Comprehensive evaluation method for vegetation restoration capability of bare soil of tower footing of power transmission line

Abstract

The invention discloses a power transmission line tower footing bare soil vegetation restoration capability comprehensive evaluation method, and relates to the technical field of vegetation restoration capability evaluation, and the method comprises the steps: building an evaluation index system, building a quantitative model, carrying out data collection, and carrying out calculation and grading. According to the method, a comprehensive evaluation index system is constructed, electromagnetic radiation related indexes and microtopography related indexes are covered, the actual vegetation restoration situation can be reflected more accurately, the influence coefficient is measured and calculated in detail, the influence of electromagnetic radiation and microtopography changes on vegetation is fully considered, a basis is provided for accurate evaluation, and the vegetation restoration efficiency is improved. The problems of inaccurate and incomplete evaluation are effectively solved, quantitative model construction and optimization are performed, time factors are introduced to dynamically evaluate the vegetation restoration capability, problems can be found in time, a restoration strategy can be adjusted, accurate grade division is performed, reasonable selection of vegetation varieties is facilitated, proper restoration measures are adopted, the vegetation restoration success rate is increased, and the vegetation restoration efficiency is improved. The ecological stability of the tower footing area is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of vegetation restoration capability evaluation, and in particular to a comprehensive evaluation method for vegetation restoration capability of bare soil at a tower foundation of a power transmission line. Background Art

[0002] In today's society, the demand for electric energy continues to rise. As a key infrastructure for power transmission, the construction scale of transmission lines is expanding day by day. The construction of transmission line tower bases is an important part of transmission line projects. However, in the process of tower base construction, it is inevitable to cause significant damage to the surrounding natural environment. The original vegetation is removed and the soil structure is disturbed, resulting in the formation of bare soil areas around the tower bases. The existence of bare soil areas has caused a series of serious environmental problems. On the one hand, the soil loses the protection of vegetation and is prone to soil erosion under natural effects such as rain erosion and wind erosion. This will not only cause the rapid loss of soil fertility, but also increase the turbidity of surrounding water bodies and affect water quality. On the other hand, the ecosystem service functions of bare soil areas are lost, such as soil conservation, water conservation, climate regulation and other functions cannot be performed normally. At the same time, for the transmission line itself, the instability of the bare soil area may affect the stability of the tower base, thereby threatening the safe operation of the transmission line. In order to solve the problem of vegetation damage in the construction of overhead transmission line projects, it is necessary to conduct a comprehensive evaluation of the vegetation restoration capacity of the transmission line tower base.

[0003] The existing evaluation methods for bare soil vegetation restoration at the tower base of power transmission lines mostly focus on single or a small number of indicators such as vegetation coverage, and lack comprehensive consideration of special environmental factors of the tower base. There is a complex electromagnetic environment around the tower base, and the electromagnetic radiation generated by it may have a potential impact on vegetation growth, but the existing evaluation methods have not fully incorporated this factor. In addition, the micro-topographic changes caused by tower base construction, such as changes in slope, slope direction and soil compactness, have not received enough attention. This limitation makes the evaluation of vegetation restoration capacity inaccurate and comprehensive, making it difficult to effectively guide vegetation restoration work, and unable to take targeted measures to improve the effect of vegetation restoration, and thus unable to give full play to the important role of vegetation restoration in the ecological protection of bare soil areas and the safe and stable operation of transmission lines. Therefore, it is necessary to propose a comprehensive evaluation method for bare soil vegetation restoration capacity at the tower base of transmission lines to solve the problems in the existing technology. Summary of the invention

[0004] The purpose of the present invention is to make up for the shortcomings of the prior art and provide a comprehensive evaluation method for the vegetation restoration capacity of bare soil at the tower base of a transmission line. It can construct a comprehensive evaluation index system covering electromagnetic radiation-related indicators and micro-topography-related indicators, which can more accurately reflect the actual situation of vegetation restoration, fully consider the impact of electromagnetic radiation and micro-topography changes on vegetation, provide a basis for accurate evaluation, and effectively solve the problem of inaccurate and incomplete evaluation.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a comprehensive evaluation method for the vegetation restoration capacity of bare soil at the tower base of a transmission line, the steps of which include: constructing an evaluation index system, constructing a quantitative model, data collection, and calculation and grading;

[0006] Construct an evaluation index system: Set a circle with a radius of r around the tower base of the transmission line with the tower base as the center. 1 、r 2 、r 3 concentric circles, where r 1 <r 2 <r 3 Monitoring points are set at every angle α on the concentric circles to measure the electromagnetic radiation intensity E, chlorophyll content C of vegetation leaves, cell membrane permeability P and antioxidant enzyme activity A. The electromagnetic radiation influence coefficient IE is calculated according to the formula Calculate, where C 0 , P 0 , A 0 are the average values ​​of chlorophyll content, cell membrane permeability and antioxidant enzyme activity of vegetation leaves under normal environment, C max , P max , A max They are the maximum values ​​of chlorophyll content, cell membrane permeability and antioxidant enzyme activity of plant leaves under laboratory conditions, and a 1 、a 2 、a 3 、a 4 is the weight coefficient, and a 1 +a 2 +a 3 +a 4 =1;

[0007] Measure micro-topography related indicators, including measuring the slope G, slope direction O and soil compactness S of each point in the bare soil area of ​​the tower base. The micro-topography influence coefficient IT is calculated according to the formula Calculate, where G max , O max , S max are the slope, aspect and maximum soil compactness in the study area, respectively. 1 、b 2 、b 3 is the weight coefficient, and b 1 +b 2 +b 3 =1;

[0008] Construct a quantitative model: define the vegetation restoration capacity evaluation index value as V, and the relationship between V and IE and IT is as follows: where c 1、c 2 is the exponential coefficient, 0 <c 1 <1,0 <c 2 <1;

[0009] Data collection: Use a high-precision electromagnetic radiation spectrum analyzer to collect electromagnetic radiation intensity data around the tower base according to a predetermined grid layout; use a total station, a three-dimensional laser scanner, and a soil compaction stratification measuring instrument to collect micro-topography data; collect vegetation samples of different types and different growth stages based on a scientific stratified sampling method; and measure leaf chlorophyll content, cell membrane permeability, and antioxidant enzyme activity in the laboratory;

[0010] Calculation and classification: Substitute the collected data into the quantitative model to calculate the vegetation restoration capacity evaluation index value V, and classify the vegetation restoration capacity level according to the V value. When V≥V 1 For high repair capability level, when V 2 <V<V 1 For medium repair capability level, when V≤V 2 For low repair ability level, V 1 、V 2 is the threshold value.

[0011] Furthermore, the step of measuring the electromagnetic radiation intensity includes:

[0012] At each monitoring point, an electromagnetic radiation spectrum analyzer was used to analyze the frequency band f 1 、f 2 ,…,f n At the same time, the electromagnetic radiation intensity E(f 1 )、E(f 2 ),…,E(f n ), the comprehensive electromagnetic radiation intensity E is calculated according to the formula Calculate, where w i is the frequency band f i The weight coefficient is 0 <w i <1, w i Determined based on the sensitivity analysis experiment of the impact of electromagnetic radiation on vegetation physiological indicators;

[0013] When measuring the antioxidant enzyme activity A, the weighted comprehensive value of superoxide dismutase SOD, peroxidase POD, and catalase CAT activities is used, and the weight is determined according to the importance of each antioxidant enzyme in responding to electromagnetic radiation damage.

[0014] Furthermore, the step of measuring micro-topography related indicators includes: when measuring the slope G, in addition to using the total station to measure the horizontal distance and vertical height difference calculation, multiple measurements are performed in different seasons and under different precipitation conditions, and after measurement, the formula G′=G×(1+k 1×(V g -V g0 )+k 2 ×(P r -P r0 )) correction, where V g is the vegetation coverage at the current measurement, V g0 is the average vegetation coverage of the region over the years, P r To measure the amount of precipitation in the previous period, P r0 is the average precipitation in the region over the same period over the past few years, k 1 , k 2 is the correction factor.

[0015] Furthermore, the step of measuring micro-topography related indicators also includes:

[0016] When measuring the slope aspect O, the slope aspect is converted into numerical form, and the changes of solar altitude angle and azimuth angle in different seasons and at different times are considered. The effective solar radiation received by the slope aspect R is calculated by establishing a solar radiation model. o , R o Used for calculation of micro-topography influence coefficient IT;

[0017] When measuring soil compaction S, at different depths d 1 ,d 2 ,…,d m Layered measurement, weighted average soil compaction where q j is the depth d j The weight coefficient is 0 j <1, The weight coefficient is determined according to the importance of root distribution density and soil layer to vegetation growth.

[0018] Furthermore, the step of determining the quantitative model exponential coefficient includes:

[0019] Long-term vegetation restoration experiments were conducted in several typical transmission line tower base bare soil test areas with different electromagnetic radiation intensities and micro-topography characteristics. The vegetation coverage rate, vegetation species changes and vegetation height growth data at different time points were recorded. The correlation analysis was performed on these data with the corresponding electromagnetic radiation influence coefficient IE and micro-topography influence coefficient IT. The relationship curve was fitted by multivariate nonlinear regression analysis, and the exponential coefficient c was determined according to the curve fitting goodness of fit and the actual vegetation restoration situation. 1 、c 2 ;

[0020] When calculating the vegetation restoration capacity evaluation index value V, the time factor t is introduced, and the formula is: c 1 (t), c​2 (t) is an exponential coefficient that changes with time, and its changing pattern is determined by analyzing and modeling long-term test data.

[0021] Furthermore, the calibration step of the data acquisition instrument includes: when using an electromagnetic radiation spectrum analyzer, calibrating with a standard electromagnetic radiation source at a known intensity, analyzing the calibration error, and measuring according to the formula E′=E×(1+m 1 ×(TT 0 )+m 2 ×(HH 0 )) Corrected measurement results, where E′ is the corrected electromagnetic radiation intensity, T 0 , H 0 The standard measurement environment temperature and humidity, m 1 、m 2 are the temperature and humidity correction factors.

[0022] Furthermore, the calibration steps of the data acquisition instrument also include: regular calibration and accuracy verification of the total station, three-dimensional laser scanner and soil compaction stratification measuring instrument. The total station establishes a control network consisting of multiple reference points, measures the distance and angle deviation between the reference points to evaluate the accuracy, the three-dimensional laser scanner verifies the scanning accuracy with a standard geometric model, and the soil compaction stratification measuring instrument is calibrated with a standard soil sample of known compactness. When collecting vegetation samples, a stratified random sampling method is used according to the density of vegetation distribution and terrain changes, and sampling layers are set in different vegetation communities and terrain areas, and sampling points are randomly selected in each layer.

[0023] Furthermore, before the calculation and classification steps, a data preprocessing step is also included, which step includes:

[0024] The collected electromagnetic radiation intensity data, microtopography data and vegetation physiological index data were tested for outliers using the 3σ principle and box plot method. The 3σ principle states that normally distributed data values ​​outside the mean ±3 times the standard deviation are considered outliers. The box plot method states that data values ​​outside the 1.5 times interquartile range of the upper and lower quartiles are considered outliers. For detected outliers, if they are due to measurement errors and can be corrected retroactively, the data will be corrected. If they are due to special circumstances, the outliers will be retained and marked and specially processed. Measurement errors that can be corrected retroactively include instrument failures and sudden changes in the measurement environment. Special circumstances include local geological anomalies and short-term environmental interference.

[0025] The electromagnetic radiation intensity data were normalized by logarithmic transformation, that is, E″=log(E+1), where E″ is the standardized electromagnetic radiation intensity. The micro-topography data and vegetation physiological index data were normalized by weighted method according to the data range and correlation.

[0026] Furthermore, the vegetation restoration capacity classification is divided into V value and V 1 、V 2 In addition to the three levels of high, medium and low, the threshold V is introduced 3、V4 ,…,V n-1 The vegetation restoration capacity is divided into n levels, where V 1 >V 2 >V 3 >…>V n-1 >V n , n>3, each level has different vegetation restoration strategy recommendations, high restoration capacity level V≥V 1 Divided into high-excellent V≥V 1 +ΔV 1 and high-good V 1 ≤V <V 1 +ΔV 1 , low repair ability level V≤V 2 Divided into low-difference V≤V 2 -ΔV 2 and low-range V 2 -ΔV 2 <V≤V 2 .

[0027] Compared with the existing technology, the comprehensive evaluation method for the vegetation restoration capacity of bare soil at the tower foundation of power transmission lines has the following beneficial effects:

[0028] The present invention constructs a comprehensive evaluation index system, covering electromagnetic radiation-related indicators and micro-topography-related indicators, which can more accurately reflect the actual situation of vegetation restoration. By detailed measurement and calculation of influence coefficients, it fully considers the impact of electromagnetic radiation and micro-topography changes on vegetation, provides a basis for accurate evaluation, and effectively solves the problems of inaccurate and incomplete evaluation. The construction and optimization of the quantitative model introduces time factors to dynamically evaluate the vegetation restoration ability, which can timely discover problems and adjust restoration strategies. The accurate grading helps to reasonably select vegetation varieties and take appropriate restoration measures, thereby improving the success rate of vegetation restoration and enhancing the ecological stability of the tower base area.

[0029] Other advantages, objectives and features of the present invention will be set forth in part in the following description and, in part, will be apparent to those skilled in the art based on an examination of the following or may be taught from the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 This is a flow chart of the comprehensive evaluation method for the vegetation restoration capacity of bare soil at the tower base of transmission lines. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Embodiment 1

[0034] The vegetation restoration capacity was evaluated in the bare soil area of ​​a transmission line tower base in a coastal area. This area is affected by the marine climate, with abundant precipitation and frequent strong winds. At the same time, the soil salinization degree is high, which poses a special challenge to vegetation growth. In addition, the electromagnetic radiation environment around the tower base is complex. This method was used to conduct a comprehensive evaluation.

[0035] First, a multi-layer monitoring area is set up around the base of the transmission line tower (similar to a concentric circle structure with the tower base as the center), and monitoring points are set up at certain angles in different monitoring areas. At each monitoring point, the electromagnetic radiation intensity E, chlorophyll content C of vegetation leaves, cell membrane permeability P and antioxidant enzyme activity A are accurately measured.

[0036] For the electromagnetic radiation influence coefficient IE, according to the formula Calculate, where C 0 , P 0 , A 0 are the average values ​​of chlorophyll content, cell membrane permeability and antioxidant enzyme activity of vegetation leaves under normal environment, C max , P max , A max They are the maximum values ​​of chlorophyll content, cell membrane permeability and antioxidant enzyme activity of plant leaves under laboratory conditions, and a 1 、a 2 、a 3 、a 4 is the weight coefficient, and a 1 +a 2 +a 3 +a 4=1, these parameters are determined based on previous research and field tests.

[0037] At the same time, the slope G, slope direction O and soil compactness S of each point in the bare soil area of ​​the tower base are measured, and the micro-topography influence coefficient IT is calculated according to the formula Calculate, where G max , O max , S m ax are the slope and aspect values ​​and the maximum soil compaction value in the study area, b 1 、b 2 、b 3 is the weight coefficient, and b 1 +b 2 +b 3 =1, the weight coefficient is set according to the terrain characteristics and vegetation growth research of the area.

[0038] Considering the complexity of the influence of slope aspect O on sunlight and sea breeze, a professional model is used to convert it into numerical form, and the effective solar radiation received R is calculated by combining the changes in solar altitude angle and azimuth angle as well as the influence of sea breeze direction. o For IT calculation, soil compaction S is measured at different depths and then calculated according to the formula Calculate the weighted average soil compaction S′, where q j is the depth d j The weight coefficient is 0 j <1, The weight coefficient is determined according to the root distribution characteristics of vegetation in the area.

[0039] At each monitoring point, an electromagnetic radiation spectrum analyzer is used to monitor the 1 、f 2 ,…,f n At the same time, the electromagnetic radiation intensity E(f 1 )、E(f 2 )......E(f n ), the comprehensive electromagnetic radiation intensity E is calculated according to the formula E = Calculate, where w i is the frequency band f i The weight coefficient is 0 <w i <1, w i According to the sensitivity analysis experiment of the impact of electromagnetic radiation on vegetation physiological indicators, when measuring the activity A of antioxidant enzymes, vegetation samples were collected and the activities of superoxide dismutase SOD, peroxidase POD, and catalase CAT were determined in the laboratory. A weighted comprehensive value was used, and the weights were determined according to the importance of each antioxidant enzyme in responding to electromagnetic radiation and saline-alkali stress damage.

[0040] ​When measuring the slope G, in addition to the conventional total station measurement of horizontal distance and vertical height difference calculation, multiple measurements are performed in different seasons (including rainy season and dry season) and under different precipitation conditions (such as light rain, rain, and after rain), and the current vegetation coverage V is recorded during each measurement. g 、The long-term average vegetation coverage V in the area g0 , measure the precipitation P in the previous period r And the average precipitation in the region over the same period over the past few years P r ( 0 ), according to the formula G′=G×(1+k 1 ×(V g -V g0 )+k 2 ×(P r -P r0 )) Corrected slope value, correction factor k 1 , k 2 Determined through field trials and data analysis.

[0041] Long-term vegetation restoration experiments were carried out in several bare soil test areas of typical transmission line tower foundations with different electromagnetic radiation intensities and micro-topography characteristics (including different combinations of slopes, slope directions and soil compactness). During the experiment, vegetation restoration related data such as vegetation coverage, vegetation type changes and vegetation height growth at different time points were regularly recorded. Correlation analysis was performed on these data with the corresponding electromagnetic radiation influence coefficient IE and micro-topography influence coefficient IT. Multiple nonlinear regression analysis was used to fit the relationship curve, and the index coefficient c was determined based on the curve fitting goodness of fit and the actual vegetation growth status. 1 、c 2 At the same time, the time factor t is introduced when calculating the vegetation restoration capacity evaluation index value V. According to the formula Calculate, c 1 (t), c 2 (t) is an exponential coefficient that changes with time, and its changing pattern is determined by analyzing and modeling long-term test data.

[0042] Before using the electromagnetic radiation spectrum analyzer, calibrate it with a standard electromagnetic radiation source at a known intensity and analyze the calibration error. During the measurement process, monitor the ambient temperature T and humidity H in real time. According to the formula E′=E×(1+m 1 ×(TT 0 )+m 2 ×(HH 0 )) Corrected measurement results, where E′ is the corrected electromagnetic radiation intensity, T 0 , H 0 The standard measurement environment temperature and humidity, m 1 、m 2 are the temperature and humidity correction factors, which are determined through previous calibration tests.

[0043] Microtopographic measuring instruments such as total stations, three-dimensional laser scanners and soil compaction stratification meters are calibrated and verified for accuracy regularly. The total station establishes a control network consisting of multiple reference points to measure the distance and angle deviation between reference points to evaluate the accuracy; the three-dimensional laser scanner uses a standard geometric model to verify the scanning accuracy; the soil compaction stratification meter is calibrated with standard soil samples of known compactness. When collecting vegetation samples, a stratified random sampling method is used according to the density of vegetation distribution (such as sparse vegetation areas and relatively dense vegetation areas) and terrain changes (such as low-lying areas and highlands). Sampling layers are set in different vegetation communities (such as salt-tolerant plant communities and ordinary plant communities) and terrain areas, and sampling points are randomly selected in each layer.

[0044] The collected electromagnetic radiation intensity data, micro-topography data and vegetation physiological index data were tested for outliers, and the 3σ principle (normal distribution data values ​​falling outside the mean ± 3 times the standard deviation were considered outliers) and the box plot method (data values ​​exceeding 1.5 times the interquartile range of the upper and lower quartiles were considered outliers). For the detected outliers, if the errors were caused by traceable reasons such as measuring instrument failure, sudden changes in the measuring environment (such as strong winds interfering with measuring instruments), etc., the data were corrected. If they were caused by special circumstances such as local geological anomalies (such as groundwater level fluctuations affecting soil properties) and short-term environmental interference (such as changes in soil moisture after heavy rainfall), the outliers were retained and marked and specially processed. For the electromagnetic radiation intensity data, logarithmic transformation was used for standardization, that is, E″=log(E+1), where E″ is the standardized electromagnetic radiation intensity. For the micro-topography data and vegetation physiological index data, a weighted standardization method was used according to the data range and correlation.

[0045] The preprocessed data are substituted into the quantitative model to calculate the vegetation restoration capacity evaluation index value V. The vegetation restoration capacity levels are divided according to the V value. In addition to the basic high, medium and low level divisions, more thresholds are introduced to divide the vegetation restoration capacity into multiple levels. Corresponding vegetation restoration strategy recommendations are formulated for different levels. For example, for high restoration capacity levels, measures such as optimizing the vegetation community structure and appropriately reducing maintenance interventions may be taken. For low restoration capacity levels, measures such as reselecting vegetation varieties that are more adaptable to the environment and improving soil salinity may be considered.

[0046] Effects brought about by this embodiment: Through the evaluation method of this embodiment, the bare soil vegetation restoration capacity of transmission line tower bases in coastal areas can be comprehensively and accurately evaluated, and factors such as electromagnetic radiation, special microtopography and soil salinization can be fully considered to provide a scientific basis for vegetation restoration work. Accurate evaluation results are helpful to reasonably select vegetation types and restoration measures, improve the survival rate and growth effect of vegetation in complex environments, enhance vegetation coverage in tower base areas, reduce the risk of soil erosion, ensure the stability of transmission line tower bases in marine climates and complex electromagnetic environments, and promote the gradual recovery and sustainable development of ecosystems. At the same time, this method also provides an effective reference example for the evaluation of bare soil vegetation restoration of transmission line tower bases in other similar special environments, and promotes the development and application of ecological protection technology for the entire transmission line.

[0047] Embodiment 2

[0048] The vegetation restoration capacity evaluation work was carried out in the bare soil area of ​​a transmission line tower base in a high-altitude area. This area has special climatic conditions such as low temperature, low oxygen, strong ultraviolet radiation and strong winds. The soil is relatively poor and the terrain is complex and changeable, which poses a huge challenge to vegetation growth and ecological restoration. At the same time, the electromagnetic environment around the tower base is affected by the high altitude and has certain particularities. This method is used to evaluate the vegetation restoration capacity.

[0049] Around the transmission line tower base, multiple monitoring circles (similar to concentric circles) are set up according to different altitudes and distances from the tower base. Monitoring points are arranged at specific angles in each circle. At each monitoring point, the electromagnetic radiation intensity E, the chlorophyll content C of vegetation leaves, the cell membrane permeability P and the antioxidant enzyme activity A are accurately measured. When calculating the electromagnetic radiation influence coefficient IE, the formula is strictly followed. Carry out, where C 0 , here G max , O max , S max and the weight coefficient b 1 、b 2 ,b,P 0 , A 0 ,C max , P max , A max And the weight coefficient a 1 、a 2 、a 3 、a 4 (Satisfy a 1 +a 2 +a 3 +a 4 =1) are determined through a large amount of preliminary high-altitude field research and laboratory analysis to accurately reflect the impact of electromagnetic radiation on vegetation in this special environment.

[0050] The slope G, slope direction O and soil compactness S of each point in the bare soil area of ​​the tower foundation are measured simultaneously, and the micro-topography influence coefficient IT is calculated. The formula is: (Satisfy b 1 +b 2 +b 3 =1) According to the research on high-altitude terrain characteristics and vegetation growth characteristics, since the angle and intensity of solar radiation in high-altitude areas vary greatly with the seasons, when converting the slope O into a numerical form, the changes in the solar altitude angle, azimuth angle and ultraviolet radiation intensity in different seasons and time periods are fully considered, and the effective solar radiation reception R is calculated in combination with a professional model. o , used to calculate the micro-topography influence coefficient IT.

[0051] After the soil compaction S is measured in layers, according to the formula (where q j is the depth d j The weight coefficient is 0 j <1, ) The weighted average soil compactness S′ is calculated, and the weight coefficient is determined according to the relationship between the root distribution of high-altitude vegetation and soil layers.

[0052] At each monitoring point, an electromagnetic radiation spectrum analyzer is used to analyze the 1 、f 2 , ..., f n At the same time, the electromagnetic radiation intensity E(f 1 )、E(f 2 )…、E(f n ), through the formula Calculate the comprehensive electromagnetic radiation intensity E, where the frequency band f i The weight coefficient w i (0 <w i <1, ) is determined based on a sensitivity experiment specifically targeting the effects of electromagnetic radiation on the physiological indicators of vegetation in high altitude areas, in order to more accurately evaluate the comprehensive impact of electromagnetic radiation on vegetation. When measuring the activity of antioxidant enzymes A, vegetation samples are collected and the activities of superoxide dismutase SOD, peroxidase POD, and catalase CAT are measured in the laboratory. The weighted comprehensive value is determined based on the importance of each enzyme in responding to the stress and damage of the special environment of high altitude (electromagnetic radiation, low temperature, low oxygen, strong ultraviolet rays, etc.), in order to comprehensively measure the antioxidant capacity of vegetation.

[0053] ​When measuring the slope G, the total station is used to measure the horizontal distance and vertical height difference to calculate the original slope value. Considering that precipitation in high-altitude areas is concentrated in a specific season and mostly exists in the form of snowfall, as well as the impact of strong winds on snow distribution and vegetation coverage, multiple measurements are performed in different seasons (such as snow accumulation season, snowmelt season, and growing season) and under different precipitation and snow cover conditions. The current vegetation coverage V is recorded for each measurement. g 、The average vegetation coverage of the region over the years V g0 , measure the precipitation (or snow accumulation) in the previous period of time P r And the average precipitation (or snow accumulation) in the region over the same period of many years P r0 According to the formula G′=G×(1+k 1 ×(V g -V g0 )+k 2 ×(P r -P r0 )) Corrected slope value, correction factor k 1 , k 2 It is obtained through high-altitude field experiments and data analysis to more accurately reflect the impact of slope on vegetation growth in complex environments.

[0054] Long-term vegetation restoration experiments were carried out in several bare soil test areas of typical high-altitude transmission line tower foundations with different electromagnetic radiation intensities, micro-topography characteristics (including different combinations of slopes, slope directions and soil compactness) and vegetation growth conditions. During the experiment, vegetation restoration-related data such as vegetation coverage, vegetation type changes, vegetation height growth and vegetation adaptation characteristics to low temperature and low oxygen environments (such as root growth depth, leaf morphology changes, etc.) at different time points were continuously recorded. These data were deeply correlated with the corresponding electromagnetic radiation influence coefficient IE and micro-topography influence coefficient IT. Multivariate nonlinear regression analysis was used to fit the relationship curve. The index coefficient c was determined by combining the curve fitting goodness, the actual vegetation growth performance in the special environment of high altitude and the evolution of the ecosystem. 1 、c 2 , the time factor t is introduced when calculating the vegetation restoration capacity evaluation index value V, according to the formula Calculate, where c 1 (t), c 2 (t) is an exponential coefficient that changes with time. Its changing pattern is determined through detailed analysis of long-term high-altitude test data and professional modeling to dynamically evaluate the vegetation restoration capacity.

[0055] Before using the electromagnetic radiation spectrum analyzer, use a standard electromagnetic radiation source to calibrate at a known intensity and carefully analyze the calibration error. During the measurement process, monitor the ambient temperature T, humidity H and air pressure P in real time (the air pressure in high altitude areas may affect the electromagnetic radiation measurement). According to the formula E′=E×(1+m1 ×(TT 0 )+m 2 ×(HH 0 )+m 3 ×(PP 0 )) Corrected measurement results (where E′ is the corrected electromagnetic radiation intensity, T 0 , H 0 , P 0 It is the standard measurement of ambient temperature, humidity and air pressure, m 1 、m 2 、m 3 is the corresponding correction factor, determined through preliminary calibration tests at high altitudes).

[0056] Microtopographic measuring instruments such as total stations, three-dimensional laser scanners and soil compaction stratification meters are calibrated and verified for accuracy regularly. The total station establishes a control network consisting of multiple high-altitude benchmark points to measure the distance and angle deviation between benchmark points to evaluate accuracy; the three-dimensional laser scanner uses standard geometric models specific to high-altitude areas to verify scanning accuracy; the soil compaction stratification meter is calibrated with high-altitude standard soil samples with known compactness; when collecting vegetation samples, a stratified random sampling method is used based on the distribution characteristics of high-altitude vegetation (such as the distribution of vegetation along the altitude gradient, the vertical stratification of vegetation communities, etc.) and complex terrain changes (such as valleys, ridges, slopes and other terrain parts). Sampling layers are set in different vegetation communities (such as cushion vegetation communities adapted to high-altitude cold environments, alpine meadow vegetation communities, etc.) and terrain areas, and sampling points are randomly selected in each layer to ensure that representative vegetation samples are collected.

[0057] The collected electromagnetic radiation intensity data, micro-topography data and vegetation physiological index data were tested for outliers. The 3σ principle (normal distribution data values ​​falling outside the mean ±3 times the standard deviation are considered outliers) and the box plot method (data values ​​exceeding 1.5 times the interquartile range of the upper and lower quartiles are considered outliers) were used. For the detected outliers, if the errors were caused by traceable reasons such as failure of the measuring instrument in a special environment at high altitude (such as low temperature causing performance changes of instrument components, changes in air pressure affecting measurement accuracy, etc.), sudden changes in the measurement environment (such as sudden strong winds, blizzards and other bad weather interfering with measurements), etc., the data were corrected. ; If there are special circumstances such as local geological anomalies (such as changes in soil properties caused by thawing of permafrost or frost heave in high altitude areas), short-term environmental disturbances (such as sharp changes in soil moisture during seasonal snowmelt, short-term fluctuations in vegetation physiological indicators caused by strong ultraviolet radiation, etc.), the outliers will be retained and marked and specially processed. For the electromagnetic radiation intensity data, logarithmic transformation and standardization are used, that is, E″=log(E+1), E″ is the standardized electromagnetic radiation intensity; for micro-topography data and vegetation physiological indicator data, weighted standardization methods are used according to the data range and correlation to improve data quality and ensure the accuracy of subsequent calculations and analysis.

[0058] The preprocessed data is substituted into the quantitative model to calculate the vegetation restoration capacity evaluation index value V. The vegetation restoration capacity levels are divided according to the V value. In addition to the conventional high, medium and low level divisions, more thresholds are introduced to divide the vegetation restoration capacity into multiple levels to more carefully reflect the vegetation restoration status. Vegetation restoration strategy recommendations that are highly adapted to high-altitude environments are formulated for different levels. For example, measures such as strengthening the maintenance of vegetation community stability and promoting natural succession of vegetation are adopted for high restoration capacity levels. For low restoration capacity levels, consideration is given to introducing vegetation varieties that are more cold-resistant, resistant to barrenness, and adaptable to strong ultraviolet radiation. At the same time, measures such as improving soil structure and increasing soil fertility are taken to enhance the vegetation restoration effect and promote the gradual recovery and stable development of the ecosystem in the bare soil area of ​​the transmission line tower base in high-altitude areas.

[0059] Effects brought by this embodiment: Through the evaluation method of this embodiment, the bare soil vegetation restoration capacity of the transmission line tower base in high-altitude areas can be comprehensively and accurately evaluated, and factors such as electromagnetic radiation, complex micro-topography, poor soil and severe climate in the special environment of high altitude can be fully considered, providing a highly targeted scientific basis for vegetation restoration work. Accurate evaluation results are helpful to reasonably screen vegetation types that adapt to high-altitude environments, formulate effective restoration measures, improve the survival rate and growth quality of vegetation in extreme environments, enhance vegetation coverage in the tower base area, reduce the risk of soil erosion and soil erosion, ensure the stability and safety of the transmission line tower base in high-altitude areas, and promote the healthy development of the ecosystem in high-altitude areas. At the same time, this method also provides a valuable reference example for the evaluation of bare soil vegetation restoration of transmission line tower bases in other similar special geographical environments, which is helpful to improve the application level of the entire transmission line ecological protection technology in complex environments.

[0060] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the same elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A comprehensive evaluation method for the vegetation restoration capacity of bare soil at the tower foundation of a transmission line, characterized in that: The steps of this method include: constructing an evaluation index system, constructing a quantification model, data collection, and calculation and grading; Construct an evaluation index system: Set concentric circles with radii r1, r2, and r3 centered on the tower base around the tower base of the transmission line, where r1 < r2 < r3. Set monitoring points at intervals of angle α on the concentric circles, and measure the electromagnetic radiation intensity E, the chlorophyll content C of the vegetation leaves, the cell membrane permeability P, and the antioxidant enzyme activity A. The coefficient IE affected by electromagnetic radiation is calculated according to the formula where C0, P0, and A0 are the average values of the chlorophyll content, cell membrane permeability, and antioxidant enzyme activity of the vegetation leaves in the normal environment, respectively, and C max , P max , A max are the maximum values of the chlorophyll content, cell membrane permeability, and antioxidant enzyme activity of the vegetation leaves under laboratory conditions, respectively. a1, a2, a3, and a4 are weight coefficients, and a1 + a2 + a3 + a4 = 1; Measure micro-topography related indicators, including measuring the slope G, slope direction O and soil compactness S of each point in the bare soil area of ​​the tower base. The micro-topography influence coefficient IT is calculated according to the formula Calculate, where G max , O max , S max are the slope, aspect and maximum soil compactness values ​​in the study area, b1, b2 and b3 are weight coefficients, and b1+b2+b3=1; Construct a quantitative model: define the vegetation restoration capacity evaluation index value as V, and the relationship between V and IE and IT is as follows: Where c1 and c2 are exponential coefficients, 0 <c1<1,0<c2<1; Data collection: Use a high-precision electromagnetic radiation spectrum analyzer to collect electromagnetic radiation intensity data around the tower base according to a predetermined grid layout. Use a total station, a three-dimensional laser scanner, and a soil compaction layer measuring instrument to collect micro-topography data. Collect vegetation samples of different types and growth stages according to the scientific stratified sampling method, and measure the leaf chlorophyll content, cell membrane permeability, and antioxidant enzyme activity in the laboratory; Calculation and grading: Substitute the collected data into the quantification model to calculate the vegetation restoration ability evaluation index value V. Divide the vegetation restoration ability level according to the V value. When V≥V1, it is a high restoration ability level. When V2<V<V1, it is a medium restoration ability level. When V≤V2, it is a low restoration ability level. V1 and V2 are thresholds.

2. The comprehensive evaluation method for vegetation restoration capacity of bare soil at the tower foundation of a power transmission line according to claim 1 is characterized in that: The measurement steps of the electromagnetic radiation intensity include: At each monitoring point, an electromagnetic radiation spectrum analyzer is used to detect the frequency bands f1, f2, ..., f n Simultaneously measure the electromagnetic radiation intensity E(f1), E(f2), ..., E(f n ), the comprehensive electromagnetic radiation intensity E is calculated according to the formula Calculate, where w i is the frequency band f i The weight coefficient is 0 <w i <1, w i Determined based on the sensitivity analysis experiment of the impact of electromagnetic radiation on vegetation physiological indicators; When measuring the antioxidant enzyme activity A, use the weighted comprehensive value of the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). The weights are determined according to the importance of each antioxidant enzyme in coping with electromagnetic radiation damage.

3. The comprehensive evaluation method for vegetation restoration capacity of bare soil at the tower foundation of a power transmission line according to claim 1 is characterized in that: The steps of measuring micro-topography related indicators include: when measuring the slope G, in addition to using a total station to measure the horizontal distance and vertical height difference calculation, multiple measurements are performed in different seasons and under different precipitation conditions, and after measurement, the formula G′=G×(1+k1×(V g -V g0 )+k2×(P r -P r0 )) correction, where V g is the vegetation coverage at the current measurement, V g0 is the average vegetation coverage of the region over the years, P r To measure the amount of precipitation in the previous period, P r0 is the average precipitation in the region over the same period over the years, and k1 and k2 are correction coefficients.

4. The comprehensive evaluation method for vegetation restoration capacity of bare soil at the tower foundation of a power transmission line according to claim 3 is characterized in that: The steps of measuring the micro-topography related indicators also include: When measuring the slope aspect O, the slope aspect is converted into numerical form, and the changes of solar altitude angle and azimuth angle in different seasons and at different times are considered. The effective solar radiation received by the slope aspect R is calculated by establishing a solar radiation model. o , R o Used for calculation of micro-topography influence coefficient IT; When measuring soil compaction S, at different depths d1, d2, ..., d m Layered measurement, weighted average soil compaction where q j is the depth d j The weight coefficient is 0 j <1, The weight coefficient is determined according to the importance of root distribution density and soil layer to vegetation growth.​ 5. The comprehensive evaluation method for vegetation restoration capacity of bare soil at the tower foundation of a power transmission line according to claim 1 is characterized in that: The steps of determining the index coefficient of the quantification model include: Conduct long-term vegetation restoration experiments in multiple typical transmission line tower base bare soil test areas with different electromagnetic radiation intensities and micro-topography characteristics. Record the vegetation restoration related data such as vegetation coverage, vegetation species change, and vegetation height growth at different time points. Conduct a correlation analysis between these data and the corresponding electromagnetic radiation influence coefficient IE and micro-topography influence coefficient IT. Fit the relationship curve through multiple non-linear regression analysis. Determine the index coefficients c1 and c2 according to the curve fitting goodness and the actual vegetation restoration situation; When calculating the vegetation restoration capacity evaluation index value V, the time factor t is introduced, and the formula is: c1(t) and c2(t) are exponential coefficients that change with time, and their changing patterns are determined by analyzing and modeling long-term test data.

6. The comprehensive evaluation method for bare soil vegetation restoration capacity of transmission line tower foundation according to claim 1 is characterized in that: The calibration steps of the data collection instrument include: When using the electromagnetic radiation spectrum analyzer, calibrate it with a standard electromagnetic radiation source at a known intensity, analyze the calibration error, and correct the measurement result according to the environmental temperature T and humidity H during the measurement according to the formula E′ = E×(1 + m1×(T - T0) + m2×(H - H0)), where E′ is the corrected electromagnetic radiation intensity, T0 and H0 are the standard measurement environmental temperature and humidity, and m1 and m2 are the temperature and humidity correction coefficients.

7. The comprehensive evaluation method for vegetation restoration capability of bare soil at the tower foundation of a power transmission line according to claim 5 is characterized in that: The calibration steps of the data collection instrument also include: Regular calibration and accuracy verification of the total station, three-dimensional laser scanner, and soil compaction layer measuring instrument. The total station evaluates the accuracy by measuring the distance and angle deviation between benchmark points through a control network composed of multiple benchmark points. The three-dimensional laser scanner verifies the scanning accuracy with a standard geometric model. The soil compaction layer measuring instrument is calibrated with a standard soil sample with a known compaction degree. When collecting vegetation samples, according to the density of vegetation distribution and terrain changes, use the stratified random sampling method to set sampling layers in different vegetation communities and terrain areas, and randomly select sampling points within each layer.

8. The comprehensive evaluation method for bare soil vegetation restoration capacity of transmission line tower foundation according to claim 1 is characterized in that: Before the calculation and grading step, there is also a data preprocessing step, which includes: The collected electromagnetic radiation intensity data, microtopography data and vegetation physiological index data were tested for outliers using the 3σ principle and box plot method. The 3σ principle states that normally distributed data values ​​outside the mean ±3 times the standard deviation are considered outliers. The box plot method states that data values ​​outside the 1.5 times interquartile range of the upper and lower quartiles are considered outliers. For detected outliers, if they are due to measurement errors and can be corrected retroactively, the data will be corrected. If they are due to special circumstances, the outliers will be retained and marked and specially processed. Measurement errors that can be corrected retroactively include instrument failures and sudden changes in the measurement environment. Special circumstances include local geological anomalies and short-term environmental interference. The electromagnetic radiation intensity data were normalized by logarithmic transformation, that is, E″=log(E+1), where E″ is the standardized electromagnetic radiation intensity. The micro-topography data and vegetation physiological index data were normalized by weighted method according to the data range and correlation.

9. The comprehensive evaluation method for bare soil vegetation restoration capacity of transmission line tower foundation according to claim 1 is characterized in that: In addition to dividing the vegetation restoration ability level into three levels of high, medium, and low by comparing the V value with V1 and V2, thresholds V3, V4, …, V are introduced. n-1 The vegetation restoration ability is divided into n levels, where V1 > V2 > V3 > … > V n-1 > V n , n > 3, and different vegetation restoration strategy suggestions are available for each level. The high restoration ability level V ≥ V1 is divided into high-excellent V ≥ V1 + ΔV1 and high-good V1 ≤ V < V1 + ΔV1, and the low restoration ability level V ≤ V2 is divided into low-poor V ≤ V2 - ΔV2 and low-extremely poor V2 - ΔV2 < V ≤ V2.

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