Method for retarding soil acidification and increasing content of fixed inorganic carbon in soil

Abstract

The invention provides a method for retarding soil acidification and increasing the content of fixed inorganic carbon in soil, and relates to the technical field of soil improvement. According to the method, the wollastonite is firstly crushed, then the crushed wollastonite is uniformly spread on the surface of the soil and then mixed into a soil plough layer, and the improvement of retarding soil acidification and increasing soil fixed inorganic carbon is realized. The crushed wollastonite is spread on the surface of the soil and then mixed into a plough layer to generate stable bicarbonate which is beneficial to sealing of inorganic carbon in the soil, acidic substances in the soil can be remarkably neutralized, the soil acidification process is relieved, the air permeability and the water binding capacity of the soil are improved, and then the fertility of the soil is improved; crop root growth is promoted, nutrient absorption of plants is improved, crop yield and quality are further improved, and the method is an efficient and low-cost acidified soil improvement technology.

Description

Technical Field

[0001] The invention relates to the technical field of soil improvement, and in particular to a method for slowing down soil acidification and increasing the content of fixed inorganic carbon in the soil. Background Art

[0002] Soil acidification refers to the process in which the concentration of hydrogen ions (pH value) in the soil increases, resulting in a decrease in soil pH value. In agricultural production, due to the long-term use of chemical fertilizers (especially nitrogen fertilizers) and the influence of certain agricultural production methods and acid rain, acidic substances (such as sulfates, nitrates, etc.) in the soil continue to accumulate, leading to soil acidification. This phenomenon not only affects the root growth of crops, but also reduces the absorption of mineral nutrients by crops, leading to a decrease in soil fertility.

[0003] At present, many traditional soil improvement methods mainly rely on alkaline substances such as lime and gypsum to neutralize acidic substances. Although they are effective quickly, they are often unable to effectively maintain the stable pH of the soil for a long time, which can easily cause soil compaction and high transportation costs. At the same time, there are problems such as high resource consumption, high costs, and a greater impact on other components of the soil. In addition, in the context of "dual carbon", agricultural production also needs to consider the carbon emissions of agricultural improvement measures.

[0004] The invention patent with the publication number CN119193426A discloses a Brevibacillus brevis ZLP-152, with the deposit number CGMCC No.32228. The strain can continuously produce alkali throughout the growth cycle and can antagonize various pathogens such as cotton red rot bacteria. The composite bacterial agent formed by the strain, phosphate-solubilizing bacteria HM0332 and silicate bacteria HM8841 can improve soil acidification and / or improve the soil microecological environment. However, this method involves the preservation and cultivation of strains, which is costly, and the strains have certain adaptability and cannot fully adapt to all types of acidified soils.

[0005] The invention patent with publication number CN118879338A provides a soil conditioner for soil acidification control and its preparation and application. The preparation method of the soil conditioner is as follows: S1, prepare AEB nanocomposite material, specifically as follows: first prepare modified nano carbon black: specifically, modify nano carbon black to obtain carboxyl modified nano carbon black; then prepare nano lignin solution: mix nano lignin, ethanol and water, and stir well to obtain; finally, add attapulgite and the prepared modified nano carbon black to the prepared nano lignin solution, stir well and ultrasonically treat, and then dry and grind to obtain AEB nanocomposite material; S2, mix AEB nanocomposite material with dolomite powder in proportion to obtain. The soil conditioner prepared by the present invention has a fast onset and a high soil pH buffering capacity. It can fundamentally and comprehensively treat acidified soil, and is not prone to re-acidification and soil compaction. The yield-increasing effect is more significant when combined with the application of organic fertilizer. This method involves the preparation and modification of nanomaterials, which are complex and costly, thus increasing the modification cost of acidified soil.

[0006] In addition, in the context of global warming and climate change, the problem of carbon emissions is becoming increasingly serious. Soil is considered to be one of the important sources and sinks of global carbon storage, capable of absorbing and fixing a large amount of carbon dioxide. Especially in agricultural ecosystems, reasonable carbon sequestration technology and soil improvement methods can not only alleviate soil acidification, but also play a role in carbon fixation, help reduce the concentration of carbon dioxide in the atmosphere, and improve the ecological environment. Summary of the invention

[0007] In view of this, the present invention provides a method for slowing down soil acidification and increasing the content of soil fixed inorganic carbon. The present invention effectively slows down soil acidification and increases the content of soil fixed inorganic carbon by optimizing the wollastonite crushing and application method. It plays an important role in improving soil quality, increasing agricultural productivity and carbon fixation, has good application prospects and economic benefits, and has a positive impact on the environment.

[0008] The method for slowing down soil acidification and increasing the fixed inorganic carbon content of soil provided by the present invention comprises the following steps:

[0009] First, wollastonite is crushed, and then the crushed wollastonite is evenly spread on the soil surface and mixed into the soil tillage layer.

[0010] Preferably, the particle size of the wollastonite after crushing is less than 1 mm.

[0011] Preferably, the amount of pulverized wollastonite added is 10-100 t / hm 2 .

[0012] Preferably, the crushed wollastonite is mixed into the soil tillage layer by deep plowing or spreading with fertilizing equipment.

[0013] Preferably, the depth of the soil tillage layer is 0 to 30 cm.

[0014] Preferably, the crushed wollastonite can be used in combination with other fertilizers or soil conditioners.

[0015] Compared with the prior art, the beneficial technical effects of the present invention are:

[0016] In the present invention, the crushed wollastonite is spread on the soil surface and then mixed into the tillage layer. The wollastonite will react with the H + Reacting or weathering rapidly with organic acids secreted by plants and microorganisms, in addition to consuming H + In addition, it also releases basic cations (Ca, Mg), which fix gaseous CO2 and convert it into HCO3 or CO3. It can not only alleviate soil acidification in the short and long term, but also enhance the carbon fixation capacity of the ecosystem.

[0017] The present invention adjusts the particle size of wollastonite (less than 1 mm) and the addition amount (10 to 100 t / hm 2 ) is strictly limited, ensuring its uniform distribution in the soil, increasing the contact area between wollastonite and the soil, improving the reaction efficiency, and avoiding the problem of soil alkalinization. It plays the best role in improving soil carbon sequestration, slowing down acidification, and improving soil fertility.

[0018] The method of the invention adopts deep plowing or fertilizing equipment to evenly spread wollastonite, and the treatment depth is 0-30 cm, which can ensure the soil improvement effect and has relatively low treatment cost, and is suitable for wide promotion.

[0019] The wollastonite of the present invention can be used in combination with other fertilizers or soil conditioners to further enhance the effects of slowing down soil acidification, promoting soil inorganic carbon fixation, etc. This combination of multiple effects not only improves the overall fertility of the soil, but also helps to increase the growth and yield of crops. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] Figure 1 The pH (left) and bicarbonate content (right) of the soil in the experimental group and the control group after 80 days;

[0022] Among them: * indicates that there is a significant difference in T test (P<0.05). DETAILED DESCRIPTION

[0023] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. 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.

[0024] The method for slowing down soil acidification and increasing the fixed inorganic carbon content of soil provided by the present invention comprises the following steps:

[0025] S1, crushing wollastonite;

[0026] S2. Spread the crushed wollastonite in S1 evenly on the soil surface and mix it into the soil tillage layer.

[0027] The first step of the present invention is to crush the wollastonite. In some specific embodiments of the present invention, the particle size of the wollastonite after crushing is less than 1 mm. The present invention does not strictly limit the crushing method of wollastonite, and conventional crushing methods such as ball milling, air flow crushing, impact milling, roller crushing, ultrasonic crushing, jaw crushing, roller grinding, wet grinding, mechanical ball milling, etc. can all be used for the crushing process of the wollastonite of the present invention. The selection of a specific crushing method depends on the specific needs of different acidified soil improvements, including factors such as the required particle size, crushing efficiency, equipment cost and energy consumption. However, the present invention strictly limits the particle size of the wollastonite after crushing, and the specific reasons are as follows: First, the smaller the particle size of the wollastonite, the larger the surface area of ​​the wollastonite, thereby increasing its contact area with the soil, which helps to increase the reaction rate of the wollastonite with the acidic substances in the soil, and the soluble substances in the wollastonite particles with a small particle size can dissolve more quickly and react with water and acidic substances in the soil, thereby effectively neutralizing the acidic substances, thereby slowing down the rate of soil acidification. In contrast, large-particle wollastonite has a small surface area and slow reaction, and cannot quickly and effectively change the acid-base balance of the soil. In addition, after crushing and limiting the particle size of the product, it is possible to ensure that the particle size distribution of wollastonite is more uniform, which is convenient for its distribution in the soil to avoid the situation where the local concentration is too high or too low, and to avoid the formation of obvious particle agglomeration of wollastonite in the soil, affecting the application effect. Finally, small-particle wollastonite helps to form finer silicate minerals and inorganic compounds such as calcium and magnesium, which help to promote carbon fixation and acidification mitigation in the soil, while large-particle wollastonite cannot achieve this effect. In general, the present invention improves its contact efficiency with the soil, increases the reaction rate, and ensures the uniform distribution of wollastonite by limiting the particle size of wollastonite to maximize its effect of slowing down soil acidification and promoting carbon fixation, avoids its adverse effects on soil structure, and ensures the sustainability of the improved soil.

[0028] The second step of the present invention is to evenly spread wollastonite on the soil surface and then mix it into the soil tillage layer. In some specific embodiments of the present invention, the amount of wollastonite added after crushing is 10-100t / hm 2 , which is determined according to the acidification of the soil, that is, the pH value of the soil.

[0029] The main function of wollastonite in the present invention is to neutralize acidic substances in the soil, especially to alleviate soil acidification through the reaction of its carbonate components (such as calcium carbonate) with acidic substances (such as hydrogen ions). Therefore, the amount of addition needs to be adjusted according to the degree of soil acidification. By reacting with acidic substances in the soil, the stable bicarbonate formed by wollastonite can promote soil carbon sequestration. Wollastonite can also promote the fixation of inorganic carbon in the soil, thereby improving the carbon storage capacity of the soil. In addition to alleviating acidification, wollastonite also plays a role in improving soil structure, increasing soil permeability and water retention, and improving soil fertility. However, it is necessary to maintain an appropriate amount of addition to improve the physical and chemical properties of the soil and promote the growth of crop roots and the absorption of nutrients. Too little dosage will not significantly improve soil fertility, and too much dosage will lead to excessive calcium and magnesium content in the soil, affecting the absorption of other nutrients (such as potassium and phosphorus) by crops, thereby affecting crop growth. The present invention has shown through long-term field monitoring and experimental results that adding 10 to 100 t / hm 2 Wollastonite can play the best role in improving soil fertility, slowing down acidification, and increasing carbon storage.

[0030] Therefore, the present invention ensures that soil acidification is effectively alleviated by limiting the amount of wollastonite added after crushing, without causing soil alkalinization problems; improves the fixation capacity of soil inorganic carbon and maximizes the carbon fixation effect; ensures the improvement of soil fertility and promotes the healthy growth of crops; controls economic costs and avoids waste of resources.

[0031] In some specific embodiments of the present invention, the crushed wollastonite is mixed into the soil tillage layer by deep plowing or fertilizing equipment, and the depth of the soil tillage layer is 0 to 30 cm. The present invention maximizes the improvement effect of the soil and crop growth environment by limiting the depth of action of the crushed wollastonite in the soil. This depth range is the main distribution area of ​​the roots of most crops, so wollastonite can effectively improve the nutrient absorption capacity of crops within this depth range. Wollastonite reacts with acidic substances in the soil within this depth range to slow down soil acidification, which has a direct impact on crop growth and nutrient absorption. In terms of economy and operability, the treatment depth of 0 to 30 cm has high economy and operability, and exceeding this depth will lead to an increase in treatment costs. In addition, when used in places such as grasslands, in view of the provisions of relevant laws and regulations, wollastonite cannot be mixed into the soil by means of plowing, so it can be evenly spread on the soil surface.

[0032] In some preferred embodiments of the present invention, the crushed wollastonite can be used in combination with other fertilizers or soil conditioners to further enhance the effect of slowing down soil acidification and increasing the fixation of inorganic carbon in the soil, thereby enhancing soil fertility and crop yield.

[0033] The present invention forms stable bicarbonate in the soil by adding crushed wollastonite, thereby improving the inorganic carbon capacity of the soil. Long-term field monitoring and experimental results show that the addition of wollastonite can significantly increase the carbon storage capacity of the soil and play an important role in carbon fixation in agricultural ecosystems.

[0034] In order to further illustrate the present invention, the following examples are used to provide a detailed description. The raw materials used in the following examples of the present invention are all commercially available, wherein the element composition of wollastonite is calculated by mass percentage, as follows:

[0035] Ca 50.2114%, O 34.627%, Si 9.841%, Mg 4.8474%, Fe 0.149%, Ba0.1228%, Al 0.0597%, Mn 0.0332%, Sr 0.0326%, K 0.0259%, Cl 0.0205%, Zn 0.0113%, P 0.0102%, S 0.008%.

[0036] Unless otherwise specified, all experiments were repeated 3 times and the results were expressed as mean values.

[0037] Example 1

[0038] The Hulunbuir grassland was selected for the experiment of using wollastonite to slow down soil acidification and increase soil fixed inorganic carbon. The steps are as follows:

[0039] S1. crush wollastonite to a particle size of less than 1 mm;

[0040] S2, crushed wollastonite at 10t / hm 2 Spread the dosage evenly on the soil surface.

[0041] The untreated soil was used as the control group (CK) and the treated soil was used as the experimental group (Wol). After 80 days, the soil was sampled to measure the pH and inorganic carbon content of the soil. The results are as follows: Figure 1 shown.

[0042] Depend on Figure 1 It can be seen that the method of the present invention can be used to treat acidified soil, which can increase the soil pH by about 0.5 units and increase the inorganic carbon content of the soil, which is equivalent to increasing the grassland inorganic carbon pool by about 0.068t CO2 / hm 2 .

[0043] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for slowing down soil acidification and increasing the content of soil fixed inorganic carbon, characterized in that: The following steps are involved: First, wollastonite is crushed, and then the crushed wollastonite is evenly spread on the soil surface and mixed into the soil tillage layer.

2. A method for slowing down soil acidification and increasing soil fixed inorganic carbon content according to claim 1, characterized in that: It is characterized in that The particle size of the wollastonite after crushing is less than 1 mm.

3. A method for slowing down soil acidification and increasing soil fixed inorganic carbon content according to claim 1, characterized in that: The amount of wollastonite added after crushing is 10-100t / hm 2 .

4. A method for slowing down soil acidification and increasing soil fixed inorganic carbon content according to claim 1, characterized in that: The crushed wollastonite is mixed into the soil tillage layer by deep plowing or spreading with fertilizing equipment.

5. A method for slowing down soil acidification and increasing soil fixed inorganic carbon content according to claim 1, characterized in that: It is characterized in that The depth of the soil tillage layer is 0 to 30 cm.

6. A method for slowing down soil acidification and increasing soil fixed inorganic carbon content according to claim 1, characterized in that: It is characterized in that The crushed wollastonite can be used in combination with other fertilizers or soil conditioners.

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