Distribution of Thermophilic Bacteria in Arctic and Subarctic Habitats

Abstract

Terrestrial and aquatic habitats of North American and the European Arctic and Subarctic were sampled for the presence of thermophilic, mesophilic, and psychrophilic bacteria. Thirteen geographic regions of Alaska, one in northern Canada, and seven in Norway were studied. In general, the number of thermophiles was low, and in many cases they were completely absent, particularly in samples of fresh water. They were found in highest numbers in materials which had been contaminated by human or animal sewage; in water, from hot springs and adjacent soils; in soils, particularly in Norway, which had been cultivated without the addition of organic manures; in soils which had been disturbed; and for unknown reasons they were present naturally in highest numbers in certain soils of northern Canada, where there was, in most cases, no known history of sewage contamination or cultivation. Although warmblooded animals may be the original source of some of these microorganisms, there is strong evidence to suggest that some strains occur naturally in waters and soils of these regions.