Application of soil amendment in improving saline soil of coastal plain to plant foxtail millet

Abstract

The invention discloses an application of a soil conditioner in improving saline soil of a coastal plain and planting foxtail millet. The soil conditioner is prepared by the following method: ploughing land, mixing eupolyphaga excrement and straw, piling the mixture on the ploughed land for fermentation, and obtaining the soil conditioner after fermentation is finished, according to the improvement method, the soil is ploughed again, so that the soil conditioner is uniformly mixed with the soil. The mass ratio of the eupolyphaga excrement to the straw is 1: 1; the straw is wheat straw. The total application amount of the eupolyphaga excrement and the straw is 50-200kg / mu. According to the method, the eupolyphaga excrement and the straw are jointly fermented, the fermentation product is used as the soil conditioner to improve the saline soil of the coastal plain and plant the millet, the yield of the millet planted in the saline soil of the coastal plain can be increased, and the pH and the total salt content of the saline soil of the coastal plain can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of saline-alkali land improvement, and in particular to application of a soil conditioner in improving saline soil in coastal plains for planting millet. Background Art

[0002] The essence of saline-alkali soil formation is the redistribution of soluble salts in the soil, and the accumulation of salt in the soil surface exceeds the normal value. Mildly salinized soil has a soil salt content of 0.1%~0.2%; moderately salinized soil has a soil salt content of 0.2%~0.4%; and severely salinized soil has a soil salt content of 0.4%~0.6%. In addition, according to the cause, saline-alkali land is divided into: naturally formed saline-alkali land in coastal areas: the salt content is mainly sodium chloride, mainly distributed in coastal areas; saline-alkali land formed by groundwater inland areas: the salt content is mainly sodium sulfate; soda saline-alkali land: the salt content is mainly sodium carbonate and sodium bicarbonate; artificially caused saline-alkali land secondary salinization saline-alkali land: excessive application of chemical fertilizers causes soil compaction and decreased fertility, etc.

[0003] At present, there are several main methods for improving saline-alkali land: 1. Irrigation and salt washing, by repeatedly flushing and removing salt from the soil, thereby reducing the salt content of the soil; 2. Planting salt-alkali tolerant crops; 3. Increasing the application of organic matter. Organic fertilizer can increase the organic matter in the soil, promote soil looseness and air permeability, and adjust the pH of the soil. Crushed or decomposed straw can be combined with deep plowing to improve the looseness and air permeability of the soil. Among them, increasing the application of organic matter is mainly used to adjust the pH of the soil and increase soil nutrients. However, for saline-alkali land, in addition to reducing the pH, it is also necessary to reduce the salt content so that crops can be planted in saline-alkali soil. Increasing the application of organic matter is feasible for planting rice in saline-alkali land. Rice is more salt-tolerant than other food crops, and the salt in the soil will be continuously diluted and discharged through long-term flooding and frequent drainage and water changes. Although millet has a certain degree of salt-alkali tolerance, it can only grow at a low salt concentration of %. When the salt concentration reaches 1-2%, the growth of millet will be restricted, and when the salt concentration is above 2%, the growth of millet will be significantly restricted. "The Effect of Different Fertilization Modes on Saline-Alkali Soil Improvement and Millet Growth" (Han Fei et al., Soil Bulletin, August 2020, Vol. 51, No. 4) mentioned that the organic fertilizer replacement treatment significantly increased the grain yield compared with the conventional fertilization treatment, and the total salt content of the soil layer decreased and the pH value decreased. However, its improvement on saline-alkali soil is very limited, with the total salt content reduced by 4.74% compared with CK, and the pH only reduced by 2.32%. Therefore, further improvement is needed for the saline soil in the coastal plain. Summary of the invention

[0004] In view of the above-mentioned prior art, the purpose of the present invention is to provide an application of a soil conditioner in improving the saline soil of the coastal plain for planting millet. The present invention utilizes earthworm feces and straw for co-fermentation, and uses the fermentation product as a soil conditioner to improve the saline soil of the coastal plain and plant millet, which can increase the yield of millet planted in the saline soil of the coastal plain and reduce the pH and total salt content of the saline soil of the coastal plain.

[0005] To achieve the above object, the present invention adopts the following technical solution: The present invention provides an application of a soil conditioner in improving the saline soil of a coastal plain for planting millet. The soil conditioner is prepared by the following method: Plowing the land, mixing earthworm excrement with straw, piling it on the plowed land for fermentation, and obtaining a soil conditioner after the fermentation is completed; The improvement is to plow the land again to evenly mix the soil conditioner with the soil.

[0006] Preferably, the tillage depth is 0-20 cm; the re-tillage depth is 0-20 cm.

[0007] Preferably, the mass ratio of the earthworm feces to the straw is 1:1; and the straw is wheat straw.

[0008] Preferably, the straw is crushed to a length of no more than 1 cm.

[0009] Preferably, the fermentation is to mix the earthworms with the straw respectively, adjust the moisture content to 50-70wt%, and evenly spread them on the plowed land for natural fermentation.

[0010] Preferably, the fermentation time is 7 to 15 days, and the pile is turned every two days.

[0011] Preferably, the total salt content of the coastal plain saline soil is 0.1-0.3%.

[0012] Preferably, the total amount of earthworm feces and straw applied is 50-200 kg / mu.

[0013] Preferably, the improvement is to increase the yield of millet and reduce the pH and total salt content of saline soil in the coastal plain.

[0014] Preferably, the millet row spacing is 40 cm; the millet sowing rate is 1.0 kg / mu.

[0015] Beneficial effects of the present invention: (1) The present invention prepares a soil conditioner by mixing earthworm feces and straw on cultivated land and fermenting them. The soil conditioner is then plowed into the soil, which not only reduces the pH and total salt content of the saline soil in the coastal plain, but also increases the millet yield, which is 22% higher than the millet yield grown on the saline soil in the coastal plain.

[0016] (2) The improver of the present invention is easy to prepare. It only requires spreading earthworm feces and straw on the saline soil of the coastal plain for natural fermentation. The improvement of pH and total salt content of the saline soil of the coastal plain is significantly higher than that of using finished organic fertilizer. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 : Photos of ears, stems and roots of each treatment group. DETAILED DESCRIPTION

[0018] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0019] As introduced in the background technology section, although millet has a certain degree of salt and alkali resistance, it can only grow under low salt concentrations. When the salt concentration reaches 1-2%, the growth of millet will be restricted, and when the salt concentration is above 2%, the growth of millet will be significantly limited.

[0020] Based on this, the purpose of the present invention is to provide an application of a soil conditioner in improving the planting of millet in the saline soil of the coastal plain. When studying the intercropping of millet and soybean (see the patent with application number CN2024114887809, a method for intercropping millet and soybean in strips), the present invention uses earthworm feces and soybean straw for fermentation to increase the intercropping yield of soybean and millet, reduce weed growth, and reduce crop diseases and insect pests. During this research process, it was unexpectedly discovered that fermentation with earthworm feces and soybean straw can be used as an improver to improve the pH and total salt content of saline soil in the coastal plain. Therefore, on this basis, further research found that mixing earthworm feces and wheat straw in a mass ratio of 1:1 has a better effect. The microorganisms produced by the fermentation of earthworm feces and wheat straw can improve the soil structure, increase organic matter, and promote salt degradation after entering the soil. Wheat straw also has the effect of improving saline-alkali soil, so the present invention improves the saline soil of the coastal plain through multiple effects.

[0021] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments.

[0022] The test materials used in the examples of the present invention are all conventional test materials in the art and can be purchased through commercial channels.

[0023] Example Mix 100kg of earthworm manure and 100kg of wheat straw (<1cm) evenly, then spray water to make the moisture content 70%. Sprinkle the total weight of earthworm manure and wheat straw evenly on the land to be cultivated at 200kg / mu, cover and ferment for 10 days, turn over every two days to obtain soil conditioner. Sprinkle evenly on the land to be cultivated and turn over 20cm.

[0024] Comparative Example 1 The difference from the embodiment is that wheat straw is not added, and the soil conditioner is finally obtained. The land is plowed again to make the soil conditioner and the soil evenly mixed, and the plowing depth is 20 cm.

[0025] Comparative Example 2 The difference from the embodiment is that no earthworm feces are added, and the soil conditioner is finally obtained. The land is plowed again to make the soil conditioner and the soil evenly mixed, and the plowing depth is 20 cm.

[0026] Comparative Example 3 The commercially available sheep manure organic fertilizer (purchased from Shijiazhuang Wofuwo Fertilizer Co., Ltd.) was used as a soil conditioner, and 200 kg / mu was evenly spread on the land to be cultivated and plowed to 20 cm. The commercially available sheep manure organic fertilizer is a fermented fertilizer and is used directly as a conditioner.

[0027] Comparative Example 4 The difference from the embodiment is that an equal amount of commercially available sheep manure organic fertilizer (purchased from Shijiazhuang Wofuwo Fertilizer Co., Ltd.) is used to replace earthworm feces, and finally a soil conditioner is obtained. The land is plowed again to evenly mix the soil conditioner with the soil, and the plowing depth is 20 cm.

[0028] Test example: Potted plant test In November 2023, a potted plant experiment was conducted. The millet variety used was Jigu 42. The potted soil was modified by adding NaCl and NaCO 3The saline soil was simulated to make the total salt content of the soil 0.3%, the pH 7.70, and the organic matter content 6.0 g / kg. The soil density was determined by the ring knife method, and the amount of the modifier added was calculated. The experiment was divided into 6 groups: a blank control group (CK) without adding soil modifier; an embodiment group: 0.4 g / kg of the modifier prepared in the embodiment was added to the potted soil; a comparative example group 1: 0.2 g / kg of the modifier prepared in comparative example 1 was added to the potted soil; a comparative example group 2: 0.2 g / kg of the modifier prepared in comparative example 2 was added to the potted soil; a comparative example group 3: 0.4 g / kg of the modifier prepared in comparative example 3 was added to the potted soil; a comparative example group 4: 0.4 g / kg of the modifier prepared in comparative example 4 was added to the potted soil. There were 20 pots in each group, and 1 plant was planted in each pot. The same daily management was carried out on each group, and no additional pesticides or fertilizers were used during daily management. During the maturity period of millet, 5 pots of millet with the same growth were randomly selected from each group. The plant height, stem diameter and leaf area were measured with a steel ruler and the average values ​​were calculated. After the millet matured, it was harvested and threshed, and the average grain weight per plant was calculated. The results are shown in Table 1. The ears, stems and roots of millet were photographed. Figure 1 After millet harvest, the pH, total salt content and organic matter content of the soil in each pot were tested; and the change rates of pH, total salt and organic matter in the soil before the addition of the amendment and after millet harvest were calculated. The average values ​​of the results are shown in Table 2.

[0029] The soil samples were collected from the potted plants, air-dried and sieved, and the water-soil ratio was 2.5:1 and the CO 2 The pH of the soil was determined by water extraction-pH meter method; the content of soil organic matter was determined by potassium dichromate volumetric method-external heating method; the water-soil ratio was 5:1 and the CO 2 The water extraction-drying residue weight method was used to determine the soluble salt content in soil.

[0030] Table 1 According to Table 1 and Figure 1 It can be seen that the plant height, stem thickness and leaf area of ​​the embodiment group are significantly increased compared with the CK group and the comparative examples 1 to 3, and the grain weight of a single plant is also significantly higher than that of the CK group. Since millet does not tiller under saline-alkali conditions, one plant produces one ear, and the grain weight of each plant is the total amount of grains per ear; it can be seen that the millet root system of the embodiment group is well developed, the root length is longer than that of the CK and comparative examples 1 to 4, the stem is the thickest, and the ears are fuller. The plant height, stem thickness, leaf area and yield of the embodiment group are also higher than those of the comparative example 4 group, indicating that the soil improvement using earthworm feces and wheat straw fermentation in the present invention is better than finished organic fertilizer + straw.

[0031] Table 2 According to Table 2, it can be seen that the pH and total salt content of the embodiment group are significantly lower than those of the CK group, and the organic matter content is significantly increased. It can be seen that the organic matter content of the CK group decreased before and after the addition of the modifier, while the organic matter content of the embodiment group increased. Although the decrease in organic matter is related to the planting of millet, some of the modifiers of the embodiment group and comparative examples 1, 3, and 4 contain fermented organic fertilizers. The microorganisms produced by fermentation can improve the soil structure, increase organic matter, and promote salt degradation; but due to potted planting restrictions, the increase in soil organic matter content is limited. Compared with comparative examples 1 to 4, the pH and total salt content of the embodiment group decreased more, and the organic matter content increased more.

[0032] Test Example 2: Field Test On June 18, 2024, millet was planted in Beishangzhuang Village, Nandagang Industrial Park, Huanghua City, and the millet variety was Jigu 42. The properties of the soil in the area are: the total salt content of 0-20 cm soil is 0.285%, the pH is 7.74, and the organic matter content is 5.61 g / kg; the total salt content of 20-40 cm soil is 0.288%, the pH is 7.81, and the organic matter content is 5.51 g / kg. The row spacing of millet is 40 cm, and the millet sowing rate is 1.0 kg / mu. The experiment was divided into 6 groups: a blank control group (CK) without adding soil conditioner, an embodiment group, and comparative examples 1 to 4 groups, and the test area of ​​each group was 10m×10m. The same daily management was carried out on each group, and no additional pesticides or fertilizers were used during daily management. Before adding the modifier, 10 points in each group were selected to take soil samples to detect the pH, total salt content and organic matter content of the soil. After millet was harvested, soil samples were taken at the same location to test the pH, total salt content and organic matter content of the soil. The dry weight of millet produced in each group was weighed and the yield was calculated. The results are shown in Table 3.

[0033] pH change rate = (soil pH before amendment addition - soil pH after millet harvest) / soil pH before amendment addition × 100%; Total salt change rate = (total salt content of soil before adding amendments - total salt content of soil after millet harvest) / total salt content of soil before adding amendments × 100%; Organic matter change rate = (organic matter content of soil after millet harvest - organic matter content of soil before adding amendment) / organic matter content of soil before adding amendment × 100%.

[0034] Soil samples with a depth of 0-20 cm and 20-40 cm were collected, air-dried and sieved, and the water-soil ratio was 2.5:1. 2 The pH of the soil was determined by water extraction-pH meter method; the content of soil organic matter was determined by potassium dichromate volumetric method-external heating method; the water-soil ratio was 5:1 and the CO 2 The water extraction-drying residue weight method was used to determine the soluble salt content in soil.

[0035] Table 3 Table 4 It can be seen from Tables 3 and 4 that the yield of the Example group was increased by about 22% compared with the CK group. The pH and total salt content of the Example group were significantly lower than those of the CK group, and the organic matter content was significantly increased.

[0036] The change rates of total salt content and organic matter content in each group in the pot test of Test Example 1 were not as much increased as those in the field test of Test Example 2, and the pH drop rate was much higher than that of Test Example 2. However, it can be seen in general that the present invention can significantly increase the yield of millet planted in saline-alkali land, reduce H and total salt content, and increase organic matter content by fermenting earthworm feces and straw.

[0037] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. Application of a soil conditioner in improving the saline soil of coastal plains for planting millet, characterized in that: The soil conditioner is prepared by the following method: Plowing the land, mixing earthworm excrement with straw, piling it on the plowed land for fermentation, and obtaining a soil conditioner after the fermentation is completed; The improvement method is to plow the land again to evenly mix the soil conditioner with the soil.

2. The use according to claim 1, characterized in that: The depth of the tillage is 0-20 cm; the depth of the second tillage is 0-20 cm.

3. The use according to claim 1, characterized in that: The mass ratio of earthworm excrement to straw is 1:1; and the straw is wheat straw.

4. The use according to claim 3, characterized in that: The straw is crushed to a length no greater than 1 cm.

5. The use according to claim 1, characterized in that: The fermentation comprises mixing earthworms with straws respectively, adjusting the moisture content to 50-70wt%, and evenly spreading the mixture on the plowed land for natural fermentation.

6. The use according to claim 5, characterized in that: The fermentation time is 7 to 15 days, and the pile is turned every two days.

7. The use according to claim 1, characterized in that: The total salt content of the saline soil in the coastal plain is 0.1-0.3%.

8. The use according to claim 1, characterized in that: The total amount of earthworm excrement and straw applied is 50-200 kg / mu.

9. The use according to claim 1, characterized in that: The improvement is to increase the yield of millet and reduce the pH and total salt content of the saline soil in the coastal plain.

10. The use according to claim 1, characterized in that: The row spacing of the millet is 40 cm; the sowing amount of the millet is 1.0 kg / mu.

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