National Ecological Framework (6 of 23)

Land and water areas

The following attributes are included:

Area values (in hectares) for terrestrial ecozones, ecoprovinces, ecoregions and ecodistricts of Canada have been calculated using a Lambert Equal Area projection hydrologic map coverage created by the Canadian Soil Information System (CanSIS), Research Branch, Agriculture and Agri-Food Canada. This hydrographic coverage represents land, freshwater, and marine water within Canada. This coverage was merged with the ecozone, ecoprovince, ecoregion and ecodistrict map polygons to provide land and freshwater area values for each. The standard of what does constitute the official land and freshwater area of Canada is described in Sebert and Munro (1972). Land and freshwater bounded by coastline are included. Bodies of freshwater shared by Canada and the USA, such as the Great Lakes and the St. Lawrence River are included to the international boundary. The mouth of the St. Lawrence River to the western tip of Anticosti Island is considered freshwater, as well as Bras d’Or Lake on Cape Breton Island, Nova Scotia. Lake Melville in Labrador is considered marine water.

The hydrographic coverage, which was derived from 1:1,000,000 scale source data (National Topographic Series), includes only relatively large water bodies. Most lakes included in this hydrographic coverage are greater than 1 square kilometer in size. There are a significant number of smaller lakes not included in the calculation of land and freshwater in this database. This results in a slight over-estimate of land area, and a serious under-estimate of the water area. In comparison with previously calculated national total for land and freshwater (9,970,610 km²) in the Canada Yearbook (Statistics Canada 1994), the CanSIS estimates of land area (9,948,445 km²) account for 101.4% of all land area in Canada, and 80.4% of all freshwater area in Canada. Pro-rating of these areas will not account for local variation in the density and distribution of small water bodies, and is not an accurate reflection of their natural distribution.

This subject is treated more thoroughly in the CanSIS documentation for the SLC version 2.2 LAT table.  AREA_TOTAL, AREA_LAND and AREA_WATER fields were derived from the AREA_TOTAL, AREA_LAND and HYDRO_FRESH fields in the SLC v2.2 LAT table.  There are some errors due to rounding, so the totals for the country are not consistent between the estimates in the SLC LAT and the Ecological Framework tables.

References:

Sebert, R.J., and M.R. Munro. 1972. Dimensions and areas of maps of the National Topographic Systems of Canada. Technical Report No. 72-1, Surveys and Mapping Branch, Department of Energy , Mines and Resources, Ottawa, Ont.

Statistics Canada. 1994. Canada Yearbook 1994. Ministry of Industry, Science and Technology, Ottawa/Hull. pp. 707.