Abstract:

Affected by natural factors and human activities, extreme hydrological conditions have emerged in Poyang Lake in recent years. During the flood season of 2020, Poyang Lake’s highest water level broke historical records. Conversely, in 2022, Poyang Lake experienced an unusual “drought during flood season”, with multiple stations registering their lowest water levels ever. These extreme hydrological conditions have significantly impacted flood control and drought relief in the lake area and even the downstream regions of the Yangtze River. This study summarizes and analyzes extreme flood and drought events based on hydrological and atmospheric circulation data from the Poyang Lake basin and operational records of the Three Gorges Project. The primary cause of these extreme hydrological conditions in Poyang Lake is the subtropical anticyclone, which, under the influence of El Ni \dot{n}o and La Ni \dot{n}a phenomena, affects inflow, outflow, and rainfall within the lake basin. Additionally, the regulation of main and branch reservoirs in the upper reaches of the Yangtze River also influences these extreme flood and drought hydrological situations. In response to these findings and the practical needs of Poyang Lake, this paper proposes corresponding countermeasures and recommendations to enhance the flood and drought disaster resilience of the Poyang Lake basin.

Key words: climate change, extreme flood and drought hydrological regime, hydrological countermeasures, Poyang Lake