Results

Our study plots covered a range of topographic, vegetation and microclimatic conditions (Figure 2c). Plots were distributed between 53 m and 773 m a.s.l. and experienced solar radiation values between 0.81 SRI and 0.96 SRI. Relative positioning of plots in the landscape varied as well, with TPI ranging from -3.9 to 1.9 and TWI ranging from 4.3 to 10.6. Vegetation contexts varied widely, from almost barren plots (minimum 5 % cover) to densely vegetated plots with overlapping vegetation layers (maximum 168 % cover), also reflected in plant communities’ variable leaf economic and size traits (Figure S1). Similarly, plots covered a range of soil conditions regarding nutrient content and texture (Figure S2). Finally, microclimate differed largely across plots, with accumulated soil temperatures over the incubation period ranging from 593 to 2200 GDD0, and scaled mean growing-season volumetric soil moisture ranging between 2.8 and 68.9 % (Figure 2c).
Median mass loss in Green Tea and Rooibos Tea across sample plots was 60.3 % (95 % confidence interval: 51.1 – 71.9 %) and 24.8 % (18.6 – 31.4 %), respectively, over the approx. 14 months of incubation (Figure 3a,S3). Median decomposition rate k was 0.002 (0.0015 – 0.0040) and median stabilisation factor S was 0.284 (0.141 – 0.393; Figure 3b). These values were generally comparable to other studies from across the tundra biome (Figure 3), with relatively low values for k reflecting a slightly longer incubation time than those observed by other studies (Table S2).