Method for combining and matching indigenous plants for ecological restoration of bare high and steep slope

Abstract

The invention discloses an indigenous plant combination and matching method for ecological restoration of an exposed high and steep slope, and relates to the technical field of ecological restoration of high and steep slopes, and the indigenous plant combination and matching method comprises the following steps: step 1, investigating a target area; step 2, carrying out primary screening treatment on the indigenous plants, wherein the primary screening treatment comprises formulating an exclusion standard and a retention standard; 3, performing multi-dimensional index quantitative evaluation; 4, building a plant combination according to five rules according to an evaluation result; 5, verification and adjustment are carried out; 6, determining a final combination; and 7, constructing a succession model of the pioneer plant and the apical pole plant. The method has long-term stability: the screened indigenous plants are drought-resistant and barren-resistant, the survival rate of the restored indigenous plants in 20 years can still reach 70% or above, and the limitation that foreign plants are degraded in 3-5 years is broken through; ecological integrity: functional complementation (nitrogen fixation, nectar source and soil fixation) promotes soil improvement and ecological chain construction, and soil organic matters can be increased by 0.3%-0.5% after one year.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ecological restoration of high and steep slope, in particular to a native plant combination matching method for ecological restoration of bare high and steep slope. BACKGROUND

[0002] The bare high and steep slope is a difficulty in the field of ecological restoration, which has poor soil (organic matter content <1%), poor water retention capacity (field moisture capacity <20%), and high slope (≥45°), making it extremely difficult for plants to establish. The traditional restoration mode aims to achieve rapid coverage, mainly using exotic fast-growing plants (such as bahia grass and amsonia), and achieving short-term vegetation coverage through artificial soil covering and spray seeding. However, this mode has obvious limitations: the compatibility of exotic plants with the local ecosystem is poor, and they are prone to die due to drought and barrenness; the community function is single, and it cannot improve the soil conditions; the root structure is unreasonable, and it is easy to cause slope instability in the long term.

[0003] In recent years, the near-natural restoration concept has emerged, emphasizing the use of native plants to build stable communities. However, the existing technology has not yet formed a systematic screening method for bare high and steep slopes, resulting in the application of native plants relying on experience and lacking scientific standards.

[0004] ① The existing technology relies on exotic fast-growing plants (such as amsonia and dog tooth grass), which have poor ecological adaptability (prone to die due to local extreme climate / soil stress), leading to community degradation and slope re-baring after 3-5 years of restoration.

[0005] ② The existing plant screening focuses on "short-term coverage speed" and ignores functional diversity (such as only selecting soil-fixing plants, lacking nitrogen-fixing and nectar source auxiliary functions), resulting in the inability to improve soil fertility and the fragility of the ecological system.

[0006] ③ The existing plant combination does not consider root function complementation, and mostly uses single shallow-rooted plants, which can short-term soil fixation but cannot anchor deep soil, easily causing landslides and other geological disasters.

[0007] ④ The existing scheme lacks community succession design, only planting pioneer plants (such as fast-growing herbs), without matching climax plants (shrubs / trees), leading to the absence of replacement species after the decline of pioneer plants, and the interruption of community stability.

[0008] ⑤ The existing plant propagation relies on artificial seeding or transplanting, ignoring the natural propagation ability of native plants, increasing the cost of restoration and making it difficult to form a self-renewing community. SUMMARY

[0009] The purpose of the present application is to provide a native plant combination matching method for ecological restoration of bare high and steep slope, to solve the problems raised in the background art.

[0010] In order to achieve the above object, the present application provides the following technical scheme: a native plant combination matching method for exposed high and steep slope ecological restoration, comprising the following steps:

[0011] Step one: investigate the target area, and the investigation includes target slope feature investigation and native plant background investigation;

[0012] Step two: preliminarily screen the native plants, and the preliminary screening includes formulating exclusion criteria and retention criteria;

[0013] Step three: multi-dimensional index quantification evaluation, and the evaluation includes ecological adaptability, functional diversity, reproductive characteristics, root functionality and community complementarity to determine the weight score, and the preferred standard is proposed;

[0014] Step four: according to the results after evaluation, construct plant combination according to five rules, including root system matching, functional matching, reproductive matching and community succession matching;

[0015] Step five: verification and adjustment, including small area test planting, verification index and adjustment rule;

[0016] Step six: determine the final combination, after verification, output the native plant combination list, and clearly indicate the proportion, planting method and maintenance points of each plant;

[0017] Step seven: construct a succession model of pioneer plants and climax plants, from bare rock stabilization to functional climax community, with slope stability improvement and soil-water condition improvement as the double driving axes, divided into four stages.

[0018] Preferably, the target slope feature investigation in step one includes determining slope, slope direction, soil physical and chemical properties and climate data;

[0019] The native plant background investigation includes investigating the existing native plant species and growth conditions within 5km range around the target area.

[0020] Preferably, the exclusion criteria in step two include ① non-native plants (exotic species, such as Amorpha fruticosa), ② known invasive species, ③ plants that have destructive effect on the slope;

[0021] The retention criteria include ① naturally distributed on the high and steep slope around the target area, ② no degradation or death cases in historical records.

[0022] Preferably, the multi-dimensional index quantification evaluation model and screening formula in step three are as follows:

[0023] (1) Standardize each index, and the standardization formula is;

[0024] ;

[0025] wherein is the original value of the jth indicator of the ith evaluation object, , is the maximum value and the minimum value of the jth indicator, respectively;

[0026] (2) Calculate the proportion of each indicator:

[0027] ;

[0028] wherein is the number of evaluation objects;

[0029] (3) Calculate the information entropy of each indicator;

[0030] ;

[0031] wherein if , then define ;

[0032] (4) Calculate the entropy weight of each dimension indicator; including calculating the redundancy of information entropy and calculating the entropy weight:

[0033] Calculate the redundancy of information entropy;

[0034] ;

[0035] Calculate the entropy weight;

[0036] ;

[0037] For the weight of the five dimensions, first take each dimension as a comprehensive indicator, and calculate the weight of each indicator in the dimension according to the above method, which satisfies that the weights of the indicators in the same dimension satisfy ;

[0038] (5) Standardization processing of each indicator:

[0039] Standardize the quantitative value of each indicator to make it in the range of 0-10, and the standardization formula is: standardized score=(actual value-minimum value) / (maximum value-minimum value) x 10;

[0040] (6) Calculate the score of each dimension:

[0041] Each dimension score=the standardized score of each indicator in the dimension x the sum of the weights of the corresponding indicators in the dimension.

[0042] Preferably, the plant combination in step four is constructed according to the following rules:

[0043] (1) Root system matching: 1-2 deep-rooted plants + 2-3 shallow-rooted plants;

[0044] (2) Functional combination: at least one nitrogen-fixing plant + one nectar plant + one soil-strengthening plant;

[0045] (3) Reproduction combination: seed-dispersing plants combined with vegetative reproduction plants;

[0046] (4) Community succession combination: pioneer herbs + climax shrubs + climax trees.

[0047] Preferably, the step five verification and adjustment comprises the following;

[0048] (1) Small-area trial planting: select a 100 square meter area on the target slope, plant according to the optimized combination, and monitor for one year;

[0049] (2) Verification indicators: plant survival rate, slope stability, and soil improvement;

[0050] (3) Adjustment rules: if the survival rate of a certain species is <60%, replace it with an alternative native plant with the same function.

[0051] Preferably, the four stages divided in step seven are as follows;

[0052] (1) Bare rock stabilization stage - pioneer plant site stage (0-2 years):

[0053] In this stage, coverage is mainly covered by pioneer herbaceous plants, with a coverage of 55%. Pioneer plants quickly cover the rock surface through stolon and fibrous roots, intercepting precipitation and creating a slightly humid environment for subsequent species. Nitrogen-fixing pioneer plants continuously improve soil fertility and organic matter content, providing biological energy for community succession and improving soil conditions;

[0054] (2) Pioneer-shrub transition stage (2-5 years):

[0055] Pioneer herbs (maintain a proportion of 55%) + native primary shrubs (15%);

[0056] The plant coverage of the bare slope reaches 70%, and the deep roots of native shrubs penetrate the rock joints, forming a "deep-shallow root network" with shallow-rooted herbs, and the slope stabilization effect is improved to 80%;

[0057] Soil organic matter increases from 1% to 3%-5%, providing a nutrient base for the growth of top-level trees and shrubs.

[0058] Preferably, the four stages divided in step seven further comprise the following:

[0059] (3) Top community construction stage (5-8 years):

[0060] Pioneer herbs (proportion reduced to 40%) + climax shrubs (25%) + climax trees (15%);

[0061] The coverage is maintained at 70-80%, further improving the stability of the slope body;

[0062] The decomposition rate of fallen leaves reaches 60% (higher than ordinary trees), accelerating soil formation (0.3-0.5 cm per year), and solving the problem of soil deficiency on the slope;

[0063] The roots of deep-rooted trees and shrubs intersect in rock joints, forming a "biological anchor system", and the slope anti-sliding force is improved by 50%, achieving dynamic stability;

[0064] (4) Top stable stage (after 8 years):

[0065] The ratio of pioneer herbs (40%), top shrubs (30%) and top trees (25%) is stable in the long term, and the coverage is maintained at 85% (to avoid excessive self-weight leading to landslides);

[0066] The ecological protection function (slope fixation, erosion reduction) of the top community is improved by 40-60% compared with single species, achieving the repair goal of "rapid stability-long-term sustainability".

[0067] Compared with the prior art, the beneficial effects of the present application are:

[0068] 1. The present application has the following advantages:

[0069] ① Long-term stability: The selected native plants are drought-tolerant and poor-tolerant, and the survival rate after 20 years of repair can still reach more than 70%, breaking through the limitations of three to five years of degradation of exotic plants;

[0070] ② Ecological integrity: Functional complementarity (nitrogen fixation + nectar source + soil fixation) promotes soil improvement and ecological chain construction, and the soil organic matter can be improved by 0.3-0.5% after 1 year;

[0071] ③ Slope safety: Deep roots and shallow roots are matched to improve the slope anti-sliding force by more than 40%, reducing the risk of geological disasters;

[0072] ④ Low-cost maintenance: Strong natural reproduction ability, no need for artificial reseeding in the later period, annual maintenance cost reduced to <100 yuan / mu;

[0073] ⑤ Natural succession sustainability: Pioneer plants and climax plants form a stable sequence, and the community coverage rate is stable at more than 90% after five years, achieving the goal of near-natural restoration.

[0074] 2. The present application also has the following advantages:

[0075] ① Multi-dimensional screening criteria: Integrating quantitative index system of ecological adaptability, functional diversity, reproductive characteristics, root functionality and community complementarity provides scientific basis for screening native plants for bare high and steep slopes;

[0076] ②Root system function matching method: combination rule of deep root (main root > 30 cm) and shallow root (lateral root density > 50 per square meter), considering anchoring and soil fixation;

[0077] ③Community succession design: ratio (40%-50%:50%-60%) and matching logic of pioneer plant and climax plant, ensuring stable succession;

[0078] ④Natural reproduction priority principle: screening of species with seed propagation distance > 5 m or vegetative reproduction survival rate > 80%, reducing artificial intervention;

[0079] ⑤Quantitative evaluation method: repeatable detection means such as 30-day drought survival rate detection of drought resistance and root tensile strength detection of soil fixation capacity. BRIEF DESCRIPTION OF DRAWINGS

[0080] Figure 1 The overall method flowchart of the embodiment of the present application is provided. DETAILED DESCRIPTION

[0081] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0082] Please refer to Figure 1 The present application provides a technical solution: a native plant combination matching method for ecological restoration of exposed high and steep slope, comprising the following steps:

[0083] Step 1: Investigate the target area, and the investigation includes target slope feature investigation and native plant background investigation;

[0084] Step 2: Preliminary screening of native plants, and the preliminary screening includes exclusion criteria and retention criteria;

[0085] Step 3: Multi-dimensional index quantitative evaluation, and the evaluation includes ecological adaptability, functional diversity, reproductive characteristics, root system functionality and community complementarity to determine weight score, and preferred standard is proposed;

[0086] Step 4: According to the results after evaluation, plant combination is constructed according to five rules, including root system matching, function matching, reproduction matching and community succession matching;

[0087] Step 5: Verification and adjustment, including small area test planting, verification index and adjustment rule;

[0088] Step six: Determine the final combination, after verification, output the list of native plant combinations, clear the proportion of each plant, planting method (seedling / cutting) and maintenance points;

[0089] Step seven: Construct the succession model of pioneer plants and climax plants, from bare rock stabilization to functional climax community, with slope stability improvement and soil-water condition improvement as the double driving axes, divided into four stages.

[0090] The target slope feature investigation in step one includes determining the slope (≥ 45° needs to be marked), slope direction (sunny / shady), soil physical and chemical properties (organic matter content, pH value, water content) and climate data (annual average precipitation, extreme high / low temperature);

[0091] Example: A mine slope with a slope of 55°, sunny, soil organic matter 0.8%, pH = 8.2, annual average precipitation 550mm, extreme high temperature 40℃;

[0092] The native plant background investigation includes investigating the existing native plant species (record genus, growth location) and growth conditions (coverage, height, survival rate) within 5km around the target area;

[0093] Pay special attention to "naturally planted on high and steep slopes" native plants (such as wolf tooth, white sheep grass, etc.), excluding species that only grow on flat land.

[0094] The exclusion criteria in step two include ① non-native plants (exotic species, such as Amorpha fruticosa), ② known invasive species (such as ragweed), ③ plants that have destructive effects on slopes (such as tree species that cause soil drought due to strong transpiration);

[0095] The retention criteria include ① naturally distributed on high and steep slopes around the target area, ② no degradation or death cases in historical records.

[0096] The ecological adaptability, functional diversity, reproductive characteristics, root function and community complementarity in step three are shown in the following table;

[0097]

[0098] And the multi-dimensional index quantitative evaluation model and screening formula are as follows;

[0099] (1) Standardize each index, the standardization formula is;

[0100] ;

[0101] Wherein is the original value of the jth indicator of the ith evaluation object, 、 The maximum and minimum values of the jth index are respectively;

[0102] (2) Calculate the proportion of each index:

[0103] ;

[0104] Wherein is the number of evaluation objects;

[0105] (3) Calculate the information entropy of each index;

[0106] ;

[0107] Wherein if , define ;

[0108] (4) Calculate the entropy weight of each dimension index; including calculating the redundancy of information entropy and calculating the entropy weight:

[0109] Calculate the redundancy of information entropy;

[0110] ;

[0111] Calculate the entropy weight;

[0112] ;

[0113] For the weight of the five dimensions, first take each dimension as a comprehensive index, and calculate the weight of each index in the dimension according to the above method, which satisfies the weight of each index in the same dimension ;

[0114] (5) Standardization processing of each index:

[0115] Standardize the quantitative value of each index to make it in the range of 0-10, and the standardization formula is: standardized score=(actual value-minimum value) / (maximum value-minimum value)×10;

[0116] (6) Calculate the score of each dimension:

[0117] Each dimension score=each index standardized score in the dimension×the weight of the corresponding index in the dimension.

[0118] The plant combination in step four is constructed according to the following rules:

[0119] (1) Root system matching: 1-2 deep-rooted plants+2-3 shallow-rooted plants;

[0120] (2) Functional matching: at least containing 1 nitrogen-fixing plant+1 nectar plant+1 strong soil plant;

[0121] (3) Reproduction matching: seed-dispersing plants combined with vegetative reproduction plants;

[0122] (4) Community succession combination: pioneer herb (40%-50%) + climax shrub (30%-40%) + climax tree (10%-20%).

[0123] The step five verification and adjustment includes the following;

[0124] (1) Small area test planting: select a 100 square meter area on the target slope, plant according to the optimized combination, and monitor for 1 year;

[0125] (2) Verification index: plant survival rate (>80%), slope stability (no landslide / collapse), and soil improvement (organic matter improvement >0.2%);

[0126] (3) Adjustment rule: if the survival rate of a certain species is <60%, replace it with an alternative native plant with the same function (such as replacing the low survival rate of sandwort with huizhi).

[0127] The four stages divided in step seven are as follows;

[0128] (1) Bare rock stabilization stage - pioneer plant site stage (0-2 years):

[0129] In this stage, the coverage is mainly covered by pioneer herbaceous plants, with a coverage of 55%. Pioneer plants quickly cover the rock surface through creeping stems and root hairs, intercepting precipitation and creating a slightly humid environment for subsequent species. Nitrogen-fixing pioneer plants continuously improve soil fertility and organic matter content, providing biological energy for community succession and improving soil conditions;

[0130] (2) Pioneer-shrub transition stage (2-5 years):

[0131] Pioneer herb (occupying 55%) + native primary shrub (15%);

[0132] The plant coverage of the bare slope reaches 70%, and the deep roots of the native shrubs penetrate the rock joints, forming a "deep-shallow root network" with the shallow roots of the herbaceous plants, and the slope stabilization effect is improved to 80%;

[0133] Soil organic matter is increased from 1% to 3%-5%, providing a nutrient base for the growth of top-level trees and shrubs;

[0134] (3) Top community construction stage (5-8 years):

[0135] Pioneer herb (occupying 40%) + climax shrub (25%) + climax tree (15%);

[0136] The coverage is maintained at 70%-80%, further improving the stability of the slope;

[0137] Deciduous trees decompose at a rate of 60% per year (higher than ordinary trees), accelerating soil formation (0.3-0.5 cm per year), and solving the problem of soil deficiency on slopes;

[0138] Deep-rooted trees and shrubs intersect in rock crevices, forming a "biological anchor system", and the slope's anti-sliding force is increased by 50%, achieving dynamic stability.

[0139] (4) Top-stable stage (after 8 years):

[0140] The ratio of pioneer herbs (40%), top shrubs (30%), and top trees (25%) is stable in the long term, and the coverage rate is maintained at 85% (to avoid excessive self-weight leading to landslides);

[0141] The ecological protection function (slope fixation and erosion reduction) of the top community is 40%-60% higher than that of single species, achieving the goal of "rapid stability and long-term sustainability" of restoration.

[0142] It should be noted that, in this document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0143] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, alternatives, and variations can be made in the embodiments without departing from the spirit and scope of the present application as defined by the appended claims and their equivalents.

Claims

1. A method for combining native plants for ecological restoration of exposed, steep slopes, characterized in that: The method comprises the following steps: Step 1: Investigate the target area, including target slope feature investigation and native plant background investigation; Step 2: Preliminary screening of native plants, including the establishment of exclusion criteria and retention criteria; Step 3: Multi-dimensional index quantification evaluation, including ecological adaptability, functional diversity, reproductive characteristics, root functionality and community complementarity to determine the weight score, and the preferred standard is proposed; Step 4: According to the results of the evaluation, construct plant combinations according to five rules, including root system matching, function matching, reproduction matching and community succession matching; Step 5: Verification and adjustment, including small area test planting, verification index and adjustment rule; Step 6: Determine the final combination, output the list of native plant combinations after verification, and clearly define the proportion, planting method and maintenance points of each plant; Step 7: Construct a succession model of pioneer plants and climax plants, from bare rock stabilization to functional climax community, with slope stability improvement and soil-water condition improvement as the double driving axes, and divide it into four stages.

2. The native plant combination collocation method for ecological restoration of exposed high and steep slope according to claim 1, characterized in that: The target slope feature investigation in step 1 includes determining slope, slope direction, soil physical and chemical properties and climate data; The native plant background investigation includes investigating the existing native plant species and growth conditions within a 5km range around the target area.

3. The native plant combination collocation method for ecological restoration of exposed high and steep slope according to claim 2, characterized in that: The exclusion criteria in step 2 include ① non-native plants (exotic species such as Amorpha fruticosa), ② known invasive species, and ③ plants that have a destructive effect on the slope; The retention criteria include ① naturally distributed on the high and steep slopes around the target area, and ② no degradation or death cases in historical records.

4. The native plant combination collocation method for ecological restoration of exposed high and steep slope according to claim 3, characterized in that: The multi-dimensional index quantification evaluation model and screening formula in step 3 are as follows; (1) Standardize each index, the standardization formula is; ； wherein is the original value of the jth indicator of the ith evaluation object, , are the maximum and minimum values, respectively, of the jth indicator. (2) Calculate the proportion of each index: ； wherein is the number of evaluation objects; (3) Calculate the information entropy of each index; ； wherein if then define ; (4) Calculate the entropy weight of each dimension index, including calculating the redundancy of information entropy and calculating the entropy weight: Calculate the redundancy of information entropy; ； Calculate the entropy weight; ； For the weight of the five dimensions, each dimension is first taken as a comprehensive index, and the weight of each index in the dimension is calculated according to the above method, which satisfies the same weight of each index in the dimension ; (5) Standardize each index: Standardize the quantified value of each index to make it within the range of 0-10, the standardization formula is: standardized score = (actual value-minimum value) / (maximum value-minimum value) x 10; (6) Calculate the score of each dimension: Each dimension score = the standardized score of each index in this dimension x the weight sum of the corresponding index in this dimension.

5. The native plant combination collocation method for ecological restoration of exposed high and steep slope according to claim 4, characterized in that: The plant combination is constructed according to the following rules in step 4: (1) Root system matching: 1-2 deep-rooted plants + 2-3 shallow-rooted plants; (2) Function matching: at least 1 nitrogen-fixing plant + 1 nectar plant + 1 strong soil plant; (3) Reproduction matching: seed-dispersing plants combined with vegetative reproduction plants; (4) Community succession matching: pioneer herbs + climax shrubs + climax trees.

6. The native plant combination collocation method for ecological restoration of exposed high and steep slope according to claim 5, characterized in that: The verification and adjustment in step 5 include the following: (1) Small area test planting: select a 100㎡ area on the target slope, plant according to the optimized combination, and monitor for 1 year; (2) Verification index: plant survival rate, slope stability and soil improvement; (3) Adjustment rule: if the survival rate of a certain species is <60%, replace it with a backup native plant with the same function.

7. The native plant combination collocation method for exposed high and steep slope ecological restoration according to claim 6, characterized in that: The four stages divided in step seven are as follows: (1) Bare rock stabilization stage - pioneer plant site stage (0-2 years): In this stage, coverage is dominated by pioneer herbaceous plants, with a coverage of 55%. Pioneer plants quickly cover the rock surface through stolon and fibrous roots, intercepting precipitation and creating a slightly humid environment for subsequent species. Nitrogen-fixing pioneer plants continuously improve soil fertility and organic matter content, providing biological energy for community succession and improving soil conditions; (2) Pioneer-shrub transition stage (2-5 years): Pioneer herbs (accounting for 55%) + native primary shrubs (accounting for 15%); Plant coverage on bare slopes reaches 70%, and the deep roots of native shrubs penetrate rock crevices, forming a "deep-shallow root network" with shallow-rooted herbs, and the slope stabilization effect is improved to 80%; Soil organic matter increases from 1% to 3%-5%, providing a nutrient base for the growth of top-level trees and shrubs.

8. The native plant combination collocation method for ecological restoration of exposed high and steep slope according to claim 7, characterized in that: The four stages divided in step seven also include the following: (3) Top community construction stage (5-8 years): Pioneer herbs (accounting for 40%) + top shrubs (25%) + top trees (15%); Coverage is maintained at 70%-80%, further improving slope stability; Deciduous annual decomposition rate reaches 60% (higher than ordinary trees), accelerating soil formation (annual thickening 0.3-0.5 cm), solving the problem of slope soil deficiency; Deep-rooted trees and shrubs form a "biological anchor system" in rock crevices, increasing slope resistance by 50% and achieving dynamic stability; (4) Top stabilization stage (after 8 years): The proportion of pioneer herbs (40%) + top shrubs (30%) + top trees (25%) is stable in the long term, and the coverage is maintained at 85% (to avoid excessive weight leading to landslides); The ecological protection function (slope stabilization, erosion reduction) of the top community is improved by 40%-60% compared to single species, achieving the goal of "rapid stabilization and long-term sustainability" in restoration.

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