Abstract: Based on the data from field experiments, the effect of peach orchard intercropped with rye grass on soil thermal regime is analysed and simulated. Under cloudy condition, the average soil volumetric heat capacity in areas with and without rye grass intercropping is 2.54 and 2.53 J·cm^-3·℃^-1, soil temperature conductivity is 16.9 and 10.4 cm² ·h^-1,and average soil net heat flux is 136.6 and 167.6 J·cm^-2·d^-1 respectively. Under sunny condition, they are respectively 2.93 and 2.61 J·cm^-3·℃^-1, 16.3 and 5.8 cm²·h^-1, and 80.4 and 85.2 J·cm^-3·d^-1. Soil temperature at different depths is mostly in the form of first-order sine wave, its amplitude with depth shows an exponential function, the decay coefficient is greater in the area without intercropping than in rye grassplanted one, and the phase delay of soil temperature with depth is 0.4 h·cm^-1.

Key words: Peach orchard, Rye grass intercropping, Soil thermal regime, Simulation study, nitrogen and phosphorous, simulated warming, alpine timberline, soil microbial community, phospholipid fatty acid, soil carbon