Arsenic uptake by Pteris vittata in a subarctic arsenic-contaminated agricultural field in Japan: An 8-year study
Arsenic uptake by Pteris vittata in a subarctic arsenic-contaminated agricultural field in Japan: An 8-year study
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DOI：
10.1016/j.scitotenv.2022.154830
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发表时间：
2022-04-01
影响因子：
9.8
通讯作者：
Miyauchi, Keisuke
中科院分区：
文献类型：
--
作者：
Kohda, Yi Huang-Takeshi;Endo, Ginro;Miyauchi, Keisuke
研究了砷（As）超富集植物凤尾蕨（Pteris vittata）对废弃金矿附近农田As污染的修复潜力。试验田位于日本东北部的亚北极地区。本研究的目的是降低土壤中的砷（水溶性砷）的风险，培育土壤和尊重植物的生命周期的可持续植物修复8年。每年春天，这片土地都会被耕种，并种植新的蕨类植物幼苗，每年秋天都会收获长成的蕨类植物。每年收获后，分别对蕨类植物的生物量和叶、根茎和根中的砷浓度进行了分析。气象条件的年变化显著影响了沙冬青叶片的生物量，但叶片中砷的浓度维持在100-150 mg/kg干重。在野外试验条件下，沙冬青对砷的富集量高于超富集植物新疆凤尾蕨。单株收获生物量也高于灰叶松。在为期8年的试验结束时，通过植物修复，农田中砷的去除量超过43.5 g/154 m2（折合为2.82 kg/hm 2）。由于植物生长期和土壤翻耕时间较短，土壤中总砷没有出现明显的耗竭。然而，经过8年的植物修复，表层和深层土壤中的水溶性砷（植物可利用且易于被栽培植物吸收）降至10 μ g/L（日本土壤水溶性砷环境质量标准）。这些研究结果表明，在亚北极气候区，热带和亚热带的砷超富集蕨类植物，P. vittata，适用于砷的植物修复。
In this study, the phytoremediation potential of tropical and subtropical arsenic (As) hyperaccumulating fern Pteris vittata in an As contaminated farmland field near an abandoned goldmine was investigated. The tested field is located in a subarctic area of northeast Japan. This study was aimed at decreasing the risk of As in the soil (water-soluble As) with nurturing the soil and respecting the plant life cycle for the sustainable phytoremediation for 8 years. The field was tilled and planted with new seedlings of the fern every spring and the grown fern was harvested every autumn. The biomass and As concentration in fronds, rhizomes and roots of the fern were analyzed separately after harvesting each year. The biomass of the fronds of P. vittata was significantly affected by the yearly change of the weather condition, but As concentration in fronds was kept at 100-150 mg/kg dry weight. The accumulated As in P. vittata was higher than that of As-hyperaccumulator fern Pteris cretica, the native fern in the field trial area. Harvested biomass of P. vittata per plant was also higher than that of P. cretica. More than 43.5 g As/154 m(2 )(convertible to 2.82 kg of As per hectare) was removed from the farmland field by P. vittata phytoremediation at the end of the 8-year experiment. Because of the short-term plant growth period and soil tilling process, total As in soil did not show significant depletion. However, the water-soluble As in the surface and deeper soil, which is phytoavailable and easily taken in cultivated plants, decreased to 10 mu g/L (Japan Environmental Quality Standard for water-soluble As in soil) by the 8-year phytoremediation using P. vittata. These research data elucidate that the tropical and subtropical As hyperaccumulating fern, P. vittata, is applicable for As phytoremediation in the subarctic climate area.