Multi-scale hilly farmland slope division method and system

Abstract

The present invention provides a multi-scale hilly farmland slope position division method and system, the method comprising: determining the spatial variation of soil moisture at the regional macro scale and the field local scale according to the soil moisture distribution of the target hilly farmland, and further determining the variation scale; dividing the target hilly farmland area according to the regional macro and field local variation scales according to TPI and corresponding thresholds, and obtaining the primary slope position and the secondary slope position; obtaining the fine slope position division result of the target hilly farmland area according to the combination of the primary slope position and the secondary slope position. The multi-scale hilly farmland slope position division method and system provided by the present invention, based on the terrain position index with scale effect, uses different scales to divide the slope position and combines the slope positions of two different scales to form the hilly farmland fine slope position division result, which can more accurately reflect the actual terrain characteristics and express the specific soil moisture migration process, and is easy to operate and relatively small in calculation.

Description

Technical Field

[0001] The present invention relates to the field of farmland terrain division, and in particular to a multi-scale hilly farmland slope division method and system. Background Art

[0002] Landform is a general term for various undulating forms on the earth's surface, which drives many surface processes. Quantitative analysis of landform is an important data basis for multiple disciplines such as agronomy, soil science, meteorology, spatial hydrology, geography, geomorphology, and ecology. Topographic position, also known as slope position, is an important indicator for describing topographic and geomorphic characteristics. It consists of spatially adjacent units with similar topographic characteristics at a certain scale. Slope position division is an important part of quantitative analysis of landform. On natural slopes, different slope positions (such as valleys, ridges, etc.) often show different geographical and hydrological processes due to different geomorphic characteristics of each part. Therefore, slope position information is of great significance to the fields of digital soil mapping, hydrological modeling, natural habitat analysis, and simulation of geographical ecological processes.

[0003] Slope position is an important factor affecting the spatial variation of soil moisture and nutrients in farmland. Slope position is one of the key factors to focus on when formulating agricultural management measures. Topography, especially local slope, is an important factor affecting the spatial difference of soil moisture in farmland. There is often a difference in soil moisture within and between plots in farmland, which is closely related to slope position. However, at present, digital elevation model geometric parameters or hydrological analysis methods are mainly used to divide slope position, which has a large amount of calculation and cannot fully reflect the difference in terrain expression at the regional macro scale and the local scale of the field. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a multi-scale hilly farmland slope division method and system.

[0005] The present invention provides a multi-scale hilly farmland slope position division method, comprising: determining the spatial variation of soil moisture at a regional macro scale and a field local scale according to the soil moisture distribution of a target hilly farmland area, so as to determine the regional macro and field local variation scales; dividing the target hilly farmland area according to a terrain position index TPI based on the regional macro and field local variation scales respectively, so as to obtain a primary slope position and a secondary slope position; and obtaining a fine slope position division result of the target hilly farmland area according to a combination of the primary slope position and the secondary slope position.

[0006] According to a multi-scale hilly farmland slope division method of an embodiment of the present invention, the spatial variation of soil moisture at the regional macro scale and the local scale of the field is determined according to the soil moisture distribution of the target hilly farmland area to determine the regional macro and local scale of the field, including: determining the semi-variance function of soil moisture values ​​at different scales at the regional macro scale and the local scale of the field according to the soil moisture distribution; and determining the variation scale sizes of the regional macro scale and the local scale of the field according to the range of the semi-variance function.

[0007] According to a multi-scale hilly farmland slope division method of an embodiment of the present invention, the semi-variance functions of soil moisture values ​​at different scales at regional macro-scale and field local scale are determined according to soil moisture distribution, including:

[0008]

[0009] Among them, γ(h) is the semivariogram function; Z(X i ) is the soil moisture value corresponding to the pixel, Z(X i+h ) is the soil moisture value corresponding to another pixel with a step size of h; h is the step size, and N(h) is the number of pixel logarithms with a step size of h.

[0010] According to a multi-scale hilly farmland slope position division method of an embodiment of the present invention, the target hilly farmland area is divided according to the terrain position index TPI based on the regional macro and local variation scales of the field to obtain the primary slope position and the secondary slope position, including: according to the regional macro and local variation scales of the field, according to the ratio of TPI to SD, and the corresponding threshold value, the target hilly farmland area is divided to obtain the primary slope position, and each field is divided to obtain the secondary slope position; wherein SD is the standard deviation value of TPI and the elevation of the neighboring pixel.

[0011] According to a multi-scale hilly farmland slope position division method of an embodiment of the present invention, a fine slope position division result of a target hilly farmland area is obtained according to a combination of a primary slope position and a secondary slope position, including: obtaining a corresponding first slope position index according to the primary slope position division; obtaining a corresponding second slope position index according to the secondary slope position division; multiplying the first slope position index by 10, and performing a weighted summation with the second slope position index to obtain a fine slope position index of the target hilly farmland area.

[0012] According to a multi-scale hilly farmland slope division method of one embodiment of the present invention, after obtaining the fine slope division result of the target hilly farmland area, it also includes: determining the distribution pattern of soil moisture or soil nutrients in the target hilly farmland area according to the slope division result.

[0013] According to a multi-scale hilly farmland slope division method according to an embodiment of the present invention, after determining the distribution pattern of soil moisture or soil nutrients in the target hilly farmland area based on the slope division results, it also includes: predicting the soil moisture values ​​of all other slopes based on the soil moisture values ​​measured at some slopes and the distribution pattern of the soil moisture.

[0014] The present invention also provides a multi-scale hilly farmland slope position division system, comprising: a scale determination module, used to determine the spatial variation of soil moisture at the regional macro scale and the field local scale according to the soil moisture distribution of the target hilly farmland area, so as to determine the regional macro and field local variation scales; a slope position division module, used to divide the target hilly farmland area according to the regional macro and field local variation scales according to the terrain position index TPI, and obtain the primary slope position and the secondary slope position; a slope position combination module, used to obtain the fine slope position division result of the target hilly farmland area according to the combination of the primary slope position and the secondary slope position.

[0015] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the multi-scale hilly farmland slope division method as described in any one of the above are implemented.

[0016] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the multi-scale hilly farmland slope division methods described above.

[0017] The multi-scale hilly farmland slope division method and system provided by the present invention is based on a terrain position index with scale effect, uses different scales to divide the slopes and combines two slopes of different sizes to form a hilly farmland fine slope division result, which can more accurately reflect the actual terrain characteristics and express the specific soil moisture migration process, and is easy to operate and relatively small in calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is one of the flow diagrams of the multi-scale hilly farmland slope division method provided by the present invention;

[0020] Figure 2It is a schematic diagram of the soil moisture semivariance function curve provided by the present invention;

[0021] Figure 3 It is a schematic diagram of semivariogram data collection based on remote sensing images provided by the present invention;

[0022] Figure 4 This is the second flow chart of the multi-scale hilly farmland slope division method provided by the present invention;

[0023] Figure 5 It is a cross-sectional curve diagram of different slope position division methods provided by the present invention;

[0024] Figure 6 It is a distribution diagram of soil moisture on slopes of different scales provided by the present invention;

[0025] Figure 7 It is a system submenu diagram provided by the present invention;

[0026] Figure 8 It is the main interface of the system and the scale calculation diagram provided by the present invention;

[0027] Fig. 9 It is a structural schematic diagram of a multi-scale hilly farmland slope position division system provided by the present invention;

[0028] Fig.10 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Combine the following Figure 1-Figure 10 The present invention describes a multi-scale hilly farmland slope division method and system. Figure 1 This is one of the flow charts of the multi-scale hilly farmland slope division method provided by the present invention, such as Figure 1 As shown, the present invention provides a multi-scale hilly farmland slope division method, including:

[0031] 101. Based on the soil moisture distribution in the target hilly farmland area, determine the spatial variation of soil moisture at the regional macro scale and the local scale of the field, so as to determine the regional macro and local variation scales.

[0032] The present invention divides the target hilly farmland area into slope positions, and the soil moisture value distribution can be obtained based on the soil moisture inversion grid data. For example, the inversion grid data with a pixel size of 12.5m. The present invention performs scale estimation based on soil moisture data. Since the terrain position index contains a scale effect, the neighborhood size of a certain point used in the calculation can use the semivariogram function to calculate the effective range size of the spatial autocorrelation of soil moisture in the target area, which is used as the different scales when calculating TPI. In particular, the present invention obtains spatial variation from two scales. On the one hand, the variation of moisture distribution is determined from the entire area, that is, the target hilly farmland area to be analyzed, and the macroscopic variation scale is determined; on the other hand, the variation of moisture distribution is determined from the field or plot scale, and the local scale of the field is determined.

[0033] 102. The target hilly farmland area is divided according to the terrain position index TPI based on the regional macro and field local variation scales to obtain the first-level slope position and the second-level slope position.

[0034] For example, the regional macroscale and field local scale, where the spatial variability of soil moisture is obvious, are 3000m and 300m, respectively.

[0035] Based on the above scales calculated according to soil moisture, slope positions can be divided into two scales. The large scale (regional macroscale) is 3000m, and this scale (neighborhood size) is used to divide the large-scale slope type of a certain point; the small scale (field local scale) is 300m, and the small-scale (local scale) slope position of a certain point is divided.

[0036] 103. Based on the combination of the primary slope and the secondary slope, the fine slope division result of the target hilly farmland area is obtained.

[0037] For example, the first-level slope is divided into 5 levels of slopes at a scale of 3000m, and in multiple fields, the second-level slopes are divided into 6 levels at a scale of 300m. The combination of the two can get up to 30 slope levels.

[0038] The multi-scale slope position division result of the present invention can be used as an important topographic factor representation, and can be used as an important factor in establishing a soil moisture regression model and a key covariate for soil moisture spatial interpolation based on sample points.

[0039] The multi-scale hilly farmland slope division method provided by the present invention is based on a terrain position index containing scale effects. It uses different scales to divide the slopes and combines two slopes of different sizes to form a fine slope division result of hilly farmland. It can more accurately reflect the actual terrain characteristics and express the specific soil moisture migration process, and it is easy to operate and relatively small in calculation.

[0040] In one embodiment, based on the soil moisture distribution in the target hilly farmland area, the spatial variation of soil moisture at the regional macro scale and the local scale of the field is determined to determine the regional macro and local scale variation scales, including: based on the soil moisture distribution, determining the semi-variance functions of soil moisture values ​​at different scales at the regional macro scale and the local scale of the field; based on the range of the semi-variance function, determining the variation scale sizes of the regional macro scale and the local scale of the field.

[0041] like Figure 2 As stated, Figure 2 The scale unit in is the number of pixels. According to the semivariogram function curve, the effective range of soil moisture in the study area and typical plots is 250 and 25 pixels, respectively, and the scale size is about 3000m and 300m.

[0042] In one embodiment, determining the semi-variance functions of soil moisture values ​​at different scales at the regional macro scale and the field local scale according to the soil moisture distribution includes:

[0043]

[0044] Among them, γ(h) is the semivariogram function; Z(X i ) is the soil moisture value corresponding to the pixel, Z(X i+h ) is the soil moisture value corresponding to another pixel with a step size of h; h is the step size, and N(h) is the number of pixel logarithms with a step size of h.

[0045] like Figure 3 As shown, X i is a pixel, and h is the step size of the pixel.

[0046] In one embodiment, the target hilly farmland area is divided according to the terrain position index TPI based on the regional macro and local variation scales to obtain the primary slope position and the secondary slope position, including: the target hilly farmland area is divided according to the regional macro and local variation scales, according to the ratio of TPI to SD, and the corresponding threshold value to obtain the primary slope position, and each field is divided to obtain the secondary slope position; wherein SD is the standard deviation value of TPI and the elevation of the neighboring pixel.

[0047] Specifically, according to DEM, the target hilly farmland area is divided into the first-level slope position, and each field is divided into the second-level slope position. Among them, DEM is as follows.

[0048] The target hilly farmland area is divided according to TPI, and also includes, according to DEM and the set threshold, combining the slope and the slope threshold, dividing the target hilly farmland area into the first-level slope position, and dividing each field into the second-level slope position.

[0049] The present invention is divided according to the DEV value, which is formed on the basis of the terrain position index (TPI), and is specifically calculated as follows:

[0050]

[0051]

[0052] Among them, Z0 represents the center point elevation, R represents the preset neighborhood, and Z i represents the elevation in the neighborhood, and n represents the number of elevation points in the neighborhood.

[0053] As an optional embodiment, the specific threshold conditions when using DEV to divide the slope position based on different scales are shown in Table 1-Table 2. For the convenience of typesetting below, the TPI and SD of DEV are listed separately at both ends of the inequality sign.

[0054] Table 1 Regional macro-scale slope classification thresholds

[0055]

[0056]

[0057] Table 2 Slope classification thresholds at the local scale of fields

[0058] serial number type Threshold 1 Valley TPI2<-1.0SD 2 Downhill position -1.0SD <TPI2<-0.5SD 3 Flat slope -0.5SD<TPI2<0.3SD,Slope<3° 4 Mid-slope -0.5SD <TPI2<0.3SD,Slope> 3° 5 Uphill position <h2 style=";text-align:left;direction:ltr">0.3SD <TPI2<1SD <h2 style=";text-align:left;direction:ltr"> 6 Ridge TPI2>1.0SD

[0059] Note: SD represents the standard deviation of TPI and the neighboring pixel elevation, and Slope represents the slope.

[0060] In one embodiment, a fine slope position division result of a target hilly farmland area is obtained according to a combination of a primary slope position and a secondary slope position, including: obtaining a corresponding first slope position index according to the primary slope position division; obtaining a corresponding second slope position index according to the secondary slope position division; multiplying the first slope position by 10, and performing a weighted summation with the second slope position index to obtain a fine slope position index of the target hilly farmland area, that is, a target slope position index under dual scales.

[0061] For details, please refer to the above table. 1-5 in Table 1 is the first slope index, and 1-6 in Table 2 is the second slope index. Since the multiple of the first scale to the second scale is 10. Based on the above two types of slope positions, a new slope category is formed by superimposing, or called a slope index. The large-scale slope type is multiplied by 10 and added to the type on the small-scale slope to form a double-scale slope type code. For example, 11 represents a depression in a valley, and 12 represents a downhill slope in a valley.

[0062] In one embodiment, after obtaining the fine slope division result of the target hilly farmland area, the method further includes: determining the distribution pattern of soil moisture or soil nutrients in the target hilly farmland area according to the slope division result.

[0063] Figure 4 This is the second flow chart of the multi-scale hilly farmland slope division method provided by the present invention, such as Figure 4 As shown, according to the detailed division results of the slope position, the soil moisture distribution law can be accurately analyzed. Compared with the existing slope position division method, the present invention can accurately analyze the soil moisture distribution law. Specifically, according to the slope position division results, the distribution law of soil moisture or soil nutrients in the target hilly farmland area at other times can be determined.

[0064] The profile line of the study area is used to reflect the difference between the slope position and the actual terrain changes. Figure 5 The actual profile curves of the two sample areas A and B and the corresponding macro-regional scale slope positions, local scale slope positions of fields and multi-scale combined slope positions are displayed. The multi-scale combined slope positions are similar to the overall terrain changes and can show more detailed information. More characteristic points of the actual terrain can be identified, which correspond to the peaks and valleys in the actual elevation curves, respectively, indicating that the dual-scale slope positions are strongly correlated with the actual elevation.

[0065] The spatial distribution differences of soil moisture and nutrients are affected by slope position. Here, soil moisture is taken as an example to check the distribution law of soil moisture at different scales of slope positions, reflecting the advantages of the dual-scale slope position division method. In the quantitative evaluation, soil moisture at different scales of slope positions is counted separately, and the distribution of water content at each scale is counted based on the soil moisture data of the study area (see Figure 6 ). This shows that soil moisture has a significant characteristic of changing with two-scale slope positions, that is, soil moisture is affected by both the overall topography (macro-regional scale slope position) and the micro-topography (local scale slope position of the field). Therefore, in order to characterize the relationship between soil moisture and topography, a slope position division method combining two scales should be used.

[0066] In one embodiment, after determining the distribution pattern of soil moisture or soil nutrients in the target hilly farmland area according to the slope division result, it also includes: predicting the soil moisture values ​​of all other slope positions according to the soil moisture values ​​measured at some slope positions and the distribution pattern of the soil moisture.

[0067] Once the slope position and soil moisture distribution law are determined, they can be widely used. For example, once the soil moisture value of a certain slope position is determined, the soil moisture values ​​of all other slope positions can be predicted based on the above law.

[0068] The multi-scale hilly farmland slope division system provided by the present invention is described below. The multi-scale hilly farmland slope division system described below and the multi-scale hilly farmland slope division method described above can be referenced to each other.

[0069] Optionally, Figure 7 It is a submenu of the multi-scale hilly farmland slope division system provided by the present invention, such as Figure 7 As shown in the figure, the system mainly includes five modules: data loading, data processing, slope division, classification evaluation, and help.

[0070] Among them, the data loading module may include opening a DEM data plug-in, opening a valley line plug-in, opening a ridge line plug-in, opening a soil moisture data plug-in, and opening a soil attribute data plug-in.

[0071] The data processing module is mainly used for DEM filling, slope calculation, scale calculation, statistics and other functions.

[0072] The slope division module is mainly used for simple threshold division, RPI-based division, TPI-based division, DEV-based division and dual-scale slope division.

[0073] The classification evaluation module is mainly used for qualitative evaluation and quantitative evaluation functions.

[0074] The help module mainly includes the About plug-in and the Help Manual plug-in.

[0075] Optionally, Figure 8 This is the main interface and scale calculation schematic diagram of the multi-scale hilly farmland slope division system provided by the present invention, such as Figure 8 As shown in the figure, based on DEM data and soil attribute data, this system calculates the spatial variation characteristics of farmland soil moisture at the plot scale and farm scale, and combines the slopes of the two different scales to form the result of fine slope division of hilly farmland, and then systematically calculates and evaluates the slope division and evaluation.

[0076] The multi-scale hilly farmland slope division system provided by the present invention is based on a terrain position index with scale effect. It uses different scales to divide the slopes and combines the slopes of two different scales to form a fine slope division result of the hilly farmland. It can more accurately reflect the actual terrain characteristics and express the specific soil moisture migration process, and it is easy to operate and has relatively small calculation.

[0077] It should be noted that the multi-scale hilly farmland slope division system provided in the embodiment of the present invention can be implemented based on the multi-scale hilly farmland slope division method described in any of the above embodiments during specific execution, which will not be elaborated in this embodiment.

[0078] Fig. 9 Schematic diagram of the structure of the multi-scale hilly farmland slope division system provided by the present invention. Fig. 9 As shown, the multi-scale hilly farmland slope position division system includes: a scale determination module 901, a slope position division module 902 and a slope position combination module 903. Among them, the scale determination module 901 is used to determine the spatial variation of soil moisture at the regional macro scale and the field local scale according to the soil moisture distribution in the target hilly farmland area, so as to determine the regional macro and field local variation scales; the slope position division module 902 is used to divide the target hilly farmland area according to the regional macro and field local variation scales according to the terrain position index TPI, and obtain the first-level slope position and the second-level slope position; the slope position combination module 903 is used to obtain the fine slope position division result of the target hilly farmland area according to the combination of the first-level slope position and the second-level slope position.

[0079] The system embodiment provided in the embodiment of the present invention is to implement the above-mentioned method embodiments. Please refer to the above-mentioned method embodiments for specific processes and detailed contents, which will not be repeated here.

[0080] The multi-scale hilly farmland slope division system provided by the present invention is based on a terrain position index with scale effect. It uses different scales to divide the slopes and combines two slopes of different sizes to form a fine slope division result of hilly farmland. It can more accurately reflect the actual terrain characteristics and express the specific soil moisture migration process, and it is easy to operate and requires relatively little calculation.

[0081] Fig.10 is a schematic diagram of the structure of the electronic device provided by the present invention, such as Fig.10 As shown, the electronic device may include: a processor 1001, a communication interface 1002, a memory 1003 and a communication bus 1004, wherein the processor 1001, the communication interface 1002 and the memory 1003 communicate with each other through the communication bus 1004. The processor 1001 may call the logic instructions in the memory 1003 to execute a multi-scale hilly farmland slope position division method, the method comprising: determining the spatial variation of soil moisture at the regional macro scale and the field local scale according to the soil moisture distribution of the target hilly farmland area, so as to determine the regional macro and field local variation scales; dividing the target hilly farmland area according to the regional macro and field local variation scales according to the terrain position index TPI, and obtaining the primary slope position and the secondary slope position; obtaining the fine slope position division result of the target hilly farmland area according to the combination of the primary slope position and the secondary slope position.

[0082] In addition, the logic instructions in the above-mentioned memory 1003 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0083] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the multi-scale hilly farmland slope division method provided by the above-mentioned methods, and the method includes: determining the spatial variation of soil moisture at the regional macro scale and the field local scale according to the soil moisture distribution in the target hilly farmland area, so as to determine the regional macro and field local variation scales; dividing the target hilly farmland area according to the terrain position index TPI based on the regional macro and field local variation scales, and obtaining the primary slope position and the secondary slope position; obtaining the fine slope division result of the target hilly farmland area according to the combination of the primary slope position and the secondary slope position.

[0084] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the multi-scale hilly farmland slope division method provided in the above-mentioned embodiments, the method comprising: determining the spatial variation of soil moisture at the regional macro scale and the field local scale according to the soil moisture distribution in the target hilly farmland area, so as to determine the regional macro and field local variation scales; dividing the target hilly farmland area according to the terrain position index TPI based on the regional macro and field local variation scales, respectively, to obtain primary slope positions and secondary slope positions; obtaining a fine slope division result of the target hilly farmland area according to a combination of the primary slope position and the secondary slope position.

[0085] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0086] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-scale hilly farmland slope division method, characterized in that: include: According to the soil moisture distribution in the target hilly farmland area, the spatial variation of soil moisture at the regional macro scale and the field local scale is determined to determine the regional macro and field local variation scale; The target hilly farmland area was divided according to the terrain position index TPI based on the regional macro and field local variation scales, and the first-level slope position and the second-level slope position were obtained; According to the combination of the first-level slope position and the second-level slope position, the fine slope position division result of the target hilly farmland area is obtained; The method of determining the spatial variation of soil moisture at the regional macro scale and the field local scale according to the soil moisture distribution in the target hilly farmland area, so as to determine the regional macro and field local variation scales, includes: According to the soil moisture distribution, the semivariance function of soil moisture values ​​at different scales at the regional macroscale and the field local scale is determined; According to the variation range of the semivariogram function, the variation scales of the macroscopic scale of the region and the local scale of the field are determined respectively; The target hilly farmland area is divided according to the terrain position index TPI based on the regional macro and field local variation scales, and the first-level slope position and the second-level slope position are obtained, including: Based on the regional macro and field local variation scales, the target hilly farmland area is divided into the first-level slope position according to the ratio of TPI to SD and the corresponding threshold, and each field is divided into the second-level slope position; Among them, SD is the standard deviation value of TPI and the neighboring pixel elevation; According to the combination of the primary slope position and the secondary slope position, the fine slope position division results of the target hilly farmland area are obtained, including: According to the first-level slope division, the corresponding first slope index is obtained; According to the secondary slope position division, the corresponding second slope position index is obtained; The first slope index is multiplied by 10 and weighted summed with the second slope index to obtain the refined slope index of the target hilly farmland area.

2. The multi-scale hilly farmland slope division method according to claim 1 is characterized in that: Determining the semi-variance functions of soil moisture values ​​at different scales at the regional macro scale and the field local scale according to the soil moisture distribution includes: Among them, γ(h) is the semivariogram function; Z(X i ) is the soil moisture value corresponding to the pixel, Z(X i+h ) is the soil moisture value corresponding to another pixel with a step size of h; h is the step size, and N(h) is the number of pixel logarithms with a step size of h.

3. The multi-scale hilly farmland slope division method according to any one of claims 1-2, characterized in that: After obtaining the fine slope position division result of the target hilly farmland area, the method further includes: According to the slope position division result, the distribution pattern of soil moisture or soil nutrients in the target hilly farmland area is determined.

4. The multi-scale hilly farmland slope division method according to claim 3 is characterized in that: After determining the distribution law of soil moisture or soil nutrients in the target hilly farmland area according to the slope position division result, the method further includes: The soil moisture values ​​of all other slope positions are predicted based on the soil moisture values ​​measured at some slope positions and the distribution law of the soil moisture.

5. A multi-scale hilly farmland slope classification system, characterized in that: include: The scale determination module is used to determine the spatial variation of soil moisture at the regional macro scale and the field local scale according to the soil moisture distribution in the target hilly farmland area, so as to determine the regional macro and field local variation scale; The slope position division module is used to divide the target hilly farmland area according to the terrain position index TPI based on the regional macro and field local variation scales, and obtain the first-level slope position and the second-level slope position; The slope position combination module is used to obtain the fine slope position division result of the target hilly farmland area according to the combination of the first-level slope position and the second-level slope position; The scale determination module is specifically used for: According to the soil moisture distribution, the semivariance function of soil moisture values ​​at different scales at the regional macroscale and the field local scale is determined; According to the variation range of the semivariogram function, the variation scales of the macroscopic scale of the region and the local scale of the field are determined respectively; The slope position division module is specifically used for: Based on the regional macro and field local variation scales, the target hilly farmland area is divided into the first-level slope position according to the ratio of TPI to SD and the corresponding threshold, and each field is divided into the second-level slope position. Among them, SD is the standard deviation value of TPI and the neighboring pixel elevation; The slope position combination module is specifically used for: According to the first-level slope division, the corresponding first slope index is obtained; According to the secondary slope position division, the corresponding second slope position index is obtained; The first slope index is multiplied by 10 and weighted summed with the second slope index to obtain the refined slope index of the target hilly farmland area.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the multi-scale hilly farmland slope division method as described in any one of claims 1 to 4 are implemented.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the multi-scale hilly farmland slope division method as described in any one of claims 1 to 4 are implemented.

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