When one is asked to recall their fondest memory of a lake, the images can vary wildly. Memories of a mirror-like swamp, pink from the light of early morning are conjured. Some envision lunch in a quiet park alongside a manmade lake, ducks meandering about. Still others might envision summertime boating on a wind-swept lake so large that it might be a small ocean. This variation within our memories closely resembles the diverse nature of these bodies of water.
As it turns out, lakes in North America have a life of their own. Their origins have been categorized in 15 different ways by limnologists – scientists who study inland bodies of water. Lakes are sometimes not even lakes – their definition varies wildly, from one hectare to as much as forty hectares. That which we know as a pond, may be a lake by other definitions and vice versa.
Among these 15 categories are graduated levels of ecological support, referred to as a trophic system of classification. The levels define the life of the lake, its nutrient content and, ultimately, what it provides to us on the surface.