Extended Data Fig. 8: Locations of collected studies and soil nitrogen response to warming across the permafrost-affected regions.
From: Progressive decline in soil nitrogen stocks with warming in a Tibetan permafrost ecosystem
a, Soil N response was collected in 38 datasets from 29 warming experiments at Arctic, subarctic and Tibetan alpine sites. Panel a adapted with permission from ref. 84, Elsevier. b, Mean soil N response to warming (Hedges’s SMD) for all sites, Arctic, subarctic and Tibetan alpine regions. In b, data were visualized as violin plots with outer shape denoting the kernel density estimation of underlying distributions. The white circle in the violin represents the metaregression model estimates, and the error bar denotes 95% confidence interval. The effect of warming was statistically significant if the 95% confidence interval did not overlap zero. Bubble sizes reflect the weight of the observation in the metaregression model. The sample size (n) for each region is indicated in the parenthesis. Abbreviations: Hedges’s SMD; the Hedges’ standardized mean difference. See Supplementary Table 4 for details.
