Characteristics of lake evolution in the Eastern Plain Region under the dual impacts of human activities and climate change—a case study of Wabu Lake

Objective The eastern plain region is the most important freshwater lakes concentrated distribution area in China, but also economically developed, densely populated areas, lakes by human activities have the strongest impact, coupled with recent years in the middle and lower reaches of the Yangtze River frequent extreme weather, the evolution of the lakes show complexity. Methods Based on 10 periods of Landsat and high-fraction imagery data in every five-year period from 2002 to 2022, Wabu Lake was selected as a typical lake, and visual interpretation was used to extract the vector data during the dry water period (November-April) and the abundant water period (May-October), to analyse the morphology changes by using the shoreline index, and to investigate the factors affecting the evolution of Wabu Lake by combining with the correlation coefficients.Results In the past 20 years, the area of Wabu Lake increased by 11.60 km2 and the shoreline increased by 23.37 km during the dry period, and the maximum values of area and shoreline occurred in July 2007. Due to extreme flooding, the shoreline of Wabu Lake was the most developed and the fractal dimension was the largest in 2007, while the morphology of the lake became more and more complex during the dry period of Wabu Lake in the past 20 years, corresponding to more and more frequent circulation of littoral materials. Conclusions In general, the area and circumference of Wabu Lake have gradually increased, while anthropogenic activities are the dominant factor causing the evolution of Wabu Lake, and heavy precipitation caused by extreme weather is the main reason for the evolution of Wabu Lake during the abundant water period in 2003 and 2007.