Slow-release microbial fertilizer for improving saline-alkali soil and preparation method of slow-release microbial fertilizer

Abstract

The invention provides a slow-release microbial fertilizer for improving saline-alkali soil and a preparation method of the slow-release microbial fertilizer. The microbial fertilizer is prepared from the following components in parts by weight: 100 to 150 parts of urea, 40 to 50 parts of crop straw, 3 to 9 parts of biochemical fulvic acid, 8 to 20 parts of chitosan / gelatin composite hydrogel, 10 to 20 parts of wormcast, 4 to 12 parts of desulfurized gypsum, 1 to 4 parts of microbial agent, 2 to 8 parts of nano humic acid, 12 to 22 parts of nano diatomite and 2 to 8 parts of soil conditioner. The prepared slow-release microbial fertilizer has the effects of promoting crop growth, improving the soil quality of saline-alkali soil and increasing the organic matter content of the soil, can better regulate the physical and chemical properties of the soil, and can inhibit harmful bacteria, enrich the diversity of beneficial bacteria and quickly improve the soil structure.

Description

Technical Field

[0001] The present application relates to the technical field of preparation of microbial fertilizers, and in particular to a slow-release microbial fertilizer for improving saline-alkali land and a preparation method thereof. Background Art

[0002] According to the degree of salinity, saline-alkali land can be divided into severe salinity, moderate salinity, and light and severe salinity, that is, the salt content is 0.4%-0.6%, 0.2%-0.4%, and 0.1-0.2%. According to the pH value of the land, 6.5-7.5 is mild, 7.5-8.5 is moderate, and more than 8.5 is severe. Saline-alkali land is a type of salt accumulation, which means that the salt contained in the soil affects the normal growth of crops. Various saline-alkali soils are formed under certain natural conditions. The essence of their formation is mainly the horizontal and vertical redistribution of various soluble salts on the ground, so that salt gradually accumulates on the surface of the soil in the salt-accumulating area.

[0003] The fundamental reason for the formation of saline-alkali soil is the poor water conditions. The improvement of saline-alkali land is generally carried out in the following steps: first, drain the salt, wash the salt, and reduce the salt content of the soil; then plant salt-alkali tolerant plants and fertilize the soil; finally plant crops. Specific improvement measures are: drainage, irrigation and salt washing, silt release and improvement, crop planting, fertilization and improvement, land leveling and chemical improvement. In the early stage of improvement, the focus should be on improving the water conditions of the soil. It is generally carried out in several steps: first, drain the salt, wash the salt, and reduce the salt content of the soil; then plant salt-alkali tolerant plants and fertilize the soil; finally plant crops. Specific improvement measures are: drainage, irrigation and salt washing, silt release and improvement, rice planting, fertilization and improvement, land leveling and chemical improvement.

[0004] Microbial fertilizer contains more than ten kinds of highly efficient and active beneficial microorganisms. It is suitable for various crops, can activate nutrients, improve nutrient utilization, and is widely used. It breaks the inherent weaknesses of "specificity", "limitation" and "special fertilizer" of ordinary biological fertilizers, which is unmatched by other biological fertilizers. It can be applied to various types of soil. Generally speaking, any land where plants grow can be applied with microbial fertilizers to improve the soil and reduce the use of chemical fertilizers to promote crop growth. It helps to return the soil to its natural state and balance the pH value of the soil to the level required by crops. All of this is to help improve soil fertility and help eliminate pollution in soil, water and atmosphere. The current microbial fertilizers contain less beneficial colonies, a large amount of fertilizer is used, and the soil improvement effect is poor. Therefore, it is necessary to produce a slow-release microbial fertilizer for improving saline-alkali land. Summary of the invention

[0005] The present application provides a slow-release microbial fertilizer for improving saline-alkali land and a preparation method thereof, so as to solve the problems of poor soil improvement effect and low efficiency of microbial fertilizers in the prior art, achieve the effects of promoting crop growth, improving saline-alkali land soil quality and increasing the organic matter content of the land, and can better regulate the physical and chemical properties of the soil.

[0006] The present application provides a slow-release microbial fertilizer for improving saline-alkali land. The components of the microbial fertilizer include, by weight, 100-150 parts of urea, 40-50 parts of crop straw, 3-9 parts of biochemical fulvic acid, 8-20 parts of chitosan / gelatin composite hydrogel, 10-20 parts of earthworm castings, 4-12 parts of desulfurized gypsum, 1-4 parts of microbial agent, 2-8 parts of nano-humic acid, 12-22 parts of nano-diatomaceous earth, and 2-8 parts of soil conditioner.

[0007] Preferably, the microbial fertilizer components include, by weight, 125 parts of urea, 45 parts of crop straw, 6 parts of biochemical fulvic acid, 14 parts of chitosan / gelatin composite hydrogel, 15 parts of earthworm castings, 8 parts of desulfurized gypsum, 3 parts of microbial agent, 5 parts of nano humic acid, 18 parts of nano diatomaceous earth, and 5 parts of soil conditioner.

[0008] Preferably, the crop straw is a mixture of corn straw, rape straw, rice straw, peanut straw, wheat straw, soybean straw and sorghum straw.

[0009] Preferably, the microbial agent components include 10-20 parts of Bacillus subtilis powder, 10-20 parts of Bacillus subtilis powder, 5-15 parts of Bacillus licheniformis powder, 4-12 parts of silicate bacteria powder, 4-12 parts of salt-tolerant Brazilian Azospirillum powder, 4-10 parts of Lactobacillus rhamnosus powder, and 2-6 parts of Enterococcus faecalis powder by weight.

[0010] Preferably, the bacterial count of each bacterial powder in the microbial agent is 1.5×10 8 cfu / g-2.5×10 8 cfu / g.

[0011] Preferably, the soil conditioner is composed of 40% bamboo biochar, 40% selenium-rich carbonaceous shale powder, 15% wood vinegar, 3% halophilic Exothiorhodospirillum, and 2% acidobacterium.

[0012] Preferably, a method for preparing a slow-release microbial fertilizer for improving saline-alkali land comprises the following steps:

[0013] A. First, the crop straw is added into a grinder and crushed, and then sieved to obtain straw powder;

[0014] B. Add earthworm castings, desulfurized gypsum, biochemical fulvic acid, nano humic acid and nano diatomaceous earth to the straw powder, mix thoroughly, add to a stirring tank and stir in sections to obtain a mixture A;

[0015] C. Inoculating the microbial agent into the solid fermentation medium, culturing at a certain temperature for a period of time, and obtaining the solid fermentation medium agent;

[0016] D. Then, in a mixing tank, mixture A, chitosan / gelatin composite hydrogel, soil conditioner and solid fermentation medium bacterial agent are added in sequence, fully stirred and mixed at room temperature, and sealed and stored for 3-5 days to obtain a semi-finished microbial fertilizer;

[0017] E. Finally, add the semi-finished microbial product into the granulator to make a slow-release microbial fertilizer.

[0018] Preferably, in step A, the rotation speed of the pulverizer is 2000-4000 rpm, the pulverizing time is 50 min-70 min, and the fineness of the straw powder after pulverization is 200-400 mesh.

[0019] Preferably, in step B, low-speed stirring is first adopted, with a stirring rate of 200-400 rpm, and after stirring for 10 min, high-speed stirring is adopted, with a stirring rate of 5000-8000 rpm, and the stirring time is 30 min-50 min.

[0020] Preferably, in step C, the culture temperature is 32° C.-35° C., and the culture time is 2-3 days.

[0021] Beneficial effects:

[0022] (1) The preparation method of the present invention is simple, and the obtained slow-release microbial fertilizer has the effects of promoting crop growth, improving saline-alkali soil quality and increasing the organic matter content of the land, and can better regulate the physical and chemical properties of the soil. At the same time, it can also inhibit harmful bacteria, enrich the diversity of beneficial bacteria, and quickly improve the soil structure.

[0023] (2) The microbial agent added in the present invention contains a large amount of ammonia-fixing bacteria, potassium-dissolving bacteria, and antibiotics, which can effectively supplement the nutrients required for crops at various growth stages, inhibit the growth of various pathogens and pests remaining in the soil, promote the circulation of nutrients such as carbon, nitrogen, phosphorus, and sulfur, and enrich the diversity of dominant bacterial flora in the soil.

[0024] (3) The soil conditioner added in the present invention can better regulate the physical and chemical properties of the soil, adjust the soil pH, prevent the soil from becoming compacted, and effectively avoid the re-accumulation of salt through the synergistic effect of bamboo biochar, selenium-rich carbonaceous shale powder and bacterial colonies.

[0025] (4) The preparation method adopted by the present invention can promote the full mixing of various materials. In addition, the microbial agent is inoculated into the solid fermentation medium to prepare the solid fermentation medium agent, which can play a role in gathering nutrients and beneficial microorganisms, thereby making the soil fertile and conducive to plant growth.

[0026] The above description is only an overview of the technical solution of the embodiment of the present application. In order to more clearly understand the technical means of the embodiment of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of the application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0029] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase "embodiments" in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0030] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application is clearly and completely described below.

[0031] The present application provides a slow-release microbial fertilizer for improving saline-alkali land. The components of the microbial fertilizer include, by weight, 100-150 parts of urea, 40-50 parts of crop straw, 3-9 parts of biochemical fulvic acid, 8-20 parts of chitosan / gelatin composite hydrogel, 10-20 parts of earthworm castings, 4-12 parts of desulfurized gypsum, 1-4 parts of microbial agent, 2-8 parts of nano-humic acid, 12-22 parts of nano-diatomaceous earth, and 2-8 parts of soil conditioner.

[0032] Embodiment 1:

[0033] The microbial fertilizer components include, by weight, 100 parts of urea, 40 parts of crop straws, 3 parts of biochemical fulvic acid, 8 parts of chitosan / gelatin composite hydrogel, 10 parts of earthworm castings, 4 parts of desulfurized gypsum, 1 part of microbial agent, 2 parts of nano humic acid, 12 parts of nano diatomaceous earth, and 2 parts of soil conditioner.

[0034] In this embodiment, the crop straw is a mixture of corn straw, rape straw, rice straw, peanut straw, wheat straw, soybean straw and sorghum straw.

[0035] In this embodiment, the microbial agent components include 10 parts of Bacillus subtilis powder, 10 parts of Bacillus subtilis powder, 5 parts of Bacillus licheniformis powder, 4 parts of silicate bacteria powder, 4 parts of salt-tolerant Brazilian Azospirillum powder, 4 parts of Lactobacillus rhamnosus powder, and 2 parts of Enterococcus faecalis powder in parts by weight.

[0036] In this embodiment, the bacterial count of each bacterial powder in the microbial inoculant is 1.5×10 8 cfu / g.

[0037] In this embodiment, the soil conditioner is composed of 40% bamboo biochar, 40% selenium-rich carbonaceous shale powder, 15% wood vinegar, 3% halophilic Exothiorhodospirillum, and 2% acidobacterium.

[0038] In this embodiment, a method for preparing a slow-release microbial fertilizer for improving saline-alkali land comprises the following steps:

[0039] A. First, the crop straw is added into a grinder and crushed, and then sieved to obtain straw powder;

[0040] B. Add earthworm castings, desulfurized gypsum, biochemical fulvic acid, nano humic acid and nano diatomaceous earth to the straw powder, mix thoroughly, add to a stirring tank and stir in sections to obtain a mixture A;

[0041] C. Inoculating the microbial agent into the solid fermentation medium, culturing at a certain temperature for a period of time, and obtaining the solid fermentation medium agent;

[0042] D. Then, mixture A, chitosan / gelatin composite hydrogel, soil conditioner and solid fermentation medium bacterial agent were added to a mixing tank in sequence, fully stirred and mixed at room temperature, and sealed and stored for 3 days to obtain a semi-finished microbial fertilizer;

[0043] E. Finally, add the semi-finished microbial product into the granulator to make a slow-release microbial fertilizer.

[0044] In this embodiment, the rotation speed of the pulverizer in step A is 2000 rpm, the pulverizing time is 50 min, and the fineness of the straw powder after pulverization is 200 mesh.

[0045] In this embodiment, in step B, low-speed stirring is first adopted, the stirring rate is 200 rpm, and after stirring for 10 minutes, high-speed stirring is adopted, the stirring rate is 5000 rpm, and the stirring time is 30 minutes.

[0046] In this embodiment, the culture temperature in step C is 32° C. and the culture time is 2 days.

[0047] Embodiment 2:

[0048] The microbial fertilizer components include 150 parts of urea, 50 parts of crop straw, 9 parts of biochemical fulvic acid, 20 parts of chitosan / gelatin composite hydrogel, 20 parts of earthworm castings, 12 parts of desulfurized gypsum, 4 parts of microbial agent, 8 parts of nano humic acid, 22 parts of nano diatomaceous earth and 8 parts of soil conditioner by weight.

[0049] In this embodiment, the crop straw is a mixture of corn straw, rape straw, rice straw, peanut straw, wheat straw, soybean straw and sorghum straw.

[0050] In this embodiment, the microbial agent components include 20 parts of Bacillus subtilis powder, 20 parts of Bacillus subtilis powder, 15 parts of Bacillus licheniformis powder, 12 parts of silicate bacteria powder, 12 parts of salt-tolerant Brazilian Azospirillum powder, 10 parts of Lactobacillus rhamnosus powder, and 6 parts of Enterococcus faecalis powder by weight.

[0051] In this embodiment, the bacterial count of each bacterial powder in the microbial inoculant is 2.5×10 8 cfu / g.

[0052] In this embodiment, the soil conditioner is composed of 40% bamboo biochar, 40% selenium-rich carbonaceous shale powder, 15% wood vinegar, 3% halophilic Exothiorhodospirillum, and 2% acidobacterium.

[0053] In this embodiment, a method for preparing a slow-release microbial fertilizer for improving saline-alkali land comprises the following steps:

[0054] A. First, the crop straw is added into a grinder and crushed, and then sieved to obtain straw powder;

[0055] B. Add earthworm castings, desulfurized gypsum, biochemical fulvic acid, nano humic acid and nano diatomaceous earth to the straw powder, mix thoroughly, add to a stirring tank and stir in sections to obtain a mixture A;

[0056] C. Inoculating the microbial agent into the solid fermentation medium, culturing at a certain temperature for a period of time, and obtaining the solid fermentation medium agent;

[0057] D. Then, mixture A, chitosan / gelatin composite hydrogel, soil conditioner and solid fermentation medium bacterial agent were added to a mixing tank in sequence, fully stirred and mixed at room temperature, and sealed and stored for 5 days to obtain a semi-finished microbial fertilizer;

[0058] E. Finally, add the semi-finished microbial product into the granulator to make a slow-release microbial fertilizer.

[0059] In this embodiment, the rotation speed of the pulverizer in step A is 4000 rpm, the pulverizing time is 70 min, and the fineness of the straw powder after pulverization is 400 mesh.

[0060] In this embodiment, in step B, low-speed stirring is first adopted, the stirring rate is 400 rpm, and after stirring for 10 minutes, high-speed stirring is adopted, the stirring rate is 8000 rpm, and the stirring time is 50 minutes.

[0061] In this embodiment, the culture temperature in step C is 35° C. and the culture time is 3 days.

[0062] Embodiment three:

[0063] The microbial fertilizer components include 120 parts of urea, 42 parts of crop straw, 5 parts of biochemical fulvic acid, 10 parts of chitosan / gelatin composite hydrogel, 12 parts of earthworm castings, 6 parts of desulfurized gypsum, 2 parts of microbial agent, 3 parts of nano humic acid, 14 parts of nano diatomaceous earth and 3 parts of soil conditioner by weight.

[0064] In this embodiment, the crop straw is a mixture of corn straw, rape straw, rice straw, peanut straw, wheat straw, soybean straw and sorghum straw.

[0065] In this embodiment, the microbial agent components include 12 parts of Bacillus subtilis powder, 12 parts of Bacillus subtilis powder, 8 parts of Bacillus licheniformis powder, 7 parts of silicate bacteria powder, 6 parts of salt-tolerant Brazilian Azospirillum powder, 9 parts of Lactobacillus rhamnosus powder, and 5 parts of Enterococcus faecalis powder by weight.

[0066] In this embodiment, the bacterial count of each bacterial powder in the microbial inoculant is 1.6×10 8 cfu / g.

[0067] In this embodiment, the soil conditioner is composed of 40% bamboo biochar, 40% selenium-rich carbonaceous shale powder, 15% wood vinegar, 3% halophilic Exothiorhodospirillum, and 2% acidobacterium.

[0068] In this embodiment, a method for preparing a slow-release microbial fertilizer for improving saline-alkali land comprises the following steps:

[0069] A. First, the crop straw is added into a grinder and crushed, and then sieved to obtain straw powder;

[0070] B. Add earthworm castings, desulfurized gypsum, biochemical fulvic acid, nano humic acid and nano diatomaceous earth to the straw powder, mix thoroughly, add to a stirring tank and stir in sections to obtain a mixture A;

[0071] C. Inoculating the microbial agent into the solid fermentation medium, culturing at a certain temperature for a period of time, and obtaining the solid fermentation medium agent;

[0072] D. Then, mixture A, chitosan / gelatin composite hydrogel, soil conditioner and solid fermentation medium bacterial agent were added to a mixing tank in sequence, fully stirred and mixed at room temperature, and sealed and stored for 3 days to obtain a semi-finished microbial fertilizer;

[0073] E. Finally, add the semi-finished microbial product into the granulator to make a slow-release microbial fertilizer.

[0074] In this embodiment, the rotation speed of the pulverizer in step A is 2400 rpm, the pulverizing time is 55 min, and the fineness of the pulverized straw powder is 280 mesh.

[0075] In this embodiment, in step B, low-speed stirring is first adopted, the stirring rate is 240 rpm, and after stirring for 10 min, high-speed stirring is adopted, the stirring rate is 6000 rpm, and the stirring time is 35 min.

[0076] In this embodiment, the culture temperature in step C is 33° C. and the culture time is 2 days.

[0077] Embodiment 4:

[0078] The microbial fertilizer components include 100 parts of urea, 50 parts of crop straws, 3 parts of biochemical fulvic acid, 20 parts of chitosan / gelatin composite hydrogel, 10 parts of earthworm castings, 12 parts of desulfurized gypsum, 1 part of microbial agent, 8 parts of nano humic acid, 12 parts of nano diatomaceous earth and 8 parts of soil conditioner by weight.

[0079] In this embodiment, the crop straw is a mixture of corn straw, rape straw, rice straw, peanut straw, wheat straw, soybean straw and sorghum straw.

[0080] In this embodiment, the microbial agent components include 10 parts of Bacillus subtilis powder, 20 parts of Bacillus subtilis powder, 5 parts of Bacillus licheniformis powder, 12 parts of silicate bacteria powder, 4 parts of salt-tolerant Brazilian Azospirillum powder, 10 parts of Lactobacillus rhamnosus powder, and 2 parts of Enterococcus faecalis powder in parts by weight.

[0081] In this embodiment, the bacterial count of each bacterial powder in the microbial inoculant is 1.7×10 8 cfu / g.

[0082] In this embodiment, the soil conditioner is composed of 40% bamboo biochar, 40% selenium-rich carbonaceous shale powder, 15% wood vinegar, 3% halophilic Exothiorhodospirillum, and 2% acidobacterium.

[0083] In this embodiment, a method for preparing a slow-release microbial fertilizer for improving saline-alkali land comprises the following steps:

[0084] A. First, the crop straw is added into a grinder and crushed, and then sieved to obtain straw powder;

[0085] B. Add earthworm castings, desulfurized gypsum, biochemical fulvic acid, nano humic acid and nano diatomaceous earth to the straw powder, mix thoroughly, add to a stirring tank and stir in sections to obtain a mixture A;

[0086] C. Inoculating the microbial agent into the solid fermentation medium, culturing at a certain temperature for a period of time, and obtaining the solid fermentation medium agent;

[0087] D. Then, mixture A, chitosan / gelatin composite hydrogel, soil conditioner and solid fermentation medium bacterial agent were added to a mixing tank in sequence, fully stirred and mixed at room temperature, and sealed and stored for 5 days to obtain a semi-finished microbial fertilizer;

[0088] E. Finally, add the semi-finished microbial product into the granulator to make a slow-release microbial fertilizer.

[0089] In this embodiment, the speed of the pulverizer in step A is 2000 rpm, the pulverizing time is 70 min, and the fineness of the pulverized straw powder is 200 mesh.

[0090] In this embodiment, in step B, low-speed stirring is first adopted, the stirring rate is 400 rpm, and after stirring for 10 minutes, high-speed stirring is adopted, the stirring rate is 5000 rpm, and the stirring time is 50 minutes.

[0091] In this embodiment, the culture temperature in step C is 32° C. and the culture time is 3 days.

[0092] Embodiment five:

[0093] The microbial fertilizer components include 140 parts of urea, 48 parts of crop straw, 8 parts of biochemical fulvic acid, 18 parts of chitosan / gelatin composite hydrogel, 18 parts of earthworm castings, 10 parts of desulfurized gypsum, 3 parts of microbial agent, 7 parts of nano humic acid, 20 parts of nano diatomaceous earth and 7 parts of soil conditioner by weight.

[0094] In this embodiment, the crop straw is a mixture of corn straw, rape straw, rice straw, peanut straw, wheat straw, soybean straw and sorghum straw.

[0095] In this embodiment, the microbial agent components include 18 parts of Bacillus subtilis powder, 18 parts of Bacillus subtilis powder, 14 parts of Bacillus licheniformis powder, 11 parts of silicate bacteria powder, 10 parts of salt-tolerant Brazilian Azospirillum powder, 9 parts of Lactobacillus rhamnosus powder, and 5 parts of Enterococcus faecalis powder by weight.

[0096] In this embodiment, the bacterial count of each bacterial powder in the microbial inoculant is 2.4×10 8 cfu / g.

[0097] In this embodiment, the soil conditioner is composed of 40% bamboo biochar, 40% selenium-rich carbonaceous shale powder, 15% wood vinegar, 3% halophilic Exothiorhodospirillum, and 2% acidobacterium.

[0098] In this embodiment, a method for preparing a slow-release microbial fertilizer for improving saline-alkali land comprises the following steps:

[0099] A. First, the crop straw is added into a grinder and crushed, and then sieved to obtain straw powder;

[0100] B. Add earthworm castings, desulfurized gypsum, biochemical fulvic acid, nano humic acid and nano diatomaceous earth to the straw powder, mix thoroughly, add to a stirring tank and stir in sections to obtain a mixture A;

[0101] C. Inoculating the microbial agent into the solid fermentation medium, culturing at a certain temperature for a period of time, and obtaining the solid fermentation medium agent;

[0102] D. Then, mixture A, chitosan / gelatin composite hydrogel, soil conditioner and solid fermentation medium bacterial agent were added to a mixing tank in sequence, fully stirred and mixed at room temperature, and sealed and stored for 5 days to obtain a semi-finished microbial fertilizer;

[0103] E. Finally, add the semi-finished microbial product into the granulator to make a slow-release microbial fertilizer.

[0104] In this embodiment, the rotation speed of the pulverizer in step A is 2800 rpm, the pulverizing time is 65 min, and the fineness of the straw powder after pulverization is 320 mesh.

[0105] In this embodiment, in step B, low-speed stirring is first adopted, and the stirring rate is 320 rpm. After stirring for 10 min, high-speed stirring is then adopted, and the stirring rate is 6200 rpm. The stirring time is 38 min.

[0106] In this embodiment, the culture temperature in step C is 34° C. and the culture time is 3 days.

[0107] Embodiment six:

[0108] The microbial fertilizer components include 125 parts of urea, 45 parts of crop straw, 6 parts of biochemical fulvic acid, 14 parts of chitosan / gelatin composite hydrogel, 15 parts of earthworm castings, 8 parts of desulfurized gypsum, 3 parts of microbial agent, 5 parts of nano humic acid, 18 parts of nano diatomaceous earth and 5 parts of soil conditioner by weight.

[0109] In this embodiment, the crop straw is a mixture of corn straw, rape straw, rice straw, peanut straw, wheat straw, soybean straw and sorghum straw.

[0110] In this embodiment, the microbial agent components include 15 parts of Bacillus subtilis powder, 15 parts of Bacillus subtilis powder, 10 parts of Bacillus licheniformis powder, 8 parts of silicate bacteria powder, 8 parts of salt-tolerant Brazilian Azospirillum powder, 7 parts of Lactobacillus rhamnosus powder, and 4 parts of Enterococcus faecalis powder in parts by weight.

[0111] In this embodiment, the bacterial count of each bacterial powder in the microbial inoculant is 2.0×10 8 cfu / g.

[0112] In this embodiment, the soil conditioner is composed of 40% bamboo biochar, 40% selenium-rich carbonaceous shale powder, 15% wood vinegar, 3% halophilic Exothiorhodospirillum, and 2% acidobacterium.

[0113] In this embodiment, a method for preparing a slow-release microbial fertilizer for improving saline-alkali land comprises the following steps:

[0114] A. First, the crop straw is added into a grinder and crushed, and then sieved to obtain straw powder;

[0115] B. Add earthworm castings, desulfurized gypsum, biochemical fulvic acid, nano humic acid and nano diatomaceous earth to the straw powder, mix thoroughly, add to a stirring tank and stir in sections to obtain a mixture A;

[0116] C. Inoculating the microbial agent into the solid fermentation medium, culturing at a certain temperature for a period of time, and obtaining the solid fermentation medium agent;

[0117] D. Then, mixture A, chitosan / gelatin composite hydrogel, soil conditioner and solid fermentation medium bacterial agent were added to a mixing tank in sequence, fully stirred and mixed at room temperature, and sealed and stored for 4 days to obtain a semi-finished microbial fertilizer;

[0118] E. Finally, add the semi-finished microbial product into the granulator to make a slow-release microbial fertilizer.

[0119] In this embodiment, the rotation speed of the pulverizer in step A is 3000 rpm, the pulverizing time is 65 min, and the fineness of the straw powder after pulverization is 300 mesh.

[0120] In this embodiment, in step B, low-speed stirring is first adopted, and the stirring rate is 300 rpm. After stirring for 10 minutes, high-speed stirring is then adopted, and the stirring rate is 6500 rpm. The stirring time is 40 minutes.

[0121] In this embodiment, the culture temperature in step C is 34° C. and the culture time is 3 days.

[0122] Experimental example:

[0123] The bacterial fertilizers prepared in various embodiments of the present invention and conventional bacterial fertilizers were used to improve the soil, and then the soil properties were tested, and the data obtained were as follows:

[0124] Soil pH Organic matter content increase (%) Conventional fertilizer 8.52 2.2 Embodiment 1 7.32 19.5 Embodiment 2 7.39 20.5 Embodiment 3 7.28 19.8 Embodiment 4 7.29 21.2 Embodiment 5 7.31 20.4 Embodiment 6 7.18 21.9

[0125] The microbial agent added by the present invention contains a large amount of ammonia-fixing bacteria, potassium-dissolving bacteria, and antibiotics, which can effectively supplement the nutrients required for crops at various growth stages, inhibit the growth of various pathogens and pests remaining in the soil, promote the circulation of nutrients such as carbon, nitrogen, phosphorus, and sulfur, and enrich the diversity of dominant bacterial flora in the soil; the soil conditioner added by the present invention can better regulate the physical and chemical properties of the soil, regulate the pH of the soil, prevent the soil from becoming compacted, and effectively avoid the re-accumulation of salt through the synergistic effect of bamboo biomass charcoal, selenium-rich carbonaceous shale powder and bacterial colonies.

[0126] In summary, the preparation method of the present invention is simple, and the prepared slow-release microbial fertilizer has the effects of promoting crop growth, improving saline-alkali soil quality and increasing the organic matter content of the land, and can better regulate the physical and chemical properties of the soil. At the same time, it can also inhibit harmful bacteria, enrich the diversity of beneficial bacteria, and quickly improve the soil structure; the preparation method adopted by the present invention can promote the full mixing of various materials, and in addition, the microbial agent is inoculated into the solid fermentation medium to prepare the solid fermentation medium agent, which can play a role in gathering nutrients and beneficial microorganisms, thereby making the soil fertile and conducive to plant growth.

[0127] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A slow-release microbial fertilizer for improving saline-alkali land, characterized in that: The microbial fertilizer components include 100-150 parts of urea, 40-50 parts of crop straw, 3-9 parts of biochemical fulvic acid, 8-20 parts of chitosan / gelatin composite hydrogel, 10-20 parts of earthworm castings, 4-12 parts of desulfurized gypsum, 1-4 parts of microbial agent, 2-8 parts of nano humic acid, 12-22 parts of nano diatomaceous earth and 2-8 parts of soil conditioner by weight.

2. The slow-release microbial fertilizer for improving saline-alkali land according to claim 1, characterized in that: The microbial fertilizer components include 125 parts of urea, 45 parts of crop straw, 6 parts of biochemical fulvic acid, 14 parts of chitosan / gelatin composite hydrogel, 15 parts of earthworm castings, 8 parts of desulfurized gypsum, 3 parts of microbial agent, 5 parts of nano humic acid, 18 parts of nano diatomaceous earth and 5 parts of soil conditioner by weight.

3. The slow-release microbial fertilizer for improving saline-alkali land according to claim 1, characterized in that: The crop straw is a mixture of corn straw, rape straw, rice straw, peanut straw, wheat straw, soybean straw and sorghum straw.

4. The slow-release microbial fertilizer for improving saline-alkali land according to claim 1, characterized in that: The microbial inoculant components include 10-20 parts of Bacillus subtilis powder, 10-20 parts of Bacillus subtilis powder, 5-15 parts of Bacillus licheniformis powder, 4-12 parts of silicate bacteria powder, 4-12 parts of salt-tolerant Brazilian Azospirillum powder, 4-10 parts of Rhamnosus lactobacillus powder, and 2-6 parts of faecal enterococcus powder by weight.

5. The slow-release microbial fertilizer for improving saline-alkali land according to claim 4, characterized in that: The bacterial count of each bacterial powder in the microbial agent is 1.5×10 8 cfu / g-2.5×10 8 cfu / g.

6. The slow-release microbial fertilizer for improving saline-alkali land according to claim 1, characterized in that: The soil conditioner consists of 40% bamboo biochar, 40% selenium-rich carbonaceous shale powder, 15% wood vinegar, 3% halophilic Exothio-Rhodospirillum and 2% acidobacterium.

7. A method for preparing a slow-release microbial fertilizer for improving saline-alkali land according to claim 1, characterized in that: The preparation method comprises the following steps: A. First, the crop straw is added into a grinder and crushed, and then sieved to obtain straw powder; B. Add earthworm castings, desulfurized gypsum, biochemical fulvic acid, nano humic acid and nano diatomaceous earth to the straw powder, mix thoroughly, add to a stirring tank and stir in sections to obtain a mixture A; C. Inoculating the microbial agent into the solid fermentation medium, culturing at a certain temperature for a period of time, and obtaining the solid fermentation medium agent; D. Then, in a mixing tank, mixture A, chitosan / gelatin composite hydrogel, soil conditioner and solid fermentation medium bacterial agent are added in sequence, fully stirred and mixed at room temperature, and sealed and stored for 3-5 days to obtain a semi-finished microbial fertilizer; E. Finally, add the semi-finished microbial product into the granulator to make a slow-release microbial fertilizer.

8. The method for preparing a slow-release microbial fertilizer for improving saline-alkali land according to claim 7, characterized in that: In the step A, the rotation speed of the pulverizer is 2000-4000 rpm, the pulverizing time is 50-70 min, and the fineness of the pulverized straw powder is 200-400 meshes.

9. The method for preparing a slow-release microbial fertilizer for improving saline-alkali land according to claim 7, characterized in that: In the step B, low-speed stirring is first adopted, the stirring rate is 200-400 rpm, and after stirring for 10 minutes, high-speed stirring is adopted, the stirring rate is 5000-8000 rpm, and the stirring time is 30 minutes to 50 minutes.

10. The method for preparing a slow-release microbial fertilizer for improving saline-alkali land according to claim 7, characterized in that: In step C, the culture temperature is 32° C.-35° C., and the culture time is 2-3 days.