Analysis of information sources in references of the Wikipedia article "Ecoregion" in English language version.
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: CS1 maint: multiple names: authors list (link)North America has been divided into: 15 broad, level I ecological regions; 50 level II ecological regions intended to provide a more detailed description of the large ecological areas nested within the level I regions; and 182 Level III ecoregions, which are smaller ecological areas nested within level II regions.
Ecoregions are areas where ecosystems (and the type, quality, and quantity of environmental resources) are generally similar.
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