Fig. 1: Location and settings of study sites.

a Map of China highlighting peatland distributions67 with the domain of the QTP outlined by red lines (the areas with elevation >3000 m a.s.l.)68. b Aerial view showing the locations of study cores C1 to C6 (Google Earth image). c Schematic plot of the coring sites with the slope transect indicated by the yellow line in (b). Elevations are derived from a digital elevation model based on UAV aerial imagery36. The UAV aerial image is shown in the bottom left. d Photograph of the hummock-to-pool transect next to the coring location of core C5. Black triangles in (a) denote other sites discussed in the text: 1 – Maduo Xiang wetland37, 2 – Koucha lake32, 3 – ZigetangCo lake31, 4 – Dangxiong wetland33.