British Columbia: Ecosystem Classification System
B.C. is the most ecologically diverse province in Canada. There have been attempts to identify, classify, and map the extraordinary diversity of B.C.’s ecosystems. Dr. V.J Krajina, a plant ecologist in the Department of Botany at the University of British Columbia, developed a system to classify the ecosystems or “biogeoclimatic zones” by their climates and their dominant vegetation. The biogeoclimatic ecosystem classification (BEC) system was adopted by the provincial Ministry of Forests in the 1970s and is still used today to classify and manage ecosystems on a site-specific basis.
An ecosystem can be defined as the dynamic interactions between organisms (i.e., plants, animals and microorganisms) and their environment working together as a functional unit. In BEC, the definition of an ecosystem is more specific and can be thought of as the interactions between climate and soil that determine the vegetation in a particular area. Each biogeoclimatic zone in B.C. incorporates three levels of classification as the name implies. “Bio” refers to the biological characteristics of the ecosystem. “Geo” refers to the soil and geology of the area. And, “climatic” refers to the climate of the zone. These three levels together help predict which plants will grow in a certain area, and thereby the biogeoclimatic zone is classified by the dominant vegetation type.
There are fourteen major zones in the province: Coastal Western Hemlock, Interior Cedar Hemlock, Coastal Douglas-fir, Interior Douglas-fir, Ponderosa Pine, Bunchgrass, Montane Spruce, Engelmann Spruce, Subalpine Fir, Mountain Hemlock, Sub-boreal Spruce, Sub-boreal Pine, Spruce, Boreal White and Black Spruce, Spruce-Willow-Birch, and Alpine Tundra. These zones can be subdivided into subzones and divided further into subzone variants according to vegetation, climate, and elevation.
It is important to identify, classify and map the immense biodiversity in B.C. for a number of reasons. It helps foresters, ecologists, and biologists manage B.C. forests and grasslands by predicting the potential plant communities and species composition. The plant communities in turn predict the wildlife species that may inhabit the zone. The BEC system is also an important way to monitor changes in the biodiversity within and among the ecosystems. This system of classification provides us with a detailed method for mapping and describing the ecology of B.C.
References:
Cannings, R. and S. Cannings. 2004. British Columbia A Natural History. Vancouver:
Greystone Books. pp. 92–93.
Medinger, D. and J. Pojar eds. 1991. Ecosystems of British Columbia. British Columbia
Ministry of Forests. Victoria: Crown Publications. pp. 1–5.
Marcoux, D. Biogeoclimatic Ecosystem Classification. Selkirk College. http://selkirk.ca/rr/bec/zones