Hydrolyzed polysaccharide-biofilm soil protectant for seedling soil and methods of use

Abstract

This invention relates to the field of soil conditioning or soil stabilizing materials, and discloses a hydrolyzed polysaccharide-biofilm soil protectant for initial soil conditioning and its application method. It utilizes a large amount of pectin-based hydrolyzed polysaccharides produced during the degradation of waste fruits and vegetables by microorganisms, including acid-producing bacteria, to rapidly aggregate soil particles, resisting wind and water erosion while allowing fungal hyphae to attach. Organic acids, as a byproduct, enhance mineral weathering and release nutrients from the minerals. Plant stem powder mixed into the soil along with waste fruits and vegetables is decomposed by fungi, and combined with nutrients released from the minerals and nitrogen-fixing bacteria regulating the carbon-nitrogen ratio, it maintains the growth of biofilm-producing bacteria, phosphorus- and potassium-solubilizing bacteria, etc., producing a biofilm to continue maintaining soil particle aggregation and releasing nutrients to maintain fertility, thereby supporting vegetation growth and maintaining organic matter supply and circulation. The combination of these factors achieves the improvement of initial soil conditioning without consuming large amounts of chemical agents and fertilizers.

Description

Technical Field

[0001] This invention relates to the field of soil conditioning materials or soil stabilizing materials, and in particular to a hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation and its application method. Background Technology

[0002] Primary soils refer to soils with a weak degree of development, indistinct soil profile layers, significant parent material characteristics, and a relatively young stage, which are clearly different from zonal soils.

[0003] Initially prepared soil is extremely detrimental to vegetation growth, with the main adverse effects including: 1. Extremely barren, with a severe lack of nutrient supply: The organic matter content is extremely low, typically less than 0.5%, and sometimes even below 0.1%. It lacks the basic organic nutrients necessary for plant growth and the cementing substances that form the soil structure. The content of mineral nutrients such as nitrogen, phosphorus, and potassium is extremely low, containing almost no nutrients that plants can absorb. Similarly, due to the simple mineral composition and lack of adsorption carriers, trace elements are also generally deficient. Furthermore, due to the lack of nutrients and water, and the harsh physical environment, the number and activity of microorganisms and animals (such as earthworms) in the soil are extremely low, which is detrimental to organic matter decomposition, nutrient cycling, and soil structure improvement.

[0004] 2. Extremely poor water and fertilizer retention capacity: It has many large pores, resulting in weak water retention and capillary action. After rainfall or irrigation, water quickly infiltrates and is lost, causing the soil surface to dry out rapidly. It also has weak adsorption capacity, lacking clay particles and organic colloids, making it poor at adsorbing applied fertilizers and the already scarce soluble nutrients in the soil, which are easily leached away with water.

[0005] 3. The physical structure is unstable and susceptible to wind and water erosion: The soil particles are loose and lack structure. There is a lack of cementing material between soil particles, and the soil structure is very loose. It has poor erosion resistance and is easily blown and transported by wind and water. This leads to the loss of topsoil (and the small amount of nutrients and seeds that may be present in it), forming erosion pits or burying sand.

[0006] 4. The plants are subjected to severe physical stress. Soil has a low specific heat capacity, causing its temperature to rise rapidly during the day after absorbing solar radiation, and it also dissipates heat quickly at night, resulting in a large diurnal temperature range and causing heat stress to plant roots and seedlings. Moving sand dunes or sandstorms can bury seedlings and vegetation. Sand particles in sandstorms can cause physical damage (abrasion, impact) to plant stems and leaves.

[0007] Primary soil can gradually improve its development through natural forces, but this process is extremely slow, often taking tens of thousands of years. Artificial intervention can significantly accelerate this process. In densely populated areas, primary soil typically undergoes hundreds or even thousands of years of continuous transformation to achieve a significant improvement in its development, transforming it into fertile land. A typical example is some red soils in South and Southwest my country. These red soils were initially poorly developed and infertile, unsuitable for crops or other vegetation; many were considered wasteland until the Ming Dynasty. With the construction of irrigation facilities, through repeated flooding and drainage, under cyclical wet-dry and redox conditions, these red soils quickly accumulated considerable organic matter. The soil's physical properties and profile characteristics changed accordingly, forming an infiltration layer with a core-mass structure, a crystalline membrane, and significant iron and manganese deposits. Although not yet fertile, it was already usable as arable land. After decades of cultivation and improvement, this land is now fertile paddy soil.

[0008] However, not all regions have the necessary irrigation conditions. In areas lacking these conditions, current technologies employ a combination of chemical amendments and vegetation restoration. By incorporating bentonite and carboxymethyl cellulose, which have binding properties, the soil can be quickly given a certain capacity to retain water and nutrients, allowing some well-developed root-forming plants to grow. However, the fertility of this amended soil remains limited for a considerable period, requiring regular topdressing for vegetation restoration. Furthermore, this approach consumes relatively expensive chemical substances.

[0009] Taking the research project on the mechanism and prevention strategies of various types of soil erosion under complex mountainous conditions, as an example, this project requires the improvement of aeolian sandy soil in Pai Town, Milin County, Nyingchi City. The project area is located in the Yarlung Tsangpo Grand Canyon, with extremely inconvenient transportation, and the local area lacks the capacity to produce fertilizers and chemical substances for soil improvement. Considering only the annual precipitation and sunshine conditions, the local climate is sufficient to support relatively lush vegetation. However, due to the uneven seasonal distribution of precipitation and the relatively dry winters, strong afternoon winds (especially after 3-4 pm) blow up exposed sand from the Yarlung Tsangpo River valley, forming sandstorms. At the same time, due to the large topographical drop, water erosion is also quite severe. This makes it impossible for vegetation to grow normally on the surface of the local aeolian sandy soil, and the topsoil is rapidly lost. Without human intervention, the ecological situation will further deteriorate. If conventional methods are used for restoration, the large amount of fertilizers and chemical agents required would need to be transported across the entire Qinghai-Tibet Plateau and the Grand Canyon, which is not feasible. Summary of the Invention

[0010] This invention provides a hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation and its application method.

[0011] The technical problem to be solved is that existing soil improvement methods that combine chemical modification with vegetation restoration require a large amount of fertilizer and chemical agents, which are costly and unsuitable for areas with poor transportation.

[0012] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a hydrolyzed polysaccharide-biofilm soil protectant for primary soil improvement, which uses various microbial agents and agricultural and forestry solid waste to improve primary soil, including aeolian sandy soil, in stages, and includes the following components: Acid-producing bacteria that enhance the weathering of minerals in the soil; Pectin organic matter is used to release hydrolyzed polysaccharides, mainly pectin, during the decomposition process as a fermentation substrate, causing soil particles to aggregate in a short period of time; the pectin organic matter includes crushed plant tender stems and leaves, including crushed waste fruits and vegetables, and / or crushed fruit. Biofilm-producing bacteria used to generate biofilms that aggregate soil particles after the depletion of hydrolyzed polysaccharides; Phosphorus- and potassium-solubilizing bacteria used to release insoluble nutrients from minerals; Long-lasting organic matter used to provide a long-lasting carbon source for various microbial agents and to collect pectin organic matter; the long-lasting organic matter is lignified plant stem powder and / or mature plant stem powder; Nitrogen-fixing bacteria used to regulate the carbon-to-nitrogen ratio.

[0013] Furthermore, the soil protectant is mixed into the top 10-20 cm of soil, and the concentration of each microbial species in the soil protectant, calculated in CFU, is not less than 10. 7 CFU / g, total viable bacteria concentration not less than 2×10 8 CFU / g.

[0014] Furthermore, the acid-producing bacteria include Trichoderma reesei and white-rot fungi used to treat long-lasting organic matter, acetic acid bacteria used to produce acetic acid, and Aspergillus niger used to produce citric acid and gluconic acid to form chelate salts and release hydrolyzed polysaccharides; both Aspergillus niger and acetic acid bacteria use pectin organic matter and long-lasting organic matter treated by Trichoderma reesei as fermentation substrates to produce acid. The nitrogen-fixing bacteria include Azotobacter chrysotrichum, which is used to regulate the carbon-nitrogen ratio before vegetation grows, and Rhizobium and Freundii, which are used to regulate the carbon-nitrogen ratio after vegetation grows. The film-forming bacteria is Bacillus subtilis, and the phosphorus-solubilizing and potassium-solubilizing bacteria is Bacillus mucilaginosus.

[0015] Furthermore, the proportion range of each microbial species in the soil protectant, calculated in CFU, is as follows: Acid-producing bacteria: 50-60% in total, of which: Trichoderma reesei: 12-18%; White rot fungi: 8-12%; Acetic acid bacteria: 10-15%; Aspergillus niger: 15-20%; Nitrogen-fixing bacteria: 25-30% in total, of which: Azotocinus chrysophytes: 15-20%; Rhizobium + Freundii: 5-10%; Film-forming bacteria: 5-10% in total, of which: Bacillus subtilis 5-10%; Phosphorus- and potassium-solubilizing bacteria: Total 5-10%, of which: 5-10% of Bacillus jellyii.

[0016] Furthermore, the soil protectant also includes oxygen channel organic matter to prevent oxygen deficiency inside the biofilm, wherein the oxygen channel organic matter is rice husk and / or broken peanut shells.

[0017] Furthermore, by mass, the mass ratio of the pectin organic matter, long-acting organic matter, and oxygen channel organic matter is 15-25:80:5.

[0018] The method of using the hydrolyzed polysaccharide-biofilm soil protectant for primary soil improvement includes the following steps: Step 1: Crush the pectin organic matter and long-lasting organic matter together; Step 2: Add the microbial agent to the mixture from Step 1 and mix well to form a soil protectant; Step 3: Depending on the working conditions, different methods are used to mix the soil protectant into the soil: Application 1: Used for in-situ soil improvement, the soil protectant is mixed into the topsoil by rotary tillage; Working condition 2: For improvement after topsoil stripping, a soil protectant is mixed into the stripped soil using a mixer.

[0019] Furthermore, in step two, the film-forming bacteria are mixed in as unactivated powder, while the remaining bacteria are mixed in as live bacterial solution or activated powder suspension.

[0020] Furthermore, in working condition one, 1.7-2.5 tons of soil protectant are added per acre; In working condition two, 115-168 kg of soil protectant is added to each ton of soil stripped off; and if the soil pile thickness exceeds 20 cm, aeration pipes are inserted into the soil to avoid deep oxygen deficiency affecting acid production.

[0021] Compared with existing technologies, the hydrolyzed polysaccharide-biofilm soil protectant and its application method of this invention have the following advantages: In this invention, soil particles are rapidly aggregated by utilizing the abundant hydrolyzed polysaccharides, primarily pectin, produced during the degradation of waste fruits and vegetables (regardless of their edibility, including rotten, wild, toxic, and unpalatable plant stems, leaves, and fruits) by microorganisms, including acid-producing bacteria. This process resists wind and water erosion while allowing fungal hyphae to attach. The organic acids, as byproducts, react with soil minerals with low weathering levels, rapidly increasing mineral weathering without causing soil acidification and releasing some of the nutrients from the minerals.

[0022] After the easily degradable sugars in the discarded fruits and vegetables are depleted, the dried plant stem powder mixed into the soil along with the discarded fruits and vegetables has been decomposed by Trichoderma reesei and white rot fungi, and can be utilized by other microorganisms. In addition, the nutrients released from the minerals in the early stage, as well as the nitrogen-carbon ratio regulated by nitrogen-fixing bacteria, can maintain the growth of engineered bacteria such as biofilm-producing bacteria and phosphorus- and potassium-solubilizing bacteria for a long time. This allows for the continuous production of biofilm to maintain the aggregation of soil particles and the continuous release of nutrients from soil minerals to maintain fertility. This supports vegetation growth to maintain the supply of organic matter and establishes a long-term sustainable soil ecological cycle.

[0023] By combining the above points, the improvement of the initial soil can be achieved without consuming a large amount of chemical agents and fertilizers (all raw materials except for the microbial agent can be sourced locally, and the amount of microbial agent used is small and easy to expand, and it is not affected by poor transportation). Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating the changes that occur in the soil during the process of improving soil using the hydrolyzed polysaccharide-biofilm soil protectant and its application method of the present invention; Detailed Implementation Taking the research project on the mechanism and prevention strategies of various types of soil erosion under complex mountainous conditions, which proposes to use this invention for soil improvement, as an example, the hydrolyzed polysaccharide-biofilm soil protectant used in the initial soil cultivation employs various microbial agents and agricultural and forestry solid waste, such as... Figure 1 The method shown is to improve the primary soil, including aeolian sandy soil, in stages, and includes the following components: Acid-producing bacteria that enhance the weathering of minerals in the soil; The initial soil contains very low levels of various inorganic salts. Therefore, acid-producing bacteria are needed to first corrode the minerals in the soil particles, increasing the weathering degree of the soil minerals and releasing enough inorganic salts to support the subsequent growth of microorganisms. These inorganic salts are generally not strictly inorganic substances; their anions are usually organic acid radicals (some also release hydrogen phosphate due to pH changes), which can serve as a readily available carbon source for other microorganisms. Their cations include a variety of elements such as sodium, potassium, calcium, iron, and manganese, covering the various trace elements needed for microbial growth (pectin organic matter also contains some, but only enough for acid-producing bacteria), and also includes elements such as phosphorus and potassium that are important for plants. Fruits and vegetables release a large amount of organic acids during decomposition, which can have adverse effects in conventional soil. However, in the initial soil, these organic acids are consumed and can even have positive effects.

[0025] Pectin organic matter is used to release hydrolyzed polysaccharides, mainly pectin, during the decomposition process as a fermentation substrate, causing soil particles to aggregate in a short period of time; pectin organic matter includes crushed plant tender stems and leaves, including crushed waste fruits and vegetables, and / or crushed fruit. Pectin is a gelatinous substance found abundantly in the primary cell walls of plants (corresponding to vegetables) and fruits. When released into the soil, it can quickly aggregate soil particles. In addition to pectin, fruits and vegetables also contain easily degradable polysaccharides such as starch and hemicellulose. During their degradation process, these polysaccharides also produce oligosaccharides, which similarly contribute to agglomerating soil particles.

[0026] Since their edibility is not considered, the discarded fruits and vegetables here include rotten, wild, poisonous, and inedible tender stems, leaves, and fruits. The term "discarded fruits and vegetables" is used as a general term because the concept of vegetables basically includes almost all tender stems and leaves of plants that humans can easily collect. However, most of these are generally not considered for consumption due to their unpalatability or toxicity, and are only considered as vegetables during times of food scarcity; thus, they are considered "discarded" vegetables. In addition, many wild fruits ripen in concentrated seasons, far exceeding the needs of local wild animals and humans. Most of these fall to the ground and rot, and these are also usable resources. In this embodiment, when collecting these materials locally, in addition to collecting discarded fruits and vegetables from the nearby Milin Farm, pig feed (tender grass for feeding pigs), wild fruits, and fruit peels (including watermelon rinds) are also collected.

[0027] Biofilm-producing bacteria used to generate biofilms that aggregate soil particles after the depletion of hydrolyzed polysaccharides; Hydrolyzed polysaccharides such as pectin can aggregate soil particles in a short time, but they are also metabolized. Therefore, other methods are needed to aggregate soil particles. In this embodiment, biofilm-producing bacteria are used to achieve this. These bacteria can secrete extracellular polymers to produce biofilms, which aggregate soil particles. In addition, the organic acids secreted by acid-producing bacteria corrode soil minerals to produce some soluble calcium salts. These calcium salts subsequently undergo a series of reactions to become insoluble calcium salts, which also contribute to the aggregation of soil particles.

[0028] Phosphorus- and potassium-solubilizing bacteria used to release insoluble nutrients from minerals; Phosphorus and potassium solubilizing bacteria are commonly used microbial fertilizers that release phosphorus and potassium fertilizers from minerals such as potassium feldspar and apatite (acid-producing bacteria also have some effect, but not as much as phosphorus and potassium solubilizing bacteria). These microbial fertilizers have high soil requirements and are not effective initially. However, after the soil is treated with acid-producing bacteria, the soil contains organic acids and organic acid salts, and soil particles aggregate, allowing these phosphorus and potassium solubilizing bacteria to grow and continuously improve soil fertility.

[0029] Long-lasting organic matter used to provide a long-lasting carbon source for various microbial agents and to collect pectin organic matter; the long-lasting organic matter is lignified plant stem powder and / or mature plant stem powder. Pectin organic matter metabolizes very quickly. Once it is depleted, heterotrophic microorganisms in the soil lack a carbon source. Therefore, a long-lasting carbon source is needed. Slow-degrading organic matter such as hay powder, straw powder, and chopped branches can be used. In addition to providing a carbon source for microorganisms, another function of long-lasting organic matter is to adsorb pectin organic matter, preventing it from clumping together after being crushed and thus failing to be evenly incorporated into the soil.

[0030] Nitrogen-fixing bacteria are used to regulate the carbon-nitrogen ratio. These bacteria not only provide nitrogen fertilizer for plants after they grow, but more importantly, they regulate the carbon-nitrogen ratio to ensure that various microorganisms do not fail to grow normally due to an imbalance in the carbon-nitrogen ratio in the fermentation substrate (too low nitrogen content in long-lasting organic matter can easily lead to an imbalance in the carbon-nitrogen ratio).

[0031] In this embodiment, the soil protectant is mixed into the top 10-20 cm of soil. This topsoil layer has the greatest soil improvement value. In the deeper soil layers, there are relatively fewer plant roots, and the improvement effect on vegetation growth is small.

[0032] The concentration of each microbial species in the soil protectant, calculated in CFU, is not less than 10. 7 CFU / g, total viable bacteria concentration not less than 2×10 8 CFU / g. This ensures that each microorganism quickly reaches the required population size.

[0033] In this embodiment, the acid-producing bacteria include Trichoderma reesei and white-rot fungi used to treat long-lasting organic matter, acetic acid bacteria used to produce acetic acid, and Aspergillus niger used to produce citric acid and gluconic acid to form chelate salts and release hydrolyzed polysaccharides; both Aspergillus niger and acetic acid bacteria use pectin organic matter and long-lasting organic matter treated by Trichoderma reesei as fermentation substrates to produce acid. Acetic acid bacteria and Aspergillus niger can rapidly produce large quantities of organic acids, most of which are soluble, thus ensuring effective weathering of soil minerals. Some acetates are insoluble or even unstable in water (such as aluminum acetate), in which case citric acid and gluconic acid are used to form chelate salts. In addition, Aspergillus niger also produces some hydrolyzed polysaccharides.

[0034] Trichoderma reesei and white-rot fungi can also secrete organic acids, but in smaller quantities. These two fungi are primarily used here to process long-lasting organic matter, breaking it down into smaller molecular weight organic compounds for use by other fungi. White-rot fungi can decompose lignin, while Trichoderma reesei can efficiently decompose cellulose.

[0035] In this embodiment, nitrogen-fixing bacteria include Azotobacter chrysotrichum, which is used to regulate the carbon-nitrogen ratio before vegetation grows, and Rhizobium and Freundii, which are used to regulate the carbon-nitrogen ratio after vegetation grows. Here, *Azotobacter chrysoprase* is a non-symbiotic nitrogen-fixing bacterium that uses organic matter in the soil to grow and fix nitrogen, thereby regulating the carbon-nitrogen ratio in the soil before vegetation grows. After vegetation grows, more efficient symbiotic nitrogen-fixing bacteria can be used for nitrogen fixation, such as rhizobia that live in symbiosis with the roots of leguminous plants and *Fructus freundii* that live in symbiosis with the roots of non-leguminous plants.

[0036] In this embodiment, the film-forming bacteria is Bacillus subtilis, and the phosphorus-solubilizing and potassium-solubilizing bacteria is Bacillus mucilaginosa.

[0037] Bacillus subtilis is a versatile organism with some nitrogen-fixing and phosphorus and potassium-solubilizing abilities, though not strong. Its notable ability is its efficient secretion of extracellular polymeric substances (EPS), rapidly generating biofilms to aggregate soil particles. This ability to produce EPS can be observed in everyday life, such as in natto, a sticky soybean product made using Bacillus subtilis fermentation. Meanwhile, Bacillus mucilaginosus possesses a strong ability to decompose minerals to produce soluble potassium salts, and also exhibits considerable phosphorus-solubilizing capabilities.

[0038] Considering the metabolic status, efficacy stages, and synergistic effects of different microbial species, and based on calculations and multiple experiments, the following are relatively effective microbial ratios. The proportions of each microbial species in the soil protectant, expressed in CFU, are shown in the table below: Table 1: Range of Proportions of Various Microbial Species in Soil Protectants These ranges are taken into account that it is impossible to be very precise when mixing different strains, but as long as they are within these ranges, there will be a good effect on soil improvement.

[0039] All the bacterial species in this embodiment are aerobic bacteria. The soil protectant also includes oxygen-channel organic matter to prevent oxygen deficiency inside the biofilm. The oxygen-channel organic matter is rice husk and / or broken peanut shells. Rice husk contains a large amount of phytoliths, while peanut shell is an organic matter that is extremely difficult to metabolize. Therefore, these two organic materials can exist in the soil for a long time. At the same time, because rice husk is hollow and peanut shell has micropores, they can embed themselves in the biofilm and transfer oxygen into the biofilm.

[0040] In this embodiment, the mass ratio of pectin organic matter, long-acting organic matter, and oxygen channel organic matter is 15-25:80:5.

[0041] Too much pectin and organic matter will prevent soil protectants from being properly mixed into the soil, while too little will result in insufficient agglomeration of soil particles in the early stages.

[0042] The method of using the hydrolyzed polysaccharide-biofilm soil protectant for primary soil improvement includes the following steps: Step 1: Crush the pectin organic matter and long-lasting organic matter together; Step 2: Add the microbial agent to the mixture from Step 1 and mix well to form a soil protectant; Step 3: Depending on the working conditions, different methods are used to mix the soil protectant into the soil: Application 1: Used for in-situ soil improvement, the soil protectant is mixed into the topsoil by rotary tillage; Working condition 2: For improvement after topsoil stripping, a soil protectant is mixed into the stripped soil using a mixer.

[0043] In step two, the biofilm-producing bacteria are mixed in as an unactivated powder, while the remaining bacteria are mixed in as a live bacterial solution or an activated powder suspension. Biofilms can reduce mass transfer efficiency in the soil to some extent, so the biofilm-producing bacteria are not suitable for their initial function; therefore, they should be mixed in as an unactivated form to participate in soil metabolism later.

[0044] In working condition one, 1.7-2.5 tons of soil protectant should be added per acre; In working condition two, 115-168 kg of soil protectant is mixed into each ton of soil stripped off; The cost of this soil protectant is very low; it can even be considered a special type of organic fertilizer (although its composting process takes place in situ in the soil and utilizes some special microorganisms), so its dosage is comparable to that of organic fertilizer.

[0045] If the soil mound is more than 20 cm thick, aeration pipes should be inserted into the soil to prevent deep-layer oxygen deficiency from affecting acid production. The microorganisms used in this invention are all aerobic, therefore, it is important to prevent these microorganisms from experiencing oxygen deficiency.

[0046] This invention is intended for the improvement of wind-blown sandy soil in Pai Town, Milin County, Nyingchi City. 50 kg of topsoil samples were extracted from local sandy soil plots. A soil protectant with a 12% wt content was added to the topsoil samples, and the proportions of various microorganisms in the soil protectant were within the ranges shown in Table 1. From April 10th to May 10th, 2025, the soil samples underwent continuous composting. After fermentation, the soil was measured, and the results showed that the soil humus content was significantly increased, the soil aggregate structure was significantly improved, the bulk density was reduced, the porosity was increased, the soil water-holding capacity was enhanced, the pH tended to be neutral, and the wind erosion coefficient was significantly reduced. Transplanting typical local plants into the improved soil showed a survival rate of over 95%, with vigorous plant growth, normal leaf color, and well-developed root systems. Under the same conditions, the control group could not grow normally; approximately 70% survived in the early stages of transplanting, but later, due to the lack of soil water and fertilizer retention capacity, most plants failed to grow normally. By the end of August, the surviving plant content was less than 10% wt.

[0047] Experimental results show that the present invention can effectively improve sandy soil, enhance soil fertility, and increase plant survival and growth rate.

[0048] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation, characterized in that: A variety of microbial agents and agricultural and forestry solid waste are used to improve the initial soil, including aeolian sandy soil, in stages. The soil includes the following components: Acid-producing bacteria that enhance the weathering of minerals in the soil; Pectin organic matter is used to release hydrolyzed polysaccharides, mainly pectin, during the decomposition process as a fermentation substrate, causing soil particles to aggregate in a short period of time; the pectin organic matter includes crushed plant tender stems and leaves, including crushed waste fruits and vegetables, and / or crushed fruit. Biofilm-producing bacteria used to generate biofilms that aggregate soil particles after the depletion of hydrolyzed polysaccharides; Phosphorus- and potassium-solubilizing bacteria used to release insoluble nutrients from minerals; Long-lasting organic matter used to provide a long-lasting carbon source for various microbial agents and to collect pectin organic matter; the long-lasting organic matter is lignified plant stem powder and / or mature plant stem powder; Nitrogen-fixing bacteria used to regulate the carbon-to-nitrogen ratio.

2. The hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation according to claim 1, characterized in that: The soil protectant is mixed into the top 10-20 cm of soil, and the concentration of each microbial species in the soil protectant, calculated in CFU, is not less than 10. 7 CFU / g, total viable bacteria concentration not less than 2×10 8 CFU / g.

3. The hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation according to claim 2, characterized in that: The acid-producing bacteria include Trichoderma reesei and white-rot fungi used to treat long-lasting organic matter, acetic acid bacteria used to produce acetic acid, and Aspergillus niger used to produce citric acid and gluconic acid to form chelate salts and release hydrolyzed polysaccharides; both Aspergillus niger and acetic acid bacteria use pectin organic matter and long-lasting organic matter treated by Trichoderma reesei as fermentation substrates to produce acid. The nitrogen-fixing bacteria include Azotobacter chrysotrichum, which is used to regulate the carbon-nitrogen ratio before vegetation grows, and Rhizobium and Freundii, which are used to regulate the carbon-nitrogen ratio after vegetation grows. The film-forming bacteria is Bacillus subtilis, and the phosphorus-solubilizing and potassium-solubilizing bacteria is Bacillus mucilaginosus.

4. The hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation according to claim 3, characterized in that: The proportions of each microbial species in the soil protectant, calculated in CFU, are as follows: Acid-producing bacteria: 50-60% in total, of which: Trichoderma reesei: 12-18%; White rot fungi: 8-12%; Acetic acid bacteria: 10-15%; Aspergillus niger: 15-20%; Nitrogen-fixing bacteria: 25-30% in total, of which: Azotocinus chrysophytes: 15-20%; Rhizobium + Freundii: 5-10%; Film-forming bacteria: 5-10% in total, of which: Bacillus subtilis 5-10%; Phosphorus- and potassium-solubilizing bacteria: Total 5-10%, of which: 5-10% of Bacillus jellyii.

5. The hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation according to claim 1, characterized in that: The soil protectant also includes oxygen channel organic matter to prevent oxygen deficiency inside the biofilm, wherein the oxygen channel organic matter is rice husk and / or broken peanut shell.

6. The hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation according to claim 5, characterized in that: The mass ratio of the pectin organic matter, long-acting organic matter, and oxygen channel organic matter is 15-25:80:

5.

7. A method for using hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation, characterized in that: The method of improving soil by using the hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation as described in claim 3 includes the following steps: Step 1: Crush the pectin organic matter and long-lasting organic matter together; Step 2: Add the microbial agent to the mixture from Step 1 and mix well to form a soil protectant; Step 3: Depending on the working conditions, different methods are used to mix the soil protectant into the soil: Application 1: Used for in-situ soil improvement, the soil protectant is mixed into the topsoil by rotary tillage; Working condition 2: For improvement after topsoil stripping, a soil protectant is mixed into the stripped soil using a mixer.

8. The method of using the hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation according to claim 7, characterized in that: In step two, the film-forming bacteria are mixed in as unactivated powder, while the remaining bacteria are mixed in as live bacterial solution or activated powder suspension.

9. The method of using the hydrolyzed polysaccharide-biofilm soil protectant for primary soil cultivation according to claim 7, characterized in that: In working condition one, 1.7-2.5 tons of soil protectant should be added per acre; In working condition two, 115-168 kg of soil protectant is added to each ton of soil stripped off; and if the soil pile thickness exceeds 20 cm, aeration pipes are inserted into the soil to avoid deep oxygen deficiency affecting acid production.

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