart Jger 《Plant biology (Stuttgart, Germany)》1968,81(8):397-408
Die heutige Verbreitung der Vegetationsformationen der Dunklen Taiga und des sommergrünen Breitlaubwaldes läßt sich auch im Detail weitgehend durch die aktuellen Klimafaktoren erklären. Auch das Ausfallen des Gürtels der sommergrünen Laubwälder in Nordwestamerika steht damit im Einklang. Das Fehlen ozeanischer Lorbeer-Nadelwälder im atlantischen Europa hat seine Ursache dagegen im historisch bedingten Artenpotential. Das klimatisch-potentielle europäische Areal dieser Wälder wird von sommergrünen Breitlaubwäldern ausgefüllt. Die klimatischen Areale der Dunklen Taiga bzw. der sommergrünen Breitlaubwälder stimmen gut mit den Arealen der beiden Sektionen von Circaea überein, die damit ein Beispiel für eine charakteristisch taxonomisch-geographische Sippendifferenzierung geben. 相似文献
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Irenus Eibl-Eibesfeldt Wolfgang Wickler 《Ethology : formerly Zeitschrift fur Tierpsychologie》1968,25(6):719-726
Ein althergebrachter Typ südbalinesischer Statuen, “Mömmedi” genannt, wird beschrieben. Untersuchungen an Ort und Stelle ergaben, daß es zum Schutz von Haus und Eigentum aufgestellte Wächterfiguren sind. Sie senden mehrere soziale Drohsignale, nämlich das Präsentieren des erigierten Phallus und manchmal auch des Analfeldes, eine offen hochgehaltene Hand und ein Drohgesicht. 相似文献
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Walter Pflumm 《当今生物学》1985,15(5):137-140
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Ludwig Beck 《当今生物学》1993,23(5):286-294
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