Diatoms as indicators of water level change in freshwater lakes

Water level changes result from a variety of geological, biological or climatic processes. Many of these changes occur over long periods of time; however, some may be rapid or result from catastrophic events. In glaciated regions, water level changes are influenced by the geological process of isostatic rebound. As the weight of glacial ice is removed from the Earth's surface, depressed surfaces adjust upward, while adjacent areas may subside (i.e., Larsen, 1987). Lakes are often formed as embayments become isolated from larger water bodies, and existing lakes can reinvade subsiding regions. Differential rates of rebound within large lake basins may affect drainage patterns and water levels. Transport of sediments across river mouths or embayments can also create lakes and increase water levels.