Bamboo char adsorption efficiency on soil nitrate anions

Abstract

Biochar with a huge active surface area can absorb anions, such as nitrate, in soils. To test adsorption efficiency of bamboo char on nitrate anions of soils, two types of soils (natural and cultivated) and two sizes of bamboo char particles[1-2 mm with bamboo char percentages of 0(control, ck), 1%, 3%, and 5% and 0.05) for soils with more than 3% bamboo char. For the first two leachings, when soils treated with equivalent amounts of bamboo charcoal (3%) were compared to ck, the soil with the 1-2 mm size bamboo char had a significantly higher (P < 0.05) absorption capacity for nitrate anions than the < 1 mm and ck. During the third leaching, significant differences (P < 0.05) were observed between ck and soils with bamboo char(both < 1 mm and 1-2 mm size). Thus, absorption efficiency of anions was related to both proportion and particle diameter of bamboo charcoal with 3% bamboo char at 1-2 mm diameter being the most economical rate to reduce soil nitrate leaching.