Spatial variation of temperature of surface soil layer adjacent to constructions: A theoretical framework for atmosphere-building-soil energy flow systems

Lack of concern for spatial variation of urban soil temperature does not reflect the importance of soil temperature in ecosystem service. The method of construction-soil micro gradient transects (CSMGT) and in situ observations were applied in this study to understand the mechanism of higher soil temperatures in urban areas and the spatial variation of the temperature of surface soil layer adjacent to constructions. Based on experimental data, a new theoretical framework for atmosphere-building-soil energy flow systems was established to analyse the changing rate of the temperature of surface soil layer (R-s) adjacent to constructions. The results of redundancy analysis and hierarchical partitioning showed horizontal heat flux between building and soil (HHF0) played a very important role in driving Rs along the CSMGT at night, whereas joint effects of multiple energy factors drove it during daytime or on the scale of an entire day. Moreover, a formula was fitted to express the temperature of surface soil layer (Ts) along the CSMGT. Each parameter (a, b and c) of the equation was significant relative to energy or meteorological factors (P < 0.01), and the distribution of the P value of parameter b matched the results of the redundancy analysis and hierarchical partitioning. (C) 2017 Published by Elsevier Ltd.