Method for restoring moderately Cd-contaminated soil by using vine and melon vegetables and light eluting agent

Abstract

The invention discloses a method for restoring moderately Cd-contaminated soil by using vine and melon vegetables and a light eluting agent. According to the invention, plantation of vine and melon vegetables and application of the light eluting agent are employed, vegetable cultivation and soil washing are combined together, so heavy metals in soil are allowed to be removed from surface soil posing harm to crops, only a small destructive effect is exerted on soil, and agricultural production can be continued during restoration of heavy metal pollution, which enables production and restoration to be realized at the same time. When the light eluting agent is added into soil, Cd in a cultivation soil layer can be eluted to a deep layer where the root of a crop cannot reach and can be adsorbed by soil. The roots of vine and melon vegetables absorb Cd activated by the eluting agent in contaminated soil; however, activated Cd is generally intercepted by long stems and considerable leaves, little Cd can be delivered to edible parts, i.e., fruits, so harvested fruit vegetables are safe to eat. Harvested stems and leaves of the vegetables can be used as an organic fertilizer, and the content of heavy metals in the stems and leaves accords with standards of an organic fertilizer, thereby causing no secondary pollution.

Description

technical field [0001] The invention belongs to the technical field of Cd-contaminated soil treatment, and in particular relates to a method for repairing moderately Cd-contaminated soil by using rattan vegetables and a light washing agent. Background technique [0002] With the development of industry, there are different degrees of heavy metal pollution in the soil of various countries in the world. On average, 15 million tons of Mn, 5 million tons of Pb, 3.4 million tons of Cu, 1 million tons of Ni, and 15,000 tons of Hg are discharged every year in the world. According to the national survey of sewage irrigation areas conducted by the Ministry of Agriculture of my country, in about 1.4 million hm 2 Among the sewage-irrigated districts, the land area polluted by heavy metals accounted for 64.8% of the sewage-irrigated districts, of which 46.7% were lightly polluted, 9.7% were moderately polluted, and 8.4% were seriously polluted. The area of ​​cultivated land polluted by...

AI Technical Summary

Problems solved by technology

The first method can temporarily reduce the toxicity of heavy metals, but it cannot completely remove heavy metals in the soil, which is likely to cause secondary pollution of the soil, and the repair cost is relatively expensive

The second method is a green restoration technology discovered by scientists after years of exploration and practice. It will not damage the physical and chemical properties of the soil and will not cause secondary pollution. However, simple phytoremediation generally takes 3 years, and Agricultural production must be interrupted

There is currently no low-cost, rapid in-situ remediation method for heavy metal-contaminated soils that does not interrupt agricultural production and can generate revenue

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