Remote Monitoring of Freeze–Thaw Transitions in Arctic Soils Using the Complex Resistivity Method
Remote Monitoring of Freeze–Thaw Transitions in Arctic Soils Using the Complex Resistivity Method
复制标题
使用复电阻率法远程监测北极土壤冻融转变
DOI：
10.2136/vzj2012.0062
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发表时间：
2013
影响因子：
2.8
通讯作者：
S. Wullschleger
中科院分区：
文献类型：
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作者：
Yuxin Wu;S. Hubbard;C. Ulrich;S. Wullschleger
我们监测冻融转变的能力对于发展高纬度环境中地球化学转变和碳动力学的预测性理解至关重要。在这项研究中，我们进行了实验室柱实验，以探讨潜在的复电阻率方法监测冻融转变的北极多年冻土。实验样品从位于阿拉斯加州巴罗的巴罗环境观测站（BEO）的Gelisol土壤的上部活性层收集。通过将土柱暴露于4 ° C和−20°C的受控温度环境中诱导冻融转变。复电阻率和温度测量值定期收集在冻融过渡期间使用电极和温度传感器安装沿着列。在实验过程中，当温度在−20 ° C和0°C之间升高或降低时，观察到电阻率变化超过两个数量级。在0°C附近的等温解冻或冷冻过程中也观察到较小的电阻率变化。单频电相位响应和虚电导率在1赫兹被发现是专门相关的未冻结的水在土壤基质中，这表明这些地球物理属性可以被用来作为一个代理监测的发病和进展的冻融过渡。光谱电响应和拟合的Cole-Cole参数包含有关土壤粒度分布影响的冻融过渡的额外信息。具体而言，观察到的光谱响应的较低的频率的偏移，观察在等温解冻过程中，我们解释为由于顺序解冻，首先从细颗粒，然后粗颗粒内的土壤基质。我们的研究表明，潜在的复电阻率方法在北极土壤冻融过渡的远程监测。虽然是在实验室规模进行的，但这项研究为探索复电阻率信号的潜力提供了基础，用于监测现场相关尺度上冻融过渡的时空变化。
Our ability to monitor freeze–thaw transitions is critical to developing a predictive understanding of biogeochemical transitions and carbon dynamics in high latitude environments. In this study, we conducted laboratory column experiments to explore the potential of the complex resistivity method for monitoring the freeze–thaw transitions of the arctic permafrost soils. Samples for the experiment were collected from the upper active layer of Gelisol soils at the Barrow Environmental Observatory (BEO) in Barrow, Alaska. Freeze–thaw transitions were induced through exposing the soil column to controlled temperature environments at 4 and −20°C. Complex resistivity and temperature measurements were collected regularly during the freeze–thaw transitions using electrodes and temperature sensors installed along the column. During the experiments, over two orders of magnitude of resistivity variations were observed when the temperature was increased or decreased between −20 and 0°C. Smaller resistivity variations were also observed during the isothermal thawing or freezing processes that occurred near 0°C. Single frequency electrical phase response and imaginary conductivity at 1 Hz were found to be exclusively related to the unfrozen water in the soil matrix, suggesting that these geophysical attributes can be used as a proxy for the monitoring of the onset and progression of the freeze–thaw transitions. Spectral electrical responses and fitted Cole–Cole parameters contained additional information about the freeze–thaw transition affected by the soil grain size distribution. Specifically, a shift of the observed spectral response to lower frequency was observed during the isothermal thawing process, which we interpret to be due to sequential thawing, first from fine particles and then to coarse particles within the soil matrix. Our study demonstrates the potential of the complex resistivity method for remote monitoring of freeze–thaw transitions in arctic soils. Although conducted at the laboratory scale, this study provides the foundation for exploring the potential of the complex resistivity signals for monitoring spatiotemporal variations of freeze–thaw transitions over field‐relevant scales.
砂岩光谱诱导偏振响应对温度的依赖性及其与渗透率估算的相关性
影响因子：
--
作者：
Zisser N;Kemna A.;Nover G.
通讯作者：
Nover G.
影响因子：
3.9
作者：
Hilbich, C.;Hauck, C.;Maeusbacher, R.
通讯作者：
Maeusbacher, R.