Chen Guoliang, Liu Xingmei, Brookes Philip C, Xu Jianming
a Institute of Soil and Water Resources and Environmental Science, Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition , Zhejiang University , Hangzhou , China.
Int J Phytoremediation. 2015;17(1-6):249-55. doi: 10.1080/15226514.2014.883496.
The identification of plants with high arsenic hyperaccumulating efficiency from water is required to ensure the successful application of phytoremediation technology. Five dominant submerged plant species (Vallisneria natans (Lour.) Hara., Potamageton crispus L., Myriophyllum spicatum L., Ceratophyllum demersum L. and Hydrilla verticillata (L.f.) Royle) in China were used to determine their potential to remove As from contaminated water. V. natans had the highest accumulation of As among them. The characteristics of As accumulation, transformation and the effect of phosphate on As accumulation in V. natans were then further studied. The growth of V. natans was not inhibited even when the As concentration reached 2.0 mg L(-1). After 21 d of As treatment, the bioconcentration factor (BCF) reached 1300. The As concentration in the environment and exposure time are major factors controlling the As concentration in V. natans. After being absorbed, As(V) is efficiently reduced to As(III) in plants. The synthesis of non-enzymic antioxidants may play an important role under As stress and increase As detoxication. In addition, As(V) uptake by V. natans was negatively correlated with phosphate (P) uptake when P was sufficiently supplied. As(V) is probably taken up via P transporters in V. natans.
为确保植物修复技术的成功应用，需要从水中鉴定出具有高砷超积累效率的植物。选用了中国的五种优势沉水植物物种（苦草、菹草、穗状狐尾藻、金鱼藻和黑藻）来测定它们从受污染水中去除砷的潜力。其中苦草的砷积累量最高。随后进一步研究了苦草中砷的积累、转化特性以及磷酸盐对砷积累的影响。即使砷浓度达到2.0 mg L(-1)，苦草的生长也未受到抑制。经过21天的砷处理后，生物富集系数（BCF）达到1300。环境中的砷浓度和暴露时间是控制苦草中砷浓度的主要因素。砷(V)被吸收后，在植物中能有效地还原为砷(III)。非酶抗氧化剂的合成可能在砷胁迫下发挥重要作用，并增加砷的解毒作用。此外，当磷供应充足时，苦草对砷(V)的吸收与磷的吸收呈负相关。苦草中砷(V)可能是通过磷转运体吸收的。
