The invention discloses a method for improving capacity of descendants of Solanum nigrum to remedy cadmium-contaminated orchid soil by grafting and belongs to the field of remediation of environmental heavy metal contamination The method includes the steps of when five true leaves of a tomato plant expand, cutting off 2+/-02cm long stem tips as rootstocks, selecting stem tips of a cadmium-hyper-accumulated Solanum nigrum seedling with 7 true leaves expanding, as scions 3+/-02cm long, grafting the stem tips of the Solanum nigrum seedling to the rootstocks of the tomato plant by cleft grafting, and collecting seeds after the seeds of the Solanum nigrum are ripe; raising seedlings in spring, directly transplanting grafted descendant seedlings of the Solanum nigrum with three tree leaves expanding into cadmium-contaminated orchid soil, irrigating to ensure 80% of moisture holding capacity of field soil, and performing daily management; after 60 days when the grafted descendants of the Solanum nigrum are in the full-blossom stage, harvesting overground parts of the grafted descendants The grafted descendants of the Solanum nigrum employing the tomato rootstocks allow cadmium extraction pear unit area to be increased; the cadmium extraction is 930% higher than that achieved by the un-grafted Solanum nigrum The method has the advantages that the cost is low, operability is high, the method is environment friendly, and the capacity of the Solanum nigrum to remedy the cadmium-contaminated orchid soil

Method for improving capacity of descendants of Solanum nigrum to remedy cadmium-contaminated orchid soil by grafting

The invention discloses a method for treating heavy metal contaminated soil. The method comprises the steps of breaking a heavy metal contaminated paddy field, irrigating the paddy field until a water logging layer on a soil layer is 10-15cm deep after breaking the 0.5-0.6m deep soil on the surface layer into soil lumps with sizes less than 2-3mm, adding a modified clay mineral adsorbent, mechanically stirring the adsorbent, standing for 6-8 hours, removing the supernatant, and carrying out solid-liquid separation; then uniformly adding magnetic nano materials to the soil with adjusted moisture content, mechanically stirring the materials, standing for 3-8 hours, and collecting the magnetic nano materials in the soil by way of magnetic separation, thus achieving solid-solid separation; preparing leachate for leaching, adding carbon microspheres while leaching, and then, leaching 1-3 times by using pure water as an eluent, thus obtaining the treated soil, wherein the amount of water used each time is 0.6-1 times the leachate added for the first time by volume. The method is simple to operate, is low in cost, has high removal efficiency, meets the actual requirements, and has good popularization and application values.

Method for treating heavy metal contaminated soil

The invention relates to a leaching device used in vertical transfer of pollutants in soil. The leaching device comprises a spray nozzle, a water flow meter, a leaching column for holding an experimental earth pillar and a percolate accommodating container, wherein, the leaching column is internally provided with at least two filter layers capable of filtering leaching liquid, a filter layer structure is respectively arranged on the upper and lower ends of the experimental earth pillar, and each filter layer is provided with a filter screen layer, a filter bulb layer and a filter paper layer; and in addition, the height of the leaching column body is 90cm-150cm, and the inner diameter of the cross section of the column body is 5cm-15cm. The leaching device has the advantages that on the basis of the large axial size of the leaching column, vertical transfer of the pollutants in the profile of the deeper soil can be simulated; by setting the water flow meter, the flow velocity and flow rate of injection water can be accurately controlled; by setting the upper filter layer, the injection water can be uniformly sprayed; and by setting the lower filter layer, the filter effect can be ensured and percolate can be timely and effectively discharged.

Leaching device used in vertical transfer of pollutants in soil

The invention discloses a reaction device for simulating migration and transformation of a soil organic pollutant, relates to a reaction device, and solves the problem that existing leaching experiment equipment for simulating the migration and transformation of the soil organic pollutant is large in experimental error, low in equipment use ratio and poor in adaptability The reaction device comprises a first water box, a second water box, a water pump, a water inlet pipe, a steady flow pipe, a support, a supporting frame, a base, a fixed plate, a first regulating valve, a second regulating valve, multiple flowmeters, multiple sieve hole plates, multiple earth pillars and multiple fifth regulating valves, wherein the first water box, the support and the supporting frame are all arranged on the base; the fixed plate is connected with the supporting frame, and the second water box is supported through the supporting frame; the supporting frame is provided with the multiple earth pillars which are vertically arranged, each flowmeter is arranged right above each earth pillar, the multiple flowmeters are fixedly arranged on the fixed plate, and the sieve hole plates are fixedly arranged on the support. The reaction device disclosed by the invention is used for simulating the migration and transformation of the soil organic pollutant.

Reaction device for simulating migration and transformation of soil organic pollutant

The invention relates to a method for comprehensively utilizing low-concentration heavy metal-containing soil improvement and repairing damaged soil by plants after detoxification of a contaminated field The method comprises the following steps of: conveying of low-concentration soil after heavy metal-containing soil is detoxified, sludge and pulverized fuel ash; principal fermentation, mixing of various ingredients; primary fermentation; static state of post-fermentation (secondary fermentation); uniform turning (aerobic and anaerobic) fermentation; conveying of improved soil; and vegetation repairing (woody and herbaceous plants) planting for the contaminated soil In the method, a modifier is added for modification, so that the content of heavy metals in the soil is reduced, the structure and pores of the damaged soil are repaired, and the permeation and air permeability of the soil are improved; and organic matters and other noxious matters in sludge and soil are decomposed and degraded in a certain condition by utilizing microbes in the sludge to reduce volume weight and compactness, so that the improved soil forms a substance similar to humus soil to serve as a biochemical process of the improved soil and fertilizer According to the method, the planted vegetation growing environment of the land which uses the improved soil as a soil base material is ensured, so that the waste is used to treat waste, and the comprehensive utilization is improved

Method for comprehensively utilizing low-concentration heavy metal-containing soil improvement and repairing damaged soil by plants after detoxification of contaminated field

The utility model relates to a leaching device for transfer and conversion of pollutants in soil. The leaching device is characterized in that a leaching box is installed on a base bracket; a leaching box cover is arranged at the upper part of the leaching box; a ventilation hole and a liquid inlet are formed on the leaching box cover; a plate type nozzle is installed at the lower part of the liquid inlet; one end of a silicone tube stretches into a liquid storage bottle, and the other end of the silicone tube is connected with the liquid inlet formed on the leaching box cover through a peristaltic pump; a plurality of sampling ports are formed on a box body of the leaching box in the horizontal direction and in the vertical direction, and soil solution samplers are inserted in the sampling ports; a leachate filter is installed at the bottom of the leaching box; and a polyvinyl chloride pipe is connected with the bottom end of the leachate filter and is connected with a leachate receiving bottle through the silicone tube. The leaching device can sample and detect leaching liquid in the horizontal direction and in the vertical direction in real time, and is characterized by small workload and good reproducibility, and is simply and conveniently operated and accurately controlled.

Leaching device for transfer and conversion of pollutants in soil

The invention relates to an agricultural method for recovering cadmium pollution farmland soil, comprising the following steps of: 1. recovering the cadmium pollution soil by nightshades; 2. recovering the cadmium pollution soil by Beta vulgaris var.cicla L, wherein the asarum exact of the invention has the advantages of high efficiency and low residual and is harmonious with the environment and other living beings; and 3. testing the total cadmium removal amount of the nightshade plants and Beta vulgaris var.cicla L plants. The invention not only can continuously remove heavy metals in the soil for a long time but also can ensure that the biomass is not reduced and prevents plant diseases and insect pests from increasing.

Agricultural method for recovering cadmium pollution farmland soil

The invention discloses a method for restoring slight and medium cadmium polluted soil by maize-capsicum intercropping, and relates to a polluted soil restoring method. Capsicum and maize with a genetic relationship are simultaneously planted in an intercropping mode, 2-6 rows of capsicum and 2 rows of maize are distributed in a field, the variety of the capsicum is mitaka pod pepper, and the variety of the maize is nugget honey. Field management and fertilization of crops are performed according to a single cropping method for the capsicum and the maize. The maize is harvested when the maize is ripe, and the capsicum is harvested when the capsicum is red. The cadmium content of the maize is reduced to a national regulated safe eating standard. The capsicum is used for extracting capsaicin and capsanthin for industries such as medical treatment, military affairs and cosmetics. Growth of the capsicum is promoted by maize-capsicum intercropping, the capsicum takes away a large amount of heavy metal from soil and is used for the non-food industry, the content of the heavy metal in the vegetable soil is reduced, and safety of agricultural products is guaranteed.

Method for restoring slight and medium cadmium polluted soil by maize-capsicum intercropping

The invention relates to a preparation method of polluted soil remediation liquids and in particular to a method for preparing an eluent in remediation of heavy metal polluted soil. The method comprises the following steps: (1), preparing sodium melamine hexa-acetate by one-step water-bath heating method using sodium iminodiacetate, sodium bicarbonate and cyanuric chloride as synthesis raw material and water as solvent, then acidifying with hydrochloric acid to obtain melamine hexa-acetate, and primarily washing and then filtering to obtain melamine hexa-acetate; (2), weighing melamine hexa-acetate and dissolving melamine hexa-acetate in distilled water to make an eluent; and (3), weighing a sample of heavy metal polluted soil, adding the eluent into the sample, then loading to an oscillator for oscillation followed by centrifugal separation, and detecting the sample which is weighed and then added with the eluent, followed by centrifugal separation or filtration separation. The method can effectively remove heavy metal pollutants from the heavy metal polluted soil, is favorable to the reduction in processing cost of polluted soil, and provides a technical support for recycling of heavy metal polluted soil.

Method for preparing eluent in remediation of heavy metal polluted soil

The invention provides a method for overcoming vegetable crop continuous cropping obstacles in a facility, and relates to a vegetable crop method. The method includes the steps of composting field crop corn straw and cow dung according to the ratio of 1:1-5:1 before vegetable crop sowing or transplanting, applying the mixture in continuous cropping soil according to the input of 1000-5000 kilograms per mu, conducting tillage and ridging, evenly putting Baijing pheretima tschiliensis in the continuous cropping soil according to the input of 5000-6000 Baijing pheretima tschiliensis per mu, regulating temperature and humidity, and exercising the survivability of silkworms in the continuous cropping soil, wherein after survival exercise of silkworms, the soil is covered with a degradable plastic film, sowing or crop transplanting is conducted, and normal filed management is conducted. By means of the method, ridging and film mulching are conducted in a vegetable land through the degradable plastic film, moisture preservation is conducted, it is avoided that aboveground parts have adverse effects on silkworms in the soil during dry spraying, and the method is a composite method for effectively overcoming vegetable crop continuous cropping obstacles in the facility.

Yang Jisong

Papers

Leaching device for transfer and conversion of pollutants in soil

Agricultural method for recovering cadmium pollution farmland soil

Method for restoring slight and medium cadmium polluted soil by maize-capsicum intercropping

Method for preparing eluent in remediation of heavy metal polluted soil

Method for overcoming vegetable crop continuous cropping obstacles in facility