Long-time monitoring and analysis of lake changes with satellite technology

Water is the source of life, the essence of production and the foundation of ecology. Water resources is one of important elements of natural resources and satellite technology is an irreplaceable method of high-quality water resources monitoring. With Chinese Ziyuan and Gaofen serial satellites as well as the Landsat satellites, a 1970-2022 long-time monitoring and analysis is performed on 132 major lakes which areas are above 1km² in Anhui province, China. This paper use the OTSU threshold method as well as best-fit buffer area algorithms to preform the lake area extraction. Results reveals that since 1970, the total water surface area of the 132 major lakes in Anhui Province has shown a fluctuating trend. The smallest total lake area was 3650.33km² in 1970. Due to severe torrential rains and flooding in the Yangtze and Huaihe River basins in July 2020, the total lake area reached its maximum of 4840.60km² in 2020, an increase of 1190.27km² or 32.61% compared to 1970. The lake long-time monitoring results will be beneficial to the related research on water resources investigation, monitoring and evaluation in Anhui province, China.