Biological fertilizer for improving soil nutrients and preparation method thereof

Abstract

The invention discloses a biological fertilizer for increasing soil nutrients, which is prepared by mixing a compound bacterial fertilizer, charcoal, polymerized bentonite, calcium superphosphate, straw and livestock manure according to a mass ratio of (8-10): (15-20): (25-35): (5-8): (20-30): (20-30), and the compound bacterial fertilizer is prepared from nitrogen-fixing bacteria, phosphate solubilizing bacteria, growth-promoting bacteria and potassium bacteria by adopting a co-culture system. The polymerized bentonite is prepared by mixing bentonite modified by a salt compound solution rich in cationic groups and a biopolymer; according to the invention, fermentation culture is carried out by adopting a multi-strain co-culture method, and then raw materials such as polymerized bentonite are mixed to prepare the biological fertilizer, so that the conversion rate of nutrients and the content of bioactive substances can be improved, and the content of soil nutrients is improved to promote plant growth; the polymerized bentonite can improve the water retention rate of the soil, greatly alleviate the loss of nutrients in the soil, realize efficient slow release of the fertilizer nutrients and effectively improve the barren soil.

Description

Technical Field

[0001] The present invention relates to the technical field of biofertilizers, and in particular to a biofertilizer for improving soil nutrients and a preparation method thereof. Background Art

[0002] With the development of modern agriculture, soil nutrient management and the improvement of fertilizer utilization efficiency have become increasingly important. Biofertilizer is a type of fertilizer product that uses the life activities of microorganisms as its core to enable crops to obtain specific fertilizer effects.

[0003] Traditional biofertilizers have limited effects on improving soil nutrients. At the same time, traditional fertilizers cannot meet the requirements of soil improvement. For some barren lands, due to soil properties, nutrients are lost quickly and the available land for agriculture and forestry is greatly reduced. Therefore, the present invention proposes a biofertilizer for improving soil nutrients and a preparation method thereof to solve the problems existing in the prior art. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to propose a biological fertilizer for improving soil nutrients and a preparation method thereof. The biological fertilizer for improving soil nutrients and the preparation method thereof are fermented and cultured by a method of co-cultivating multiple strains, and then mixed with raw materials such as polymer bentonite to prepare the biological fertilizer. After co-cultivation of multiple strains, spreading can improve the nutrient conversion rate and the content of biologically active substances, effectively improve the soil nutrient content and promote plant growth; polymer bentonite can greatly slow down the loss of nutrients in the soil while improving the soil water retention rate, and can achieve efficient slow release of fertilizer nutrients, effectively improving poor soil, and is worthy of promotion.

[0005] To achieve the purpose of the present invention, the present invention is achieved through the following technical scheme: a biological fertilizer for improving soil nutrients and a preparation method thereof, comprising a mixture of composite bacterial fertilizer, biochar, polymerized bentonite, superphosphate, straw and livestock manure, wherein the mass ratio of the composite bacterial fertilizer, biochar, polymerized bentonite, superphosphate, straw and livestock manure is 8-10:15-20:25-35:5-8:20-30:20-30, the composite bacterial fertilizer is prepared by a co-culture system of nitrogen-fixing bacteria, phosphate-solubilizing bacteria, growth-promoting bacteria and potassium-solubilizing bacteria, and the polymerized bentonite is prepared by mixing bentonite modified by a salt compound solution rich in cationic groups with a biopolymer.

[0006] A further improvement is that the salt compound rich in cationic groups is one or more of ammonium salts, calcium salts and potassium salts, and the biopolymer is one of guar gum and xanthan gum.

[0007] A method for preparing a biological fertilizer for improving soil nutrients comprises the following steps:

[0008] Step 1: Preparation of fermentation substrate: sterilize and clean the straw, then dry the straw and livestock manure, crush and mix them to obtain a fermentation substrate;

[0009] Step 2, preparation of composite bacterial fertilizer, mixing nitrogen-fixing bacteria, phosphate-dissolving bacteria, growth-promoting bacteria and potassium-dissolving bacteria into a fermentation substrate, sprinkling water to soak it, and performing heat preservation and fermentation treatment to obtain composite bacterial fertilizer;

[0010] Step 3, preparation of polymerized bentonite, mixing the salt compound rich in cationic groups with bentonite, stirring and drying and grinding to obtain bentonite powder, and then stirring and mixing the bentonite powder with a biopolymer to obtain polymerized bentonite;

[0011] Step 4: Preparing prefabricated fertilizers, pretreating the composite fertilizer, and then mixing it with biochar and superphosphate to obtain prefabricated fertilizers;

[0012] Step 5: Mixing and granulation treatment: the prefabricated fertilizer and polymerized bentonite are fully mixed and stirred, and then granulated and dried to obtain biofertilizer.

[0013] The further improvement is that: in the step 2, the fermentation substrate is fully soaked with water before mixing, and then the bacteria are added to be fully mixed and stirred, and water is added in small amounts and multiple times during mixing to control the moisture content of the mixture to be between 60% and 70%, and then the mixture is covered with a film and allowed to ferment; wherein the fermentation conditions are to control the temperature to be between 40 and 50°C, replenish water in time when the moisture content decreases during fermentation, and then control the pH value to be between 6 and 8, and when the fermentation temperature rises above a predetermined temperature, the film is uncovered for ventilation and cooling.

[0014] A further improvement is that the specific preparation in step 3 includes:

[0015] S1, first use deionized water and bentonite obtained by nano-grinding to mix and purify to obtain a slurry for use, and dissolve the salt compound rich in cationic groups in deionized water to obtain a compound solution for use;

[0016] S2, then mixing the slurry with the compound solution, stirring, evaporating, drying and grinding to obtain bentonite powder;

[0017] S3. Add deionized water to the biopolymer in batches and stir to obtain a viscous substance, and then stir and mix the bentonite powder and the viscous substance to obtain polymerized bentonite.

[0018] A further improvement is that the mass ratio of the biopolymer to deionized water in S3 is 2:3, and the biopolymer is added to the mixture in multiple portions and mixed under heating conditions at 60-80°C in a water bath.

[0019] A further improvement is that the pretreatment of the composite bacterial fertilizer in step 4 is to dry the composite bacterial fertilizer prepared in step 2, and then crush and grind it to obtain a large-particle powder of the composite bacterial fertilizer; the mixed superphosphate is finely ground and passed through a 120-mesh sieve to obtain superphosphate powder, which is then mixed with biochar and the large-particle powder of the composite bacterial fertilizer to obtain a prefabricated fertilizer.

[0020] A further improvement is that when the prefabricated fertilizer is mixed with the polymerized bentonite in step 5, the prefabricated fertilizer is added in multiple times, and each time a certain amount of prefabricated fertilizer is added, it is fully stirred for 10-20 minutes, and the moisture content of the mixture is kept between 45% and 55% while stirring.

[0021] The beneficial effects of the present invention are as follows: the present invention adopts multiple strains for co-fermentation culture, and then mixes them with raw materials such as polymer bentonite to prepare biological fertilizers. After the multiple strains are co-cultivated and spread, the nutrient conversion rate and the content of biologically active substances can be improved, and the nutrient content of the soil can be effectively increased to promote plant growth; the polymer bentonite can greatly slow down the loss of nutrients in the soil while improving the soil water retention rate, and can achieve efficient slow release of fertilizer nutrients, effectively improving poor soil, and is worthy of promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0023] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0024] Example 1

[0025] The present embodiment provides a biological fertilizer for improving soil nutrients, including a compound bacterial fertilizer, biochar, polymerized bentonite, superphosphate, straw and livestock manure mixed in a mass ratio of 10:15:30:5:20:20, the compound bacterial fertilizer is prepared by mixing nitrogen-fixing bacteria, phosphate-solubilizing bacteria, growth-promoting bacteria and potassium-solubilizing bacteria in a co-culture system in a weight ratio of 1:1.2:0.6:1.1, and the polymerized bentonite is prepared by mixing bentonite modified by a potassium salt solution with xanthan gum.

[0026] according to Figure 1 As shown, this embodiment provides a method for preparing a biological fertilizer for improving soil nutrients, comprising the following steps:

[0027] Step 1: Preparation of fermentation substrate: sterilize and clean the straw first, then dry the straw and livestock manure, crush and mix them to obtain the fermentation substrate.

[0028] Step 2, preparation of composite bacterial fertilizer, mixing nitrogen-fixing bacteria, phosphate-dissolving bacteria, growth-promoting bacteria and potassium-dissolving bacteria into a fermentation substrate, sprinkling water to soak it, and performing heat preservation and fermentation treatment to obtain composite bacterial fertilizer;

[0029] The fermentation substrate is fully soaked with water before mixing, and then the bacteria are added to mix and stir thoroughly. Water is added in small amounts and multiple times during mixing to control the moisture content of the mixture between 60% and 70%, and then the mixture is covered with a film and allowed to ferment. The fermentation conditions are as follows: the temperature is controlled between 40 and 50°C, water is added in time when the moisture content decreases during fermentation, and the pH value is controlled between 6 and 8. When the fermentation temperature rises above a predetermined temperature, the film is uncovered for ventilation and cooling.

[0030] Step 3, preparation of polymerized bentonite, mixing potassium salt and bentonite, and drying and grinding to obtain bentonite powder, and then mixing the bentonite powder with xanthan gum to obtain polymerized bentonite, wherein the mass ratio of potassium salt, bentonite and xanthan gum is 10:55:35; the specific preparation includes:

[0031] S1. First, deionized water and bentonite obtained by nano-grinding are mixed and purified to obtain a slurry for standby use, and potassium salt is dissolved in deionized water to obtain a compound solution for standby use;

[0032] S2, then mixing the slurry with the compound solution, stirring, evaporating, drying and grinding to obtain bentonite powder;

[0033] S3. Add deionized water to the xanthan gum in batches and stir to obtain a viscous substance, and then stir and mix the bentonite powder and the viscous substance to obtain polymerized bentonite; wherein the mass ratio of xanthan gum to deionized water is 2:3, and the mixture is added in multiple times and mixed under heating conditions at 60-80°C in a water bath.

[0034] Step 4: Preparing prefabricated fertilizers, drying the composite bacterial fertilizers prepared in step 2, and then crushing and grinding them to obtain large-particle powders of the composite bacterial fertilizers, and then mixing and stirring the powders with biochar and superphosphate to obtain prefabricated fertilizers;

[0035] The mixed superphosphate is finely ground and passed through a 120-mesh sieve to obtain superphosphate powder, which is then mixed with biochar and composite bacterial fertilizer large particle powder.

[0036] Step 5: Mixing and granulating the prefabricated fertilizer and the polymerized bentonite, and then granulating and drying to obtain the biofertilizer;

[0037] When the prefabricated fertilizer is mixed with the polymerized bentonite, the prefabricated fertilizer is added in multiple times. After each addition of a certain amount of the prefabricated fertilizer, it is fully stirred for 20 minutes, and the water content of the mixture is kept between 45% and 55% while stirring.

[0038] Example 2

[0039] The present embodiment provides a biological fertilizer for improving soil nutrients, including a mixture of compound bacterial fertilizer, biochar, polymerized bentonite, superphosphate, straw and livestock manure in a mass ratio of 10:17:25:8:20:20, wherein the compound bacterial fertilizer is prepared by mixing nitrogen-fixing bacteria, phosphate-solubilizing bacteria, growth-promoting bacteria and potassium-solubilizing bacteria in a co-culture system in a weight ratio of 1:1.2:0.6:1.1, and the polymerized bentonite is prepared by mixing bentonite modified by an ammonium salt solution with guar gum.

[0040] according to Figure 1 As shown, this embodiment provides a method for preparing a biological fertilizer for improving soil nutrients, comprising the following steps:

[0041] Step 1: Preparation of fermentation substrate: sterilize and clean the straw first, then dry the straw and livestock manure, crush and mix them to obtain the fermentation substrate.

[0042] Step 2, preparation of composite bacterial fertilizer, mixing nitrogen-fixing bacteria, phosphate-dissolving bacteria, growth-promoting bacteria and potassium-dissolving bacteria into a fermentation substrate, sprinkling water to soak it, and performing heat preservation and fermentation treatment to obtain composite bacterial fertilizer;

[0043] The fermentation substrate is fully soaked with water before mixing, and then the bacteria are added to mix and stir thoroughly. Water is added in small amounts and multiple times during mixing to control the moisture content of the mixture between 60% and 70%, and then the mixture is covered with a film and allowed to ferment. The fermentation conditions are as follows: the temperature is controlled between 40 and 50°C, water is added in time when the moisture content decreases during fermentation, and the pH value is controlled between 6 and 8. When the fermentation temperature rises above a predetermined temperature, the film is uncovered for ventilation and cooling.

[0044] Step 3, preparation of polymerized bentonite, mixing ammonium salt and bentonite, and drying and grinding to obtain bentonite powder, and then mixing the bentonite powder with xanthan gum to obtain polymerized bentonite, wherein the mass ratio of ammonium salt, bentonite and xanthan gum is 8:52:40; the specific preparation includes:

[0045] S1, first use deionized water and bentonite obtained by nano-grinding to mix and purify to obtain a slurry for use, and dissolve the ammonium salt in deionized water to obtain a compound solution for use;

[0046] S2, then mixing the slurry with the compound solution, stirring, evaporating, drying and grinding to obtain bentonite powder;

[0047] S3, adding deionized water to guar gum in batches and stirring to obtain a viscous substance, and then stirring and mixing the bentonite powder and the viscous substance to obtain polymerized bentonite; wherein the mass ratio of guar gum to deionized water is 2:3, and when adding the mixture, adding it in multiple times and mixing under heating conditions of 60-80°C in a water bath.

[0048] Step 4: Preparing prefabricated fertilizers, drying the composite bacterial fertilizers prepared in step 2, and then crushing and grinding them to obtain large-particle powders of the composite bacterial fertilizers, and then mixing and stirring the powders with biochar and superphosphate to obtain prefabricated fertilizers;

[0049] The mixed superphosphate is finely ground and passed through a 120-mesh sieve to obtain superphosphate powder, which is then mixed with biochar and composite bacterial fertilizer large particle powder.

[0050] Step 5: Mixing and granulating the prefabricated fertilizer and the polymerized bentonite, and then granulating and drying to obtain the biofertilizer;

[0051] When the prefabricated fertilizer is mixed with the polymerized bentonite, the prefabricated fertilizer is added in multiple times. After each addition of a certain amount of the prefabricated fertilizer, it is fully stirred for 20 minutes, and the water content of the mixture is kept between 45% and 55% while stirring.

[0052] In order to verify the fertilization effect of the biological fertilizer prepared in the present application, the biological fertilizer prepared in Example 1 and Example 2 and the traditional biological fertilizer (Genliduo) were subjected to soil fertilization and planting experiments. Cherry tomatoes were taken as an example of the planted crop. The same amount of fertilizer was applied to equal areas of soil during the application, and soil fertility was tested 5 days, 10 days, 20 days and 30 days after the application. The soil fertility test included fertilizer release rate detection and plant growth record. The growth record was the plant height. The results are shown in the table below.

[0053] Soil fertility testing

[0054]

[0055] As can be seen from the above table, from the plant growth data, it can be seen that the biofertilizer of the present application effectively improves soil fertility after adding different kinds of biological flora, and the growth is better than traditional biofertilizers. At the same time, it is better than the addition of polymerized bentonite, which delays the release rate of fertilizers and reduces the rate of nutrient loss after fertilization, which makes the plant growth increase at a uniform rate. After fertilization with traditional biofertilizers, the plant growth grows rapidly in the first 10 days, and the growth rate decreases significantly in the following time. This is closely related to the fertility release rate and nutrient loss rate in the soil. It indirectly shows that the biofertilizer prepared in the present application can also reduce the rate of nutrient loss in soil fertilization, so that the fertilization nutrients can be maintained for a longer time.

[0056] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A biological fertilizer for improving soil nutrients, characterized by: The invention comprises a mixture of compound bacterial fertilizer, biochar, polymerized bentonite, superphosphate, straw and livestock manure, wherein the mass ratio of the compound bacterial fertilizer, biochar, polymerized bentonite, superphosphate, straw and livestock manure is 8-10:15-20:25-35:5-8:20-30:20-30; the compound bacterial fertilizer is prepared by a co-culture system of nitrogen-fixing bacteria, phosphate-solubilizing bacteria, growth-promoting bacteria and potassium-solubilizing bacteria; the polymerized bentonite is prepared by mixing bentonite modified by a salt compound solution rich in cationic groups with a biopolymer.

2. The biological fertilizer for improving soil nutrients according to claim 1, characterized in that: The salt compound rich in cationic groups is one or more of ammonium salt, calcium salt and potassium salt, and the biopolymer is one of guar gum and xanthan gum.

3. A method for preparing a biological fertilizer for improving soil nutrients, characterized in that: The following steps are involved: Step 1: Preparation of fermentation substrate: sterilize and clean the straw, then dry the straw and livestock manure, crush and mix them to obtain a fermentation substrate; Step 2, preparation of composite bacterial fertilizer: nitrogen-fixing bacteria, phosphate-dissolving bacteria, growth-promoting bacteria and potassium-dissolving bacteria are mixed into a fermentation substrate, sprinkled with water to soak it, and subjected to heat preservation and fermentation treatment to obtain a composite bacterial fertilizer; Step 3, preparation of polymerized bentonite: mixing the salt compound rich in cationic groups with bentonite, stirring and drying and grinding to obtain bentonite powder, and then stirring and mixing the bentonite powder with a biopolymer to obtain polymerized bentonite; Step 4: Preparing prefabricated fertilizer: pretreating the composite fertilizer, and then mixing it with biochar and superphosphate to obtain prefabricated fertilizer; Step 5: Mixing and granulation: The prefabricated fertilizer and polymerized bentonite are fully mixed and stirred, and then granulated and dried to obtain the biofertilizer.

4. The method for preparing a biological fertilizer for improving soil nutrients according to claim 3, characterized in that: In the step 2, the fermentation substrate is fully soaked with water before mixing, and then the bacteria are added to be fully mixed and stirred. During mixing, water is added in small amounts and multiple times to control the moisture content of the mixture to be between 60% and 70%, and then the mixture is covered with a film and allowed to ferment. The fermentation conditions are as follows: the temperature is controlled between 40 and 50° C., water is replenished in time when the moisture content decreases during fermentation, and the pH value is controlled between 6 and 8. When the fermentation temperature rises above a predetermined temperature, the film is uncovered for ventilation and cooling.

5. The method for preparing a biological fertilizer for improving soil nutrients according to claim 3, characterized in that: The specific preparation in step 3 includes S1, first use deionized water and bentonite obtained by nano-grinding to mix and purify to obtain a slurry for use, and dissolve the salt compound rich in cationic groups in deionized water to obtain a compound solution for use; S2, then mixing the slurry with the compound solution, stirring, evaporating, drying and grinding to obtain bentonite powder; S3. Add deionized water to the biopolymer in batches and stir to obtain a viscous substance, and then stir and mix the bentonite powder and the viscous substance to obtain polymerized bentonite.

6. The method for preparing a biological fertilizer for improving soil nutrients according to claim 5, characterized in that: The mass ratio of the biopolymer to deionized water in S3 is 2:

3. When adding the biopolymer to the mixture, the biopolymer is added in multiple times and mixed under heating conditions at 60-80° C. in a water bath.

7. The method for preparing a biological fertilizer for improving soil nutrients according to claim 3, characterized in that: The pretreatment of the composite bacterial fertilizer in step 4 is to dry the composite bacterial fertilizer prepared in step 2, and then crush and grind it to obtain large-particle powder of the composite bacterial fertilizer; the mixed superphosphate is finely ground and passed through a 120-mesh sieve to obtain superphosphate powder, which is then mixed with biochar and the large-particle powder of the composite bacterial fertilizer to obtain prefabricated fertilizer.

8. The method for preparing a biological fertilizer for improving soil nutrients according to claim 3, characterized in that: In the step 5, when the prefabricated fertilizer is mixed with the polymerized bentonite, the prefabricated fertilizer is added in multiple times. After each addition of a certain amount of prefabricated fertilizer, it is fully stirred for 10-20 minutes, and the moisture content of the mixture is kept between 45% and 55% while stirring.

Images