Method and system for accounting atmospheric wet deposition nutrient flux in a designated area

Abstract

The application discloses a method and system for calculating the nutrient flux in atmospheric wet deposition in a specified area. The method takes into account the time and spatial differences of wet deposition, converts the discrete nutrient concentration data obtained by monitoring sites into a continuous nutrient concentration spatial distribution map by using the inverse distance weighting method, and then combines the corresponding rainfall spatial distribution map and the nutrient concentration spatial distribution map in the specified area to perform gridding processing. The nutrient flux in atmospheric wet deposition in the specified area is calculated according to a formula. The method can calculate the nutrient flux in atmospheric wet deposition in the area by simulating a large amount of rainfall and nutrient concentration data obtained by monitoring sites, and the calculation result is closer to the true value and the error is reduced.

Description

Technical Field

[0001] This invention belongs to the field of ecological and environmental protection, and more specifically, relates to a method and system for calculating the flux of atmospheric wet deposition nutrients in a designated area. Background Technology

[0002] Atmospheric deposition refers to the natural settling of various substances in the atmosphere, divided into dry deposition and wet deposition. Dry deposition refers to the process by which atmospheric substances settle to the ground under the influence of gravity and particulate matter adsorption when precipitation does not occur. Wet deposition refers to the process by which raindrops absorb and wash away atmospheric substances during precipitation events, including rain, snow, hail, and fog. Recent research indicates that atmospheric deposition accounts for a significant proportion of the nutrient sources in aquatic bodies, especially the deposition load of nitrogen and phosphorus, which may be comparable to the flux from land sources, thus posing a threat to aquatic ecological environment security. Currently, the nutrients transported by atmospheric wet deposition are no longer merely the main source of primary productivity for oceans, lakes, and reservoirs, but have become an external and newly added pollution load. Therefore, calculating the flux of nutrients from atmospheric wet deposition is beneficial for understanding aquatic ecological environment security issues and is of great significance for guiding the improvement of aquatic ecological environment.

[0003] Current methods for calculating atmospheric deposition nutrient fluxes based on observational approaches mostly focus on calculating deposition fluxes within a limited area. This means using a limited number of monitoring stations to represent the deposition volume (deposition intensity of a nutrient) over a small scale, without truly addressing the calculation of nutrient fluxes via wet deposition over a large area. Even when aiming to calculate nutrient deposition fluxes over a larger area, current methods rely on data from a limited number of monitoring stations. This involves continuously collecting wet deposition samples from these stations over a long period, analyzing the nutrient concentrations in the samples, and combining this with rainfall data and the corresponding underlying surface area of ​​wet deposition to estimate the total mass of nutrients entering the underlying surface via wet deposition during the observation period. This estimate is then used to represent the nutrient flux over a specified large area.

[0004] However, this calculation method fails to take into account the temporal and spatial differences in wet deposition, resulting in significant discrepancies between the calculated results and the actual values. It is difficult to objectively and accurately reflect the flux of wet deposition nutrients over a large area, and it requires the establishment of high-density continuous monitoring stations in designated areas, which is costly. Summary of the Invention

[0005] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a method and system for calculating atmospheric wet deposition nutrient fluxes within a specified area. The aim is to propose a method for calculating nutrient fluxes in atmospheric wet deposition within a specified area. This method, for the first time, converts discrete nutrient concentration data into a continuous spatial distribution map of nutrient concentrations. Then, it performs gridding processing on the spatial distribution maps of rainfall and nutrient concentrations, simulating data obtained from a sufficient number of wet deposition monitoring stations to calculate the atmospheric wet deposition nutrient fluxes within the area. This solves the technical problem that existing methods for calculating nutrient fluxes over large areas using data from individual monitoring stations, which fail to consider the temporal and spatial differences in wet deposition, easily leading to significant deviations between the calculated results and the actual values.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for calculating nutrient fluxes in atmospheric wet deposition within a specified area is provided, comprising the following steps:

[0007] (1) Obtain the spatial distribution image of rainfall corresponding to the month of calculation in the specified area, the nutrient concentration detected by the wet deposition monitoring station in the area, and the total area of ​​the underlying surface in the area;

[0008] (2) Data processing: Based on spatial difference analysis, the discrete nutrient concentration data obtained in (1) are converted into continuous data surfaces to obtain the spatial distribution map of nutrient concentration corresponding to the kernel calculation month in this region.

[0009] The spatial distribution image of rainfall corresponding to the month of kernel calculation in the specified area obtained by (1) and the spatial distribution image of nutrient concentration obtained by conversion are subjected to the same gridding process to obtain the rainfall and nutrient concentration corresponding to n simulated monitoring stations respectively.

[0010] (3) Calculate the nutrient flux Ma in atmospheric wet deposition within the specified area: Calculate according to the following formula:

[0011] Ma = ;

[0012] In the formula, The monthly rainfall (in mm) at point i, a simulated wet deposition monitoring station within the specified area; The concentration of nutrients at point i within the specified area, in mg / L / month; m is the area of ​​the underlying surface at point i within the specified region. 2 .

[0013] Preferably, the method for calculating nutrient fluxes in atmospheric wet deposition within the specified area uses an inverse distance weighting method for spatial difference analysis, converting the obtained discrete nutrient concentrations into a spatial distribution image of nutrient concentrations; the inverse distance weighting method is specifically converted according to the following formula:

[0014] Z= ,

[0015] w i =1 / d i ;

[0016] In the formula, Z represents the value of the unknown point, and w i Given the weight of point i, Z i Given the value of point i, d i Let i be the distance between the unknown point and the known point i.

[0017] Preferably, the method for calculating nutrient flux in atmospheric wet deposition within the specified area includes the inverse distance weighting method using ArcGIS or MATLAB software.

[0018] Preferably, the method for calculating nutrient fluxes in atmospheric wet deposition within the designated area includes nutrients comprising total nitrogen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, total phosphorus, reactive phosphate, and fluorine. - Cl - SO4 2- K + Na + Ca 2+ Mg 2+ One or more of the following.

[0019] According to another aspect of the present invention, a nutrient flux accounting system for atmospheric wet deposition in a designated area is also provided, which includes a data acquisition module, a data processing module and a nutrient flux accounting module.

[0020] The data acquisition module is used to acquire the spatial distribution image of rainfall in a specified area, the nutrient concentration measured at the corresponding monitoring points in the specified area, and the total area of ​​the underlying surface in that area, and submit them to the data processing module.

[0021] The data processing module converts the obtained discrete nutrient concentrations into continuous nutrient concentration spatial distribution images using the inverse distance weighting method. Then, it performs gridding processing on the obtained spatial distribution images of rainfall and nutrient concentration within the specified area to obtain rainfall and nutrient concentration data corresponding to n accounting units, and submits them to the nutrient flux accounting module.

[0022] The nutrient flux calculation module calculates the total flux of a nutrient based on the rainfall and nutrient concentration data corresponding to n calculation units of a nutrient within a specified area, specifically according to the following formula:

[0023] Ma = ;

[0024] In the formula, The monthly rainfall (in mm) at point i, a simulated wet deposition monitoring station within the specified area; The concentration of nutrients at point i within the specified area, in mg / L / month; m is the area of ​​the underlying surface at point i within the specified region. 2 .

[0025] Preferably, the nutrient flux calculation system for atmospheric wet deposition within the designated area converts discrete nutrient concentrations into a continuous spatial distribution map of nutrient concentrations, specifically according to the following conversion:

[0026] Z= ,

[0027] w i =1 / d i ;

[0028] In the formula, Z represents the value of the unknown point, and w i Given the weight of point i, Z i Given the value of point i, d i Let i be the distance between the unknown point and the known point i.

[0029] Preferably, the nutrient flux accounting system for atmospheric wet deposition within the designated area includes nutrients such as total nitrogen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, total phosphorus, reactive phosphate, and fluorine. - Cl - SO4 2- K + Na + Ca 2+ Mg 2+ One or more of the following.

[0030] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects:

[0031] The method for calculating nutrient fluxes in atmospheric wet deposition within a specified area provided by this invention involves transforming discrete monitoring point data acquired in the area into a continuous data surface using the inverse distance weighting method based on spatial analysis. This surface is then processed into a grid to simulate rainfall and nutrient concentration data acquired from a sufficient number of monitoring stations, according to the formula Ma = The method calculates the sum of atmospheric nutrient wet deposition fluxes corresponding to all simulated stations to obtain the nutrient fluxes in atmospheric wet deposition within the specified area. Because the method provided by this invention fully considers the temporal and spatial differences in atmospheric nutrient wet deposition, transforming discrete points into surfaces and then performing gridding processing, it can simulate rainfall and nutrient concentration data obtained from a sufficient number of monitoring stations. Compared with existing methods that calculate nutrient fluxes in atmospheric wet deposition over a large area based on data from individual monitoring stations, the calculation is closer to the true value. Attached Figure Description

[0032] Figure 1 This is a spatial distribution map of rainfall over land area in Xiangzhou District, Zhuhai City in March 2020.

[0033] Figure 2 This is a spatial distribution map of wet deposition nitrate concentration over land in Xiangzhou District, Zhuhai City, in March 2020.

[0034] Figure 3 This is a map showing the location of rainfall points within the land area of ​​Xiangzhou District, Zhuhai City in March 2020.

[0035] Figure 4 This is a map showing the concentration of wet deposition nitrates in the land area of ​​Xiangzhou District, Zhuhai City in March 2020. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0037] Terminology Explanation:

[0038] 1. Wet deposition refers to the process by which atmospheric substances fall onto the underlying surface (land, water, etc.) along with precipitation (rain, snow, hail, fog, etc.).

[0039] 2. Nutrients: In this invention, these mainly refer to N and P nutrients (total nitrogen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, total phosphorus, and reactive phosphate), and F... - Cl - SO4 2- K + Na + Ca 2+ Mg 2+ Inorganic ions, etc.

[0040] Currently, there are still certain difficulties in quantifying the input of nutrients such as nitrogen deposition into a designated large area via atmospheric wet deposition. This is mainly because the number of existing monitoring stations is limited, and the wet deposition flux and chemical composition of nutrients exhibit significant temporal and spatial differences. Limited monitoring data is insufficient to represent the atmospheric deposition nutrient flux over a large area. To achieve quantitative calculation of nutrient flux over a large area, it is first necessary to establish high-density continuous monitoring stations within a specific region. This would involve continuously collecting wet deposition samples from these stations over a long period, analyzing the nutrient concentrations in the samples, and finally calculating the total mass of nutrients entering the underlying surface via wet deposition during the observation period. However, establishing high-density continuous monitoring stations within a specific region is currently difficult to achieve.

[0041] This invention, by combining big data from the "National Earth System Science Data Center Shared Service Platform" and the "East Asian Acid Deposition Monitoring Network," proposes for the first time a method for calculating the flux of wet deposition nutrients when a sufficient number of wet deposition monitoring stations are deployed, as detailed below:

[0042] The spatial distribution image data of rainfall within a specified area is processed into a grid, transforming the data surface into a grid of the same size. Meanwhile, the concentrations of wet deposition nutrients measured at monitoring stations in the specified area, as well as data from relevant acid rain monitoring agencies or self-monitored data, are converted from discrete / finite concentration data into a continuous data surface based on spatial difference analysis. This simulates the spatial distribution map of wet deposition nutrient concentrations within the specified area, and then undergoes the same grid processing to refine both rainfall data and nutrient concentrations to individual calculation units (grids), theoretically enabling the deployment of a sufficient number of wet deposition monitoring stations. The wet deposition flux of each calculation unit (grid) is then calculated individually, and finally, the total wet deposition flux of nutrients in the specified area is summed. This method fully considers the temporal and spatial differences in wet deposition and, compared to existing point-based calculation methods, more objectively and realistically reflects the wet deposition flux of nutrients within a specified area.

[0043] This invention provides a method for calculating nutrient fluxes in atmospheric wet deposition within a specified area, comprising the following steps:

[0044] (1) Obtain the spatial distribution image of rainfall corresponding to the month of calculation in the specified area, the nutrient concentration detected by the monitoring stations in the area, and the total surface area A of the underlying surface in the area;

[0045] The nutrients include total nitrogen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, total phosphorus, reactive phosphate, and F. - Cl - SO4 2- K+ Na + Ca 2+ Mg 2+ One or more of the following.

[0046] In some embodiments, the nutrient concentration can be obtained by measuring the nutrient concentration at the monitoring station in the designated area or by measuring it with a relevant acid rain monitoring agency.

[0047] In some embodiments, the nutrient concentration is the monthly average concentration.

[0048] (2) Data processing: The obtained spatial distribution image of rainfall in the specified area corresponding to the month is processed into a grid to obtain rainfall data corresponding to n grids. ;

[0049] The obtained discrete nutrient concentrations are first analyzed using spatial difference to convert the discrete point measurement data into a continuous data surface, obtaining a spatial distribution map of a certain nutrient concentration for a specific month within a designated area. Then, the same gridding process is performed to simulate and measure the nutrient concentration data at n wet deposition monitoring stations. .

[0050] In some embodiments, the inverse distance weighted interpolation method in ArcGIS or MATLAB software is used to transform the discrete nutrient concentrations obtained from monitoring stations into a continuous spatial distribution map of nutrient concentrations, as detailed below:

[0051] ① Determine the weights: Determine the coordinates of the unknown and known points, calculate the distance between the unknown point and each known point, and calculate the weight w of each known point i based on the distance. i The formula is as follows:

[0052] w i =1 / d i ,

[0053] In the formula w i For weights, d i Let i be the distance between the unknown point and the known point i.

[0054] ② Calculate the value of an unknown point: Calculate the value of the unknown point based on the weights and the values ​​of known points, using the following formula:

[0055] Z=

[0056] In the formula, Z represents the value of the unknown point, and w i Given the weight of point i, Z i Let i be the value of a known point.

[0057] The above method for calculating unknown points is then used to convert discrete known points into continuous data surfaces.

[0058] (3) Calculation of wet sedimentation nutrient flux: Calculated according to the following formula:

[0059] Ma =

[0060] In the formula, Ma is the total flux of a certain nutrient through wet sedimentation in the specified area (kg / month).

[0061] The monthly rainfall (mm) at any wet deposition monitoring station i within the specified area;

[0062] The corresponding nutrient concentration (mg / L / month) at point i, the corresponding wet deposition simulation monitoring station within the specified area.

[0063] n is the total number of equally sized computational units that can be divided into the specified area, i.e., the total number of grids;

[0064] The area of ​​the underlying surface (m²) that can be represented by point i, the corresponding wet settlement simulation monitoring station, within the specified area. 2 ), which is the ratio of the total area A of the specified region to the total number of grids n.

[0065] The wet deposition nutrient concentration at each simulated monitoring point in each accounting unit is multiplied by the corresponding monthly rainfall and the corresponding underlying surface area to obtain the wet deposition nutrient flux of that accounting unit. Finally, the nutrient fluxes of all accounting units are summed to obtain the total flux of a certain nutrient in the specified area.

[0066] In some embodiments, the data processing in step (2) is specifically obtained as follows:

[0067] Using the inverse distance weighting method in ArcGIS or MATLAB software, the obtained discrete nutrient concentrations are converted into spatial distribution image maps of nutrient concentrations. Then, the obtained spatial distribution image map data of rainfall in a specified area for the calculation month and the obtained spatial distribution image map data of nutrient concentrations are converted into point file vector data with "point as the center coordinate" at a preset resolution. The attribute list of each point displays the rainfall data and wet deposition nutrient concentration data of each point. The preset resolution is the ratio of the total area of ​​the raster image map region of the specified area to the total number of calculation units n.

[0068] In addition, the present invention also provides a nutrient flux accounting system in atmospheric wet deposition within a specified area, including a data acquisition module and a data processing module;

[0069] The data acquisition module is used to acquire a spatial distribution image of rainfall within a specified area, nutrient concentrations measured at corresponding monitoring points within the specified area, and the total area of ​​the underlying surface corresponding to that area, and submit these to the data processing module; the nutrients include total nitrogen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, total phosphorus, reactive phosphate, and fluorine. - Cl - SO4 2- K + Na + Ca 2+ Mg 2+ One or more of the following.

[0070] The data processing module converts the obtained discrete nutrient concentrations into continuous nutrient concentration spatial distribution images using the inverse distance weighting method. Then, it performs gridding processing on the obtained spatial distribution images of rainfall and nutrient concentration within the specified area to obtain rainfall and nutrient concentration data corresponding to n accounting units, and submits them to the nutrient flux accounting module.

[0071] The nutrient flux calculation module calculates the total flux of a nutrient based on the rainfall and nutrient concentration data corresponding to n calculation units of a nutrient within a specified area, specifically according to the following formula:

[0072] Ma =

[0073] In the formula, Ma is the total flux of a certain nutrient through wet sedimentation in the specified area (kg / month).

[0074] The monthly rainfall (mm) at any wet deposition monitoring station i within the specified area;

[0075] The corresponding nutrient concentration (mg / L / month) at point i, the corresponding wet deposition simulation monitoring station within the specified area.

[0076] n is the total number of equally sized computational units that can be divided into the specified area, i.e., the total number of grids;

[0077] The area of ​​the underlying surface (m²) that can be represented by point i, the corresponding wet settlement simulation monitoring station, within the specified area. 2 ), which is the ratio of the total area of ​​the specified region to the total number of grids n.

[0078] The conversion of discrete nutrient concentrations into a continuous spatial distribution map of nutrient concentrations is specifically performed as follows:

[0079] Z= ,

[0080] w i =1 / d i ;

[0081] In the formula, Z represents the value of the unknown point, and w i Given the weight of point i, Z i Given the value of point i, d i Let i be the distance between the unknown point and the known point i.

[0082] The following is an example:

[0083] Example 1: Calculation of nutrient fluxes in wet deposition over the land area of ​​Xiangzhou District, Zhuhai City

[0084] This embodiment calculates the area within the land area of ​​Xiangzhou District, Zhuhai City (its area is 387.6 × 10⁻⁶). 6 m 2 Taking the nitrate flux in wet deposition in March 2020 as an example, the specific calculation steps are as follows:

[0085] (1) Obtaining the 1km resolution monthly rainfall dataset for the year to be calculated in China: Download the 2020 data (calculation year) from the 1901-2020 China 1km resolution monthly rainfall dataset from the "National Earth System Science Data Center Shared Service Platform" website, and import it into ArcGIS 10.5 software. The dataset is a raster image. Extract the spatial distribution raster image data of rainfall within the land area of ​​Xiangzhou District, Zhuhai City in March 2020 (calculation month). See details. Figure 1 .

[0086] (2) Obtain the nitrate concentration dataset for the land area of ​​Xiangzhou District, Zhuhai City in March 2020: Download the nitrate (NO3) concentration data for two monitoring stations (CNA010-xiangzhou and CNA011-zhuxiangdong) in March 2020 from the East Asian Acid Deposition Monitoring Network website (https: / / www.eanet.asia / ). - The monthly average concentration data, including the monthly average concentrations of major nutrients at two wet deposition monitoring points in Xiangzhou District, Zhuhai City, East Asia Wet Deposition Monitoring Network in 2020, are detailed in the table below.

[0087]

[0088]

[0089] Import the nitrate concentration data from the table above into ArcGIS 10.5 software. Based on the software's spatial difference analysis, and using the inverse distance weighting method, generate a raster image of the spatial distribution of nitrate wet deposition over land in Xiangzhou District, Zhuhai City in March 2020. See details below. Figure 2 .

[0090] The inverse distance weighting method is an interpolation method that uses the distance between the interpolation point and the sample point as the weight. The closer the interpolation point is to the sample point, the greater the weight is assigned. The weight is inversely proportional to the distance.

[0091] (3) Data subdivision processing: The raster image data of the spatial distribution of rainfall in the land area of ​​Xiangzhou District, Zhuhai City in March 2020 obtained in step (1) is converted into a 387.6×10 6 m 2 / 45967 is a vector data file of points centered at a specific point, where 45967 represents the number of simulated monitoring stations, i.e., the total number of grids (n) after gridding. The attribute list of each point displays the rainfall data for that point. See details Figure 3 ;

[0092] The spatial distribution raster image data of nitrate wet deposition in the land area of ​​Xiangzhou District, Zhuhai City in March 2020 obtained in step (2) was converted into a (387.6×10) layer file. 6 / 45967)m 2 This is a point file vector data at a specific resolution, centered on a single point. The attribute list for each point displays its wet deposition concentration data. See details Figure 4 .

[0093] (4) Calculate the monthly nitrate flux: According to the calculation formula Ma = Through the raster calculation function, n=45967 (387.6×10) were calculated. 6 / 45967)m 2 The sum of the wet deposition nitrate fluxes at simulated monitoring points in the accounting unit yields the wet deposition nitrate flux in the terrestrial area of ​​Xiangzhou District, Zhuhai City in March 2020, which is calculated to be 226,644 kg. This method can fundamentally optimize the limitations and variability of monitoring results from a limited number of monitoring points, and improve the accuracy of calculating atmospheric wet deposition nutrient input fluxes over large areas.

[0094] Comparative Example 1: Calculation of wet deposition nitrate flux in the terrestrial area of ​​Xiangzhou District, Zhuhai City in March 2020 using existing accounting methods.

[0095] Based on the existing accounting method, and using only the average rainfall, the average wet deposition nitrate concentration at two monitoring points, and the area, the nitrate flux within the land area of ​​Xiangzhou District, Zhuhai City in March 2020 was calculated to be 229,725 kg.

[0096] Comparing the calculation results of Example 1 above, it can be seen that the result calculated using this method is 226,644 kg, while the result calculated using the existing calculation method is 229,725 kg. Since this method can simulate a sufficient number of monitoring points and fully consider the temporal and spatial differences in wet deposition, it is reasonable to assume that the calculation result of Example 1 is closer to the true value.

[0097] As the amount of rainfall data and the number of actual monitoring points for wet deposition increase, the error of traditional methods will gradually decrease. However, even with an increase in the number of actual monitoring points for wet deposition, this method can still be used to calculate the flux of atmospheric wet deposition nutrients in a specified area.

[0098] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for calculating nutrient fluxes in atmospheric wet deposition within a specified area, characterized in that, Includes the following steps: (1) Obtain the spatial distribution map of rainfall for the month corresponding to the specified region, the concentration of nutrients detected by wet deposition monitoring stations in the region, and the total area of ​​the underlying surface corresponding to the region; (2) Data processing: Based on spatial difference analysis, the discrete nutrient concentration data obtained in (1) are converted into continuous data surfaces to obtain the spatial distribution map of nutrient concentration corresponding to the kernel calculation month in this region. The spatial distribution map of rainfall corresponding to the month of kernel calculation in the specified area obtained in (1) and the spatial distribution map of nutrient concentration obtained by conversion are subjected to the same gridding process to obtain the rainfall corresponding to n simulated monitoring stations. and nutrient concentration ; (3) Calculate the nutrient flux Ma in atmospheric wet deposition within the specified area: Calculate according to the following formula: And = ; In the formula, The monthly rainfall at point i, the simulated monitoring station for wet deposition within the specified area; The concentration of nutrients at point i within the specified area; Let be the area of ​​the underlying surface at point i within the specified region; where The unit is mm. The unit is mg / L / month. The unit is m 2 .

2. The method for calculating nutrient fluxes in atmospheric wet deposition within a specified area as described in claim 1, characterized in that, The spatial difference analysis is an inverse distance weighting method, which converts the obtained discrete nutrient concentrations into a continuous spatial distribution map of nutrient concentrations; the inverse distance weighting method is specifically converted according to the following formula: Z= ， w i =1 / d i ; In the formula, Z represents the value of the unknown point, and w i Given the weight of point i, Z i Given the value of point i, d i Let i be the distance between the unknown point and the known point i.

3. The method for calculating nutrient fluxes in atmospheric wet deposition within a specified area as described in claim 2, characterized in that, The inverse distance weighting method includes the inverse distance weighting method used in ArcGIS or MATLAB software.

4. The method for calculating nutrient fluxes in atmospheric wet deposition within a specified area as described in claim 1, characterized in that, The nutrients include total nitrogen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, total phosphorus, reactive phosphate, and F. - Cl - SO4 2- K + Na + Ca 2+ Mg 2+ One or more of the following.

5. A system for calculating nutrient fluxes in atmospheric wet deposition within a specified area, characterized in that, It includes a data acquisition module, a data processing module, and a nutrient flux calculation module; The data acquisition module is used to acquire the spatial distribution map of rainfall in the specified area, the nutrient concentration measured at the corresponding monitoring points in the specified area, and the total area of ​​the underlying surface in the specified area, and submit them to the data processing module. The data processing module converts the obtained discrete nutrient concentrations into a continuous spatial distribution map of nutrient concentrations using the inverse distance weighting method. Then, it performs gridding processing on the obtained spatial distribution maps of rainfall and nutrient concentrations within a specified area to obtain rainfall and nutrient concentration data corresponding to n accounting units, and submits them to the nutrient flux accounting module. The nutrient flux calculation module calculates the total flux of a nutrient in the specified area based on the rainfall and nutrient concentration data corresponding to each calculation unit within the specified area. The calculation is performed using the following formula: And = ; In the formula, The monthly rainfall at point i, the simulated monitoring station for wet deposition within the specified area; The concentration of nutrients at point i within the specified area; Let be the area of ​​the underlying surface at point i within the specified region; where The unit is mm. The unit is mg / L / month. The unit is m 2 .

6. The nutrient flux calculation system for atmospheric wet deposition in a designated area as described in claim 5, characterized in that, The conversion of discrete nutrient concentrations into a continuous spatial distribution map of nutrient concentrations is specifically performed as follows: Z= ， w i =1 / d i ; In the formula, Z represents the value of the unknown point, and w i Given the weight of point i, Z i Given the value of point i, d i Let i be the distance between the unknown point and the known point i.

7. The nutrient flux calculation system for atmospheric wet deposition within a designated area as described in claim 5, characterized in that, The nutrients include total nitrogen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, total phosphorus, reactive phosphate, and F. - Cl - SO4 2- K + Na + Ca 2+ Mg 2+ One or more of the following.

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