a C, FT, R, R + FT stand for the control,
freeze-thaw,
root
system and root system + freeze-thaw treatments, respectively.
b Lowercase letters in this line indicate a
significant difference for different treatments of sand soil at P< 0.05. The capital letters in this line indicate a
significant difference for different treatments of loessal soil atP < 0.05.
Table 3 Regression relationships between soil detachment
capacity (SDC) and hydraulic parameters of sand soil