Karst
Karst is a term for a feature that forms on the landscape when water dissolves soluble bedrock such as limestone, marble, or dolomite. The resulting topography can include caves, sinkholes, springs, and disappearing streams, sometimes forming complex underground drainage systems.
The PAS Science Team is mapping significant karst areas in the NWT for several reasons. The substrate and chemical composition of karst landscapes creates unique habitats for aquatic and terrestrial species. Some species have adapted specifically to the karst environment and cannot survive anywhere else. Other species thrive there because of the relatively rich nutrient load in some karst soils. Physical characteristics of karst features provide important habitat for species such as bats, Dall’s sheep and other vertebrates and invertebrates that rely on caves for at least part of their lifecycle. The constant climatic conditions in subterranean karst provide an ideal environment for the preservation of fossils, making karst areas important to archaeologists and palaeontologists. The International Union for Conservation of Nature (IUCN) provides guidelines for management and protection of karst resources. Wherever possible, management should include the total karst catchment area. However, most of the karst systems in the NWT are remote and some are poorly studied. The most well-known karst systems are within the newly expanded Nahanni National Park Reserve.
To increase our knowledge of the location and significance of karst systems in the NWT, the PAS contracted Dr. Derek Ford to conduct a brief survey of known karst regions within the Sahtu Settlement Area in 2007 (report summary available here). Dr. Ford, Emeritus Professor of Geography and Geology at McMaster University, is a world leader in the study of karst landscapes. As a follow-up, the PAS contracted Dr. Ford in 2008 to conduct a survey of air photos of the NWT to map visible karst features for the entire NWT. This report will be available in late 2009.
