Urban green land soil improvement method based on green land carbon sink enhancement

Abstract

The invention discloses an urban green land soil improvement method based on green land carbon sink enhancement, and relates to the technical field of soil improvement, and the method comprises the following steps: carrying out soil quality diagnosis on soil of a target green land, preparing a functional soil matrix according to a diagnosis result, and carrying out soil replacement in a plant root zone; the method comprises the following steps: selecting plants with deep root systems and an efficient carbon sequestration function, constructing a three-dimensional community combining arbors, shrubs and herbaceous plants, and planting in a structured mode; aggregate forming bacteria, efficient carbon conversion bacteria and rhizosphere symbiotic growth-promoting bacteria are prepared into a compound microbial agent, and the compound microbial agent is inoculated to a root zone in a step-by-step targeted mode when plants are planted and after the plants are planted; a mineral stabilizer rich in multivalent metal ions is added into the soil, and an organic covering composed of different functional layers is laid on the surface layer; soil key indexes are monitored regularly, and a soil carbon sink system is maintained and managed. According to the invention, the improvement from single carbon sequestration to systematic ecological function improvement in soil improvement is realized.

Description

Technical Field

[0001] This invention relates to the field of soil improvement technology, and in particular to a method for improving urban green space soil based on enhancing carbon sequestration in green spaces. Background Technology

[0002] Currently, in the field of urban green space soil improvement and carbon sequestration enhancement, existing technologies mainly focus on the following aspects: First, existing technologies mostly enhance the carbon absorption capacity of green space ecosystems by increasing the biomass of trees, shrubs, or lawns, primarily relying on aboveground biomass and surface litter to increase soil organic carbon content. Second, some technologies improve soil fertility, promote nutrient cycling, or enhance aggregate structure stability by applying microbial agents to the soil, but their main objectives remain focused on nutrient regulation and improvement of soil physicochemical properties. Meanwhile, mulch materials (such as sawdust, bark, and straw) are typically used to suppress evaporation, reduce weeds, or improve soil moisture conditions, primarily belonging to physical regulation methods.

[0003] However, in existing plant-based carbon sequestration enhancement technologies, most green space plants are shallow-rooted herbaceous plants or shallow-rooted trees and shrubs, with their root systems mainly distributed in the topsoil. This results in carbon input being concentrated in the topsoil, and topsoil organic carbon is easily mineralized by temperature fluctuations, increased microbial activity, and human disturbance, making it difficult to form a long-term stable carbon storage structure. 4. There is a lack of technical means to effectively input carbon into deeper soil layers. Furthermore, existing microbial-related technologies primarily aim to improve soil fertility, promote nutrient release, or plant growth; microbial activity and plant root carbon input processes are independent and lack synergistic design. At the same time, under current technological conditions, even if soil organic carbon content is increased through fertilization, mulching, or increased organic matter input, the problem of "increased organic carbon input, but insufficient stability and low retention rate" still exists.

[0004] Existing technologies have not yet formed a comprehensive soil technology system with a clear structure, synergistic functions, and a focus on long-term carbon sequestration enhancement. Therefore, this invention proposes a method for improving urban green space soil based on enhancing green space carbon sequestration. Summary of the Invention

[0005] This invention provides a method for improving urban green space soil based on enhancing carbon sequestration in green spaces. It uses a synergistic planting method of deep roots, microorganisms, and mulch to solve the technical problem that there is no systematic technical system for the long-term carbon sequestration function of urban green space soil in the existing technology.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: This invention provides a method for improving urban green space soil based on enhancing green space carbon sequestration, comprising: S1. Conduct soil quality diagnosis on the target green space, prepare functional soil matrix based on the diagnosis results, and replace the soil in the root zone of the plants. S2, select plants with deep root systems and efficient carbon sequestration functions to construct a three-dimensional community combining trees, shrubs and herbs, and adopt a structured planting model; S3 is a compound microbial agent formulated with aggregate-forming bacteria, high-efficiency carbon-converting bacteria and rhizosphere symbiotic growth-promoting bacteria, which is then inoculated into the root zone in stages during and after plant planting. S4, add mineral stabilizers rich in polyvalent metal ions to the soil and lay an organic mulch composed of different functional layers on the surface; S5 involves regularly monitoring key soil indicators and implementing adaptive maintenance management of the soil carbon sequestration system based on the monitoring results.

[0007] The beneficial effects of the technical solution provided by this invention include at least the following: This scheme achieves a systematic enhancement of the carbon sequestration capacity of urban green space soil. By introducing organic carbon into the deep soil through deep-rooted plants, and utilizing the coupling effect of functional microorganisms and key mineral materials, active carbon is efficiently converted into a dual stable form protected by aggregate physical and mineral chemical bonds, thereby increasing the total organic carbon storage of the soil.

[0008] This invention can enhance the water retention capacity of soil by promoting the formation of water-stable aggregates, and can also activate soil biodiversity, thus constructing a healthy and self-sustaining soil ecosystem.

[0009] This invention, by adopting a precise implementation model and utilizing local waste resources, enables the technology to have high adaptability and long-term application value, achieving a leap from simple carbon sequestration to systemic ecological function enhancement. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a flowchart of an urban green space soil improvement method based on green space carbon sequestration enhancement provided in an embodiment of the present invention. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. Example

[0013] A method for improving urban green space soil based on enhancing carbon sequestration in green spaces.

[0014] Please refer to Figure 1 This is a flowchart of an urban green space soil improvement method based on green space carbon sequestration enhancement provided in an embodiment of the present invention.

[0015] S1. Conduct soil quality diagnosis on the target green space, prepare functional soil matrix based on the diagnosis results, and replace the soil in the root zone of the plants. S101, take soil samples at depths of 0-20cm and 20-40cm from the green space where construction is required, and measure the soil bulk density, pH value, initial organic carbon content and compaction. It should be noted that the sampling standard is as follows: the target green area is divided into grids of 10m×10m to 20m×20m, and a sampling point is determined at the center of each grid. Soil samples are taken from the main root system and microbial activity layer (0-20cm) and deep root influence layer (20-40cm) at the sampling point using a soil auger. After removing stones and roots, the samples are mixed and placed in sample bags for laboratory determination of pH value and initial organic carbon content. At the same time, in the adjacent grids of the same sampling point, undisturbed soil samples are taken from depths of 0-20cm and 20-40cm using a ring cutter for determination of soil bulk density.

[0016] S102, based on the diagnostic results, a functional soil matrix is ​​prepared. The matrix by volume includes: 40%-55% original soil, 25%-35% garden waste compost, 15%-20% porous mineral carrier and 5% alkaline conditioner. Porous mineral carriers can be zeolite with a particle size of 2-5 mm; alkaline conditioning agents can be lime or gypsum. It should be noted that when the soil bulk density is greater than At the same time, increase the proportion of porous mineral carriers to 20%; When the soil pH is less than 6.0, lime is used as an alkaline conditioner; when the soil pH is greater than 8.0, gypsum is used as an alkaline conditioner; when the soil pH is between 6.0 and 8.0, lime and gypsum are mixed in a 1:1 ratio; when the initial organic carbon content of the soil is less than 1.0%, the proportion of garden waste compost is increased to 55%.

[0017] Taking the soil in a certain area as an example, the soil bulk density is If the pH is 5.9 and the initial organic carbon content of the soil is 1.2%, then the proportion of the prepared functional soil matrix is: 55% original soil, 25% garden waste compost, 15% porous mineral carrier and 5% lime.

[0018] S103 involves excavating planting holes with a depth of ≥60cm at the planned planting sites, and replacing 30-50% of the original soil volume with functional soil substrate.

[0019] It should be noted that the rules for replacing the soil substrate with the original soil are as follows: if the volume of the planting hole is greater than 200L, then 50% of the original soil should be replaced; if the volume of the planting hole is ≤200L, then 30% of the original soil should be replaced.

[0020] For example, a tree pit with a diameter of 80cm and a depth of 60cm has a volume of about 300L, and therefore requires 150L of functional substrate to be backfilled.

[0021] S2, select plants with deep root systems and efficient carbon sequestration functions, and plant them using a structured model; The structured model includes a tree layer, a shrub layer, and a herb layer. The tree layer selects plants with obvious taproots and large fine root biomass, the shrub layer selects plants with well-developed root systems and fast turnover, and the herb layer selects plants with well-developed fibrous root systems and high litter volume. It should be noted that the tree layer can be planted with ash, locust, or beech; the shrub layer can be planted with lespedeza or spirea; the herbaceous layer can be planted with perennial ryegrass or alfalfa; the structured pattern adopts a mixed planting pattern of nitrogen-fixing plants and non-nitrogen-fixing plants. The tree layer is planted in a 5x5 meter grid, the shrub layer is planted in the middle of the tree layer, with 3-5 trees per clump in a dotted pattern, and the clumps are spaced about 2-3 meters apart. The herbaceous layer completely covers the remaining bare ground.

[0022] It should be noted that, with the marked point as the center, dig circular holes with a diameter of 40-80 cm and a depth of 30-40 cm as planting holes for trees; dig strip trenches with a depth of 40-50 cm as planting for shrubs; and plant herbaceous plants among the shrubs and in the understory space.

[0023] S3 is a compound microbial agent that combines aggregate-forming bacteria, high-efficiency carbon-converting bacteria and rhizosphere symbiotic growth-promoting bacteria, and is then inoculated into the root zone in stages during and after plant planting. The proportions of the compound functional microbial agent are: 50% aggregate-forming bacteria, 30% high-efficiency carbon conversion bacteria, and 20% rhizosphere symbiotic growth-promoting bacteria; It should be noted that gelatinous Bacillus can be selected as the aggregate-forming bacteria; brown nitrogen-fixing bacteria can be selected as the highly efficient carbon-converting bacteria; and arbuscular mycorrhizal fungal spores or rhizobia can be selected as the 20% rhizosphere symbiotic growth-promoting bacteria.

[0024] The vaccination uses a two-step method. The total dose for the first step is... CFU / tree, the total inoculation amount for the second step of inoculation is CFU / m² shrubbery area.

[0025] It should be noted that the first step of inoculation is during the plant planting stage. The prepared solid compound microbial agent is mixed evenly with the functional soil matrix prepared in step one at a weight ratio of 1:50 to 1:100, and this mixed soil is backfilled into the root zone of the plants to ensure that the roots are in full contact with the bacteria-containing soil. The second step of inoculation is one month after planting. The same type of solid compound microbial agent is diluted 100 times with a 5% humic acid solution to prepare a microbial agent suspension. This suspension is then sprayed on shrub and herb areas at a rate of 1-2 liters per square meter, ensuring that it penetrates 5-10 centimeters below the surface.

[0026] The compound microbial agent uses thoroughly decomposed organic materials as a carrier. The carrier has a neutral pH value and a moisture content controlled at 30%-40%, and must undergo sterilization treatment. It should be noted that the organic materials can be earthworm castings, well-rotted furfural residue, or wood ash.

[0027] The preparation process of the compound microbial agent is as follows: the amplified gelatinous Bacillus spores solution and the brown nitrogen-fixing bacteria solution are mixed at a volume ratio of 5:3 and evenly sprayed onto the carrier for thorough stirring. Arbuscular mycorrhizal fungi agent is added at 10%-15% by weight of the mixture, and rhizobium agent is added at 5% by weight. The mixture is then mechanically mixed again until uniform.

[0028] It should be noted that the mixed moistened microbial agent needs to be dispensed into breathable sterile bags and aged in a cool place at room temperature for 24-48 hours to promote initial adaptation of the microbial community and form a ready-to-use solid compound microbial agent. S4, add mineral stabilizers rich in polyvalent metal ions to the soil and lay an organic mulch composed of different functional layers on the surface; S401, a mineral stabilizer rich in polyvalent metal ions is evenly mixed into the topsoil of the plant root zone; Polyvalent metal ions include iron, aluminum, and calcium. The dosage of minerals rich in iron or aluminum is... The dosage of calcium-rich minerals is ; It should be noted that one or more metal ions can be used in the formulation; if the mineral application agent contains both iron and calcium, the one with the larger dosage should be mixed into the upper soil layer.

[0029] S402, a double-layer organic cover layer is laid on the topsoil of the plant root zone; The double-layer structure consists of a 3-5cm thick coarse-grained buffer layer in the lower layer and a 5-8cm thick carbon source habitat layer in the upper layer.

[0030] The material inhabited by the carbon source consists of a mixture of wood chips, garden compost, and biochar, which accounts for 10%-20% of its total weight. The coarse-particle buffer layer is made of branches and trunks that have been crushed by a shredder, with the particles kept in fragments 1-3 cm long.

[0031] It should be noted that the process of laying the organic mulch layer is as follows: After adding mineral stabilizers and mixing thoroughly, remove large stones and impurities from the soil surface and level it simply; use a small paver to evenly lay the pre-treated coarse-grained material to a thickness of 3-5 cm; on top of the lower layer, continue to evenly lay the mixed upper layer material to a thickness of 5-8 cm. Ensure that the total thickness of the mulch layer does not exceed 12 cm after laying. It should be slightly thinned or left open near the base of the plant roots (within a radius of about 5-10 cm) to prevent root rot caused by prolonged excessive moisture.

[0032] Without departing from the purpose and technical effect of this invention, the parameters such as the amount of microbial inoculation, the amount of mineral stabilizer applied, and the thickness of the organic cover layer involved in the above embodiments can be adjusted within ±20% according to specific soil conditions and plant configuration.

[0033] The compound microbial agent includes at least one aggregate-forming microorganism, at least one carbon conversion microorganism, and at least one rhizosphere symbiotic growth-promoting microorganism.

[0034] S5 involves regularly monitoring key soil indicators and implementing adaptive maintenance management of the soil carbon sequestration system based on the monitoring results. S501, Establish a multi-level monitoring system to obtain key soil indicator data; The multi-level monitoring system includes a rapid monitoring layer, a periodic assessment layer, and a biological observation layer; It should be noted that the rapid monitoring layer is used to monitor soil volumetric water content, temperature, and electrical conductivity daily; the periodic assessment layer is used to assess and determine soil bulk density, the proportion of water-stable aggregates >0.25mm, total soil organic carbon, and mineral-bound organic carbon content; and the bioobservation layer is used to periodically record plant growth indicators.

[0035] S502, construct decision-making logic, trigger and execute specific adaptive maintenance measures based on monitoring data; The decision-making logic involves comparing the core data of the periodic assessment layer with preset thresholds or growth trends, and triggering corresponding maintenance instructions based on different scenarios. It should be noted that when the proportion of water-stable aggregates stagnates or decreases, an instruction is triggered to supplement inoculate with aggregate-forming inoculants mainly composed of gelatinous Bacillus; when the total organic carbon content of the soil enters a plateau period, an instruction is triggered to stimulate new carbon input by thinning and replanting or applying functional organic mulch; when the proportion of mineral-bound organic carbon in the total organic carbon is low, an instruction is triggered to supplement with mineral stabilizers rich in at least one polyvalent metal ion among iron, aluminum, and calcium.

[0036] S503 establishes management records, enabling traceability and verification of carbon sequestration effects.

[0037] It should be noted that the management records include: recording all monitoring data, the maintenance operations performed and their timing, and calculating and archiving the annual change in soil carbon storage per unit area based on soil organic carbon data from the periodic assessment layer using internationally or nationally recognized metrological methods.

[0038] Furthermore, it should be noted that the present invention can be provided as a method, apparatus, or computer program product. Therefore, embodiments of the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, embodiments of the present invention can take the form of a computer program product implemented on one or more computer-usable storage media containing computer-usable program code.

[0039] The embodiments of the present invention are described with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0040] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing terminal equipment to cause a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0041] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0042] Finally, it should be noted that the above description represents a preferred embodiment of the present invention. It should be pointed out that although preferred embodiments have been described, those skilled in the art, once they understand the basic inventive concept of the present invention, can make various improvements and modifications without departing from the principles described herein. These improvements and modifications should also be considered within the scope of protection of the present invention. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present invention.

Claims

1. A method for improving urban green space soil based on enhancing green space carbon sequestration, characterized in that, include: S1. Conduct soil quality diagnosis on the target green space, prepare functional soil matrix based on the diagnosis results, and replace the soil in the root zone of the plants. S2, select plants with deep root systems and efficient carbon sequestration functions to construct a three-dimensional community combining trees, shrubs and herbs, and adopt a structured planting model; S3 is a compound microbial agent that combines aggregate-forming bacteria, high-efficiency carbon-converting bacteria and rhizosphere symbiotic growth-promoting bacteria, and is then inoculated into the root zone in stages during and after plant planting. S4, add mineral stabilizers rich in polyvalent metal ions to the soil and lay an organic mulch composed of different functional layers on the surface; S5 involves regularly monitoring key soil indicators and implementing adaptive maintenance management of the soil carbon sequestration system based on the monitoring results.

2. The method for improving urban green space soil based on enhanced carbon sequestration in green space as described in claim 1, characterized in that, S1 involves soil quality diagnosis of the target green space, preparation of functionalized soil matrix based on the diagnosis results, and soil replacement in the plant root zone, wherein: S101, take soil samples at depths of 0-20cm and 20-40cm from the green space where construction is required, and measure the soil bulk density, pH value, initial organic carbon content and compaction. S102, Prepare a functional soil matrix according to the diagnostic results. The matrix comprises, by volume, 40%-55% original soil, 25%-35% garden waste compost, 15%-20% porous mineral carrier and 5% alkaline conditioner. The porous mineral carrier can be zeolite with a particle size of 2-5 mm; the alkaline conditioning agent can be lime or gypsum. S103 involves excavating planting holes with a depth of ≥60cm at the planned planting sites, and replacing 30-50% of the original soil volume with functional soil substrate.

3. The method for improving urban green space soil based on enhanced carbon sequestration in green space as described in claim 1, characterized in that, S2 selects plants with deep root systems and efficient carbon sequestration functions, and cultivates them using a structured planting method, wherein: The structured pattern includes a tree layer, a shrub layer, and a herb layer. The tree layer is composed of plants with prominent taproots and large fine root biomass. The shrub layer is composed of plants with well-developed root systems and fast turnover. The herb layer is composed of plants with well-developed fibrous root systems and high litter volume. The tree layer is planted in a staggered 5x5 meter grid, the shrub layer is planted in the middle of the tree layer, with 3-5 trees per clump in a dotted pattern, and the clump spacing is about 2-3 meters. The herbaceous layer completely covers the remaining bare ground surface.

4. The method for improving urban green space soil based on enhanced carbon sequestration in green space as described in claim 1, characterized in that, S3 involves preparing a compound microbial agent from aggregate-forming bacteria, highly efficient carbon-converting bacteria, and rhizosphere symbiotic growth-promoting bacteria, which is then inoculated into the root zone in stages during and after plant planting. The compound functional microbial agent has the following proportions: 50% aggregate-forming bacteria, 30% high-efficiency carbon-converting bacteria, and 20% rhizosphere symbiotic growth-promoting bacteria. The vaccination uses a two-step method, with the total vaccination dose in the first step being... CFU / tree, the total inoculation amount in the second step of inoculation is CFU / m² shrubbery area.

5. The method for improving urban green space soil based on enhanced carbon sequestration in green space as described in claim 4, characterized in that, The compound microbial agent is prepared by combining aggregate-forming bacteria, highly efficient carbon-converting bacteria, and rhizosphere symbiotic growth-promoting bacteria, wherein: The compound microbial agent uses thoroughly decomposed organic materials as a carrier. The carrier has a neutral pH value and a water content controlled at 30%-40%, and must undergo sterilization treatment. The preparation process of the compound microbial agent is as follows: the amplified gelatinous Bacillus spores solution and the brown nitrogen-fixing bacteria solution are mixed at a volume ratio of 5:3 and evenly sprayed onto the carrier for thorough stirring. Arbuscular mycorrhizal fungi agent is added at 10%-15% by weight of the mixture, and rhizobium agent is added at 5% by weight. The mixture is then mechanically mixed again until uniform.

6. The method for improving urban green space soil based on enhanced carbon sequestration in green space as described in claim 1, characterized in that, S4 involves adding a mineral stabilizer rich in polyvalent metal ions to the soil and laying an organic mulch composed of different functional layers on the surface, wherein: S401, a mineral stabilizer rich in polyvalent metal ions is evenly mixed into the topsoil of the plant root zone; The polyvalent metal ions include iron, aluminum, and calcium, with the dosage of minerals rich in iron or aluminum being [specific dosage missing]. The dosage of calcium-rich minerals is ; S402, a double-layer organic cover layer is laid on the topsoil of the plant root zone; The double-layer structure consists of a 3-5cm thick coarse-particle buffer layer in the lower layer and a 5-8cm thick carbon source habitat layer in the upper layer.

7. The method for improving urban green space soil based on enhanced carbon sequestration in green space as described in claim 6, characterized in that, The method involves laying a double-layered organic cover layer on the surface soil of the plant root zone, wherein: The material inhabited by the carbon source is composed of a mixture of sawdust, garden compost, and biochar, which accounts for 10%-20% of its total weight. The coarse-particle buffer layer is made of branches and trunks that have been crushed by a pulverizer, with the particles kept in fragments 1-3 cm long.

8. The method for improving urban green space soil based on enhanced carbon sequestration in green space as described in claim 1, characterized in that, S5 involves regular monitoring of key soil indicators and adaptive maintenance management of the soil carbon sequestration system based on the monitoring results, including: S501, Establish a multi-level monitoring system to obtain key soil indicator data; The multi-level monitoring system includes a rapid monitoring layer, a periodic assessment layer, and a biological observation layer; S502, construct decision-making logic, trigger and execute specific adaptive maintenance measures based on monitoring data; The decision-making logic involves comparing the core data of the periodic assessment layer with preset thresholds or growth trends, and triggering corresponding maintenance instructions based on different scenarios. S503 establishes management records, enabling traceability and verification of carbon sequestration effects.

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