A method for constructing an enhanced soil acid buffer system

Abstract

The application discloses a method for constructing an enhanced soil acid buffer system, and relates to the technical field of acid soil improvement. The application comprises sandy soil / soil treatment and clay treatment. The sandy soil / soil treatment comprises acid soil supplement, acid-base buffer, nitrogen control and acid reduction, and planting of acid-tolerant crops. The clay treatment comprises acid soil reconstruction, acid soil supplement, acid soil buffer, nitrogen control and acid reduction, and planting of acid-tolerant crops. The method can reduce further acidification of soil in the medium and low pH stages and prevent the potential risk of soil acidification from being aggravated through overall construction in multiple aspects.

Description

Technical Field

[0001] This invention relates to the field of acidic soil improvement technology, specifically, to a method for constructing an enhanced soil acid buffering system. Background Technology

[0002] Soil acidification is manifested through soil pH, and the rise and fall of soil pH is directly related to the soil's acid buffering system. The high pH (pH>5.5, calcium carbonate buffering system) and low pH (pH<4.5, aluminum buffering system) stages are classified as secondary soil buffering systems. In this stage, the soil's resistance to exogenous H+ entry is mainly manifested by mineral weathering, exhibiting a relatively large buffering capacity but a slow dynamic, resulting in a slow pH decrease and a strong buffering capacity against exogenous acids, with a small unit decrease in pH value. In the intermediate pH stage (silicate buffering system), the rate of pH decrease is related not only to the rate of cation release from silicate dissolution but also to the content of exchangeable bases in the soil; the lower the content of exchangeable base ions in the soil, the weaker the acid buffering capacity.

[0003] To address the above issues, current technologies generally reduce lime usage and control active calcium at high pH levels, while adding lime to raise the pH and reduce active aluminum at medium and low pH levels. These approaches focus on enhancing acid-base buffering and cannot prevent the exacerbation of the potential risks of soil acidification. Summary of the Invention

[0004] The purpose of this invention is to provide a method for constructing an enhanced soil acid buffering system, which, through comprehensive construction from multiple aspects, reduces further acidification of soil in the medium and low pH stages and prevents the potential risk of soil acidification from escalating.

[0005] To achieve the above objectives, the present invention employs the following technical means:

[0006] A method for constructing an enhanced soil acid buffering system includes sand / loam treatment and clay treatment;

[0007] The sand / loam soil treatment includes acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0008] The clay treatment includes acid soil reconstruction, acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0009] Preferably, the acid-base buffer is used to reconstruct the carbonate buffer system, wherein the acid-base buffer is constructed by applying biochar and quicklime to reconstruct the carbonate buffer system.

[0010] Furthermore, the amount of quicklime used is 3000~6000 kg / hm. 2 The amount of biochar used is 25 kg / mu.

[0011] Furthermore, the nitrogen control and acid reduction are used to increase carbon and reduce nitrogen. The nitrogen control and acid reduction are achieved by reducing the application of nitrogen fertilizer and increasing the application of bean straw powder to increase carbon and reduce nitrogen in the soil.

[0012] Furthermore, the acid soil reconstruction is used to supplement silica and suppress acid, and the acid soil reconstruction adopts the application of quartz sand to supplement silica and suppress acid in the soil.

[0013] Furthermore, the amount of quartz sand used is 0.5 to 2 tons per acre.

[0014] Furthermore, the acid soil supplementation is used to replenish medium-level elements, and the acid soil supplementation is achieved by applying magnesium sulfate and ammonium molybdate.

[0015] Furthermore, the amount of magnesium sulfate used is 5-15 kg / mu, and the amount of ammonium molybdate used is 100-200 g / mu.

[0016] Furthermore, the acid-suitable crop to be planted is corn or soybean, wherein the corn is Xingdan 105 and the soybean is Yunhuanzi 6.

[0017] Furthermore, the amount of corn used is 1-5 kg / mu, and the amount of soybeans used is 5-10 kg / mu.

[0018] The present invention has the following beneficial effects during use:

[0019] The entire system is constructed by considering four aspects: nitrogen control and acid reduction, acid-base buffering, acid soil replenishment, and acid soil reconstruction. It can mitigate further acidification of soils in the medium and low pH stages, prevent the potential risk of soil acidification from escalating, and the resulting soil acidification remediation products are of great significance and have broad market application prospects. Sandy soil, loam, and clay soils are constructed separately. For all three, acid soil remediation can be achieved through planting acid-suitable crops, acid soil replenishment, acid-base buffering, and nitrogen control and acid reduction. For clay soils, a method for acid soil reconstruction and regulation by supplementing silica and suppressing acidity is also added. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the construction of the sand / loam acid buffer system of the present invention.

[0021] Figure 2 This is a schematic diagram illustrating the construction of the clay acid buffer system of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments 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 some embodiments of the present invention, and not all embodiments.

[0023] Therefore, the following detailed description of embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other.

[0025] This invention relates to a method for constructing an enhanced soil acid buffering system, including sand / loam treatment and clay treatment;

[0026] Treatment of sandy / loam soils includes acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops;

[0027] Clay treatment includes acid soil reconstruction, acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0028] Acid-base buffering is used to reconstruct the carbonate buffer system. This is achieved by applying biochar and quicklime to the carbonate buffer system, with the amount of quicklime used being 3000–6000 kg / hm². 2 .

[0029] Thus, by reconstructing the carbonate buffering system, the problem of weak and highly variable soil pH buffering capacity can be addressed. The application of slaked lime and biochar is crucial. Slaked lime primarily increases exogenous calcium in the soil; the concentration of exchangeable calcium increases linearly with the amount of slaked lime applied. Higher slaked lime application results in lower potential acid content and a significant reduction in exchangeable aluminum concentration, thus increasing pH and reducing the harmful effects of aluminum toxicity on crops. Biochar application significantly increases the content of exchangeable basic ions in the soil, improving soil fertility. Biochar application significantly enhances organic matter, available potassium (K), available phosphorus (P), and total nitrogen (N) in red soil, while also increasing crop yield.

[0030] And through 3000~6000 kg / hm 2 The addition of quicklime and 25 kg / mu of biochar allows the combined application of quicklime and biochar to significantly increase the pH of red soil and reduce the content of exchangeable acids in red soil. The overall acid-reducing effect is between that of applying biochar alone and applying lime alone.

[0031] Meanwhile, the pH value in red soil increases significantly after the application of quicklime alone, thus affecting the availability of phosphorus and other trace elements. Consequently, the application of quicklime alone reduces the nitrogen content of plants. This application, however, combines a specific amount of biochar with lime to alleviate the problem of nitrogen reduction in plants caused by the application of quicklime alone.

[0032] The aforementioned acidification of soil is achieved by applying magnesium sulfate and ammonium molybdate. For ammonium molybdate, molybdenum is a micronutrient essential for plant growth. Appropriate amounts of molybdenum not only improve plant growth and yield but also promote phosphorus absorption, enhance plant resistance, and improve soil microbial diversity. However, excessive molybdenum is significantly toxic to plants, inhibiting root growth and development. The toxicity threshold of molybdenum in soil is closely related to the soil environment. Generally, as the amount of molybdate added increases, the amount of molybdate in the soil increases, thus approaching the toxicity threshold of molybdenum. Therefore, excessive molybdate can lead to slow plant growth or even death. Thus, the dosage of molybdate is highly limited; it needs to be applied in small amounts multiple times to ensure the long-term promoting effect of molybdate on plant growth.

[0033] The application of quicklime reduces free iron ions in the soil, and the application of ammonium molybdate reduces free iron ions in the soil.

[0034] After molybdate ions react with free iron ions to form compounds, the amount of free molybdate ions in the soil increases compared to soils without added slaked lime, causing the molybdate concentration to exceed the soil threshold. To avoid the negative impact of excessive molybdate ions on plant growth, the amount of molybdate used needs to be reduced. However, this not only affects the effectiveness of acidification in replenishing soil acidity but also significantly shortens the time during which molybdenum promotes plant growth. Therefore, ammonium molybdate needs to be applied in small amounts and multiple times to maintain the concentration of molybdate ions in the soil.

[0035] Therefore, in the system of this application that combines molybdate with quicklime and magnesium sulfate, it is important to improve the effect of molybdate while avoiding the concentration of molybdate in the soil from exceeding the toxicity threshold, so as to enhance the effect of soil acidification.

[0036] In this application, when adjusting sandy soils and loams with large sand and silt particle sizes, legume straw powder is introduced during the subsequent nitrogen control and acid reduction process. Utilizing the good air and water permeability of sandy and loam soils, the introduced legume straw powder degrades at a certain rate in these soils. This degradation reduces the amount of free molybdate ions in the soil after the combined use of quicklime and ammonium molybdate, temporarily fixing a large number of free molybdate ions. This keeps the concentration of molybdate ions in the soil below its toxicity threshold even when there is an excess of molybdate ions. Therefore, while using legume straw powder for nitrogen control and acid reduction, the degradation of legume straw powder in sandy or loam soils can also increase the application rate of ammonium molybdate. With the increased application rate of ammonium molybdate, over time, the amount of molybdenum in the soil and the degradation products of legume straw powder gradually decrease, and the previously temporarily fixed free molybdate ions become free again in the soil environment, maintaining the molybdate concentration in the soil. This effectively increases the content of available molybdenum in the soil and improves the effect of supplementing acid soil. After applying ammonium molybdate, the applied molybdate is released slowly, resulting in a more significant and longer-lasting growth-promoting effect on plants.

[0037] The aforementioned nitrogen control and acid reduction are used to increase carbon and reduce nitrogen. The nitrogen control and acid reduction are achieved by reducing the application of nitrogen fertilizer and increasing the application of bean straw powder, thereby increasing carbon and reducing nitrogen in the soil.

[0038] After the application of legume straw powder, during soil nitrogen transformation, both the nitrification of ammonium nitrogen in the soil and the uptake of ammonium nitrogen by plants produce H2O. + Excessive nitrogen fertilizer application, leading to unabsorbed or leached nitrate nitrogen by plants, is a key mechanism in nitrogen-induced soil acidification. Applying more legume straw powder can effectively alleviate soil pH decline, while simultaneously increasing soil fertility and crop yield. Legume straw powder not only increases soil carbon sources and improves soil fertility, but also slowly releases nitrogen, reducing nitrogen leaching and potential soil acidity caused by nitrogen fertilizer application. Furthermore, its low C / N ratio facilitates decomposition, and its high nitrogen content makes it a suitable supplement after nitrogen fertilizer reduction.

[0039] The aforementioned acid soil reconstruction is used to supplement silica and suppress acid. Acid soil reconstruction involves applying quartz sand to supplement silica and suppress acid in the soil.

[0040] When using quartz sand for acid soil reconstruction, the aluminosilicate minerals in the soil decompose to produce oxide minerals with the highest weathering degree. Large amounts of silica and basic ions are leached away, and the clay minerals are mainly 1:1 type kaolinite, while iron and aluminum oxides accumulate in large quantities. The silica ions (Si) in the quartz sand... 4+Silica ions interact and adsorb onto the surface of soil particles. They can also form adsorption complexes with aluminum hydroxide, iron oxides, and clay minerals on the surface of soil particles. This adsorption process, through mechanisms such as electrostatic interaction, surface coordination, and chemical reactions, can improve soil cation exchange capacity and increase fertilizer retention. Adding silica sand can reduce the leaching of large amounts of silica and basic ions, thereby inhibiting pH decrease. Silica increases soil pH, promotes the precipitation of heavy metal ions and the formation of silicate complexes, and reduces the concentration and mobility of active heavy metal ions in the soil. Simultaneously, the soluble silicates produced by silica sand in the soil hydrolyze in aqueous solution to form gel-like H4SiO4, which can adsorb toxic metal ions and other harmful substances, mitigating toxicity. For silica sand to achieve its intended effect, it must be used before crop planting.

[0041] Furthermore, in clay environments, due to the differences between clay and sandy / loam environments, the degradation rate and mode of legume straw powder differ from those in sandy / loam environments due to the poor permeability of clay, making it impossible to achieve the desired increase in molybdate application. Therefore, combining silica supplementation and acid suppression in clay not only provides a long-lasting silica supplementation and acid suppression effect, but also modifies the properties of clay by increasing its permeability, making its physicochemical properties closer to those of sandy / loam. Thus, by applying quartz sand, legume straw powder in clay environments can achieve a similar degradation process as in sandy / loam environments, allowing it to still achieve a slow release effect on molybdate. Moreover, in clay environments with abundant minerals, high water content, and poor permeability, quartz sand can fully react with environmental microorganisms and other components, resulting in a more prominent and stable effect in silica supplementation and acid suppression. Example

[0042] A method for constructing an enhanced soil acid buffering system includes sand / loam treatment and clay treatment;

[0043] The sand / loam soil treatment includes acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0044] The clay treatment includes acid soil reconstruction, acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0045] The acid-base buffer is used to reconstruct the carbonate buffer system, and the acid-base buffer is constructed by applying biochar and quicklime to reconstruct the carbonate buffer system.

[0046] Furthermore, the amount of quicklime used is 3000~6000 kg / hm². 2 The amount of biochar used is 25 kg / mu.

[0047] Furthermore, the nitrogen control and acid reduction are used to increase carbon and reduce nitrogen. The nitrogen control and acid reduction are achieved by reducing the application of nitrogen fertilizer and increasing the application of bean straw powder to increase carbon and reduce nitrogen in the soil.

[0048] Furthermore, the acid soil reconstruction is used to supplement silica and suppress acid, and the acid soil reconstruction adopts the application of quartz sand to supplement silica and suppress acid in the soil.

[0049] Furthermore, the amount of quartz sand used is 0.5 tons per acre.

[0050] Furthermore, the acid soil supplementation is used to replenish medium-level elements, and the acid soil supplementation is achieved by applying magnesium sulfate and ammonium molybdate.

[0051] Specifically, the amount of magnesium sulfate used is 5 kg / mu, and the amount of ammonium molybdate used is 100 g / mu.

[0052] Furthermore, the acid-suitable crop to be planted is corn or soybean, wherein the corn is Xingdan 105 and the soybean is Yunhuanzi 6.

[0053] Furthermore, the amount of corn used is 1 kg / mu, and the amount of soybeans used is 5 kg / mu. Example

[0054] A method for constructing an enhanced soil acid buffering system includes sand / loam treatment and clay treatment;

[0055] The sand / loam soil treatment includes acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0056] The clay treatment includes acid soil reconstruction, acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0057] The acid-base buffer is used to reconstruct the carbonate buffer system, and the acid-base buffer is constructed by applying biochar and quicklime to reconstruct the carbonate buffer system.

[0058] Furthermore, the amount of quicklime used is 3000~6000 kg / hm². 2 The amount of biochar used is 25 kg / mu.

[0059] Furthermore, the nitrogen control and acid reduction are used to increase carbon and reduce nitrogen. The nitrogen control and acid reduction are achieved by reducing the application of nitrogen fertilizer and increasing the application of bean straw powder to increase carbon and reduce nitrogen in the soil.

[0060] Furthermore, the acid soil reconstruction is used to supplement silica and suppress acid, and the acid soil reconstruction adopts the application of quartz sand to supplement silica and suppress acid in the soil.

[0061] Furthermore, the amount of quartz sand used is 2 tons per acre.

[0062] Furthermore, the acid soil supplementation is used to replenish medium-level elements, and the acid soil supplementation is achieved by applying magnesium sulfate and ammonium molybdate.

[0063] Specifically, the amount of magnesium sulfate used is 15 kg / mu, and the amount of ammonium molybdate used is 200 g / mu.

[0064] Furthermore, the acid-suitable crop to be planted is corn or soybean, wherein the corn is Xingdan 105 and the soybean is Yunhuanzi 6.

[0065] Furthermore, the amount of corn used is 5 kg / mu, and the amount of soybeans used is 10 kg / mu. Example

[0066] A method for constructing an enhanced soil acid buffering system includes sand / loam treatment and clay treatment;

[0067] The sand / loam soil treatment includes acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0068] The clay treatment includes acid soil reconstruction, acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops.

[0069] The acid-base buffer is used to reconstruct the carbonate buffer system, and the acid-base buffer is constructed by applying biochar and quicklime to reconstruct the carbonate buffer system.

[0070] Furthermore, the amount of quicklime used is 3000~6000 kg / hm². 2 The amount of biochar used is 25 kg / mu.

[0071] Furthermore, the nitrogen control and acid reduction are used to increase carbon and reduce nitrogen. The nitrogen control and acid reduction are achieved by reducing the application of nitrogen fertilizer and increasing the application of bean straw powder to increase carbon and reduce nitrogen in the soil.

[0072] Furthermore, the acid soil reconstruction is used to supplement silica and suppress acid, and the acid soil reconstruction adopts the application of quartz sand to supplement silica and suppress acid in the soil.

[0073] Furthermore, the amount of quartz sand used is 1 ton per acre.

[0074] Furthermore, the acid soil supplementation is used to replenish medium-level elements, and the acid soil supplementation is achieved by applying magnesium sulfate and ammonium molybdate.

[0075] Specifically, the amount of magnesium sulfate used is 10 kg / mu, and the amount of ammonium molybdate used is 150 g / mu.

[0076] Furthermore, the acid-suitable crop to be planted is corn or soybean, wherein the corn is Xingdan 105 and the soybean is Yunhuanzi 6.

[0077] Furthermore, the amount of corn used is 2 kg / mu, and the amount of soybeans used is 6 kg / mu.

[0078] Compared with Example 3, the amount of biochar used in this comparative example is less than 25 kg / acre.

[0079] Compared with Example 3, the biochar dosage in this comparative example is greater than 25 kg / acre.

[0080] Compared to Example 3, the quartz sand in this comparative example was applied after crop planting.

[0081] Compared to Example 1, in this comparative example, quicklime was applied alone, and the applied biochar was removed.

[0082] Compared with Example 1, in this comparative example, the soybean straw powder was replaced with grain straw powder.

[0083] Compared with Example 1, the amount of ammonium molybdate used in this comparative example was adjusted to 20~70g / mu.

[0084] Compared with Example 1, in this comparative example, the quartz sand was replaced with ordinary commercially available silicon fertilizer.

[0085] Comparing Comparative Examples 1 and 2 with Example 3, it can be observed that the nitrogen supplementation effect of biochar changes with variations in the amount of biochar used. When the amount of biochar is low, it is difficult to achieve the desired nitrogen supplementation effect on the plants, resulting in nitrogen deficiency in both the above-ground and below-ground parts of the plants. Excessive application of biochar, on the other hand, can excessively increase soil pH, leading to a deficiency of micronutrients such as phosphorus, which further affects the nitrogen content in both the above-ground and below-ground parts of the plants, and may even reduce it. Therefore, the addition of a specific amount of biochar not only regulates soil fertility but also enhances the effectiveness of biochar.

[0086] Compared with Example 3, when quartz sand was added after crop planting, the soil properties changed due to the crop planting, making it difficult for quartz sand to produce soluble silicates. Therefore, it could not generate colloidal H4SiO4, and the effect of quartz sand in this system was greatly reduced.

[0087] Comparing Comparative Example 4 with Example 1, after applying quicklime alone, the potassium content in both the aboveground and underground parts of the plants in Comparative Example 4 and Example 1 was almost the same. However, compared with Example 1, the nitrogen content in both the aboveground and underground parts of Comparative Example 4 decreased. Therefore, in Example 1, by applying a certain amount of biochar, the combined use of quicklime and biochar not only retained the effect of quicklime in increasing the potassium content of the plants, but also avoided the decrease in nitrogen content caused by applying quicklime alone.

[0088] Compared to Example 1, Comparative Example 5 soybeans exhibited yellowing leaves due to excessive molybdenum absorption, and the lengths of both roots and above-ground parts were reduced compared to Example 1. Furthermore, the protein and vitamin C content of the soybeans grown in Comparative Example 5 was significantly lower. In contrast, the above-ground and underground parts of the soybeans grown in Example 1 were longer than the average growth rate of commercially available soybeans, indicating that even with the application of large amounts of ammonium molybdate, Example 1 did not negatively impact soybean growth and even had a beneficial effect on it.

[0089] Comparing Comparative Example 6 with Example 1, the soybeans grown in Comparative Example 6 showed little difference in growth rate during the first crop compared to Example 1. However, after the first crop was harvested, the growth rate of the soybeans in Comparative Example 6 during the second crop was significantly lower than that in Example 1. Furthermore, the protein and vitamin C content of the soybeans in the second crop was lower than that of the soybeans in Example 1. Combining the aforementioned comparison results between Comparative Example 5 and Example 1, the application of a large amount of ammonium molybdate in this application not only increases the molybdate toxicity threshold in the soil but also allows for the slow release of molybdate, ensuring that the available molybdenum in the soil remains at a high and harmless level. This not only promotes crop growth but also effectively prolongs the promotion period, resulting in more lasting soil fertility.

[0090] Compared with Example 1, Comparative Example 7 showed that after replacing the quartz sand with silicon fertilizer, the soybean plants grown in Comparative Example 7 exhibited symptoms of excessive molybdenum intake because the silicon fertilizer could not improve the physical and chemical properties of the clay. Under the application of a large amount of ammonium molybdate, the soybean straw powder could not play a role in molybdate ion absorption. This not only affected the normal growth of soybeans, but also had a significant impact on the nutritional content of soybeans in this application.

[0091] From a general perspective of remediation theory, acidified soils (sandy, loam, and clay) share some commonalities and characteristics. These commonalities can be addressed through the cultivation of acid-suitable soil varieties, supplementation of acid-deficient soils, acid-base buffering, and nitrogen control to reduce acidity. Furthermore, for clay soils, a method of acid reconstruction and regulation by supplementing silicon and suppressing acidity has been added. Theoretically, the common characteristics of acidified soils are: under conditions of intense soil weathering and rainfall, the levels of silicon and basic ions (Ca) in the soil... 2+ Mg 2+ K + Na + Significant leaching or runoff occurs, leading to the accumulation of iron and aluminum oxides in the soil, reduced base saturation and acid buffering capacity, and decreased H2O. + Replacing cation exchange sites on the soil surface, soil H + Increased saturation leads to the production of large amounts of exchangeable acids, resulting in soil acidification. Soil H₂ + Further disruption of the silicate mineral crystal structure leads to the release of aluminum, which then undergoes further hydrolysis, releasing even more H₂.+ This exacerbates soil acidification. The chemical processes of soil acidification are mainly controlled by the loss of basic ions and H+. + Factors such as increased aluminum ion activation.

[0092] Clay characteristics: Its properties are exactly the opposite of sandy soil. It is heavy and sticky, with poor tilth. The lack of large pores between soil particles results in poor aeration and water permeability; it is neither drought-tolerant nor waterlogging-tolerant, but it has strong water and fertilizer retention capacity. Soil temperature rises slowly, making it difficult for plant roots to grow downwards. Adding silica and suppressing acidity will change the soil structure of clay, increasing porosity; silica addition can repair soil aggregate structure and reduce soil clumping.

[0093] Therefore, this application considers the construction of the entire system from four aspects: nitrogen control and acid reduction, acid-base buffering, acid soil replenishment, and acid soil reconstruction. It can mitigate further acidification of soils in the medium and low pH stages, prevent the potential risk of soil acidification from escalating, and the resulting soil acidification remediation products also have significant importance and broad market application prospects. Sandy soil, loam, and clay are constructed separately. For all three, acid soil remediation can be achieved through planting acid-suitable crops, acid soil replenishment, acid-base buffering, and nitrogen control and acid reduction. Furthermore, a method for acid soil reconstruction and regulation by supplementing silica and suppressing acidity is added specifically for clay.

[0094] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for constructing an enhanced soil acid buffering system, characterized in that, This includes treatment of sandy / loam soils and clay soils; The sand / loam treatment includes acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops. The clay treatment includes, in sequence, acid soil reconstruction, acid soil filling, acid-base buffering, nitrogen control and acid reduction, and planting acid-suitable crops. The acid-base buffer is used to reconstruct the carbonate buffer system. This acid-base buffering is achieved by applying biochar and slaked lime to reconstruct the carbonate buffer system. The amount of slaked lime used is 3000-6000 kg / hm². 2 The amount of biochar used is 25 kg / mu; The nitrogen control and acid reduction are used to increase carbon and reduce nitrogen. The nitrogen control and acid reduction are achieved by reducing the application of nitrogen fertilizer and increasing the application of bean straw powder to increase carbon and reduce nitrogen in the soil. The acid soil reconstruction is used to supplement silica and suppress acid. The acid soil reconstruction adopts the application of quartz sand to supplement silica and suppress acid in the soil. The amount of quartz sand used is 0.5~2 tons / acre. The acid soil supplementation is used to supplement medium-level elements. The acid soil supplementation is achieved by applying magnesium sulfate and ammonium molybdate. The amount of magnesium sulfate used is 5-15 kg / mu, and the amount of ammonium molybdate used is 100-200 g / mu.

2. The method for constructing an enhanced soil acid buffering system according to claim 1, characterized in that, The acid-tolerant crops to be planted are corn or soybeans, with the corn being Xingdan 105 and the soybeans being Yunhuanzi 6.

3. The method for constructing an enhanced soil acid buffering system according to claim 2, characterized in that, The amount of corn used is 1-5 kg / mu, and the amount of soybean used is 5-10 kg / mu.

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