Water Infiltration into a Frozen Soil with Simultaneous Melting of the Frozen Layer

Abstract

Understanding water infiltration into frozen soil is important for preventing soil erosion and managing soil water and nutrients. In this study, we performed a column experiment on infiltration through frozen soil using a variably‐saturated silt loam. Three soil columns (7.8 cm i.d., 35 cm long), with three different initial soil water contents, were cooled from the top to form a frozen layer of the same thickness. The columns were instrumented with 34 thermocouples, seven time‐domain reflectometry (TDR) probes, and seven tensiometers. Water at a temperature of 3.5°C was applied to the top of the columns with a 15‐cm constant head. We monitored ice and liquid water contents, temperatures, and the position of the infiltration front. Three phases of infiltration were observed: (i) no infiltration at the beginning, (ii) slow infiltration as the infiltration front advanced through the frozen layer, and (iii) increased infiltration as the infiltration front advanced through the unfrozen soil below the frozen layer. The duration of each phase became longer with increasing initial soil water content as the infiltration rate of each phase decreased. The volumetric ice content and thickness of the frozen layer controlled the infiltration process. We use a capillary bundle model to characterize the hydraulic conductivity as a function of ice content during infiltration. Based on our experimental data and results, we mechanistically describe the water infiltration into frozen soil.

Analysis of spatial variability of near-surface soilmoisture to increase rainfall-runoff modellingaccuracy in SW Hungary

“…However, such models require accurate spatial parameterization of antecedent catchment states [6,7]. One crucial variable that contributes to the overall runoff/infiltration ratio during a rainfall event is soil moisture [8][9][10][11][12][13]. Soil moisture is also a key variable for the complex understanding of hydrological processes in the vadose zone.…”

“…Spatially and temporally varying soil moisture has been increasingly used as an input parameter to hydrological and meteorological models as soil moisture plays a crucial role in the surface runoff of water originating from heavy rainfalls [1]. The spatial distribution of soil moisture varies as a function of the spatial distribution of evapotranspiration and precipitation, ultimately influ-enced by topography, soil texture, and land use type [5][6][7][8]. Alternatives to collecting sufficient knowledge on its spatial distribution include high resolution in situ measurement and monitoring [17,18] or satellite remote sensing applications [19,20].…”

The hierarchy of controls on snowmelt-runoff generation over seasonally-frozen hillslopes

“…This might indicate that a longer winter period of deep soil freezing prevented the soil surface water content from dissipating vertically, thus retaining the soil moisture at the surface, and driving a high runoff ratio come the spring. It might also indicate that faster infiltration rates and reduced runoff ratios -when the wetting front reached the thawed layer below the frozen layer (Watanabe et al, 2012) -were not reached because the wetting front did not reach thawed soil when the soil was frozen to greater depths. The longer the soil was frozen and the deeper it was frozen, the stronger the soil moisture memory 20 was.…”

Winter hydrology and soil erosion processes in an agricultural catchment in Norway

“…Other more recent studies, e.g., Ban et al (2016), have shown that water flows much faster over a frozen slope than over a thawed slope. Watanabe et al (2013) found that the speed of snowmelt and/or rain infiltration into frozen soils is largely dependent on initial water content, frost depth and temperature of the soil. In addition, Yami et al (2012) showed that increasing soil moisture and finer soil structure advance the speed and depth of the freezing front.…”

“…Al-Houri et al, 2009;Iwata et al, 2011;Watanabe et al, 2013) and have attempted to link these to changes in soil structure. Until recently, the structural properties of soils had to be inferred from hydraulic measurements (Bodner et al, 2008) or destructive 2D visualisation methods (e.g.…”