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Der Säurestoffwechsel von Welwitschia mirabilis Hook. Fil. Am Natürlichen Standort in der Namib Wüste

  • E.-D. Schulze
  • H. Ziegler
  • W. Stichler
Chapter

Abstract

Within the area of its natural distribution in Southwest Africa, Welwitschia mirabilis has a higher ∂13 C value than C3 plants and a lower ∂13 C value than C 4 plants occuring in the same habitat. This indicates that Welwitschia m. fixes part of its carbon by crassulacean acid metabolism (CAM) when growing in its natural habitat. Measurements of ∂13 C values show the proportion of carbon fixed by CAM to be higher in the savanna zone than in the subtropical grassland zone. Even higher ∂13 C values were measured on Welwitschia m. in the coastal desert. There was no correlation between ∂13 C values and the ash content of plant material and with water stress indicating that these factors were not responsible for the observed shift in carbon metabolism. It was concluded, after an analysis of temperature conditions, that cool night temperatures were possibly responsible for promoting a greater portion of CAM in Welwitschia m. in the coastal desert as compared with savanna and subtropical grassland zones.

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Copyright information

© Springer Science+Business Media Dordrecht 1976

Authors and Affiliations

  • E.-D. Schulze
    • 1
  • H. Ziegler
    • 2
  • W. Stichler
    • 3
  1. 1.Lehrstuhl PflanzenökologieBayreuthDeutschland
  2. 2.Institut für Botanik und MikrobiologieTU MünchenMünchen 2Deutschland
  3. 3.Institut für Radiohydrometrie, GSFNeuherbergDeutschland

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