Organic fertilizer and fermentation method and application thereof

Abstract

The present application discloses an organic fertilizer and its fermentation method and application, belonging to the technical field of organic fertilizer preparation. The method includes S1. Preparation of fermentation auxiliary materials: 1. Using straw as a substrate, crushing into particles; processing under high temperature and high pressure to obtain puffed straw particles; 2. Drying the puffed straw particles to 20-30% under 70-80°C; 3. Adding composite bacteria, starch, and adhesive, mixing evenly to obtain composite biological fermentation auxiliary materials; the composite bacteria is obtained by compounding the following weight parts: 50-60 parts of actinomycetes, 50-60 parts of bacillus, 50-60 parts of nitrogen-fixing bacteria, 0-1 part of Trichoderma, 0-1 part of yeast, and 0-1 part of lactic acid bacteria; the weight ratio of puffed straw crushed: starch: bacteria: adhesive = (8.5-9.2): (0.2-0.8): (0.1-0.3): (0.1-0.3); S2. Mixing and fermenting organic solid waste raw materials with composite biological fermentation auxiliary materials and fermentation product recycled materials. The method has good fermentation effect, significant temperature rise, and long duration of high temperature, and the obtained organic fertilizer is of high quality.

Description

Technical Field

[0001] The present application belongs to the technical field of organic fertilizer preparation, and specifically relates to an organic fertilizer and a fermentation method and application thereof. Background Art

[0002] Excessive nitrogen, phosphorus and other elements lead to soil acidification, a decrease in soil organic matter, phosphorus non-point source pollution, a decrease in groundwater and surface water quality and eutrophication, and a greenhouse effect. Therefore, organic fertilizers should be actively promoted to reduce the adverse effects of chemical fertilizers on the environment.

[0003] Organic fertilizers come from a wide range of sources, including the remains or metabolites (feces) of various animals and plants. After aerobic fermentation and other processes, they are used as organic fertilizers. Organic fertilizers are rich in natural organic matter, which can increase and renew the organic matter content of the soil, improve the physical, chemical and biological properties of the soil, and fundamentally coordinate the soil's fertilizer supply performance; they can improve the growth characteristics of crops and the quality of agricultural products; they can increase bioactive substances, promote the reproduction of microorganisms, and improve the ability of plants to resist diseases and insects. In addition, the production of organic fertilizers in coordination with animal manure and agricultural waste straw can not only solve the problem of organic solid waste pollution in animal husbandry, but also solve the problems of large production of agricultural straw waste and excessive PM2.5 caused by on-site incineration.

[0004] Although organic fertilizer production has many advantages, the aerobic fermentation process of organic fertilizer production on the market is extensive and has many problems. The main manifestations are: 1) the ingredients in the fermentation process are simple, there is no advantageous compound biological fermentation auxiliary material added, and the fermentation effect is poor; 2) the harmless temperature is not enough, the pathogens are not inactivated, and there are biosafety risks; 3) the quality of the fermentation product is poor, and after application, it not only cannot promote plant growth, but also has the hazards of burning seedlings and polluting the environment. Therefore, solving the bottleneck problem of organic fertilizer fermentation is the key to promoting organic fertilizer to move strongly into the fertilizer market and have a place.

[0005] CN 113773986 B discloses a bacterial agent for rapid heating of organic solid waste aerobic fermentation in winter, but the heating temperature of organic fertilizer fermentation, high temperature duration and sterilization effect still need to be improved. Summary of the invention

[0006] In order to solve the above problems, an organic fertilizer and a fermentation method and application thereof are provided. The organic fertilizer product obtained by the method has high quality and can significantly promote plant growth after application.

[0007] The specific technical solutions of this application are as follows:

[0008] A fermentation method for organic fertilizer comprises the following steps:

[0009] S1. Preparation of fermentation excipients:

[0010] Step 1: Using straw as a base, crushing it into particles; treating it under high temperature and high pressure to obtain expanded straw particles;

[0011] Step 2: Dry the puffed straw pellets to 20-30% at 70-80°C;

[0012] Step 3: Add composite bacteria, starch and adhesive to the dried puffed straw particles, and mix them evenly to obtain composite biological fermentation auxiliary materials;

[0013] The composite bacteria is obtained by compounding the following components in parts by weight: 50-60 parts of actinomycetes, 50-60 parts of bacillus, 50-60 parts of nitrogen-fixing bacteria, 0-1 part of Trichoderma, 0-1 part of yeast, and 0-1 part of lactic acid bacteria;

[0014] The weight ratio of puffed straw shreds: starch: bacteria: adhesive = (8.5-9.2): (0.2-0.8): (0.1-0.3): (0.1-0.3);

[0015] S2. Mix the organic solid waste raw materials with the composite biological fermentation auxiliary materials and the fermentation product recycled materials in a mass ratio of 1: (0.1~0.2): (0.1~0.55), and continue fermenting at 50~70°C for 5~7 days.

[0016] Optionally, in step S2, the recycled fermentation product is a composite biological fermentation auxiliary material containing undecomposed and cultured dominant bacteria.

[0017] Optionally, the fermentation product recycled material is prepared by the following method: mixing the organic solid waste raw material and the composite biological fermentation auxiliary material in a mass ratio of 1:0.1-0.5, and continuing to ferment at 55-65°C for 8-10 days.

[0018] Optionally, in step S2, the organic solid waste raw material is livestock and poultry manure, including pig manure, chicken manure, cow manure, sheep manure and duck manure.

[0019] Optionally, in step 1, the particles are crushed into 1-5 cm particles.

[0020] Optionally, in step 2, the temperature condition is 120-180° C. and the pressure condition is 0.5-1.5 MPa.

[0021] Optionally, the adhesive in step 4 includes bentonite, urea-formaldehyde resin, or epoxy resin.

[0022] Optionally, in step five, the cutting is performed until the diameter of the mixed material is ≤1 cm to obtain a particle mixture.

[0023] The present application also provides an organic fertilizer prepared by the above preparation method.

[0024] The present application also provides the use of the above organic fertilizer in soil fertility enhancement.

[0025] The straw used in this application is puffed straw. Ordinary straw is rich in cellulose, hemicellulose and lignin. Although these substances are organic matter, they are directly used for aerobic fermentation and are not easily decomposed and utilized by microorganisms. By using puffing technology, that is, after high temperature and high pressure treatment, these substances will soften and liquefy, decompose into organic components that are easily degraded by microorganisms, and at the same time, during the puffing process, the water and starch inside the straw will undergo a violent vaporization reaction, generating a large amount of water vapor and heat, causing the straw to expand and burst rapidly, increase in volume, and form a loose porous structure inside. The specific surface area of ​​the structure is increased, which is more conducive to the attachment and mass reproduction of microorganisms.

[0026] The beneficial effects of this application include but are not limited to:

[0027] 1. This application uses specific composite bacteria: actinomycetes, bacillus, nitrogen-fixing bacteria, trichoderma, yeast and lactic acid bacteria, which can play a synergistic role and efficiently decompose easily decomposable organic components in starch and solid waste; change the air permeability and heat preservation capacity of the raw materials to the greatest extent, promote the rapid diffusion and effective utilization of oxygen, accelerate the temperature rise and high temperature maintenance after temperature rise, and achieve efficient sterilization and water vapor evaporation.

[0028] 2. The present application adds recycled fermentation auxiliary materials prepared under specific conditions, and the recycled fermentation auxiliary materials include cultured superior strains and more easily utilized residual fermentation auxiliary materials; the recycled materials are fermented with composite biological fermentation auxiliary materials, livestock and poultry manure and other organic solid waste raw materials, which can not only realize the efficient utilization of composite biological fermentation auxiliary materials and reduce production costs to a certain extent, but also greatly promote the fermentation process. The recycled fermentation auxiliary materials of the present application are obtained by controlling the fermentation degree. By controlling the fermentation degree, recycled fermentation auxiliary materials with specific advantages are obtained, which are applied in the preparation of organic fertilizers, overcoming the technical barriers of quality production of organic fertilizers prepared by fermentation in the prior art. DETAILED DESCRIPTION

[0029] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0030] Unless otherwise specified, the raw materials and catalysts in the examples of this application were purchased through commercial channels.

[0031] Example 1

[0032] A fermentation method for organic fertilizer is prepared by the following method:

[0033] S1. Preparation of fermentation excipients:

[0034] Step 1: Using corn stalks as a substrate, crushing them into 1-5 cm particles; treating them at 150°C and 1 MPa to obtain expanded stalk particles;

[0035] Step 2: Dry the puffed straw pellets at 75°C to a moisture content of about 25%;

[0036] Step 3: Add bacteria, starch and adhesive (bentonite) to the dried puffed straw particles and mix them evenly to obtain composite biological fermentation auxiliary materials;

[0037] The strain is obtained by compounding 55 parts of actinomycetes, 55 parts of bacillus, 2 parts of nitrogen-fixing bacteria, 1 part of Trichoderma, 1 part of yeast and 1 part of lactic acid bacteria by weight;

[0038] The weight ratio of puffed straw shreds: starch: bacteria: binder (bentonite) = 9: 0.5: 0.2: 0.2;

[0039] S2. Mix the organic solid waste raw materials (livestock and poultry manure) with the composite biological fermentation auxiliary materials and the fermentation product recycled materials in a mass ratio of 1:0.2:0.55, and continue to ferment for 7 days at a gradually rising temperature of 50-70℃. After the high temperature period of the fermentation process (no longer heating up, at the temperature peak period), turn the fermentation regularly every 2 days or so. The turning process breaks up the large pieces of materials and mixes the upper and lower layers of materials, ensuring uniform air supply without dead ends while also ensuring the overall quality of the fermentation products.

[0040] The specific preparation method of the fermentation product recycled material is as follows:

[0041] The organic solid waste raw materials and the composite biological fermentation auxiliary materials are mixed in a mass ratio of 1:0.5, and fermented at 50-70°C for 9 days. The obtained product is the first batch of fermentation product recycled materials, which contain composite biological fermentation auxiliary materials that have not been fully utilized and have been cultivated with dominant strains.

[0042] Example 2

[0043] A fermentation method for organic fertilizer is prepared by the following method:

[0044] S1. Preparation of fermentation excipients:

[0045] Step 1: Using potato straw as a substrate, crushing it into 1-5 cm particles; treating it at 120°C and 1.5 MPa to obtain puffed straw particles;

[0046] Step 2: Dry the puffed straw pellets at 80°C to a moisture content of 30%;

[0047] Step 3: Add bacteria, starch and adhesive (epoxy resin) to the dried puffed straw particles and mix them evenly;

[0048] The strain is obtained by compounding 50 parts of actinomycetes, 60 parts of bacillus, 2 parts of nitrogen-fixing bacteria, 1 part of Trichoderma, 1 part of yeast and 1 part of lactic acid bacteria by weight;

[0049] The weight ratio of puffed straw shreds: starch: bacteria: adhesive (epoxy resin) is 9.2: 0.8: 0.1: 0.1; the composite biological fermentation auxiliary material is obtained;

[0050] S2. Mix the organic solid waste raw materials (livestock and poultry manure) with the composite biological fermentation auxiliary materials and the recycled materials of the fermentation products in a mass ratio of 1:0.15:0.4, and continue to ferment for 6 days at a gradually increasing temperature of 50-68℃; turn the materials over regularly every 2 days or so after the high temperature period of the fermentation process. The turning process will break up the large pieces of materials and mix the upper and lower layers of materials, ensuring uniform air supply without dead corners while also ensuring the overall quality of the fermentation products.

[0051] The specific preparation method of the fermentation product recycled material is as follows:

[0052] The organic solid waste raw materials and the composite biological fermentation auxiliary materials are mixed in a mass ratio of 1:0.3, and fermented at 50-70°C for 10 days. The obtained product is the first batch of fermentation product recycled materials, which contain composite biological fermentation auxiliary materials that have not been fully utilized and have been cultivated with dominant strains.

[0053] Example 3

[0054] A fermentation method for organic fertilizer is prepared by the following method:

[0055] S1. Preparation of fermentation excipients:

[0056] Step 1: Using corn stalks as a substrate, crushing them into 1-5 cm particles; treating them at 180°C and 0.5 MPa to obtain expanded stalk particles;

[0057] Step 2: Dry the puffed straw pellets at 70°C to a moisture content of 20%;

[0058] Step 3: Add bacteria, starch and adhesive (bentonite) to the dried puffed straw particles and mix them evenly to obtain composite biological fermentation auxiliary materials.

[0059] The strain is obtained by compounding 60 parts of actinomycetes, 50 parts of bacillus, 2 parts of nitrogen-fixing bacteria, 1 part of Trichoderma, 1 part of yeast and 1 part of lactic acid bacteria by weight;

[0060] The weight ratio of puffed straw shreds: starch: bacteria: binder (bentonite) = 8.5: 0.2: 0.3: 0.3;

[0061] S2. Mix the organic solid waste raw materials (livestock and poultry manure) with the composite biological fermentation auxiliary materials and the recycled materials of the fermentation products in a mass ratio of 1:0.1:0.1, and continue to ferment for 5 days at a gradually increasing temperature of 50-69°C; turn the materials over regularly every 2 days or so after the high temperature period of the fermentation process. The turning process will break up the large pieces of materials and mix the upper and lower layers of materials, ensuring uniform air supply without dead corners while also ensuring the overall quality of the fermentation products.

[0062] The specific preparation method of the fermentation product recycled material is as follows:

[0063] The organic solid waste raw materials and the composite biological fermentation auxiliary materials are mixed in a mass ratio of 1:0.2, and fermented at 50-70°C for 9 days. The obtained product is the first batch of fermentation product recycled materials, which contain composite biological fermentation auxiliary materials that have not been completely decomposed and have been cultivated with dominant strains.

[0064] Example 4

[0065] The difference from Example 1 is that the strain is obtained by compounding 50 parts of actinomycetes, 60 parts of bacillus and 2 parts of nitrogen-fixing bacteria, and the rest is the same as Example 1.

[0066] Example 5 Different ratios of bacterial species

[0067] The difference from Example 1 is that the strain is obtained by compounding 30 parts of actinomycetes, 75 parts of bacillus, 3 parts of nitrogen-fixing bacteria, 1 part of Trichoderma, 1 part of yeast and 1 part of lactic acid bacteria;

[0068] Comparative Example 1

[0069] The difference from Example 1 is that the straw in the fermentation auxiliary material is ordinary straw (not expanded).

[0070] Comparative Example 2

[0071] The difference from Example 1 is that the degree of drying of the puffed straw particles is different, which is 15%.

[0072] Comparative Example 3

[0073] The difference from Example 1 is that different composite bacteria are used in the fermentation auxiliary materials; specifically, actinomycetes, Bacillus, nitrogen-fixing bacteria, Trichoderma, yeast, lactic acid bacteria, and acetic acid bacteria.

[0074] Comparative Example 4

[0075] The difference from Example 1 is that different composite bacteria are used in the fermentation auxiliary materials; specifically, Bacillus, nitrogen-fixing bacteria, Trichoderma, yeast, lactic acid bacteria, and Brevibacterium flavum.

[0076] Comparative Example 5

[0077] The difference from Example 1 is that the ratio of components in the fermentation auxiliary materials is different, namely, puffed straw particles: bacteria: starch: adhesive = 9:1.2:1:0.5.

[0078] Comparative Example 6

[0079] The difference from Example 1 is that the ratio of components in the fermentation auxiliary materials is different, namely, puffed straw particles: bacteria: starch: adhesive = 8:1.2:0.7:0.5.

[0080] Comparative Example 7

[0081] The difference from Example 1 is that no recycled fermentation product is added. The rest is the same as Example 1.

[0082] Comparative Example 8

[0083] The difference from Example 1 is that the preparation conditions of the fermentation product recycled material are different. The specific preparation method of the fermentation product recycled material is as follows:

[0084] The organic solid waste raw material and the composite biological fermentation auxiliary material are mixed in a mass ratio of 1:0.1-0.5, and fermented at 50-70° C. for 11 days to obtain the fermentation product recycled material. The rest is the same as in Example 1.

[0085] Comparative Example 9

[0086] The difference from Example 1 is that the preparation conditions of the fermentation product recycled material are different. The specific preparation method of the fermentation product recycled material is as follows:

[0087] The organic solid waste raw material and the composite biological fermentation auxiliary material were mixed in a mass ratio of 1:0.5, and fermented at 50-60° C. for 9 days to obtain the fermentation product recycling material. The rest was the same as in Example 1.

[0088] The fermentation effects of the examples and comparative examples when preparing organic fertilizers were tested, and the results are shown in Table 1.

[0089] Table 1 Fermentation effect

[0090]

[0091] According to the data in the above table, the fermentation effect in Examples 1-4 is better, and compared with Example 5 and Comparative Examples 1-9, the temperature rise is significant, the temperature rise rate is fast, the temperature rise duration is long, the high temperature duration is long, and the dehydration effect is also better. It can be achieved: the temperature rises to 45°C within 12h; the temperature rises to 50°C, and the highest temperature of 70°C can be sustained for 7 days.

[0092] The reason is that, compared with the ordinary straw in Comparative Example 1, the puffed straw in Example 1 is softened and liquefied after high temperature and high pressure treatment, and decomposed into organic components that are easily degraded by microorganisms. On the other hand, the moisture and starch inside the straw undergo a violent vaporization reaction, generating a large amount of water vapor and heat, causing the straw to expand and burst rapidly, increase in volume, and form a loose porous structure inside. The specific surface area of ​​the structure increases, making it easier for microorganisms to attach and multiply in large quantities. During the aerobic fermentation of organic solid waste, the microorganisms have a greater intensity of action, a longer heating rate and a longer duration. Although Comparative Example 2 also uses puffed straw, the reason for its relatively poor fermentation effect is that the puffed straw particles cannot fully adhere to the components such as the strain under its dryness, and cannot be well attached to the puffed straw particles. The particle structure of the straw cannot be fully utilized, resulting in insufficient carbon source provided to the microorganisms, resulting in weak fermentation effect in the later stage.

[0093] The results of Comparative Examples 3 and 4 and Example 1 show that the composite strains in the fermentation auxiliary materials of the present application can play a certain degree of synergistic role, and can magnify each other's advantages in the process of fermenting organic solid waste of the present application, and efficiently decompose starch and easily decomposable organic components in solid waste; it can also change the air permeability and heat preservation capacity of the raw materials to the greatest extent, promote the rapid diffusion and effective utilization of oxygen, accelerate the temperature rise and high temperature maintenance after temperature rise, and achieve efficient sterilization and water vapor evaporation. This is due to the characteristics of the microbial strains themselves.

[0094] Regarding Comparative Examples 5 and 6, the fermentation auxiliary materials under the component ratio of puffed straw particles: strains: starch: adhesive are relatively weak in terms of water content, carbon-nitrogen ratio, oxygen content, etc., and cannot provide a suitable environment for the reproduction and growth of microorganisms during aerobic fermentation. As a result, the fermentation process cannot release a large amount of heat to promote the sterilization and dehydration of solid waste.

[0095] Comparison of Example 7 with Example 1 shows that the addition of the fermentation product recycled material promotes the fermentation effect, the fermentation high temperature lasts longer, and the sterilization effect is better. The results of Comparative Examples 8-9 show that the addition of the fermentation product recycled material obtained by fermentation within a certain fermentation degree has a fermentation effect in promoting the preparation of organic fertilizer. In practice, it is found that when the organic solid waste raw material and the composite biological fermentation auxiliary material are mixed in a mass ratio of 1: 0.1-0.5, the high temperature is continued at 50-70°C for 5-7 days, and the first batch of recycled materials obtained after the entire fermentation cycle of 8-10 days has the best fermentation effect, because the moisture content of the fermentation product is reduced to a certain extent, the harmful components are inactivated, and the organic matter is degraded and stabilized. At the same time, in this process, the microorganisms in the composite biological fermentation auxiliary material have been cultured, so that the fermentation product has a certain dominant strain, among which the effect of fermentation for 9 days is the best.

[0096] The present application overcomes the technical problems in the current market and engineering that the adaptability of auxiliary materials and bacterial agents after addition and the continuous energy supply effect of fermentation are relatively poor, the temperature rise after addition is not obvious, the duration is short, the high temperature cannot be maintained, and the dehydration effect is poor.

[0097] Furthermore, the present application also tested the indexes of the organic fertilizers prepared in Examples 1-4 and Comparative Examples 1-9, and applied the organic fertilizers prepared in Examples 1-4 and Comparative Examples 1-9 to the soil to observe the effect of the organic fertilizers on the growth of plants. The specific results are shown in Table 1 below.

[0098] Nitrogen, phosphorus and potassium content detection method:

[0099] According to the provisions of "Organic Fertilizer" (NY 525-2021), the mass fraction of total nutrients (total nitrogen + total phosphorus + total potassium) is calculated on a drying basis. Therefore, when determining the content of total nitrogen, phosphorus, potassium, etc. in organic fertilizers, the sample should be tested for drying moisture at the same time, and the drying moisture should be deducted from the calculation results. The determination methods of total nitrogen, phosphorus, potassium and moisture are all determined in accordance with the methods specified in the standard "Organic Fertilizer" (NY 525-2021) issued by the Ministry of Agriculture.

[0100] A pot test was conducted, with 10 kg of air-dried soil in each bucket. A total of 13 treatments were set up (corresponding to Examples 1-4 and Comparative Examples 1-9, respectively), with 3 replicates for each treatment, and sampling and analysis were performed at the seedling stage, flowering stage, early fruiting stage, and late fruiting stage of the plants, respectively.

[0101] The plants that can be fertilized include roses and crape myrtles, but are not limited to these.

[0102] Table 2 Organic fertilizer detection

[0103]

[0104] According to the data in Table 2 above, compared with Example 5 and Comparative Examples 1-9, the organic fertilizer prepared in Example 1-4 has higher organic matter content, nitrogen, phosphorus and potassium content, better sterilization effect, and the sterilization rate is basically above 96%; the carbon-nitrogen ratio of the product is reduced to 15:1 or below, the degree of stabilization is high, and the land application is safe. The technical problems of slow heating rate, short high temperature period and sterilization effect in the aerobic fermentation process of the prior art are overcome. The shortcomings of poor product quality after aerobic fermentation in the prior art are overcome.

[0105] After the organic fertilizer prepared in the present application is applied, the plants show excellent growth trends in all growth stages.

[0106] The above is only the embodiment of the present application, and the protection scope of the present application is not limited by these specific embodiments, but is determined by the claims of the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the technical ideas and principles of the present application should be included in the protection scope of the present application.

Claims

1. A fermentation method for organic fertilizer, It is characterized in that The steps include: S1. Preparation of fermentation excipients: Step 1: Using straw as a base, crushing it into particles; treating it under high temperature and high pressure to obtain expanded straw particles; Step 2: Dry the puffed straw particles at 70-80°C to 20-30%; Step 3: Add composite bacteria, starch and adhesive to the dried puffed straw particles, and mix them evenly to obtain composite biological fermentation auxiliary materials; The composite bacteria is obtained by compounding the following components in parts by weight: 50-60 parts of actinomycetes, 50-60 parts of bacillus, 2 parts of nitrogen-fixing bacteria, 0-1 part of Trichoderma, 0-1 part of yeast, and 0-1 part of lactic acid bacteria; The weight ratio of puffed straw shreds: starch: bacteria: adhesive = (8.5-9.2): (0.2-0.8): (0.1-0.3): (0.1-0.3); S2. Mix the organic solid waste raw material with the composite biological fermentation auxiliary material and the fermentation product recycled material in a mass ratio of 1: (0.1-0.2): (0.1-0.55), and continue fermenting at 50-70°C for 5-7 days; Among them, in step S2, the fermentation product recycled material is a composite biological fermentation auxiliary material containing undecomposed and cultured dominant bacteria; the fermentation product recycled material is prepared by the following method: the organic solid waste raw material and the composite biological fermentation auxiliary material are mixed in a mass ratio of 1:0.1-0.5, and fermented at 50-70°C for 8-10 days.

2. A method for fermenting organic fertilizer according to claim 1, It is characterized in that In step S2, the organic solid waste raw material is livestock and poultry manure, including pig manure, chicken manure, cow manure, sheep manure and duck manure.

3. A fermentation method for organic fertilizer according to claim 1, It is characterized in that In step 1, the particles are crushed into 1-5 cm particles.

4. A fermentation method for organic fertilizer according to claim 1, It is characterized in that In step 1, the temperature condition is 120-180° C. and the pressure condition is 0.5-1.5 MPa.

5. A fermentation method for organic fertilizer according to claim 1, It is characterized in that The adhesive in step three includes bentonite, urea-formaldehyde resin and epoxy resin.

6. The organic fertilizer prepared by the fermentation method of an organic fertilizer as claimed in claim 1.

7. Application of the organic fertilizer as claimed in claim 6 in soil fertilization.

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