Annual Lake Cycles can also affect the nutrient movement in a lake, and increase or decrease the possibility of eutrophication.
	Threemile Pond is dimictic, which means that the water in the lake turns over twice every year: once in the spring and again in the fall.
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	¥Lake water turnover begins with temperature variations, which create different water densities, and consequently a stratified water column
	Based on temperature and plant and animal life, different layers have varying amounts of oxygen.
	Turnover occurs in the spring and fall as water temperatures and densities change, which oxygenates the lake.
	However, When a lake is stratified for an extended period of time, such as in the late summer, oxygen levels become depleted, particularly in the deepest layer (called the hypolimnion) causing anoxic conditions.
	Under anoxic conditions, phosphorus is released from the sediment into the water column. This nutrient feeds algal growth, which can cause eutrophication.