Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Guangdong, Foshan 528000, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Zhejiang A&F University, Zhejiang, Hangzhou 311300, China.
Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Guangdong, Foshan 528000, China; University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water, and Waste-Management, Laboratory of Soil, and Groundwater-Management, Pauluskirchstraße 7, 42285 Wuppertal, Germany.
J Hazard Mater. 2021 Apr 5;407:124344. doi: 10.1016/j.jhazmat.2020.124344. Epub 2020 Oct 22.
The aim of this study was to evaluate the effect of raw (RawBC) and iron (Fe)-modified biochar (FeBC) derived from Platanus orientalis Linn branches on the plant growth, enzyme activity, and bioavailability and uptake of As, Cd, and Pb by rice in a paddy soil with continuously flooded (CF) or alternately wet and dry (AWD) irrigation in a pot experiment. Application of RawBC (3%, w/w) significantly increased soil pH, while FeBC decreased it. The FeBC was more effective in reducing As and Pb bioavailability, particularly under the AWD water regime, while RawBC was more conducive in reducing Cd bioavailability under the CF water regime. The FeBC decreased As concentration, but increased concentrations of Cd and Pb in the straw and brown rice, as compared to the untreated soil. Soil catalase and urease activities were enhanced by RawBC, but decreased by FeBC treatment. The FeBC increased the grain yield by 60% and 32% in CF and AWD treatments, respectively. The FeBC can be recommended for immobilization of As in paddy soils, but a potential human health risk from Cd and Pb in FeBC-treated soils should be considered due to increased uptake and translocation of the metals to brown rice.
本研究旨在评估源自悬铃木树枝的原始生物炭（RawBC）和铁（Fe）改性生物炭（FeBC）对淹水（CF）或干湿交替（AWD）灌溉稻田土壤中水稻生长、酶活性以及 As、Cd 和 Pb 生物有效性和吸收的影响。在盆栽试验中，RawBC（3%，w/w）的应用显著提高了土壤 pH 值，而 FeBC 则降低了土壤 pH 值。在 AWD 水管理条件下，FeBC 更有效地降低了 As 和 Pb 的生物有效性，而在 CF 水管理条件下，RawBC 更有利于降低 Cd 的生物有效性。与未处理土壤相比，FeBC 降低了稻草和糙米中的 As 浓度，但增加了 Cd 和 Pb 的浓度。RawBC 提高了土壤过氧化氢酶和脲酶的活性，但 FeBC 处理则降低了这些酶的活性。在 CF 和 AWD 处理中，FeBC 分别使稻谷产量增加了 60%和 32%。由于 FeBC 处理土壤中 Cd 和 Pb 的吸收和转运增加，可能会对人体健康造成风险，因此，FeBC 可推荐用于固定稻田中的 As。
