土壤盐渍化和重金属污染已成为世界性的环境问题,世界众多地区同时受到高浓度可溶性盐和重金属污染,其对人体健康构成严重威胁,盐土的重金属污染问题引起人们的广泛关注。与甜土植物相比,盐土植物可在含有高浓度Na+和Cl-的盐土中生存甚至旺盛生长,因此更利于植物修复盐土重金属污染。近年来,国内外众多学者相继开展了盐土植物修复重金属污染盐土的研究,一系列重要研究成果被报道,鉴于有关盐土植物提取修复重金属污染盐土的综述尚罕见报道,综述了盐土植物对盐和重金属胁迫的耐性机理、植物提取修复潜力及其影响因素的最新研究进展,并对盐土植物提取修复的可行性、植物修复效率、局限性和挑战进行了深入讨论,对未来研究方向进行了展望。以期为今后盐土植物提取修复盐土重金属污染提供有益参考。
Soil salinization and heavy metal contamination have been global environmental problems. Many regions throughout the world are simultaneously contaminated by high concentrations of soluble salts and heavy metals, posing serious risks to human health. Heavy metal pollution in saline soil has caused increasing concerns. Compared with glycophytes, halophytic plants can survive, even thrive, in saline soil containing high concentrations of sodium and chloride ions, and are thus more suitable for phytoremediation of heavy metal pollution in saline soil. In recent years, many researchers in China and abroad have gradually carried out studies on phytoremediation of heavy metal contaminated saline soil by use of halophytes and a series of important research results has been reported. However, review articles dealing with phytoextraction of heavy metal pollution in saline soil are still scarce. Therefore, this paper reviewed recent progress in the mechanisms of halophyte tolerance to salt and heavy metal stresses, the phytoextraction potential of halophytes and the main factors influencing phytoextraction potential. Moreover, the feasibility of utilizing halophytes for phytoextraction, the phytoextraction efficiency, as well as the limitations and the challenges of phytoextraction by halophytes are also fully discussed. Finally, future research directions are proposed so as to provide useful references for phytoextraction of heavy metal contaminated saline soil in the future.