It is worth noting that the area of

It is worth noting that the area of vegetation removal is smallcompared to both the tree height and the vast forest. This is adverseto analogize the effects of extensive vegetation degradation on permafrost. First, the surrounding standing trees will cast shadows onthe experiment spot receiving vegetation removal (plot P4). The received solar radiation may be much smaller than that in the extensivevegetation degradation case. Second, the extensive degradation ofvegetation will increase the wind speed near surface in general. Thewind field change in the vicinity of plot P4 caused by vegetationremoval could almost be negligible because of the untouched thickforest surrounding. The experiment in this study could not reflect the effects of wind speed increase on turbulent flux near surface—forexample, evaporation and snow sublimation. They have both directand indirect effects on ground temperatures. At last, the lateral heatexchange in deep ground between the vegetation removed area andundisturbed forest could not be ignored. Some energy will be lostfrom plot P4 to the surrounding ground in terms of lateral heat flux.The increase in ground temperature at P4 will be offset somewhat,especially at deep soils with small temperature increment. This maybe the underlying reason for the quickly decreased ground temperature difference between P3 and P4. For these reasons, the groundtemperature increases and permafrost degradation will be more severe in case of extensive vegetation degradation, especially in deepsoils. It also will take a longer time for the ground temperature andpermafrost to restore after reforestation