Frequency domain water table fluctuations reveal impacts of intense rainfall and vadose zone thickness on groundwater recharge
نویسندگان
چکیده
Abstract. Groundwater recharge is difficult to estimate, especially in fractured aquifers, because of the spatial variability soil properties and lack data at basin scale. A relevant method, known as water table fluctuation (WTF) consists inferring directly from WTFs observed boreholes. However, WTF method neglects impact lateral groundwater redistribution aquifer; i.e., it assumes that all are attributable recharge. In this study, we developed approach frequency domain better consider flow, which quickly redistributes impulse mitigates link between First, calibrated a 1D analytical model estimate hydrodynamic parameters each borehole. These were defined recorded for several years, independently prescribed potential Second, models reversed analytically fluctuations (RFs) weekly monthly scales WTFs. Models tested on two twin sites with similar climate, aquifer land use but different hydrogeologic settings: one has been operated pumping site last 25 years (Ploemeur, France), while second not perturbed by (Guidel). Results confirm important role rainfall temporal distribution generating While contributes recharge, ratio minus evapotranspiration frequency-dependent, varying 20 %–30 % periods <10 d 30 %–50 scale reaching 75 seasonal timescales. We further show unsaturated zone thickness controls intensity timing RFs. Overall, assessment helps improve representation systems within hydrological models. spite heterogeneous nature controlling can be inferred time series, providing confidence deployed geological contexts where long-term records available.
منابع مشابه
Using Pedotransfer Functions in Vadose Zone Models for Estimating Groundwater Recharge in Semiarid Regions
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ژورنال
عنوان ژورنال: Hydrology and Earth System Sciences
سال: 2022
ISSN: ['1607-7938', '1027-5606']
DOI: https://doi.org/10.5194/hess-26-5697-2022