Phytoremediation Potential of Four Native Plants in Soils Contaminated with Lead in a Mining Area

Metal pollution in soils is an issue of global concern, and lead (Pb) pollution is considered to be the most serious type. The arid and semi-arid areas of Northwest China are rich in Pb ore resources. In this study, four native crops [wormwood (Artemisia capillaris), dandelion (Taraxacum mongolicum), alfalfa (Medicago sativa), and plantain (Plantago asiatica L.)] that grow naturally around tailings slag in a mining area in Northwest China were selected to screen their ecological restoration impacts on Pb-contaminated soil. In pot experiments, four different metal lead pollution gradients (0, 2, 3, and 5‰ w/w) were set, and crop growth indexes such as plant height, root length, and biomass, together with the changes of soil Pb content in different tissues and organs before and after planting were analyzed. The results showed the difference in the amount of accumulated Pb in relation to the level of Pb content in the soil. It was found that wormwood and plantain have great potential as remediation plants for soil metal lead pollution in the arid and semi-arid lead bearing mining areas of Northwest China.

Effect of Lead on the Development and Nutrient Accumulation Ability of Musca Domestica

Lead pollution poses a threat to the survival of animals, plants and humans. Environmental pollution conversion with insects is a new type of environmental management. Housefly (Musca domestica) may be an efficient, economical, and safe choice for lead pollution control. However, this needs to make sure that houseflies are strongly resistant to lead contamination. In this study, housefly larvae, pupae and adult growth parameters and adult fecundity under lead treatment were counted, and changes in digestive enzyme activities and gene expression levels were detected to comprehensively analyze the tolerance of housefly to lead exposure. As a result, lead accumulated in the larvae under 5000 mg/kg lead treatment and caused a decrease in the survival rate of the larvae, extension of the developmental duration, decrease of the body weight, and dynamic changes in oviposition dynamics. The total sugar and total protein content of the larvae decreased, while the amylase and trypsin activities decreased, the total lipid content increased, and the lipase activity increased, the expression of all digestive enzyme genes changed. 20 mg/kg lead treatment has no significant effect on the growth and development of housefly. In conclusion, lead exposure mainly affected the growth rate of larvae and adult fecundity by affecting the efficiency of housefly nutrient accumulation.