Because of the exceptional arrangement of the Sava River system, which comprehends three different climate regions, flood may occur at any time of the year. This volatility makes Lonjsko Polje an outstanding example of ecological processes caused by extreme and unpredictable oscillations of flood dynamics occurring in the central course of the Sava River. The great importance of the Central Sava Floodplains is related to the rarity of natural floodplain ecological systems in Europe, as a result of the drainage and regulation of the great rivers, particularly in their central courses.