A microbial improvement and cultivation integrated method and system for saline-alkali soil

Abstract

The application relates to the technical field of soil improvement, and discloses a microbial improvement and cultivation integrated method and system for saline-alkali soil, which comprises the following steps: performing multi-point sampling detection on target saline-alkali soil to obtain the soil salt content of each sampling point, dividing the target saline-alkali soil into different types of saline-alkali regions based on the soil salt content; generating functional microbial flora and biological organic products for different types of saline-alkali regions based on the soil nutrient parameters of the target saline-alkali soil; mixing the functional microbial flora and the biological organic products in a mass ratio to obtain microbial soil improvers for different types of saline-alkali regions; identifying heavy clay regions in the target saline-alkali soil, performing deep layering treatment on the heavy clay regions, and obtaining a loose cultivation layer of the target saline-alkali soil; uniformly applying the microbial soil improvers to the loose cultivation layer to obtain an improved layer of the target saline-alkali soil, and performing cultivation treatment on the improved layer. The application can improve the efficiency of saline-alkali soil improvement and cultivation.

Description

Technical Field

[0001] This invention relates to the field of soil improvement technology, and in particular to an integrated method and system for microbial improvement and cultivation of saline-alkali land. Background Technology

[0002] Saline-alkali land is an important reserve of arable land for global agricultural development. It is widely distributed in many regions of my country, including the Bohai Rim, coastal areas of northern Jiangsu, and inland areas of Northwest China. The rational improvement and utilization of saline-alkali land is of great significance for increasing arable land area and ensuring food security. The core requirement of saline-alkali land improvement technology is to solve problems such as soil salt enrichment, nutrient deficiency, microbial community imbalance, and poor soil structure, so as to improve soil fertility and promote normal crop growth.

[0003] Among existing saline-alkali land improvement technologies, physical improvement methods mostly rely on simple deep plowing and drainage for short-term desalination, but they do not consider the differences in soil salinity distribution, resulting in uneven desalination effects and failing to improve soil nutrient status and microbial ecology. Chemical improvement methods often use chemical reagents such as gypsum to neutralize soil alkalinity, but this easily causes secondary soil pollution and fails to tailor solutions to the nutrient needs of different saline-alkali areas. Although biological improvement methods have attempted to apply microbial agents, strain screening lacks specificity, and functional verification is not conducted in conjunction with the differences between saline-alkali farmland systems and natural systems. Furthermore, the combination of microbial agents and organic matter lacks scientific ratio, resulting in low colonization rates and poor nutrient activation effects, which severely limits the efficiency and large-scale application of saline-alkali land improvement. Summary of the Invention

[0004] This invention provides an integrated method and system for microbial improvement and cultivation of saline-alkali land, the main purpose of which is to solve the problem of low efficiency in saline-alkali land improvement and cultivation.

[0005] To achieve the above objectives, the present invention provides an integrated method for microbial improvement and cultivation of saline-alkali land, comprising:

[0006] Multiple sampling and testing were conducted on the target saline-alkali land to obtain the soil salinity content at each sampling point. Based on the soil salinity content, the target saline-alkali land was divided into different types of saline-alkali zones.

[0007] Based on the soil nutrient parameters of the target saline-alkali land, functional microbial communities and biological organic products for the different types of saline-alkali areas were screened and generated respectively.

[0008] The functional microbial community and the biological organic products are mixed in a mass ratio to obtain a microbial soil conditioner for the different types of saline-alkali areas.

[0009] Identify the heavy clay texture area in the target saline-alkali land, perform deep stratification on the heavy clay texture area, and obtain the loose topsoil layer of the target saline-alkali land.

[0010] The microbial soil conditioner is uniformly applied to the loose topsoil layer to obtain the improved layer of the target saline-alkali land, and the improved layer is then tilled.

[0011] To address the aforementioned problems, the present invention also provides an integrated system for microbial improvement and cultivation of saline-alkali land, the system comprising:

[0012] The saline-alkali area division module is used to perform multi-point sampling and detection on the target saline-alkali land, obtain the soil salinity content at each sampling point, and divide the target saline-alkali land into different types of saline-alkali areas based on the soil salinity content.

[0013] The functional microbial community screening and generation module is used to screen and generate functional microbial communities and biological organic products for different types of saline-alkali areas based on the soil nutrient parameters of the target saline-alkali land.

[0014] A microbial soil conditioner generation module is used to mix the functional microbial community and the biological organic products in a mass ratio to obtain a microbial soil conditioner for the different types of saline-alkali areas.

[0015] The deep stratification processing module is used to identify the heavy clay texture area in the target saline-alkali land, perform deep stratification processing on the heavy clay texture area, and obtain the loose topsoil layer of the target saline-alkali land.

[0016] The tillage treatment module is used to uniformly apply the microbial soil conditioner to the loose tillage layer to obtain an improved layer of the target saline-alkali land, and to perform tillage treatment on the improved layer.

[0017] This invention addresses the problem of inaccurate saline-alkali zone identification by employing multi-point sampling and testing that combines farmland and natural systems in target saline-alkali land. Based on soil nutrient parameters, salt-tolerant microbial strains are selectively isolated, validated for compatibility, and cultured in combination. Simultaneously, targeted preparation of bio-organic products achieves precise matching between microbial communities and organic matter, improving nutrient activation efficiency and microbial colonization stability. A specialized microbial soil conditioner is obtained through the scientific mixing of functional microbial communities and bio-organic products, avoiding the limited effectiveness of single conditioners. Accurate identification and deep stratification of heavy clay soil areas effectively improves soil structure, enhancing aeration and water retention. Uniform application of the conditioner to the loose topsoil followed by tillage achieves synergistic effects between microbial improvement and tillage, significantly reducing soil salinity stress and improving soil fertility and crop growth suitability. Therefore, the integrated method and system for microbial improvement and tillage of saline-alkali land proposed in this invention can solve the problem of low efficiency in saline-alkali land improvement and tillage. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating an embodiment of the integrated microbial improvement and cultivation method for saline-alkali land provided by the present invention.

[0019] Figure 2 This is a functional module diagram of an integrated microbial improvement and cultivation system for saline-alkali land provided in an embodiment of the present invention.

[0020] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0022] This application provides a method for integrating microbial improvement and cultivation of saline-alkali land. The executing entity of this method includes, but is not limited to, at least one electronic device configured to execute the method provided in this application, such as a server or a terminal. In other words, the method can be executed by software or hardware installed on a terminal or server device, and the software may be a blockchain platform. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cluster of cloud servers. The server can be an independent server or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDNs), and big data and artificial intelligence platforms.

[0023] Reference Figure 1 The diagram shown is a flowchart illustrating an integrated method for microbial improvement and cultivation of saline-alkali land according to an embodiment of the present invention. In this embodiment, the integrated method for microbial improvement and cultivation of saline-alkali land includes:

[0024] S1. Conduct multi-point sampling and testing on the target saline-alkali land to obtain the soil salinity content at each sampling point, and divide the target saline-alkali land into different types of saline-alkali zones based on the soil salinity content.

[0025] In this embodiment of the invention, the target saline-alkali land refers to a land area with soil salt accumulation and high pH value, which affects the normal growth of crops, such as the Nandagang coastal saline-alkali soil area in Huanghua City, Hebei Province. Soil salt content refers to the total content of soluble salts in the soil, which is a core indicator reflecting the degree of soil salinization. For example, the water-soluble salt content of the tested soil in Nandagang, Huanghua, was 2.08 g / kg.

[0026] In this embodiment of the invention, the step of performing multi-point sampling and detection on the target saline-alkali land to obtain the soil salinity content at each sampling point includes:

[0027] Representative research units were selected within the target saline-alkali land area, with each research unit containing farmland system soils and natural system soils;

[0028] Sampling points were configured in the research unit according to the preset spatial grid distribution principle, and soil samples were collected from each sampling point;

[0029] The soil samples were tested for salinity to obtain the salinity of the soil at each sampling point.

[0030] In detail, the selection of research units needs to comprehensively consider the topography, soil type, and salinization degree distribution of the target saline-alkali land to ensure that the selected research units can fully reflect the soil conditions of the entire target saline-alkali land. For example, in the Huanghua Nandagang coastal saline-alkali farmland demonstration area (approximately 60 mu), three research units were selected, corresponding to areas with mild, moderate, and severe salinization, respectively. Within each research unit, farmland system soil areas (such as cultivated land planted with Jiemai 19 wheat and Nongda 372 corn) and natural system soil areas (non-saline-alkali areas) were simultaneously delineated. Both types of soil maintained consistency in terms of topographic slope, soil layer thickness, and other natural conditions to ensure the scientific validity of subsequent comparative analysis. The spatial grid distribution principle was determined based on the area size of the research unit. For example, for a research unit with an area of ​​14 mu in the Huanghua Nandagang demonstration area, a grid spacing of 20 meters × 20 meters was used to divide the grid, and a five-point sampling method was used to select sampling points to ensure even distribution of sampling points. Soil profile sampling was employed, using a soil auger to collect soil samples from the 0-40cm soil layer. This layer is the primary distribution area for crop roots, and its salinity has the most significant impact on crop growth. During the collection process, three parallel samples were collected from each sampling point. Plant debris, stones, and other impurities were removed from the samples, which were then placed in sealed bags and labeled with the sampling point location, collection time, and other information. For example, soil samples collected from the L2 sampling point in the low-salinity area had a pH of 7.50, an EC value of 120.2 μS / cm, a sodium ion content of 30 mg / kg, and a chloride ion content of 32 mg / kg in the 0-20cm soil layer. This ensured the homogeneity and representativeness of the soil samples, guaranteeing the accuracy of subsequent salinity content testing results.

[0031] Specifically, before testing, soil samples were air-dried, ground, and sieved through a 2 mm sieve. Soil extracts were prepared at a soil-to-water ratio of 1:5. The conductivity of the extracts was measured using a conductivity meter, and the soil salinity was calculated using a conversion formula. For example, the conductivity of the soil extract from sampling point L3 in the low-salinity area of ​​the Huanghua Nandagang Demonstration Zone was 123.2 μS / cm, which was converted to a soil salinity of 2.1 g / kg; the conductivity of the soil extract from sampling point M2 in the medium-salinity area was 356.0 μS / cm, which was converted to a soil salinity of 5.5 g / kg. Simultaneously, the content of soluble salt ions such as sodium, chloride, and sulfate ions in the extracts was detected using instruments such as flame photometry and ion chromatography. For example, the sodium ion content at sampling point H3 in the medium-salinity area was 296 mg / kg, the chloride ion content was 238 mg / kg, and the sulfate ion content was 149 mg / kg, helping to determine the main causes of soil salinization.

[0032] In this embodiment of the invention, different types of saline-alkali areas include low-salinity areas, medium-salinity areas, and high-salinity areas. For example, in the Huanghua Nandagang Demonstration Area, the low-salinity area is set at 1-3 g / kg, and the medium-salinity area at 3-6 g / kg.

[0033] In this embodiment of the invention, dividing the target saline-alkali land into different types of saline-alkali zones based on the soil salinity content includes:

[0034] The soil salinity content at each sampling point is compared with the preset soil salinity threshold range;

[0035] Based on the comparison results and the biodiversity and functional dominant factors of the target saline-alkali land, the target saline-alkali land is divided into different types of areas;

[0036] The spatial boundary information of the different types of regions is identified, and supplementary sampling and detection are performed on the different types of regions based on the spatial boundary information to obtain different types of saline-alkali areas.

[0037] In detail, the threshold range for soil salinity was determined based on crop growth requirements and saline-alkali land improvement practices. Referring to the soil conditions of the Huanghua Nandagang Demonstration Area, the threshold range for low-salt stress areas was set at 1-3 g / kg, and the threshold range for medium-salt stress areas was set at 4-6 g / kg. The soil salinity content of each sampling point was matched against the threshold range to preliminarily determine the type of saline-alkali area to which each sampling point belonged. For example, the soil salinity content at sampling point L2 in the Huanghua Nandagang Demonstration Area was 1.3 g / kg, preliminarily identified as a low-salt stress area; the soil salinity content at sampling point M2 was 5.2 g / kg, preliminarily identified as a medium-salt stress area. High-throughput sequencing and quantitative real-time PCR were used to analyze the microbial diversity of the soil at each sampling point, determining the types and quantities of functional microorganisms such as phosphate-solubilizing bacteria, nitrogen-fixing bacteria, and salt-tolerant fungi, i.e., biodiversity and dominant functional factors. For example, the number of nitrogen-fixing bacteria at sampling point L3 in the low-salt-alkali area of ​​the Huanghua Nandagang Demonstration Area was 2.5 × 10⁻⁶. 6 CFU / g, phosphate-solubilizing bacteria count was 3.2 × 10⁻⁶. 7 The CFU / g level indicates high microbial diversity; the nitrogen-fixing bacteria count at sampling point M2 in the medium-salt-alkali area is 1.1 × 10⁻⁶. 6 CFU / g, phosphate-solubilizing bacteria count was 1.5 × 10⁻⁶. 7 The CFU / g level was low, indicating low microbial diversity. Combining the comparative results with biodiversity and dominant functional factors, a more detailed regional division was made for the target saline-alkali land. For example, areas with abundant functional microorganisms and high soil organic matter content (e.g., 1.58% organic matter content at sampling point L3) in low-salinity areas were designated as suitable low-salinity planting areas, while areas with fewer functional microorganisms were designated as low-salinity areas requiring improvement. This improved the scientific rigor of the saline-alkali land division.

[0038] Specifically, using a geographic information system (GIS), the coordinates of each sampling point and its corresponding regional type are entered into the system to generate spatial distribution maps of different regional types, thereby identifying the spatial boundary information of each region. For example, the western part of the Huanghua Nandagang Farmland Demonstration Area is a low-salinity area, with boundary coordinates from X1-Y1 to X2-Y2, while the eastern part is a medium-salinity area, with boundary coordinates from X2-Y2 to X3-Y3. For areas with ambiguous boundaries or transitional zones, supplementary sampling points are set at 5-meter intervals to collect soil samples and conduct salinity and biodiversity tests. For instance, at the boundary between the low-salinity and medium-salinity areas, five additional soil samples are collected. Three of these samples have a salinity of 2.8-6.2 g / kg. By testing the number and activity of functional microorganisms, the area with a salinity of 6.0 g / kg and low functional microbial activity is ultimately classified as a medium-salinity area. By supplementing sampling and testing, the initial classification results were corrected, and finally, different types of saline-alkali areas with clear boundaries and distinct characteristics were obtained. This solved the problem of inaccurate boundary delineation of saline-alkali areas and provided accurate spatial basis for the implementation of subsequent customized improvement schemes.

[0039] For example, in the sample plot layout of the Nandagang Farmland Demonstration Area in Huanghua, Hebei Province, the spatial distribution, boundary range, and area of ​​the low-salinity zone (west of the demonstration area, with a salt content of approximately 0.1%) and the medium-salinity zone (east of the demonstration area, with a salt content of over 0.3%) were clearly defined. This demonstrates the actual spatial layout of the saline-alkali zone division, verifies the scientific validity and operability of the division, and provides clear spatial guidance for subsequent targeted application of soil amendments and cultivation treatments.

[0040] Furthermore, different types of saline-alkali areas differ in their soil nutrient requirements and the suitability of salt-tolerant microorganisms. For example, low-salt-alkali areas have relatively sufficient nitrogen and phosphorus nutrients in their soils, so it is necessary to focus on improving microbial activity. Medium-salt-alkali areas have scarce soil nutrients and severe salt-alkali stress, so it is necessary to strengthen both nutrient supplementation and salt tolerance and alkali reduction functions. Therefore, it is necessary to generate functional microbial communities and biological organic products in a targeted manner based on the soil nutrient parameters of each saline-alkali area in order to achieve precise improvement.

[0041] S2. Based on the soil nutrient parameters of the target saline-alkali land, functional microbial communities and biological organic products for the different types of saline-alkali areas are screened and generated respectively.

[0042] In this embodiment of the invention, soil nutrient parameters refer to indicators reflecting soil nutrient status, including the content levels of soil nitrogen, phosphorus, organic matter, etc., such as the organic matter content of 21.6 g / kg, total nitrogen content of 1.25 g / kg, and available phosphorus content of 19.0 mg / kg in the tested soil from Nandagang, Huanghua. Functional microbial communities refer to microbial communities composed of various microbial strains with specific functions, capable of synergistically improving soil salinity and nutrient levels. Bio-organic products refer to organic materials that, after acidity adjustment and nutrient testing, can be used in conjunction with functional microbial communities.

[0043] In this embodiment of the invention, the process of screening and generating functional microbial communities and bio-organic products for different types of saline-alkali areas based on soil nutrient parameters of the target saline-alkali land includes:

[0044] Based on the soil nutrient parameters, the nutrient levels of soil samples from different types of saline-alkali areas are determined, and the nutrient activation function direction of the microbial community is determined based on the nutrient levels.

[0045] Salt-tolerant microbial strains were isolated from the soil sample based on the direction of nutrient activation function;

[0046] The compatibility of the salt-tolerant microbial strains was verified before mixing, and the salt-tolerant microbial strains that passed the compatibility verification were cultured in combination to obtain functional microbial communities for different types of saline-alkali areas.

[0047] The carbon source replenishment requirements of biological organic products are determined based on the soil organic matter content parameters of different types of saline-alkali areas in the target saline-alkali land, and basic raw materials are selected based on the organic matter composition of the natural system soils of different types of saline-alkali areas.

[0048] The ratio of the basic raw materials is adjusted according to the carbon source replenishment requirements, and the ratiod basic raw materials are subjected to aerobic fermentation to obtain the initial organic product.

[0049] The initial organic matter was subjected to acid-adjusted treatment, and the nutrient content of the adjusted organic product was detected to obtain the bio-organic product.

[0050] In detail, the Kjeldahl method was used to determine the total nitrogen content of soil samples, the molybdenum-antimony colorimetric method was used to determine the total phosphorus content, and the potassium dichromate oxidation-external heating method was used to determine the organic matter content, thus obtaining soil nutrient parameters. For example, the total nitrogen content of sampling point L2 in the low-salinity and alkaline area of ​​Huanghua Nandagang was 0.14%, the total phosphorus content was 917.94 mg / kg, and the organic matter content was 6.06 g / kg, which was judged as moderate nutrient content; the total nitrogen content of sampling point M2 in the medium-salinity and alkaline area was 0.14%, the total phosphorus content was 956.48 mg / kg, and the organic matter content was 6.94 g / kg, which was judged as nutrient deficiency. Based on the test results, nutrient levels were classified into three levels: sufficient, moderate, and deficient. For soil samples with moderate nutrient levels in low-salinity areas, nitrogen and phosphorus nutrients were relatively insufficient, and the nutrient activation function of the bacterial community was determined to be phosphorus solubilization and nitrogen fixation. For soil samples with deficient nutrients in moderate-salinity areas, in addition to phosphorus solubilization and nitrogen fixation, the function of organic matter decomposition also needed to be enhanced, and the nutrient activation function of the bacterial community was determined to be phosphorus solubilization and nitrogen fixation + organic matter decomposition, thus clarifying the functional requirements of the bacterial community. For the function of phosphorus solubilization and nitrogen fixation, phosphate-solubilizing strains were screened using Monkina medium, and nitrogen-fixing strains were screened using Ashube medium. For the function of organic matter decomposition, cellulose-decomposing strains were screened using a screening medium with cellulose as the sole carbon source. During the screening process, soil samples were diluted and spread onto the medium, and cultured for 3-5 days at 28℃ with a salinity consistent with the corresponding salinity of the soil in the saline-alkali area. For example, when isolating phosphate-solubilizing bacteria from the low-salinity area of ​​Nandagang, Huanghua, the salt content of the culture medium was set to 3.5 g / kg, resulting in the isolation of phosphate-solubilizing Bacillus with a phosphate-solubilizing capacity of 17.6 mg / L. When isolating nitrogen-fixing bacteria from the medium-salinity area, the salt content of the culture medium was set to 7.8 g / kg, resulting in the isolation of nitrogen-fixing Agrobacterium tumefaciens with a nitrogenase activity of 161.29 nmol C2H4 mL. 1 h -1 Single colonies growing on the culture medium were selected, purified, and cultured to obtain salt-tolerant microbial strains. The strains were preliminarily identified through morphological observation and physiological and biochemical tests, such as Bacillus, Trichoderma, and Aspergillus niger. Among them, Trichoderma and Aspergillus niger can secrete citric acid to neutralize soil alkalinity, which is suitable for the alkalinity reduction needs of medium-salt-alkali areas.

[0051] In this embodiment of the invention, the compatibility verification before mixing the salt-tolerant microbial strain includes:

[0052] The community structure of the salt-tolerant microbial strains was analyzed using omics analysis and quantitative real-time PCR, and the relative abundance of each strain in the salt-tolerant microbial strains was determined based on the community structure.

[0053] The effect of cascaded bacteria in the salt-tolerant microbial strains on soil nitrogen enhancement was quantified by gas chromatography, and the cascade synergistic effect among different strains was verified based on the enhancement effect and the relative abundance.

[0054] If the cascade synergistic effect does not meet the preset standard, adjust the inoculation ratio of each strain and return to the step of using omics analysis to analyze the community structure of the salt-tolerant microbial strain until the cascade synergistic effect meets the preset standard.

[0055] For salt-tolerant microbial strains whose cascade synergistic effect meets the preset standard, the chemical composition of the metabolites of the salt-tolerant microbial strains that meet the preset standard is analyzed by nuclear magnetic resonance, and the active components related to soil nutrient activation in the metabolites are determined based on the chemical composition.

[0056] The types and contents of small molecule organic matter produced by the salt-tolerant microbial strains that meet the preset standards after decomposing soil organic matter are analyzed, and the soil fertility characteristics of the salt-tolerant microbial strains are analyzed based on the active ingredients and the types and contents of the small molecule organic matter.

[0057] Salt-tolerant microbial strains that meet the cascade synergistic effect and possess excellent soil characteristics are considered as qualified microbial strains for compatibility verification.

[0058] In detail, the omics analysis employed high-throughput sequencing technology to extract total DNA from salt-tolerant microbial strains, construct sequencing libraries, and perform sequencing using a high-throughput sequencing platform to obtain the strains' gene sequence data. Bioinformatics software was used to analyze the gene sequence data, identify the species classification information of each strain, construct community structure maps, determine the relative abundance of each strain in the community, and analyze the absolute abundance of functional bacterial groups using quantitative real-time PCR. Salt-tolerant microbial strains were added to saline-alkali soil and cultured in serum bottles for a period of time. The effect of cascade bacteria (such as nitrogen-fixing bacteria) on soil nitrogen enhancement was then detected using the acetylene reduction method. For example, *Azospirillum azotoxinus* in the low-salt-alkali area of ​​Huanghua Nandagang increased the autotrophic nitrogen fixation capacity of saline-alkali soil by 11%. *Bacillus phosphate-solubilizing* utilized ammonia nitrogen for growth and reproduction, while simultaneously releasing phosphatases to decompose insoluble phosphorus in the soil, increasing phosphorus activation by 35% compared to single-strain culture. *Trichoderma* decomposed organic phosphorus into inorganic phosphorus, forming a cascade pathway for nitrogen and phosphorus nutrient transformation. By analyzing the relative abundance of each strain, the integrity and efficiency of the cascade pathway were assessed. If the soil nitrogen fixation efficiency increased by more than 10% and the phosphorus activation increased by more than 30% compared to the single-strain culture, the cascade synergistic effect was considered to have met the preset standard. If the cascade synergistic effect did not meet the standard, for example, a group of strains in the Huanghua Nandagang medium-saline-alkali area showed a soil nitrogen fixation efficiency of 5% and a phosphorus activation increase of 15%, the inoculation ratio was adjusted according to the functional contribution of each strain. The inoculation ratio of nitrogen-fixing Agrobacterium tumefaciens was increased from 30% to 45%, while the inoculation ratio of Aspergillus niger was decreased from 40% to 15%, while the inoculation ratio of salt-tolerant cellulose-decomposing bacteria remained unchanged. After adjustment, the co-culture was repeated to further verify the cascade synergistic effect. This process was repeated until the cascade synergistic effect met the preset standard. By dynamically adjusting the inoculation ratio, the optimal synergistic effect among the strains was ensured. Metabolites of salt-tolerant microbial strains meeting pre-defined criteria were detected using nuclear magnetic resonance spectroscopy. By analyzing characteristics such as chemical shifts and peak shapes in the spectra, the chemical composition of the metabolites, including organic acids, amino acids, and enzymes, was determined. For example, the metabolites of a strain from the saline-alkali area of ​​Huanghua Nandagang were found to contain organic acids such as oxalic acid and formic acid, with oxalic acid at a concentration of 1.9 mg / ml and formic acid at a concentration of 9.3 mg / ml. Organic acids can dissolve insoluble phosphorus in the soil and neutralize soil alkalinity; these components are all active ingredients related to soil nutrient activation.

[0059] Specifically, the soil-enhancing characteristics of the strains were analyzed: organic acids and phosphatases, among other active components, synergistically enhance the availability of soil nutrients; small-molecule organic matter such as glucose and amino acids provides carbon and nitrogen sources for soil microorganisms, promoting soil microbial diversity; simultaneously, small-molecule organic matter improves soil particle structure and enhances soil water and fertilizer retention capacity. Referring to the experimental results from the Cangzhou Nandagang Experimental Station, the soil nitrogen fixation capacity and available phosphorus content significantly improved after treatment with these strains, both exceeding the control treatment, indicating excellent soil-enhancing characteristics. Considering both the cascade synergistic effect and the soil-enhancing characteristics evaluation results, only salt-tolerant microbial strains that simultaneously meet the preset standards for cascade synergistic effect and possess excellent soil-enhancing characteristics can be considered as qualified microbial strains for compatibility verification and proceed to subsequent compound culture steps. For example, a group of salt-tolerant microbial strains in the Huanghua Nandagang medium-saline-alkali area showed a 10% increase in soil nitrogen fixation capacity, a 40% increase in phosphorus activation, abundant active components in metabolites, a 45% proportion of beneficial components in small-molecule organic matter, and a significant increase in soil enzyme activity after treatment, thus qualifying for qualified compatibility verification.

[0060] In this embodiment of the invention, the soil organic matter content of different types of saline-alkali areas was detected by potassium dichromate oxidation-external heating method. For example, the average organic matter content of the soil in the low-salinity saline-alkali area of ​​Huanghua Nandagang was 6.5 g / kg, and the average organic matter content in the medium-salinity saline-alkali area was 6.0 g / kg. Referring to the standard organic matter content of healthy farmland soil (20-30 g / kg), the carbon source supplementation requirement of the low-salinity saline-alkali area was determined to be medium, and the carbon source supplementation requirement of the medium-salinity saline-alkali area was determined to be high. The organic matter composition of the natural system soil in different types of saline-alkali areas was detected by elemental analysis, which showed that it was mainly composed of cellulose, hemicellulose, lignin, etc. Therefore, decomposed straw (rich in cellulose and hemicellulose) and agricultural waste fermentation substrate (such as fermented food waste products, rich in humus) were selected as basic raw materials. In the low-salinity saline-alkali area, a mixture of decomposed straw and agricultural waste fermentation substrate was used, while the proportion of agricultural waste fermentation substrate was increased in the medium-salinity saline-alkali area to adapt to the carbon source supplementation requirement and organic matter composition.

[0061] Specifically, the ratio of basic raw materials is determined based on carbon source replenishment needs. For example, in the low-salinity area of ​​Huanghua Nandagang, where carbon source replenishment needs are moderate, the ratio of decomposed straw to agricultural waste fermentation substrate is 6:4; in the medium-salinity area, where carbon source replenishment needs are higher, the ratio is 4:6. The proportioned basic raw materials are then placed in a fermentation tank, and a microbial composting accelerator (made from previously screened soil bacteria) is added. The fermentation temperature is controlled at 55-60℃, and the humidity at 60-65%. Regular turning and aeration are ensured to guarantee smooth aerobic fermentation. During fermentation, the strains in the microbial composting accelerator decompose large-molecule organic matter in the basic raw materials, converting it into small-molecule humic substances, amino acids, and other nutrients easily absorbed by crops. The fermentation time is 20-30 days. Fermentation is complete when the temperature of the fermentation pile stabilizes at room temperature and no odor is produced, yielding the initial organic products. For example, the initial organic matter content of the initial organic products in the low-salinity area is 45%, and in the medium-salinity area, it is 50%, both providing sufficient carbon source replenishment for the soil.

[0062] Furthermore, acidic fermentation products from agricultural waste (such as citrus peel fermentation broth, with a pH of 3.0-4.0) were used to adjust the initial organic matter to acidity. The pH of the organic matter was monitored in real time during the adjustment process. For example, the average pH of the soil in the low-salt-alkali area of ​​Huanghua Nandagang was 7.5, so the pH of the initial organic matter was adjusted to 6.0-6.5; the average pH of the soil in the medium-salt-alkali area was 7.52, so the pH of the initial organic matter was adjusted to 5.5-6.0 to meet the requirements for reducing alkalinity in saline-alkali land. After adjustment, the nutrient content of the organic matter was tested. The Kjeldahl method was used to determine the total nitrogen content, the molybdenum-antimony colorimetric method was used to determine the total phosphorus content, and the flame photometry method was used to determine the total potassium content, ensuring that the total nitrogen content was ≥2%, the total phosphorus content was ≥1%, the total potassium content was ≥1.5%, and the organic matter content was ≥40%. After passing the tests, the bio-organic products are obtained. These products can replenish soil carbon sources and nutrients, and also help reduce soil alkalinity. For example, in moderately saline-alkali areas, the application of bio-organic products can reduce the soil pH by 0.2-0.5 units. This step, through acidity adjustment and nutrient testing, ensures the quality and improvement effect of the bio-organic products.

[0063] Furthermore, functional microbial communities and bio-organic products tailored to different types of saline-alkali areas have been developed. Both possess functions such as nutrient activation and salinity mitigation, but their effectiveness is limited when used alone. Scientifically mixing the functional microbial communities and bio-organic products can achieve synergistic effects. The bio-organic products provide the microbial communities with carbon sources and carriers for growth and reproduction, while the microbial communities promote the release of nutrients from the organic products. Therefore, the two need to be mixed in a specific mass ratio to obtain a specialized microbial soil conditioner.

[0064] S3. Mix the functional microbial community and the biological organic products in a certain mass ratio to obtain a microbial soil conditioner for the different types of saline-alkali areas.

[0065] In this embodiment of the invention, the microbial soil conditioner refers to a special improvement product made of mixed materials that can synergistically improve the condition of saline-alkali soil.

[0066] In this embodiment of the invention, the step of mixing the functional microbial community and the biological organic product in a specific mass ratio to obtain a microbial soil conditioner for the different types of saline-alkali areas includes:

[0067] Analyze the mixed mass ratio of the functional microbial community and the biological organic products;

[0068] The functional microbial community and the biological organic products are mixed evenly according to the specified mixing mass ratio;

[0069] Based on the optimized fermentation system of multiple functional species, the optimized fermentation conditions for different types of saline-alkali areas are determined, and the mixing parameters in the uniform mixing process are optimized using the optimized fermentation conditions to obtain the mixed material.

[0070] Microbial soil conditioners for different types of saline-alkali areas are generated based on the mixture.

[0071] In detail, determining the mixing mass ratio requires comprehensive consideration of the activity of functional microbial communities, the nutrient content of bio-organic products, and the performance of the carrier. The viable count of functional microbial communities is determined using the plate count method; for example, the viable count of functional microbial communities in the Huanghua Nandagang low-salt-alkali area is 10. 7 CFU / g, viable count of functional microbial flora in the medium-saline-alkali area is 10. 6 CFU / g. The organic matter and humic content of the bio-organic products were determined using relevant detection methods. For example, the organic matter content of the bio-organic products in low-salinity areas was 45%, and in medium-salinity areas it was 50%. Referring to the commonly used ratio range of microorganisms and organic products in saline-alkali land improvement, and combined with the functional requirements of this invention, the mixing mass ratio of functional microbial communities to bio-organic products in the low-salinity area of ​​Huanghua Nandagang was determined to be 3:7, and in the medium-salinity area it was 4:6. This ratio ensures both the effective concentration of the microbial community and allows the bio-organic products to fully play their role as carriers and nutrient suppliers.

[0072] Specifically, the bio-organic products are placed in a mixer, and the mixer is turned on for pre-stirring at a speed of 30-50 rpm for 5-10 minutes to ensure uniform texture of the organic products. The functional microbial community is then slowly added to the mixer according to the determined mixing mass ratio. For example, in the low-salinity area of ​​Huanghua Nandagang, 3 kg of functional microbial community and 97 kg of bio-organic products are added; in the medium-salinity area, 4 kg of functional microbial community and 96 kg of bio-organic products are added. The mixer speed is adjusted to 60-80 rpm, and the mixing time is 15-20 minutes. During the mixing process, samples are taken periodically to test the uniformity of the mixture. Uniformity is determined by the coefficient of variation (COP) of the viable bacteria count in the samples. If the COP is below 10%, the mixture is considered uniform. For example, in the low-salinity area, the viable bacteria count at different sampling points in the mixture was all above 0.9 × 10⁻⁶. 8 -1.1×10 8 The coefficient of variation was 8% between CFU / g, which met the uniformity requirements and ensured that the microbial community was evenly distributed in the organic product, thus solving the problem of excessively high or low local microbial community concentration caused by uneven mixing.

[0073] Furthermore, the optimized fermentation system for multiple functional species was established based on previous strain culture experiments, including suitable ranges for key parameters such as temperature, pH, and dissolved oxygen. For example, in the optimized fermentation system for functional microbial communities in the low-salt-alkali area of ​​Huanghua Nandagang, the temperature range was 25-28℃ and the pH range was 6.5-7.0; in the optimized fermentation system for the medium-salt-alkali area, the temperature range was 28-30℃ and the pH range was 6.0-6.5. Based on the optimized fermentation conditions, the mixing parameters were further optimized: if the temperature of the mixture exceeded the suitable temperature range of the fermentation system during mixing, the mixer speed was reduced and the mixing time was extended; if the pH of the mixture deviated from the suitable range, it was fine-tuned by adding a small amount of acidic or alkaline regulator. For example, during the mixing process in the medium-salt-alkali area, the temperature of the mixture was detected to be 31℃, exceeding the suitable range. The mixer speed was reduced from 80 rpm to 60 rpm, and the mixing time was extended from 15 minutes to 20 minutes, reducing the temperature to 29℃. The optimized mixture ensures the activity of the microbial community while also strengthening the bond between organic products and the microbial community. The mixture is dried using a low-temperature drying method, with the temperature controlled at 35-40℃ to avoid inactivating the microbial community due to high temperatures, until the moisture content is 15-20%. After drying, the mixture is pulverized and passed through a 2 mm sieve to ensure uniform particle size for easy application. The pulverized microbial soil conditioner undergoes quality testing, including indicators such as viable cell count, organic matter content, and pH value. For example, the viable cell count of the microbial soil conditioner in the Huanghua Nandagang low-salt-alkali area is ≥10. 8 CFU / g, organic matter content ≥35%, pH value 6.5-7.0; viable bacteria count of microbial soil conditioner in medium-saline-alkali areas ≥10.9 The soil conditioner has the following parameters: CFU / g, organic matter content ≥40%, and pH value 6.0-6.5. After passing the tests, specialized microbial soil conditioners for different types of saline-alkali areas were obtained. The microbial soil conditioner for low-salinity areas focuses on phosphorus solubilization and nitrogen fixation, while the microbial soil conditioner for medium-salinity areas focuses on the synergistic function of salt tolerance, alkali reduction, and nutrient activation. Referring to the experimental results from the Cangzhou Nandagang Experimental Station, the wheat seedling growth after application of this type of microbial soil conditioner was significantly better than other treatments. For example, the T3 treatment showed the best performance, with a fresh weight of 263.84g and a dry weight of 98.62g.

[0074] Furthermore, the soil structure in heavy clay areas of saline-alkali land is compact, with poor aeration and permeability. For example, in some areas of the Huanghua Nandagang Demonstration Zone, the soil clay content is high, making it difficult for soil conditioners to fully contact the soil when applied directly, thus affecting the improvement effect. Therefore, it is necessary to first identify the heavy clay areas in the target saline-alkali land and carry out deep stratification treatment to improve the soil structure and form a loose topsoil layer, creating conditions for the subsequent application and effectiveness of soil conditioners.

[0075] S4. Identify the heavy clay texture area in the target saline-alkali land, perform deep stratification on the heavy clay texture area, and obtain the loose topsoil layer of the target saline-alkali land.

[0076] In this embodiment of the invention, the heavy clay texture area refers to the area where the soil has a high clay content, compact structure, and poor aeration and permeability, such as the area where the soil clay content is ≥30% and the compactness is ≥1500 kPa in some areas of Huanghua Nandagang Demonstration Zone.

[0077] In this embodiment of the invention, identifying the heavy clay texture area in the target saline-alkali land includes:

[0078] The clay content and soil compaction of each sampling point were tested;

[0079] When the clay content of the farmland soil in the target saline-alkali land is greater than that of the natural soil and the soil structure compaction of the farmland soil is greater than that of the natural soil, it is marked as a potential clay-heavy texture area.

[0080] Soil profile analysis was performed on the potential heavy clay area to obtain data on the thickness of the compaction layer;

[0081] The threshold for determining the heavy clay texture region is determined based on the clay content, the structural compactness, and the thickness of the compacted layer.

[0082] Based on the aforementioned judgment threshold, each region of the target saline-alkali land is judged one by one to obtain the heavy clay texture region.

[0083] In detail, the clay content was determined using a hydrometer method. Soil samples were dispersed and placed in a hydrometer, and the clay content was calculated based on the hydrometer readings at different time points. For example, the clay content of a soil sample from a sampling point in the Huanghua Nandagang Demonstration Area was 35%. The structural compaction was determined using a soil compaction meter. The probe of the compaction meter was inserted into the soil, and the resistance value during insertion was recorded. The structural compaction was expressed in kilopascals (kPa). For example, the structural compaction of the soil at this sampling point was 1800 kPa. During the testing process, each sampling point was tested in three layers (0-15cm, 15-30cm, and 30-40cm) within the 0-40cm soil layer, and the average value was taken as the clay content and structural compaction data for that sampling point. For example, at sampling point L2 in the low-salinity alkali area of ​​Huanghua Nandagang, the clay content was 29% and the compactness was 118.9 kPa; at sampling point M2 in the medium-salinity alkali area, the clay content was 49% and the compactness was 356.0 kPa. Comparing the clay content and compactness data of farmland soil and natural soil within the same study unit, the farmland soil had a higher clay content and compactness than the natural soil. This indicates that the farmland soil has clay aggregation and compactness due to improper human cultivation, etc. Therefore, this area is marked as a potential heavy clay soil area.

[0084] Specifically, soil profile pits were excavated in potentially heavy clay areas to a depth of 60 cm. The layered structure of the soil profile was analyzed to identify the compacted layer (a layer where the soil color darkens, the structure becomes denser, and roots have difficulty penetrating). The vertical thickness of the compacted layer was measured using a measuring tape. For example, in one potentially heavy clay area in Huanghua's Nandagang district, the compacted layer was located in the 15-30 cm soil layer, with a thickness of 15 cm; in another potential area, the compacted layer was located in the 20-40 cm soil layer, with a thickness of 20 cm. Simultaneously, soil samples from the compacted layer were collected for clay content and compaction testing to verify the texture characteristics of the compacted layer. For example, the clay content of the compacted soil was 38%, and the compaction was 1900 kPa, further confirming its heavy clay nature. Data on clay content, compaction, and compacted layer thickness were collected from all potentially heavy clay areas, and statistical analysis methods were used to determine the judgment threshold. Based on the soil conditions of the Huanghua Nandagang Demonstration Area, a combination of clay content ≥30%, soil compaction ≥1500 kPa, and compaction layer thickness ≥10 cm was determined as the judgment threshold. If the soil parameters of a certain area simultaneously meet these three conditions, it is judged as a heavy clay soil area. This judgment threshold comprehensively considers the soil particle composition, soil compaction, and layer characteristics to ensure the scientific validity and accuracy of the judgment results.

[0085] Furthermore, the target saline-alkali land was divided into several 10m × 10m evaluation units, each corresponding to the detection data of one or more sampling points. Each evaluation unit was judged individually according to the judgment threshold. If the clay content of an evaluation unit was ≥30%, the structural compactness was ≥1500 kPa, and the thickness of the compacted layer was ≥10 cm, then the evaluation unit was judged as a heavy clay land area. For example, in the Huanghua Nandagang Demonstration Area, one evaluation unit had a clay content of 33%, a structural compactness of 1650 kPa, and a compacted layer thickness of 12 cm, meeting the judgment threshold and was judged as a heavy clay land area. Another evaluation unit had a clay content of 28%, and although the structural compactness and compacted layer thickness met the standards, the clay content did not meet the threshold and was not judged as a heavy clay land area. Through individual judgments, the distribution range of heavy clay land areas in the target saline-alkali land was finally determined, ensuring the comprehensiveness and accuracy of heavy clay land area identification.

[0086] In this embodiment of the invention, the loose tillage layer refers to the soil tillage layer formed by uniformly mixing the various loose soil layers, which is suitable for crop growth and allows the soil conditioner to function effectively.

[0087] In this embodiment of the invention, the deep stratification treatment of the heavy clay region to obtain a loose topsoil layer for the target saline-alkali land includes:

[0088] The processing depth is divided into different levels based on the thickness of the hardened layer in the viscous region.

[0089] The viscous and heavy texture region is divided into different layers based on different depths;

[0090] Deep loosening and deep turning of the different layer areas are carried out to obtain the loose soil layer areas corresponding to the different layer areas;

[0091] Deep loosening and deep plowing are carried out on the loose soil layers corresponding to different layers to obtain the loose topsoil layer of the target saline-alkali land.

[0092] In detail, based on the thickness and distribution of the compacted layer, the treatment depth is divided into three layers: surface, middle, and deep. For example, in the Huanghua Nandagang heavy clay area, when the compacted layer thickness is 10-15cm and located within the 15-30cm soil layer, the surface depth is 0-15cm, the middle depth is 15-30cm (the layer containing the compacted layer), and the deep depth is 30-40cm; when the compacted layer thickness is 15-20cm and located within the 20-40cm soil layer, the surface depth is 0-20cm, the middle depth is 20-40cm (the layer containing the compacted layer), and the deep depth is 40-60cm. The depth division of different layers matches the distribution of the compacted layer, ensuring that subsequent soil loosening treatment can accurately target the compacted layer. According to the defined surface, middle, and deep depth ranges, each heavy clay area is divided into three independent layer regions: the surface region, the middle region (compacted layer region), and the deep region. For example, in a heavy clay soil area in Nandagang, Huanghua, the surface layer is 0-15cm, the middle layer is 15-30cm, and the deep layer is 30-40cm; these layers are spatially continuous and together constitute a complete heavy clay soil area. This step, by clearly defining the different layers, provides a basis for subsequent differentiated soil loosening treatment.

[0093] Specifically, a rotary tiller is used for light harrowing and loosening of the soil. The tilling depth of the rotary tiller is adjusted to the depth of the surface area, and the spacing between the harrow teeth is set to 5-8 cm. The rotation of the harrow teeth cuts and breaks up the compacted structure of the surface soil, making the surface soil loose and creating a loose surface soil layer. For the middle layer (compacted layer), a moldboard plow is used for deep tilling and loosening of the soil. The depth of the plowshare is adjusted to the depth of the middle layer, turning over the compacted soil, breaking up the agglomeration network of soil clay particles, and simultaneously turning over some of the loose soil from the lower layer to the middle layer, creating a loose middle layer soil layer. For the deep layer, a deep loosening shovel is used for targeted loosening of the soil. The depth of the deep loosening shovel is adjusted to the depth of the deep layer, loosening only the severely compacted areas in the deep soil, opening up the aeration pores of the deep soil, and avoiding excessive disturbance that could damage the soil structure, resulting in a loose deep soil layer. For example, in the heavy clay soil area of ​​Huanghua Nandagang, after rotary tillage, the soil bulk density of the surface layer decreased from 1.5 g / cm³ to 1.2 g / cm³; after deep plowing, the compacted structure of the middle layer was completely broken up, and the soil aeration porosity increased by 40%; after targeted loosening treatment, the number of aeration pores in the deep layer increased significantly, and combined with concentrated summer rainfall, the EC value of the 0-100cm soil decreased by 30%-59.4%. A harrow was used to mix the surface, middle, and deep loose soil layers, with the harrow speed controlled at 40-60 rpm and the harrowing frequency controlled at 2-3 times to ensure thorough mixing of each layer. During mixing, the soil particle uniformity and aeration porosity were tested; mixing was stopped when the soil particle uniformity reached over 85% and the aeration porosity reached 15-20%. The resulting loose topsoil layer, 30-40cm thick, features a loose soil structure with good aeration and water permeability, creating favorable conditions for crop root growth and nutrient release from microbial soil conditioners. For example, in the heavy clay soil area of ​​Huanghua Nandagang, after treatment, the soil bulk density of the loose topsoil layer was 1.1-1.2g / cm³, and the aeration porosity was 18%, meeting the standards for an excellent topsoil layer. Furthermore, the salt leaching effect was significant after summer rainfall, increasing the water content of the 0-60cm soil layer and leaching salts to below 1m. By uniformly mixing the loose soil layers, a structurally stable loose topsoil layer was formed.

[0094] Furthermore, deep stratification treatment was completed in the heavy clay soil area, forming a loose topsoil layer with significantly improved soil structure. At this point, a specialized microbial soil conditioner was evenly applied to the loose topsoil layer to ensure full contact between the conditioner and the loose soil, allowing the microbial community to activate nutrients and alleviate salinity, thus forming an improved layer. The improved layer was then further cultivated to optimize soil structure, ensure stable improvement effects, and prepare for crop planting.

[0095] S5. Apply the microbial soil conditioner evenly to the loose topsoil layer to obtain the improved layer of the target saline-alkali land, and then perform tillage treatment on the improved layer.

[0096] In this embodiment of the invention, the improved layer refers to the soil layer that, after the application of the soil conditioner and allowing it to stand, exhibits reduced soil salinity, increased nutrient levels, and improved microbial community.

[0097] In this embodiment of the invention, the step of uniformly applying the microbial soil conditioner to the loose topsoil to obtain an improved layer for the target saline-alkali land includes:

[0098] The loose topsoil layer is leveled, and the amount of soil conditioner to be applied to the soil area is calculated based on the soil volume per unit area of ​​the leveled loose topsoil layer and the appropriate dosage of microbial soil conditioner.

[0099] According to the cultivation direction of the target saline-alkali land and the amount of the amendment applied, the soil area is applied in strips, and broadcasting is carried out between the strip applications;

[0100] Soil covering treatment is carried out on the soil area after the amendment is applied, and the soil area after soil covering treatment is left to stand for a preset time to obtain the improved layer of the target saline-alkali land.

[0101] In detail, a laser leveling instrument is used to level the loose topsoil layer, adjusting the soil surface slope to no more than 3° to eliminate unevenness and ensure uniform application of subsequent soil amendments. The soil bulk density and topsoil thickness are measured to calculate the soil volume per unit area. For example, in the Huanghua Nandagang Demonstration Area, the soil bulk density of the loose topsoil layer is 1.2 g / cm³, and the topsoil thickness is 30 cm, so the soil volume per unit area (1 square meter) is 360 kg. According to the appropriate dosage standards for different types of saline-alkali areas, the appropriate dosage standard for low-salinity areas is 0.5-0.8% of the soil volume per unit area, and for moderately saline-alkali areas it is 0.8-1.2%. For example, in a low-salinity saline-alkali area of ​​Huanghua Nandagang, the soil volume per unit area is 360 kg, and the soil amendment application rate is calculated to be 360 ​​× 0.6% = 2.16 kg / m². In a medium-salinity saline-alkali area, the soil volume per unit area is 360 kg, and the soil amendment application rate is calculated to be 360 ​​× 1.0% = 3.6 kg / m². Through leveling and precise calculation, the rationality and uniformity of the soil amendment application rate are ensured. The tillage direction is determined based on the topography of the target saline-alkali land and subsequent planting plans. For example, the tillage direction is along the long side of the topography in the Huanghua Nandagang demonstration area. Following the tillage direction, shallow trenches with a depth of 5-8 cm and a spacing of 20-30 cm are dug using a trenching machine. 70% of the calculated soil amendment application rate is evenly applied into the shallow trenches to complete the strip application operation. For example, in a certain soil area of ​​the low-salinity and alkaline zone in Huanghua's Nandagang area, the application rate of soil conditioner was 2.16 kg / m², with a strip application rate of 1.512 kg / m²; in a certain area of ​​the medium-salinity and alkaline zone, the application rate was 3.6 kg / m², with a strip application rate of 2.52 kg / m². In the shallow furrows after strip application, a fertilizer spreader was used to evenly spread the remaining 30% of the conditioner onto the soil surface, completing the spreading operation. During spreading, the speed and output of the fertilizer spreader were controlled to ensure uniform application. This combination of strip and spreader application ensured both deep distribution of the conditioner in the soil and uniform coverage of the conditioner in the surface soil.

[0102] Specifically, a rotary tiller is used to shallowly till and cover the soil area after the soil conditioner has been applied. The tillage depth is controlled at 10-15 cm to ensure that the conditioner applied in shallow furrows and spread on the surface is thoroughly mixed with the soil. After shallow tillage, a set resting period of 3-5 days is allowed, during which the soil moisture is maintained at 60-70% (field holding capacity) to provide a suitable growth and reproduction environment for the functional microbial community in the conditioner. During the resting period, the microbial community gradually colonizes the soil, producing active ingredients such as organic acids and enzymes, neutralizing soil alkalinity and activating soil nutrients; the bio-organic products slowly release nutrients, providing nutrition for the microbial community and crops. After the resting period, the soil pH value decreases, the salinity content decreases, and the nutrient availability increases, forming an improved layer for the target saline-alkali land. For example, in the low-salinity zone of Huanghua Nandagang, the pH value of the improved layer decreased from 7.5 to 7.0, the salt content decreased from 2.9 g / kg to 2.5 g / kg, and the available phosphorus content increased from 8.13 mg / kg to 12 mg / kg; in the medium-salinity zone, the pH value of the improved layer decreased from 8.0 to 7.3, the salt content decreased from 5.8 g / kg to 3.5 g / kg, and the available phosphorus content increased from 7.87 mg / kg to 10 mg / kg.

[0103] Further, the uniformity of soil particles and the aeration porosity of the improved layer were tested to determine the intensity standard of the tillage treatment. A soil particle size analyzer was used to test particle uniformity, and a ring cutter method was used to test aeration porosity. If the particle uniformity was below 85% and the aeration porosity was below 15%, the tillage intensity needed to be increased; if the standard was met, conventional tillage intensity was used. A combined tillage machine was used to cross-till the improved layer, first along the long side of the terrain, and then along the short side, with a tillage depth controlled at 20-30 cm to ensure thorough breaking up and uniform mixing of soil particles. During tillage, the soil particle size was monitored in real time using a soil particle size analyzer. If large particles larger than 10 mm were found, the secondary breaking function of the combined tillage machine was activated to specifically break up the large particles. After tillage, a leveling machine was used to level the surface of the improved layer, eliminating furrow differences created by tillage and ensuring the surface flatness met crop sowing requirements (surface slope not exceeding 2°). After leveling, the soil is left to stand for 1-2 days to allow the improved soil particles to settle and stabilize naturally. This also promotes the colonization of functional microorganisms in the soil pores, forming a moderately loose tillage structure and achieving integrated soil improvement. For example, in the Huanghua Nandagang demonstration area, after tillage treatment, the soil particle uniformity of the improved layer reached 90%, the aeration porosity reached 18%, and the soil bulk density was 1.15 g / cm³, fully meeting the standards for an excellent tillage layer. After planting crops, wheat yields in low-salinity areas can reach over 400 jin per mu, and corn yields can reach over 850 jin per mu; in moderately saline-alkali areas, wheat yields can reach over 340 jin per mu, and corn yields can reach over 650 jin per mu, significantly higher than in unimproved areas. Through meticulous tillage treatment, the soil structure of the improved layer has been further optimized, ensuring stable and lasting improvement results.

[0104] like Figure 2 The diagram shown is a functional block diagram of an integrated microbial improvement and cultivation system for saline-alkali land provided in an embodiment of the present invention.

[0105] The integrated microbial improvement and cultivation system 100 for saline-alkali land described in this invention can be installed in an electronic device. Depending on the functions implemented, the integrated microbial improvement and cultivation system 100 for saline-alkali land may include a saline-alkali zone delineation module 101, a functional microbial community screening and generation module 102, a microbial soil conditioner generation module 103, a deep stratification treatment module 104, and a cultivation treatment module 105. The module described in this invention can also be called a unit, which refers to a series of computer program segments that can be executed by the processor of an electronic device and can perform a fixed function, stored in the memory of the electronic device.

[0106] In this embodiment, the functions of each module / unit are as follows:

[0107] The saline-alkali area division module 101 is used to perform multi-point sampling and detection on the target saline-alkali land, obtain the soil salinity content at each sampling point, and divide the target saline-alkali land into different types of saline-alkali areas based on the soil salinity content.

[0108] The functional microbial community screening and generation module 102 is used to screen and generate functional microbial communities and biological organic products for different types of saline-alkali areas based on the soil nutrient parameters of the target saline-alkali land.

[0109] The microbial soil conditioner generation module 103 is used to mix the functional microbial community and the biological organic products in a mass ratio to obtain a microbial soil conditioner for the different types of saline-alkali areas.

[0110] The deep stratification processing module 104 is used to identify the heavy clay texture area in the target saline-alkali land, perform deep stratification processing on the heavy clay texture area, and obtain the loose topsoil layer of the target saline-alkali land.

[0111] The tillage treatment module 105 is used to uniformly apply the microbial soil conditioner to the loose tillage layer to obtain an improved layer of the target saline-alkali land, and to perform tillage treatment on the improved layer.

[0112] In detail, the modules described in the integrated microbial improvement and cultivation system 100 for saline-alkali land in this embodiment of the invention adopt the same usage as described above. Figure 1 The same technical means and the same technical effects as the microbial improvement and integrated farming method for saline-alkali land described in the article will not be repeated here.

[0113] In the several embodiments provided by this invention, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the system embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and other division methods may be used in actual implementation.

[0114] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0115] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional modules.

[0116] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0117] Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects. The scope of the invention is not limited to the foregoing description, and all variations within the meaning and scope of equivalents falling within the protection scope are intended to be included in the invention.

[0118] The embodiments of this application can acquire and process relevant data based on artificial intelligence technology. Artificial intelligence (AI) refers to the theories, methods, technologies, and application systems that use digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to obtain optimal results.

[0119] Furthermore, it is clear that the word "including" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or systems described in a system item may also be implemented by a single unit or system through software or hardware. Terms such as "first," "second," etc., are used to indicate names and do not indicate any specific order.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for integrated microbial amelioration and tillage of saline and alkaline soils, characterized by, The method comprises: Multi-point sampling detection is performed on the target saline-alkali land to obtain the soil salt content of each sampling point, and the target saline-alkali land is divided into different types of saline-alkali zones based on the soil salt content; The nutrient level of the soil sample of the different types of saline-alkali zones is determined according to the soil nutrient parameters, and the nutrient activation function direction of the microbial flora is determined according to the nutrient level; the salt-tolerant microbial strains are separated from the soil sample according to the nutrient activation function direction; the compatibility of the salt-tolerant microbial strains before mixing is verified, and the salt-tolerant microbial strains that pass the compatibility verification are subjected to compound culture to obtain functional microbial flora for different types of saline-alkali zones; the biological organic carbon source supplement demand is determined based on the soil organic matter content parameters of different types of saline-alkali zones of the target saline-alkali land, and the basic raw material is selected based on the organic matter composition of the natural system soil of different types of saline-alkali zones; the ratio of the basic raw material is adjusted according to the carbon source supplement demand, and the basic raw material after ratio adjustment is subjected to aerobic fermentation treatment to obtain an initial organic product; the initial organic product is subjected to acid adjustment treatment, and the nutrient content of the adjusted organic product is detected to obtain a biological organic product, wherein the compatibility verification of the salt-tolerant microbial strains before mixing comprises: analyzing the community structure of the salt-tolerant microbial strains by using omics analysis and fluorescence quantitative PCR, and determining the relative abundance of each strain in the salt-tolerant microbial strains according to the community structure; the promotion effect of cascade bacteria in the salt-tolerant microbial strains on soil nitrogen is quantified by using gas chromatography, and the cascade synergistic effect between different strains is verified according to the promotion effect and the relative abundance; if the cascade synergistic effect does not meet the preset standard, the inoculation ratio of each strain is adjusted, and the step of analyzing the community structure of the salt-tolerant microbial strains by using omics analysis is returned to until the cascade synergistic effect meets the preset standard; for the salt-tolerant microbial strains with the cascade synergistic effect meeting the preset standard, the chemical composition of the metabolic products of the salt-tolerant microbial strains meeting the preset standard is analyzed by using nuclear magnetic resonance, the active ingredients related to soil nutrient activation in the metabolic products are determined according to the chemical composition; the types and contents of small molecule organic matters produced after the salt-tolerant microbial strains meeting the preset standard decompose soil organic matter are analyzed, and the soil improvement characteristics of the salt-tolerant microbial strains are analyzed according to the active ingredients and the types and contents of small molecule organic matters; the salt-tolerant microbial strains with the cascade synergistic effect meeting the standard and excellent soil improvement characteristics are used as the microbial strains that pass the compatibility verification; The functional microbial flora and the biological organic product are mixed in a mass ratio to obtain a microbial soil improver for different types of saline-alkali zones; Heavy clay areas in the target saline-alkali land are identified, and the heavy clay areas are subjected to deep layering treatment to obtain a loose cultivation layer of the target saline-alkali land; The microbial soil improver is uniformly applied to the loose cultivation layer to obtain an improved layer of the target saline-alkali land, and the improved layer is subjected to tillage treatment.

2. The method for microbial reclamation and integrated farming of saline and alkaline soils as claimed in claim 1, wherein, The target saline-alkali land is multi-point sampled and detected to obtain soil salt content of each sampling point, including: A representative research unit is selected in the range of the target saline-alkali land, wherein each research unit contains farmland system soil and natural system soil; Sampling points are arranged in the research unit according to a preset spatial grid distribution principle, and soil samples of each sampling point are collected; The soil samples are detected for salt content to obtain soil salt content of each sampling point.

3. The method for microbial reclamation and integrated farming of saline and alkaline soils as claimed in claim 1 wherein, The target saline-alkali land is divided into different types of saline-alkali regions based on the soil salt content, including: The soil salt content of each sampling point is compared with a preset soil salt content threshold range; Based on the comparison result and the biological diversity and functional dominant factor of the target saline-alkali land, the target saline-alkali land is divided into different types of regions; Spatial boundary information of the different types of regions is identified, and different types of regions are supplemented with sampling and detection according to the spatial boundary information to obtain different types of saline-alkali regions.

4. The method for microbial reclamation and integrated farming of saline and alkaline soils as claimed in claim 1 wherein, The functional microbial flora and the biological organic product are mixed in a quality ratio to obtain the microbial soil conditioner for different types of saline-alkali regions, including: The mixing quality ratio of the functional microbial flora and the biological organic product is analyzed; The functional microbial flora and the biological organic product are uniformly mixed according to the mixing quality ratio; Optimized fermentation conditions for different types of saline-alkali regions are determined according to a preset optimized fermentation system of multiple functional species, and the mixing parameters in the uniform mixing process are optimized by using the optimized fermentation conditions to obtain mixed materials; The microbial soil conditioner for different types of saline-alkali regions is generated according to the mixed materials.

5. The method for microbial reclamation and integrated farming of saline and alkaline soils as claimed in claim 1 wherein, The heavy clay region in the target saline-alkali land is identified, including: The clay content and structure tightness of the soil of each sampling point are detected; When the clay content of the farmland system soil in the target saline-alkali land is greater than that of the natural system soil, and the structure tightness of the farmland system soil is greater than that of the natural system soil, the region is marked as a potential heavy clay region; The potential heavy clay region is analyzed for soil profile to obtain data of the hardening layer thickness; A determination threshold of the heavy clay region is determined according to the clay content, the structure tightness and the data of the hardening layer thickness; Each region of the target saline-alkali land is determined one by one according to the determination threshold to obtain the heavy clay region.

6. The method for microbial reclamation and integrated farming of saline and alkaline soils as claimed in claim 1 wherein, The heavy clay region is processed by deep layering to obtain a loose cultivation layer of the target saline-alkali land, including: The processing depth is divided into different levels of depth based on the hardening layer thickness of the heavy clay region; The heavy clay region is divided into different layer regions according to the different levels of depth; The different layer regions are processed by deep scarification and deep ploughing to obtain loose soil layer regions corresponding to the different layer regions; The loose soil layer regions corresponding to the different layer regions are processed by deep scarification and deep ploughing to obtain the loose cultivation layer of the target saline-alkali land.

7. The method for microbial reclamation and integrated farming of saline and alkaline soils as claimed in claim 1 wherein, The microbial soil conditioner is uniformly applied to the loose cultivation layer to obtain an improved layer of the target saline-alkali land, including: The loose plough layer is flattened, and the soil area is calculated based on the unit area soil volume of the flattened loose plough layer and the adaptive amount standard of the microbial soil modifier to obtain the modifier application amount of the soil area; According to the plowing direction of the target saline-alkali soil and the modifier application amount, the soil area is strip applied, and the gap between the strip application is broadcast applied; The soil area after applying the modifier is soil covered, and the soil covered soil area is rested according to the preset resting time to obtain the improved layer of the target saline-alkali soil.

8. A microbial amendment and integrated farming system for saline and alkaline soils, characterized by, The system for performing the microbial improvement and integrated plowing method for saline-alkali soil as claimed in any one of claims 1-7, the system comprises: The saline-alkali area division module is used for multi-point sampling detection of the target saline-alkali soil to obtain the soil salt content of each sampling point, and the target saline-alkali soil is divided into different types of saline-alkali areas based on the soil salt content. The functional microbial flora screening generation module is configured to determine the nutrient level of the soil sample of different types of saline-alkali regions according to the soil nutrient parameters, determine the nutrient activation function direction of the flora according to the nutrient level, separate salt-tolerant microbial strains from the soil sample according to the nutrient activation function direction, verify the compatibility of the salt-tolerant microbial strains before mixing, and compound culture the salt-tolerant microbial strains that pass the compatibility verification to obtain the functional microbial flora for different types of saline-alkali regions; the biological organic carbon source supplement demand is determined based on the soil organic matter content parameters of different types of saline-alkali regions of the target saline-alkali soil, and the base raw material is selected based on the organic matter composition of the natural system soil of different types of saline-alkali regions; the ratio of the base raw material is adjusted according to the carbon source supplement demand, and the base raw material after the ratio adjustment is subjected to aerobic fermentation treatment to obtain an initial organic product; the initial organic product is subjected to acid adjustment treatment, and the nutrient content of the adjusted organic product is detected to obtain a biological organic product, wherein the compatibility verification of the salt-tolerant microbial strains before mixing includes: analyzing the community structure of the salt-tolerant microbial strains by using omics analysis and fluorescence quantitative PCR, and determining the relative abundance of each strain in the salt-tolerant microbial strains according to the community structure; the promotion effect of cascade bacteria in the salt-tolerant microbial strains on soil nitrogen is quantified by using gas chromatography, and the cascade synergistic effect between different strains is verified according to the promotion effect and the relative abundance; if the cascade synergistic effect does not reach the preset standard, the inoculation ratio of each strain is adjusted, and the step of analyzing the community structure of the salt-tolerant microbial strains by using omics analysis is returned to until the cascade synergistic effect meets the preset standard; the chemical composition of the metabolic products of the salt-tolerant microbial strains that meet the preset standard is analyzed by using nuclear magnetic resonance, the active ingredients related to soil nutrient activation in the metabolic products are determined according to the chemical composition, the types and contents of small-molecule organic matters produced after the salt-tolerant microbial strains that meet the preset standard decompose soil organic matter are analyzed, and the soil improvement characteristics of the salt-tolerant microbial strains are analyzed according to the active ingredients and the types and contents of small-molecule organic matters; the salt-tolerant microbial strains that meet the cascade synergistic effect and have excellent soil improvement characteristics are used as the microbial strains that pass the compatibility verification; The microbial soil conditioner generation module is configured to mix the functional microbial flora and the biological organic product at a mass ratio to obtain the microbial soil conditioner for different types of saline-alkali regions; The deep layering processing module is configured to identify a heavy clay region in the target saline-alkali soil, perform deep layering processing on the heavy clay region, and obtain a loose tillage layer of the target saline-alkali soil; The tillage processing module is configured to uniformly apply the microbial soil conditioner to the loose tillage layer to obtain an improved layer of the target saline-alkali soil, and perform tillage processing on the improved layer.

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