Specific yield is a key parameter for the sustainable management of unconfined aquifers, since it relates water-table fluctuations to aquifer storage-changes and thus impacts water supply. However, estimating specific yield is still a challenge due to theoretical and methodological limitations. Water-storage changes in the aquifer and in the overlying unsaturated soil profile cause local changes in gravity that can be recorded by high-precision superconducting gravimeters. In this work, a novel methodology to estimate specific yield from superconducting gravimeter data is presented. The proposed methodology is based on a hydrogravimetric model that estimates the gravity response due to the loss and gain of water mass in the soil profile using rainfall, water-table and air-temperature data. The model is applied to a study site of the Pampeano aquifer in Argentina where a continuous 1-year record of superconducting gravimeter measurements is available. The specific yield value obtained using this methodology is 0.11 ± 0.039, which is validated by means of a long-term pumping test performed at the study site. The proposed method constitutes a promising alternative to the available tools for estimating specific yield, by taking advantage of superconducting gravity data.

比产量是无限制含水层可持续管理的关键参数，因为它将地下水位波动与含水层的储水变化联系起来，从而影响供水。然而，由于理论和方法上的局限性，估计比产率仍然是一个挑战。含水层和上覆的非饱和土壤剖面中的蓄水变化会引起重力的局部变化，这种变化可以通过高精度超导重力仪记录下来。在这项工作中，提出了一种从超导重力仪数据估算比产率的新颖方法。所提出的方法基于水力重力模型，该模型使用降雨，水位和气温数据估算由于土壤剖面中水量的损失和增加而引起的重力响应。该模型已应用于阿根廷潘帕诺（Pampeano）含水层的研究地点，在那里可以连续获得1年的超导重力仪测量记录。使用这种方法获得的比产率值是0.11±0.039，通过在研究地点进行的长期抽水试验进行了验证。通过利用超导重力数据，所提出的方法构成了用于估算比产率的可用工具的有前途的替代方法。