Groundwater is a vital water resource in arid and semi-arid areas. Diurnal groundwater table fluctuations are widely used to quantify rainfall recharge and groundwater evapotranspiration (ETg). To assess groundwater resources for sustainable use, groundwater recharge and ET_g were estimated using the diurnal water table fluctuations at three sites along a section with different depths to water table (DWT) within a wetland of the Mukai Lake in the Ordos Plateau, Northwest China. The water table level was monitored at an hourly resolution using a Keller DCX-22A data logger that measured both the total pressure and barometric pressure, so that the effect of barometric pressure could be removed. At this study site, a rapid water table response to rainfall was observed in two shallow wells (i.e., Obs1 and Obs2), at which diurnal water table fluctuations were also observed over the study period during rainless days, indicating that the main factors influencing water table variation are rainfall and ET_g. However, at the deep-water table site (Obs3), the groundwater level only reacted to the heaviest rainfalls and showed no diurnal variations. Groundwater recharge and ET_g were quantified for the entire hydrological year (June 2017–June 2018) using the water table fluctuation method and the Loheide method, respectively, with depth-dependent specific yields. The results show that the total annual groundwater recharge was approximately 207 mm, accounting for 52% of rainfall at Obs1, while groundwater recharge was approximately 250 and 21 mm at Obs2 and Obs3, accounting for 63% and 5% of rainfall, respectively. In addition, the rates of groundwater recharge were mainly determined by rainfall intensity and DWT. The daily mean ET_g at Obs1 and Obs2 over the study period was 4.3 and 2.5 mm, respectively, and the main determining factors were DWT and net radiation.

地下水是干旱和半干旱地区的重要水资源。地下水的昼夜波动被广泛用于量化降雨补给和地下水蒸散量（ETg）。评估地下水资源的可持续利用，地下水补给和ET _g利用西北地区鄂尔多斯高原穆凯湖湿地内不同深度的地下水位（DWT）的三个位置的日地下水位波动来估算。使用Keller DCX-22A数据记录器以每小时的分辨率监测地下水位，该数据记录器测量了总压力和大气压力，因此可以消除大气压力的影响。在该研究地点，在两个浅井（Obs1和Obs2）中观察到地下水位对降雨的快速响应，在无雨天的研究期内，还观察到了日地下水位的波动，这表明影响水的主要因素表格变化是降雨量和ET _g。然而，在深水位（Obs3），地下水位仅对最大的降雨有反应，并且没有昼夜变化。使用水深波动法和洛希德法分别对整个水文年（2017年6月至2018年6月）的地下水补给量和ET _g进行定量，并随深度而定。结果表明，每年的地下水补给总量约为207 mm，占Obs1降雨量的52％，而Obs2和Obs3的地下水补给约为250 mm和21 mm，分别占降雨量的63％和5％。此外，地下水补给率主要取决于降雨强度和DWT。日均ET _g 在研究期间，Obs1和Obs2的辐射分别为4.3 mm和2.5 mm，主要决定因素是DWT和净辐射。