A method, system and apparatus for identification and control of spartina

Abstract

The application discloses a method, system and device for identifying and treating Spartina alterniflora, and relates to the field of unmanned aerial vehicles. An orthographic image of the ground is obtained; a Spartina alterniflora patch region is obtained; a spraying amount application map is obtained; an unmanned aerial vehicle sprays medicine on the Spartina alterniflora patch region according to the spraying amount application map and a first spraying mode at a preset height; the unmanned aerial vehicle sprays medicine on the Spartina alterniflora patch region according to the spraying amount application map and a second spraying mode at the preset height; after each spraying application, the Spartina alterniflora patch region is tracked and monitored and the treatment effect is evaluated to obtain an evaluation result every other preset time period; it is determined whether the evaluation result is qualified; if yes, the orthographic image of the ground, the Spartina alterniflora patch region, the spraying amount application map and the evaluation result are stored; if not, the step of obtaining the orthographic image of the ground by means of aerial photography of the unmanned aerial vehicle is executed again. The application realizes accurate identification and prevention and treatment of mixed growth and sporadic patch distribution of Spartina alterniflora.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned aerial vehicles, in particular to a method, system and device for identifying and treating Spartina alterniflora. BACKGROUND

[0002] Since Spartina alterniflora was introduced into China in 1979, it has rapidly expanded in coastal areas and has become the most harmful invasive plant on coastal beaches. Spartina alterniflora is a perennial herb with tall and dense plants, and has characteristics of flood tolerance, salt tolerance and developed root system. Its propagation methods include sexual reproduction by seeds and asexual reproduction by rhizomes or nutrient fragments. The existing treatment technology for Spartina alterniflora is based on the principle of limiting the growth, sexual reproduction and asexual reproduction of Spartina alterniflora simultaneously, so as to control the spread or completely eliminate it. According to preliminary investigation, the area of Spartina alterniflora in China is about 68,000 mu, and the prevention and control situation is extremely severe. On February 16, 2023, the national Spartina alterniflora prevention and control work site meeting was held in Ningde, Fujian Province, and the “Special Action Plan for Spartina alterniflora Prevention and Control (2022-2025)” was formulated. In order to improve the quality and stability of the coastal wetland ecosystem in China, effectively curb the spread of Spartina alterniflora, and ensure the ecological safety of the coastal wetland, China has launched a special action for Spartina alterniflora prevention and control. Through four years of concentrated prevention and control, it is expected that by 2025, the Spartina alterniflora in China will be effectively controlled, and the elimination rate in each province will be more than 90%.

[0003] From the current practical experience, the comprehensive treatment method is more effective. Common comprehensive treatment methods for Spartina alterniflora include “mowing + flooding”, “mowing + plowing”, and herbicide treatment. Combined with the existing practical experience in the local area, the “mowing + flooding” method, which cuts off the Spartina alterniflora, uses water to flood the remaining roots, and plants native plants such as Scirpus mariqueter and Phragmites australis to adjust the salinity of the water system, achieving the purpose of ecological restoration. This method has been proven to be the best, most complete, and has a low recurrence rate. Considering the safety factors of the surrounding beach affected by the tides, the construction of cofferdams is difficult, the construction period is long, the construction impact is large, and the investment is large. The “mowing + plowing” method has more practical experience in Shandong, Fujian and other places. The methods used in different regions vary due to differences in soil, temperature, etc. At the same time, this method has very high requirements for plowing construction quality, and the construction difficulty, construction period and investment are relatively high, and the recurrence rate is difficult to control.

[0004] However, the current chemical treatment of Spartina alterniflora is a rough and extensive method of uniform spraying over a large area. For sporadic patches of recurrent and secondary invasion, such as seed coverage, there are problems such as low treatment efficiency, waste of chemicals, and significant impact on native plants.

[0005] The current Spartina alterniflora treatment technology is mostly based on farmland weed control technology. However, there is a lack of an efficient and ecological precise treatment technology for Spartina alterniflora in the coastal beach environment, especially for sporadic patch distribution.

[0006] (1) On the identification of Spartina alterniflora, the current technology has some basic research on remote sensing image interpretation, but there are great differences in the growth and coverage of Spartina alterniflora in each real area. If the old parameters are followed, it may bring a large error, leading to missed spraying, even misidentification, and misidentifying important native plants such as reeds as Spartina alterniflora for treatment.

[0007] (2) Variable spraying technology, at present, for farmland, the method of generating NDVI index according to multispectral image can automatically generate variable spraying prescription map, but for sporadic patch distribution of Spartina alterniflora or mixed growth with reed, there is no mature scheme for automatic variable spraying, especially in the implementation process of flight line planning and spraying parameters, which needs to rely on this technology to manually make spraying scheme. SUMMARY

[0008] The purpose of the embodiment of the application is to provide a method, system and device for identifying and treating Spartina alterniflora, which uses two unmanned aerial vehicles of multispectral unmanned aerial vehicle and agricultural plant protection unmanned aerial vehicle, proposes a precise treatment method for sporadic patch distribution of Spartina alterniflora, and can realize accurate identification and control of mixed growth and sporadic patch distribution of Spartina alterniflora. Compared with the prior art, the beneficial effects of treatment effect, treatment cost and ecological environmental protection are greatly improved. The influence of drug spraying on the environment is local and controllable, and will not cause large-scale pollution. The negative impact on fish, large benthic animals and birds is reduced.

[0009] To achieve the above purpose, the embodiment of the application provides the following scheme:

[0010] A method for identifying and treating Spartina alterniflora, comprising:

[0011] obtaining a ground orthographic image by unmanned aerial vehicle aerial photography; controlling the ground resolution in the centimeter range by real-time dynamic difference during aerial photography; obtaining a Spartina alterniflora patch area larger than a preset area threshold by computer automatic interpretation of the ground orthographic image by maximum likelihood method;

[0012] obtaining a spraying amount application map according to the Spartina alterniflora patch area and the normalized vegetation index;

[0013] when the Spartina alterniflora patch area is larger than a first preset area threshold, spraying drug on the Spartina alterniflora patch area according to the spraying amount application map and a first spraying mode at a preset height by the unmanned aerial vehicle; the first spraying mode is sea three-prong rush-Spartina alterniflora mixed growth area spraying;

[0014] when the Spartina alterniflora patch area is less than or equal to a first preset area threshold, the unmanned aerial vehicle sprays the Spartina alterniflora patch area according to the spraying amount application map and a second spraying mode at a preset height; the second spraying mode is a reed-Spartina alterniflora mixed area spraying mode.

[0015] After each spraying application, the Spartina alterniflora patch area is tracked and monitored and the control effect is evaluated every other preset time period to obtain an evaluation result.

[0016] It is judged whether the evaluation result is qualified; if yes, the ground orthographic image, the Spartina alterniflora patch area, the spraying amount application map and the evaluation result are stored; if no, the step of obtaining the ground orthographic image by aerial photography of the unmanned aerial vehicle is performed again.

[0017] Optionally, the spraying amount application map is obtained according to the Spartina alterniflora patch area and a normalized difference vegetation index (NDVI), and specifically includes:

[0018] The calculation formula of the normalized difference vegetation index is:

[0019] NDVI=(NIR-Red) / (NIR+Red);

[0020] wherein, NDVI is the normalized difference vegetation index; NIR is the near-infrared band reflectivity; Red is the red band reflectivity; the range of the normalized difference vegetation index is always -1 to +1.

[0021] The normalized difference vegetation index is generated into a variable application map by a three-level hierarchical method; specifically including:

[0022] wherein, the application amount of the Spartina alterniflora patch area with the normalized difference vegetation index below 0.01 is 0; the application amount of the Spartina alterniflora patch area with the normalized difference vegetation index between 0.01 and 0.11 is a medium application amount; the application amount of the Spartina alterniflora patch area with the normalized difference vegetation index above 0.11 is a large application amount.

[0023] Optionally, the spraying amount application map is obtained according to the Spartina alterniflora patch area and the normalized difference vegetation index, and further includes:

[0024] The Spartina alterniflora patch area is converted into a raster image; the coordinate system of the raster image is set as WGS84, and the pixel size is ;

[0025] Through raster operation, the grid value of the Spartina alterniflora patch area in the ground orthographic image is set as the planned application amount per mu, and the grid value of the Spartina alterniflora patch area is set as 0 to obtain the spraying amount application map.

[0026] Optionally, the first spraying mode specifically includes:

[0027] The bow-shaped spraying route is set for each Spartina alterniflora patch, the longitudinal distance of the bow-shaped spraying route is determined by the distribution range of Spartina alterniflora, and the transverse distance of the bow-shaped spraying route is the working row distance; in the case that the wind force is greater than a preset wind force level, the area of each Spartina alterniflora patch can be expanded by 1-2 working row distances.

[0028] Optionally, the second spraying mode specifically comprises:

[0029] The adjacent Spartina alterniflora patches are integrated into a spraying area with a preset area size, and the bow-shaped spraying route is set for each spraying area; the longitudinal distance of the bow-shaped spraying route is determined by the outermost boundary of the spraying area, and the transverse distance of the bow-shaped spraying route is the working row distance; in the case that the wind force is greater than a preset wind force level, each spraying area can be expanded by 1-2 working row distances.

[0030] Optionally, the first spraying mode further comprises:

[0031] The spraying is performed 3 times in June-August every year;

[0032] The working row distance is less than 6 m, the preset height is less than 2 m, the bow-shaped spraying route overlap is 0.5 m, and the flight speed of the unmanned aerial vehicle is less than 5.5 m / s.

[0033] Optionally, the second spraying mode further comprises:

[0034] The reed-Spartina alterniflora mixed area is sprayed in April every year;

[0035] The working row distance is less than 6 m, the preset height is less than 3.2 m, the bow-shaped spraying route overlap is 0.5 m, and the flight speed of the unmanned aerial vehicle is less than 5 m / s;

[0036] The reed-Spartina alterniflora mixed area is mowed in June-September every year.

[0037] To achieve the above object, the embodiment of the present application further provides the following scheme:

[0038] A Spartina alterniflora identification and removal system, comprising:

[0039] A Spartina alterniflora patch area acquisition module, which acquires a ground orthographic image in a manner of unmanned aerial vehicle aerial photography; the ground resolution is controlled in a centimeter range by using real-time dynamic difference in the aerial photography process; the ground orthographic image is automatically interpreted by a computer by using a maximum likelihood method to obtain a Spartina alterniflora patch area greater than a preset area threshold value;

[0040] The spraying amount application map calculation module is connected with the Spartina alterniflora patch area acquisition module and is configured to obtain a spraying amount application map according to the Spartina alterniflora patch area and the normalized difference vegetation index.

[0041] The drug spraying control module is connected with the spraying amount application map calculation module and is configured to:

[0042] When the Spartina alterniflora patch area is greater than the first preset area threshold, the unmanned aerial vehicle sprays the drug on the Spartina alterniflora patch area according to the spraying amount application map and a first spraying mode at a preset height; the first spraying mode is a Spartina pectinata-Spartina alterniflora mixed area spraying.

[0043] When the Spartina alterniflora patch area is less than or equal to the first preset area threshold, the unmanned aerial vehicle sprays the drug on the Spartina alterniflora patch area according to the spraying amount application map and a second spraying mode at a preset height; the second spraying mode is a Phragmites australis-Spartina alterniflora mixed area spraying.

[0044] The evaluation result output module is connected with the drug spraying control module and is configured to:

[0045] After each spraying application, the Spartina alterniflora patch area is tracked and monitored and the control effect is evaluated every other preset time period to obtain an evaluation result.

[0046] It is judged whether the evaluation result is qualified; if yes, the ground orthographic image, the Spartina alterniflora patch area, the spraying amount application map and the evaluation result are stored; if no, the step of acquiring the ground orthographic image by means of aerial photography of the unmanned aerial vehicle is executed again.

[0047] An electronic device includes a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor implements the Spartina alterniflora identification and control method when executing the computer program.

[0048] A non-transitory computer readable storage medium has a computer program stored thereon, and the computer program is executed to implement the Spartina alterniflora identification and control method.

[0049] In the embodiment of the present application, based on the multi-spectral unmanned aerial vehicle aerial image with real-time differential positioning function (RTK), the rapid and accurate interpretation and identification are carried out on the Spartina alterniflora patch distribution or the boundary of mixed distribution with local species; under the premise of ensuring the treatment effect, the chemical application operation plan for the scattered Spartina alterniflora patch is made by using the unmanned aerial vehicle image interpretation result, the route optimization and variable spraying technology are combined, and the priority and application specification of the application area are determined by comprehensively considering the wind speed and tide level, so that the amount of medicine is saved to the maximum extent, the influence on the ecological environment is reduced, and the treatment efficiency of Spartina alterniflora is improved. BRIEF DESCRIPTION OF DRAWINGS

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor under the premise of the drawings.

[0051] Figure 1 The flowchart of the identification and treatment method of Spartina alterniflora provided by the embodiment of the present application;

[0052] Figure 2 The detailed structure diagram of the identification and treatment system of Spartina alterniflora provided by the embodiment of the present application;

[0053] Figure 3 The Spartina alterniflora pattern under various illumination and growth states provided by the embodiment of the present application;

[0054] Figure 4 The accurate delimitation of the treatment area according to the Spartina alterniflora provided by the embodiment of the present application;

[0055] Figure 5 The unmanned aerial vehicle NDVI index and spraying amount application schematic diagram of the typical area provided by the embodiment of the present application;

[0056] Figure 6 The manual preparation of the spraying amount application diagram provided by the embodiment of the present application;

[0057] Figure 7 The DSM elevation distribution diagram of the typical area provided by the embodiment of the present application;

[0058] Figure 8 The dynamic implementation scheme schematic diagram according to the area and partition provided by the embodiment of the present application;

[0059] Figure 9 The treatment area and scheme schematic diagram of Chongming Dongtan provided by the embodiment of the present application;

[0060] Figure 10 The before-and-after comparison diagram of the treatment effect is provided for the embodiments of the present invention;

[0061] Figure 11 This is a map showing the zoning of the Nanhui coastal area for governance, provided as an embodiment of the present invention.

[0062] Figure 12 A comparison diagram of the effects of Nanhui beach management provided in an embodiment of the present invention;

[0063] Figure 13 A governance area division map provided for embodiments of the present invention;

[0064] Figure 14 This is a comparison chart of the governance effects in Jinshan provided in an embodiment of the present invention;

[0065] Figure 15 A flowchart provided for an embodiment of the present invention.

[0066] Symbol explanation:

[0067] Spartina alterniflora patch area acquisition module - 100, spraying rate calculation module - 200, pesticide spraying control module - 300, evaluation result output module - 400. Detailed Implementation

[0068] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0069] The purpose of this invention is to provide a method, system, and device for identifying and controlling Spartina alterniflora, in order to solve the prominent problems of low control efficiency, excessive waste of pesticides, and significant impact on native plants.

[0070] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0071] Figure 1 and Figure 15 An exemplary process for identifying and controlling Spartina alterniflora as described above is shown. The steps are described in detail below.

[0072] Step S1: Obtain ground orthophotos using drone aerial photography; during the aerial photography process, use real-time dynamic difference to control the ground resolution within the centimeter range; use the maximum likelihood method to automatically interpret the ground orthophotos using a computer to obtain Spartina alterniflora patch areas larger than a preset area threshold.

[0073] In one example, the area of the Spartina alterniflora patch requiring treatment is accurately demarcated. Before the treatment of scattered Spartina alterniflora patches, a multispectral unmanned aerial vehicle is generally used for aerial photography to generate a ground orthographic image. During the aerial photography, the real-time dynamic difference (RTK) function needs to be turned on, and the ground resolution is controlled within the centimeter range. According to the high-resolution orthographic image, computer automatic interpretation is performed according to different map patches. The machine learning algorithm of the maximum likelihood method is used for interpretation, various growth state map patches need to be input, please refer to Figure 3 , and the output result is the distribution area. In combination with ground inspection, the area of the Spartina alterniflora patch larger than 1.0 m2 is finally accurately identified, please refer to Figure 4 .

[0074] Step S2: obtaining a spraying amount application map according to the Spartina alterniflora patch area and the normalized difference vegetation index; specifically comprising:

[0075] Step S21: the calculation formula of the normalized difference vegetation index is:

[0076] NDVI=(NIR-Red) / (NIR+Red);

[0077] wherein, NDVI is the normalized difference vegetation index; NIR is the near-infrared band reflectivity; Red is the red band reflectivity; the range of the normalized difference vegetation index is always -1 to +1;

[0078] Step S22: generating a variable application map by using a 3-level stratification method for the normalized difference vegetation index; specifically comprising:

[0079] wherein, the application amount of the Spartina alterniflora patch area with the normalized difference vegetation index below 0.01 is 0; the application amount of the Spartina alterniflora patch area with the normalized difference vegetation index between 0.01 and 0.11 is a medium application amount; and the application amount of the Spartina alterniflora patch area with the normalized difference vegetation index above 0.11 is a large application amount.

[0080] Step S23: converting the Spartina alterniflora patch area into a raster image; the coordinate system of the raster image is set to WGS84, and the pixel size is ;

[0081] Step S24: through raster operation, setting the grid value of the ground orthographic image which is not the Spartina alterniflora patch area to 0, and setting the grid value of the Spartina alterniflora patch area to the planned application amount per mu, to obtain the spraying amount application map.

[0082] In one example, for the uncontrolled Spartina alterniflora, its distribution is sparse and scattered, and the automatic generation of spraying amount application map method is generally adopted. Based on the aerial image of multi-spectral unmanned aerial vehicle, the normalized vegetation index (NDVI) is calculated to reflect the coverage, classification, crop growth and other aspects of the vegetation, which effectively improves the recognition and classification accuracy of the image, please refer to Figure 5 .

[0083] Therefore, the nearest neighbor interpolation method is selected to combine the spraying width of the plant protection unmanned aerial vehicle for resampling, and the NDVI index in the Spartina alterniflora patch image is converted into the spraying amount in turn, and the result can be used to quantitatively guide the variable and precise spraying of the plant protection unmanned aerial vehicle. The specific conversion method is that for the NDVI index, a 3-level stratification method is used to generate a variable spraying map.

[0084] For the Spartina alterniflora that has been controlled twice or scattered distribution, its distribution is relatively concentrated, and the manual preparation of spraying amount application map method is generally adopted.

[0085] Based on the Spartina alterniflora distribution range interpreted in step S1, the entire management area and the Spartina alterniflora distribution range are converted into a grid image, wherein the coordinate system is set as WGS84, and the cell size is 1e-06. Through grid operation, the grid value of the area without Spartina alterniflora is set to 0, and the grid value of the Spartina alterniflora distribution area is set to the planned spraying amount per mu, and finally a complete spraying map covering the management area is generated. Please refer to Figure 6 , import the plant protection machine remote controller, and the next route planning step can be performed.

[0086] Step S3: when the Spartina alterniflora patch area is greater than the first preset area threshold, the unmanned aerial vehicle sprays the Spartina alterniflora patch area according to the spraying amount application map and the first spraying mode at a preset height; the first spraying mode is a Spartina pectinata-Spartina alterniflora mixed area spraying;

[0087] The first spraying mode specifically includes:

[0088] An arch-shaped spraying route is set for each Spartina alterniflora patch; the longitudinal distance of the arch-shaped spraying route is determined by the Spartina alterniflora distribution range, and the transverse distance of the arch-shaped spraying route is the working row spacing; in the case that the wind force is greater than the preset wind force level, the area of each Spartina alterniflora patch can be expanded by 1-2 working row spacings.

[0089] Spraying is performed 3 times in June-August every year;

[0090] The working row spacing is less than 6m, the preset height is less than 2m, the overlap degree of the arch-shaped spraying route is 0.5m, and the flight speed of the unmanned aerial vehicle is less than 5.5m / s.

[0091] In one example, the height of the unmanned aerial vehicle for pesticide application is determined. The image taken by the unmanned aerial vehicle is first subjected to image denoising, enhancement and distortion correction processing, and then a scale invariant feature transformation algorithm is used to match the image. The matched image is represented as a feature vector set. Through regional network adjustment processing, high-precision exterior orientation elements are obtained. Based on distributed matching, regional DSMs in each direction are generated. Finally, the DSM images are fused to construct a DSM image, please refer to Figure 7 . During pesticide application, the plant protection machine realizes the height-keeping flight function based on the DSM, so as to maintain the height of the plant protection machine relative to the Spartina alterniflora canopy constant, thereby ensuring that the working row distance is constant and no missed spraying occurs during pesticide application.

[0092] Step S4: When the Spartina alterniflora patch area is less than or equal to the first preset area threshold, the unmanned aerial vehicle sprays pesticide on the Spartina alterniflora patch area according to the spraying amount and the second spraying mode at a preset height; the second spraying mode is reed-Spartina alterniflora mixed area spraying.

[0093] The second spraying mode specifically includes:

[0094] Adjacent Spartina alterniflora patches are integrated into a pesticide application area with a preset area size, and an arch-shaped pesticide application route is set for each pesticide application area. The longitudinal distance of the arch-shaped pesticide application route is determined by the outermost boundary of the pesticide application area, and the transverse distance of the arch-shaped pesticide application route is the working row distance. In the case where the wind force is greater than the preset wind force level, each pesticide application area can be expanded by 1-2 working row distances.

[0095] The reed-Spartina alterniflora mixed area is sprayed every April.

[0096] The working row distance is less than 6 m, the preset height is less than 3.2 m, the overlap degree of the arch-shaped pesticide application route is 0.5 m, and the flight speed of the unmanned aerial vehicle is less than 5 m / s.

[0097] The reed-Spartina alterniflora mixed area is mowed every June-September.

[0098] In one example, according to the characteristics of the elevation change of the Spartina alterniflora growing area, based on the accurate Spartina alterniflora plane distribution obtained in step S1, the Spartina alterniflora treatment is planned in different zones, and the patch distribution, range and size of Spartina alterniflora treatment in different zones are determined. According to the field survey and the endurance time of the unmanned aerial vehicle, the terrain measurement accuracy requirements, the flight range of each flight is set in the remote controller according to the results of the previous interpretation. The range should be set considering the coverage. It is recommended that under the condition of wind force less than 3, the height of the plant protection machine is 2.5 m, the speed is less than 5 m / s, and the operation row spacing is 5.5 m, and the route planning is carried out. According to the distribution type of Spartina alterniflora, on the basis of the previous accurate interpretation, the growth characteristics of plants are considered, and the following two flight schemes are adopted:

[0099] (1) Based on the distribution characteristics and accurate treatment requirements of the sporadic patches of Spartina alterniflora, the first spraying mode (the first method) is adopted for the large patch distribution of Spartina alterniflora with an area greater than 4 m2. Please refer to the left half of Figure 8 , an arch-shaped application route is set for each patch, and the longitudinal distance of the arch-shaped route is determined by the distribution range of Spartina alterniflora. The lateral distance between routes, i.e. the operation row spacing. In the case of wind force greater than 1, the area of the patch can be expanded by 1-2 operation row spacings, so as to avoid drift and ensure that the application range covers each large patch.

[0100] (2) For small patch distribution with an area less than 4 m2, the second spraying mode (the second method) shown in the right half of Figure 8 is adopted. Specifically, adjacent patches are integrated into a 600 m2 application area, and an arch-shaped application route is set for each application area. The longitudinal distance of the arch-shaped route is determined by the outermost boundary of the sporadic distribution of Spartina alterniflora, and the lateral distance between routes, i.e. the operation row spacing. In the case of wind force greater than 1, the area of the patch at the boundary can be expanded by 1-2 operation row spacings. Fly over the area without Spartina alterniflora, but only apply precise application when flying over the Spartina alterniflora patch.

[0101] In actual operation, generally the above two flight schemes are used in combination. Considering the treatment efficiency, large sporadic patches and small sporadic patches can be combined, and the signed spraying amount application map is used for pesticide spraying. The specific operation area is generally the operation area of one flight of the plant protection machine or less than 8000 m2.

[0102] Please refer to Figure 9, the experience of Shanghai Chongming Dongtan Bird National Nature Reserve and the Technical Specification for Spartina alterniflora Ecological Control issued by Shanghai Forestry Standardization Technical Committee, and the use of Dow AgroSciences' Gaucho (main ingredient: 10.8% fluazifop-butyl), with a dosage of 140-180 mL per mu. For areas with varying elevations, accurate topographic measurement is carried out in the early stage to achieve variable-height spraying, avoiding excessive spraying that wastes pesticide or insufficient spraying that misses some areas. Field spraying is carried out during low tide, sunny, and windless weather to spray wet stems and leaves, and to avoid pesticide dripping onto the soil surface. The sprayed area should not be affected by rain or tide within 6 hours after spraying.

[0103] Spartina alterniflora is distributed in scattered patches. Based on the area of the patches and the mixing of Spartina alterniflora with native plants, the following two spraying techniques are used:

[0104] (1) Spraying in areas where Scirpus mariqueter and Spartina alterniflora grow together

[0105] Since the target species of fluazifop-butyl is grasses, it has no effect on Scirpus mariqueter. Therefore, in areas where Scirpus mariqueter and Spartina alterniflora grow together, the distribution patches of Spartina alterniflora are accurately identified and interpreted in the early stage, and the flight path of the plant protection aircraft is planned reasonably to ensure that no area is missed or oversprayed. This ensures that the control target of Spartina alterniflora is achieved while having no significant impact on the Scirpus mariqueter community.

[0106] Spraying is carried out 3 times in an orderly manner from June to August each year. The spraying effect is checked after each spraying, and areas that are not sprayed or do not meet the standards are immediately resprayed. The checking is repeated at least 3 times to ensure that each spraying area is not missed and the quality and effect meet the standards.

[0107] The flight path is in the shape of a bow, the working width is less than 6 m, the working height is dynamically adjusted according to the height of Spartina alterniflora and is generally less than 2.0 m, the flight path overlap is 0.5 m, and the flight speed of the plant protection aircraft is less than 5.5 m / s.

[0108] (2) Spraying in areas where Phragmites australis and Spartina alterniflora grow together

[0109] Spartina alterniflora control is carried out in areas where Spartina alterniflora and Phragmites australis grow together in April each year, when Spartina alterniflora has germinated but Phragmites australis has not. Since Phragmites australis has not germinated at this time, the pesticide cannot be absorbed by the leaves. Therefore, this time window can be used to spray the already germinated Spartina alterniflora, which will not have an eradication effect on Phragmites australis, effectively controlling Spartina alterniflora while minimizing the impact on Phragmites australis. The flight path is in the shape of a bow, the working width is less than 6 m, the working height is dynamically adjusted according to the height of Spartina alterniflora and is generally less than 3.2 m, the flight path overlap is 0.5 m, and the flight speed of the plant protection aircraft is less than 5 m / s.

[0110] From June to September, in areas where Spartina alterniflora and Phragmites australis grow together, the reed stems and leaves (the main absorption tissue for chemical agents) are removed by mowing, and then the Spartina alterniflora patches are sprayed with the aforementioned chemical spraying method. Experiments have shown that chemical spraying does not affect the emergence of reed seedlings after mowing and reduces the cost of subsequent reed restoration.

[0111] Step S5: After each spraying application, the *Spartina alterniflora* patches are monitored and the control effect is evaluated at preset time intervals. For the evaluation results, please refer to [link to relevant documentation]. Figure 10 ;

[0112] Step S6: Determine whether the evaluation result is qualified; if yes, store the ground orthophoto image, the area of ​​Spartina alterniflora patch, the spraying amount map and the evaluation result; if no, execute the step of "obtaining ground orthophoto image by means of drone aerial photography" again.

[0113] In one example, because the herbicide is absorbed by the stems, leaves, or roots of *Spartina alterniflora* and transported throughout the plant, it inhibits the meristematic tissues of the stems and roots, leading to death. Untreated *Spartina alterniflora* plants generally remain green and require supplementary application to ensure the first application effectively covers the affected area. Since the first application only affects *Spartina alterniflora* plants that have reached a certain height, some shorter or newly sprouted plants are covered by the taller plants and the first application has no effect on them. These plants will only grow after some of the later-emerging seedlings wilt following the application of the herbicide to the taller plants. The second application of pesticide can be carried out as soon as the grass is exposed. The first two applications have caused severe damage to both the above-ground and underground parts of the rapidly growing Spartina alterniflora. The above-ground parts have died in large areas, and the underground parts have also tended to rot (but have not been completely inactive and still have a certain ability to regenerate). In order to completely kill the remaining possible surviving tissues, further consolidate the effect of the pesticide application, and prevent the rebound, a third application of pesticide should be carried out. The effect should be closely monitored and any omissions should be addressed. Attention should be paid to sporadic patches of Spartina alterniflora to fully achieve the goal of controlling Spartina alterniflora in the implementation area.

[0114] The control effect of Spartina alterniflora in the implemented area will be monitored every 10 days after each application. The effect evaluation period is 5 days. Areas that have been missed or where the effect is not up to standard (such as Spartina alterniflora still growing well) will be sprayed again in a timely manner. All relevant data and images of the application and monitoring process and the effect must be recorded and archived.

[0115] The specific implementation method is as follows:

[0116] Example 1: Treatment of scattered patches in Chongming East Beach

[0117] Within the 500-mu experimental area of ​​Dongwangsha, Chongming East Beach (121°54′22.31″, 31°35′33.52″), please refer to... Figure 11, for the sporadic distribution of Spartina alterniflora, using Figure 8 The second type of scheme saves 60% compared to the uniform use of drugs in the whole area, and has little effect on important native plants such as reed, Suaeda and sea three-lens grass, etc. On the premise of ensuring the treatment effect, the ecological environment is greatly protected.

[0118] Example 2: Spartina alterniflora-reed mixed treatment in Nanhui beach.

[0119] In the 150 mu test area of Nanhui beach (121°58'27.41", 30°55'12.56"), for the obvious boundary distribution of Spartina alterniflora and reed, using Figure 8 The first type of scheme, on the basis of accurate interpretation in the early stage, accurately demarcates the boundary of Spartina alterniflora and reed (resolution 5cm); in terms of drug application time, it chooses to apply drugs in April when Spartina alterniflora has a certain height and reed has not yet grown, which maximizes the preservation of important native plants-reed on the premise of ensuring the treatment effect, please see Figure 12 .

[0120] Example 3: pure Spartina alterniflora treatment in Jinshan beach

[0121] In the 560 mu test area of Jinshan beach (121°18'7.64", 30°41'56.49"), for the obvious boundary distribution of Spartina alterniflora and reed, combined with Figure 13 The first type and the second type of combined scheme, on the premise of ensuring the treatment effect, please see Figure 14 , the treatment efficiency is improved by 20% compared with the traditional method.

[0122] In summary, in the embodiments of the present application, based on the multi-spectral unmanned aerial vehicle aerial image with real-time differential positioning function (RTK), for the distribution of Spartina alterniflora patches or the boundary of mixed distribution with local species, etc. Quickly and accurately interpret and identify; on the premise of ensuring the treatment effect, use the unmanned aerial vehicle image interpretation result to make a chemical spraying operation plan for the sporadic patches of Spartina alterniflora, combine with route optimization, variable spraying technology, and comprehensively consider the wind speed, tide level to determine the priority and spraying specification of the spraying area, maximize the saving of drug amount, while reducing the impact on the ecological environment, and improve the treatment efficiency of Spartina alterniflora.

[0123] To achieve the above purpose, the embodiments of the present application also provide the following schemes:

[0124] A recognition and treatment system for Spartina alterniflora, please see Figure 2 , comprising:

[0125] The Spartina alterniflora patch area acquisition module 100 adopts the aerial photography mode of the unmanned aerial vehicle to obtain the ground orthographic image; the ground resolution is controlled in the centimeter level range by using the real-time dynamic difference in the aerial photography process; the ground orthographic image is calculated by using the maximum likelihood method to obtain the Spartina alterniflora patch area greater than the preset area threshold;

[0126] The spraying amount application map calculation module 200 is connected with the Spartina alterniflora patch area acquisition module 100, and the spraying amount application map calculation module 200 is used for obtaining the spraying amount application map according to the Spartina alterniflora patch area and the normalized vegetation index;

[0127] The drug spraying control module 300 is connected with the spraying amount application map calculation module 200, and the drug spraying control module 300 is used for:

[0128] When the Spartina alterniflora patch area is greater than the first preset area threshold, the unmanned aerial vehicle sprays the drug on the Spartina alterniflora patch area according to the spraying amount application map and the first spraying mode at a preset height; the first spraying mode is the Spartina pectinata-Spartina alterniflora mixed area spraying;

[0129] When the Spartina alterniflora patch area is less than or equal to the first preset area threshold, the unmanned aerial vehicle sprays the drug on the Spartina alterniflora patch area according to the spraying amount application map and the second spraying mode at a preset height; the second spraying mode is the Phragmites australis-Spartina alterniflora mixed area spraying;

[0130] The evaluation result output module 400 is connected with the drug spraying control module 300, and the evaluation result output module 400 is used for:

[0131] After each spraying application, the Spartina alterniflora patch area is tracked, monitored and evaluated for the treatment effect every other preset time period to obtain the evaluation result;

[0132] It is judged whether the evaluation result is qualified or not; if yes, the ground orthographic image, the Spartina alterniflora patch area, the spraying amount application map and the evaluation result are stored; if not, the step of obtaining the ground orthographic image by using the aerial photography mode of the unmanned aerial vehicle is executed again.

[0133] Further, the present application also provides an electronic device, which can include a processor, a communication interface, a memory and a communication bus. Wherein, the processor, the communication interface, the memory complete the communication among each other through the communication bus. The processor can call the computer program in the memory to execute the computer program to realize the Spartina alterniflora identification and treatment method.

[0134] In addition, the computer program in the memory described above is realized in the form of a software function unit and sold or used as an independent product, and can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes several instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory, a random access memory, a magnetic disk or an optical disk, and various media that can store program codes.

[0135] Further, the present application also provides a non-transitory computer readable storage medium, having stored thereon a computer program, the computer program being executed to implement the Spartina alterniflora identification and control method.

[0136] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts of each embodiment can be referred to each other. For the system disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method part.

[0137] The principles and implementation manners of the embodiments of the present application are described by using specific examples in this paper. The above embodiment description is only used to help understand the method and core idea of the embodiments of the present application; at the same time, for those skilled in the art, according to the idea of the embodiments of the present application, the specific implementation manner and application range will be changed. In conclusion, the content of the specification should not be understood as a limitation of the embodiments of the present application.

Claims

1. A method for identifying and controlling Spartina alterniflora, characterized in that, include: Orthophotos of the ground were obtained using drone aerial photography. During aerial photography, real-time dynamic differential is used to control the ground resolution within the centimeter range; The maximum likelihood method was used to automatically interpret the ground orthophoto image by computer to obtain Spartina alterniflora patch areas larger than a preset area threshold. Based on the described Spartina alterniflora patch areas and normalized difference vegetation index (NDPI), a spraying rate application map was obtained, specifically including: The formula for calculating the normalized vegetation index is as follows: NDVI = (NIR - Red) / (NIR + Red); Wherein, NDVI is the Normalized Difference Vegetation Index; NIR is the Near Infrared Reflectance; Red is the Red Reflectance; the Normalized Difference Vegetation Index always ranges from -1 to +1. The normalized vegetation index was used to generate a variable application map using a three-level stratification method; specifically including: Specifically, the application rate for Spartina alterniflora patches with a normalized vegetation index (NWRI) below 0.01 is 0; the application rate for Spartina alterniflora patches with an NWRI between 0.01 and 0.11 is a medium application rate; and the application rate for Spartina alterniflora patches with an NWRI above 0.11 is a high application rate. When the *Spartina alterniflora* patch area is larger than a first preset area threshold, the drone sprays the *Spartina alterniflora* patch area at a preset altitude according to the spraying volume application map and a first spraying mode; the first spraying mode is spraying the mixed area of ​​*Scirpus triquetrum* and *Spartina alterniflora*; the first spraying mode specifically includes: A bow-shaped application route is set for each Spartina alterniflora patch; the longitudinal distance of the bow-shaped application route is determined by the distribution range of Spartina alterniflora, and the lateral distance of the bow-shaped application route is the row spacing; when the wind force is greater than the preset wind force level, the area of ​​each Spartina alterniflora patch can be expanded by 1 to 2 row spacings. The first spraying mode also includes: Three applications of pesticides are carried out each year from June to August. The row spacing is less than 6m, the preset height is less than 2m, the overlap of the bow-shaped application route is 0.5m, and the drone flight speed is less than 5.5m / s; When the area of ​​*Spartina alterniflora* patches is less than or equal to a first preset area threshold, the drone sprays pesticide on the *Spartina alterniflora* patches at a preset altitude according to the spraying volume application map and the second spraying mode; the second spraying mode is spraying on mixed reed-*Spartina alterniflora* areas; the second spraying mode specifically includes: Adjacent Spartina alterniflora patches are integrated into a spraying area of ​​a preset size, and a bow-shaped spraying route is set for each spraying area; the longitudinal distance of the bow-shaped spraying route is determined by the outermost boundary of the spraying area, and the lateral distance of the bow-shaped spraying route is the row spacing; when the wind force is greater than the preset wind force level, each spraying area can be expanded by 1 to 2 row spacings. The second spraying mode also includes: Spray the aforementioned areas where reeds and Spartina alterniflora grow together every April; The row spacing is less than 6m, the preset height is less than 3.2m, the overlap of the bow-shaped application route is 0.5m, and the drone flight speed is less than 5m / s; The areas where reeds and Spartina alterniflora grow together are mowed from June to September each year. After each spraying application, the Spartina alterniflora patch area is tracked and monitored at preset time intervals to evaluate the control effect and obtain the evaluation results. Determine whether the evaluation result is qualified; if yes, store the ground orthophoto image, the area of ​​Spartina alterniflora patch, the spraying amount map and the evaluation result; if no, execute the step of "obtaining ground orthophoto image by means of UAV aerial photography" again.

2. The method for identifying and controlling Spartina alterniflora according to claim 1, characterized in that, Based on the described Spartina alterniflora patch areas and normalized difference vegetation index (NDPI), a spraying rate map was obtained, which also includes: The Spartina alterniflora patch region was converted into a raster image; the coordinate system of the raster image was set to WGS84, and the cell size was [missing information]. ; By performing grid operations, the grid values ​​of areas that are not Spartina alterniflora patches in the ground orthophoto map are set to 0, and the grid values ​​of the Spartina alterniflora patch areas are set to the planned application rate per acre, thus obtaining the spraying rate application map.

3. A system for identifying and controlling Spartina alterniflora, characterized in that, The Spartina alterniflora identification and control system implements the Spartina alterniflora identification and control method as described in claim 1 or 2, comprising: The Spartina alterniflora patch region acquisition module uses drone aerial photography to acquire ground orthophotos; during the aerial photography process, real-time dynamic difference is used to control the ground resolution within the centimeter range; the maximum likelihood method is used to automatically interpret the ground orthophotos by computer to obtain Spartina alterniflora patch regions larger than a preset area threshold. The spraying rate calculation module is connected to the Spartina alterniflora patch area acquisition module, and is used to obtain the spraying rate map based on the Spartina alterniflora patch area and the normalized vegetation index. The pesticide spraying control module, connected to the spraying rate calculation module, is used for: When the area of ​​Spartina alterniflora patch is larger than a first preset area threshold, the UAV sprays the Spartina alterniflora patch area with pesticide at a preset altitude according to the spraying amount application map and the first spraying mode; the first spraying mode is spraying the mixed area of ​​Curcuma longa and Spartina alterniflora. When the area of ​​Spartina alterniflora patch is less than or equal to a first preset area threshold, the UAV sprays the Spartina alterniflora patch area with pesticide at a preset altitude according to the spraying amount application map and the second spraying mode; the second spraying mode is spraying the mixed area of ​​reeds and Spartina alterniflora. The evaluation result output module, connected to the drug spraying control module, is used for: After each spraying application, the Spartina alterniflora patch area is tracked and monitored at preset time intervals to evaluate the control effect and obtain the evaluation results. Determine whether the evaluation result is qualified; if yes, store the ground orthophoto image, the area of ​​Spartina alterniflora patch, the spraying amount map and the evaluation result; if no, execute the step of "obtaining ground orthophoto image by means of UAV aerial photography" again.

4. 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 computer program, it implements the method for identifying and controlling Spartina alterniflora as described in claim 1 or 2.

5. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the method for identifying and controlling Spartina alterniflora as described in claim 1 or 2.

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