Surface soil treatment experiment
In order to test whether surface soil treatment could improve the germination rate of native seeds, a pair of biochar treatment and control plots (3.6 m x 1.8 m each) were set at each of the three landslide sites. Biochar powder (0.62kg/m2) were mixed with surface soil (around 3 cm at the top) in each treatment plot. Each plot was sub-divided into four equal grids as four species were tested (Table 1). For each species, 60 plain seeds were planted in one grid of each plot (Figure 1 and 2b).