A method to assess the alteration of water-level-fluctuation patterns in lakes.

Abstract: The alteration of natural water-level-fluctuation patterns is a key cause of ecological degradation in lake ecosystems. In this research a method is developed to measure the alteration degree of natural water-level-fluctuation patterns in lakes. Utilizing this method, a series of indicators are developed that can reflect the pattern of water level fluctuation. The dissimilarity between the pre- and post-impacted frequency histograms for each indicator is evaluated using a metric called the Earth Mover''s Distance. A case study of Baiyangdian Lake shows the water-level-fluctuation pattern alteration degree calculated by the new method is consistent with the ecological degradation degree, indicating the new method''s ability to reflect the ecological degradation degree based only on hydrological data [Copyright &y& Elsevier]