Insert Fig. 2
The SOC and TN storages calculated by the FD and ESM methods showed
significant
variations
(Fig. 2). The deviations should be caused by the
inequal soil mass that induced by
variations of soil BD
(Vandenbygaart and Angers, 2006; Wiesmeier et al., 2016). In this study,
large sample statistics were carried out on BD, and the results showed
that BD increased significantly after deforestation (Fig. 2c,lnRR = 0.09, P < 0.05), and decreased
significantly after land restoration (Fig. 2c, lnRR = -0.02,P < 0.05). Therefore, when LUCC increased soil mass
(i.e., higher soil BD), the FD underestimated the loss of SOC/TN
storage. By contrast, when LUCC
decreased soil mass, the FD overestimated the SOC/TN storage. Thus, the
ESM were found to be more accurate in capturing SOC/TN storage changes
and we only adopted the ESM for the following analysis.