College of Resources and Environment, Qingdao Agricultural University, Qingdao, 266109, China; Department of Environmental Sciences, University of Peshawar, Peshawar, 25120, Pakistan.
College of Resources and Environment, Qingdao Agricultural University, Qingdao, 266109, China.
Chemosphere. 2020 Apr;244:125543. doi: 10.1016/j.chemosphere.2019.125543. Epub 2019 Dec 4.
Environmentally friendly and cost-effective techniques are required to reclaim land degraded during mining activities. Bioaccumulation of heavy metals (HMs) in vegetables grown on contaminated soils can increase human health risks. The potential effects of hardwood biochar (HWB) was assessed for chromium (Cr), zinc (Zn), copper (Cu), manganese (Mn) and lead (Pb) bioavailability in mine-contaminated soils and their subsequently bioaccumulation in crops and associated health risk. HWB was applied to chromium-manganese mine contaminated soils at the rate of 3% to investigate the efficiency of HWB for the second crop in crop rotation technique. Cilantro (Coriandrum sativum) and spinach (Spinaccia oleracea) were grown as second crop in the same pots which were already used for rice cultivation as first crop (without adding further amendments). Application of HWB decreased the concentrations of Cr, Zn, Cu, Mn, and Pb in cilantro by 25.5%, 37.1%, 42.5%, 34.3%, and 36.2%, respectively as compared to control. In spinach, the reduction in concentrations of Cr was 75.0%, Zn 24.1%, Cu 70.1%, Mn 78.0%, and Pb 50.5% as compared to control. HWB significantly (P < 0.01) reduced the HMs uptake in spinach cultivated in the amended soils as compared to the spinach in control. Bioaccumulation factor results also indicate that HWB decreased the bioaccumulation of selected HMs in cilantro and spinach, thus reducing health risks. Results of the study clearly demonstrate that the use of HWB can significantly reduce HMs in vegetables, associated health risk and improve food quality, therefore can be used as soil amendment for reclamation of mine-degraded soils.
需要采用环保且具成本效益的技术来复垦采矿活动造成的土地退化。生长在受污染土壤上的蔬菜对重金属（HM）的生物累积，会增加人体健康风险。本研究评估了硬木生物炭（HWB）对受铬矿和锰矿污染土壤中铬（Cr）、锌（Zn）、铜（Cu）、锰（Mn）和铅（Pb）生物有效性及其在作物中的生物累积和相关健康风险的潜在影响。将 HWB 以 3%的比例应用于铬锰矿污染土壤，以研究其在轮作技术中对第二茬作物的效率。在同一花盆中种植了香菜（Coriandrum sativum）和菠菜（Spinaccia oleracea）作为第二茬作物，这些花盆之前已用于第一茬作物（水稻）的种植（未添加其他改良剂）。与对照相比，HWB 的应用使香菜中 Cr、Zn、Cu、Mn 和 Pb 的浓度分别降低了 25.5%、37.1%、42.5%、34.3%和 36.2%。在菠菜中，Cr 的浓度降低了 75.0%，Zn 降低了 24.1%，Cu 降低了 70.1%，Mn 降低了 78.0%，Pb 降低了 50.5%。与对照相比，HWB 显著（P<0.01）降低了经改良土壤中菠菜对 HMs 的吸收。生物累积因子的结果也表明，HWB 降低了香菜和菠菜中选定 HMs 的生物累积，从而降低了健康风险。研究结果清楚地表明，HWB 的使用可以显著降低蔬菜中的 HMs、相关健康风险并提高食品质量，因此可以用作受矿山退化土壤的土壤改良剂。
