Fig. 5: Variation in mercury (Hg) isotopic composition across soil, vegetation, and region.
From: Root uptake dominates mercury accumulation in permafrost plants of Qinghai-Tibet Plateau
a Comparison of slope for Δ199Hg versus Δ201Hg, b Hg concentrations, c Δ199Hg values in vegetation and 0–30 cm depth surface soils, d biomass ratio of root to shoot between the permafrost of QTP and Arctic tundra. Data of Hg concentration and isotopic compositions of Arctic tundra are based on literature synthesis5,6,10,11,58, including the regions of Alaska and Siberia, and the ratio of root to shoot for the grass species in the QTP and tundra are both from earlier studies60,61,62. Error bars stand for 1σ in a. Boxplot elements in b–d show the median (midline), the interquartile range of 25% and 75% percentile (box boundaries), data points within the 1.5 × quartile range (whiskers).
