Fe/Al (hydr)oxides engineered biochar for reducing phosphorus leaching from a fertile calcareous soil. (10th January 2021)

• Record Type: Journal Article
• Authors: Peng, Yutao; Sun, Yuqing; Fan, Bingqian; Zhang, Shuai; Bolan, Nanthi S.; Chen, Qing; Tsang, Daniel C.W.
• Is Part Of: Journal of cleaner production. Volume 279(2021)
• Publication Date: 2021-01-10
• Subjects: Engineered biochar -- Phosphorus leaching -- Sustainable waste management -- Soil amendment -- Resource recovery -- Agricultural soil; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2020.123877
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Excessive input of phosphate fertilizer into agricultural soils has caused critical environmental concerns due to high phosphorus (P) accumulation in farmland and P leaching into subsurface drainage. In this study, an Fe/Al (hydr)oxides modified biochar (FA-BC) was fabricated from corn straw via a wet-precipitation method and utilized to reduce P leaching from a fertile calcareous soil. Spectroscopic techniques demonstrated that the FA-BC exhibited a higher oxidation resistance than the raw BC due to oxide impregnation on the BC surface. The maximum Langmuir P adsorption capacities (393 and 528 mg kg −1 ) of the BC (4%, w/w ) and FA-BC (4%, w/w ) treated soils demonstrated a more efficient P adsorption capacity of the FA-BC. Application of the 2% ( w/w ) FA-BC also significantly reduced the leaching of total P (81.3%) from the soil column, while maintained an appropriate level of bioavailable P in the soil for sustaining plant growth. The chemical sequestration test and in-situ P k -edge XANES analyses of the FA-BC incubated soils revealed that the labile Ca–P fractions were transformed into stabilized Fe/Al–P complexes. The increased soil pH, a higher degree of soil P saturation, and intensive interaction between P and Fe/Al (hydr)oxides also contributed to the superior ability of the FA-BC amended soils towards P retention. This study provided field-relevant implications for the design and application of engineered biochar for green and sustainable improvement of agricultural soils. Graphical abstract: Image 1 Highlights: Fe/Al (hydr)oxides (FA) modification enhanced oxidation resistance of biochar (BC). FA-BC amended soil exhibited higher adsorption capacity and retention ability of P. FA-BC transformed labile Ca–P fractions to stabilized Fe/Al–P complexes. FA-BC induced higher soil pH and degree of soil P saturation for less P leaching.