Canada has defined a hierarchical classification of ecosystems. At a simple level there are 20 ecozones, fifteen terrestrial and five marine. An ecozone is an area of the earth’s surface that represents a large ecological zone and has characteristic landforms and climate. Each ecozone is distinguished from others by its unique mosaic of plants, wildlife, climate, landforms, and human activities. Ecozones are useful for general national reporting and for placing Canada’s ecosystem diversity in a North American or global context.