Plant type dominates fine-root C:N:P stoichiometry across China: A meta-analysis

Aim Fine roots play an important role in biogeochemical cycling in terrestrial ecosystems. However, our understanding of large scale biogeographical patterns and drivers of fine-root C:N:P stoichiometry is extremely limited. Location China. Methods We compiled data for fine-root carbon (C), nitrogen (N) and phosphorus (P) concentrations at 165 sites across China to explore large-scale biogeographical patterns and drivers of fine-root C:N:P stoichiometry. Results The geometric means of fine-root C, N, and P concentrations were 448.81, 10.73, and 0.9 mg/g, respectively, whereas C:N, C:P, and N:P ratios were 41.84, 508.32, and 11.73, respectively. The fine-root elemental concentrations and their ratios varied widely among plant groups and biomes, and showed clear latitudinal and longitudinal trends, as a consequence of differences in climate, soil, and plant type. However, plant type was the largest contributor to the total variance in fine-root C, N, and P and their ratios compared to climate factors or soil features. Main conclusions The data reveal the existence of broad biogeographical patterns of fine-root C:N:P stoichiometry in China. These results advance our knowledge about the biogeochemical cycling of fine roots.