Abstract: To explore the correlation between karst groundwater level, precipitation, and Yellow River water level in Changqing District, Jinan City, we utilized long-term monitoring data of four karst groundwater levels in the Changqing-Xiaolipu hydrogeological unit from 2007 to 2019, alongside data on precipitation and Yellow River water level during the same period. By applying wavelet coherence and multiple wavelet coherence methods to analyze the data, we found the following results: 1) There are significant continuous or discontinuous one-year and half-year high-frequency main oscillation cycles in the dynamics of karst groundwater level. 2) The average wavelet coherence (AWC) and percent area of significant coherence (PASC) mean values between karst groundwater level and precipitation are 0.47 and 20.64%, respectively. The mean AWC and PASC between groundwater level and Yellow River water level are 0.42 and 13.00% respectively. Precipitation has a greater impact on groundwater level than the Yellow River water level. 3) The multiple wavelet coherence (MWC) between karst groundwater level and precipitation and Yellow River water level in Guangli Village of Xiaoli Town and Guide Town-Wenchang Street area increased by at least 5% compared to AWC, indicating that the karst groundwater level in this area is affected by both precipitation and Yellow River water level. These research findings are highly significant for further understanding the transformation relationship among precipitation, surface water, and groundwater. Furthermore, our findings could potentially benefit spring protection and water supply along the Yellow River in Jinan.

Key words: groundwater level, precipitation, Yellow River water level, multiple wavelet coherence