19results about How to "Reduce cadmium content" patented technology

According to the method disclosed by the invention, arbuscular mycorrhizal fungi and biochar are added while multiple-leaf goldenrain trees are planted in cadmium-polluted soil. Compared with a traditional remediation mode of independently utilizing plants or microorganisms or biochar, the microorganism-plant-biochar combined remediation has the advantages that the plants, the microorganisms and the biochar are co-cultured to form a symbiotic system, so that the cadmium content in the soil is remarkably reduced, the remediation capacity of the plants is enhanced, and meanwhile, the growth of the plants is remarkably improved. The strategy breaks through the limitation that in the prior art, only improvement of plant resistance is concerned, and the strategy more focuses on the double effects of improving the phytoremediation capacity and promoting the growth effect, so that the maximization of the phytoremediation effect is achieved.

The invention discloses a rice selenium enrichment and cadmium reduction synergistic conditioner, the conditioner comprises selenide, a nano bamboo charcoal complexing agent, a soil pH regulating agent, an organic material and a root system oxygen secretion accelerant with different contents according to different soil types, and by adding the conditioner into soil, the soil environment is effectively improved, and the soil quality is improved. The soil PH is controlled within the range of 6.0-7.5 suitable for rice planting, the rice cadmium content is reduced, food safety is guaranteed, the rice selenium content is increased, the rice nutritional value is improved, meanwhile, the yield is increased, economic benefits are improved, and the problems that in the prior art, selenium enrichment and cadmium reduction are difficult to cooperate, and the cadmium reduction effect is unstable are solved.

The invention belongs to the technical field of heavy metal pollution treatment, and discloses a method for reducing soil cadmium activity and wheat grain cadmium content. According to the method, the low-cadmium-accumulation wheat variety is selected, the composite conditioner is applied, the low-cadmium-accumulation wheat variety is Jimai 22, and the composite conditioner is composed of mineral source potassium fulvate and zinc fertilizer. The complex passivation effect of humic acid components in mineral source potassium fulvate on soil heavy metal is utilized, the ion antagonism effect of zinc and cadmium and the low cadmium accumulation characteristic of Jimai 22 are combined, the cadmium content of wheat grains is synergistically reduced to 0.1 mg / kg or below, meanwhile, the cadmium content of the soil can be remarkably reduced, and the soil with cadmium exceeding the standard can be repaired. The treatment method provided by the invention has the advantages of simple operation, easily available raw materials, low cost, stable synergistic cadmium reduction effect and the like.

The application is the application of Spirodela and microorganisms in repairing cadmium-polluted water bodies and reducing cadmium content in cadmium-polluted paddy field rice grains. The specific steps are as follows: first, prepare Oscillospiraceae bacterial suspension, Enterobacter bacterial suspension and Pantoea bacterial suspension respectively; then mix the three kinds of bacterial suspensions in proportion to obtain a mixed bacterial suspension; then add the mixed bacterial suspension and Spirodela prepared in proportion to the cadmium-polluted water bodies to be repaired or the cadmium-polluted paddy fields to be repaired, and the Spirodela and the microorganisms form a "Spirodela-functional bacterial community" symbiotic system; the microorganisms further transport cadmium to the leaves by adsorption, transformation, leaf surface sedimentation or transpiration; finally, the Spirodela is concentrated for treatment, thereby repairing the cadmium-polluted water bodies or reducing the cadmium content in the cadmium-polluted paddy field rice grains. Through the application, the cadmium-polluted water bodies can be better repaired, and the cadmium content in the cadmium-polluted paddy field rice grains can be effectively reduced.

The invention discloses a rice cadmium-reducing foliar barrier and an application method thereof. The cadmium-reducing foliar barrier is prepared by compounding rice husk wood vinegar, sodium silicate and zinc sulfate, wherein the mass ratio is 15%-20% of sodium silicate, 10%-15% of zinc sulfate and the remainder is rice husk wood vinegar. The cadmium-reducing foliar barrier is sprayed at the tillering stage and the booting stage of rice respectively. Compared with spraying an equal amount of clear water and a rice cadmium-reducing foliar barrier of other formulas, the cadmium-reducing foliar barrier of the invention significantly reduces the cadmium content in rice brown rice, is simple to operate, and raw materials are easy to obtain, and waste is turned into treasure. Several barrier components cooperate with each other to jointly play the role of reducing cadmium in rice, and have a strong prospect for promotion and application.

The invention discloses citrobacter freundii and an application thereof. The citrobacter freundii disclosed by the invention has the functions of high cadmium resistance and improvement of selenium bioavailability, and the strain is classified and named as Citrobacter freundii DS and is preserved in CCTCC (China Center For Type Culture Collection) on May 26, 2022. The strain has high tolerance to heavy metal cadmium, can still grow under the condition that the concentration of Cd < 2 + > is 6 mM, and can reach the maximum biomass within 40 hours. When the strain is applied to cadmium-polluted soil, the proportion of exchangeable cadmium in the soil and the content of effective cadmium in the soil can be remarkably reduced, and meanwhile, the content of soluble selenium and effective selenium in the soil can be remarkably increased. A rice potting experiment is carried out, so that the cadmium biological enrichment coefficient of each part of the rice is further reduced, and the selenium biological enrichment coefficient and the selenium transfer coefficient are improved. The strain has a remarkable effect in the application of repairing cadmium pollution of soil, improving the biological utilization of selenium and promoting crop growth.

The invention belongs to the technical field of soil heavy metal remediation, and relates to an adsorbent for soil heavy metal remediation and a preparation method and application thereof. The invention provides a preparation method of an adsorbent for soil heavy metal remediation. The preparation method comprises the following steps: grinding nostoc sphaeroids kutz through liquid nitrogen, and extracting with an organic solution to obtain a nostoc sphaeroids kutz extract; dispersing the nostoc sphaeroids kutz extract, charcoal and sodium alginate in a polyethyleneimine solution to prepare a core material; and dropwise adding the core material into a calcium chloride solution to prepare the adsorbent. The adsorbent provided by the invention can realize soil heavy metal remediation, is beneficial to improvement of AMF activity and mycelial growth, improves the infection rate of AMF to rice, and reduces the content of heavy metals in rice grains. The invention aims to solve the technical problem that application of biochar to soil heavy metal remediation and agricultural safety production cannot be considered at the same time.

According to the method for reducing the cadmium content in the peanuts, the cadmium content in the peanuts is reduced by regulating and controlling the molar ratio of calcium to cadmium in a soil solution, and the molar ratio of calcium to cadmium is 20000-210000. According to the method for reducing the cadmium content in the peanuts by regulating and controlling the calcium-cadmium ratio of the soil solution, the calcium / cadmium molar concentration ratio of the soil solution is regulated and controlled to 20000-210000 by applying the calcium fertilizer, the cadmium content in the peanuts can be effectively reduced, the yield of the peanuts can be increased, the pertinence is high, and the method is scientific and accurate; the technical defect that the application amount of an existing in-situ passivation material is blind is overcome, and the method has wide application prospects in the fields of heavy metal polluted farmland remediation and safety production.

The application discloses a synthetic cadmium-resistant bacterial group, a carbon-based microbial agent containing the same, and a preparation method and application thereof, and belongs to the technical field of microbial soil remediation. The synthetic cadmium-resistant bacterial group is composed of Pseudomonas putida RC1, Citrobacter braakii RS1 and Acinetobacter johnsonii RZ1. The bacterial group is compounded with carbon-based materials to form a carbon-based microbial agent, which can significantly reduce the content of effective cadmium in soil, promote the transformation of cadmium from acid-soluble state to oxidizable state and residual state, inhibit the absorption of cadmium by plants, and improve crop yield. The agent shows stable remediation effect in cadmium-contaminated paddy soils of various parent materials, such as acid purple soil, neutral purple soil, calcareous purple soil, typical yellow soil and grey fluvo-aquic soil, has broad spectrum applicability, and is suitable for safe production and soil remediation of cadmium-contaminated farmland.

The invention relates to a seed coating for increasing calcium content in peanuts and application thereof, the coating comprises a calcium fertilizer, a film forming substance, a synergist and a dispersant, the raw materials comprise, by mass, 1-3 parts of the calcium fertilizer, 0.1-0.3 part of the synergist, 0.03-0.06 part of the dispersant, and 2-4 parts of the film forming substance. By coating the peanut seeds, the content of endogenous calcium in the peanuts is enhanced, and the requirement of the peanuts for calcium in the early growth stage is reduced, so that cadmium entering peanut bodies through root calcium ion channels is reduced, and the content of cadmium in harvested peanut seeds is reduced. Field trials prove that the cadmium content in the harvested peanuts can be reduced by about 39% when the coated seeds are sown in the acid cadmium-polluted soil; the method is easy and convenient to operate and low in cost, overcomes the defects of the traditional complex cadmium reduction technology of applying a passivating agent to the soil and the like in the field, is not prone to causing the soil environment risk, has the good peanut cadmium reduction rate and is suitable for large-area application and popularization.

The invention discloses a seed soaking agent for reducing cadmium content in wheat grains in cadmium-polluted soil and application thereof. The effective component of the seed soaking agent is a silver nitrate solution. The seed soaking agent is prepared by mixing silver nitrate according to a scientific ratio, the preparation process is simple and easy to implement, the required concentration is extremely low, and the raw material cost and the use amount are remarkably reduced. Wheat seeds are soaked by the seed soaking agent, and absorption and transfer of cadmium in soil by wheat can be effectively inhibited, so that the cadmium content in wheat grains is remarkably reduced, and the quality safety of agricultural products is guaranteed. Besides, the use method of the seed soaking agent is simple and quick, complex equipment or high investment is not needed, the agricultural production cost is greatly reduced, and the agricultural production efficiency is improved. Therefore, the method has wide application prospects and remarkable economic benefits in the aspects of reducing the cadmium content of the wheat grains, guaranteeing food safety, promoting agricultural sustainable development and the like.

The invention provides a regeneration method for hollow microspheres capable of adsorbing heavy metals, and belongs to the technical field of heavy metal contaminated soil remediation. The invention utilizes calcium disodium ethylenediaminetetraacetate in a backwashing solution to complex with cadmium in used hollow heavy metal adsorption microspheres, so that cadmium is leached from the microspheres. Meanwhile, Ca and Na in calcium disodium ethylenediaminetetraacetate are ion-exchanged with cadmium to reduce the cadmium content in the microspheres. Ca in calcium disodium ethylenediaminetetraacetate is ion-exchanged with other cations in the microsphere material to perform re-crosslinking to maintain the mechanical strength of the material. Calcium laurate in the backwashing solution complexes metal cations and is adsorbed on the surface of the microsphere material to reduce surface tension and weaken adhesion between cadmium ions and the microsphere material. Cadmium is backwashed from the microsphere material to obtain pretreated microspheres. The mechanical strength is improved through crosslinking to obtain regenerated hollow heavy metal adsorption microspheres.

The invention discloses a method for repairing acidic cadmium-polluted soil by using combined application of an alkaline calcium source, and belongs to the technical field of polluted soil repairing. The method comprises the following steps: calculating the amount of an alkaline calcium source required to be applied according to the pH value and the cadmium pollution level in the acidic cadmium polluted soil, spreading the alkaline calcium source and a fertilizer on the surface of the soil, and uniformly mixing to realize the remediation of the acidic cadmium polluted soil. The soil conditioner can improve the pH value of soil, increase the fertility of the soil, passivate soil cadmium, change the retention form of cadmium, reduce the absorption of plants to heavy metal cadmium, relieve heavy metal cadmium pollution from the two aspects of soil and plant absorption, achieve the purposes of reducing acid and cadmium and improving the product quality, especially reduce the cadmium content in rice grains, and improve the yield of rice. And the safety range specified by the national standard can be reduced.

This invention relates to a method for promoting the germination of buckwheat seeds under cadmium stress and alleviating cadmium toxicity during the seedling stage. The method includes treating buckwheat seeds with a melatonin reagent before germination. The method involves contacting the plant seeds with a melatonin solution at a concentration of 100-500 μmol / L. The method provided by this invention can effectively improve the germination potential and germination rate of buckwheat seeds under cadmium stress, enabling uniform and rapid germination. This invention solves the important problem of how to ensure normal germination of buckwheat in cadmium-contaminated soil in agricultural production and has significant application value in production. This is likely because pretreatment with a melatonin reagent can induce the expression of antioxidant enzyme activity, scavenge the large number of free radicals generated by cadmium stress, alleviate oxidative stress, reduce oxidative damage, and maintain a low level of membrane lipid peroxidation in the seeds, thereby promoting normal seed germination.

The invention discloses a strain of tolerant bacillus DH111 and its application in alleviating plant cadmium toxicity, belonging to the technical field of heavy metal contaminated soil remediation. The invention discloses a strain of tolerant bacillus DH111, and its deposit number is CGMCC No.26845. The tolerant bacillus DH111 disclosed by the invention has a significant promoting effect on corn seedlings' tolerance to cadmium toxicity, photosynthesis and antioxidant enzyme activity to varying degrees under the heavy metal cadmium stress environment; the tolerant bacillus DH111 can be applied to production, has the effect of promoting plant growth under cadmium stress, and is of great significance for repairing cadmium-contaminated soil and protecting the ecological environment.

The present invention discloses a rice OsNramp5 mutant M41, a genotype and an application thereof, and the technical field of rice mutagenesis breeding. Compared with the OsNramp5 gene sequence of Nipponbare rice, the nucleotide sequence of the OsNramp5 mutant M41 comprises the following base substitution: a base substitution G to A occurs at position 8877807 of chromosome 7. The present invention is of great significance in enriching the gene diversity related to low cadmium accumulation, balancing the positive and negative linkage effects of OsNramp5 on rice growth, development and yield, and exerting the socialization effect of low cadmium accumulation rice varieties.

The invention discloses application of scenedesmus in amorphophallus bulbifer planting, and belongs to the technical field of amorphophallus bulbifer planting. In the planting process of the amorphophallus bulbifer, scenedesmus liquid with the biomass of 3-4 g / L is applied once a week, the application amount is 1.4-1.5 ml / m < 2 >, growth of the amorphophallus bulbifer can be promoted, and absorption of cadmium by the amorphophallus bulbifer can be reduced. The method is efficient and easy to operate, and a new technical method is provided for promoting growth of the amorphophallus bulbifer and inhibiting absorption of cadmium by the amorphophallus bulbifer.

The invention discloses a treatment method for removing cadmium from contaminated biomass by using Aspergillus niger, and the treatment method comprises the following steps: using Aspergillus niger as an exogenous added fungus to extract cadmium from contaminated biomass alone, optimizing the optimal conditions by using the response surface method, and using the pretreatment method based on the optimal conditions of the response surface to work together with Aspergillus niger to complete the removal of cadmium from contaminated biomass. The treatment method of the invention performs shake flask extraction and culture of Aspergillus niger and contaminated biomass in a microbial extraction manner, which can achieve effective treatment of cadmium-contaminated biomass after plant restoration, has the advantages of good treatment effect, low investment, green environmental protection, low technical management requirements, simple operation, etc., and can also achieve the reuse of the treated biomass as fertilizer, which has good environmental benefits, social benefits and economic benefits.

This invention discloses a liquid microalgae fertilizer that can reduce the cadmium content of rice. The liquid microalgae fertilizer for reducing cadmium content in rice is composed of the following components by mass percentage: 50%-75% concentrated algae solution, 5%-12% humic acid, 2%-8% potassium fulvate, 0.1%-0.5% xanthan gum, 0.1%-0.5% sodium alginate, and the remainder being water.