Microorganism/animal and plant combined ecological restoration method for farmland soil cadmium pollution

Abstract

The invention relates to a microorganism / animal and plant combined ecological restoration method for farmland soil cadmium pollution. The method comprises the following steps: introducing cultured adult earthworms into farmland cadmium polluted soil, and adding crushed fine baits; introducing cadmium-resistant fungi one month before sexual maturity of adult earthworms while sowing ryegrass; harvesting the aboveground part of the ryegrass, and treating; and arranging a plastic greenhouse constant-temperature humidity control device for farmland remediation soil, controlling the indoor temperature of a greenhouse to be 15-20 DEG C, and keeping the soil humidity to be 20-30%. The method has the advantages that adult earthworms can resist 1.5-2.4 mg / kg of cadmium pollution, improve the soil fertility and porosity, promote the breeding of cadmium-resistant fungi and facilitate the root development of ryegrass; the cadmium-tolerant fungi can slow down the toxic action of cadmium pollution onindigenous microorganisms and plants and enhance the transfer of cadmium ions to the roots of ryegrass; and the ryegrass enriching soil cadmium pollution is treated to permanently remove cadmium. Themethod is low in investment, ecological, environment-friendly, safe, harmless and effective for a long time.

Description

technical field [0001] The invention relates to the technical field of soil remediation, in particular to a microorganism / animal and plant combined ecological restoration method for cadmium-polluted farmland soil. Background technique [0002] Heavy metals are difficult to degrade, highly toxic, and accumulate in soil. The toxicity of enriched heavy metal elements can hinder the normal life activities of microorganisms, animals and plants, destroy the physical and chemical properties of soil, and eventually reduce soil fertility and affect the growth of crops. Heavy metal pollution in farmland soil can pose a threat to human health in the following ways. First, the absorption of excessively enriched heavy metals by agricultural products makes the heavy metals in crops exceed the standard. The intake of such crops will cause serious damage to human health; secondly, the heavy metal particles in the soil enter the air, Enter the human body through skin contact, inhalation, and...

AI Technical Summary

Problems solved by technology

Soil leaching is the process of using fluid to remove soil pollutants. With the aid of a leaching agent that can promote the dissolution or migration of pollutants in the soil environment, the leaching agent is pushed through the hydraulic pressure head, injected into the polluted soil layer, and then The leachate containing pollutants is extracted from the soil layer, and the addition of the eluent has the risk of destroying the physical and chemical properties of the soil and the structure of the microbial community, and different types of contaminated soil need to be treated in the early stage, and the process is diverse Complicated; in-situ thermal desorption technology using heat conduction (electric heating, gas heating) technology and resistance heating technology in heat treatment technology has been implemented in China one after another, but when applied to large-scale farmland soil, its energy supply is limited and consumes a lot of electricity. Gas resources; in-situ reduction technology has been further verified in chlorinated hydrocarbon-contaminated sites and hexavalent chromium-contaminated sites

[0005] Phytoremediation has carried out a number of demonstration applications in the field of farmland and mine treatment. It is regarded as the green and sustainable restoration technology with the most development potential in the next 5 to 10 years. The single use of plants to control soil heavy metal pollution has limited effect, so it is urgent to create multiple The combined ecological restoration method improves the ecological environment and restoration effect, and effectively replaces physical / chemical restoration techniques that damage the ecological environment and cause secondary pollution

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