Organic soil conditioner capable of reducing cadmium and increasing selenium and application of organic soil conditioner

Abstract

The invention belongs to the technical field of organic soil conditioners, and particularly relates to a cadmium-reducing selenium-increasing organic soil conditioner and application thereof. The organic soil conditioner is prepared from the following raw materials in parts by weight: 20-60 parts of chicken manure organic fertilizer; 3-9 parts of a mixed bacterial liquid; 5 to 15 parts of humic acid; 1.8 to 2.2 parts of a surfactant; 9-12 parts of a microbial nutrient solution; the mixed bacterial liquid is prepared by mixing a bacterial liquid of stenotrophomonas maltophilia ATCC 17666 and a bacterial liquid of bacillus mycoides ATCC 10206 in equal volume. Effect inspection on the soil conditioner provided by the invention through multiple action ways shows that the soil conditioner provided by the invention is high in stability and has good cadmium-reducing and selenium-enriching effects. The materials are natural, and the risk of secondary pollution to the soil environment is small.

Description

Technical Field

[0001] The invention belongs to the technical field of organic soil conditioners, and in particular relates to an organic soil conditioner capable of reducing cadmium and increasing selenium, and application thereof. Background Art

[0002] Selenium (Se) is an essential trace element for the human body. It plays an important role in many biological processes of the human body, including anti-oxidative stress, immune response, etc. At the same time, Se is also recognized by the medical community as one of the anti-cancer elements. The most important way for the human body to absorb Se is through diet, and the natural way is also the safest way for the human body to supplement Se. The content of Se in agricultural products mainly comes from the cultivated soil where they are planted, and is closely related to the soil parent material.

[0003] Se-rich farmland often faces the problem of excessive heavy metals, among which cadmium (Cd) is the main element. Cd is a harmful heavy metal with strong mobility. It is very easy to accumulate in the human body through the food chain, causing harm to the human body. Therefore, how to reduce the effectiveness of Cd in the soil and increase the effectiveness of Se in the soil is the key to the safe use of natural selenium-rich farmland contaminated by Cd. Currently, commonly used soil conditioners only passivate heavy metals in the soil, and they also have a passivating effect on Se. Therefore, the research and development of soil conditioners that reduce Cd and increase Se is of great significance.

[0004] The existing heavy metal soil conditioners only reduce the effectiveness of heavy metals, but do not improve the effectiveness of Se, or even reduce it. Microbial soil conditioners only act on soils contaminated by heavy metals, and have poor effects on soils with high selenium and high cadmium. Compared with traditional inorganic soil passivators, organic biological conditioners are more environmentally friendly and can reduce the risk of secondary pollution caused by adding conditioners. However, there is currently a lack of organic microbial conditioners on the market that can both reduce cadmium and increase selenium. Summary of the invention

[0005] In order to make up for the lack of soil conditioners in reducing cadmium and selenium in cadmium-contaminated farmland in natural selenium-rich areas, the present invention aims to develop an organic soil conditioner suitable for cadmium-contaminated farmland in natural selenium-rich areas.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] The present invention first provides an organic soil conditioner, which is made of the following raw materials by weight:

[0008] 20-60 parts of chicken manure organic fertilizer;

[0009] Mix 3 to 9 parts of bacterial solution;

[0010] Humic acid 5-15 parts;

[0011] 1.8-2.2 parts of surfactant;

[0012] 9-12 parts of microbial nutrient solution;

[0013] The mixed bacterial liquid is prepared by mixing equal volumes of the bacterial liquid of Oligotrophomonas maltophilia ATCC 17666 and the bacterial liquid of Bacillus mycoides ATCC 10206.

[0014] The strains selected in the present invention have strong tolerance to Cd, and can still grow when the amount of Cd added to the solid culture medium reaches 300 mg / kg. When the amount of Cd added to the liquid culture medium is 100 mg / kg, the growth curve still does not show a significant change. In the soil culture experiment, the content of effective Cd elements in the soil decreased significantly, and the effective Se elements increased significantly when the mixed bacterial liquid was added. The Cd content of Chinese cabbage decreased significantly, and the Se content increased significantly, showing a synergistic effect.

[0015] Preferably, the effective viable counts in both bacterial solutions are 2×10 8 ~4×10 8 cfu / g.

[0016] Preferably, the surfactant is rhamnolipid.

[0017] Preferably, the microbial nutrient solution is a beef extract peptone liquid culture medium, which is prepared from 2.95-3.05 g beef extract, 9-11 g peptone, 4-6 g NaCl, and 1000 ml water, and has a pH of 7.4-7.6.

[0018] The present invention further provides a method for preparing the organic soil conditioner, comprising the following steps:

[0019] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into liquid culture medium, cultured and mixed to prepare a mixed bacterial solution;

[0020] 2) Crush the chicken manure organic fertilizer;

[0021] 3) crushing and mixing the humic acid, the mixed bacterial liquid, and the crushed chicken manure organic fertilizer, and then watering and stirring to obtain a mixed material;

[0022] 4) Add surfactant and microbial nutrient solution to the mixed material, stir evenly, and let it stand for 1 to 2 days.

[0023] The present invention again provides the use of the organic soil conditioner in improving soil, wherein the improvement includes reducing cadmium and enriching selenium.

[0024] Preferably, the method for using the organic soil conditioner comprises the following steps: applying the organic soil conditioner to the soil two weeks before crop planting, and then tilling and mixing the soil.

[0025] More preferably, the application amount of the organic soil conditioner is 4%-6% of the mass of the improved soil.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The present invention selects organic additives of humic acid and chicken manure organic fertilizer combination, while increasing soil organic matter content, providing nutrients for strains, and taking into account organic matter decomposition time. Humic acid decomposes faster after entering the soil, and can provide nutrients for soil microorganisms faster. The process of its decomposition into small molecular acids can release electrons, and the oxidizing ability it produces can enhance the effectiveness of soil Se. Chicken manure organic fertilizer decomposes slower, and can provide nutrients for microorganisms and planted crops in a long-term manner. At the same time, the more stable organic aggregates it generates are also easier to adsorb soil effective state Cd.

[0028] 2. The soil conditioner of the present invention has high stability and good cadmium reduction and selenium enrichment effects. It is made from natural materials and has little risk of secondary pollution to the soil environment. DETAILED DESCRIPTION

[0029] The present invention is described in detail below in conjunction with specific examples, but it should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the following examples are conventional means well known to those skilled in the art, and the materials, reagents, etc. used in the following examples, unless otherwise specified, can be obtained from commercial sources.

[0030] The chicken manure organic fertilizer in the following examples was purchased from Shenyang Beinong Biotechnology Co., Ltd. Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 in the following examples were purchased commercially, and the bacterial liquid was obtained by expanding the culture using conventional methods.

[0031] Example 1

[0032] An organic soil conditioner, the raw materials of which are: 20g chicken manure organic fertilizer; 3g mixed bacterial solution; 5g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the effective viable bacteria count in both bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0033] The preparation method of the above organic soil conditioner has the following steps:

[0034] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0035] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0036] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0037] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0038] Example 2

[0039] An organic soil conditioner, the raw materials of which are: 20g chicken manure organic fertilizer; 6g mixed bacterial solution; 10g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the effective viable bacteria count in both bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0040] The preparation method of the above organic soil conditioner has the following steps:

[0041] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0042] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0043] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0044] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0045] Example 3

[0046] An organic soil conditioner, the raw materials of which are: 20g chicken manure organic fertilizer; 9g mixed bacterial solution; 15g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the effective viable bacteria count in both bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0047] The preparation method of the above soil conditioner comprises the following steps:

[0048] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0049] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0050] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0051] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0052] Example 4

[0053] An organic soil conditioner, the raw materials of which are: 40g chicken manure organic fertilizer; 3g mixed bacterial solution; 10g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the effective viable bacteria count in both bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0054] The preparation method of the above organic soil conditioner has the following steps:

[0055] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0056] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0057] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0058] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0059] Example 5

[0060] An organic soil conditioner, the raw materials of which are: 40g chicken manure organic fertilizer; 6g mixed bacterial solution; 15g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the effective viable bacteria count in both bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0061] The preparation method of the above organic soil conditioner has the following steps:

[0062] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0063] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0064] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0065] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0066] Example 6

[0067] An organic soil conditioner, the raw materials of which are: 40g chicken manure organic fertilizer; 9g mixed bacterial solution; 5g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the number of effective live bacteria in the two bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0068] The preparation method of the above soil conditioner comprises the following steps:

[0069] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0070] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0071] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0072] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0073] Example 7

[0074] An organic soil conditioner, the raw materials of which are: 60g chicken manure organic fertilizer; 3g mixed bacterial solution; 15g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the effective viable bacteria count in both bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0075] The preparation method of the above organic soil conditioner has the following steps:

[0076] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0077] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0078] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0079] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0080] Example 8

[0081] An organic soil conditioner, the raw materials of which are: 60g chicken manure organic fertilizer; 6g mixed bacterial solution; 5g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the effective viable bacteria count in both bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0082] The preparation method of the above soil conditioner comprises the following steps:

[0083] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0084] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0085] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0086] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0087] Example 9

[0088] An organic soil conditioner, the raw materials of which are: 60g chicken manure organic fertilizer; 9g mixed bacterial solution; 10g humic acid; 2g surfactant; 10g microbial nutrient solution. The mixed bacterial solution is prepared by mixing equal volumes of Oligotrophomonas maltophilia ATCC 17666 bacterial solution and Bacillus mycoides ATCC 10206 bacterial solution, and the number of effective live bacteria in the two bacterial solutions is 4×10 8 cfu / g. The surfactant is rhamnolipid, and the microbial nutrient solution is beef extract peptone liquid culture medium, which consists of: 3.0g beef extract, 10.0g peptone, 5.0g NaCl, 1000ml water, pH: 7.4-7.6.

[0089] The preparation method of the above organic soil conditioner has the following steps:

[0090] 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into beef extract peptone liquid medium and cultured in a constant temperature incubator at 37°C for 24 h. The effective viable count was diluted to 4×10 8 cfu / g, and then mixed in a 1:1 ratio to prepare a mixed bacterial solution.

[0091] 2) Crush the chicken manure organic fertilizer into 200 mesh powder.

[0092] 3) Mix humic acid, bacterial liquid and crushed chicken manure organic fertilizer, add water and stir for 2 hours.

[0093] 4) Add rhamnolipid and microbial nutrient solution to the above materials, mix and stir for 2 hours, and then let stand for 24 hours.

[0094] Soil conditioner performance evaluation:

[0095] In order to better evaluate the performance of the soil conditioner used in the present invention and further verify the synergistic effect between the functional components, with reference to Examples 1 to 9, a soil improvement effect comparison test was conducted by adjusting the ratio of the soil conditioner.

[0096] Test Example 1

[0097] The potted test was conducted in the experimental greenhouse in Yangling District, Xianyang City, Shaanxi Province from April 2024 to June 2024. The soil used was from Hengkou Town, Hanbin District, Ankang City, Shaanxi Province. The pH of the test soil sample was 6.26, the organic matter content was 31.92g / kg, the cadmium content was 1.24mg / kg, and the selenium content was 0.762mg / kg. 10 treatment groups were set up, and the soil conditioners of Examples 1 to 9 were applied in turn. A blank control group (CK) was set up. The soil conditioner formulas of Treatment Groups 1-9 were subjected to a three-factor three-level orthogonal test on chicken manure organic fertilizer, mixed bacterial solution and humic acid. The settings are shown in Table 1:

[0098] Table 1 Preparation of organic soil conditioner

[0099]

[0100]

[0101] Usage: Add the above soil conditioner into the soil at a ratio of 5% of the soil mass and mix well two weeks before planting Chinese cabbage.

[0102] Analysis and determination: The pakchoi was harvested after 45 days of growth, the soil was washed with tap water, dried, and then sterilized at 105°C for 30 minutes, then dried at 70°C to constant weight, and the dry weight of the plant was weighed. Grind it with a stainless steel grinder and store it in a ziplock bag for later use. The potted soil was naturally air-dried and sieved, and stored in a ziplock bag. The removal rate of the soil state-effective Cd content and the reduction rate of the pakchoi Cd content were measured, and the results are shown in Table 2:

[0103] Table 2 Removal rate of soil available Cd content and reduction rate of Cd content in Chinese cabbage

[0104]

[0105] Note: “-” means the data is not included.

[0106] It can be seen from Table 2 that organic soil conditioners with different ratios can effectively reduce the available Cd content in soil and the Cd content in pakchoi, and the most suitable ratio can be obtained based on the range analysis and variance analysis of the orthogonal experiment.

[0107] Table 3 Range analysis of soil available Cd content

[0108]

[0109] Table 4 Variance analysis table of soil available Cd content

[0110] Sources of variance Sum of Squares of Deviations Degrees of Freedom Mean Square F-number P-value Significance Chicken manure organic fertilizer 0.05 2 0.025 56.729 0 ** Bacterial liquid 0.006 2 0.003 7.009 0.005 ** Humic acid 0 2 0 0.464 0.635 error 0.009 20 0

[0111] From the range analysis table of soil available Cd content (Table 3), it can be seen that the addition amount of chicken manure organic fertilizer and mixed bacterial solution has a significant effect on the soil available Cd, and the addition amount of humic acid has no significant effect on the soil available Cd. Therefore, the optimum addition amount of humic acid is C1 according to the minimum addition amount. From the range analysis table (Table 4), it can be seen that the best addition amount of chicken manure organic fertilizer for reducing soil available Cd is A3, and the best mixed bacterial solution is B3.

[0112] Table 5 Analysis of the range of Cd content in Chinese cabbage

[0113]

[0114]

[0115] Table 6 Analysis of variance table of Cd content in pakchoi

[0116]

[0117] From the range analysis table of Cd content in pakchoi (Table 5), it can be seen that the addition amount of chicken manure organic fertilizer and mixed bacterial solution has a significant effect on the Cd content of pakchoi, and the addition amount of humic acid has no significant effect on the effective Cd of pakchoi, so the optimum addition amount of humic acid is C1 according to the minimum addition amount. From the range analysis table (Table 6), it can be seen that the best addition amount of chicken manure organic fertilizer for reducing effective Cd in soil is A3, and the best mixed bacterial solution is B3.

[0118] Overall, A3B3C1 has the best effect on reducing the available Cd content in soil and the Cd content in pakchoi.

[0119] Table 7 Growth rate of available Se content in soil and Se content in pakchoi

[0120]

[0121] Note: “-” means the data is not included.

[0122] It can be seen from Table 7 that different ratios of organic soil conditioners can effectively increase the available Se content in soil and the Se content in pakchoi, and the most suitable ratio can be obtained based on the range analysis and variance analysis of the orthogonal experiment.

[0123] Table 8 Analysis of the range of soil available Se content

[0124]

[0125] Table 9 Variance analysis of soil available Se content

[0126] Sources of variance Sum of Squares of Deviations Degrees of Freedom Mean Square F-number P-value Significance Chicken manure organic fertilizer 1530.572 2 765.286 2.733 0.089 Bacterial liquid 5972.611 2 2986.305 10.666 0.001 * Humic acid 3754.315 2 1877.158 6.705 0.006 * error 5599.432 20 279.972

[0127] From the range analysis table of soil available Se content (Table 8), it can be seen that the addition amount of mixed bacterial solution and humic acid has a significant effect on soil available Se, and the addition amount of chicken manure organic fertilizer has no significant effect on soil available Se. Therefore, the optimum addition amount of chicken manure organic fertilizer is A1 according to the minimum addition amount. From the range analysis table (Table 9), it can be seen that the best addition amount of mixed bacterial solution for increasing soil available Se is B3, and the best humic acid is C2.

[0128] Table 10 Analysis of the range of Se content in pakchoi

[0129]

[0130]

[0131] Table 11 Analysis of variance of Se content in pakchoi

[0132] Sources of variance Sum of Squares of Deviations Degrees of Freedom Mean Square F-number P-value Significance Chicken manure organic fertilizer 873.997 2 436.999 2.99 0.073 Bacterial liquid 2641.721 2 1320.861 9.038 0.002 ** Humic acid 1458.238 2 729.119 4.989 0.017 * error 2922.888 20 146.144

[0133] From the range analysis table of Se content in pakchoi (Table 10), it can be seen that the addition amount of mixed bacterial solution and humic acid has a significant effect on the Se content in pakchoi, and the addition amount of chicken manure organic fertilizer has no significant effect on the Se content in pakchoi. Therefore, the optimum addition amount of chicken manure organic fertilizer is A1 according to the minimum addition amount. From the range analysis table (Table 11), it can be seen that the best addition amount of chicken manure organic fertilizer for increasing Se in pakchoi is B3, and the best addition amount of humic acid is C2.

[0134] Overall, A1B3C2 had the best effect on reducing the available Cd content in soil and the Cd content in pakchoi.

[0135] Considering the combination of Cd and Se, the best effect of reducing Cd and enriching Se in the soil was achieved when chicken manure organic fertilizer, mixed bacterial solution and humic acid were added in an amount of A3B3C2.

[0136] Table 12 Changes in fresh weight and dry weight of Chinese cabbage

[0137]

[0138]

[0139] Note: “-” means the data is not included.

[0140] From the table of changes in fresh weight and dry weight of Chinese cabbage (Table 12), it can be seen that each treatment increased the fresh weight and dry weight of Chinese cabbage, among which the most significant effects were achieved when chicken manure organic fertilizer, mixed bacterial liquid, and humic acid were added in an amount of A3B3C2.

[0141] Table 13 Changes in soil organic matter

[0142] serial number Soil organic matter g / kg Rate of change CK 30.13 - 1 34.12 11.69％ 2 35.23 14.48％ 3 35.79 15.81％ 4 37.41 19.46％ 5 37.59 19.85％ 6 38.19 21.11％ 7 39.03 22.80％ 8 39.92 24.52％ 9 40.01 24.69％

[0143] Note: “-” means the data is not included.

[0144] From the table of soil organic matter changes (Table 13), it can be seen that the most significant improvement effect is achieved when chicken manure organic fertilizer, mixed bacterial solution, and humic acid are added in an amount of A3B3C3.

[0145] Based on the comprehensive effects of various treatments on soil available Cd, available Se, Cd content and Se content of Chinese cabbage, fresh weight and dry weight of Chinese cabbage, and changes in soil organic matter, the addition of chicken manure organic fertilizer, mixed bacterial solution, and humic acid showed the best improvement effect.

[0146] Test Example 2

[0147] In order to better evaluate the effects of adding Oligotrophomonas maltophilia ATCC 17666 (recorded as bacteria A) and Bacillus mycoides ATCC 10206 (recorded as bacteria B) on soil cadmium reduction and selenium enrichment as well as the growth of pakchoi, organic soil conditioners were prepared with reference to the ratios in Table 14, and potted experiments were carried out. The preparation method and use method of the organic soil conditioner were as described above.

[0148] Table 14 Proportions of organic soil conditioners

[0149] deal with Chicken manure organic fertilizer Bacterial liquid Humic acid Rhamnolipid Microbial culture medium No bacteria added 40 0 10 2 10 Add mixed bacterial solution 40 6 10 2 10 Add single bacteria A 40 6 10 2 10 Add single B bacteria 40 6 10 2 10

[0150] Table 15 Measurement results of soil physical and chemical indexes and pakchoi growth indexes It can be seen from Table 15 that Oligotrophomonas maltophilia ATCC 17666 and Bacillus ATCC 10206 have a synergistic effect. After adding the mixed bacteria, compared with the addition of the two strains alone, the effective Cd content in the soil and the Cd content in pakchoi decreased, and the effective Se content in the soil and the Se content in pakchoi increased.

[0151] It should be noted that when the claims of the present invention involve numerical ranges, it should be understood that the two endpoints of each numerical range and any numerical value between the two endpoints can be selected. In order to avoid redundancy, the present invention describes a preferred embodiment.

[0152] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0153] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An organic soil conditioner, characterized in that: Made from the following raw materials by weight: 20-60 parts of chicken manure organic fertilizer; Mix 3 to 9 parts of bacterial solution; Humic acid 5-15 parts; 1.8-2.2 parts of surfactant; 9-12 parts of microbial nutrient solution; The mixed bacterial liquid is prepared by mixing equal volumes of the bacterial liquid of Oligotrophomonas maltophilia ATCC 17666 and the bacterial liquid of Bacillus mycoides ATCC 10206.

2. The organic soil conditioner according to claim 1, characterized in that The effective viable counts in both bacterial solutions were 2×10 8 ~4×10 8 cfu / g.

3. The organic soil conditioner according to claim 1, characterized in that The surfactant is rhamnolipid.

4. The organic soil conditioner according to claim 1, characterized in that The microbial nutrient solution is a beef extract peptone liquid culture medium, which is prepared from 2.95-3.05g beef extract, 9-11g peptone, 4-6g NaCl and 1000ml water, and has a pH of 7.4-7.

6.

5. The method for preparing the organic soil conditioner according to any one of claims 1 to 4, characterized in that: The following steps are involved: 1) Oligotrophomonas maltophilia ATCC 17666 and Bacillus mycoides ATCC 10206 were inoculated into liquid culture medium, cultured and mixed to prepare a mixed bacterial solution; 2) Crush the chicken manure organic fertilizer; 3) crushing and mixing the humic acid, the mixed bacterial liquid, and the crushed chicken manure organic fertilizer, and then watering and stirring to obtain a mixed material; 4) Add surfactant and microbial nutrient solution to the mixed material, stir evenly, and let it stand for 1 to 2 days.

6. Use of the organic soil conditioner according to any one of claims 1 to 4 in improving soil, characterized in that: The improvements include cadmium reduction and selenium enrichment.

7. Use of the organic soil conditioner according to claim 6 in improving soil, characterized in that: The method for using the organic soil conditioner comprises the following steps: applying the organic soil conditioner to the soil two weeks before crop planting, and then tilling and mixing.

8. Use of the organic soil conditioner according to claim 7 in improving soil, characterized in that: The application amount of the soil conditioner is 4%-6% of the mass of the improved soil.

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