Forest stand structure optimization method, equipment and medium

Abstract

The invention discloses a forest stand structure optimization method and device and a medium, and relates to the field of forest management in forestry scientific research, and the method comprises the steps: determining a forest tree structure unit of each structure parameter of each object tree according to the forest stand survey data of a to-be-optimized forest stand structure, determining structure parameters according to object trees and adjacent trees in the forest tree structure units; determining a forest structure unit evaluation index according to each structure parameter so as to determine a to-be-cut object tree; and determining a forest stand structure evaluation index of the to-be-optimized forest stand overall structure according to the structure parameter corresponding to each object tree so as to determine the cutting strength. According to the method, the forest stand structure can be guided and optimized more accurately and scientifically.

Description

Technical Field

[0001] The present application relates to the field of forest management in forestry science research, and in particular to a forest stand structure optimization method, equipment and medium. Background Art

[0002] Forest structure determines forest function. Quantitative description of forest structure is the basis for transforming forest phases, optimizing forest stand structure, and improving forest ecological service functions. At present, there are many indicators to describe forest stand structure. From the research scale, they can be divided into single tree indicators, diameter indexes, and forest stand indicators. From whether the relative position of trees is considered, they can be divided into non-spatial structure indicators and spatial structure indicators. However, these indicators are descriptions of certain aspects of forest structure, and cannot fully reflect the characteristics of forest stand structure, nor can they scientifically guide the optimization of forest stand structure. Summary of the invention

[0003] The purpose of this application is to provide a forest stand structure optimization method, equipment and medium, which can more accurately and scientifically guide the optimization of forest stand structure.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] In a first aspect, the present application provides a forest stand structure optimization method, comprising:

[0006] Determine a forest structure unit for each structural parameter of each target tree according to forest stand survey data of the forest stand structure to be optimized, and determine each structural parameter corresponding to the target tree according to the target tree and adjacent trees in the forest structure unit; the target tree is any tree in the forest stand structure to be optimized; the structural parameters include a breast diameter size diversity parameter, an angle scale parameter, a mixed degree parameter and a density parameter; one target tree corresponds to four structural parameters, and each structural parameter corresponds to a forest structure unit; each of the forest structure units includes the target tree and adjacent trees; the adjacent trees corresponding to one target tree in different forest structure units are different; the adjacent trees refer to trees adjacent to the target tree;

[0007] Determine the forest structure unit evaluation index of each target tree according to the structural parameters corresponding to each target tree;

[0008] Determine the forest stand structure evaluation index of the overall forest stand structure to be optimized according to the structural parameters corresponding to each of the target trees;

[0009] Determining the target trees to be felled in the forest stand structure to be optimized according to the forest structure unit evaluation index;

[0010] The felling intensity of the forest stand structure to be optimized is determined according to the forest stand structure evaluation index.

[0011] In a second aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the forest stand structure optimization method.

[0012] In a third aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which implements the forest stand structure optimization method when executed by a processor.

[0013] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0014] The present application provides a forest stand structure optimization method, equipment and medium, which determines the forest structure unit corresponding to each structural parameter, selects different adjacent trees to form the forest structure unit for each structural parameter, and selects different adjacent trees to calculate each structural parameter. When calculating different structural parameters, a variable number of adjacent trees are used. Compared with using fixed adjacent trees to calculate each structural parameter, it can more accurately characterize the differences in individual trees and their microenvironments in the forest stand space from different angles, so as to more accurately evaluate the growth environment of each tree, so as to more accurately and scientifically guide the optimization of the forest stand structure. In addition, each structural parameter is integrated into a comprehensive evaluation index (i.e., a forest structure unit evaluation index), so as to more accurately evaluate whether the microenvironment in which each tree is located is conducive to the growth of the tree, so as to more accurately and scientifically guide the optimization of the forest stand structure. In addition, the forest stand structure evaluation index is further calculated based on each structural parameter, and the overall structural condition of the forest stand is more accurately evaluated to determine the optimal felling intensity, so as to more accurately and scientifically guide the optimization of the forest stand structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 This is an application environment diagram of a forest stand structure optimization method in an embodiment of the present application;

[0017] Figure 2 A schematic diagram of a flow chart of a forest stand structure optimization method provided in one embodiment of the present application;

[0018] Figure 3 A schematic diagram of a technical route of a forest stand structure optimization method provided in one embodiment of the present application;

[0019] Figure 4 A schematic diagram of a forest structure unit corresponding to a breast diameter diversity parameter provided in an embodiment of the present application;

[0020] Figure 5 A schematic diagram of a forest structure unit corresponding to the angular scale parameters provided in an embodiment of the present application;

[0021] Figure 6 A schematic diagram of a forest structure unit corresponding to a mixed degree parameter provided in an embodiment of the present application;

[0022] Figure 7 A schematic diagram of a forest structure unit corresponding to a density parameter provided in an embodiment of the present application;

[0023] Figure 8 A schematic diagram of the stand structure evaluation index corresponding to the simulated felled number provided in an embodiment of the present application;

[0024] Fig. 9 A schematic diagram of the structure of a computer device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0027] The forest stand structure optimization method provided in the embodiment of the present application can be applied to Figure 1In the application environment shown. Among them, the terminal 102 communicates with the server 104 through the network. The data storage system can store the data that the server 104 needs to process. The data storage system can be set up separately, or it can be integrated on the server 104, or it can be placed on the cloud or other servers. The terminal 102 can send the forest stand survey data of the trees in the forest stand structure to be optimized to the server 104, and the server 104 receives the forest stand survey data of the trees in the forest stand structure to be optimized. The server 104 determines the forest structure unit of each structural parameter of each object tree according to the forest stand survey data of the forest stand structure to be optimized, and determines each structural parameter corresponding to the object tree according to the object tree and the adjacent trees in the forest structure unit, and determines the forest structure unit evaluation index of each object tree according to the structural parameters corresponding to each object tree; determines the forest structure evaluation index of the overall structure of the forest stand to be optimized according to the structural parameters corresponding to each object tree; determines the object tree to be felled in the forest stand structure to be optimized according to the forest structure unit evaluation index; determines the felling intensity of the forest stand structure to be optimized according to the forest structure evaluation index. The server 104 can feed back the obtained target trees to be felled and felling intensity to the terminal 102. In addition, in some embodiments, the forest stand structure optimization method can also be implemented by the server 104 or the terminal 102 alone, such as the terminal 102 can directly perform forest stand structure optimization processing on the forest stand survey data of the trees in the forest stand structure to be optimized, or the server 104 can obtain the forest stand survey data of the trees in the forest stand structure to be optimized from the data storage system and perform forest stand structure optimization processing.

[0028] The terminal 102 may be, but is not limited to, various desktop computers, laptop computers, smart phones, tablet computers, IoT devices, and portable wearable devices. The IoT devices may be smart speakers, smart TVs, smart air conditioners, smart vehicle-mounted devices, etc. The portable wearable devices may be smart watches, smart bracelets, head-mounted devices, etc. The server 104 may be implemented as an independent server or a server cluster consisting of multiple servers, or may be a cloud server.

[0029] In an exemplary embodiment, Figure 2 and Figure 3 As shown, a forest stand structure optimization method is provided. The method is executed by a computer device, and can be executed by a computer device such as a terminal or a server alone, or by a terminal and a server together. In the embodiment of the present application, the method is applied to Figure 1 The server 104 in FIG. 1 is used as an example for explanation. The forest stand structure optimization method includes the following steps 201 to 205.

[0030] Step 201, determine the tree structure unit of each structural parameter of each target tree according to the forest stand survey data of the forest stand structure to be optimized, and determine each structural parameter corresponding to the target tree according to the target tree and adjacent trees in the tree structure unit; the target tree is any tree in the forest stand structure to be optimized; the structural parameters include a breast diameter size diversity parameter, an angle scale parameter, a mixed degree parameter and a density parameter; one target tree corresponds to four structural parameters, and each structural parameter corresponds to a tree structure unit; each of the tree structure units includes the target tree and adjacent trees; the adjacent trees corresponding to one target tree in different tree structure units are different; the adjacent trees refer to trees adjacent to the target tree.

[0031] Among them, the forest stand survey data include the tree's breast diameter, tree height, crown width and relative coordinates, etc. These data can be used to determine the adjacent trees in different structural units.

[0032] Step 202: determining a forest structural unit evaluation index of each target tree according to the structural parameters corresponding to each target tree.

[0033] Step 203: determining a forest stand structure evaluation index of the overall forest stand structure to be optimized according to the structural parameters corresponding to each of the target trees.

[0034] Step 204: determining the target trees to be felled in the forest stand structure to be optimized according to the forest structure unit evaluation index.

[0035] Step 205: determining the felling intensity of the forest stand structure to be optimized according to the forest stand structure evaluation index.

[0036] Implement the above-mentioned steps 201 to 205, based on the forest stand survey data, according to the ecological significance of the structural parameters, divide the forest structure units, use a variable number of adjacent trees to construct the structural parameters, thereby constructing the forest structure unit index to determine the felled trees, and construct the forest structure evaluation index to determine the optimal felling intensity, and guide the application of forest structure optimization management. Specifically, based on the forest attributes and their spatial relationships in the forest stand, the differences between individual trees and their microenvironment are quantified, and the forest structure unit evaluation index is constructed to determine the felled trees, and the forest structure evaluation index is constructed to determine the felling intensity. Computer technology is used to iteratively simulate the felling of the trees with the smallest value of the forest structure unit evaluation index F. Under the condition of felling threshold restrictions (felling volume or number of trees not exceeding 15%), the felling volume corresponding to the maximum value of the forest structure evaluation index TF is the optimal felling intensity. The method of the present invention is scientific and effective, fully considering the importance of individual trees in the forest stand, accurately selecting felled trees and felling intensity in the management of ecological public welfare forests, and the simulation results meet the needs of accurate improvement of public welfare forest quality and structural optimization.

[0037] In another exemplary embodiment of the present application, forest refers to individual trees in a forest stand. In addition to being regulated by large-scale environmental factors such as climate and geography, the growth of forests is also mainly affected by themselves and their microenvironment. The use of structural parameters to quantitatively describe the differences between forests and their microenvironment is the key to evaluating the current and future growth potential of forests, and forest structural units are the prerequisite for calculating structural parameters. At present, forest structural units are generally divided according to the nearest number of adjacent trees, such as the nearest 4, 6 or 8 trees, or adjacent trees are determined through Voronoi diagrams or weighted Voronoi diagrams to construct forest structural units, and then structural parameters such as angular scale are used to describe forest structural units.

[0038] Adjacent trees refer to neighboring trees that are close to the target tree, but there is no unified standard for the selection of adjacent trees. Considering the ecological significance of structural parameters, there is a positive or negative relationship between the parameters. Using a fixed number of adjacent trees to construct structural parameters cannot fully characterize the differences between trees and their microenvironments. Therefore, it is more reasonable to use a variable number of adjacent trees to determine the forest structural unit and thus construct structural parameters.

[0039] For the four structural parameters of breast diameter size diversity parameter, angle scale parameter, intermixing degree parameter and density parameter, each structural parameter corresponds to a forest structural unit.

[0040] The DBH size diversity parameter U is used to describe the differentiation of tree sizes, and its ecological significance indicates the degree of niche differentiation within a forest structural unit. The DBH size diversity parameter U is determined by using the nearest neighbor trees based on multiple quadrants (e.g., four quadrants), such as Figure 4 Therefore, in step 201, determining the forest structure unit of the DBH size diversity parameter of each target tree, and determining the DBH size diversity parameter according to the target tree and adjacent trees in the forest structure unit specifically includes:

[0041] (a1) For each of the target trees, a plurality of quadrants are divided with the target tree as the origin.

[0042] (a2) determining the tree closest to the target tree in each quadrant, and recording it as the first adjacent tree. The first adjacent tree and the target tree constitute a tree structural unit corresponding to the DBH size diversity parameter.

[0043] (a3) determining the DBH size diversity parameter of the target tree according to the DBH of the first adjacent tree and the DBH of the target tree in each quadrant.

[0044] As an optional implementation, the formula for the DBH size diversity parameter of the object tree i is:

[0045]

[0046] In the formula, i is the target tree, j is the nearest neighboring tree to the target tree in each quadrant, that is, the first neighboring tree, d i is the breast diameter of the target tree, d j is the breast diameter of adjacent trees, m is the number of divided quadrants, and when divided into four quadrants, m is 4.

[0047] In another exemplary embodiment of the present application, the angular scale parameter W is used to describe the tree distribution pattern, and its ecological significance represents the horizontal distribution pattern of trees in a forest structural unit. The angular scale parameter W is determined by using several nearest neighboring trees, such as Figure 5 Therefore, in step 201, determining the forest structure unit of the angle scale parameter of each target tree, and determining the angle scale parameter according to the target tree and adjacent trees in the forest structure unit specifically includes:

[0048] (b1) For each target tree, a preset number of trees closest to the target tree are determined and recorded as second adjacent trees. The second adjacent trees and the target tree form a tree structure unit corresponding to the angle scale parameter.

[0049] (b2) determining an angle between the target tree and each of the second adjacent trees.

[0050] (b3) determining the angle dimension parameter of the target wood according to the angle between the target wood and each of the second adjacent woods.

[0051] As an optional implementation, the formula for the angular scale parameter W of the object tree i is:

[0052]

[0053] In the formula, i is the target tree, j is the adjacent tree, i.e. the second adjacent tree, g is the number of adjacent trees, and Z ij It is defined as when the angle a formed by the object wood i and the adjacent wood j is less than the standard angle a 0 (e.g. 72°), the value is 1, otherwise it is 0. When g = 4, W i The possible values ​​are 0, 0.25, 0.5, 0.75 and 1.

[0054] In another exemplary embodiment of the present application, a mixed degree parameter M is used to describe the degree of tree species mixing, and its ecological significance indicates the richness of tree species in a forest structure unit. Adjacent trees whose crown width overlaps with the crown width of the target tree are selected as adjacent trees, and the forest structure unit with the mixed degree parameter M is determined, such as Figure 6 Therefore, in step 201, determining the forest structure unit of the intermixing degree parameter of each target tree, and determining the intermixing degree parameter according to the target tree and adjacent trees in the forest structure unit specifically includes:

[0055] (c1) For each target tree, determine the tree whose tree crown width intersects with the crown width of the target tree, and record it as the third adjacent tree. The third adjacent tree and the target tree constitute a tree structural unit corresponding to the intermixing degree parameter.

[0056] (c2) determining the intermixing degree parameter of the target tree according to the number of the third adjacent trees and the tree species types of the third adjacent trees and the target tree.

[0057] As an optional implementation, the formula for the mixed degree parameter M of object tree i is:

[0058]

[0059] In the formula, i is the target tree, j is the adjacent tree, that is, the third adjacent tree, n is the number of adjacent trees, V ij It is defined as 1 when the jth adjacent tree is of the same species as the object tree i, and 0 otherwise; that is, M i The value range is 0 to 1.

[0060] In another exemplary embodiment of the present application, a density parameter C is used to describe the degree of tree aggregation, and its ecological significance indicates whether the trees in the forest structure unit are sparse. The forest structure unit with density C is determined by using the nearest neighbor tree based on the four quadrants, such as Figure 7 Therefore, in step 201, determining the forest structure unit of the density parameter of each target tree, and determining the density parameter according to the target tree and adjacent trees in the forest structure unit, specifically includes:

[0061] (d1) For each of the target trees, a plurality of quadrants are divided with the target tree as the origin.

[0062] (d2) determining the tree closest to the target tree in each quadrant and recording it as the fourth adjacent tree. The fourth adjacent tree and the target tree constitute a tree structure unit corresponding to the density parameter.

[0063] (d3) Determining the density parameter of the target tree according to the crown width of the fourth adjacent tree and the crown width of the target tree in each quadrant.

[0064] As an optional implementation, the density parameter C of the object tree i is formulated as follows:

[0065]

[0066] In the formula, i is the target tree, j is the nearest neighboring tree to the target tree in each quadrant, that is, the fourth neighboring tree, CW i is the crown width of the object tree i, CW j is the crown width of the adjacent tree j, L ijis the distance between the target tree and the adjacent tree. e is the number of quadrants. When divided into four quadrants, e is 4.

[0067] In another exemplary embodiment of the present application, each structural parameter characterizes the differences between individual trees and their microenvironments in the forest stand space from different angles, and plays an important indicative role in evaluating the growth environment of trees. According to the ecological significance of the structural parameters, the larger the values ​​of the breast diameter diversity parameter U and the degree of interbreeding M, the better, the optimal value of the angular scale W is 0.5, and the smaller the density C, the better. However, the structural parameters influence each other, and the parameter values ​​cannot reach the optimal value at the same time, and the quality of the forest structure unit cannot be evaluated by a single structural parameter. Therefore, multiple structural parameters are integrated into a comprehensive evaluation index through multiplication and division to quantify the quality of the forest structure unit, so as to evaluate whether the microenvironment in which the trees are located is conducive to the growth of the trees according to the numerical value of the evaluation index. Therefore, in step 202, the expression of the evaluation index of the forest structure unit is:

[0068]

[0069] In the formula, F i is the evaluation index of the forest structure unit of the object tree i. Its ecological significance indicates the overall quality of the spatial structure of the object tree and its microenvironment. The larger the value, the better the spatial structure of the forest and its microenvironment, and the closer it is to the ideal spatial structure unit state. i , U i , W i , C i They are the mixed degree parameter, breast diameter size diversity parameter, mixed angle parameter and density parameter of the object tree i respectively.

[0070] The organic combination of various stand structure indicators into a stand structure evaluation index with ecological significance and quantitative comparison will scientifically guide the optimization of stand structure and the formulation and implementation of forest management plans. Based on the structural unit evaluation index value of each tree in the stand, trees with lower values ​​have a poor growth environment, while trees with higher values ​​have growth advantages. By felling trees with lower values ​​of the structural unit index and improving the stand spatial structure, it will help promote the near-natural evolution of ecological public welfare forests and improve ecological service functions.

[0071] In another exemplary embodiment of the present application, each tree in the forest stand is not only the target tree of a certain forest structure unit, but also the adjacent tree of other forest structure units. Therefore, the evaluation index of the forest structure unit is not isolated, and there may be a positive or negative relationship between the indicators. Therefore, it is necessary to evaluate the overall structural condition of the forest stand in order to scientifically guide the intensity of tending and felling, and achieve the maximum forest stand structure optimization with minimal human intervention to enhance the forest ecological service function. The forest structure unit indicator value and its standard deviation can describe the forest stand structure and its dynamics after forest management. Therefore, the multiplication and division method is used to construct the forest stand structure evaluation index TF to evaluate the overall structural condition of the forest stand. Its ecological significance represents the overall quality of the forest stand structure. The larger the value, the better the forest stand structure and the closer it is to the ideal forest stand spatial structure state. Therefore, in step 203, the forest stand structure evaluation index of the overall structure of the forest stand to be optimized is determined according to the structural parameters, specifically including:

[0072] (1) Determine the mean and standard deviation of each structural parameter corresponding to each of the object trees.

[0073] (2) Determine the forest stand structure evaluation index based on the mean and standard deviation of each structural parameter.

[0074] As an optional implementation, the expression of the stand structure evaluation index is:

[0075]

[0076] In the formula, TF is the forest stand structure evaluation index; They are the means of the mixed degree parameter, DBH size diversity parameter, mixed angle parameter and density parameter respectively; They are the standard deviations of the mixed degree parameter, breast diameter size diversity parameter, mixed angle parameter and density parameter respectively.

[0077] The present application also provides an application scenario, which applies the above-mentioned forest stand structure optimization method. Specifically: The forest stand structure optimization method provided in this embodiment can be applied in the scenario of forest management plan formulation and implementation. The scenario includes a forest structure optimization simulation link, a forest management plan formulation link, and a forest management plan implementation link. The forest stand structure optimization method provided in this embodiment belongs to the forest structure optimization simulation link to obtain the optimization simulation results, and then formulates a forest management plan based on the simulation results to implement the plan.

[0078] Masson pine is one of the artificial afforestation tree species, but the artificially planted forests generally have simple structures and low quality. At the same time, with the change of ecological protection policies, some Masson pine plantations have been converted into ecological public welfare forests, and the problem of weak ecological service functions is more serious. It is urgent to optimize the structure of Masson pine ecological public welfare forests to enhance their ecological service functions. This embodiment can use Masson pine ecological public welfare forests as the forest stand structure to be optimized to illustrate the optimization method of the present invention.

[0079] (1) Data collection: Based on three public welfare Masson pine forest sample plots in the general control area of ​​a conservation center, all tree species with a breast diameter greater than 5 cm in the sample plots were investigated, and their relative coordinates, breast diameter, tree height, crown width and other information were recorded. The forest stand information is shown in Table 1.

[0080] Table 1 Forest stand information

[0081]

[0082] (2) Calculation of initial structural parameters of forest structural units

[0083] According to the forest stand survey data, the initial structural parameters of the tree structure unit of the Masson pine public welfare forest were calculated, and the numerical range is shown in Table 2. The mean value of the size diversity parameter U of the three Masson pine ecological public welfare forest plots is between 0.48 and 0.51, indicating that most of the trees in the plots are in a moderate state and the heterogeneity is poor; the mean value of the angular scale W is between 0.32 and 0.45, indicating that most of the trees in the plots are evenly distributed and the competition is fierce; the mean value of the mixed degree M is between 0.15 and 0.38, indicating that there are fewer mixed tree species and the degree of mixedness is not high; and the mean value of the density C is between 0.97 and 0.99, indicating that the degree of aggregation of trees in the forest stand is high and the density is too high. The mean value of the forest structure unit evaluation index F is between 0.39 and 0.46, while the mean value of the forest structure evaluation index TF is between 0.13 and 0.18, which is relatively low, indicating that the overall structure of the forest stand is relatively simple and the ecological service function is weak. It is urgent to carry out forest structure optimization management activities to improve the forest stand structure and enhance the ecological function of the ecological public welfare forest.

[0084] Table 2 Parameters of forest structural units (mean ± standard deviation)

[0085]

[0086] (3) Simulated felling

[0087] Under the condition that the intensity of tending and felling (stock volume or number of trees) of ecological public welfare forest is limited to no more than 15%, the forest trees with the lowest value of forest structure unit evaluation index F (target trees) are simulated to be gradually felled. The forest stand structure evaluation index TF changes as follows: Figure 8As shown. Among the three Masson pine ecological public welfare forest plots, plot 1 has 115 trees, 5 tree species, and 21 trees can be harvested. As the number of harvested trees increases, the forest structure evaluation index TF value increases. When the 21st tree is harvested, TF reaches the relative maximum value (0.14), an increase of 7.69% over the initial value, that is, the optimal harvesting intensity is 21 trees. Plot 2 has 98 trees, 4 tree species, and 17 trees can be harvested. As the number of harvested trees increases, the forest structure evaluation index TF growth trend fluctuates greatly, reaching the maximum (0.15) when the 16th tree is harvested, an increase of 15.38% over the initial value, that is, the optimal harvesting intensity is 16 trees. There are 137 trees in plot 3, with 6 tree species, and 25 trees can be harvested. As the number of harvested trees increases, the stand structure evaluation index TF shows an increasing trend and reaches the maximum (0.2) when the 23rd tree is harvested, an increase of 35.29% over the initial value, that is, the optimal harvesting intensity is 23 trees.

[0088] (4) Parameters of forest structural units for optimal felling intensity

[0089] The parameters of the forest structure unit after optimizing the stand structure according to the optimal felling intensity are shown in Table 3. The mean value of the size diversity parameter U of the three Masson pine ecological public welfare forests is between 0.37 and 0.9, and the number of trees with size advantages is large, that is, most of the felled trees are at a growth disadvantage, which is 22.45% to 23.53% optimized compared with the initial stand; the mean value of the angular scale W is between 0.38 and 0.49, which is 8.89% to 18.75% higher than the initial stand; the mean value of the mixed degree M is between 0.21 and 0.52, which is 36.84% to 43.75% higher than the initial stand; the mean value of the density C is between 0.92 and 0.97, which is lower than the initial stand density, but the trees are still relatively concentrated; and the mean value of the forest structure unit evaluation index F is between 0.51 and 0.53, which is 19.57% to 30.77% higher than the initial stand. The stand structure evaluation index TF values ​​of the three sample plots were 0.14-0.2, which were 15.38%-17.65% higher than the initial stands.

[0090] Table 3 Parameters of forest structural units (mean ± standard deviation)

[0091]

[0092]

[0093] According to the structure optimization method of Masson pine ecological public welfare forest proposed in the present invention, a forest structure unit evaluation index F is constructed based on the breast diameter size diversity parameter U, angular scale W, mixed degree M and density C, which accurately quantifies the importance of trees in the forest stand. By felling trees of low importance, the forest stand structure characteristics are optimized, thereby achieving the purpose of maximizing the forest ecological service function with minimal human intervention.

[0094] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Fig. 9 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store forest stand structure optimization result data. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a forest stand structure optimization method is implemented.

[0095] Those skilled in the art will understand that Fig. 9 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0096] In an exemplary embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0097] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0098] In an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0099] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0100] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0101] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0102] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A forest stand structure optimization method, characterized in that: include: Determine a forest structure unit for each structural parameter of each target tree according to forest stand survey data of the forest stand structure to be optimized, and determine each structural parameter corresponding to the target tree according to the target tree and adjacent trees in the forest structure unit; the target tree is any tree in the forest stand structure to be optimized; the structural parameters include a breast diameter size diversity parameter, an angle scale parameter, a mixed degree parameter and a density parameter; one target tree corresponds to four structural parameters, and each structural parameter corresponds to a forest structure unit; each of the forest structure units includes the target tree and adjacent trees; the adjacent trees corresponding to one target tree in different forest structure units are different; the adjacent trees refer to trees adjacent to the target tree; Determine the forest structure unit evaluation index of each target tree according to the structural parameters corresponding to each target tree; Determine the forest stand structure evaluation index of the overall forest stand structure to be optimized according to the structural parameters corresponding to each of the target trees; Determining the target trees to be felled in the forest stand structure to be optimized according to the forest structure unit evaluation index; The felling intensity of the forest stand structure to be optimized is determined according to the forest stand structure evaluation index.

2. The forest stand structure optimization method according to claim 1, characterized in that: Determining a forest structural unit of a breast diameter diversity parameter of each target tree, and determining the breast diameter diversity parameter according to the target tree and adjacent trees in the forest structural unit, specifically includes: For each of the target trees, a plurality of quadrants are divided with the target tree as the origin; Determine the tree closest to the target tree in each quadrant, record it as the first adjacent tree; the first adjacent tree and the target tree constitute a tree structure unit corresponding to the DBH size diversity parameter; The diameter at breast height size diversity parameter of the target tree is determined according to the diameter at breast height of the first adjacent tree and the diameter at breast height of the target tree in each quadrant.

3. The forest stand structure optimization method according to claim 1, characterized in that: Determining a forest structural unit of an angle scale parameter of each target tree, and determining the angle scale parameter according to the target tree and adjacent trees in the forest structural unit, specifically includes: For each of the target trees, a preset number of trees closest to the target tree are determined and recorded as second adjacent trees; the second adjacent trees and the target tree form a tree structure unit corresponding to the angle scale parameter; determining an angle between the target wood and each of the second adjacent woods; The angle dimension parameter of the target wood is determined according to the included angle between the target wood and each of the second adjacent woods.

4. The forest stand structure optimization method according to claim 1, characterized in that: Determining a forest structural unit of a mixed degree parameter of each target tree, and determining the mixed degree parameter according to the target tree and adjacent trees in the forest structural unit, specifically includes: For each of the target trees, determine the trees whose tree crown width intersects with the crown width of the target tree, and record them as the third adjacent trees; the third adjacent trees and the target tree constitute a tree structure unit corresponding to the intermixing degree parameter; The intermixing degree parameter of the target tree is determined according to the number of the third adjacent trees and the tree species types of the third adjacent trees and the target tree.

5. The forest stand structure optimization method according to claim 1, characterized in that: Determining a forest structure unit of a density parameter of each target tree, and determining the density parameter according to the target tree and adjacent trees in the forest structure unit, specifically includes: For each of the target trees, a plurality of quadrants are divided with the target tree as the origin; Determine the tree closest to the target tree in each quadrant, record it as the fourth adjacent tree; the fourth adjacent tree and the target tree constitute a tree structure unit corresponding to the density parameter; The density parameter of the target tree is determined according to the crown width of the fourth adjacent tree in each quadrant and the crown width of the target tree.

6. The forest stand structure optimization method according to any one of claims 1 to 5, characterized in that: The expression of the evaluation index of the forest structure unit is: In the formula, F i is the evaluation index of the forest structure unit of the object tree i; M i , U i , W i , C i They are the mixed degree parameter, breast diameter size diversity parameter, mixed angle parameter and density parameter of the object tree i respectively.

7. The forest stand structure optimization method according to claim 1, characterized in that: Determining the forest stand structure evaluation index of the overall forest stand structure to be optimized according to the structural parameters corresponding to each of the target trees specifically includes: Determine the mean and standard deviation of each of the structural parameters corresponding to each of the object trees; The forest stand structure evaluation index is determined according to the mean and standard deviation of each structural parameter.

8. The forest stand structure optimization method according to claim 7, characterized in that: The expression of the stand structure evaluation index is: In the formula, TF is the forest stand structure evaluation index; They are the means of the mixed degree parameter, DBH size diversity parameter, mixed angle parameter and density parameter respectively; They are the standard deviations of the mixed degree parameter, breast diameter size diversity parameter, mixed angle parameter and density parameter respectively.

9. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the forest stand structure optimization method according to any one of claims 1 to 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the forest stand structure optimization method according to any one of claims 1 to 8 is implemented.

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