CN109317512A

CN109317512A - A kind of method that EDTA strengthens asparagus remediating lead-contaminated soil

Info

Publication number: CN109317512A
Application number: CN201811145304.1A
Authority: CN
Inventors: 刘建国; 刘远康; 储凯强
Original assignee: Changzhou University
Current assignee: Changzhou University
Priority date: 2018-09-29
Filing date: 2018-09-29
Publication date: 2019-02-12

Abstract

The present invention relates to a kind of methods that EDTA strengthens asparagus remediating lead-contaminated soil, belong to remediation of heavy metal-contaminated soil.It is characterized in that: (1) EDTA amount of application is 1.5g/kg soil, method of administration is to apply in two times, i.e., the 10th day after planting, the 20th day each total amount of application of Shi 50%；(2) repairing with plant is hay bamboo shoot；(3) planting density is 100 plants/m²；(4) 50 days disposable harvests after planting, whole plant is uprooped, can carry out next round phytoremediation as needed.In severe P in soil b contaminated areas (P in soil b content 300mg/kg, reach 3 times or more of edible rapid test paper P in soil b prohibitive content), by 4 wheels, about 200 days phytoremediations, the Pb content of soil can be reduced to and meet China and eat rapid test paper soil quality standard (P in soil b concentration < 80mg/kg).

Description

A kind of method that EDTA strengthens asparagus remediating lead-contaminated soil

Technical field

The present invention is a kind of method that EDTA strengthens asparagus remediating lead-contaminated soil, belongs to heavy-metal contaminated soil and repairs skill Art.

Background technique

In various heavy metal contaminants, lead (Pb) is paid high attention to, because Pb is widely used, it has also become contaminated area Maximum metallic element.On earth, almost can not find not is history by the Pb content in the place polluted Pb or even arctic ice sheet 10-100 times of preceding ice sheet Pb content, and the Pb content of South Pole ice sheet is 10 times higher than arctic ice sheet.

Excessive Pb is a variety of to the nervous centralis of human body, red blood cell, kidney, angiocarpy and the reproductive system of men and women etc. The toxic effect of organ.Long term test show the gestational period and infancy contact relatively low-dose Pb (blood Pb concentration be 10-20 μ G/dl), irreversible, untreatable and adjoint lifelong damage can be caused to the central nervous system of children, lead to children's intelligence Power decline reacts slow and absent minded etc..It was found that 24 months big child's blood Pb contents are higher, when to 10 one full year of life still Show amentia.Due to the murder by poisoning of Pb, can be measured when amentia that 7 years old when shows was by 18 years old.Recent study concentrates on The Pb of low dosage to the toxicity of people, have previously been thought that safe dosage there may be the murder by poisoning of no clinical symptoms, it is referred to as " subclinical Toxicity ", if intelligence declines, nerve conduction velocity is reduced, and ferroheme synthesis is reduced, uric acid excretion exception etc..International cancer research Pb has been classified as to the possible carcinogenic substance of the mankind by mechanism (International Agency for Research on Cancer) Matter.

China industrial and mining area and developed area, with the fast development of the increase of the size of population, industry and traffic, A large amount of applications of agricultural chemicals, the heavy metal pollution of agricultural land soil are on the rise.China digs up mine to 20 many places, smelts and work The investigation of industry contaminated wastewater point shows that the farmland Pb pollution in some areas is very serious, and area and degree are in rising trend, this The rice Pb content of a little contaminated areas reaches 0.5-3.0mg/kg, all more than state health standards.According to East China Normal University's geography System is studied, and Pb content exceeding standard rate is up to 43.2% in Chongming Island both sides of highway vegetable sample.The research of Nanjing Institute of Environmental Science Show Shanghai-Nanjing Expressway two sides away within the scope of 250 meters of road shoulder, soil and wheat are polluted by different degrees of Pb, soil Middle Pb pollution index maximum is up to 3.26, and Pb content exceeding standard rate is up to 99% in both sides of highway wheat seed.Chinese Academy of Sciences Nanjing Soil Jiangsu Province's grain (rice, wheat, flour) Pb content exceeding standard rate, which is, to be shown to the sampling Detection in 8 city of Jiangsu Province, 28 county 21.4%, some areas exceeding standard rate is up to 66%.According to the investigation of Changsha agricultural modernization institute of Chinese Academy of Sciences 1986-1988, lake The main industrial and mining area paddy soil Pb content of Nan Sheng is 52-1021mg/kg, and the background value than similar parent material development soil is 0.6-37 high Times.According to various regions sample investigation, the cities industrial area such as Beijing, Shanghai, Shenyang, Guangzhou, Nanjing and contaminated area, blood of children Pb average value are general All over 10 μ g/dl are higher than, some areas are up to 30 μ g/dl.

It was found that the Pb in food plant is the important sources of Pb in human body.In heavy metal pollution area, the Pb of human body intake There is 50-90% from food, wherein the overwhelming majority derives from grain and vegetables.Therefore, the Pb pollution problem of agricultural land soil by To highest attention.

It is intracorporal much studies have shown that some plants have extremely strong accumulation ability to the heavy metal in contaminated soil Heavy metal concentration up in its soil for growth heavy metal concentration it is hundreds of, even thousands of times.Therefore these plants are repairing a huge sum of money It has broad application prospects in terms of belonging to contaminated soil.The phytoremediation technology of heavy-metal contaminated soil is a kind of raw using nature Long plant cultivates plant by genetic engineering come the general name of restoration of soil polluted by heavy metal.It mainly include plant stability skill Art and plant extraction technology.Plant extraction technology is also referred to as plants enriched technology, it, which refers to, absorbs one using obligate root system of plant Kind or several heavy metal species, and shifted, be stored to aerial part, cauline leaf is then harvested, is focused on, thus can be fundamentally Remove the heavy metal in soil.This seminar early-stage study show wetland plant asparagus to lead in soil have it is very strong absorption and Accumulation ability can be used as the desirable plants of rehabilitating soil lead contamination.

Ethylenediamine tetra-acetic acid (EDTA) is a kind of common metal-chelator, has chelation with various heavy.It is some Research thinks that the mobility of heavy metal in soil can be improved in EDTA, and other researchs hold a different view.The present invention is applying On the basis of people studies for many years, a kind of method of EDTA reinforcing asparagus remediating lead-contaminated soil is disclosed.

Summary of the invention

The technical problems to be solved by the present invention are: a kind of method of EDTA reinforcing asparagus remediating lead-contaminated soil is provided, In lead-contaminated soil (P in soil b concentration 300mg/kg reaches 3 times or more of edible rapid test paper P in soil b prohibitive content, Belong to serious pollution), it is repaired by 4 wheels, the Pb content of soil can be reduced to and meet the edible rapid test paper soil matter in China Amount standard (P in soil b concentration < 80mg/kg) (referring to attached drawing 1).

The technical solution adopted by the present invention to solve the technical problems is: a kind of EDTA reinforcing asparagus remediating lead-contaminated soil Method, it is characterized in that: (1) EDTA amount of application be 1.5g/kg soil, method of administration be apply in two times, i.e., in planting The 10th day afterwards, the 20th day each total amount of application of Shi 50%；(2) repairing with plant is hay bamboo shoot；(3) planting density be 100 plants/ m²；(4) plant harvest period and harvesting method: 50 days disposable harvests after planting are uprooped whole plant, so After focus on.Smooth soil after plant harvest can carry out next round phytoremediation as needed；It (5), will be native when EDTA is applied Earth is poured water to shoaling layer (about 3cm), is allowed water layer to fall dry rear (water layer disappearance) naturally after application and is poured water again to shoaling layer (about 3cm), So repeat, until plant harvest.

The beneficial effects of the present invention are: in P in soil b contaminated areas, (P in soil b content 300mg/kg, reaches edible agricultural product 3 times or more of Producing Area Soil Pb prohibitive content belong to serious pollution), it, can be significantly by 4 wheels, about 200 days phytoremediations Reduce the Pb content of soil.By the implementation of this application art solutions, the Pb content of soil can be reduced to and meet me State eats rapid test paper soil quality standard (P in soil b content < 80mg/kg) (referring to attached drawing 1).

Detailed description of the invention

The Content of Pb in Soil of Fig. 1 difference reparation number

Specific embodiment

Embodiment 1: a kind of method that EDTA strengthens asparagus remediating lead-contaminated soil.Specific embodiment are as follows: (1) EDTA is applied Dosage is 1.5g/kg soil, and method of administration is to apply in two times, i.e., the 10th day after planting, the 20th day each Shi always apply 50% (being shown in Table 1) of amount；(2) repairing with plant is hay bamboo shoot；(3) planting density is 100 plants/m²；(4) plant harvest period And harvesting method: whole plant is uprooped, is then focused on by 50 days disposable harvests after planting.Plant is received Rear smooth soil is obtained, next round phytoremediation can be carried out as needed；(5) when EDTA is applied, soil is poured water to shoaling layer (about 3cm), it allows water layer to fall dry rear (water layer disappearance) naturally after application to be poured water again to shoaling layer (about 3cm), so repeat, until Plant harvest.

Uptake (mg/ plant) of the asparagus to lead in soil under 1 difference EDTA amount of application of table and method of administration

Note: applied once is to press amount of application one-time use in the 10th day after planting；Application is in plant in two times The 10th day after plantation, the 20th day each total amount of application of Shi 50%；In three times application for the 10th day after planting, the 20th day, The 1/3 of 30th day each total amount of application of Shi.

Data proves in table 1, is 1.5g/kg soil, using the method for administration applied in two times in EDTA amount of application When, the amount of plant absorption Pb nearly reaches peak；When EDTA amount of application is 2.0,2.5g/kg soil, plant absorption Pb's Amount only has micro increase, should not select from economic benefit angle.Data proves in attached drawing 1, and the present embodiment can be significantly Reduce P in soil b content.It is that (serious pollution degree reaches edible agricultural product and produces 300mg/kg that data, which are in P in soil b concentration, in figure 3 times or more of ground P in soil b prohibitive content) under the conditions of obtain.Pass through the wheel of this application art solutions 4, about 200 days realities Apply, the Pb content of soil can be reduced to meet China eat rapid test paper soil quality standard (P in soil b concentration < 80mg/kg)。

Claims

1. a kind of method that EDTA strengthens asparagus remediating lead-contaminated soil, it is characterized in that: (1) EDTA amount of application is 1.5g/kg soil Earth, method of administration are to apply in two times, i.e., the 10th day after planting, the 20th day each total amount of application of Shi 50%；It repairs and uses Plant is hay bamboo shoot, and planting density is 100 plants/m²。