cold zone ecosystem(The interacting system of a biological community and its non-living environmental surroundings located in climatic regions where the air temperature is below 10° Celsius for eight to eleven months of the year)
coliform bacterium(A group of bacteria that are normally abundant in the intestinal tracts of human and other warm-blooded animals and are used as indicators (being measured as the number of individuals found per millilitre of water) when testing the sanitary quality of water)