Perspectives on phytoremediation of zinc pollution in air, water and soil

Abstract

In this article, we discuss the phytoremediation of Zn pollution in the environment and the mechanism of plant resistance focusing on the mycorrhiza and subcellular mechanisms affecting metal binding and efflux in plants. Phytoremediation is a green low-cost technology that use plants to remove heavy metals (HMs) from soil. As part of this, it is necessary to consider the plant's tolerance to for example zinc (Zn) together with the plant's ability to accumulate and adapt to the specific local environment. During the process of restoring ecosystem contaminations, pH, organic matter, root exudates and microbial biomass affect the efficiency of phytoremediation while considering chemical modification, biosynthesis, microbial assistance and gene technology. However, obstacles remain in terms of for example chemical modifications that may cause either new pollution or disrupt the plant-microorganism symbiosis while other applications such as genetic engineering to change plant traits and function thereby improving heavy metal tolerance and absorption. The selection of gene fragments is complicated and requiring careful considerations due to environmental and human health side effects. Furthermore, using biochar may help to reduce the costs and increase the efficiency of plant phytoremediation. At the same time, there is an urgent need to combine nanotechnology and use of artificial chelating agents and plant hormones to screen the microbiome conducive to plant Zn absorption in order to improve the efficiency of phytoremediation.