Fig. 4. Formation efficiencies of aboveground, roots, belowground inputs (roots + net rhizodeposition), and net rhizodeposition into particulate organic carbon (POC_FE) and mineral-associated organic carbon (MAOC_FE) in litter incubation experiments or living plant experiments.

Panel A shows POC_FE and panel B shows MAOC_FE. Boxes, interquartile distance; line in the box, median; crosses, mean; whiskers, maximum and minimum non-outlier; circles, outliers; the value was considered to be an outlier if it was at least 1.5 interquartile ranges below the first quartile, or at least 1.5 interquartile ranges above the third quartile. Numbers described the sample size, and different letters indicate statistical significance (P < 0.05). Rhizodeposition formation efficiencies in living plant experiments were estimated considering a net rhizodeposition:root ratio of 0.5 ± 0.1 and assuming root-input-POC_FE and root-input-MAOC_FE as the median of litter incubation experiments (see Eqs. 3 and 4). POC_FE measurements made before the break point time in Fig. 3 were corrected to the break point time using the relative decay rates (76% year⁻¹ for aboveground and 79% year⁻¹ for root and belowground inputs; see Table 3 and the Supplementary Materials for details)