At Fig. 1 Dynamics of soil pH during the incubation with rice
hull (20 g kg−1) and rice hull biochar (20 g kg−1). Vertical bars represent the standard error of the mean (n = 3). the end of the incubation, soil NH+4 -N for rice hull
treatment was much higher than that for rice hull
biochar and controls (P < 0.01), while there was a
reverse trend for soil nitrate (Fig. 2) (P < 0.01). The
inhibition of nitrification reduced H+ release and increased
soil pH.