Abstract:

We carried out long-term water level monitoring of a well in the quaternary sandy aquifer of Maowusu Sandy Land in China, selected four pumping processes of this well at different times in 1 year, analyzed the differences in the pumping and depth reduction processes, and systematically analyzed the possible factors of such differences. On the basis of multiple influencing factors, the main controlling factors of the differences in the depth of sandy diving aquifer were clarified, and the hydrogeological characteristics of the fourth-series diving aquifer in the Hailiutu River Basin at different times were effectively revealed. We introduced the Bland-Altman method to this study for the first time and used it to quantitatively analyze the difference between the pumping depth reduction processes. Moreover, we applied the traditional wiring method to solve hydrogeological parameters and the water level restoration method to solve the hydrogeological parameters of the quaternary aquifer for differentiation. Finally, this paper analyzed the main reasons for differences in the pumping depth by evaluating the aquifer thickness, hydraulic slope, groundwater reserves, and precipitation recharge at the watershed scale. Results showed that the variation range of water conductivity coefficient of the quaternary phreatic aquifer in Hailiutu River Basin of Mu Us Sandy Land is 3.00-4.85 m²·h^-1 and the infiltration and replenishment of the vadose belt by precipitation before pumping is the main controlling factor for the differences in pumping depth.

Key words: pumping depth, difference, phreatic aquifer, hydrogeological parameter