Subsurface permeability contrasts control shallow groundwater flow dynamics in the critical zone of a glaciated, headwater catchment
Subsurface permeability contrasts control shallow groundwater flow dynamics in the critical zone of a glaciated, headwater catchment
复制标题
地下渗透率对比控制冰川源头流域关键区域的浅层地下水流动态
DOI：
10.1002/hyp.14672
复制
发表时间：
2022
影响因子：
3.2
通讯作者：
Schreiber, Madeline E.
中科院分区：
文献类型：
--
作者：
Benton, Joshua R.;McGuire, Kevin J.;Schreiber, Madeline E.
地下水流动方向的关键区域内的水源集水区往往被假定为模仿陆地表面地形梯度。然而，地下水水力梯度也受到地下渗透性差异的影响，这可能导致流动方向和幅度的变化。在这项研究中，我们调查了浅层地下水流方向，表面地形，低渗透性单位在哈伯德布鲁克实验森林（HBEF），NH的水源集水区的地下地形之间的关系。我们连续监测浅层地下水位的土壤在整个几个季节的井网（20威尔斯的0.18-1.1米深）在上山坡的流域3的HBEF。还监测了四口较深的威尔斯井的水位，这些井在C层冰川漂移内的2.4至6.9米深度进行了筛选。我们在整个井网中进行了段塞试验，以确定每口井周围材料的饱和导水率（Ksat）。结果表明，在较高的地下水位制度，地下水流方向模仿地表地形，但在较低的地下水位制度，流动方向可以偏离地表地形多达56度。在这些较低的地下水位条件下，地下水流动方向反而遵循C层顶部的地形。四分位距Ksat在C层内是两个数量级低于solum内。总的来说，我们的研究结果表明，陆地表面的地形和顶部的C地平线作为端成员定义的流动方向变化的上限和下限。这表明，地下水流方向的时间动态计算水文通量时，应考虑在临界区和径流产生的研究是由冰川漂移的源头集水区。
Groundwater flow direction within the critical zone of headwater catchments is often assumed to mimic land surface topographic gradients. However, groundwater hydraulic gradients are also influenced by subsurface permeability contrasts, which can result in variability in flow direction and magnitude. In this study, we investigated the relationship between shallow groundwater flow direction, surface topography, and the subsurface topography of low permeability units in a headwater catchment at the Hubbard Brook Experimental Forest (HBEF), NH. We continuously monitored shallow groundwater levels in the solum throughout several seasons in a well network (20 wells of 0.18–1.1 m depth) within the upper hillslopes of Watershed 3 of the HBEF. Water levels were also monitored in four deeper wells, screened from 2.4 to 6.9 m depth within glacial drift of the C horizon. We conducted slug tests across the well network to determine the saturated hydraulic conductivity (Ksat) of the materials surrounding each well. Results showed that under higher water table regimes, groundwater flow direction mimics surface topography, but under lower water table regimes, flow direction can deviate as much as 56 degrees from surface topography. Under these lower water table conditions, groundwater flow direction instead followed the topography of the top of the C horizon. The interquartile range ofKsatwithin the C horizon was two orders of magnitude lower than within the solum. Overall, our results suggest that the land surface topography and the top of the C horizon acted as end members defining the upper and lower bounds of flow direction variability. This suggests that temporal dynamics of groundwater flow direction should be considered when calculating hydrologic fluxes in critical zone and runoff generation studies of headwater catchments that are underlain by glacial drift.
登录
查看更多内容
影响因子：
2.6
作者：
J. Shanley;K. N. Hjerdt;J. McDonnell;C. Kendall
通讯作者：
C. Kendall
短暂到常年排水网络中地表水化学的精细尺度变化
影响因子：
3.2
作者：
M. Zimmer;S. Bailey;K. McGuire;T. Bullen
通讯作者：
T. Bullen
高地对中西部冰耕谷河岸带水文功能的控制 1
DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
P. Vidon;A. Smith
通讯作者：
A. Smith
变量“活跃”与“贡献”领域或时期：必要的区别
DOI：
--
发表时间：
2004
期刊：
影响因子：
--
作者：
B. Ambroise
通讯作者：
B. Ambroise
DEM 平滑和聚合对基于地形的流向和流域边界的影响
DOI：
--
发表时间：
2021
期刊：
影响因子：
--
作者：
J. Erdbrügger;I. Meerveld;K. Bishop;J. Seibert
通讯作者：
J. Seibert