CN106670219A

CN106670219A - Method for enhancing phytoremediation for cadmium pollution in soil

Info

Publication number: CN106670219A
Application number: CN201710007540.6A
Authority: CN
Inventors: 贺前锋; 秦华; 刘代欢; 邓林
Original assignee: HUNAN YONKER ENVIRONMENTAL PROTECTION RESEARCH INSTITUTE Co Ltd
Current assignee: HUNAN YONKER ENVIRONMENTAL PROTECTION RESEARCH INSTITUTE Co Ltd
Priority date: 2017-01-05
Filing date: 2017-01-05
Publication date: 2017-05-17

Abstract

The invention discloses a method for enhancing phytoremediation for cadmium pollution in soil. According to the method, hyperaccumulators are planted in the soil with the cadmium pollution, and then an additive is poured in the soil with the cadmium pollution, wherein the additive is the solution of ethylenediaminetetraacetic acid (EDTA) and/or indole-3-acetic acid (IAA). According to the method disclosed by the invention, with the adoption of the method of applying the EDTA and IAA, the multiple action of the EDTA and IAA is adequately exerted, the defects of low plant biomass, low growth speed, long remediation period and the like in the phytoremediation for the Cd pollution are solved, the accumulation of Cd in plant bodies is improved, the toxic action of heavy metals on plants is reduced, and a great application value is achieved.

Description

A kind of method of fortification of plants rehabilitating soil cadmium pollution

Technical field

The present invention relates to a kind of method of fortification of plants rehabilitating soil cadmium pollution, belongs to heavy-metal contaminated soil reparation neck Domain.

Background technology

Since the industrial revolution, stage of China's economy in developing rapidly, while also bringing substantial amounts of environmental problem, work The unreasonable administration of the discharge of industry solid waste, the irrigation of pollutant effluents, pesticide and chemical fertilizer and atmospheric sedimentation etc. can be led Cause substantial amounts of heavy metal to enter in soil, seriously threaten the health of ecological environment of soil and human body.Report according to the relevent statistics, China is wide by the soil erosion of heavy metal pollution, and pollution concentration is high, and soil suffers from heavy damage, wherein arable land is by a huge sum of money Category pollution soil types the most serious, to reach 20,000,000 hectares, area accounts for the 1/5 of total area under cultivation to contaminated area. 2007, Pan Genxing et al. was had found by being sampled investigation to the regional rice heavy metal cadmium content in 6, the whole nation, in selective examination sample The exceeded rice of cadmium content accounts for 10%；Separately data show, cultivated area nearly 1.33 ten thousand hm of the China by Cd pollutions², it is related to 11 save 25 areas；Japan is also because cadmium pollution has caused " Itai-itai diseases ".Therefore, solve Cadmium Pollution in Soils environmental problem to compel The eyebrows and eyelashes.

At present, the restorative procedure of Cd Pollution in Soil is varied, and technology is also more ripe, is broadly divided into physical chemistry reparation Method and phytoremediation, wherein physical chemistry repairing method are mainly digged including soil moved in improve the original, soil removal and replacement, deep ploughing, electrokinetic process, chemical leaching With chemosetting etc., but these physical chemistry recovery techniques not only high cost, take effect slow but also easily produce secondary pollution, it is right The environmental destruction of soil is larger, therefore is difficult to be widely used in repairing and administering Cadmium Pollution in Soils environmental problem.Plant Recovery technique is to be resistant to and surpassed based on plant accumulate based on certain or the ability of some heavy metal elements, by plant absorption Harvested after heavy metal, and dealt carefully with, you can the heavy-metal movement is gone out into soil, reached pollution control and restoration of the ecosystem Purpose a kind of environmental pollution treatment technology.Phytoremediation is invested low cost on Cd Pollution in Soil is administered, is repaired due to it Effect is good and non-secondary pollution so that it becomes study hotspot and the emphasis that this area heavy metal-polluted soil is repaired.And super enrichment Plant is then the research emphasis of phytoremediation, although super enriching plant heavy metal has good enrichment, due to it Biomass is low, causes the application of phytoremediation technology to obtain a certain degree of restriction the features such as repairing efficiency is long.

In recent years, a large amount of scholars have found that addition chelating agen can improve activity of the heavy metal in soil, promote by studying Enter accumulation of the heavy metal-polluted soil in plant body, conventional chelating agen has EDTA, EDDS, NTA, CA etc., and research shows：EDTA pair The activation capacity of Cd is most strong in soil, but the EDTA of addition excessively can produce toxic action to plant, while the EDTA meetings of remnants Secondary pollution is produced to environment.Also studies have found that, adding phytohormone can be conducive to the growth of plant, improve the life of plant Thing amount, while the toxic action of heavy metal on plants can also be alleviated, shortens the phytoremediation cycle, but the phytohormone of excessive addition There can be certain inhibition to the growth of plant, conventional phytohormone has IAA, GA, CTK, ABA etc..Therefore one is worked out Plant the Biomass that can be improved the repairing effect of plant and can increase plant again simultaneously, the method in the cycle for reducing phytoremediation just to show Obtain particularly important.

The content of the invention

It is an object of the invention to provide a kind of method of fortification of plants cadmium pollution soil repair, gives full play to chelating agen work Change the synergism that heavy metal-polluted soil and phytohormone improve phytomass, it is intended to solve that phytomass is low and repairing efficiency Long the problems such as, improves the repairing effect of plant simultaneously, is that a kind of rehabilitation cost is low, repairing effect is good and environmentally friendly and nothing two The restorative procedure of secondary contaminated soil heavy metal Cd.

The technical scheme is that, there is provided a kind of method of fortification of plants rehabilitating soil cadmium pollution, in cadmium pollution soil Middle plantation super enriching plant, and additive is added in backward cadmium pollution soil, the additive is ethylenediaminetetraacetic acid (EDTA) And/or the solution of indole-3-acetic acid (IAA).

Further, the super enriching plant is with ore deposit Herba hylotelephii erythrosticti.

Further, the additivated time is thrown in cadmium pollution soil for 10-15 days before super enriching plant harvesting.

Further, the dosage of the ethylenediaminetetraacetic acid is 100-400kg/ mus.

Further, the dosage of the indole-3-acetic acid is 0.3-3kg/ mus.

Further, the additive is 25-100mmol/L ethylenediaminetetraacetic acid and 0.1-1mmol/L indole-3-acetic acids Aqueous solution.

Further, the seedling of the super enriching plant is first, using Solution culture method, to treat that super enriching plant root grows It is transplanted in cadmium pollution soil after root system.

Further, the pH value of the nutritional solution is 5.2-5.8, and the concrete composition of nutritional solution is：2.0mmol/L Ca (NO₃)₂·4H₂O、0.7mmol/L K₂SO₄、0.5mmol/L MgSO₄·7H₂O、0.1mmol/L KCl、0.1mmol/L KH₂PO₄、100μmol/L FeSO₄·7H₂O、1.0μmol/L ZnSO₄。

Compared with prior art, beneficial effects of the present invention are as follows：

(1) present invention has cost of investment using plant soil restoration Cd pollutions compared to other physical chemistry repairing methods The advantages of low, repairing effect is good, simple to operate, impact to environment is little.

(2) the chelating agen EDTA that uses of the present invention has good activation to the Cd in soil, can be larger carry The effect of high plant Adsorption of Heavy Metals Cd.

(3) the phytohormone IAA that the present invention is used can not only improve the Biomass of plant, while heavy metal can also be slowed down Toxic actions of the Cd to plant.

(4) present invention has given full play to the multiple action of EDTA and IAA by the method using EDTA and IAA is applied, and solves Phytomass of having determined is little, the speed of growth is slow and the defect of the phytoremediation Cd pollution such as repairing efficiency length, while improve Cd Accumulation in plant body, reduces the toxic action of heavy metal on plants, with good using value.

Description of the drawings

Impact under Fig. 1 different tests treatment conditions to Cadmium in Soil content.

Specific embodiment

With reference to embodiment, the invention will be further described.

Embodiment

This pot experiment region is located at Changsha, Hunan Liuyang economic development zone Yongqing environmental protection company experiment interior, this Area belongs to subtropical zones monsoon moist climate, makes a clear distinction between the four seasons, with sufficient sunshine-duration and rainwater, many average temperatures of the whole year 17.5 DEG C, annual rainfall is about 1200 millimeters, year sunshine it is total when number be about 2000 hours, frost-free period in year is about 240 days or so.This basin The farmland topsoil (0-20cm) that test soil is picked up near heavy metal smeltery of Hunan Province is planted, soil types belongs to reddish brown Earth, soil sample removes the plant and stone remained in soil Jing after natural air drying, and 100 mesh plastic screens are crossed after grinding, and measures its basic Physicochemical property is：PH value is 5.38, and organic matter is 18.62g/kg, and full phosphorus is 0.53g/kg, and full nitrogen is 3.08g/kg, and full Cd is 3.19mg/kg。

Cutting propagation, the basically identical companion's ore deposit Herba hylotelephii erythrosticti branch of selected shape size, the companion's ore deposit that will be chosen are adopted with ore deposit Herba hylotelephii erythrosticti Herba hylotelephii erythrosticti branch is put in nutritional solution and cultivates, and is transplanted to after plant root grows the vigorous root system of comparison in root bag soil, per basin 3 Strain, and supply growth and development of plants, base manure to adopt KH while applying a certain amount of base manure₂PO₄And NH₄(SO₄)₂Two kinds of reagent mixing add Plus, wherein, three kinds of thes concentrating of nutrients of N P and K are respectively 100mg/kg, 80mg/kg and 100mg/kg.

Cross afterwards 10 mesh sieves for trying air-dried the grinding of soil Jing, pot experiment is put into 2kg soil per basin.In growing process It is every to need to be adjusted potted plant position at regular intervals to ensure that plant is subject to uniform illumination and moisture sufficient, while Want the normal variable intervals of Jing to pot water, it is ensured that it is potted plant in moisture content for field capacity 70% or so.

The growth cycle of planting plants is 100 days, after plant maturation, its aerial parts and under ground portion is adopted respectively Sample, adopts the plant sample returned and is cleaned up with tap water, then is cleaned with distilled water and deionized water.Plant sample is dried, is put Complete 30min at 105 DEG C, dries to constant weight at a temperature of 70 DEG C, claims its weight, and pulverization process is being carried out to plant, fills Bag is to be measured.

It is described further below in conjunction with concrete scheme.

Scheme one：

In plant maturation first 10 days are harvested to the potted plant middle EDTA for adding 25mmol/L, 50mmol/L, 100mmol/L respectively Solution, and control experiment is carried out with blank group, per group of experiment is repeated 3 times.

Table 1 is the impact under the process of difference EDTA concentration to aboveground vegetation part Biomass and Adsorption of Heavy Metals

For blank group, to certain density EDTA is added in potted plant aboveground vegetation part can be significantly changed Biomass, the content of aboveground vegetation part Cd and aboveground vegetation part Cd absorbtivitys and remediation efficiency.Wherein add 50mmol/ The EDTA of L is optimal to the repairing effect of soil Cd, adds the EDTA of 100mmol/L and can improve the Cd of aboveground vegetation part and contains Amount, but the Biomass of plant can be reduced, so as to reduce remediation efficiency of the plant to soil Cd.

Scheme two：

In plant maturation first 10 days are harvested to the potted plant middle IAA for adding 0.1mmol/L, 0.5mmol/L, 1mmol/L respectively, And control experiment is carried out with blank group, per group of experiment is repeated 3 times.

Table 2 is the impact under the process of difference IAA concentration to aboveground vegetation part Biomass and Adsorption of Heavy Metals

For blank group, middle certain density phytohormone IAA is added significantly to improve plant to potted plant Biomass, while also can accumulations of a certain degree of increase Cd in plant body, wherein to potted plant middle addition 0.5mmol/L's IAA is optimal to the adsorption effect of Cd in soil to the growth of plant and plant.But the IAA to potted plant middle addition 1mmol/L then can The Biomass of plant is set to reduce while can also affect absorption of the plant to Cd, therefore the IAA of high concentration can a certain degree of obstruction The growth of plant and the effect of rehabilitating soil Cd.

Scheme three：

Plant maturation harvest first 10 days IAA to potted plant middle EDTA, 0.5mmol/L for adding 50mmol/L respectively, The solution of the IAA of the EDTA and 0.5mol/L of 50mmol/L, and control experiment is carried out with blank group, per group of experiment is repeated 3 times.

Table 3 is the impact under different additive process to aboveground vegetation part Biomass and Adsorption of Heavy Metals

For blank group (CK), middle add the solution of certain density EDTA, IAA and EDTA+IAA equal to potted plant The adsorption efficiency of the Biomass, the enriching quantity of aboveground vegetation part Cd and soil Cd of plant can be significantly improved.Wherein in potted plant The best results of the aggregate sample of the IAA of the EDTA and 0.5mmol/L of 50mmol/L are added, repairing effect is up to 39.97%.

Claims

1. a kind of method of fortification of plants rehabilitating soil cadmium pollution, it is characterised in that plant super enrichment in cadmium pollution soil and plant Thing, and additive is added in backward cadmium pollution soil, the additive is the molten of ethylenediaminetetraacetic acid and/or indole-3-acetic acid Liquid.

2. the method for claim 1, it is characterised in that the super enriching plant is with ore deposit Herba hylotelephii erythrosticti.

3. the method for claim 1, it is characterised in that the additivated time is thrown in cadmium pollution soil for super enrichment 10-15 days before plant harvesting.

4. the method for claim 1, it is characterised in that the dosage of the ethylenediaminetetraacetic acid is 100-400 kg/ Mu.

5. the method for claim 1, it is characterised in that the dosage of the indole-3-acetic acid is 0.3-3 kg/ mus.

6. the method for claim 1, it is characterised in that the additive is 25-100 mmol/L ethylenediaminetetraacetic acid With the aqueous solution of 0.1-1 mmol/L indole-3-acetic acids.

7. the method for claim 1, it is characterised in that the seedling of the super enriching plant is first to adopt nutrient solution culture Support, be transplanted in cadmium pollution soil after super enriching plant root grows root system.

8. method as claimed in claim 7, it is characterised in that the pH value of the nutritional solution is 5.2-5.8.