An alternative to traditional seepage meters: Dye displacement
An alternative to traditional seepage meters: Dye displacement
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传统渗漏计的替代方案：染料置换
DOI：
10.1029/2010wr009113
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发表时间：
2011
影响因子：
5.4
通讯作者：
P. Berg
中科院分区：
文献类型：
--
作者：
D. Koopmans;P. Berg
开发了一种新的渗透计设计，该设计增加了对驱动海底地下水排放的小水力梯度的灵敏度，作为传统渗透计的廉价替代品。新的设计用开口管取代了渗漏计袋，通过开口管注入染料的位移是一种高度可重复的排放测量。实验室测量、渗透计周围地下水流的详细数学模型以及袋式和染料置换式渗透计的平行现场测试表明，新设计可以提高海底地下水流量测量的精度和时间分辨率。在平行的现场测试中，地下水排放到直径为15 cm的袋式渗透仪的排放量是相邻直径为15 cm的染料置换渗透仪的排放量的一半。模型结果证实，在普通现场条件下，在部署直径为57 cm的渗透计时，可能会出现类似的差异，这是由袋式渗透计周围的地下水分流引起的。直径为15 cm的染料置换式渗透仪的第二次现场部署显示，在高潮时，盐水流入桑迪沉积物，在低潮时，盐水的排放率很高，这与其他研究中使用昂贵得多的开放流路自动渗透仪进行的观察结果相似。
A new seepage meter design that increases sensitivity to the small hydraulic gradients that drive submarine groundwater discharge was developed as an inexpensive alternative to traditional seepage meters. The new design replaces seepage meter bags with open‐ended tubing through which the displacement of injected dye is a highly reproducible measure of discharge. Laboratory measurements, detailed mathematical modeling of groundwater flow around seepage meters, and parallel field tests of bag and dye displacement seepage meters demonstrated that the new design can improve the precision and temporal resolution of submarine groundwater discharge measurement. In parallel field tests, groundwater discharge to 15 cm diameter, bag‐equipped seepage meters was half of the discharge to adjacent 15 cm diameter dye displacement seepage meters. Model results confirm that similar discrepancies, caused by groundwater diversion around bag‐equipped seepage meters, may occur during the deployment of 57 cm diameter seepage meters in common field conditions. A second field deployment of 15 cm diameter dye displacement seepage meters showed saline inflow into sandy sediments at high tide and a high rate of discharge at low tide, similar to observations made with far more expensive, open flow path automated seepage meters in other studies.