CN106355334A - Farmland construction area determining method - Google Patents

Abstract

The invention relates to the field of farmland construction and land consolidation, in particular to a farmland construction area determining method. The method comprises steps of selecting a study area, and performing meshing, mesh unit encoding and data preprocessing on the study area; calculating judgment indexes of comprehensive quality of farmland in a mesh environment; performing normalization processing on the judgment indexes, and calculating and judging weights of the indexes relative to the comprehensive quality of the farmland; evaluating the comprehensive quality of the farmland with a multifactor comprehensive evaluation method, and dividing a high-standard farmland construction area with a natural discontinuity point grading method. Compared with the farmland construction area dividing method based on farmland map spots or administrative regions in the prior art, the farmland construction area determining method evaluates the farmland more scientifically and is more objective and obtains more accurate results through numerical evaluation based on the judgment indexes, high-standard farmland can be obtained through farmland construction, and the construction cost is reduced.

Description

Judgment method of farmland construction area

technical field

The invention relates to the fields of farmland construction and land improvement, in particular to a method for judging farmland construction areas, which classifies farmland construction and provides reference for subsequent construction of high-marked farmland.

Background technique

Building high-standard farmland is an important way to realize the protection of cultivated land from quantity protection to quantity and quality protection. Building high-standard farmland is an important way to transform traditional agriculture and develop modern agriculture, which is conducive to exerting organizational effects and realizing large-scale operations. Through the construction of high-standard farmland, the concentration and scale of cultivated land can be realized, and the problem of sporadic segmentation of cultivated land can be broken.

The construction of high-standard farmland should comprehensively consider various factors such as arable land production capacity, difficulty of land consolidation, and social and economic benefits. Therefore, on the one hand, the construction area should consider the local conditions of good cultivated land quality and concentrated and contiguous cultivated land, which are the internal factors for the construction of high-standard farmland; External factors, including the level of cultivated land infrastructure, location conditions, etc. However, in practice, local governments and land management departments are highly subjective in the construction of high-standard farmland, focusing on quantity rather than quality, and classify some fragmented, poor-quality, and difficult-to-renovate cultivated land as construction areas, resulting in the difficulty and cost of construction. It will be difficult to meet the basic requirements of high-standard farmland after completion. The evaluation system for arable land to be selected as a high-standard farmland construction area is still in the exploratory stage. The calculation of evaluation indicators is not objective and accurate enough, and the analysis is generally carried out with arable map spots or administrative districts as spatial units, which is not conducive to information retrieval and update. Therefore, how to scientifically and rationally delineate high-standard farmland construction areas is an important issue in the protection and construction of cultivated land.

Based on the above considerations and based on the basic principles and requirements of high-standard farmland construction, the present invention constructs an evaluation index system for county cultivated land to be selected as high-standard farmland construction areas, optimizes the index calculation method in a grid environment, comprehensively evaluates the quality of cultivated land, and then determines the high standard The spatial layout and timing arrangement of farmland construction provide support for high-standard farmland construction and land consolidation, and have broad application prospects and practical value.

Contents of the invention

(1) Technical problems to be solved

The purpose of the present invention is to provide a method for judging farmland construction areas by scientifically dividing county-level high-standard farmland construction areas and construction time sequences, so as to solve the problems of high subjectivity in existing farmland construction divisions, poor division quality, and increased farmland construction costs.

(2) Technical solution

In order to solve the above technical problems, the present invention provides a method for judging farmland construction areas, which includes:

Determine the study area and obtain the cultivated land quality data in the study area;

performing grid division on the research area, and establishing a spatial correspondence between grid units and the cultivated land quality data;

Construct the judgment index of the farmland construction area, and calculate the judgment index value corresponding to each grid unit;

The range normalization method is used to normalize the determination index value, and the analytic hierarchy process is used to determine the weight of the determination index relative to the comprehensive quality of cultivated land;

use Determine the comprehensive quality score of cultivated land, where A _i is the comprehensive quality score of cultivated land; n is the total number of judgment indicators; a _i is the score of the i-th judgment index; w _i is the weight of the i-th judgment index relative to the comprehensive quality of cultivated land;

Using the natural discontinuity point classification method, the farmland construction area is determined by the comprehensive quality score of the cultivated land, and the farmland construction area includes: a priority construction area, a general construction area and an unsuitable construction area.

Preferably, the cultivated land quality data includes: cultivated land county-level units, linear features and administrative area data, then

The step of dividing the research area into grids and establishing the spatial correspondence between grid units and the cultivated land quality data includes:

create grid;

Determine grid ownership based on administrative region data;

Grid coding is carried out according to grid ownership. Grid coding includes: provincial administrative division codes, prefectural administrative division codes, county administrative division codes, township administrative division codes, village administrative division codes, and grid unit sequence codes;

Connect the cultivated map spots and linear features to the grid, and superimpose the obtained grid with the cultivated land and linear features to obtain gridded cultivated map spots and linear features;

The area of cultivated land and the length of linear features in the grid unit are calculated according to the proportion of the intersecting part.

Preferably, the normalization process of the determination index value using the extreme difference normalization method, and the determination of the weight of the determination index relative to the comprehensive quality of the cultivated land by using the analytic hierarchy process include:

determining that the determination index is a positive index or an inverse index;

Normalization processing, when the judgment index is a positive index, the normalization calculation formula is: When the judgment index is an inverse index, the normalized calculation formula is: Among them, S _i is the normalized value of the i-th judging index; a _i is the actual value of the evaluation object of the i-th judging index; T _i is the evaluation critical value of the i-th judging index; A _i is the i-th index evaluation target value;

Establish a factor layer comparison matrix to determine the weight v _j of the factor layer relative to the target layer;

Establish the comparison matrix of the index layer, and determine the weight w _ij of the index layer relative to the factor layer;

Use w _i =v _j ·w _ij to determine the weight w _i of the index layer relative to the target layer, which can be regarded as the weight of judging the index relative to the comprehensive quality of cultivated land.

Preferably, the determination indicators include: natural index, cultivated land area ratio, field shape index, cultivated land concentration contiguous degree, ditch width, ditch density, field road width, field road density, farming distance, and influence degree of farmers' markets.

Preferably, the calculation method of the cultivated land natural index includes:

Using R _ij =α _ij ·C _Lij ·β _j , Calculate the natural equal index of the jth specified crop;

use Calculate the natural index of agricultural land of the i-th network unit;

Among them, C _Lij is the natural quality score of agricultural land of the jth specified crop in the i-th network unit; i is the number of the network unit; j is the number of the specified crop; k is the number of evaluation indicators; m is the number of evaluation indicators; w _k is The weight of the k-th evaluation index; f _ijk is the index score of the k-th evaluation index of the j-th specified crop in the i-th network unit, and the value is (0-100); R _ij is the i-th evaluation unit’s The natural index of the j specified crop; α _ij is the light temperature or climate production potential index of the j crop; β _j is the yield of the j crop;

The area weighted average method is used to calculate the average natural index of cultivated map spots in each grid unit, and the formula is as follows:

${\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; .</span>{\mathrm{<span\; class="notranslate">\; A</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}$

Among them, T _i is the weighted average of the cultivated land natural index in the i-th grid unit; S _ij is the area of the intersection of the j-th cultivated map patch and grid unit i in the i-th grid unit; A _ij is the The natural index of the cultivated land at the intersection of the jth cultivated map patch and grid unit i in the i grid unit.

Preferably, the calculation method of the cultivated land area ratio includes: using Calculate the cultivated land area ratio, where P _i is the cultivated land area ratio of the i-th grid unit; S is the area of the grid unit; a _ij is the area of the j-th cultivated patch in the i-th grid unit.

Preferably, the calculation of the field shape index includes:

Merge cultivated map spots whose spatial distance within the grid unit is less than the distance threshold;

use Calculate the field shape index, where FDI is the field shape index; A _i is the total area of cultivated land in the ith grid; L _i is the sum of the perimeter of the cultivated land in the i-th grid unit.

Preferably, the calculation of the concentrated contiguousness of cultivated land includes:

Determine the spatial distance between the cultivated fields, the area of the cultivated land and the mosaic elements of the farmland, the mosaic elements of the farmland include: field roads, ditches;

Determine the contiguous determination method, and determine whether two cultivated land plots are connected according to the contiguous determination method, the spatial distance and the farmland mosaic elements;

The contiguous judging method is: when the shortest spatial distance between two cultivated land plots is less than the distance threshold, it is determined that the two cultivated land plots are connected; when the spatial distance between the two cultivated land plots is greater than the distance threshold, and there is no When the farmland mosaic element is used, it is determined that the two cultivated fields are not connected; when there are only farmland mosaic elements between the two cultivated fields, it is determined that the two cultivated fields are connected;

Set the spatial weight according to the spatial distance between cultivated fields, and the spatial distance is inversely proportional to the spatial weight;

use Calculate the concentrated contiguousness of cultivated land, where IIC _i is the concentrated contiguousness of cultivated land, the larger the value is, the higher the degree of contiguousness is; n is the total number of cultivated land in the ith grid unit; a _l and a _k are respectively The area of the l-th and k-th cultivated land plots; W _lk is the spatial distance weight between the field l and the k-th plot, the value range is 0~1, and W _lk =1 when l and k are connected.

Preferably, the calculation method of the density of the ditch and the density of the field road is: Among them, P _i is the density of ditches or field roads in the i-th grid unit; L _ij is the length of the j-th road or ditch in the i-th grid unit intersecting with grid unit i; S _ij is the i-th The area of cultivated land at the intersection of the jth cultivated map patch and grid unit i in a grid unit.

Preferably, the calculation formulas of the width of the ditch and the width of the field road are: Among them, T _i is the weighted average value of the evaluation index in the i-th grid unit; S _ij is the length of the intersecting part of the j-th linear feature in the i-th grid unit and the grid unit i; A _ij is the i-th The index value of the intersection part of the jth linear feature in the grid unit and the grid unit i.

Preferably, the calculation method of the tillage distance is: Among them, T _i is the tillage distance of the i-th grid unit; A _ij is the area of the j-th cultivated patch in the i-th grid unit. S _ij is the distance between the center point of the jth farmland spot in the ith grid unit and the residential area to which it belongs.

Preferably, the formula for calculating the degree of influence of the farmer's market is: r=d _c /d, where F is the degree of influence of the farmers'market; M _i is the township scale index; dc is the actual distance between the township and the rural settlement, and _d is the influence radius of the township.

(3) Beneficial effects

The method for judging the farmland construction area provided by the present invention extracts the cultivated land quality data of the county, adopts the method of grid division, establishes the connection and corresponding relationship between the grid unit and the cultivated land quality data, and determines the judgment index for measuring the farmland construction situation, The numerical calculation of each grid unit is carried out through the determination index, and the scientific value for evaluating farmland construction is finally obtained after normalization and weight distribution. Compared with the method of dividing farmland construction areas by cultivated map spots or administrative regions in the prior art, the evaluation of farmland is more scientific, and the numerical evaluation by judging indicators is more objective and the result is more accurate. In the follow-up farmland construction, Construction costs are reduced.

Description of drawings

Fig. 1 is a schematic diagram of steps of a method for judging a farmland construction area in an embodiment of the present invention;

Fig. 2 is a schematic diagram of a grid unit encoding method in an embodiment of the present invention;

Fig. 3 is the spatial distribution diagram of the cultivated land natural quality in the research area in an embodiment of the present invention;

Fig. 4 is the spatial distribution diagram of the cultivated land spatial form score in the research area in one embodiment of the present invention;

Fig. 5 is the spatial distribution diagram of the cultivated land infrastructure score in the research area in one embodiment of the present invention;

Fig. 6 is the spatial distribution diagram of the cultivated land location condition score in the research area in one embodiment of the present invention;

Fig. 7 is a planning diagram of a high-standard farmland construction area in an embodiment of the present invention.

detailed description

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

Based on the fact that existing methods for judging farmland construction areas mostly use subjective judgments, and use the methods of cultivated map spots and administrative regions to divide, resulting in the problem of emphasizing quantity over quality and high cost of high-standard farmland construction, this invention provides a method for judging farmland construction areas .

The method for judging the farmland construction area, as shown in Figure 1, includes:

Step 110, determine the research area, and obtain the cultivated land quality data of the research area;

The research area generally selects the county range, and the cultivated land quality data is in the vector data format. Cultivated land quality data generally include cultivated land county-level units, linear features, and administrative division data. Strictly check the cultivated land quality data and other data, and eliminate outliers to ensure the reliability of the data.

Step 210, divide the research area into a grid, and establish the spatial correspondence between the grid unit and the cultivated land quality data;

This step is an important step for the grid environment to evaluate the comprehensive quality of cultivated land. Through this step, the cultivated land quality data is divided into grids to prepare for the calculation of the determination indicators corresponding to the subsequent grid units. This step is specifically expanded as:

Step 2110, create a grid;

Select a 1km×1km regular grid unit between the cultivated map spot and the administrative village scale, use the FishNet tool of ArcGIS to create a grid, set the size of the grid unit, and generate a 1km×1km grid;

It should be noted that the purpose of the present invention is to provide an idea and method for determining farmland construction areas. During the execution of the method, those skilled in the art can determine the grid size according to the specific research area. In this embodiment, a grid of 1 km×1 km is used. And, as the technology evolves, the tools used to create the mesh can adapt.

Step 2120, determine the grid ownership according to the administrative division data;

To determine the grid ownership is to determine the administrative region to which each grid unit belongs. Considering the small scale of the grid used, the grid ownership can be determined according to the ownership of the cultivated map spots, and the smallest unit of ownership is the administrative village.

Step 2130, perform grid coding according to grid ownership, grid coding includes: provincial administrative division code, city administrative division code, county administrative division code, township administrative division code, village administrative division code, grid unit sequence code ;

Since the grid ownership is set, the grid ownership needs to be reflected in the grid coding. As for the specific coding method of the grid coding, it can be determined according to the specific situation. The unit is given a unique location limit to facilitate the accuracy of location correspondence when determining the subsequent farmland construction area.

Next, Figure 2 provides an example of grid coding: 16-digit numbers are used to code the grid, followed by 2-digit provincial administrative division codes, 2-digit city administrative division codes, 2-digit county administrative division codes, and 3-digit administrative division codes. Township (town) administrative division code, 3-digit village administrative division code and 4-digit grid unit sequence code.

Step 2140, connect the cultivated map spots and linear features to the grid, and superimpose the obtained grid with the cultivated land and linear features to obtain gridded cultivated map spots and linear features;

In the ArcGIS software platform (in other embodiments, it can be replaced with other grid creation platforms), the cultivated map patch space is connected to the grid; The subsequent geometric intersection, that is, the gridded cultivated map patches and linear features.

Step 2150, calculate the cultivated land area and the length of the linear feature in the grid unit according to the proportion of the intersecting part.

The ratio of the intersecting parts is mainly the area ratio. This step is beneficial to the subsequent calculation of the grid area and the cultivated area of a certain product.

Step 310, constructing the judgment index of the farmland construction area, and calculating the judgment index value corresponding to each grid unit;

Judgment indicators are the key factors for judging high-standard farmland construction areas. The determination of judgment indicators generally takes into account the natural quality of cultivated land, the spatial form of cultivated land, the infrastructure of cultivated land, and the location conditions of cultivated land.

A. The natural quality index of cultivated land is generally represented by the natural index.

Using the natural quality data of cultivated land as the basic data of cultivated land quality, the natural quality of cultivated land can objectively reflect the quality of cultivated land under the influence of multiple factors such as regional light, temperature, climate, topographical conditions, and soil. In this technology, the natural index in the classification of agricultural land is used to represent the natural quality of cultivated land. Figure 3 shows distribution plots plotted against natural equal index scores. The specific determination steps are:

1) The weighted average method is used to calculate the natural quality score, and the calculation formula is:

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; L</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; m</span>}}{\mathrm{<span\; class="notranslate">\; w</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; .</span>{\mathrm{<span\; class="notranslate">\; f</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}\mathrm{<span\; class="notranslate">\; k</span>}}}{\mathrm{<span\; class="notranslate">\; 100</span>}}$

Among them, C _Lij is the natural quality score of agricultural land of the jth specified crop in the i-th network unit; i is the number of the network unit; j is the number of the specified crop; k is the number of evaluation indicators; m is the number of evaluation indicators; w _k is The weight of the k-th evaluation index; f _ijk is the index score of the k-th evaluation index of the j-th specified crop in the i-th network unit, and the value is (0-100).

2) Calculation formula of the natural index of the jth designated crop:

R _ij ＝α _ij ·C _Lij · _βj

Among them, R _ij is the natural index of the j-th designated crop in the i-th evaluation unit; α _ij is the light-temperature or climate production potential index of the j-th crop; β _j is the yield of the j-th crop.

3) Calculate the final natural quality of cultivated land according to the cooking system, and the formula for calculating the natural index is as follows:

Among them, R _i is the natural index of agricultural land (cultivated land) of the i-th grid unit.

In the subsequent normalization process, the average value of the quality iso-index is given here for the consistency of the statement. 4) The average natural iso-index of cultivated map patches in each grid unit is calculated by the area weighted average method, the formula as follows:

${\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; .</span>{\mathrm{<span\; class="notranslate">\; A</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}$

Among them, T _i is the weighted average of the cultivated land natural index in the i-th grid unit; S _ij is the area of the intersection of the j-th cultivated map patch and grid unit i in the i-th grid unit; A _ij is the The natural index of the cultivated land at the intersection of the jth cultivated map patch and grid unit i in the i grid unit.

B. Calculation of indicators of cultivated land spatial form

Highly marked farmland requires concentrated distribution of cultivated land, regular and contiguous fields. Therefore, this technology selects the cultivated land area ratio, field shape index and concentration contiguousness to reflect the spatial form of cultivated land. Figure 4 shows the distribution map drawn according to the spatial form score of cultivated land.

1) Ratio of cultivated land area

The calculation method of the cultivated land area ratio is: by matching the grid unit number and the gridded cultivated land number, calculate the sum of the cultivated land area within each grid unit, and copy the result to the cultivated land area field of the grid unit, to get The calculation result of the cultivated land area ratio indicator. The formula is as follows:

Among them, P _i is the cultivated land area ratio of the i-th grid unit; S is the area of the grid unit; a _ij is the area of the j-th cultivated patch in the i-th grid unit.

2) Field shape index

The regularity of the field can be reflected by the field shape index. The calculation of the field shape index involves the circumference of the cultivated land boundary. If the sum of the boundary circumferences of all cultivated patches is calculated, it cannot objectively reflect the spatial distribution of the cultivated land. Based on the above considerations, the present invention proposes a calculation strategy for the field shape index: if the cultivated land is adjacent in space, it will be merged; a certain distance threshold is set, and the cultivated map spots whose spatial distance is smaller than the distance threshold are merged and used as one overall. Finally, the following formula is used to calculate the field shape index:

$\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; D.</span>}\mathrm{<span\; class="notranslate">\; I</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; ln</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; ln</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; A</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span>}$

Among them, FDI is the field shape index; A _i is the total area of cultivated land in the i-th grid; L _i is the sum of the perimeter of the cultivated land in the i-th grid unit.

3) Concentration and contiguousness of cultivated land

In the grid unit, the factors that affect the concentration and contiguousness of cultivated land mainly include the spatial distance between plots (farmland blocks), the area of plots (farmland blocks), and the mosaic elements of farmland. Field roads and ditches and other farmland mosaic elements are agricultural critical infrastructure for production. Determine the contiguous determination method, and determine whether two cultivated land plots are connected according to the contiguous determination method, spatial distance, and farmland mosaic elements. The contiguous judging method is: when the shortest spatial distance between two cultivated fields is less than the distance threshold, it is determined that the two cultivated fields are connected; when the spatial distance between the two cultivated fields is greater than the distance threshold, and there is no farmland When mosaicking elements, it is determined that the two cultivated fields are not connected; when there are only farmland mosaic elements between the two cultivated fields, it is determined that the two cultivated fields are connected.

The spatial distance between plots should be the primary factor considered in the contiguous rule. When the shortest distance between two plots is less than a certain spatial distance (contiguous) threshold, the two are spatially connected; when When the distance between two plots is greater than the contiguous threshold and there is no farmland mosaic element between them, it is considered that the two cultivated lands are not connected; when there are only farmland mosaic elements such as field roads or ditches between the two cultivated land plots When , the two cultivated map patches are also considered to be connected during calculation. The spatial weight is set according to the distance between cultivated land blocks. The larger the distance is, the smaller the spatial weight is. When the cultivated land is contiguous, the spatial weight is equal to 1. The calculation formula of concentration contiguous degree is as follows:

${\mathrm{<span\; class="notranslate">\; IIC</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; l</span>}\mathrm{<span\; class="notranslate">\; k</span>}}}{{\mathrm{<span\; class="notranslate">\; S</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}$

Among them, IIC _i is the concentrated contiguous degree of cultivated land, the larger the value is, the higher the contiguous degree is; n is the total number of cultivated land plots in the i-th grid unit; a _l and a _k are the l-th and k-th cultivated lands respectively The area of the field; W _lk is the weight of the spatial distance between the field l and the field k, the value ranges from 0 to 1, and W _lk =1 when l and k are connected.

C. Calculation of indicators of cultivated land infrastructure

In the construction of high-standard farmland, ditches and field roads are the key construction objects as cultivated land infrastructure. This technology selects four cultivated land infrastructure indicators: ditch width, ditch density, field road width, and field road density. Figure 5 shows the distribution plotted for the cultivated land infrastructure score.

1) Ditch density and field road density

Both the ditch density and the field road density can be calculated using the following formula:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; l</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}$

Among them, P _i is the density of ditches or field roads in the i-th grid unit; L _ij is the length of the j-th road or ditch in the i-th grid unit intersecting with grid unit i; S _ij is the i-th The area of cultivated land at the intersection of the jth cultivated map spot and grid unit i in a grid unit;

2) Ditch width and field road width

Use the weighted average method to calculate the width of the ditch and the width of the field road, and use the following formula to calculate:

${\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; .</span>{\mathrm{<span\; class="notranslate">\; A</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}$

Among them, T _i is the weighted average value of the evaluation index in the i-th grid unit; S _ij is the length of the intersecting part of the j-th linear feature in the i-th grid unit and the grid unit i; A _ij is the i-th The index value of the intersection part of the jth linear feature in the grid unit and the grid unit i.

D. Calculation of location condition indicators of cultivated land

1) Distance from cultivated land

Cultivation distance refers to the distance from the cultivated land to the residential area to which it belongs. The smaller the cultivated distance is, the more it will save the time for farmers to travel between the residential area and the arable land, thereby improving the convenience of farming and the management level of the arable land. The calculation method is: calculate the distance from the center point of each cultivated map spot in the grid unit to the residential area to which it belongs, and then use the area weighted average method to calculate the cultivated distance of the grid unit. Calculated as follows:

${\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}<span\; class="notranslate">\; .</span>{\mathrm{<span\; class="notranslate">\; A</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}{{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}_{\mathrm{<span\; class="notranslate">\; j</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; j</span>}}}$

Among them, T _i is the tillage distance of the i-th grid unit; A _ij is the area of the j-th cultivated patch in the i-th grid unit. S _ij is the distance between the center point of the jth farmland spot in the ith grid unit and the residential area to which it belongs.

2) Influence of farmers' market

Farmer's market influence refers to the degree of influence of the farmer's market on the cultivated land. The closer the distance from the farmer's market to the farmer's market, the more conducive to the transportation of agricultural materials and the sale of agricultural products, so the economic benefits of the farmland are higher.

Townships were selected as the substitute data for farmers' markets, and the exponential decay method was used to calculate the impact of townships on cultivated land. Township data are simplified to point elements, and economic activities between rural settlements and townships are not affected by administrative ownership, but only related to the spatial distance between them. Therefore, referring to the Regulations on Grading Agricultural Land, the exponential decay method is used to calculate the impact of townships on residential areas. Each township has a maximum action distance. When a settlement is within its action distance, it will be affected by it. If a settlement is affected by multiple townships, the sum of the influence degrees of each township will be used as the impact of the farmer's market on the settlement. Spend. Townships can be divided into central towns, key towns and general towns, and townships of different levels have different influences. The specific calculation process of the farmer’s market influence is: calculate the distance from each rural residential area to the farmer’s market, calculate the influence degree of the farmer’s market on the rural residential area, and assign the result according to the ownership relationship between the grid and the rural residential area Give the grid to get the degree of impact of the farmer's market on the cultivated land. The specific formula is as follows:

$\mathrm{<span\; class="notranslate">\; f</span>}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}^{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; r</span>}}$

r=dc/ _d

Among them, F is the influence degree of the farmers'market; M _i is the township scale index; dc is the actual distance between the township and the rural residential area, and _d is the influence radius of the township. In this technology, the values of township scale index and influence radius refer to the following table:

Figure 6 shows the distribution map drawn according to the location condition score of cultivated land.

Step 410, normalize the judgment index value by adopting the range normalization method;

Since the measurement units of each evaluation index are inconsistent, a unified comprehensive evaluation model cannot be established among the original data, so it is necessary to normalize each evaluation index to achieve dimensionless. According to the characteristics of the constructed index system, adopt the corresponding normalization method to normalize all the indexes to 0-1. The present invention mainly adopts the range normalization method in the index normalization processing process, specifically includes:

Step 4110, determine whether the judgment index is a positive index or an inverse index;

Step 4120, perform normalization processing according to the positive index and the inverse index

When the judgment indicator is a positive indicator, the normalized calculation formula is: When the judgment index is an inverse index, the normalized calculation formula is: Among them, S _i is the normalized value of the i-th judging index; a _i is the actual value of the evaluation object of the i-th judging index; T _i is the evaluation critical value of the i-th judging index; A _i is the i-th index evaluation target value;

In practice, the average value of each evaluation object is usually used instead, or the lowest level value of the index in the evaluation object can be used instead; A _i is the evaluation target value of the i-th index, if there is no reference standard, expert A consultative approach determines the best choice for the target value, or substitutes the highest level of the indicator in each evaluation unit.

Step 510, using the AHP to determine the weight of the judgment index relative to the comprehensive quality of cultivated land;

In the comprehensive quality evaluation of cultivated land, the weight reflects the importance of the index relative to the target. The present invention uses Analytic Hierarchy Process (AHP) to determine the weight of the evaluation index in the delineation of the high-standard farmland construction area. The present invention first determines the weight of the factor layer relative to the target layer by establishing a factor layer comparison matrix, then establishes an index layer comparison matrix, determines the weight of the index layer relative to the factor layer, and finally determines the weight of the index layer relative to the target layer, thereby obtaining each evaluation The importance of indicators to the comprehensive quality of cultivated land. The formula is as follows:

w _i =v _j ·w _ij

Where w _i is the weight of the index layer relative to the target layer; v _j is the weight of the factor layer relative to the target layer; w _ij is the weight of the index layer relative to the factor layer.

Step 610, using Determining the Comprehensive Quality Score of Cultivated Land

Combined with the scores and weights of each indicator of the comprehensive quality of cultivated land, the multi-factor comprehensive evaluation method is used to calculate the comprehensive quality score of cultivated land. The formula is as follows:

${\mathrm{<span\; class="notranslate">\; A</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; w</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}$

Among them, A _i is the comprehensive quality score of cultivated land; n is the total number of judgment indicators; a _i is the score of the i-th judgment index; w _i is the weight of the i-th judgment index relative to the comprehensive quality of cultivated land;

Step 710, using the natural discontinuity point grading method to determine the farmland construction area according to the comprehensive quality score of the cultivated land.

To comprehensively evaluate the comprehensive quality of cultivated land in the study area, the comprehensive score is divided into three levels by using the natural discontinuity point classification method, and the high-standard farmland construction in the study area is divided into priority construction areas, general construction areas and unsuitable construction areas. Figure 7 shows the regional planning map for high-standard farmland construction.

The technical solution provided by this technology has the following beneficial effects: the method of grid division of the research area is adopted first, and the grid unit is used as the evaluation unit of the comprehensive quality of cultivated land, which solves the multi-scale problem in the calculation of evaluation indicators, and at the same time, facilitates data retrieval with updates. According to the basic requirements of high-standard farmland construction, 10 evaluation indicators are selected from four aspects of cultivated land natural quality, spatial form, infrastructure level and location conditions, and a comprehensive quality evaluation index system for cultivated land is constructed. In the grid environment, the area dominant Method, weighted average method and center point method, calculate the scores of each evaluation index and use the range method for normalization. The analytic hierarchy process is used to determine the weight of each evaluation index, and finally the multi-factor comprehensive evaluation method is used to calculate the comprehensive quality score of cultivated land, and the natural discontinuous classification method is used to sort and grade them, and then divide the high-standard farmland construction area and construction time sequence in the study area. The methods and technical solutions provided by this technology can provide support for county and high-standard farmland construction and land consolidation planning.

The measurement standards for high-standard farmland construction can refer to the "General Rules for High-standard Farmland Construction (GBT30600-2014)".

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (10)

1. A method for judging a farmland construction area, characterized in that it comprises: Determine the study area and obtain the cultivated land quality data in the study area; performing grid division on the research area, and establishing a spatial correspondence between grid units and the cultivated land quality data; Construct the judgment index of the farmland construction area, and calculate the judgment index value corresponding to each grid unit; The range normalization method is used to normalize the determination index value, and the analytic hierarchy process is used to determine the weight of the determination index relative to the comprehensive quality of cultivated land; use Determine the comprehensive quality score of cultivated land, where A _i is the comprehensive quality score of cultivated land; n is the total number of judgment indicators; a _i is the score of the i-th judgment index; w _i is the weight of the i-th judgment index relative to the comprehensive quality of cultivated land; Using the natural discontinuity point classification method, the farmland construction area is determined by the comprehensive quality score of the cultivated land, and the farmland construction area includes: a priority construction area, a general construction area and an unsuitable construction area. 2. The farmland construction area judgment method as claimed in claim 1, characterized in that, The cultivated land quality data includes: cultivated land counties and other units, linear features and administrative area data; but, The step of dividing the research area into grids and establishing the spatial correspondence between grid units and the cultivated land quality data includes: create grid; Determine grid ownership based on administrative region data; Grid coding is carried out according to grid ownership. Grid coding includes: provincial administrative division codes, prefectural administrative division codes, county administrative division codes, township administrative division codes, village administrative division codes, and grid unit sequence codes; Connect the cultivated map spots and linear features to the grid, and superimpose the obtained grid with the cultivated land and linear features to obtain gridded cultivated map spots and linear features; The area of cultivated land and the length of linear features in the grid unit are calculated according to the proportion of the intersecting part. 3. The method for judging farmland construction areas as claimed in claim 1, wherein said adopting the extreme difference normalization method carries out normalization processing to said judging index value, and utilizes AHP to determine judging index relative cultivated land Overall quality weighting, including: determining that the determination index is a positive index or an inverse index; Normalization processing, when the judgment index is a positive index, the normalization calculation formula is: When the judgment index is an inverse index, the normalized calculation formula is: Among them, S _i is the normalized value of the i-th judging index; a _i is the actual value of the evaluation object of the i-th judging index; T _i is the evaluation critical value of the i-th judging index; A _i is the i-th index evaluation target value; Establish a factor layer comparison matrix to determine the weight v _j of the factor layer relative to the target layer; Establish the comparison matrix of the index layer, and determine the weight w _ij of the index layer relative to the factor layer; Use w _i =v _j .w _ij to determine the weight w _i of the index layer relative to the target layer, which is regarded as the weight of judging the index relative to the comprehensive quality of cultivated land. 4. The method for judging farmland construction areas according to any one of claims 1-3, wherein the judging indicators include: natural index, cultivated land area ratio, field shape index, cultivated land concentration contiguousness, ditches Width, ditch density, field road width, field road density, farming distance, farmers' market influence. 5. The farmland construction area judgment method as claimed in claim 4, characterized in that, the calculation method of the cultivated land natural index comprises: Using R _ij =α _ij .C _Lij .β _j , Calculate the natural equal index of the jth specified crop; use Calculate the natural index of agricultural land of the i-th network unit; Among them, C _Lij is the natural quality score of agricultural land of the jth specified crop in the i-th network unit; i is the number of the network unit; j is the number of the specified crop; k is the number of evaluation indicators; m is the number of evaluation indicators; w _k is The weight of the k-th evaluation index; f _ijk is the index score of the k-th evaluation index of the j-th specified crop in the i-th network unit, and the value is (0-100); R _ij is the i-th evaluation unit’s The natural index of the j specified crop; α _ij is the light temperature or climate production potential index of the j crop; β _j is the yield of the j crop. 6. The method for judging farmland construction areas as claimed in claim 4, wherein the calculation method of the cultivated land area ratio comprises: using Calculate the cultivated land area ratio, where P _i is the cultivated land area ratio of the i-th grid unit; S is the area of the grid unit; a _ij is the area of the j-th cultivated patch in the i-th grid unit. 7. The farmland construction area judgment method as claimed in claim 4, wherein the calculation of the field shape index comprises: Merge cultivated map spots whose spatial distance within the grid unit is less than the distance threshold; use Calculate the field shape index, where FDI is the field shape index; A _i is the total area of cultivated land in the ith grid; L _i is the sum of the perimeter of the cultivated land in the i-th grid unit. 8. The method for judging farmland construction areas as claimed in claim 4, wherein the calculation of the concentrated contiguous degree of cultivated land comprises: Determine the spatial distance between the cultivated fields, the area of the cultivated land and the mosaic elements of the farmland, the mosaic elements of the farmland include: field roads, ditches; Determine the contiguous determination method, and determine whether two cultivated land plots are connected according to the contiguous determination method, the spatial distance and the farmland mosaic elements; Set the spatial weight according to the spatial distance between cultivated fields, and the spatial distance is inversely proportional to the spatial weight; use Calculate the concentrated contiguousness of cultivated land, where IIC _i is the concentrated contiguousness of cultivated land, the larger the value is, the higher the degree of contiguousness is; n is the total number of cultivated land in the ith grid unit; a _l and a _k are respectively The area of the l-th and k-th cultivated land plots; W _lk is the spatial distance weight between the field l and the k-th plot, the value range is 0~1, and W _lk =1 when l and k are connected. 9. The farmland construction area judgment method as claimed in claim 4, characterized in that, The calculation method of described ditch density, described field road density is: Among them, P _i is the density of ditches or field roads in the i-th grid unit; L _ij is the length of the j-th road or ditch in the i-th grid unit intersecting with grid unit i; S _ij is the i-th The area of cultivated land at the intersection of the jth cultivated map spot and grid unit i in a grid unit; and / or, The calculation formula of described ditch width, described field road width is: Among them, T _i is the weighted average value of the evaluation index in the i-th grid unit; S _ij is the length of the intersecting part of the j-th linear feature in the i-th grid unit and the grid unit i; A _ij is the i-th The index value of the intersection part of the jth linear feature in the grid unit and the grid unit i. 10. The farmland construction area judgment method as claimed in claim 4, characterized in that, The calculation method of the tillage distance is: Among them, T _i is the tillage distance of the i-th grid unit; A _ij is the area of the j-th cultivated patch in the i-th grid unit. S _ij is the distance between the center point of the jth cultivated map spot in the ith grid unit and the residential area to which it belongs; and / or, The formula for calculating the influence degree of the farmer’s market is: r=d _c /d, where F is the degree of influence of the farmers'market; M _i is the township scale index; d _c is the actual distance between the township and the rural settlement, and d is the influence radius of the township.