阅读说明：本技术 一种能够降低水稻重金属镉污染的肥料及其应用 (Fertilizer capable of reducing heavy metal cadmium pollution of rice and application thereof ) 是由 彭玉林 张兆冬 *** 王永露 钱荣 于 2019-10-16 设计创作，主要内容包括：本发明涉及一种能够降低水稻重金属镉污染的肥料及其应用,其组分包括按重量份计：作物秸秆粉15-35份,益生菌15-35份,亚硫酸盐10-15份,酸碱平衡剂2～3份,生物吸附剂10-15份。本发明方案的肥料能够有效固化土壤中的重金属镉,抑制水稻对土壤中镉的吸收,从而降低种植水稻的镉含量。(The invention relates to a fertilizer capable of reducing heavy metal cadmium pollution of rice and application thereof, wherein the fertilizer comprises the following components in parts by weight: 15-35 parts of crop straw powder, 15-35 parts of probiotics, 10-15 parts of sulfite, 2-3 parts of acid-base balancing agent and 10-15 parts of biological adsorbent. The fertilizer provided by the invention can effectively solidify heavy metal cadmium in soil, and inhibit the absorption of rice to cadmium in soil, so that the cadmium content of the planted rice is reduced.)

1. A fertilizer capable of reducing heavy metal cadmium pollution of rice is characterized in that: the fertilizer comprises the following components in parts by weight:

15-35 parts of crop straw;

5-10 parts of probiotics;

10-15 parts of sulfite;

2-3 parts of an acid-base balancing agent;

10-15 parts of a biological adsorbent;

wherein the probiotic is a mixture of streptomyces microflavus, lactic acid bacteria, sulfate reducing bacteria and aspergillus niger.

2. The fertilizer capable of reducing rice pollution caused by heavy metal cadmium according to claim 1, wherein the fertilizer comprises the following components in percentage by weight: the probiotics comprise the following components in percentage by weight:

15-20% of streptomyces microflavus powder;

20-30% of lactobacillus powder;

sulfate reducing bacteria powder (20-30)%;

aspergillus niger powder (25-35)%;

in the probiotics, the sum of the mass percent of various beneficial powders is 100 percent, and the effective viable count is (1.5-2.0) multiplied by 10¹⁰cfu/g。

3. The fertilizer capable of reducing rice pollution caused by heavy metal cadmium according to claim 1, wherein the fertilizer comprises the following components in percentage by weight: the crop straw comprises at least one of wheat straw, rice straw or soybean straw.

4. The fertilizer capable of reducing rice pollution caused by heavy metal cadmium according to claim 1, wherein the fertilizer comprises the following components in percentage by weight: the fertilizer also comprises at least one of rice hulls, rapeseed meal, peanut meal or bean meal.

5. The fertilizer capable of reducing rice pollution caused by heavy metal cadmium according to claim 1, wherein the fertilizer comprises the following components in percentage by weight: the sulfite comprises at least one of sodium sulfite or ferrous sulfite.

6. The fertilizer capable of reducing rice pollution caused by heavy metal cadmium according to claim 1, wherein the fertilizer comprises the following components in percentage by weight: the acid-base balancing agent is at least one of calcium superphosphate, ammonium phosphate, monopotassium phosphate and plant ash.

7. The fertilizer capable of reducing rice pollution caused by heavy metal cadmium according to claim 1, wherein the fertilizer comprises the following components in percentage by weight: the biological adsorbent comprises a mixture of shrimp and crab shells and diatom.

8. The fertilizer capable of reducing rice pollution caused by heavy metal cadmium according to claim 7, wherein the fertilizer comprises the following components in percentage by weight: the mass ratio of the shrimp, crab shells to the diatom is (2-3) to 1.

9. The use of a fertilizer according to any one of claims 1 to 8 for reducing heavy metal cadmium contamination in rice, wherein: the fertilizer is applied to cadmium-polluted soil, and the application amount is 350-800kg/hm²。

10. Use according to claim 9, characterized in that: the fertilizer is applied once at least 5-8 days before plowing, before heading or after heading of the paddy field.

Technical Field

The invention relates to the technical field of fertilizers, in particular to a fertilizer capable of reducing heavy metal cadmium pollution of rice and application thereof.

Background

The heavy metal pollution of the soil has the characteristics of concealment, long-term property, irreversible property and the like, not only influences the rice yield in the rice production, but also is easy to enrich in rice, seriously influences the sanitary quality and the nutritional quality of the rice, and has potential hazard to the health of the masses. Therefore, the prevention and control of the heavy metals in the rice crops have great significance for the sustainable utilization of farmlands, the reasonable distribution of the crops and the rice safety. Cadmium (Cadmium, Cd) is a heavy metal element with strong biological toxicity, and has a low background value in nature, but with the development of industry, Cadmium continuously enters a farmland ecosystem, so that the Cadmium is accumulated in farmland soil. According to statistics of Ministry of agriculture, more than 10% of cultivated land in China is polluted by cadmium (more than 0.3mg/Kg), cadmium pollution enters human bodies through food chains, and the cadmium pollution seriously harms human health after being eaten for a long time and even causes bone pain. Hunan is a 'country of nonferrous metals', and the cadmium pollution of paddy fields is seriously higher than that of the whole country.

The bioavailability of cadmium in soil is the most direct relevant factor for rice to absorb cadmium, and is easily influenced by physicochemical properties of soil pH value, oxidation-reduction potential (Eh), organic matters and the like. The improvement of the physical and chemical properties of the soil can regulate the bioavailability of cadmium in the soil and influence the absorption and accumulation of the rice on the cadmium. Fertilization is a main cultivation measure in the growth process of rice, and can effectively influence the content and the existing form of heavy metals in soil.

At present, methods for repairing heavy metal contaminated soil include microbial repair, phytoremediation, physicochemical repair and the like, and the physicochemical repair includes chemical solidification, soil leaching, electrokinetic repair and the like. The physical and chemical remediation has the advantages of high remediation speed, good effect, proper price, simple operation and the like, but has large dosage and is easy to cause secondary pollution; the plant restoration is ecological and environment-friendly, but the period is long, the consumption is large, and the operation is complicated; the microbial remediation has the advantages of simple operation and ecological environmental protection, but the existing microbial remediation method cannot meet the requirement of large-scale application in farmlands and has poor effect.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a fertilizer capable of reducing the heavy metal cadmium pollution of rice.

According to the first aspect of the invention, the fertilizer capable of reducing heavy metal cadmium pollution of rice comprises the following components in parts by weight:

15-35 parts of crop straw;

5-10 parts of probiotics;

10-15 parts of sulfite;

2-3 parts of an acid-base balancing agent;

10-15 parts of a biological adsorbent;

wherein the probiotic is a mixture of streptomyces microflavus, lactic acid bacteria, sulfate reducing bacteria and aspergillus niger.

The fertilizer provided by the embodiment of the invention has at least the following beneficial effects: the fertilizer provided by the invention can effectively solidify heavy metal cadmium in soil and inhibit the absorption of rice to cadmium in soil, so that the cadmium content of the planted rice is reduced; aspergillus niger can produce amylase, acid protease, cellulase, pectinase, glucose oxidase, citric acid, gluconic acid and gallic acid, degrade organic pollutants in soil, destroy the structure of the heavy metal ion complex and prevent the organic pollutants from being absorbed and utilized by rice; lactic acid bacteria metabolize to generate organic acids such as lactic acid and the like, so that the pH value and the oxidation-reduction potential of the environment are obviously reduced, meanwhile, sulfite can be compounded with the organic acids generated by the metabolism of the lactic acid bacteria, the black yellow mold and the like to reduce the oxidation-reduction potential in the soil, sulfate reducing bacteria convert the sulfite into sulfur ions, so that the active cadmium in the soil is promoted to be converted into insoluble cadmium sulfide, and the bioavailability of the cadmium is finally reduced; streptomyces microflavus in the probiotics is metabolized to generate growth regulating components necessary for growth of crops such as auxin, antibiotics, succinic acid, cytokinin and the like, nitrogen, phosphorus and potassium in soil can be used for improving soil fertility, the using amount of a fertilizer is reduced, in addition, the Streptomyces microflavus can synergistically promote formation of humic acid, the restoring capability of the soil to heavy metal pollution is improved, and the air permeability of the soil is improved.

According to some embodiments of the invention, the probiotic comprises, in weight parts percent:

15-20% of streptomyces microflavus powder;

20-30% of lactobacillus powder;

sulfate reducing bacteria powder (20-30)%;

aspergillus niger powder (25-35)%;

in the probiotics, the mass of various beneficial powders is hundredThe sum of the fractions is 100%, and the effective viable count is (1.5-2.0) x 10¹⁰cfu/g。

According to some embodiments of the invention, the crop straw comprises at least one of wheat straw, rice straw or soybean straw.

According to some embodiments of the invention, the fertilizer further comprises at least one of rice hulls, rapeseed meal, peanut meal, or soybean meal.

According to some embodiments of the invention, the sulfite comprises at least one of sodium sulfite or ferrous sulfite.

According to some embodiments of the invention, the acid-base balancing agent is at least one of calcium superphosphate, ammonium phosphate, monopotassium phosphate and plant ash.

According to some embodiments of the invention, the biological adsorbent comprises a mixture of shrimp and crab shells and diatoms.

According to some embodiments of the invention, the mass ratio of the shrimp, crab shells and diatom is (2-3): 1.

According to the application of the second aspect of the embodiment of the invention, the fertilizer is applied to cadmium-polluted soil at the application rate of 350-800kg/hm²。

According to some embodiments of the invention, the fertilizer is applied at least once before plowing, before heading or 5-8 days after heading of the paddy field; preferably, the fertilizer is applied once respectively before plowing, before heading or 5-8 days after heading.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Detailed Description

In order to explain the technical content, the objects and the effects of the present invention in detail, the following description will be given with reference to the embodiments.

The fertilizer capable of reducing the heavy metal cadmium pollution of rice comprises the following components in parts by weight:

15-35 parts of crop straw;

5-10 parts of probiotics;

10-15 parts of sulfite;

2-3 parts of an acid-base balancing agent;

10-15 parts of a biological adsorbent;

wherein the probiotic is a mixture of streptomyces microflavus, lactic acid bacteria, sulfate reducing bacteria and aspergillus niger.

And an acid-base balancing agent is added to adjust the pH value of the fertilizer, so that the problem that the acidity of the soil is too strong due to excessive organic acid generated by metabolism of lactic acid bacteria is avoided. The crop straws can provide carbohydrates and other nutrient substances for microorganisms, meanwhile, the crop straws can promote cadmium in the polluted soil to be dissolved out, the dissolved cadmium is converted into cadmium sulfide in an insoluble state through the action of components such as probiotics, so that the absorption and utilization of the rice on the cadmium in the soil are reduced, and meanwhile, the straws contain a large amount of cellulose and can have an adsorption effect on metal cadmium. The biological adsorbent is added into the fertilizer, the biological adsorbent is used for adsorbing and fixing cadmium ions in soil, so that the cadmium ions are prevented from migrating, and meanwhile, the biological adsorbent naturally exists, so that the hidden danger that the chemical adsorbent possibly generates secondary pollution is avoided.

According to some embodiments of the invention, the probiotic comprises, in weight parts percent:

15-20% of streptomyces microflavus powder;

20-30% of lactobacillus powder;

sulfate reducing bacteria powder (20-30)%;

aspergillus niger powder (25-35)%;

in the probiotics, the sum of the mass percent of various beneficial powders is 100 percent, and the effective viable count is (1.5-2.0) multiplied by 10¹⁰cfu/g。

According to some embodiments of the invention, the crop straw comprises at least one of wheat straw, rice straw or soybean straw.

According to some embodiments of the invention, the fertilizer further comprises at least one of rice hulls, rapeseed meal, peanut meal, or soybean meal. The rice hulls contain rich silicon, and after being decomposed and utilized by probiotics, the silicon in the rice hulls is released and can be absorbed and utilized by rice, so that cadmium adsorption channels are occupied, and the adsorption of the rice to cadmium is reduced; in addition, the rice hulls, the rapeseed meal, the peanut meal or the soybean meal contain a large amount of carbohydrates, trace elements and amino acids, which can provide nutrient substances for the metabolism of microorganisms, and meanwhile, the trace elements, the amino acids and the like can finally provide nutrient substances for rice; meanwhile, components such as nicotinic acid, choline and anti-nutritional factors contained in rapeseed meal and soybean meal can generate certain auxiliary effect on rice pest resistance, so that the application amount of the pesticide is reduced, and the fertilizer has good continuity on reduction of cadmium pollution of soil; the peanut meal also has the function of promoting the growth, development and metabolism of microorganisms, and can promote the proliferation of lactic acid bacteria, mould and other fungi.

According to some embodiments of the invention, the sulfite comprises at least one of sodium sulfite or ferrous sulfite.

Sodium sulfite is used as a sulfurous acid source, so that the production can be reduced; the ferrous sulfite provides a sulfurous acid source, and simultaneously can supplement iron element for the rice, ferrous ions can be preferentially combined with transport protein of iron, so that the probability of cadmium being combined with the cadmium is reduced, partial absorption with cadmium ions is formed, the absorption of the rice to cadmium is reduced, in addition, partial ferrous ions are reduced into iron salts, the iron salts are hydrolyzed in the rice field to form colloid, the adsorption effect of soil to cadmium is assisted to be enhanced, and the migration capacity of cadmium is further reduced.

According to some embodiments of the invention, the acid-base balancing agent is at least one of calcium superphosphate, ammonium phosphate, monopotassium phosphate and plant ash. When the pH value of the fertilizer is adjusted, the alkaline balancing agent ensures the balance of N, P and K in the fertilizer, which is beneficial to enhancing the fertilizer efficiency and reducing heavy metal pollution.

According to some embodiments of the invention, the biological adsorbent comprises a mixture of shrimp and crab shells and diatoms. The shrimp, crab shells and diatom have good adsorption effect on heavy metals, and diatom contains a large amount of silicon elements, so that the silicon elements can be better absorbed and utilized by rice under the decomposition effect of probiotics, the absorption rate of cadmium can be reduced, and rice blast and the like caused by silicon deficiency of the rice can be prevented and treated. Besides calcium element, the shrimp and crab shells also contain a large amount of zinc element, so that rice shrinkage and other symptoms caused by zinc deficiency of rice can be avoided, and the cold resistance and the freezing resistance of rice seedlings can be improved.

According to some embodiments of the invention, the mass ratio of the shrimp, crab shells and diatom is (2-3): 1.

According to the application of the second aspect of the embodiment of the invention, the fertilizer is applied to cadmium-polluted soil at the application rate of 350-800kg/hm²。

According to some embodiments of the invention, the fertilizer is applied at least once before plowing, before heading or 5-8 days after heading of the paddy field; preferably, the fertilizer is applied once respectively before plowing, before heading or 5-8 days after heading.

The first embodiment of the invention is as follows: a fertilizer capable of reducing heavy metal cadmium pollution of rice is prepared by the following steps:

uniformly mixing 20 parts of soybean straw powder, 5 parts of probiotics, 10 parts of sodium sulfite, 2 parts of acid-base balancing agent and 15 parts of biological adsorbent. Wherein the probiotics is a mixture obtained by uniformly mixing 15% of streptomyces microflavus powder, 25% of lactobacillus powder, 30% of sulfate reducing bacteria powder and 30% of aspergillus niger powder, and the effective viable count in the mixture is about 1.5 multiplied by 10¹⁰cfu/g. The acid-base balancing agent is a mixture of calcium phosphate and plant ash in a mass ratio of 1: 1. The biological adsorbent is a mixture of shrimp, crab shells and diatom. If the fertilizer is applied as the fertilizer before ploughing and heading of the paddy field, the mass ratio of the shrimp, crab shells to the diatom is 3:1, otherwise, the mass ratio is 2: 1.

The second embodiment of the invention is as follows: a fertilizer capable of reducing heavy metal cadmium pollution of rice is prepared by the following steps:

uniformly mixing 15 parts of wheat straw powder, 10 parts of probiotics, 15 parts of ferric sulfite, 3 parts of acid-base balancing agent and 15 parts of biological adsorbent. Wherein the probiotics is a mixture obtained by uniformly mixing 20% of streptomyces microflavus powder, 20% of lactobacillus powder, 30% of sulfate reducing bacteria powder and 30% of aspergillus niger powder, and the effective viable count in the mixture is about 1.8 multiplied by 10¹⁰cfu/g. The acid-base balancing agent is a mixture of calcium phosphate, ammonium phosphate and monopotassium phosphate with the mass ratio of 1:1: 1. The biological adsorbent is a mixture of shrimp, crab shells and diatom. Before and after ploughing in rice fieldWhen the fertilizer before the ear is applied, the mass ratio of the shrimp, crab shells and diatom is 3:1, otherwise, the mass ratio is 2: 1.

The third embodiment of the invention is as follows: a fertilizer capable of reducing heavy metal cadmium pollution of rice is prepared by the following steps:

uniformly mixing 35 parts of rice straw powder, 8 parts of probiotics, 12 parts of ferrous sulfate, 3 parts of acid-base balancing agent and 10 parts of biological adsorbent. Wherein the probiotics is a mixture obtained by uniformly mixing 18 percent of streptomyces microflavus powder, 28 percent of lactobacillus powder, 26 percent of sulfate reducing bacteria powder and 28 percent of aspergillus niger powder, and the effective viable count in the mixture is about 2.0 multiplied by 10¹⁰cfu/g. The acid-base balancing agent is prepared from the following components in a mass ratio of 1:1: 1: 2 a mixture of calcium phosphate, ammonium phosphate, monopotassium phosphate and plant ash. The biological adsorbent is a mixture of shrimp, crab shells and diatom. If the fertilizer is applied as the fertilizer before ploughing and heading of the paddy field, the mass ratio of the shrimp, crab shells to the diatom is 3:1, otherwise, the mass ratio is 2: 1.

The fourth embodiment of the invention is as follows: a fertilizer capable of reducing heavy metal cadmium pollution of rice is different from the fertilizer in the first embodiment in that: and 5 parts of rice husk are also added.

The fifth embodiment of the invention is as follows: a fertilizer capable of reducing heavy metal cadmium pollution of rice is different from the fertilizer in the first embodiment in that: and 5 parts of peanut meal is also added.

The sixth embodiment of the invention is as follows: a fertilizer capable of reducing heavy metal cadmium pollution of rice is different from the fertilizer in the first embodiment in that: 5 parts of soybean meal is also added.

The first comparative example of the present invention is: a fertilizer which differs from the first embodiment by: the aspergillus niger is not contained, and the weight parts of other substances are unchanged.

The second comparative example of the present invention is: a fertilizer which differs from the first embodiment by: the sulfate reducing bacteria is not contained, and the weight parts of other substances are unchanged.

The third comparative example of the present invention is: a fertilizer which differs from the first embodiment by: the product does not contain acid-base balancing agent, and the weight parts of other substances are unchanged.

The fourth comparative example of the present invention is: a fertilizer which differs from the first embodiment by: does not contain probiotics, and the weight parts of other substances are not changed.

The fertilizers in the above examples and comparative examples were used for rice planting tests, and rice planting was performed by a potting method, and the specific planting method and test process were as follows:

firstly, preparing test soil:

the soil to be tested is red loam, is collected from a rice field near a mountain of a great-distance highway of Changsha in Hunan, surface soil with the thickness of 0-30 cm is selected, naturally dried, impurities in the soil are removed, and the soil is ground and sieved by a 30-mesh sieve for later use.

Simulating heavy metal pollution of soil: weighing a certain amount of solid cadmium chloride, adding the solid cadmium chloride into soil to be tested, fully mixing the solid cadmium chloride and the soil to be tested uniformly, adding deionized water to enable the water content of the soil to reach about 60% of the maximum water holding capacity, supplementing water in time every day, keeping the water content of the soil, culturing the soil for 8 weeks at room temperature, and simulating the heavy metal cadmium-polluted soil. After 8 weeks of measurement (the measurement method is referred to soil environmental quality Standard (GB15618-2008)), the cadmium content in the soil is 0.657 mg/kg.

II, a test process:

1. planting rice: the test is totally set with 11 groups, each group is provided with 3 repeated tests, 1-6 groups are respectively applied with fertilizers of corresponding examples, 7-10 groups are applied with fertilizers of corresponding examples, and 11 groups are blank controls (applied with equal amount of common commercial nitrogen-phosphorus-potassium compound fertilizers). Other operations (watering, pest management, etc.) and management of each group are consistent. And (3) respectively filling 10kg of the simulated soil prepared by the operation into each pot, wherein 6g of fertilizer is applied to 1-10 groups 10 days before sowing, the mixture is uniformly mixed, watering and irrigating are carried out, after water naturally falls to dryness, the rice is sowed, 30 rice seeds are sowed into each pot, and the rice variety is Xiangzaixuan No. 33. After the seeds emerged, 8 plants are fixed seedlings in each pot.

2. Fertilizing in a growth period: it is applied once more (5.5 g per pot) before heading and once more (5 g per pot) on the 8 th day after heading.

Thirdly, verifying the result:

after the rice is harvested, determining the thousand-grain weight of the rice, randomly extracting 20 brown rice, determining the cadmium content in the brown rice according to GB/T5009.15-2003, taking the average value of each group of tests as the final test result, wherein the detection indexes and results are shown in the following table 1:

TABLE 1

Group of	1	2	3	4	5	6	7	8	9	10	11
												Thousand Kernel weight (g)	21.6	21.9	21.8	22.2	22	22.1	20.5	20.8	20.2	19.9	19.7
Cadmium content (mg/kg)	0.248	0.237	0.231	0.213	0.235	0.243	0.299	0.297	0.250	0.334	0.391

In addition, the heading time and the rice time were earlier for the rice of example five, while the rice of example four was full and substantially free of empty rice. When the soil applied with the fertilizer is planted with late rice under the same conditions, the cadmium content of the late rice planted with the soil applied with the fertilizer of the sixth embodiment is obviously lower than that of the late rice planted with the soil applied with the fertilizer of the sixth embodiment.

Comparing the example group with the blank control group, the fertilizer applying the scheme of the invention can not only greatly reduce the cadmium content in the rice, but also improve the yield, and the example group 4 adding the rice hull can improve the yield by more than 12 percent and reduce the cadmium by 45 percent; comparing the control group with the blank control group, the yield of the probiotics which do not comprise the scheme (or only comprise part of the probiotics) is reduced, and meanwhile, the cadmium content is still higher; the control group containing no acid-base equilibrium agent showed a significant decrease in cadmium content, but the yield was much lower than the example group.

The parts in the above examples are parts by weight.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent modifications made by the present invention in the specification or directly or indirectly applied to the related technical field are included in the scope of the present invention.