Soil and humus form distribution in the ancient woodland of Haid Ege,Denmark     

Søren M. Kristiansen  Mogens H. Greve 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):27-36

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Constraining dark energy anisotropic stress     

David F. Mota  Jostein R. Kristiansen  Tomi Koivisto  Nicolaas E. Groeneboom 《Monthly notices of the Royal Astronomical Society》2007,382(2):793-800

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Summaries of presentations during the sixth Workshop of the International Association of Phytoplankton Ecology and Taxonomy,Mondsee, Austria, 15–25 September 1986     

H. R. Bürgi  Gerhild Deisinger  M. Dokulil  Barbara Hickel  Utsa Pollingher  Hedy Kling  Pertti Eloranta  Eugen Rott  Peter Pfister  Maria Moustaka  Ivan S. Heaney  Eugen Rott  A. E. Bailey-Watts  Jorgen Kristiansen  Asbjorn Skogstad 《Aquatic Sciences - Research Across Boundaries》1987,49(3):375-392

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Optimal selection of temperature areas by juvenile cod (Gadus morhua L.) in the Barents Sea modelled by dynamic optimisation     

Kristiansen  Tore S.; Michalsen  Kathrine; Jacobsen  Jan Arge; Huse  Irene 《ICES Journal of Marine Science》2001,58(1):172-182

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Increased colour and organic acid concentrations in Norwegian forest lakes and drinking water – a result of increased precipitation?     

Dag Hongve  Gunnhild Riise  Jan F. Kristiansen 《Aquatic Sciences - Research Across Boundaries》2004,66(2):231-238

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Problems in classification and identification of Synuraceae (Chrysophyceae)     

Jørgen Kristiansen 《Aquatic Sciences - Research Across Boundaries》1978,40(2):310-319

In the Synuraceae, the silica scales which cover the cell surface are of great taxonomic importance, although their delicate structure requires use of electron microscopy. Many species have been incompletely described by means of light microscopy, and there are serious difficulties in correlating them with species based on electron microscopy of the silica scales. The different types of variation in scale structure are described, and the variation range to be accepted within a species is discussed. However, as sexual reproduction is of rare occurrence in this family, the species concept must be highly arbitrary. It is reassuring then that many species based on scale ultrastructure also exhibit morphological and ecological characteristics. The advantages of scanning and transmission electron microscopy are emphasized for species identification and for detection of small forms with especially delicate scales.  相似文献   

Temporal behavior of manganese and iron in a sandy coastal sediment exposed to water column anoxia     

Erik?KristensenEmail author  Kim?Dyrberg?Kristiansen  Mikael?Hjorth?Jensen 《Estuaries and Coasts》2003,26(3):690-699

The influence of bottom water anoxia on manganese (Mn), iron (Fe), and sulfur (S) biogeochemistry was examined in defaunated sandy sediment from Kærby Fed, Denmark, under controlled laboratory incubations. The initial narrow peaks and steep gradients in solid Mn(IV) and Fe(III) as well as porewater Mn²⁺ and Fe²⁺ observed in the upper 2–5 cm of the sediment indicate rapid metal reduction-oxidation cycles under oxic conditions in the overlying water. The fe zones were generally displaced about 0.5 cm downward compared with the Mn zones due to differences in reactivity. Mn(IV) was reduced and gradually disappeared first (within 10 d) when the sediment was exposed to anoxia followed by reduction and disappearance of Fe(III) (day 7 to 18). The associated loss of Mn²⁺ to the overlying water was most rapid during the first 15 d, whereas the Fe²⁺ efflux initiated around day 10, and after a few days with modest rates the efflux peaked around day 20. A considerable portion of the total Mn (26%) and Fe (23%) inventory initially present in the sediment was lost by efflux after about 1 mo of anoxia. The ability of the sediment to retain upward diffusion of H₂S gradually disappeared in a temporal pattern closely related to the changes in pool size of the reactive Mn and Fe present. The total metal pool in Kærby Fed sediment prevented H₂S release to the overlying water for at least a month of anoxia. It is speculated that external supplies from the overlying water allows a rapid refuelling of surface Mn and Fe oxides in the field when oxic conditions returns between periods of anoxia.  相似文献