Method for promoting restoration of mercury contaminated soil plant

Abstract

The invention discloses a method for promoting restoration of mercury contaminated soil plant by using ammonium thiosulfate, which comprises the following steps of: 1) planting rape into mercury contaminated soil; 2) after the rape grows for 2-3 months, adding ammonium thiosulfate solution into the soil, wherein 2-6g of the ammonium thiosulfate is added in per kilogram of soil; and 3) harvesting the plant after the ammonium thiosulfate is added for 3-10 days. The ammonium thiosulfate adopted by the method is pollution-free for the soil, simple in technique and low in cost, has good restoration effect for the mercury contaminated soil, and is applicable to resorting large-area mercury contaminated soil plant.

Description

technical field [0001] The invention relates to a method for using phytoremediation of polluted soil, in particular to a method for phytoremediation of mercury-contaminated soil. Background technique [0002] At present, mercury-contaminated soil is generally repaired by physical and chemical methods. The use of physical and chemical methods to restore mercury-contaminated soil is not only costly, but it is not easy to promote and use on a large scale, and it will cause great damage to soil properties and structures. For example, according to the "U.S. Environmental Protection Agency website, http: / / clu-in.org / s.focus / c / pub / i / 1464 / ", the California Environmental Protection Agency reported that the New Almaden mercury mining area is about 10,000-15,000m 3 The soil is transferred and processed, and only the initial investment per cubic meter reaches 460 US dollars / m 3 . At present, the area of ​​mercury-contaminated soil in the world is large, and the mercury-contaminated cu...

AI Technical Summary

Problems solved by technology

[0003] Reported the ability of pea, spring wheat, sugar beet and clover to accumulate and transport mercury. It was found that although all plant roots can absorb mercury, the mercury transported to the aerial part only accounts for about 0.17%-2.5% of the root mercury content; 2007 The published "International journal of phytoremediation" reported that Rodriguez et al. used crops such as barley, lentils and lupins to repair mercury-contaminated soil, but the repair efficiency was not high. Only the aboveground part of lupine had the highest mercury content, reaching about 1mg / kg

Plant roots have a low capacity to extract and transport mercury

Attempts to increase mercury uptake by plant roots and transport to the aerial parts have been poor

For example, "Science of the Total Environment" published in 2006 reported that some scholars found that KI can promote the uptake of mercury by willow roots but cannot effectively transport mercury to the aboveground parts of plants.

"Environmental Practice" published in 2004 reported that Moreno et al. applied ammonium thiosulfate to slag to study the extraction of mercury from Indian mustard. Although the extraction ability of Indian mustard to mercury was increased, it was not applied to mercury-contaminated soil, because the soil and slag Heap physicochemical properties vary widely and, therefore, remain unresolved