TITLE:
Characterizing Subzero-Temperature Thermal Properties of Seasonally Frozen Soil in Alpine Forest in the Western Sichuan Province, China
AUTHORS:
Hui Sun, Shuai Liu, Jihong Qin
KEYWORDS:
Alpine Soil, Seasonally Frozen Soil, Thermal Properties, Qinghai-Tibetan Plateau
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.8 No.5,
May
20,
2016
ABSTRACT: Seasonally frozen soil in alpine and subalpine zones in the mountains of
Qinghai-Tibetan Plateau is particularly sensitive to global climate change.
Therefore, a better understanding of the thermal properties of frozen soil is crucial for predicting the
responses of frozen soils to soil warming. In this study,
thermal properties of frozen soil with different moisture contents under
subzero temperature (0°C - 20°C) in an alpine forest
in western Sichuan were analyzed by KD2 Pro in its cooling and
heating processes, respectively. Our results reveal that the soil apparent
volumetric specific heat capacity (Cv) and apparent thermal conductivity (K) under the same water content show similar response patterns to changing temperature lower than -2°C in both heating and
cooling processes. Moreover,
ice content of frozen soils can be well predicted by Logistic model in cooling
and heating processes. The Cv and K tend to increase along with increasing soil moisture contents. Remarkably, asymptotic characters of the value
of Cv and K are at the vicinity of the initial
temperature of phase transitions, indicating that both Cv and K are particularly sensitive to changing
soil temperature at the range of -2°C to 0°C. Therefore, the widely
distributed frozen soil layers with temperature above -2°C in alpine and subalpine zones over Qinghai-Tibetan Plateau are
susceptible to the observed climate warming during cold season.