Health and Environment Department, AIT Austrian Institute of Technology GmbH, Konrad-Lorenz-Straße 24, 3430, Tulln, Austria.
Institute of Soil Research, University of Natural Resources and Life Sciences, Peter-Jordan-Straße 82, 1190, Vienna, Austria.
Environ Sci Pollut Res Int. 2018 Jan;25(3):2506-2516. doi: 10.1007/s11356-017-0670-2. Epub 2017 Nov 10.
Besides carbon sequestration and improvement of soil properties, biochar (BC) has increasingly been studied as an amendment to immobilise heavy metals in contaminated soils. In a 2-year experiment, we analysed the effects of poplar BC (P-BC, mixed with compost) and gravel sludge with siderite-bearing material (GSFe) on a Cd-, Pb- and Zn-contaminated soil and on metal concentration in Miscanthus × giganteus shoots under greenhouse and field conditions. In the greenhouse, 1% (m/m) P-BC addition reduced NHNO-extractable Cd, Pb and Zn concentrations by 75, 86 and 92%, respectively, at the end of the study. In the leachates, P-BC (1%) could significantly reduce Cd and Zn in both years. In the field, P-BC (3%) induced a reduction of extractable Cd by 87% whereas a combination of P-BC + GSFe reduced Pb by 82% and Zn by 98% in the first year and by 83 and 96% in the second year. In contrast, the metal immobilisation in the soil was hardly reflected in the shoots of Miscanthus × giganteus which generally showed metal concentrations close to control. While Cd was not influenced in both years, Pb and Zn were slightly reduced. Our study confirmed that Miscanthus is an efficient metal excluder, corroborating its suitability for the production of renewable biomass on metal-contaminated soils.
除了碳封存和改善土壤性质外，生物炭（BC）作为一种固定污染物的改良剂，也越来越多地被用于固定污染土壤中的重金属。在为期两年的实验中，我们分析了杨木生物炭（P-BC，与堆肥混合）和含有菱铁矿材料的砾石污泥（GSFe）对 Cd、Pb 和 Zn 污染土壤以及温室和田间条件下杂交狼尾草地上部金属浓度的影响。在温室中，研究结束时，添加 1%（m/m）的 P-BC 可使 NHNO-可提取的 Cd、Pb 和 Zn 浓度分别降低 75%、86%和 92%。在淋出液中，P-BC（1%）在两年内均可显著降低 Cd 和 Zn 的浓度。在田间条件下，添加 3%的 P-BC 可使可提取的 Cd 降低 87%，而 P-BC+GSFe 的组合可使 Pb 降低 82%，Zn 降低 98%（第一年）和 83%和 96%（第二年）。相比之下，金属在土壤中的固定情况并没有反映在杂交狼尾草的地上部，杂交狼尾草的地上部金属浓度通常接近对照。虽然 Cd 在两年内都没有受到影响，但 Pb 和 Zn 略有降低。我们的研究证实，杂交狼尾草是一种有效的金属排斥物，证实了其在污染土壤上生产可再生生物量的适宜性。
