Research progress and prospect of phytoremediation technology for iron tailings waste land

Phytoremediation technology plays an important role in soil remediation in China.Different plants have different remediation effects and mechanisms on heavy metals or pollutants.Phytoremediation can be divided into four basic types:plant degradation, plant extraction, plant volatilization and plant stabilization.For the phytoremediation of abandoned iron tailings, it is necessary to conduct the local ecological ontology survey.According to different site conditions, local plants with strong adaptability, barren tolerance, drought tolerance and heavy metal pollution tolerance are selected to reconstruct the ecological system of abandoned iron tailings.Through a series of applied studies, there should be corresponding technical methods and selection tendencies in plant community establishment, pioneer species selection and plant collocation.For example, in the establishment of plant community, the collocation of trees, shrubs and herbs should be used as much as possible to form a diverse layer structure, so as to achieve the effect of mutual complement.In terms of pioneer species selection, the legumes with nitrogen fixation ability had better effects, which could be used to achieve rapid community succession.In terms of plant collocation, try to consider different combinations of evergreen and deciduous species, annual and perennial, deep-rooted and shallow-rooted.In terms of theoretical research and practice, phytoremediation is still at the basic stage and requires multidisciplinary and multi-dimension research.Further research and improvement are still needed in the future in terms of enrichment plant screening, phytoremediation effect evaluation, maintenance and management, post-collection, and community succession.