A detection method and system for monitoring plateau water body

Abstract

The present application belongs to the technical field of environmental monitoring, and discloses a detection method and system for plateau water body monitoring; comprising: acquiring lake boundary data and water system connectivity data; generating shore line segmentation numbers by segmenting the closed lake shore line according to equal arc length, and generating shore zone strip space units and lake surface grid units, and merging to build a lake space unit set; determining morphological semantics and water exchange semantics based on off-shore distance, minimum lake entry distance and lake exit distance; acquiring resident activity areas and animal activity areas and expanding to generate a disturbance buffer surface domain, and mapping shore segment disturbance semantics to the lake space unit; collecting candidate points according to morphological semantics, water exchange semantics and disturbance semantics, and iteratively selecting to obtain a final set of measurement points; the present application forms a semantic-driven measurement point selection rule by spatial unit analysis, and realizes unified measurement point layout, clear measurement point division and stronger spatial representativeness.

Description

Technical Field

[0001] This invention relates to the field of environmental monitoring technology, and more specifically, to a detection method and system for monitoring water bodies in plateau regions. Background Technology

[0002] Plateau lakes are an important component of high-altitude ecosystems, and their water conditions directly affect regional ecological security and water resource management. Due to the characteristics of the plateau environment, such as strong radiation, low temperatures, significant freeze-thaw cycles, and drastic wind field changes, key indicators of lake water quality, such as turbidity, nutrients, and dissolved oxygen, are prone to abrupt changes over time and localized aggregation and migration in space. In such scenarios, the key to monitoring work lies not in whether a single sampling is completed, but in whether, under limited operational conditions, spatially representative data that can support causal analysis can be continuously obtained.

[0003] Current monitoring of plateau lakes typically employs fixed-site or fixed-section deployment methods, setting up several monitoring points at accessible locations along the lake shore, near the lake's inlet, or near its outlet, and sampling or continuous monitoring according to a preset cycle. Some schemes expand the coverage area through static zoning or uniform grids. However, these deployment methods generally rely on experience and human judgment, lacking a technical means to deterministically analyze and map the disturbances of lake boundaries, water system connectivity, and human and animal activities into reproducible spatial units, thereby establishing stable monitoring point deployment rules.

[0004] In the absence of such deterministic spatial analysis and mapping rules, the deployment of monitoring points cannot maintain representativeness in response to the spatial migration of lake inputs, shoreline exchanges, and intra-lake mixing processes. This can easily lead to situations where monitoring points remain permanently in accessible shorelines or fixed locations, misaligning with key change zones, and unstable baseline control positions. Consequently, when monitoring indicators fluctuate, it becomes difficult to correlate these fluctuations with the spatial extent of lake inputs or shoreline disturbances, making it challenging to determine the source and impact of the fluctuations. This weakens the ability of monitoring data to support water condition diagnosis and management decisions.

[0005] In view of this, the present invention proposes a detection method and system for monitoring water bodies in plateau regions to solve the above problems. Summary of the Invention

[0006] To overcome the aforementioned deficiencies of the prior art and to achieve the above objectives, the present invention provides the following technical solution: a detection method for monitoring water bodies in plateau regions, comprising:

[0007] Acquire lake boundary data for constructing a set of lake spatial units and water system connectivity data for determining the locations of lake inlets and outlets;

[0008] Based on the closed shoreline vector, the shoreline is segmented into equal arc length segments to obtain shoreline segment numbers, and strip spatial units are generated accordingly. The lake surface area is then divided into grids to obtain a set of lake surface grid units. The strip spatial units and the set of lake surface grid units are merged to obtain a set of lake spatial units.

[0009] Calculate the distance from the shore, minimum distance into the lake, and distance out of the lake for the geometric center coordinates of the lake spatial unit, and determine the morphological semantics and water exchange semantics of the lake spatial unit accordingly.

[0010] Obtain the set of spatial objects of disturbance sources and perform isometric expansion to obtain the resident disturbance buffer region and the animal disturbance buffer region;

[0011] Based on the intersection relationship between shoreline segments and buffer zones, and combined with the determination of shoreline segment disturbance semantics in the context of the coastal neighborhood, the shoreline segment disturbance semantics are mapped to the lake spatial unit to obtain the disturbance semantics.

[0012] Based on morphological semantics, water exchange semantics, and disturbance semantics, the geometric center of the lake spatial unit is included in the candidate set, and candidate points are selected based on the maximum offshore operating distance;

[0013] Calculate the base score for the selected candidate points. Sort the candidate points from high to low according to the base score and select the first candidate point and record it in the set of selected measurement points. Then calculate the spatial proximity penalty value according to the shortest distance from the candidate point to the set of selected measurement points. Subtract it from the base score to obtain the current score. Iterate and select according to the current score to obtain the final set of measurement points.

[0014] Furthermore, the method for obtaining shoreline segment numbers by performing equal arc length segmentation on the shoreline based on the closed shoreline vector is as follows:

[0015] Among all the vertex coordinates of the closed shoreline vector, the vertex with the smallest x-coordinate is selected as the starting point of the shoreline; when there are multiple vertices with the same x-coordinate, the vertex with the smallest y-coordinate is selected as the starting point of the shoreline.

[0016] Perform equal arc length segmentation along the arc length direction of the shoreline vector, set the segment arc length as L, accumulate along the arc length from the starting point of the shoreline, when the accumulated arc length reaches L, cut off to form a shoreline segment, and clear the accumulated arc length to zero and continue to cut along the arc length direction until the segmentation of the closed shoreline is completed.

[0017] When the remaining arc length is less than L, the corresponding part of the remaining arc length is incorporated into the last shoreline segment to ensure that the shoreline segment set can completely cover the closed lake shoreline.

[0018] Starting from the beginning of the lake shoreline, the shoreline segments are assigned numbers in the order they were formed.

[0019] Furthermore, the method for generating strip-shaped spatial units is as follows:

[0020] For each shoreline segment, calculate the coordinates of the midpoint of that shoreline segment, and determine the normal direction pointing into the lake at that midpoint coordinate based on the local tangential direction of the shoreline.

[0021] A strip-shaped spatial unit is generated in the lake along the normal direction with the shoreline segment as the outer boundary. The bandwidth of the strip-shaped spatial unit is set as W. The inner and outer boundaries of the strip-shaped spatial unit are respectively composed of the shoreline segment and the equidistant line obtained by translating it along the normal direction by W.

[0022] Furthermore, the lake surface area is divided into grids to obtain a set of lake surface grid cells. The method for merging the strip-shaped spatial cells with the set of lake surface grid cells to obtain the set of lake spatial cells is as follows:

[0023] Set the grid resolution to G, and establish a regular grid covering the rectangle surrounding the lake according to the coordinate system consistent with the shoreline vector. For each grid cell, determine whether its geometric center falls within the lake surface area enclosed by the shoreline vector. If it does, record the grid cell as a lake surface grid cell and add it to the lake surface grid cell set.

[0024] By merging the set of strip spatial units with the set of lake surface grid units, and prioritizing the retention of strip spatial units in the spatially overlapping areas, a set of lake spatial units is obtained.

[0025] Furthermore, the method for obtaining morphological semantics is as follows:

[0026] When the distance from the shore of a lake spatial unit is not greater than the shoreline threshold, the lake spatial unit is determined to belong to the shoreline zone. When the distance from the shore is greater than the shoreline threshold but not greater than the transition threshold, the lake spatial unit is determined to belong to the nearshore transition zone. When the distance from the shore is greater than the transition threshold, the lake spatial unit is determined to belong to the open zone.

[0027] Furthermore, the method for obtaining water exchange semantics is as follows:

[0028] Set the radius of influence when entering the lake Mixing radius and the control radius of the lake ;

[0029] When the distance out of the lake is not greater than the lake outflow control radius When the lake spatial unit is determined to belong to the outflow control area, it will no longer be included in the determination of the inflow plume influence area and the mixing transition area.

[0030] For lake spatial units not identified as outflow control areas, when the minimum inflow distance is not greater than the inflow influence radius... When it is determined that the area belongs to the influence zone of the plume entering the lake, the minimum distance to the lake is greater than the radius of influence. and not greater than the mixing radius It is determined to belong to the mixed transition zone.

[0031] Furthermore, the method for obtaining the perturbation semantics is as follows:

[0032] For spatial objects in residential activity areas, expand them outward at equal intervals according to the resident disturbance buffer radius to generate resident disturbance buffer areas; for spatial objects in animal activity areas, expand them outward at equal intervals according to the animal disturbance buffer radius to generate animal disturbance buffer areas.

[0033] For each shoreline segment, determine whether its geometry intersects with the resident disturbance buffer area. If it intersects, mark the shoreline segment as a resident disturbance semantic. Determine whether its geometry intersects with the animal disturbance buffer area. If it intersects, mark the shoreline segment as an animal disturbance semantic. When the shoreline segment satisfies both types of intersection conditions, retain both resident disturbance semantic and animal disturbance semantic.

[0034] For shoreline segments affected by residents and those affected by animals, a shoreline neighborhood determination is performed. Shoreline segments with a shoreline arc length not greater than the shoreline neighborhood threshold are marked as effective affected shoreline segments, while shoreline segments with a shoreline arc length greater than the shoreline neighborhood threshold are marked as potential disturbed shoreline segments. When a shoreline segment does not intersect with either the resident disturbance buffer zone or the animal disturbance buffer zone and its shoreline arc length is greater than the shoreline neighborhood threshold, the shoreline segment is marked as an uninhabited baseline shoreline segment, and the disturbance semantics of the shoreline segment are mapped to the lake spatial unit.

[0035] Furthermore, the method for obtaining the base score is as follows:

[0036] For candidate sites of impact on residents and candidate sites of impact on animals, a basic score is obtained by weighting the effectiveness level of entry into the lake and the disturbance intensity level according to a preset weight.

[0037] For candidate sites for plumes entering the lake and candidate sites for mixed transition, the effectiveness level of entering the lake will be used as the base score.

[0038] For candidate control points for the lake outflow and reference candidate points for the center of the open area, the distance from the shore is used as the basic score.

[0039] For unmanned baseline candidate points, the disturbance intensity level is set to 0 as a hard condition and the offshore distance is used as the base score.

[0040] Furthermore, the iterative selection method is as follows:

[0041] In the candidate set, the first candidate point is selected and added to the set of selected measurement points by sorting the basic scores from high to low.

[0042] After adding a candidate point to the selected test point set, calculate the Euclidean distance between the candidate point and each test point in the selected test point set that has not yet been selected in the same candidate set, and take the minimum value as the closest distance. Calculate the spatial proximity penalty value based on the closest distance, deduct the spatial proximity penalty value from the base score to obtain the current score, and then select the next candidate point to be added to the selected test point set according to the current score from high to low, until the number of candidate points added to the selected test point set reaches the test point role quota corresponding to the candidate set.

[0043] A detection system for monitoring water bodies in high-altitude areas, used to implement the aforementioned detection method for monitoring water bodies in high-altitude areas, includes:

[0044] Data acquisition module: Acquires lake boundary data for constructing a set of lake spatial units and water system connectivity data for determining the locations of lake inlets and outlets;

[0045] Spatial Unit Division Module: Based on the closed shoreline vector, the shoreline is divided into equal arc length segments to obtain shoreline segment numbers, and strip spatial units are generated accordingly. The lake surface area is divided into grids to obtain a set of lake surface grid units. The strip spatial units and the set of lake surface grid units are merged to obtain a set of lake spatial units.

[0046] Semantic determination module: Calculates the distance from the shore, minimum distance into the lake, and distance out of the lake for the geometric center coordinates of the lake spatial unit, and determines the morphological semantics and water exchange semantics of the lake spatial unit accordingly;

[0047] Disturbance buffer generation module: Obtains a set of spatial objects of disturbance sources and performs equidistant expansion to obtain the resident disturbance buffer region and the animal disturbance buffer region;

[0048] Disturbance semantic acquisition module: Based on the intersection relationship between shoreline segments and buffer areas and combined with the coastal neighborhood, the disturbance semantics of shoreline segments are marked and mapped to lake spatial units to obtain disturbance semantics;

[0049] Candidate site selection module: Based on morphological semantics, water exchange semantics and disturbance semantics, the geometric center of the lake spatial unit is included in the candidate set, and candidate sites are selected based on the maximum offshore operating distance;

[0050] Iterative point selection output module: Calculate the basic score for the selected candidate points, sort the candidate points from high to low according to the basic score, select the first candidate point and record it in the selected measurement point set, calculate the spatial proximity penalty value according to the closest distance from the candidate point to the selected measurement point set, deduct it from the basic score to obtain the current score, and iteratively select the final measurement point set according to the current score.

[0051] The technical effects and advantages of the detection method and system for monitoring water bodies in plateau regions proposed in this invention are as follows:

[0052] First, this invention constructs a unified spatial representation based on lake boundary data and water system connectivity data. It obtains shoreline segment numbers by segmenting closed shoreline vectors into equal arc lengths, and merges strip-shaped spatial units with lake surface grid units to form a set of lake spatial units. This transforms the nearshore and surface areas of the lake into reproducible discrete spatial units, thereby providing a deterministic analytical basis for the layout of measurement points and avoiding the inconsistent layout rules and difficulty in reproducibility caused by existing technologies that rely on experience and manual judgment.

[0053] Secondly, this invention determines morphological and water exchange semantics based on the distance from the shore, the minimum distance into the lake, and the distance out of the lake in the set of lake spatial units. It also generates a buffer zone for resident disturbance and a buffer zone for animal disturbance based on the set of spatial objects of disturbance sources. Combined with the determination of shoreline segment disturbance semantics by the neighboring area, it maps the disturbance to the lake spatial units, so that the impact of inflow, mixing and transition, outflow control and disturbance can fall into the same spatial semantic system, thereby improving the ability to identify the source and range of influence of indicator fluctuations.

[0054] Furthermore, this invention aggregates candidate sets according to role templates and combines them with offshore reachability to filter and output feasible candidate locations. Then, through iterative selection of basic scores and spatial proximity penalty values, a final set of measurement points is formed. This ensures that the measurement point system takes into account both critical process areas and baseline control areas and avoids excessive clustering, thereby continuously obtaining spatially representative data that can be used for cause determination under constrained operating conditions.

[0055] In summary, this invention achieves the technical effects of unified and reproducible measurement point layout, stronger spatial representativeness, and more sufficient support for cause discrimination by constructing spatial units deterministically, determining semantics and perturbation mapping, and selecting points by role and iteratively clustering. Attached Figure Description

[0056] Figure 1 This is a flowchart of a detection method for monitoring water bodies in plateau regions, as described in Embodiment 1 of the present invention.

[0057] Figure 2 This is a schematic diagram illustrating the method for incorporating the geometric center of a lake spatial unit into a candidate set in Embodiment 1 of the present invention.

[0058] Figure 3 This is a module diagram of a detection system for monitoring water bodies in plateau regions, as shown in Embodiment 2 of the present invention. Detailed Implementation

[0059] 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.

[0060] Example 1

[0061] See Figure 1 As shown in the figure, this embodiment provides a detection method for monitoring water bodies in plateau regions, including:

[0062] Obtain the lake boundary data of the target lake.

[0063] The lake boundary data includes a closed shoreline vector, lake surface area parameters, and coordinate system information consistent with the shoreline vector.

[0064] Obtain water system connectivity data to determine the locations of the lake inlet and outlet.

[0065] The water system connectivity data includes the centerline of the tributary flowing into the lake, the coordinates of the intersection of the tributary and the shoreline, the centerline of the outlet channel, and the coordinates of the intersection of the outlet channel and the shoreline.

[0066] When acquiring lake boundary data of the target lake, the coordinates of shoreline measurement points are collected sequentially along the actual waterline of the target lake using on-site measurement. The coordinates of the shoreline measurement points are output by the global satellite positioning equipment and numbered in order of shoreline direction.

[0067] The coordinates of the shoreline measurement points are closed and connected to form a closed shoreline vector. The coordinate system information corresponding to the global satellite positioning equipment is recorded as the coordinate system information consistent with the shoreline vector.

[0068] The area of ​​the closed polygon is calculated based on the closed shoreline vector and recorded as the lake surface area parameter.

[0069] When acquiring water system connectivity data to determine the locations of lake inlets and outlets, on-site measurements are used to identify inflow tributaries and outflow channels connecting to the lake during shoreline patrols. Intersection coordinates are collected at the intersection of each inflow tributary and the shoreline, and at the intersection of each outflow channel and the shoreline. These intersection coordinates are output by a global positioning system. The intersection coordinates corresponding to the intersection of each inflow tributary and the shoreline are defined as the inlet coordinates, and the intersection coordinates corresponding to the intersection of each outflow channel and the shoreline are defined as the outlet coordinates, thus obtaining the inlet coordinate set and the outlet coordinate set.

[0070] The coordinates of the centerline measurement points are collected sequentially along the river centerline of each tributary flowing into the lake and the outlet channel, and then connected to generate the centerline of the tributary flowing into the lake and the centerline of the outlet channel. This yields water system connectivity data including the centerline of the tributary flowing into the lake, the coordinates of the intersection of the tributary flowing into the lake and the shoreline, the centerline of the outlet channel, and the coordinates of the intersection of the outlet channel and the shoreline.

[0071] Among all the vertex coordinates of the closed shoreline vector, the vertex with the smallest x-coordinate is selected as the starting point of the shoreline; when there are multiple vertices with the same x-coordinate, the vertex with the smallest y-coordinate is selected as the starting point of the shoreline.

[0072] Perform equal arc length segmentation along the arc length direction of the shoreline vector, set the segment arc length as L, accumulate along the arc length from the starting point of the shoreline, when the accumulated arc length reaches L, cut off to form a shoreline segment, and clear the accumulated arc length to zero and continue to cut along the arc length direction until the segmentation of the closed shoreline is completed.

[0073] When the remaining arc length is less than L, the corresponding part of the remaining arc length is incorporated into the last shoreline segment to ensure that the shoreline segment set can completely cover the closed lake shoreline.

[0074] Starting from the beginning of the lake shoreline, the shoreline segments are assigned numbers in the order they were formed.

[0075] For each shoreline segment, calculate the coordinates of the midpoint of that shoreline segment, and determine the normal direction pointing into the lake at that midpoint coordinate based on the local tangential direction of the shoreline.

[0076] Using shoreline segments as outer boundaries, strip-shaped spatial units are generated inward along the normal direction into the lake. The bandwidth of the strip-shaped spatial unit is set to W. The inner and outer boundaries of the strip-shaped spatial unit are respectively composed of shoreline segments and equidistant lines obtained by translating them along the normal direction by W. The lake shore neighborhood is transformed into a discrete spatial unit that can be used for semantic determination.

[0077] It should be noted that, based on the total circumference of the closed shoreline, the shoreline is divided into N equal segments, and the segment arc length L is taken as the corresponding equal arc length; where N is preferably 100 to 150.

[0078] The bandwidth W of the strip-shaped spatial unit is preferably set according to the maximum offshore operating distance, taking 5% to 15% of the maximum offshore operating distance. As an optional engineering range, W is 30m to 500m. The maximum offshore operating distance is calculated from the set of offshore distances that were successfully sampled in historical sampling operation records, and the highest quantile, for example, 90%, is taken as the maximum offshore operating distance.

[0079] The lake surface area is divided into grids. The grid resolution is set to G. A regular grid covering the outer rectangle of the lake is established according to the coordinate system consistent with the shoreline vector. For each grid cell, it is determined whether its geometric center falls within the lake surface area surrounded by the shoreline vector. If it does, the grid cell is recorded as a lake surface grid cell and added to the lake surface grid cell set.

[0080] The grid resolution G is preferably set after the bandwidth W is determined, such that the bandwidth direction contains 3 to 8 grid cells. As an optional engineering range, G is 10m / pixel to 100m / pixel.

[0081] By merging the set of strip spatial units with the set of lake surface grid units, and prioritizing the retention of strip spatial units in the spatially overlapping areas, a set of lake spatial units is obtained.

[0082] For a strip-shaped spatial unit, the segment number of the shoreline segment corresponding to the strip-shaped spatial unit is defined as the shoreline segment number of the strip-shaped spatial unit; for a lake surface grid unit, the geometric center coordinates of the lake surface grid unit are first used as the representative point of the lake surface grid unit; the shortest distance from the representative point to each shoreline segment is calculated segment by segment on the closed lake shoreline vector, and the shoreline segment corresponding to the shortest distance is taken as the nearest shoreline segment; the segment number of the nearest shoreline segment is defined as the shoreline segment number of the lake surface grid unit.

[0083] For each lake spatial unit, a unit number is generated and its geometric center coordinates and the number of its shoreline segment are recorded. This enables the set of spatial units to serve as a unified input for subsequent spatial semantic analysis, thereby achieving a deterministic expression of the spatial positional relationships of the lake water body.

[0084] After completing the construction of the lake spatial unit set, obtain the set of disturbance source spatial objects.

[0085] The set of disturbance source spatial objects includes spatial objects of residential activity areas and spatial objects of animal activity areas.

[0086] The method for obtaining the set of disturbance source spatial objects is as follows:

[0087] A field patrol was conducted along the lake shoreline and the pre-defined patrol area outside the lake shore. When areas with concentrated residential activity were found, the coordinates of the inflection points at the outer edge of the area were used as measurement points. These inflection points were then sequentially collected using GPS and connected to form closed polygons, which were recorded as spatial objects of the residential activity area. When areas with concentrated animal activity or animal wading activity were found, the outer edge of areas with high density of animal activity traces or wading shallows was used as the measurement boundary. Similarly, the coordinates of the boundary inflection points were collected using GPS and connected to form closed polygons, which were recorded as spatial objects of the animal activity area. The coordinates of the spatial objects of the residential and animal activity areas were uniformly transformed to a unified coordinate system consistent with the lake shoreline vector and recorded as a set of disturbance source spatial objects.

[0088] It should be noted that during on-site inspections, evidence of resident activity includes fixed campsites, cooking traces, garbage dumps, vehicle parking spots, temporary boardwalks, or nodes with obvious trampling paths; evidence of animal activity includes areas with high density of footprints, feces accumulation points, watering and trampling areas, and hair residue points; the boundary of wading activity areas is determined by the visible water-land boundary line or continuous trampling area at the outer edge of the wading shallows.

[0089] Establish the relationship between the shoreline segments of each lake spatial unit.

[0090] The area centroid of each lake spatial unit is taken as the geometric center, and the shortest distance from the geometric center to the shoreline vector is calculated and denoted as the distance from the shore.

[0091] Calculate the shortest distance from the geometric center to the coordinates of each lake inlet and take the minimum value as the minimum distance into the lake. Calculate the shortest distance from the geometric center to the coordinates of the lake outlet and take it as the distance out of the lake.

[0092] The method for establishing the segmented association relationship of the unit shoreline is as follows:

[0093] For each lake spatial unit, the point on the shoreline vector that has the smallest Euclidean distance to the geometric center of the lake spatial unit is taken as the nearest shoreline point.

[0094] Determine the shoreline segment number into which the nearest shoreline point falls, and record this shoreline segment number as the shoreline segment number of the lake spatial unit.

[0095] For open area lake spatial units, the shoreline segment number field of the lake spatial unit is left empty to avoid assigning shoreline disturbance semantics to the open area lake spatial units.

[0096] The morphological semantics of lake spatial units are obtained, including the shore zone, nearshore transition zone and open zone.

[0097] The method for obtaining the morphological semantics is as follows:

[0098] When the distance from the shore of a lake spatial unit is not greater than the shoreline threshold, the lake spatial unit is determined to belong to the shoreline zone. When the distance from the shore is greater than the shoreline threshold but not greater than the transition threshold, the lake spatial unit is determined to belong to the nearshore transition zone. When the distance from the shore is greater than the transition threshold, the lake spatial unit is determined to belong to the open zone.

[0099] The shoreline threshold and transition threshold are derived from the lake characteristic length Lc and are constrained by the maximum offshore operating distance. The shoreline threshold can be selected from 0.03Lc to 0.08Lc, and the transition threshold can be selected from 0.10Lc to 0.25Lc, where the lake characteristic length Lc is taken as the square root of the lake surface area parameter.

[0100] The water exchange semantics of a lake spatial unit are obtained, which includes the inflow plume influence zone, the mixing transition zone, and the outflow control zone.

[0101] The method for obtaining water exchange semantics is as follows:

[0102] Set the radius of influence when entering the lake Mixing radius and the control radius of the lake ;

[0103] When the distance out of the lake is not greater than the lake outflow control radius When the lake spatial unit is determined to belong to the outflow control area, it will no longer be included in the determination of the inflow plume influence area and the mixing transition area.

[0104] For lake spatial units not identified as outflow control areas, when the minimum inflow distance is not greater than the inflow influence radius... When it is determined that the area belongs to the influence zone of the plume entering the lake, the minimum distance to the lake is greater than the radius of influence. and not greater than the mixing radius It is determined to belong to the mixed transition zone.

[0105] Among them, the preferred ones are Take 0.03 Its value is limited to not less than the lake surface grid resolution G and not greater than 0.6 times the maximum offshore operating distance. Take 0.10 It is stipulated that its value shall not be less than 2G and not greater than 0.8 times the maximum offshore operating distance. Take 0.03 It is stipulated that its value shall not be less than G and not greater than 0.6 times the maximum offshore operating distance.

[0106] After completing the morphological semantics and water exchange semantics determination, the disturbance semantics of the lake spatial unit are obtained. The disturbance semantics include resident disturbance semantics, animal disturbance semantics and unmanned baseline semantics.

[0107] Perturbation semantics is used to reflect the likelihood that the shoreline corresponding to a lake spatial unit will be affected by human or animal activities and its suitability as a baseline.

[0108] The method for obtaining the perturbation semantics is as follows:

[0109] First, expand the spatial objects in the residential activity area outward at equal intervals according to the resident disturbance buffer radius to generate the resident disturbance buffer area; then expand the spatial objects in the animal activity area outward at equal intervals according to the animal disturbance buffer radius to generate the animal disturbance buffer area.

[0110] For each shoreline segment, determine whether its geometry intersects with the resident disturbance buffer region. If it intersects, mark the shoreline segment as a resident disturbance semantic. Determine whether its geometry intersects with the animal disturbance buffer region. If it intersects, mark the shoreline segment as an animal disturbance semantic. When the shoreline segment satisfies both types of intersection conditions, retain both resident disturbance semantic and animal disturbance semantic.

[0111] The buffer radius for resident disturbance and the buffer radius for animal disturbance are determined using a derived setting method based on the lake surface grid resolution G.

[0112] The buffer radius for resident disturbance is set to k1×G, and the buffer radius for animal disturbance is set to k2×G, where k1 and k2 are configurable multiples and their values ​​are not less than 1. Preferably, k1 and k2 are 2 to 6, so that the buffer area covers at least several adjacent lake spatial units without excessive expansion.

[0113] To avoid misclassifying shorelines that are close to the disturbance source but unlikely to have an impact on the lake as affected shorelines based solely on straight intersections, the classification of shorelines affected by residents and animals is further supplemented by the determination of the coastal neighborhood.

[0114] The method for determining the coastal neighborhood is as follows:

[0115] Starting from the beginning of the shoreline, the total arc length of the shoreline is obtained by accumulating the arc lengths along the closed shoreline vector in order of the vertices.

[0116] The midpoint of the arc length of each shoreline segment is taken as the representative point of the segment.

[0117] Calculate the cumulative arc length along the shoreline between the representative point of the segment and the coordinates of the lake inlet. Compare the cumulative arc length with the arc length obtained by subtracting the cumulative arc length from the total arc length around the lake. Take the smaller one as the distance along the shoreline from the lake inlet.

[0118] For the same shoreline segment, traverse each lake inlet and take the smallest arc distance along the shoreline as the arc distance to the nearest lake inlet; when the intersection of the lake inlets falls within the range of the corresponding arc segment of the shoreline segment, the arc distance along the shoreline is directly taken as 0.

[0119] When the distance of the coastal arc length is not greater than the coastal neighborhood threshold, the coastline segment is marked as an effective influencing coastline segment; when the distance of the coastal arc length is greater than the coastal neighborhood threshold, the coastline segment is marked as a potential disturbance coastline segment.

[0120] When a shoreline segment does not intersect with either the resident disturbance buffer zone or the animal disturbance buffer zone, and the shoreline arc length distance from the shoreline segment to the nearest lake inlet is greater than the shoreline neighborhood threshold, the shoreline segment is marked as an uninhabited baseline shoreline segment.

[0121] The coastal neighborhood threshold is determined by professionals in this industry based on historical or test data. The threshold is selected by taking the shoreline sections with obvious external input characteristics near the lake inlet as positive samples and the shoreline sections far from the lake inlet with stable indicators as negative samples. Different coastal neighborhood thresholds are explored to select the threshold that can maximize the distinction between positive and negative samples.

[0122] After completing the shoreline disturbance semantic labeling, the shoreline number of each lake spatial unit is mapped to the disturbance semantic label of the corresponding shoreline, thereby assigning disturbance semantics to each lake spatial unit.

[0123] After assigning a disturbance semantic to each lake spatial unit, the lake inflow effectiveness level and disturbance intensity level of that lake spatial unit are calculated.

[0124] The method for obtaining the lake entry effectiveness level is as follows:

[0125] When the water exchange semantic category of a lake spatial unit is the lake plume influence zone or the mixing transition zone, the lake inflow effectiveness level of the lake spatial unit is set to 2.

[0126] When the water exchange semantic category of a lake spatial unit does not belong to the inflow plume influence zone and the mixing transition zone, but its shoreline segment is marked as an effective influence shoreline segment, the inflow effectiveness level of the lake spatial unit is set to 1.

[0127] The inflow effectiveness level for the remaining lake spatial units is set to 0.

[0128] The method for obtaining the disturbance intensity level is as follows:

[0129] Taking each shoreline segment as the center, the shoreline neighborhood is expanded to both sides according to the shoreline neighborhood threshold to form the shoreline neighborhood range, and the shoreline statistical width is expanded to the land side to form the shoreline segment statistical area, where the shoreline statistical width is the larger value between the resident disturbance buffer radius and the animal disturbance buffer radius.

[0130] The number of disturbance source spatial objects n falling within the statistical area of ​​this shoreline is counted. The disturbance source spatial objects include spatial objects in residential activity areas and spatial objects in animal activity areas. n is then mapped to disturbance intensity levels.

[0131] Specifically, when n is 0, the disturbance intensity level is 0; when n is 1 to 2, the disturbance intensity level is 1; when n is 3 to 5, the disturbance intensity level is 2; and when n is greater than 5, the disturbance intensity level is 3.

[0132] The disturbance intensity level of the shoreline segment is mapped to the associated lake spatial unit through the shoreline segment number to obtain the disturbance intensity level of the lake spatial unit.

[0133] See Figure 2 As shown, the geometric center coordinates of the lake spatial unit are used as the candidate point coordinates corresponding to the lake spatial unit, and they are assigned to different candidate sets according to the role template.

[0134] The method for categorizing candidates into different candidate sets based on role templates is as follows:

[0135] When the water exchange semantic category of a lake spatial unit is the lake plume influence area and the lake inflow effectiveness level is 2, the candidate points are included in the lake plume candidate set.

[0136] When the water exchange semantic category is mixed transition zone and the morphological semantic category is nearshore transition zone, the candidate points are assigned to the mixed transition candidate set.

[0137] When the semantic category of water exchange is the outflow control area, the candidate points are assigned to the outflow control candidate set.

[0138] When the morphological semantic category is open area and the water exchange semantic category is not lake outflow control area, the candidate points are assigned to the open area central reference candidate set.

[0139] When the perturbation semantic category is unmanned baseline semantics, the lake entry validity level is 0, and the morphological semantic category is not open area, the candidate points are included in the unmanned baseline candidate set.

[0140] When the disturbance semantic category includes resident disturbance semantics, the lake entry effectiveness level is not less than 1, and the morphological semantic category is shoreline area, the candidate points will be included in the resident impact candidate set.

[0141] When the disturbance semantic category includes animal disturbance semantics, the lake entry effectiveness level is not less than 1, and the morphological semantic category is shoreline area, the candidate site will be included in the animal influence candidate set.

[0142] After the candidate set is collected, the candidate points are subjected to feasible constraint screening to output the final set of measurement points.

[0143] Obtain the set of coordinates of the shoreline landing points and the maximum offshore working distance.

[0144] The method for obtaining the set of coordinates of the shoreline landing points is as follows:

[0145] On-site patrols along the lake shoreline identify locations where mooring or entry into the water is possible. At each landing location, GPS coordinates are collected and numbered to form a set of landing point coordinates along the shoreline.

[0146] The maximum offshore distance from which sampling can be completed is determined based on historical sampling operation records, and this distance is used as the maximum offshore operation distance.

[0147] Offshore reachability determination is performed on candidate locations in each candidate set.

[0148] The method for determining offshore reachability is as follows:

[0149] For each candidate point, calculate its straight-line distance to each landable point in the set of coordinates of landable points on the shoreline, and take the minimum value as the minimum landing distance; when the minimum landing distance is not greater than the maximum offshore working distance, retain the candidate point; when the minimum landing distance is greater than the maximum offshore working distance, remove the candidate point.

[0150] Lightweight scoring and iterative selection are performed on candidate sites that have passed offshore accessibility assessment to meet the site role quota and avoid overcrowding of sites.

[0151] Obtain the base score for each candidate point.

[0152] The basic score is obtained as follows:

[0153] For candidate sites impacting residents and animals, a base score is obtained by weighting the lake entry effectiveness level and disturbance intensity level according to preset weights. The weight of the lake entry effectiveness level can be selected as 0.6, and the weight of the disturbance intensity level can be selected as 0.4. For candidate sites for plume entering the lake and mixed transition sites, the lake entry effectiveness level is used as the base score. For candidate sites for lake exit control and open area center reference sites, the distance from the shore is used as the base score. For candidate sites for uninhabited baselines, the disturbance intensity level is set to 0 as a hard condition, and the distance from the shore is used as the base score.

[0154] Perform iterative selection on each candidate set and output the set of selected measurement points.

[0155] The iterative selection method is as follows:

[0156] In a candidate set, the first candidate point is selected and added to the set of selected measurement points by sorting the basic scores from high to low.

[0157] After adding a candidate point to the selected test point set, calculate the Euclidean distance between the candidate point and each test point in the selected test point set that has not yet been selected in the same candidate set, and take the minimum value as the closest distance. Calculate the spatial proximity penalty value based on the closest distance, deduct the spatial proximity penalty value from the base score to obtain the current score, and then select the next candidate point to be added to the selected test point set according to the current score from high to low, until the number of candidate points added to the selected test point set reaches the test point role quota corresponding to the candidate set.

[0158] It should be noted that the current rating can be negative.

[0159] The method for obtaining the spatial proximity penalty value is as follows:

[0160] The penalty distance boundary is derived from the lake surface grid resolution G. The first distance boundary is 3G and the second distance boundary is 1.5G. When the nearest distance is not less than 3G, the spatial proximity penalty value is 0. When the nearest distance is between 1.5G and 3G, the spatial proximity penalty value is 1. When the nearest distance is less than 1.5G, the spatial proximity penalty value is 3.

[0161] The final set of measuring points is generated according to the measuring point role quota order.

[0162] The order of the measurement point role quotas is as follows:

[0163] First, select one plume entry point from the plume entry candidate set for each major inlet; then select one mixing transition point from the corresponding mixing transition candidate set.

[0164] Then select one outflow control point from the candidate set of outflow control points;

[0165] Then select an open area center reference point from the open area center reference candidate set;

[0166] Then select an unmanned baseline point from the unmanned baseline candidate set;

[0167] When there are still points remaining in the budget, additional points are selected from the candidate sets of resident impacts and animal impacts respectively using an iterative selection method.

[0168] Output the final set of measurement points.

[0169] Example 2

[0170] See Figure 3 As shown, this embodiment provides a detection system for monitoring water bodies in high-altitude areas, used to implement the aforementioned detection method for monitoring water bodies in high-altitude areas, including:

[0171] Data acquisition module: Acquires lake boundary data for constructing a set of lake spatial units and water system connectivity data for determining the locations of lake inlets and outlets;

[0172] Spatial Unit Division Module: Based on the closed shoreline vector, the shoreline is divided into equal arc length segments to obtain shoreline segment numbers, and strip spatial units are generated accordingly. The lake surface area is divided into grids to obtain a set of lake surface grid units. The strip spatial units and the set of lake surface grid units are merged to obtain a set of lake spatial units.

[0173] Semantic determination module: Calculates the distance from the shore, minimum distance into the lake, and distance out of the lake for the geometric center coordinates of the lake spatial unit, and determines the morphological semantics and water exchange semantics of the lake spatial unit accordingly;

[0174] Disturbance buffer generation module: Obtains a set of spatial objects of disturbance sources and performs equidistant expansion to obtain the resident disturbance buffer region and the animal disturbance buffer region;

[0175] Disturbance semantic acquisition module: Based on the intersection relationship between shoreline segments and buffer areas and combined with the coastal neighborhood, the disturbance semantics of shoreline segments are marked and mapped to lake spatial units to obtain disturbance semantics;

[0176] Candidate site selection module: Based on morphological semantics, water exchange semantics and disturbance semantics, the geometric center of the lake spatial unit is included in the candidate set, and candidate sites are selected based on the maximum offshore operating distance;

[0177] Iterative point selection output module: Calculate the basic score for the selected candidate points, sort the candidate points from high to low according to the basic score, select the first candidate point and record it in the selected measurement point set, calculate the spatial proximity penalty value according to the closest distance from the candidate point to the selected measurement point set, deduct it from the basic score to obtain the current score, and iteratively select the final measurement point set according to the current score.

[0178] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0179] In conclusion, 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, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A detection method for monitoring water bodies in plateau regions, characterized in that, include: Acquire lake boundary data for constructing a set of lake spatial units and water system connectivity data for determining the locations of lake inlets and outlets; Based on the closed shoreline vector, the shoreline is segmented into equal arc length segments to obtain shoreline segment numbers, and strip spatial units are generated accordingly. The lake surface area is then divided into grids to obtain a set of lake surface grid units. The strip spatial units and the set of lake surface grid units are merged to obtain a set of lake spatial units. Calculate the distance from the shore, minimum distance into the lake, and distance out of the lake for the geometric center coordinates of the lake spatial unit, and determine the morphological semantics and water exchange semantics of the lake spatial unit accordingly. Obtain the set of spatial objects of disturbance sources and perform isometric expansion to obtain the resident disturbance buffer region and the animal disturbance buffer region; Based on the intersection relationship between shoreline segments and buffer zones, and combined with the determination of shoreline segment disturbance semantics in the context of the coastal neighborhood, the shoreline segment disturbance semantics are mapped to the lake spatial unit to obtain the disturbance semantics. Based on morphological semantics, water exchange semantics, and disturbance semantics, the geometric center of the lake spatial unit is included in the candidate set, and candidate points are selected based on the maximum offshore operating distance; Calculate the base score for the selected candidate points. Sort the candidate points from high to low according to the base score and select the first candidate point and record it in the set of selected measurement points. Then calculate the spatial proximity penalty value according to the shortest distance from the candidate point to the set of selected measurement points. Subtract it from the base score to obtain the current score. Iterate and select according to the current score to obtain the final set of measurement points.

2. The detection method for monitoring water bodies in plateau regions according to claim 1, characterized in that, The method for obtaining shoreline segment numbers by performing equal arc length segmentation on the shoreline based on the closed shoreline vector is as follows: Among all the vertex coordinates of the closed shoreline vector, the vertex with the smallest x-coordinate is selected as the starting point of the shoreline; when there are multiple vertices with the same x-coordinate, the vertex with the smallest y-coordinate is selected as the starting point of the shoreline. Perform equal arc length segmentation along the arc length direction of the shoreline vector, set the segment arc length as L, accumulate along the arc length from the starting point of the shoreline, when the accumulated arc length reaches L, cut off to form a shoreline segment, and clear the accumulated arc length to zero and continue to cut along the arc length direction until the segmentation of the closed shoreline is completed. When the remaining arc length is less than L, the corresponding part of the remaining arc length is incorporated into the last shoreline segment to ensure that the shoreline segment set can completely cover the closed lake shoreline. Starting from the beginning of the lake shoreline, the shoreline segments are assigned numbers in the order they were formed.

3. The detection method for monitoring water bodies in plateau regions according to claim 1, characterized in that, The method for generating strip-shaped spatial units is as follows: For each shoreline segment, calculate the coordinates of the midpoint of that shoreline segment, and determine the normal direction pointing into the lake at that midpoint coordinate based on the local tangential direction of the shoreline. A strip-shaped spatial unit is generated in the lake along the normal direction with the shoreline segment as the outer boundary. The bandwidth of the strip-shaped spatial unit is set as W. The inner and outer boundaries of the strip-shaped spatial unit are respectively composed of the shoreline segment and the equidistant line obtained by translating it along the normal direction by W.

4. The detection method for monitoring water bodies in plateau regions according to claim 1, characterized in that, The method for performing grid-based subdivision of the lake surface area to obtain a set of lake surface grid cells, and then merging the strip spatial cells with the set of lake surface grid cells to obtain a set of lake spatial cells is as follows: Set the grid resolution to G, and establish a regular grid covering the rectangle surrounding the lake according to the coordinate system consistent with the shoreline vector. For each grid cell, determine whether its geometric center falls within the lake surface area enclosed by the shoreline vector. If it does, record the grid cell as a lake surface grid cell and add it to the lake surface grid cell set. By merging the set of strip spatial units with the set of lake surface grid units, and prioritizing the retention of strip spatial units in the spatially overlapping areas, a set of lake spatial units is obtained.

5. The detection method for monitoring water bodies in plateau regions according to claim 1, characterized in that, The method for obtaining the morphological semantics is as follows: When the distance from the shore of a lake spatial unit is not greater than the shoreline threshold, the lake spatial unit is determined to belong to the shoreline zone. When the distance from the shore is greater than the shoreline threshold but not greater than the transition threshold, the lake spatial unit is determined to belong to the nearshore transition zone. When the distance from the shore is greater than the transition threshold, the lake spatial unit is determined to belong to the open zone.

6. The detection method for monitoring water bodies in plateau regions according to claim 1, characterized in that, The method for obtaining the water exchange semantics is as follows: Set the radius of influence when entering the lake Mixing radius and the control radius of the lake ; When the distance out of the lake is not greater than the lake outflow control radius When the lake spatial unit is determined to belong to the outflow control area, it will no longer be included in the determination of the inflow plume influence area and the mixing transition area. For lake spatial units not identified as outflow control areas, when the minimum inflow distance is not greater than the inflow influence radius... When it is determined that the area belongs to the influence zone of the plume entering the lake, the minimum distance to the lake is greater than the radius of influence. and not greater than the mixing radius It is determined to belong to the mixed transition zone.

7. The detection method for monitoring water bodies in plateau regions according to claim 1, characterized in that, The method for obtaining the perturbation semantics is as follows: For spatial objects in residential activity areas, expand them outward at equal intervals according to the resident disturbance buffer radius to generate resident disturbance buffer areas; for spatial objects in animal activity areas, expand them outward at equal intervals according to the animal disturbance buffer radius to generate animal disturbance buffer areas. For each shoreline segment, determine whether its geometry intersects with the resident disturbance buffer area. If it intersects, mark the shoreline segment as a resident disturbance semantic. Determine whether its geometry intersects with the animal disturbance buffer area. If it intersects, mark the shoreline segment as an animal disturbance semantic. When the shoreline segment satisfies both types of intersection conditions, retain both resident disturbance semantic and animal disturbance semantic. For shoreline segments affected by residents and those affected by animals, a shoreline neighborhood determination is performed. Shoreline segments with a shoreline arc length not greater than the shoreline neighborhood threshold are marked as effective affected shoreline segments, while shoreline segments with a shoreline arc length greater than the shoreline neighborhood threshold are marked as potential disturbed shoreline segments. When a shoreline segment does not intersect with either the resident disturbance buffer zone or the animal disturbance buffer zone and its shoreline arc length is greater than the shoreline neighborhood threshold, the shoreline segment is marked as an uninhabited baseline shoreline segment, and the disturbance semantics of the shoreline segment are mapped to the lake spatial unit.

8. The detection method for monitoring water bodies in plateau regions according to claim 1, characterized in that, The method for obtaining the basic score is as follows: For candidate sites of impact on residents and candidate sites of impact on animals, a basic score is obtained by weighting the effectiveness level of entry into the lake and the disturbance intensity level according to a preset weight. For candidate sites for plumes entering the lake and candidate sites for mixed transition, the effectiveness level of entering the lake will be used as the base score. For candidate control points for the lake outflow and reference candidate points for the center of the open area, the distance from the shore is used as the basic score. For unmanned baseline candidate points, the disturbance intensity level is set to 0 as a hard condition and the offshore distance is used as the base score.

9. The detection method for monitoring water bodies in plateau regions according to claim 1, characterized in that, The iterative selection method is as follows: In the candidate set, the first candidate point is selected and added to the set of selected measurement points by sorting the basic scores from high to low. After adding a candidate point to the selected test point set, calculate the Euclidean distance between the candidate point and each test point in the selected test point set that has not yet been selected in the same candidate set, and take the minimum value as the closest distance. Calculate the spatial proximity penalty value based on the closest distance, deduct the spatial proximity penalty value from the base score to obtain the current score, and then select the next candidate point to be added to the selected test point set according to the current score from high to low, until the number of candidate points added to the selected test point set reaches the test point role quota corresponding to the candidate set.

10. A detection system for monitoring water bodies in high-altitude areas, used to implement the detection method for monitoring water bodies in high-altitude areas as described in any one of claims 1-9, characterized in that, include: Data acquisition module: Acquires lake boundary data for constructing a set of lake spatial units and water system connectivity data for determining the locations of lake inlets and outlets; Spatial Unit Division Module: Based on the closed shoreline vector, the shoreline is divided into equal arc length segments to obtain shoreline segment numbers, and strip spatial units are generated accordingly. The lake surface area is divided into grids to obtain a set of lake surface grid units. The strip spatial units and the set of lake surface grid units are merged to obtain a set of lake spatial units. Semantic determination module: Calculates the distance from the shore, minimum distance into the lake, and distance out of the lake for the geometric center coordinates of the lake spatial unit, and determines the morphological semantics and water exchange semantics of the lake spatial unit accordingly; Disturbance buffer generation module: Obtains a set of spatial objects of disturbance sources and performs equidistant expansion to obtain the resident disturbance buffer region and the animal disturbance buffer region; Disturbance semantic acquisition module: Based on the intersection relationship between shoreline segments and buffer areas and combined with the coastal neighborhood, the disturbance semantics of shoreline segments are marked and mapped to lake spatial units to obtain disturbance semantics; Candidate site selection module: Based on morphological semantics, water exchange semantics and disturbance semantics, the geometric center of the lake spatial unit is included in the candidate set, and candidate sites are selected based on the maximum offshore operating distance; Iterative point selection output module: Calculate the basic score for the selected candidate points, sort the candidate points from high to low according to the basic score, select the first candidate point and record it in the selected measurement point set, calculate the spatial proximity penalty value according to the closest distance from the candidate point to the selected measurement point set, deduct it from the basic score to obtain the current score, and iteratively select the final measurement point set according to the current score.

Images