A differential treatment method for rocky desertification based on regional analysis

Abstract

The present invention discloses a differential treatment method for rocky desertification based on regional analysis, which relates to the technical field of environmental protection for rocky desertification treatment. It includes obtaining vegetation ecological image data of the rocky desertification area through remote sensing technology, obtaining vegetation images of the rocky desertification area in the form of mainly remote sensing images and supplemented by computer images, processing the vegetation images of the rocky desertification area to obtain processed vegetation images; obtaining meteorological data of the rocky desertification area, performing spatial interpolation through the inverse distance weighting method to obtain gridded meteorological data with a spatial resolution of 1 km × 1 km; constructing a drought monitoring model for the vegetation water index, vegetation water supply index, vegetation temperature index, and air temperature and vegetation drought index in the rocky desertification area through the processed vegetation images and the gridded meteorological data; the present invention evaluates the drought and vegetation conditions in the rocky desertification area through the vegetation coverage, the minimum water requirement threshold of the vegetation, and the suitable ecological water requirement threshold of the vegetation, improving the efficiency of rocky desertification treatment.

Description

Technical Field

[0001] The present invention relates to the technical field of rocky desertification control, and particularly to a differential control method for rocky desertification based on regional analysis. Background Art

[0002] The prior art (a patent for invention with the publication number of CN104737866B) discloses a method for controlling land rocky desertification. The present invention adopts the method of compounding geotextiles and geocells. On the one hand, it can be directly used for soil and water conservation in rocky desertification areas, creating conditions for large-scale afforestation. On the other hand, vegetation is planted in the geocells to reconstruct the ecosystem; it fixes stones and conserves water from the root source to prevent the expansion of rocky desertification. Implementing the present invention once can achieve good effects on the control of rocky desertification areas, effectively achieve soil and water conservation, effectively improve the conditions required for the growth of vegetation and shelter forests, effectively utilize the vast rocky desert resources in our country, and save the cost of controlling rocky desertified land. The prior art cannot evaluate the drought and vegetation conditions of rocky desertification areas through the vegetation coverage, the minimum water requirement threshold of vegetation, and the suitable ecological water requirement threshold of vegetation, cannot control the differences in rocky desertification through dynamic changes, and cannot improve the efficiency of controlling rocky desertification. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art; for this purpose, the present invention proposes a differential control method for rocky desertification based on regional analysis, which evaluates the drought and vegetation conditions of rocky desertification areas through the vegetation coverage, the minimum water requirement threshold of vegetation, and the suitable ecological water requirement threshold of vegetation, controls the differences in rocky desertification through dynamic changes, improves the efficiency of controlling rocky desertification, and solves the problem of environmental protection.

[0004] To achieve the above object, the first aspect of the present invention provides a differential control method for rocky desertification based on regional analysis, including obtaining vegetation ecological image data of a rocky desertification area through remote sensing technology, obtaining a vegetation image of the rocky desertification area in the form of mainly remote sensing images and supplemented by computer images, processing the vegetation image of the rocky desertification area to obtain a processed vegetation image;

[0005] Obtaining meteorological data of the rocky desertification area, performing spatial interpolation through the inverse distance weighting method to obtain grid meteorological data with a spatial resolution of 1 km × 1 km;

[0006] Constructing a drought monitoring model for the vegetation water index, vegetation water supply index, vegetation temperature index, and air temperature and vegetation drought index of the rocky desertification area through the processed vegetation image and the grid meteorological data;

[0007] Obtaining the minimum water requirement threshold of vegetation and the suitable ecological water requirement threshold of vegetation in the rocky desertification area through the drought monitoring model;

[0008] Obtain the vegetation coverage of the rocky desertification area based on the processed vegetation image;

[0009] Evaluate the rocky desertification area based on the minimum water requirement threshold of vegetation, the suitable ecological water requirement threshold of vegetation, and the vegetation coverage, and conduct differential treatment according to the evaluation results.

[0010] Preferably, the processing of the rocky desertification area vegetation image to obtain the processed vegetation image includes:

[0011] Use the rocky desertification area vegetation image as the basis for calibration processing, set the transmittance of the rocky desertification area vegetation image to a constant value, use a filter to denoise the image, obtain the projection speckle size information of the rocky desertification area vegetation image, and obtain the image correlation vector according to the projection speckle size information of the rocky desertification area vegetation image;

[0012] Calibrate the rocky desertification area vegetation image according to the image correlation vector, realize the correction and segmentation of the rocky desertification area vegetation image, divide it into vegetation and land, and obtain the processed vegetation image.

[0013] Preferably, the construction of the drought monitoring model for the rocky desertification area vegetation moisture index, vegetation water supply index, vegetation temperature index, air temperature and vegetation drought index through the processed vegetation image and grid meteorological data includes:

[0014] Calculate the vegetation moisture index, and the expression is:

[0015]

[0016] Among them, C represents the vegetation moisture index, E represents the actual evaporation of vegetation moisture, and P represents the potential evaporation of vegetation moisture;

[0017] Calculate the vegetation water supply index, and the expression is:

[0018]

[0019] Among them, V represents the vegetation water supply index, N represents the normalized vegetation index, and T c represents the vegetation canopy temperature;

[0020] Calculate the vegetation temperature index, air temperature and vegetation drought index, and the expression is:

[0021]

[0022] Among them, V t represents the vegetation temperature index, L represents the surface temperature, and L max represents the highest surface temperature corresponding to the normalized vegetation index, and L minDenoted as the lowest surface temperature corresponding to the normalized difference vegetation index, T v Denoted as air temperature and vegetation drought index.

[0023] Preferably, obtaining the minimum water requirement threshold of vegetation and the suitable ecological water requirement threshold of vegetation in the rocky desertification area through the drought monitoring model includes:

[0024] Set the reference vegetation evapotranspiration as ET o , K s is the water stress coefficient;

[0025] Calculate the vegetation water requirement quota by calculating the reference vegetation evapotranspiration and the water stress coefficient. The expression

[0026] is:

[0027] ET c = ET o ×K s ×N

[0028] Among them, ET c denotes the vegetation water requirement quota;

[0029] Obtain the minimum water requirement threshold of vegetation and the suitable ecological water requirement threshold of vegetation in the rocky desertification area according to the vegetation water requirement quota and the drought monitoring model. The expression is:

[0030]

[0031] Among them, ET min denotes the minimum water requirement threshold of vegetation, and ET copt denotes the suitable ecological water requirement threshold of vegetation.

[0032] Preferably, obtaining the vegetation coverage in the rocky desertification area according to the processed vegetation image includes:

[0033] Calculate the normalized difference vegetation index according to the processed vegetation image. The expression is:

[0034]

[0035] Among them, NIR denotes the near-infrared band, and R denotes the infrared wave;

[0036] Calculate the vegetation coverage according to the vertical projection area of the vegetation on the ground accounting for the total area of the rocky desertification area. The expression is:

[0037]

[0038] Among them, FVC denotes the vegetation coverage, and N veg denotes the N value of the pixel completely covered by vegetation, and N soilThe N value representing completely bare soil or uncovered pixels.

[0039] Preferably, evaluating the rocky desertification area according to the minimum water requirement threshold of vegetation, the suitable ecological water requirement threshold of vegetation and the vegetation coverage, and conducting differential treatment according to the evaluation results, including:

[0040] Establishing an evaluation criterion C according to the vegetation coverage n And the evaluation index set A m The evaluation index set A m Contains {a1,..., a nm} indicators;

[0041] Constructing an evaluation judgment matrix according to the dominance of the evaluation index set A m And obtaining the normalized sorting vector of the evaluation judgment matrix by the eigenvalue method, and conducting a consistency test on the normalized sorting vector to obtain the normalized eigenvector, and performing a weighted process on the normalized eigenvector to obtain the total weight W of the evaluation index;

[0042] Classifying and distinguishing the influencing factors of the vegetation coverage, and determining the factor set U and the evaluation set V according to the complexity of the vegetation coverage;

[0043] Conducting single-factor evaluation on each factor in the factor set U to confirm the membership degree of each factor to the evaluation set V, and obtaining the membership degree evaluation matrix R;

[0044] Calculating the final evaluation result according to the total weight W of the index and the membership degree evaluation matrix R, and the expression is:

[0045] Z = W * R

[0046] Where Z represents the final evaluation result;

[0047] The final evaluation result includes five levels: poor, relatively poor, average, good, and excellent;

[0048] If the actual minimum water requirement of vegetation and the actual suitable ecological water requirement of vegetation in the rocky desertification area are both greater than the minimum water requirement threshold of vegetation and the suitable ecological water requirement threshold of vegetation, then the rocky desertification area is dry;

[0049] If the actual minimum water requirement of vegetation and the actual suitable ecological water requirement of vegetation in the rocky desertification area are both less than the minimum water requirement threshold of vegetation and the suitable ecological water requirement threshold of vegetation, then the rocky desertification area is humid;

[0050] If the actual minimum water requirement of vegetation and the actual suitable ecological water requirement of vegetation in the rocky desertification area are both equal to the minimum water requirement threshold of vegetation and the suitable ecological water requirement threshold of vegetation, then the water level in the rocky desertification area is balanced;

[0051] Differentiated treatment is carried out according to the final evaluation results and the dynamic changes of the actual minimum water requirement of vegetation and the actual suitable ecological water requirement of vegetation in rocky desertification areas.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0053] The present invention evaluates the drought and vegetation conditions in rocky desertification areas through vegetation coverage, the minimum water requirement threshold of vegetation, and the suitable ecological water requirement threshold of vegetation, and improves the efficiency of rocky desertification treatment by addressing the differences in the dynamic changes of rocky desertification. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0055] Figure 1 It is a schematic flowchart of the method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0056] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0057] Please refer to Figure 1 , an embodiment of the first aspect of the present application provides a method for differentiated treatment of rocky desertification based on regional analysis, including obtaining vegetation ecological image data of a rocky desertification area through remote sensing technology, obtaining a vegetation image of the rocky desertification area in the form of mainly remote sensing images and supplemented by computer images, and processing the vegetation image of the rocky desertification area to obtain a processed vegetation image;

[0058] Further, the processing of the vegetation image of the rocky desertification area to obtain a processed vegetation image includes:

[0059] Taking the vegetation image of the rocky desertification area as the basis for calibration processing, setting the transmittance of the vegetation image of the rocky desertification area as a constant value, using a filter to denoise the image, obtaining the projection speckle size information of the vegetation image of the rocky desertification area, and obtaining an image correlation vector according to the projection speckle size information of the vegetation image of the rocky desertification area;

[0060] Calibrate the vegetation image of the rocky desertification area according to the image-related vector, realize the correction and segmentation of the vegetation image of the rocky desertification area, divide it into vegetation and land, and obtain the processed vegetation image.

[0061] It should be noted that in the embodiments of the present invention, the scanning frequency of the sensor carried by the airborne platform in the remote sensing technology is set to 100 kHz. The laser wavelength is in the near-infrared band. Before the UAV takes off, the flight route, flight altitude, flight speed, etc. are set in the route planning software. Since it is necessary to extract the vegetation information in the rocky desertification area to be studied, the cross-flight method is adopted, the flight altitude is set to 50 m, and the flight speed is set to 5 m / s. When obtaining data, the weather is clear, and a small amount of clouds are distributed at a high altitude, which has no impact on the data collected by the lidar.

[0062] Obtain the meteorological data of the rocky desertification area, perform spatial interpolation through the inverse distance weighting method, and obtain the gridded meteorological data with a spatial resolution of 1 km × 1 km;

[0063] Construct a drought monitoring model for the vegetation water index, vegetation water supply index, vegetation temperature index, air temperature and vegetation drought index in the rocky desertification area through the processed vegetation image and the gridded meteorological data;

[0064] Further, the construction of the drought monitoring model for the vegetation water index, vegetation water supply index, vegetation temperature index, air temperature and vegetation drought index in the rocky desertification area through the processed vegetation image and the gridded meteorological data includes:

[0065] Calculate the vegetation water index, and the expression is:

[0066]

[0067] Among them, C represents the vegetation water index, E represents the actual evaporation of vegetation water, and P represents the potential evaporation of vegetation water;

[0068] It should be noted that in the embodiments of the present invention, the vegetation water index is closely related to the physiological activities of vegetation. It is calculated based on the difference between the surface temperature of the crop and the air temperature, and its result has a better physical interpretability. Therefore, the present invention takes the vegetation water index as part of drought monitoring.

[0069] Calculate the vegetation water supply index, and the expression is:

[0070]

[0071] Among them, V represents the vegetation water supply index, N represents the normalized difference vegetation index, and T c represents the vegetation canopy temperature;

[0072] It should be noted that in the embodiments of the present invention, the vegetation water supply index is an index established based on the principle that when drought occurs, plants close their stomata, resulting in an increase in canopy temperature and hindering plant growth.

[0073] Calculate the vegetation temperature index, air temperature, and vegetation drought index, and the expression is:

[0074]

[0075] Among them, V t represents the vegetation temperature index, L represents the land surface temperature, and L max represents the highest land surface temperature corresponding to the normalized difference vegetation index, and L min represents the lowest land surface temperature corresponding to the normalized difference vegetation index, and T v represents the air temperature and vegetation drought index.

[0076] Obtain the minimum water requirement threshold and the suitable ecological water requirement threshold of vegetation in the rocky desertification area through the drought monitoring model;

[0077] Furthermore, the process of obtaining the minimum water requirement threshold and the suitable ecological water requirement threshold of vegetation in the rocky desertification area through the drought monitoring model includes:

[0078] Set the reference vegetation evapotranspiration as ET o , and K s is the water stress coefficient;

[0079] Calculate the vegetation water requirement quota by calculating the reference vegetation evapotranspiration and the water stress coefficient, and the expression

[0080] is:

[0081] ET c = ET o × K s × N

[0082] Among them, ET c represents the vegetation water requirement quota;

[0083] Obtain the minimum water requirement threshold and the suitable ecological water requirement threshold of vegetation in the rocky desertification area according to the vegetation water requirement quota and the drought monitoring model, and the expression is:

[0084]

[0085] Among them, ET min represents the minimum water requirement threshold of vegetation, and ET copt represents the suitable ecological water requirement threshold of vegetation.

[0086] Obtain the vegetation coverage of the rocky desertification area according to the processed vegetation image;

[0087] Further, obtaining the vegetation coverage degree of the rocky desertification area according to the processed vegetation image includes:

[0088] Calculating the normalized difference vegetation index according to the processed vegetation image, and the expression is:

[0089]

[0090] where NIR represents the near-infrared band and R represents the infrared band;

[0091] Calculating the vegetation coverage degree according to the vertical projection area of the vegetation on the ground accounting for the total area of the rocky desertification area, and the expression is:

[0092]

[0093] where FVC represents the vegetation coverage degree, N veg represents the N value of the pixel completely covered by vegetation, and N soil represents the N value of the pixel completely bare soil or without coverage.

[0094] Evaluating the rocky desertification area according to the vegetation minimum water requirement threshold, the vegetation suitable ecological water requirement threshold and the vegetation coverage degree, and carrying out differential treatment according to the evaluation result.

[0095] Further, evaluating the rocky desertification area according to the vegetation minimum water requirement threshold, the vegetation suitable ecological water requirement threshold and the vegetation coverage degree, and carrying out differential treatment according to the evaluation result includes:

[0096] Establishing an evaluation criterion C n and an evaluation index set A m , and the evaluation index set A m contains {a1,..., a nm} indicators;

[0097] Constructing an evaluation judgment matrix according to the dominance of the evaluation index set A m , obtaining the normalized sorting vector of the evaluation judgment matrix by the eigenvalue method, performing a consistency test on the normalized sorting vector to obtain a normalized eigenvector, and performing a weighted process on the normalized eigenvector to obtain the total weight W of the evaluation index;

[0098] Classifying and differentiating the influencing factors of the vegetation coverage, and determining a factor set U and an evaluation set V according to the complexity of the vegetation coverage;

[0099] Performing single-factor evaluation on each factor in the factor set U to confirm the membership degree of each factor to the evaluation set V, and obtaining a membership degree evaluation matrix R;

[0100] According to the total weight \(W\) of the indicators and the membership evaluation matrix \(R\), the final evaluation result is calculated, and the expression is:

[0101] \(Z = W\times R\)

[0102] where \(Z\) represents the final evaluation result;

[0103] The final evaluation result includes five levels: poor, relatively poor, average, good, and excellent;

[0104] If both the actual minimum water requirement of the vegetation in the rocky desertification area and the actual suitable ecological water requirement of the vegetation are greater than the minimum water requirement threshold of the vegetation and the suitable ecological water requirement threshold of the vegetation, then the rocky desertification area is arid;

[0105] If both the actual minimum water requirement of the vegetation in the rocky desertification area and the actual suitable ecological water requirement of the vegetation are less than the minimum water requirement threshold of the vegetation and the suitable ecological water requirement threshold of the vegetation, then the rocky desertification area is humid;

[0106] If both the actual minimum water requirement of the vegetation in the rocky desertification area and the actual suitable ecological water requirement of the vegetation are equal to the minimum water requirement threshold of the vegetation and the suitable ecological water requirement threshold of the vegetation, then the water level in the rocky desertification area is balanced;

[0107] Differentiated management is carried out according to the final evaluation result and the dynamic changes of the actual minimum water requirement of the vegetation and the actual suitable ecological water requirement in the rocky desertification area.

[0108] The above embodiments are only used to illustrate the technical method of the present invention and not to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical method of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A differential treatment method for rocky desertification based on regional analysis, characterized in that Including: Obtain the vegetation ecological image data of the rocky desertification area through remote sensing technology, obtain the vegetation images of the rocky desertification area in the form of mainly remote sensing images and supplemented by computer images, and process the vegetation images of the rocky desertification area to obtain the processed vegetation images; Obtain the meteorological data of the rocky desertification area, perform spatial interpolation through the inverse distance weighting method, and obtain the gridded meteorological data with a spatial resolution of 1 km × 1 km; Construct a drought monitoring model for the vegetation water index, vegetation water supply index, vegetation temperature index, air temperature and vegetation drought index of the rocky desertification area through the processed vegetation images and the gridded meteorological data; Obtain the minimum water requirement threshold and the suitable ecological water requirement threshold of the vegetation in the rocky desertification area through the drought monitoring model, including: Set the reference vegetation evapotranspiration as , is the water stress coefficient; Calculate the vegetation water requirement quota by calculating the reference vegetation evapotranspiration and the water stress coefficient, and the expression is: Among them, is expressed as the water requirement quota of vegetation, is expressed as the normalized difference vegetation index; Obtain the minimum water requirement threshold and the suitable ecological water requirement threshold of the vegetation in the rocky desertification area according to the vegetation water requirement quota and the drought monitoring model, and the expression is: Among them, is expressed as the minimum water requirement threshold of vegetation, is expressed as the suitable ecological water requirement threshold of vegetation, is expressed as the vegetation water index, is expressed as the vegetation water supply index, is expressed as the vegetation temperature index, is expressed as the air temperature and vegetation drought index; Obtain the vegetation coverage of the rocky desertification area according to the processed vegetation images; Evaluate the rocky desertification area according to the minimum water requirement threshold and the suitable ecological water requirement threshold of the vegetation and the vegetation coverage, and conduct differential treatment according to the evaluation results.

2. The differential treatment method for rocky desertification based on regional analysis according to claim 1, characterized in that, The processing of the vegetation images of the rocky desertification area to obtain the processed vegetation images includes: Take the vegetation images of the rocky desertification area as the basis for calibration processing, set the transmittance of the vegetation images of the rocky desertification area to a constant value, use a filter to denoise the images, obtain the projection speckle size information of the vegetation images of the rocky desertification area, and obtain the image correlation vector according to the projection speckle size information of the vegetation images of the rocky desertification area; Perform calibration processing on the vegetation images of the rocky desertification area according to the image correlation vector, realize the correction and segmentation of the vegetation images of the rocky desertification area, divide them into vegetation and land, and obtain the processed vegetation images.

3. A differential treatment method for rocky desertification based on regional analysis according to claim 1, characterized in that, The construction of a drought monitoring model for the vegetation water index, vegetation water supply index, vegetation temperature index, air temperature and vegetation drought index of the rocky desertification area through the processed vegetation images and the gridded meteorological data includes: Calculate the vegetation water index, and the expression is: Among them, is expressed as the vegetation moisture index, is expressed as the actual evapotranspiration of vegetation moisture, is expressed as the potential evapotranspiration of vegetation moisture; Calculate the vegetation water supply index, and the expression is: Among them, is expressed as the vegetation water supply index, is expressed as the normalized difference vegetation index, is expressed as the vegetation canopy temperature; Calculate the vegetation temperature index, air temperature and vegetation drought index, and the expression is: Among them, is expressed as the vegetation temperature index, is expressed as the land surface temperature, is expressed as the highest land surface temperature corresponding to the normalized difference vegetation index, is expressed as the lowest land surface temperature corresponding to the normalized difference vegetation index, is expressed as the air temperature and the vegetation drought index.

4. A differential treatment method for rocky desertification based on regional analysis according to claim 1, characterized in that, The obtaining of the vegetation coverage of the rocky desertification area according to the processed vegetation images includes: Calculate the normalized difference vegetation index according to the processed vegetation images, and the expression is: Among them, is represented as the near-infrared band, is represented as the infrared wave; Calculate the vegetation coverage according to the vertical projection area of the vegetation on the ground accounting for the total area of the rocky desertification area, and the expression is: Among them, is expressed as the vegetation coverage, is the value of the pixel completely covered by vegetation, value, is the value of the pixel that is completely bare soil or has no coverage. value.

5. A differential treatment method for rocky desertification based on regional analysis according to claim 1, characterized in that The evaluation of the rocky desertification area according to the minimum water requirement threshold and the suitable ecological water requirement threshold of the vegetation and the vegetation coverage, and the differential treatment according to the evaluation results include: Establish an evaluation criterion based on the vegetation coverage and the evaluation index set , the evaluation index set includes indicators; According to the evaluation index set Construct an evaluation judgment matrix based on the dominance degree, obtain the normalized sorting vector of the evaluation judgment matrix by the eigenvalue method, conduct a consistency test on the normalized sorting vector to obtain the normalized eigenvector, and perform a weighted process on the normalized eigenvector to obtain the total weight of the evaluation index ; Classify and distinguish the influencing factors of the vegetation cover, and determine the factor set according to the complexity of the vegetation cover and the evaluation set ; Perform single-factor evaluation on each factor in the factor set , and confirm the membership degrees of each factor to the evaluation set to obtain a membership-degree evaluation matrix ; According to the total weight of the indicators and the membership evaluation matrix , the final evaluation result is calculated, and the expression is: Among them, is expressed as the final evaluation result; The final evaluation results include five levels: poor, relatively poor, average, good, and excellent; If the actual minimum water requirement of the vegetation and the actual suitable ecological water requirement in the rocky desertification area are both greater than the minimum water requirement threshold and the suitable ecological water requirement threshold of the vegetation, then the rocky desertification area is drought-stricken; If both the actual minimum water requirement of the vegetation in the rocky desertification area and the actual suitable ecological water requirement of the vegetation are less than the vegetation minimum water requirement threshold and the vegetation suitable ecological water requirement threshold, the rocky desertification area is humid; If both the actual minimum water requirement of the vegetation in the rocky desertification area and the actual suitable ecological water requirement of the vegetation are equal to the vegetation minimum water requirement threshold and the vegetation suitable ecological water requirement threshold, the water level in the rocky desertification area is balanced; Differentiated management is carried out according to the final evaluation results and the dynamic changes of the actual minimum water requirement of the vegetation and the actual suitable ecological water requirement in the rocky desertification area.

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