Note on eco-classification systems
Authors: Kettles I M 
Published: March 2017

The history of the development and evolution of ecological land classifications that encompass the Canada landmass is outlined in the following:
Marshall and P.H. Schut (1999). A national ecological framework for Canada - overview; on-line at http://sis.agr. gc.ca/cansis/nsdb/ecostrat/intro.html [accessed March 9, 2010].
In the late 1960s there was recognition of the need for a nation-wide ecological framework to provide standardized, multi-scale geographical reporting and monitoring units. One aim was to think, act, and plan based on ecosystems rather than have emphasis on individual elements. Ecological land
classification incorporates all major components of ecosystems: air, water, land, and biota, including humans. It is based on a hierarchy with ecosystems nested within ecosystems. In 1976 the Canada Committee on Ecological Land Classification was created to develop (1) a uniform national ecological
approach to terrestrial ecosystem classification and mapping and (2) to encourage the use of the ecological approach to sustainable resource management and planning. The first version had 7 levels of generalization and from the start there was recognition that the spatial units needed revisions. In
1991 a collaborative project was undertaken after the first State of Environment report for Canada published in 1986 by some federal, provincial and territorial governments. The objective was to revise the previous work and establish a common ecological framework for Canada. The working group
focused on 3 levels - ecozones, ecoregions, and ecodistricts - and the result was a national report entitled "A National Ecological ramework for Canada" released in 1996. The report described the methodology used to construct the ecological framework maps, the concepts of the hierarchical levels of
generalization, narrative descriptions of each ecozone and ecoregion and their linkages to various data sources. The State of the Environment Reporting spatial framework is maintained by the CanSIS group at Agriculture and Agri-Food Canada. Since 1996, groups in British Columbia, Saskatchewan,
Manitoba and Nova Scotia have provided more in-depth descriptions of the ecological units in these provinces. The NAFTA Commission for Environmental Cooperation (CEC) made some modifications to the State of the Environment Reporting spatial framework for Canada to provide an integrated perspective
for all of North America. Results were released in 1997 as "Ecological Regions of North America - Towards a Common Perspective". When the North America perspective was being developed, an ecoprovince level of generalization, between ecozone and ecoregion, was compiled for the Canadian framework. For
Canada, the CANSIS database consists of 15 ecozones, 53 ecoprovinces, 194 ecoregions, and 1021 ecodistricts. For North America, the Commission for Environmental Cooperation (CEC) database has the following number of units: Level 1- 15; Level 2 - 52; Level 3 - 182, and Level 4 - not as yet completed.
Geochemical data sets that are geo-referenced can be "cookie cut" using any eco-classification system and GIS. The different systems of reporting are similar but not identical and the one being used should be clearly stated. The CanSIS system is widely used in Canada and is recommended for national
and regional reporting. The scale or level of data used depends on the project purpose and the amount of data available. If using the more detailed scales of eco-classification information, it is necessary to have sufficient data points within the individual ecosystem polygons to ensure the validity
of statistical comparisons.