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91.
Ole Humlum Niels Nielsen Morten Rasch Birger Ulf Hansen Sofus Christiansen 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(1):119-129
In October 1990 an automatic meteorological station was established at the Arctic Station (69°15'N, 53°31'W), Qeqertarsuaq (Godhavn), Central West Greenland, The station register parameters each 20 min, and the parameters have been described in an earlier paper in this journal by Nielsen et al. (1995). The present paper summarises main points of the climate during 1995. Concentrational agriculture, defined as types of agriculture based on local concentration of plant nutrients, encompasses two main types: shifting cultivation and infield-outfield systems. They may ecologically be characterised by their mode of concentration: either by a vertical or a horisontal transfer (‘pumping’) of nutrients, respectively. The use of the general term ‘concentrational agriculture’ for the two forms is advocated by demonstrating that functional substitution of one by the other is possible, and by showing that the one type theoretically can be derived from the other. Historically, infield-outfield systems are supposed to be developed from some form of shifting cultivation. Kort beretning om virksomheden i 1995 Justering af medlemskredsen. I forbindelse med valg af repræsentanter fandt en justering af repræsentationsområder sled (Århus Universilet har ikke længere fagområdet ‘kulturgeografi’). Videnskabernes Selskab har i samme forbindelse bifaldet, at fire observatører, repræsenterende undervisningstrinene i geografi deltager i møderne. 相似文献
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We retrieved a lake sediment record from an oligosaline, meromictic lake in southwest Greenland. The record spans the last
8,200 cal. years and was radiocarbon dated and analysed for macroscopic remains of plants and animals. The record extends
the known history of several invertebrate species back in time, and provides minimum ages for their immigration to Greenland
after the last deglaciation. Shells of the ostracod Ilyocypris bradyi were found in sediments dated to the time interval c. 7,000–6,500 cal. years BP. Shells of this species were found previously in a nearby oligosaline lake, where its occurrence
was dated to about the same short time interval. The species is a thermophilous, non-arctic taxon that is absent from the
present day Greenland fauna, and we suggest that its former occurrence in west Greenland marks the peak of the Holocene thermal
maximum. This is in agreement with other records from Greenland. 相似文献
95.
John Davis Jakeman Ole M. Nielsen Kristy Van Putten Richard Mleczko David Burbidge Nick Horspool 《Ocean Dynamics》2010,60(5):1115-1138
This paper presents a framework and data for spatially distributed assessment of tsunami inundation models. Our associated
validation test is based upon the 2004 Indian Ocean tsunami, which affords a uniquely large amount of observational data for
events of this kind. Specifically, we use eyewitness accounts to assess onshore flow depths and speeds as well as a detailed
inundation survey of Patong City, Thailand to compare modelled and observed inundation. Model predictions matched well the
detailed inundation survey as well as altimetry data from the JASON satellite, eyewitness accounts of wave front arrival times
and onshore flow speeds. Important buildings and other structures were incorporated into the underlying elevation model and
are shown to have a large influence on inundation extent. 相似文献
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97.
Ole H. Hald 《Geophysical Journal International》1980,62(1):41-48
Summary. It is shown that if Adams—Williamson's equation is used in the lower mantle and if the mass of the core and the density at the core—mantle boundary are given then the density, the rigidity and the incompressibility are uniquely determined throughout the mantle and in the crust by the velocities of the P - and S -waves and by one torsional spectrum. The velocity of the S -waves in the upper mantle and in the crust can be replaced by an additional torsional spectrum. 相似文献
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