Li Xiaogang, Xiao Jiang, Gai Xu, Du Zhongyu, Salam Mir Md Abdus, Chen Guangcai
Research Institute of Subtropical Forestry, Chinese Academy of Forestry, Hangzhou, Zhejiang 311400, China.
School of Forest Sciences, University of Eastern Finland, Yliopistokatu 7, 111, 80100 Joensuu, Finland.
Sci Total Environ. 2023 Jun 10;876:163245. doi: 10.1016/j.scitotenv.2023.163245. Epub 2023 Mar 31.
Phytoremediation using trees combined with soil amendments has gained much attention for its highly cost-effective trait. In natural field conditions, however, the results may not reflect the true performance of amendments based on short-term laboratory studies. In this three-year field trial, various soil amendments such as rice straw biochar, palygorskite, a combined biochar of rice straw biochar and palygorskite, and hydroxyapatite were used to systematically study the potential of the low-accumulator (Quercus fabri Hance) and high-accumulator (Quercus texana Buckley) for cadmium (Cd) and zinc (Zn) to remediate severely contaminated soils. Soil amendments enhanced the dendroremediation capacity of Quercus as the growth period prolonged. In 2021, the rice straw biochar treatment increased Cd and Zn accumulation by 1.76 and 2.09 times in Q. fabri, respectively, compared to the control. Cd and Zn accumulation increased to 1.78 and 2.10 times, respectively, under combined biochar treatment for Q. texana compared to the control. Metals accumulation was mainly enhanced by soil amendments through increasing the growth biomass of Q. fabri and improving the biomass and bioconcentration ability of Q. texana. Overall, soil amendments effectively improved the phytoremediation efficiency of Quercus in the long term, and selecting suitable amendments should be fully considered in phytoremediation.
利用树木结合土壤改良剂进行植物修复因其高性价比的特性而备受关注。然而，在自然田间条件下，基于短期实验室研究的结果可能无法反映改良剂的真实性能。在这项为期三年的田间试验中，使用了各种土壤改良剂，如稻草生物炭、坡缕石、稻草生物炭与坡缕石的复合生物炭以及羟基磷灰石，系统地研究了低积累树种（麻栎）和高积累树种（德克萨斯栎）对镉（Cd）和锌（Zn）修复重度污染土壤的潜力。随着生长周期的延长，土壤改良剂提高了栎属植物的树木修复能力。2021年，与对照相比，稻草生物炭处理使麻栎中Cd和Zn的积累分别增加了1.76倍和2.09倍。与对照相比，德克萨斯栎在复合生物炭处理下Cd和Zn的积累分别增加到1.78倍和2.10倍。土壤改良剂主要通过增加麻栎的生长生物量以及提高德克萨斯栎的生物量和生物富集能力来增强金属积累。总体而言，从长期来看，土壤改良剂有效地提高了栎属植物的植物修复效率，在植物修复中应充分考虑选择合适的改良剂。
