Leelanau Conservancy Report of the Leelanau Watershed Council: Water Quality Monitoring Program (A Synthesis of Data from 1990 through 1995)

Abstract

Data collections from 1990 to the present have permitted "trophic status" determinations for the major lakes of Leelanau County (Leelanau, Glen, Little Traverse, Lime, and Cedar). Trophic status is a reflection of the nutritional state, or the ability of the lake to support plant growth. Lakes are classified as oligotrophic, mesotrophic, or eutrophic. Oligotrophic lakes have limited ability to sustain plant growth. (low production) and therefore are relatively free of nuisance aquatic plants, high in dissolved oxygen levels throughout the year, and usually contain fairly clear water. Eutrophic lakes support abundant plant growth (high production) and thus exhibit extensive weed populations, reduced oxygen levels (particularly during late summer), and murky water. Mesotrophic lakes fall in between. Because trophic status is a continuum rather than a yes or no condition, there is no single or absolute way to classifY a lake.