Аннотация:Obtained data show the dynamics of intensity and direction of the
heat flux in soils. They reflect daily, annual or long-term changes of the
thermal state of soil massif, depending of the depth of heat flux sensor
and measure period.
Effective heat capacity and thermal conductivity of the soil was
calculated using the temperature and heat flux intensity data. The
equation of heat balance for soil layer was used to estimate the effective
heat capacity of soil. The heat conduction equation was used to calculate
the effective thermal conductivity of the soil.
The calculated average value of the effective thermal conductivity
is 1.4 W/(m*K) at the first monitoring point. The effective thermal
conductivity varies from 1.1 W/(m*K) to 1.9 W/(m*K) here. Effective
heat capacity averages 2.2 kJ/(kg*K) and varies from 0.3 kJ/(kg*K) to
8.1 kJ/(kg*K). Similar amplitude fluctuations of effective thermophysical coefficients were found at other monitoring Sites.
We explain the observed changes in the effective soil thermal
conductivity and heat capacity by the heat effects of processes inside soil
massif such as phase transitions during freezing and thawing, evaporation
and condensation, convection of mobile phases, also by heat effects of
chemical reactions, interfacial interactions, and biochemical
transformations.
The obtained data allowed us to improve any design features the
system for soil heat flux monitoring. The results show the feasibility of
the using the heat flux data for the geocryological monitoring.