Spatial variation and allocation of sulfur among major plant organs in China.

Sulfur (S) is a functional element that plays an important role in abiotic stress resistance and environmental adaptation in plants. However, knowledge of the biogeographic patterns of S among major plant organs remains limited. We conducted a methodologically consistent field survey of 2745 plant species across 78 typical communities throughout China. From this, we constructed a new matched database of S content in leaves, twigs, trunks, and roots to explore S allocation strategies in plants to better understand the regulatory mechanisms on a large scale. The average S content in leaves, twigs, trunks, and roots of plants in China was 2.32 ± 0.04, 1.13 ± 0.02, 0.15 ± 0.01, and 1.23 ± 0.02 g kg, respectively. S content was significantly higher in leaves than in other organs, and S content of plants in deserts was higher than that of plants in forests and grasslands. S content changed faster in roots and showed divergent allocation relationships among organs across communities at different scales. Climate and soil properties jointly regulated the spatial variation and allocation relationships of S among different organs. This study further broadens our understanding of the biological functions of S and their role in the interactions between plants and the environment.