Optimum biochar preparations enhance phosphorus availability in amended Mollisols of Northeast China

Ying Han, Xiangwei Chen, Enheng Wang, Xiangyou Xia
2019 Chilean Journal of Agricultural Research  
Biochar amendment to soils can improve soil P availability, but details on the optimum application of biochar to black soils in Northeast China are limited. Three types of biochar were produced at six pyrolysis temperatures (between 200 and 700 °C) and then added to black soil samples. P adsorption-desorption isotherms were fitted by the Langmuir model to evaluate the changes in soil P adsorption-desorption after biochar amendment. Changes in P adsorption and desorption depended on biochar
more » ... tock type and pyrolysis temperature. When pyrolysis temperature increased up to 400 °C, P sorption maximum (Qm) of soybean pod (SP) and soybean straw (SS) biochar-amended soils were enhanced from 855.65 and 428.84 mg kg -1 to 1666.67 and 1547.62 mg kg -1 , respectively, while a further increase in the pyrolysis temperature lowered the adsorption capacity. However, P adsorption of corncob (CC) biochar amended soils declined from 1428.57 mg kg -1 to 556.70 mg kg -1 as pyrolysis temperature increased. Higher P desorption in SP and SS compared with CC indicated that SP and SS biochar produced at higher than 400 °C pyrolysis temperatures were considered to be the optimum biochar to enhance P availability in the black soils of Northeast China.
doi:10.4067/s0718-58392019000100153 fatcat:urg4pbjxlfhghlzo423zcmae4q