PRE-ADAPTATION OF ARCTIC PLANTS TO CLIMATE-CHANGE

Re-appraisal of high latitude ice cover during the Weichselian and the recent discovery of pre-Holocene plant communities in Novaya Zemlya a nd Northern Norway suggests that the contemporary Arctic flora may hav e had a longer time span in its occupation of high latitude sites than has hitherto been recognised. The present-day Arctic flora in some re gions may therefore have derived at least some of its genetic inherita nce from populations that survived in ice-free refugia in the high Arc tic polar deserts during the latter stages of the Weichselian glaciati on. Increasing evidence for sudden changes in climate at high latitude s in the past, suggests that Arctic vegetation would have been subject ed to rapid climatic warming if it had maintained a presence in these regions during the late Weichselian. A review of what is known about p lant survival in the high Arctic since pre-Holocene times, coupled wit h an examination of some of the physiological properties of modern pop ulations in these regions is presented in an attempt to ascertain if h igh Arctic plants possess mechanisms which facilitate their capacity t o respond either phenotypically or physiologically to climatic change.