Cultivated land resource protection evaluation method and system

Abstract

The invention discloses a cultivated land resource protection evaluation method and system. The cultivated land resource protection evaluation method comprises the following steps: acquiring a multi-period remote sensing image of a research area; extracting land utilization data from the remote sensing image of each period of the research area, and generating vector diagram blocks of different land utilization types in the research area; on the basis of the land utilization data, land utilization quantity change data, cultivated land utilization dynamic attitude and a cultivated land quantity change intensity index of the research area are obtained through calculation; a cultivated land change index, a cultivated land quality index and a cultivated land ecological index of the research area are constructed; calculating weight values of the cultivated land change index, the cultivated land quality index and the cultivated land ecological index; and calculating a comprehensive evaluation value of cultivated land resource protection of the research area, wherein the comprehensive evaluation value is used for evaluating the cultivated land protection degree of the research area.

Description

Technical Field

[0001] The present invention relates to the technical field of land information analysis, and in particular to a method and system for evaluating the protection of cultivated land resources. Background Art

[0002] As an important part of land use types, cultivated land is the most valuable land resource. However, with the rapid development of my country's economy, the contradictions between my country's population, resources and environment have continued to increase sharply, and the cultivated land resource problems caused by this have become more prominent, and the cultivated land resource security issues have become more and more significant, mainly manifested in: 1. The amount of cultivated land continues to decrease; 2. The quality of cultivated land continues to decline; 3. The ecological environment of cultivated land continues to deteriorate.

[0003] Under the background of the rapid development of industrialization and urbanization, the rapid expansion of construction land and the rapid reduction of cultivated land are inevitable phenomena in the process of industrialization and urbanization. While the amount of cultivated land is decreasing, the quality of cultivated land resources has been reduced due to a series of problems such as the large-scale application of pesticides and fertilizers and the large-scale loss of water and soil, and ecological security is also threatened. The safe protection of cultivated land resources is related to food security, social stability and other aspects. In recent years, with the rapid development of urbanization in my country and the continuous improvement of people's living standards, the demand for transportation, industrial and mining, and construction land has also increased, which is bound to lead to the occupation of cultivated land resources and the security of cultivated land resources is seriously threatened. At the same time, we must give priority to the protection of cultivated land and ensure the realization of the task of protecting the amount of cultivated land and permanent basic farmland. The protection of cultivated land resources should coordinate the protection and utilization requirements of other types of natural resources such as forests, wetlands, and rivers, and should also be coordinated with the needs of urban construction.

[0004] Based on the above background, it is necessary to systematically evaluate the protection of regional arable land resources. Summary of the invention

[0005] In order to overcome the above technical defects, the present invention provides a method and system for evaluating the protection of cultivated land resources.

[0006] In order to solve the above problems, the present invention is implemented according to the following technical solutions:

[0007] In a first aspect, the present invention provides a method for evaluating the protection of cultivated land resources, comprising the following steps:

[0008] Obtain multiple remote sensing images of the study area;

[0009] Extract land use data from each period of remote sensing images of the study area and generate vector tiles of different land use types in the study area;

[0010] Based on the land use data, the land use quantity change data, the cultivated land use dynamics and the cultivated land quantity change intensity index of the study area are calculated;

[0011] Construct the cultivated land change index, cultivated land quality index and cultivated land ecological index in the study area;

[0012] Calculate the weight values ​​of cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators;

[0013] The comprehensive evaluation value of cultivated land resource protection in the study area is calculated, and the comprehensive evaluation value is used to evaluate the degree of cultivated land protection in the study area.

[0014] In combination with the first aspect, the present invention further provides a first specific implementation of the first aspect. Specifically, the calculation formula of the comprehensive evaluation value of cultivated land resource protection is:

[0015] Where, F is the comprehensive evaluation value of cultivated land resource protection, F∈[0,1], A(G i ) is the index value of the i-th index in the study area, W i is the weight of the ith indicator, and m represents the number of indicators.

[0016] In combination with the first aspect, the present invention further provides a second specific implementation of the first aspect, specifically, the cultivated land change index includes the permanent basic farmland area, the first changed land area, the third changed land area, the change intensity index of the cultivated land quantity and the dynamic degree of cultivated land utilization;

[0017] The said arable land quality indicators include soil organic matter content, soil texture, mechanical power per unit of arable land area and the proportion of arable land area with effective irrigation;

[0018] The ecological indicators of cultivated land include humidity index, forest coverage rate, water coverage rate, pesticide application per unit of cultivated land area, fertilizer application per unit of cultivated land area and industrial wastewater discharge compliance rate.

[0019] In combination with the first aspect, the present invention further provides a third specific implementation of the first aspect, specifically, obtaining multi-period remote sensing images of the study area specifically includes:

[0020] Obtain the first, second and third phase remote sensing data of the city in the study area, with the time interval between adjacent remote sensing data being 1, 2 or 3 years;

[0021] The first remote sensing data, the second remote sensing data and the third remote sensing data are cropped to obtain a first remote sensing image, a second remote sensing image and a third remote sensing image of the study area.

[0022] In combination with the first aspect, the present invention further provides a fourth specific implementation of the first aspect. Specifically, the construction of the cultivated land change index, cultivated land quality index and cultivated land ecological index of the study area specifically includes:

[0023] Min-Max standardization was performed on cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators;

[0024] The expression of the Min-Max normalization process is:

[0025] Where, X norm is the standard value of the ith indicator, X is the initial value of the ith indicator, and X min is the minimum value of the i-th index, X max is the maximum value of the i-th indicator.

[0026] In combination with the first aspect, the present invention further provides a fifth specific implementation manner of the first aspect, specifically, the land use types include cultivated land, forest land, grassland, water area, construction land and unused land.

[0027] In a second aspect, the present invention provides a system for evaluating the protection of cultivated land resources, comprising:

[0028] An acquisition module is used to acquire multi-period remote sensing images of the study area;

[0029] A generation module is used to extract land use data from each period of remote sensing images of the study area and generate vector tiles of different land use types in the study area;

[0030] A first calculation module is used to calculate the land use quantity change data, the dynamic degree of cultivated land use and the change intensity index of cultivated land quantity in the study area based on the land use data;

[0031] Construction module, which is used to construct the cultivated land change index, cultivated land quality index and cultivated land ecological index in the study area;

[0032] The second calculation module is used to calculate the weight values ​​of cultivated land change index, cultivated land quality index and cultivated land ecological index;

[0033] The third calculation module is used to calculate the comprehensive evaluation value of the protection of cultivated land resources in the study area, and the comprehensive evaluation value is used to evaluate the degree of cultivated land protection in the study area.

[0034] In combination with the second aspect, the present invention further provides a first specific implementation of the second aspect. Specifically, the calculation formula of the comprehensive evaluation value of cultivated land resource protection is:

[0035] Where, F is the comprehensive evaluation value of cultivated land resource protection, F∈[0,1], A(G i ) is the index value of the i-th index in the study area, W i is the weight of the ith indicator, and m represents the number of indicators.

[0036] In combination with the second aspect, the present invention further provides a second specific implementation of the second aspect, specifically, the cultivated land change index includes the permanent basic farmland area, the first changed land area, the third changed land area, the change intensity index of the cultivated land quantity and the dynamic degree of cultivated land utilization;

[0037] The said arable land quality indicators include soil organic matter content, soil texture, mechanical power per unit of arable land area and the proportion of arable land area with effective irrigation;

[0038] The ecological indicators of cultivated land include humidity index, forest coverage rate, water coverage rate, pesticide application per unit of cultivated land area, fertilizer application per unit of cultivated land area and industrial wastewater discharge compliance rate.

[0039] In combination with the second aspect, the present invention further provides a third specific implementation of the second aspect, specifically, the acquisition module acquires multi-period remote sensing images of the study area, specifically including:

[0040] Obtain the first, second and third phase remote sensing data of the city in the study area, with the time interval between adjacent remote sensing data being 1, 2 or 3 years;

[0041] The first remote sensing data, the second remote sensing data and the third remote sensing data are cropped to obtain a first remote sensing image, a second remote sensing image and a third remote sensing image of the study area.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The present invention provides a method for evaluating the protection of cultivated land resources, comprising the following steps: acquiring multi-period remote sensing images of a study area; extracting land use data from each period of remote sensing images of the study area, and generating vector blocks of different land use types in the study area; based on the land use data, calculating the land use quantity change data, cultivated land use dynamics and cultivated land quantity change intensity index of the study area; constructing cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators of the study area; calculating weight values ​​of cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators; and calculating a comprehensive evaluation value of cultivated land resource protection in the study area, wherein the comprehensive evaluation value is used to evaluate the degree of cultivated land protection in the study area.

[0044] The present invention evaluates the protection status of cultivated land resources through the analysis of multi-period remote sensing images and land use data, provides a reliable and effective cultivated land resource protection evaluation method, can determine the degree of protection of cultivated land resources in the study area, and can provide a scientific basis for relevant departments to make decisions and guide people's cultivated land use behavior. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings, wherein:

[0046] Figure 1 It is a schematic flow chart of a method for evaluating the protection of cultivated land resources of the present invention;

[0047] Figure 2 is a land use map of the land use data of the present invention;

[0048] Figure 3 It is a schematic diagram of the network structure of the encoding stage of the present invention;

[0049] Figure 4 It is a schematic diagram of the network structure of the decoding stage of the present invention;

[0050] Figure 5 It is a schematic diagram of the network structure in the fusion stage of the present invention. DETAILED DESCRIPTION

[0051] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0052] In the context of the rapid development of industrialization and urbanization, the rapid expansion of construction land and the rapid reduction of cultivated land are inevitable phenomena in the process of industrialization and urbanization. While the amount of cultivated land is decreasing, the quality of cultivated land resources has been reduced due to a series of problems such as the large-scale application of pesticides and fertilizers and the large-scale loss of water and soil, and ecological security has also been threatened. The safe protection of cultivated land resources is related to food security, social stability, and economic sustainable development. In recent years, with the rapid development of urbanization in my country and the continuous improvement of people's living standards, the demand for transportation, industry, mining, and construction land has also increased, which is bound to lead to the occupation of cultivated land resources and the safety of cultivated land resources is seriously threatened.

[0053] Based on the above background, it is necessary to systematically evaluate the protection of regional arable land resources.

[0054] refer to Figure 1The embodiment of the present invention provides a flow chart of a method for evaluating the protection of cultivated land resources. The present invention mainly evaluates the protection status of cultivated land resources through the analysis of multi-period remote sensing images and land use data, provides a reliable and effective method for evaluating the protection of cultivated land resources, can determine the degree of protection of cultivated land resources in the study area, and can provide a scientific basis for the decision-making of relevant departments and the guidance of people's cultivated land use behavior.

[0055] The farmland resource protection evaluation method of the present invention can be performed by a farmland resource protection evaluation system, which can be implemented in the form of hardware and / or software, and can be configured in an electronic device. Figure 1 As shown, the method includes:

[0056] S100: Acquire multi-period remote sensing images of the study area.

[0057] S200: Extract land use data from each period of remote sensing images of the study area and generate vector tiles of different land use types in the study area.

[0058] S300: Based on the land use data, the land use quantity change data, the cultivated land use dynamics and the cultivated land quantity change intensity index of the study area are calculated.

[0059] S400: Construct cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators in the study area.

[0060] S500: Calculate the weight values ​​of cultivated land change index, cultivated land quality index and cultivated land ecological index.

[0061] S600: Calculate a comprehensive evaluation value of cultivated land resource protection in a study area, where the comprehensive evaluation value is used to evaluate the degree of cultivated land protection in the study area.

[0062] The farmland resource protection evaluation of the present invention refers to building a reasonable evaluation index system based on the disclosure of the safe operation mechanism of farmland resources, combining the conditions of the research area, using appropriate evaluation models and methods, accurately evaluating the protection status of regional farmland resources, and proposing reasonable countermeasures and measures to ensure the smooth operation of the farmland resource system.

[0063] Specifically, this embodiment provides a detailed description of each step.

[0064] S100: Acquire multi-period remote sensing images of the study area.

[0065] In a specific implementation, obtaining a multi-period remote sensing image of the study area specifically includes obtaining a multi-period remote sensing image of the study area specifically including:

[0066] S110: Acquire the first phase remote sensing data, the second phase remote sensing data and the third phase remote sensing data of the city in the study area, where the time interval between adjacent remote sensing data is 1, 2 or 3 years.

[0067] In the present invention, among the first period remote sensing data, the second period remote sensing data and the third period remote sensing data, the third period remote sensing data is real-time remote sensing data, for example, it can be remote sensing data in 2024. For this reason, the second period remote sensing data is in 2022 and the first period remote sensing data is in 2020.

[0068] Specifically, the remote sensing data may be a Landsat satellite or a remote sensing image taken by a drone. In a specific implementation, the remote sensing data may be a multispectral satellite image of the study area (a panchromatic band with a spatial resolution of 2 meters and four multispectral bands with a spatial resolution of 8 meters).

[0069] S120: cropping the first period remote sensing data, the second period remote sensing data and the third period remote sensing data to obtain a first remote sensing image, a second remote sensing image and a third remote sensing image of the study area.

[0070] In a specific implementation, the irregular cropping of the study area is achieved through mask operation (Mask). The preset vector boundary map of the study area is used as a template for cropping. The vector boundary map of the study area is converted into img format in ERDAS. Then, through the mask operation (Mask) function in the Interpreter drop-down menu, the new value in the cropping area is set to 1, and the value outside the area is set to 0. The mask area is subjected to intersection operation (Intersection) to achieve irregular image cropping, and the remote sensing image of the study area is obtained.

[0071] In a preferred implementation, remote sensing image preprocessing is also included:

[0072] Because the remote sensing image formation process is affected by many different factors such as atmospheric radiation. In order to enhance the expression ability of the information contained in the remote sensing image and improve the accuracy of the information extracted from it, the initial remote sensing image needs to be preprocessed so that the remote sensing image is clear and the target object is more prominent.

[0073] The first step is to use the Mosaic Images function of ERDAS 9.2 software to mosaic the images. The three images are added through add image, and the image matching method is set to Overlap Areas. When stitching images, the grayscale calculation method of the pixels in the overlapping area is the average. By stitching images at different times, time series data can be formed.

[0074] The second step is to perform geometric correction. The image is corrected by multiple polynomial fitting methods, control points are selected, and the bilinear interpolation resampling method is used. After correction, the maximum error does not exceed one pixel. The specific operation is completed with the Geometric Correction function in ERDAS 9.2 software.

[0075] The third step is to perform radiation enhancement processing. Radiation enhancement processing is a remote sensing image processing method that aims to enhance the visual effect of the image by transforming the grayscale value of a single pixel. This method includes histogram matching, histogram stretching, strip noise removal, etc., with the aim of improving the visual effect and interpretability of remote sensing images. Radiation enhancement processing is mainly used in the remote sensing software ERDAS, which changes the image contrast by directly changing the pixel grayscale value of the image, thereby improving the image quality and observability.

[0076] S200: Extract land use data from each period of remote sensing images of the study area and generate vector tiles of different land use types in the study area.

[0077] In the present invention, the land use types include cultivated land, forest land, grassland, water area, construction land and unused land.

[0078] In a specific implementation, land use is divided into six categories: cultivated land, forest land, grassland, construction land, unused land and water area. The interpretation methods can be divided into two categories: manual visual interpretation and remote sensing automatic detection. Manual visual interpretation is the main means for people to extract various thematic information from remote sensing images. Remote sensing automatic classification can generally be divided into supervised classification and unsupervised classification.

[0079] By combining supervised classification with visual interpretation, land use information is extracted from the remote sensing images of the study area. The land use information includes land use type, the number of land use types, land use images (in the study area images), land use image boundaries, etc. Then, the remote sensing images of the study area are classified and recoded according to the land use information.

[0080] In another specific implementation, the present invention also provides different implementation schemes, the present invention uses a land use type classification network model (MSNet) for encoding, decoding and image fusion, obtains the final classification result, and outputs the land use type data of the study area, which is a land use type distribution map. The land use type distribution map includes multiple land use images (in the study area image), land use types, the number of land use types, land use image boundaries, etc.

[0081] Specifically, the present invention selects and calculates 6 channels as input data of a land use type classification network model (MSNet), which are 3 visible light bands of RGB, near infrared (NIR), normalized difference vegetation index (NDVI) and normalized difference water index (NDWI), and outputs the classification results.

[0082] Among them, the near-infrared band NIR obtains effective information when the visible light band is affected by different lighting conditions and causes information loss; NDVI can detect the growth status and coverage of vegetation, and play a role in eliminating some radiation errors in land use classification.

[0083] The calculation formula of vegetation normalization index is: Among them, X NDVI is the vegetation normalized index, X NIR Near infrared band, X R It is the red band.

[0084] Among them, the NDWI index can highlight the water body information in the image and can play a role in distinguishing water bodies in land use classification.

[0085] The calculation formula of NDWI index is: Among them, X NDWI is the normalized water index, X NIR is the near infrared band, X G It is the green band.

[0086] The land use type classification network model (MSNet) has a network structure of three stages: encoding, decoding, and fusion. The encoding stage is used to capture the deep features of the image; the decoding stage restores the details and spatial dimensions of the image; and the fusion stage fuses different features.

[0087] like Figure 2 , Figure 3 and Figure 4 As shown in the figure, the ResNet-50 network is used as the backbone network to encode the image information. ResNet-50 is a residual network that is widely used in the field of image processing. Through experiments, it is found that the use of convolution kernels with a size of 7×7, a number of 64, a step size of 2, and a padding of 3 in the convolution layer to extract features from the data has better results and higher extraction efficiency. The batch normalization operation (BN) is used to accelerate the convergence rate, and the Relu activation function helps the network learn nonlinear relationships and reduce the dimension of the feature map through the maximum pooling layer. The convolution layer set consisting of Conv2_x, Conv3_x, Conv4_x, and Conv5_x convolution layers is the backbone of ResNet-50. Each layer retains the encoding result, and e1, e2, e3, and e4 are obtained.

[0088] Specifically, to facilitate the decoding operation of the data, a decoding module is defined, with the input channel number C1 and the output channel number C2, and batch normalization, Relu function activation and upsampling are performed in sequence to restore the image resolution. There are 5 layers in the decoding stage. In the first layer, e5 is first passed through the decoding module to obtain a new feature map d5; in the next 4 layers, the feature map output by the decoding and the feature map retained in the encoding stage are spliced ​​according to dimension 1 to obtain the decoding results of d1, d2, d3, and d4. Through the design and optimization of the encoding stage, information loss can be minimized.

[0089] Specifically, a list of feature maps consisting of d1, d2, d3, and d4 is input, and convolution operations are performed on each of them to obtain f2, f3, and f4. The feature maps are upsampled using bilinear interpolation to keep the number of channels consistent. P1 is obtained by adding d1 to f2, P2 by adding f2 to f3, P3 by adding f3 to f4, and P4 is used alone as P4. A total of 4 feature maps are input into the image fusion module to obtain the final result. Through multi-layer feature fusion at the fusion layer, multi-level semantic information can be retained and fused, improving the quality and effect of image fusion.

[0090] It can be understood that the purpose is to obtain multiple tiles on the remote sensing image of the study area, each tile has land use information (cultivated land, forest land, grassland, construction land, unused land and water area), etc. In order to display the classification results in the form of a map, such as Figure 2 As shown in the figure, you can add legends, direction indicators and other map elements in ARCMAP. Convert the image of the study area containing land use information and map elements into vector data that can be edited in GIS.

[0091] S300: Based on the land use data, the land use quantity change data, the cultivated land use dynamics and the cultivated land quantity change intensity index of the study area are calculated.

[0092] In a specific implementation, the land use data obtained in step 200 is input into ARCGIS to obtain the land use quantity change data of the study area.

[0093] Statistics in ARCGIS can obtain the quantitative change data of land use in the study area, as shown in the following table. Using the spatial analysis module of ARCGIS, the conversion between various types of land use in the three phases of land use data can be analyzed.

[0094]

[0095] In a specific implementation, the land use change intensity index refers to the change of land use type j per unit area in a certain region from period a to period b. The calculation formula of the cultivated land change intensity index is as follows:

[0096] In the formula, LTI is the change intensity index of the number of cultivated land; TAb and TAa are the number of blocks of cultivated land in the study area in the first phase remote sensing images and the first phase remote sensing images, respectively; Lti is the total land area of ​​the study area; T is the time interval between TAb and TAa, calculated in years. The change area of ​​cultivated land and the change intensity index of cultivated land use in the study area can be obtained from the land use transformation data.

[0097] In a specific implementation, the land use dynamics can quantitatively describe the speed of change of a certain land use type in a certain area within a certain time range. The dynamic changes of cultivated land use types can be analyzed using the cultivated land use dynamics model to truly reflect the degree of change of cultivated land use types. The formula for the cultivated land use dynamics is:

[0098] In the formula, K is the dynamic degree of cultivated land use, TAa is the area of ​​cultivated land in the first period of remote sensing image data, TAb is the area of ​​cultivated land in the third period of remote sensing data, and T is the research time interval. If T is year, K is the annual change rate of cultivated land.

[0099] S400: Construct cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators in the study area.

[0100] In the present invention, there are two main factors that affect the quality of cultivated land resources: one is the natural resource endowment factor, and the other is the impact of cultivated land utilization methods on the quality of cultivated land resources. Natural resource endowment factors include the soil quality of the cultivated land, etc., and such factors are determined by innate natural conditions. In the process of cultivated land utilization, there is a widespread problem of heavy use of cultivated land and light maintenance, which is also the main factor threatening the quality of cultivated land resources. Incorrect cultivated land utilization methods will cause serious imbalance of cultivated land nutrients, soil impoverishment and other problems. The application of advanced science and technology to improve and drain cultivated land; the popularization and improvement of irrigation and drainage facilities, and the widespread use of agricultural machinery will greatly improve and enhance the quality of cultivated land resources.

[0101] The factors that affect the protection of cultivated land resources can be roughly divided into two categories: the first category is the factors that directly affect the cultivated land resource ecosystem, such as the large-scale application of pesticides and fertilizers will pollute the cultivated land ecosystem; the second category refers to the factors that produce indirect impacts, such as the improper discharge of industrial "three wastes" and domestic sewage. These factors first threaten the cultivated land resources and then indirectly affect the ecology of the cultivated land resources.

[0102] To this end, the cultivated land change indicators of the present invention include the permanent basic farmland area, the first change land area, the third change land area, the change intensity index of the cultivated land quantity and the dynamic degree of cultivated land utilization. The cultivated land quality indicators include soil organic matter content, soil texture, mechanical power per unit cultivated land area and the proportion of effectively irrigated cultivated land area. The cultivated land ecological indicators include humidity index, forest coverage rate, water coverage rate, pesticide application per unit cultivated land area, fertilizer application per unit cultivated land area and industrial wastewater discharge compliance rate.

[0103] In the present invention, humidity index: reflects the impact of precipitation and temperature on the ecological security of cultivated land, and the calculation formula is humidity index = annual precipitation / (annual average + 5). Forest coverage rate: reflects the ecological environment of cultivated land resources. The larger the value, the greater the vegetation coverage, indicating that the ecological security of cultivated land resources is higher. Industrial wastewater discharge compliance rate: can reflect the amount of wastewater carried by regional cultivated land. The higher the wastewater discharge compliance rate, the lower the threat to the ecological security of cultivated land resources.

[0104] The forest coverage rate can be obtained by dividing the total area of ​​forest tiles in the land use data by the total area of ​​the study area, and the water coverage rate can be obtained by dividing the total area of ​​water tiles by the total area of ​​the study area.

[0105] Furthermore, the cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators of the study area are constructed, including:

[0106] Min-Max standardization was performed on cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators;

[0107] The expression of the Min-Max normalization process is:

[0108] Where, X norm is the standard value of the ith indicator, X is the initial value of the ith indicator, and X min is the minimum value of the i-th index, X max is the maximum value of the i-th indicator.

[0109] S500: Calculate the weight values ​​of cultivated land change index, cultivated land quality index and cultivated land ecological index.

[0110] In a specific implementation, the evaluation index system for farmland resource protection is as follows:

[0111]

[0112]

[0113] Specifically, the analytic hierarchy process (AHP) is used to determine the indicator weights. The analytic hierarchy process is a common technique. In order to avoid affecting the evaluation results, the entropy method can also be used to determine the indicator weights.

[0114] In one example, the following are the general steps for determining weights using the AHP method:

[0115] 1. Determine the indicator system

[0116] The above-mentioned evaluation index system for farmland resource protection is adopted.

[0117] 2. Construct a judgment matrix

[0118] For each pair of indicators, a pairwise comparison is conducted and a relative importance score is assigned based on expert experience or relevant data. The commonly used scale is an integer representation of 1-9.

[0119] For example: Compare the cultivated land change index with the cultivated land quality index: If the cultivated land change is more important than the cultivated land quality, assign a value of 3; otherwise, assign a value of 1. Compare the cultivated land quality index with the cultivated land ecological index: If the two are equally important, assign a value of 1.

[0120] 3. Calculate feature vectors and weights

[0121] The judgment matrix is ​​normalized and the weight value of each indicator, that is, the corresponding eigenvector, is calculated.

[0122] 4.Consistency test

[0123] The construction of the judgment matrix may be inconsistent, and a consistency test (CI and CR) is required. If the consistency is passed, the weight is valid, otherwise the judgment matrix needs to be adjusted.

[0124] 5. Calculate the final weight

[0125] After the above steps, the weight values ​​of cultivated land change, cultivated land quality and cultivated land ecological indicators are finally obtained.

[0126] 6. Use entropy method for comparison

[0127] In order to avoid the evaluation results being affected by human subjectivity, the entropy method can also be used to calculate the weights. The entropy method is an objective weighting method that reflects the amount of information of the indicator by calculating the information entropy of each indicator, thereby determining the weight. By comparing the results of the analytic hierarchy process with the entropy method, a more comprehensive and objective indicator weight can be obtained. In this way, by combining the results of the analytic hierarchy process and the entropy method, the deviation caused by a single method can be effectively avoided, thereby obtaining a more reliable evaluation result.

[0128] S600: Calculate a comprehensive evaluation value of cultivated land resource protection in a study area, where the comprehensive evaluation value is used to evaluate the degree of cultivated land protection in the study area.

[0129] In a specific implementation, the calculation formula of the comprehensive evaluation value of cultivated land resource protection is:

[0130]

[0131] Where, F is the comprehensive evaluation value of cultivated land resource protection, F∈[0,1], A(G i ) is the index value of the i-th index in the study area, W i is the weight of the ith indicator, and m represents the number of indicators.

[0132] In a specific implementation, the farmland resource protection levels are classified into the following standards:

[0133]

[0134] The present invention also provides a farmland resource protection evaluation system for executing and realizing the above-mentioned farmland resource protection evaluation method. The farmland resource protection evaluation system includes:

[0135] An acquisition module is used to acquire multi-period remote sensing images of the study area;

[0136] A generation module is used to extract land use data from each period of remote sensing images of the study area and generate vector tiles of different land use types in the study area;

[0137] A first calculation module is used to calculate the land use quantity change data, the dynamic degree of cultivated land use and the change intensity index of cultivated land quantity in the study area based on the land use data;

[0138] Construction module, which is used to construct the cultivated land change index, cultivated land quality index and cultivated land ecological index in the study area;

[0139] The second calculation module is used to calculate the weight values ​​of cultivated land change index, cultivated land quality index and cultivated land ecological index;

[0140] The third calculation module is used to calculate the comprehensive evaluation value of the protection of cultivated land resources in the study area, and the comprehensive evaluation value is used to evaluate the degree of cultivated land protection in the study area.

[0141] In the present invention, the calculation formula of the comprehensive evaluation value of cultivated land resource protection is:

[0142] Where, F is the comprehensive evaluation value of cultivated land resource protection, F∈[0,1], A(G i) is the index value of the i-th index in the study area, W i is the weight of the ith indicator, and m represents the number of indicators.

[0143] In the present invention, the cultivated land change index includes permanent basic farmland area, first change land area, third change land area, change intensity index of cultivated land quantity and dynamic degree of cultivated land utilization;

[0144] The said arable land quality indicators include soil organic matter content, soil texture, mechanical power per unit of arable land area and the proportion of arable land area with effective irrigation;

[0145] The ecological indicators of cultivated land include humidity index, forest coverage rate, water coverage rate, pesticide application per unit of cultivated land area, fertilizer application per unit of cultivated land area and industrial wastewater discharge compliance rate.

[0146] In the present invention, the acquisition module acquires multiple remote sensing images of the study area, specifically including:

[0147] Obtain the first, second and third phase remote sensing data of the city in the study area, with the time interval between adjacent remote sensing data being 1, 2 or 3 years;

[0148] The first remote sensing data, the second remote sensing data and the third remote sensing data are cropped to obtain a first remote sensing image, a second remote sensing image and a third remote sensing image of the study area.

[0149] For other structures of the method and system for evaluating and protecting cultivated land resources described in this embodiment, refer to the prior art.

[0150] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Therefore, any modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for evaluating the protection of cultivated land resources, characterized in that: The following steps are involved: Obtain multiple remote sensing images of the study area; Extract land use data from each period of remote sensing images of the study area and generate vector tiles of different land use types in the study area; Based on the land use data, the land use quantity change data, the cultivated land use dynamics and the cultivated land quantity change intensity index of the study area are calculated; Construct the cultivated land change index, cultivated land quality index and cultivated land ecological index in the study area; Calculate the weight values ​​of cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators; The comprehensive evaluation value of cultivated land resource protection in the study area is calculated, and the comprehensive evaluation value is used to evaluate the degree of cultivated land protection in the study area.

2. A method for evaluating cultivated land resource protection according to claim 1, characterized in that: The calculation formula of the comprehensive evaluation value of cultivated land resource protection is: Where, F is the comprehensive evaluation value of cultivated land resource protection, F∈[0,1], A(G i ) is the index value of the i-th index in the study area, W i is the weight of the ith indicator, and m represents the number of indicators.

3. A method for evaluating the protection of cultivated land resources according to claim 2, characterized in that: The cultivated land change indicators include permanent basic farmland area, first change land area, third change land area, change intensity index of cultivated land quantity and dynamic degree of cultivated land use; The said arable land quality indicators include soil organic matter content, soil texture, mechanical power per unit of arable land area and the proportion of arable land area with effective irrigation; The ecological indicators of cultivated land include humidity index, forest coverage rate, water coverage rate, pesticide application per unit of cultivated land area, fertilizer application per unit of cultivated land area and industrial wastewater discharge compliance rate.

4. A method for evaluating cultivated land resource protection according to claim 1, characterized in that: The step of obtaining multi-period remote sensing images of the study area specifically includes: Obtain the first, second and third phase remote sensing data of the city in the study area, with the time interval between adjacent remote sensing data being 1, 2 or 3 years; The first remote sensing data, the second remote sensing data and the third remote sensing data are cropped to obtain a first remote sensing image, a second remote sensing image and a third remote sensing image of the study area.

5. The method for evaluating the protection of cultivated land resources according to claim 1, characterized in that: The cultivated land change index, cultivated land quality index and cultivated land ecological index of the research area specifically include: Min-Max standardization was performed on cultivated land change indicators, cultivated land quality indicators and cultivated land ecological indicators; The expression of the Min-Max normalization process is: In the formula, X norm is the standard value of the ith indicator, X is the initial value of the ith indicator, and X min is the minimum value of the i-th index, X max is the maximum value of the i-th indicator.

6. A method for evaluating the protection of cultivated land resources according to claim 1, characterized in that: The land use types include cultivated land, forest land, grassland, water area, construction land and unused land.

7. A system for evaluating the protection of cultivated land resources, characterized in that: include: An acquisition module is used to acquire multi-period remote sensing images of the study area; A generation module is used to extract land use data from each period of remote sensing images of the study area and generate vector tiles of different land use types in the study area; A first calculation module is used to calculate the land use quantity change data, the cultivated land use dynamics and the change intensity index of the cultivated land quantity in the study area based on the land use data; Construction module, which is used to construct the cultivated land change index, cultivated land quality index and cultivated land ecological index in the study area; The second calculation module is used to calculate the weight values ​​of cultivated land change index, cultivated land quality index and cultivated land ecological index; The third calculation module is used to calculate the comprehensive evaluation value of the protection of cultivated land resources in the study area, and the comprehensive evaluation value is used to evaluate the degree of cultivated land protection in the study area.

8. The system for evaluating the protection of cultivated land resources according to claim 7 is characterized in that: The calculation formula of the comprehensive evaluation value of cultivated land resource protection is: Where, F is the comprehensive evaluation value of cultivated land resource protection, F∈[0,1], A(G i ) is the index value of the i-th index in the study area, W i is the weight of the ith indicator, and m represents the number of indicators.

9. A farmland resource protection evaluation system according to claim 8, characterized in that: The cultivated land change indicators include permanent basic farmland area, first change land area, third change land area, change intensity index of cultivated land quantity and dynamic degree of cultivated land use; The said arable land quality indicators include soil organic matter content, soil texture, mechanical power per unit of arable land area and the proportion of arable land area with effective irrigation; The ecological indicators of cultivated land include humidity index, forest coverage rate, water coverage rate, pesticide application per unit of cultivated land area, fertilizer application per unit of cultivated land area and industrial wastewater discharge compliance rate.

10. The system for evaluating the protection of cultivated land resources according to claim 7, characterized in that: The acquisition module acquires multiple remote sensing images of the study area, specifically including: Obtain the first, second and third phase remote sensing data of the city in the study area, with the time interval between adjacent remote sensing data being 1, 2 or 3 years; The first remote sensing data, the second remote sensing data and the third remote sensing data are cropped to obtain a first remote sensing image, a second remote sensing image and a third remote sensing image of the study area.

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