Fig. 3.

Effect of biochar diameter on adsorption of Cd (a) and SMX (b) on rice straw biochar

d 150, d 250, and d 425 represent biochars with diameters <150, 150–250, and 250–425 μm, respectively. ^* P<0.05, ^** P<0.01: significant differences between SMX solely and in combination with Cd at each diameter