title: Effective alleviation of aluminum phytotoxicity by manure-derived biochar.
abstract: The alleviation of aluminum phytotoxicity to wheat plants in a hydroponic system through the amendment of biochar is investigated to explore the possibility of applying biochar in acidic soil amelioration. Biochar derived from cattle manure pyrolyzed at 400 °C (CM400) and the CM400 biochar washed with distilled-deionized water to remove alkalinity (WCM400) were prepared to determine the roles of the liming effect and adsorption during the alleviation of Al toxicity. Upon addition of 0.02% (W/V) CM400 to the exposure solution, the inhibition of plant growth by Al was significantly reduced while the toxic threshold was extended from 3 to 95 μmol/L Al(3+). Due to the biochar liming effect, the aluminum species were converted to Al(OH)(2+) and Al(OH)2(+) monomers, which were strongly adsorbed by biochar; furthermore, the highly toxic Al(3+) evolved to less toxic Al(OH)3 and Al(OH)4(-) species. Adsorption of Al by the biochar is dominated by surface complexation of the carboxyl groups with Al(OH)(2+)/Al(OH)2(+) rather than through electrostatic attraction of Al(3+) with negatively charged sites. Compared to the liming effect, the adsorption by biochar exhibited a sustainable effect on the alleviation of Al toxicity. Therefore, the biochar amendment appears to be a novel approach for aluminum detoxification in acidic soils.
authors: Department of Environmental Science, Zhejiang University, Hangzhou 310058, China.
authors: Linbo
authors: L
authors: Qian
authors: Baoliang
authors: B
authors: Chen
authors: Dingfei
authors: D
authors: Hu
mesh_terms: D000327:Adsorption; D000535:Aluminum / Q000302:isolation & purification / Q000633:toxicity*; D000818:Animals; D002417:Cattle; D002606:Charcoal / Q000737:chemistry*; D008372:Manure / Q000032:analysis*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000302:isolation & purification / Q000633:toxicity*; D014908:Triticum / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development
chemical_list: D008372:Manure; D012987:Soil; D012989:Soil Pollutants; C540010:biochar; D002606:Charcoal; D000535:Aluminum