Ecological restoration of man-made habitats, with emphasis on metal-contaminated sites and domestic landfills

Heavy metal contamination of soils and waters has been accompanied with the socioeconomic development in China since the 1970s. China is rich in mineral resources, and extraction and smelting of metals have generated a large amount of mine tailings, leading to severe soil and water contamination. The subsequent uptakes of toxic metals by crops and fish pose human health risks. In addition, domestic and industrial wastes derived from urban centers and industrial areas are disposed of in landfills, which may also exert harmful effects on environmental and public health, through leaching of contaminants from the embedded wastes. Phytoremediation has been used for restoration of these man-made habitats, which include metal mine tailings, metal-contaminated sites (e.g., farm soils), and completed landfills. The present article attempts to review advances made in the past 40 years from our research groups, concerning ecological restoration of these habitats, focusing on the interactions of higher plants and soil organisms, including invertebrates such as earthworms and associated rhizospheric microbes (i.e., fungi and bacteria). Successful ecological restoration of these habitats would depend on the choice of plant species, appropriate combinations with soil organisms, and suitable soil amendments for enhancing plant growth and ecological succession in the highly stressed conditions. Copyright © 2018 Science Press & Springer Nature Singapore Pte Ltd.