Hydrological rhythm refers to the periodicity of the lake's water regime with changes in rhythm. The generalized hydrological rhythm includes day and night, monthly transport, seasonal and interannual rhythms. Under normal circumstances, the average water level of the lake for many years is stable due to factors such as the basin climate and underlying surface. The value tends to be stable, that is, the normal average annual water level of the lake. Therefore, the interannual rhythm of the lake is characterized by the mutation-driven by disturbance factors and the stability of the stage after adaptation to disturbance, and there is no gradual trend. Hydrological rhythm refers specifically to the monthly rhythm and seasonal rhythm. Based on the above definitions, the following are related to narrow hydrological rhythms:. ['Poyang Lake is affected by the continuous decrease of rainfall and the decrease of incoming water, and the water surface area continues to shrink.', 'The historical average annual water temperature of Hongze Lake is 16.3 㠃. The highest water temperature is in September and the lowest water temperature is in January.', 'The annual rainfall of Dongting Lake was 1,560 mm, of which about half of the precipitation was from April to June.', 'The annual average temperature of the Chaohu Basin is stable between 15 and 16 㠃. There is a frost-free period of more than 200 days.']