VEGETATION AND ENVIRONMENT OF THE CANADIAN HIGH ARCTIC WITH SPECIAL REFERENCE TO CORNWALLIS ISLAND (Twelfth Symposium on Polar Biology)

Vegetation of Cornwallis Island, Canada, was studied. A total of fifty-one sample plots were established to represent the vegetation of the high arctic. The plots were assembled and classified according to the phytosociological procedures. Seven vegetation types each of which may be comparable to plant association (sensu KRAJINA) were distinguished, namely, 1. Saxifraga caespitosa-Poa arcticaiype, 2. Saxifraga oppositifolia-Draba bellii type, 3. Saxifraga oppositifolia-Festuca baffinensis type, 4. Saxifraga oppositifolia-Dryas integrifolia type, 5. Saxifraga oppositifolia-Salix arctica type, 6. Dupontia fisheri-Alopecurus alpinus type, and 7. Carex stans type. Edaphic conditions in terms of soil moisture regime and coarseness of substrates were assessed and correlated with the vegetation types. Moisture availability seemed to have been an important factor to regulate the vegetation development. When habitat was moist enough, vegetation obviously exhibited a high plant coverage and species diversity. Nutrient supply seemed to be also another important factor as lush growth of vegetation was recognized in nutritionally enriched sites. It was concluded that, even under a frigid climate of the arctic environment, the desolate landscape of polar desert was in fact substantiated by an insufficient supply of moisture and nutrients