| Autor: |
Tong-Yao Pu, Zhao-Feng Yuan, Jia-Yue Wang, Wei-Jia Feng, Xianjin Tang, Williamson Gustave, Yong-Guan Zhu, Yi-Li Cheng, Jonathan Bridge, Chen-Yu Jin, Zheng Chen |
| Rok vydání: |
2022 |
| Předmět: |
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| Zdroj: |
Journal of Hazardous Materials. 439:129626 |
| ISSN: |
0304-3894 |
| DOI: |
10.1016/j.jhazmat.2022.129626 |
| Popis: |
Arsenic (As) pollution in paddy fields is a major threat to rice safety. Existing As remediation techniques are costly, require external chemical addition and degrade soil properties. Here, we report the use of plastic tubes as a recyclable tool to precisely extract As from contaminated soils. Following insertion into flooded paddy soils, polyethylene tube walls were covered by thin but massive Fe coatings of 76.9-367 mg Fe m-2 in 2 weeks, which adsorbed significant amounts of As. The formation of tube-wall Fe oxides was driven by local Fe-oxidizing bacteria with oxygen produced by oxygenic phototrophs (e.g., Cyanobacteria) or diffused from air through the tube wall. The tubes with As-bound Fe oxides can be easily separated from soil and then washed and reused. We tested the As removal efficiency in a pot experiment to remove As from ~ 20 cm depth/40 kg soils in a 2-year experiment and achieved an overall removal efficiency of 152 mg As m-2 soil year-1, comparable to phytoremediation with the As hyperaccumulator Pteris vittata. The cost of Fe hooks was estimated at 8325 RMB ha-1 year-1, and the profit of growing rice (around 16080 RMB ha-1 year-1 can be still maintained. The As accumulated in rice tissues was markedly decreased in the treatment (>11.1%). This work provides a low-cost and sustainable soil remediation method for the targeted removal of As from soils and a useful tool for the study and management of the biogeochemical Fe cycle in paddy soils. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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