Lake Water Quality 2006 Report - Lakefield Herald

Epiphytes – Algae that cling to and grow on submerged aquatic vegetation.Eutrophication – The aging of a body of water as it increases in dissolved nutrientslike phosphorus and declines in oxygen. This is often a natural process that can beaccelerated by shoreline development and other human activities.Evapotranspiration – The part of the hydrologic cycle in which water vapour movesfrom the Earth to the atmosphere, evaporating off surface water and rising fromtrees and other plants through pores in their leaves (transpiration).Flushing period – The average amount of time that water remains in a lake beforeflowing out.Freshet – Meltwater and rainwater that pours into watercourses in the spring.Glacial till – Geological deposit of unsorted sand, clay and rocks carried along by aglacier and dumped when it melts.Lake morphology – Factors relating to the physical structure of a lake, such as depth,shape, amount of shoreline, etc.Lentic systems – Still-water environments such as ponds and lakes.Macrophyte – A plant, generally aquatic, that is visible to the eye, i.e. not microscopic.Marl lake – These lakes receive drainage from limestone dominated watersheds.Acidic rainfall dissolves the limestone as it percolates through the rocks or soil.When the high-calcium water in the lake warms in the summer, the carbon dioxideformingcarbonic acid is reduced and the dissolved limestone precipitates out. Thislimestone (calcium carbonate) that collects on the lake bottom is called marl.Metaphyton – Floating algae that can get tangled up in beds of macrophytes andfloating debris.Paleozoic – Era of geologic time from about 540 to 250 million years ago in whichmajor life forms evolved, such as invertebrates, trilobites, fish, reptiles and land89