Floristic richness of three perhumid New Zealand alpine plant communities in comparison with other regions

Abstract Results are presented on vascular species richness in three representative alpine plant communities at 1040–1410 m on Mt Burns in the perhumid Fiordland region, a hotspot of alpine plant diversity, in south‐western South Island, New Zealand. Overall species richness was not dissimilar between the three communities in any of the eight plot sizes (mean values of 20.8–24.4 species in the largest plots of 100 m²), even though coefficients of floristic similarity were small (17.9; 23.5) between both low‐alpine communities (snow tussock‐shrubland and snow tussock grassland) and the high‐alpine cushion fellfield. Vascular species richness was generally similar to that in the few other oceanic New Zealand alpine communities for which data are available. The decline in richness from the low‐alpine to high‐alpine zones, revealed in more comprehensive records from two other regions with generally similar oceanic environments, was not recorded, indeed was reversed, on Mt Burns. Whether the recognized biodiversity hotspot of Fiordland has a generally richer high‐alpine flora than other regions in New Zealand needs further examination. The general pattern of alpine floristic richness in relation to elevation, in New Zealand, also prevails in most alpine regions abroad, usually under much more extreme continental environments. This pattern is usually ascribed to the associated decrease in temperature. Both the small size of the land mass and/or associated environmental conditions may be implicated but clarification awaits further data, preferably collected with standardized procedures.     

Synthesis of Cell Coat in Normal and Transformed Cells

THE surface of transformed cells has been a focus of considerable attention recently because some of the properties which distinguish these cells from their precursors, such as decreased cell adhesiveness, altered cell orientation and loss of contact and density dependent inhibition^1–3, may relate to changes on their surface. A common feature of vertebrate cells is the cell coat, a glycoprotein structure surrounding the plasma membrane⁴. Electron microscopy has revealed that transformed cells have a thicker coat than normal cells⁵ and we have now found that coat synthesis in cells transformed by an oncogenic DNA virus and in cells transformed by a chemical carcinogen occurs faster than in normal controls whereas only in the virus-transformed cells is the coat significantly thicker.