環境

[PY-58] Evaluation of Cd and Zn adsorption by Arabidopsis halleri ssp. gemmifera in hydroponic culture

^○宋陽¹, 文霞^1,2, 菅原一輝^1,3, 黄毅⁴, 宮内啓介⁴, 遠藤銀朗⁴, 北島信行⁵, 迫田昌敏⁶, 井上千弘¹ (1.東北大学大学院環境科学研究科, 2.清華大学, 3.独立行政法人日本学術振興会 特別研究員, 4.東北学院大学工学部, 5.株式会社フジタ, 6.石油天然ガス・金属鉱物資源機構)

Keywords:ハクサンハタザオ, カドミウム, 水耕栽培, ファイトレメディエーション

In Japan, many abandoned mines remain and some of them still release mine drainage containing heavy metals such as Cd and Zn. Arabidopsis halleri ssp. gemmifera, known as the Cd and Zn hyperaccumulator, has been applied in remediation of Cd contaminated soil of several farmland. Although A. halleri ssp. gemmifera has a potential to be applied to Cd contaminated water, there is no trial to apply this plant to the wastewater treatment such as mine drainage. In our previous result of hydroponic cultivation in a laboratory, A. halleri ssp. gemmifera showed uptake ability of Cd or Zn in its single system. In this work, we conducted research on Cd and Zn uptake of this plant in hydroponic culture using solutions containing mixture of Cd and Zn with different ratio. 4 month-old plants were pre-cultured in 5× diluted Hoagland solution during 2 weeks and transferred to Cd and Zn added MES solution (pH 5.5). After 96 hours of adsorption experiment, concentrations of Cd and Zn in the solution were decreased significantly and two metals were accumulated in the plant. The final Cd concentration in solution were lower than the Japanese environmental standard for Cd concentration in water (0.003 mg l^-1) when initial Cd concentration was lower than 0.05 mg l^-1. The transfer of Cd to the plant was faster than that of Zn even at lower Cd/Zn ratio. These results suggest that A. halleri ssp. gemmifera has a potential to be used in a treatment of mine drainage containing Cd and Zn.