Method and device for determining appropriate threshold value of watershed vegetation recovery

Abstract

The invention relates to the technical field of watershed vegetation recovery, and discloses a watershed vegetation recovery suitable threshold determination method and device, and the method comprises the steps: obtaining a reference carbon sequestration emission reduction corresponding to a watershed reference scene scheme in a target watershed, and a carbon sequestration emission reduction caused by vegetation recovery corresponding to a watershed vegetation recovery scheme; wherein the carbon sequestration emission reduction amount caused by vegetation recovery comprises the total hydroenergy carbon emission reduction amount, the total vegetation carbon sequestration amount and the total karst carbon sequestration amount; constructing a carbon sequestration objective function based on the reference carbon sequestration emission reduction and the carbon sequestration emission reduction caused by vegetation recovery; wherein the carbon sequestration objective function takes natural constraints and vegetation restoration construction constraints as constraint conditions; and solving the carbon sequestration objective function to obtain an appropriate threshold value for vegetation recovery of the watershed. According to the method, the suitable scale of watershed vegetation construction can be rapidly and reliably calculated, scientific and technological support is provided for watershed water carbon resource simulation, evaluation and regulation and vegetation construction planning, and the method is of great significance to implementation of a dual-carbon target.

Description

Technical Field

[0001] The present invention relates to the technical field of watershed vegetation restoration, and in particular to a method and device for determining a suitable threshold value for watershed vegetation restoration. Background Art

[0002] Basin vegetation construction directly affects basin vegetation carbon sinks, and also indirectly affects karst carbon sinks and hydropower generation by changing basin runoff, thereby affecting the emission reduction benefits of clean energy.

[0003] The method for determining the appropriate threshold of basin vegetation construction analyzes the relationship between vegetation and water through model simulation, statistical analysis, and case analysis to determine the appropriate threshold of basin vegetation construction. However, it does not consider regional water production and carbon fixation at the same time, nor does it unify the impact of vegetation construction on water production, that is, the method of unifying hydropower carbon emission reduction and vegetation carbon fixation into the carbon fixation target. This leads to inaccurate calculation of the appropriate scale of basin vegetation construction, which in turn affects the simulation, evaluation and regulation of basin water and carbon resources and vegetation construction planning. Summary of the invention

[0004] In view of this, the present invention provides a method for determining a suitable threshold for watershed vegetation restoration to solve the problem of inaccurate calculation of the appropriate scale of watershed vegetation construction, which in turn affects the simulation, evaluation and regulation of water and carbon resources in the watershed and the planning of vegetation construction.

[0005] In a first aspect, the present invention provides a method for determining a suitable threshold for watershed vegetation restoration, the method comprising: Obtain the baseline carbon emission reduction corresponding to the basin baseline scenario plan in the target basin, and the carbon emission reduction caused by vegetation restoration corresponding to the basin vegetation restoration plan; the carbon emission reduction caused by vegetation restoration includes the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon sequestration and the total amount of karst carbon sequestration; The carbon sequestration objective function is constructed based on the baseline carbon sequestration emission reduction and the carbon sequestration emission reduction caused by vegetation restoration. The carbon sequestration objective function is constrained by natural constraints and vegetation restoration construction constraints. The carbon sequestration objective function was solved to obtain the appropriate threshold for watershed vegetation restoration.

[0006] The present embodiment provides a method for determining an appropriate threshold value for watershed vegetation restoration, which obtains a baseline carbon sequestration and emission reduction corresponding to a watershed baseline scenario plan in a target watershed, and a carbon sequestration and emission reduction caused by vegetation restoration corresponding to a watershed vegetation restoration plan; constructs a carbon sequestration objective function based on the baseline carbon sequestration and emission reduction and the carbon sequestration and emission reduction caused by vegetation restoration; solves the carbon sequestration objective function to obtain an appropriate threshold value for watershed vegetation restoration; from the perspective of carbon sequestration and emission reduction of vegetation construction, the two aspects of vegetation construction that directly affects watershed runoff and thus indirectly affects watershed hydropower carbon emission reduction, karst carbon sequestration, and direct changes in vegetation carbon sinks are transformed and unified into a single goal that affects carbon sequestration and emission reduction, that is, the hydropower carbon reduction effect, vegetation carbon sink, and karst carbon sink are unified into a unified objective function, while considering natural constraints and vegetation restoration construction constraints, and solving the carbon sequestration objective function, which can quickly and reliably calculate the appropriate scale of watershed vegetation construction, and provide scientific and technological support for watershed water and carbon resource simulation, evaluation and regulation, and vegetation construction planning.

[0007] In an optional implementation, obtaining a baseline carbon sequestration reduction corresponding to a baseline scenario in a target watershed and a carbon sequestration reduction caused by vegetation restoration corresponding to a watershed vegetation restoration scenario includes: Construct a water-carbon coupling model for terrestrial ecosystems in the watershed; The water-carbon coupling model of the watershed terrestrial ecosystem is used to calculate the carbon sequestration reduction caused by vegetation restoration corresponding to the watershed vegetation restoration plan; The baseline carbon sequestration reduction corresponding to the baseline scenario was calculated using the water-carbon coupling model of the watershed terrestrial ecosystem.

[0008] This embodiment provides a method for determining an appropriate threshold value for watershed vegetation restoration. The method uses a water-carbon coupling model of a watershed terrestrial ecosystem to calculate the carbon sequestration and emission reduction caused by vegetation restoration corresponding to a watershed vegetation restoration plan. From the perspective of carbon sequestration and emission reduction of vegetation construction, the two aspects of vegetation construction directly affecting watershed runoff and thus indirectly affecting watershed hydropower carbon emission reduction, karst carbon sequestration, and direct changes in vegetation carbon sinks are transformed and unified into a single goal of affecting carbon sequestration and emission reduction. The benchmark carbon sequestration and emission reduction is used to provide a reference for the carbon sequestration and emission reduction effect of watershed vegetation restoration, lays a foundation for the construction of subsequent carbon sequestration objective functions, and provides scientific and technological support for watershed water and carbon resource simulation, evaluation and regulation, and vegetation construction planning.

[0009] In an optional implementation, the water-carbon coupling model of the watershed terrestrial ecosystem is used to calculate the carbon sequestration and emission reduction caused by vegetation restoration corresponding to the watershed vegetation restoration plan, including: The water cycle of the basin vegetation restoration program was simulated using the water-carbon coupling model of the basin's terrestrial ecosystem to obtain the basin's runoff, actual evapotranspiration, groundwater runoff, surface runoff and intersoil flow; Obtain the water level drop of the river section of the target basin, and determine the total amount of hydropower carbon emission reduction caused by vegetation restoration based on the basin runoff and the water level drop of the river section of the target basin; Obtain bicarbonate concentration in groundwater runoff and determine the total amount of karst carbon sequestration caused by vegetation restoration based on groundwater runoff, surface runoff, soil flow and bicarbonate concentration; Based on water use efficiency and water carbon flux data, a statistical model including total primary productivity, ecosystem respiration, net ecosystem productivity and actual evapotranspiration of the watershed ecosystem was established; Based on actual evapotranspiration, a statistical model was used to determine the total amount of carbon sequestration caused by vegetation restoration; The carbon emission reduction caused by vegetation restoration is calculated based on the total carbon emission reduction of hydropower, the total carbon sequestration of vegetation and the total carbon sequestration of karst.

[0010] The present embodiment provides a method for determining an appropriate threshold value for watershed vegetation restoration. The method uses a water-carbon coupling model of a watershed terrestrial ecosystem to simulate the water cycle of a watershed vegetation restoration program, thereby achieving accurate simulation of the evaporation, infiltration and runoff processes of the watershed ecosystem. The total amount of hydropower carbon emission reduction and the total amount of karst carbon fixation are determined by simulating the watershed runoff, thereby reflecting the coupling process of water and carbon. Furthermore, the total amount of vegetation carbon fixation caused by vegetation restoration is calculated through a statistical model that includes the total primary productivity of the watershed ecosystem, ecosystem respiration and net ecosystem productivity and actual evapotranspiration, thereby achieving calculation of the total amount of carbon fixation caused by the vegetation itself. The water-carbon coupling model of the watershed terrestrial ecosystem is used to achieve accurate coupling simulation of water cycle elements and carbon cycle elements, thereby achieving accurate calculation of carbon fixation and emission reduction effect evaluation indicators for watershed vegetation restoration, namely, the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon fixation and the total amount of karst carbon fixation, thereby improving the accuracy of the carbon fixation and emission reduction caused by vegetation restoration.

[0011] In an optional implementation, the carbon emission reduction caused by vegetation restoration is calculated based on the total carbon emission reduction of hydropower, the total carbon sequestration of vegetation and the total carbon sequestration of karst rock; wherein the calculation formula for the carbon emission reduction caused by vegetation restoration is:

[0012] in, Indicates Carbon sequestration reduction caused by vegetation restoration corresponding to each watershed vegetation restoration plan, represents the total amount of hydropower carbon reduction caused by vegetation restoration, represents the total amount of karst carbon sequestration caused by vegetation restoration, represents the total amount of vegetation carbon sequestration caused by vegetation restoration, Represents the watershed area.

[0013] In an optional embodiment, a carbon sequestration objective function is constructed based on the baseline carbon sequestration emission reduction and the carbon sequestration emission reduction caused by vegetation restoration; wherein the expression of the carbon sequestration objective function is:

[0014]

[0015] in, represents the carbon fixation objective function, Indicates Carbon sequestration reduction caused by vegetation restoration corresponding to each watershed vegetation restoration plan, represents the baseline carbon sequestration reduction corresponding to the basin baseline scenario, Indicates Soil moisture in the watershed vegetation restoration program, represents the soil moisture threshold, Indicates the scale of vegetation restoration construction corresponding to the watershed vegetation restoration plan, Indicates the maximum scale of vegetation restoration construction.

[0016] In an optional implementation, solving the carbon sequestration objective function to obtain an appropriate threshold for watershed vegetation restoration includes: The intelligent optimization algorithm is used to solve the carbon fixation objective function and obtain the appropriate threshold for watershed vegetation restoration.

[0017] This embodiment provides a method for determining a suitable threshold value for watershed vegetation restoration, which uses an intelligent optimization algorithm to solve the carbon fixation objective function, thereby achieving accurate calculation of the suitable threshold value for watershed vegetation construction and ensuring the optimal suitable threshold value for watershed vegetation restoration under different climate change scenarios.

[0018] In a second aspect, the present invention provides a device for determining a suitable threshold value for watershed vegetation restoration, the device comprising: An acquisition module is used to obtain the baseline carbon emission reduction corresponding to the basin baseline scenario plan in the target basin, and the carbon emission reduction caused by vegetation restoration corresponding to the basin vegetation restoration plan; wherein the carbon emission reduction caused by vegetation restoration includes the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon sequestration and the total amount of karst carbon sequestration; A construction module is used to construct a carbon sequestration objective function based on the baseline carbon sequestration emission reduction and the carbon sequestration emission reduction caused by vegetation restoration; wherein the carbon sequestration objective function is constrained by natural constraints and vegetation restoration construction constraints; The solution module is used to solve the carbon fixation objective function and obtain the appropriate threshold for watershed vegetation restoration.

[0019] In a third aspect, the present invention provides a computer device comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the method for determining a suitable threshold value for watershed vegetation restoration according to the first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0020] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the method for determining a suitable threshold value for watershed vegetation restoration according to the first aspect or any corresponding embodiment thereof.

[0021] In a fifth aspect, the present invention provides a computer program product, comprising computer instructions for causing a computer to execute the method for determining a suitable threshold value for watershed vegetation restoration according to the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 is a flow chart of a method for determining a suitable threshold value for watershed vegetation restoration according to an embodiment of the present invention; Figure 2 is a flow chart of another method for determining a suitable threshold value for watershed vegetation restoration according to an embodiment of the present invention; Figure 3 is a schematic diagram of the structure of a water-carbon coupling model for a watershed terrestrial ecosystem according to an embodiment of the present invention; Figure 4 is a structural block diagram of a device for determining a suitable threshold value for watershed vegetation restoration according to an embodiment of the present invention; Figure 5 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0025] At present, the methods for determining the appropriate threshold for watershed vegetation restoration mainly include model simulation method, statistical analysis method and case analysis method.

[0026] Model simulation method: Use hydrological models (such as SWAT model, VIC model, etc.) to simulate eco-hydrology to evaluate the water supply and demand relationship after the restoration of vegetation in the basin. The above hydrological models can simulate the hydrological process under different vegetation coverage, so as to deduce the appropriate threshold for vegetation restoration. Based on remote sensing image data, combined with Geographic Information System (GIS) technology, the actual evapotranspiration of natural vegetation in the basin is estimated, and then the minimum and optimal ecological water demand calculation method for vegetation restoration is proposed.

[0027] Statistical analysis method: Through long-term observation data, statistical analysis is conducted on key indicators such as vegetation coverage, soil moisture, and rainfall in the basin to identify the key thresholds for vegetation restoration. Remote sensing monitoring methods such as the photochemical vegetation index are used, combined with ground survey data, to evaluate the vegetation restoration potential in different areas of the basin and determine the appropriate vegetation restoration threshold.

[0028] Case analysis method: Based on actual cases, by comparing the ecological effects of different vegetation restoration measures, the appropriate threshold for basin vegetation restoration is summarized and refined. This method can comprehensively consider multiple influencing factors, such as topography, climate, soil, etc.

[0029] The above methods have some shortcomings, namely the limitations of the model simulation method: some hydrological models do not take the ecological scale into consideration sufficiently, and fail to simulate in detail ecological processes such as vegetation growth, carbon and nitrogen accumulation, and their coupled interactions with hydrology. Most hydrological models can only simulate static vegetation and it is difficult to reflect the dynamic characteristics of vegetation over time and environmental changes; the shortcomings of the statistical analysis method: the statistical analysis method is highly dependent on complete data over a long period of time, but in practice such data are often difficult to obtain or missing. Simply analyzing from a single indicator such as soil water or vegetation coverage may not be able to fully reflect the suitability of vegetation restoration; the limitations of the case analysis method: there are significant differences in the natural conditions and socio-economic conditions of different basins. The results of the case analysis method may be difficult to directly apply to other basins. Although the case analysis method can comprehensively consider a variety of influencing factors, it may be difficult to achieve a comprehensive synthesis in actual operation due to difficulties in data acquisition or limited analysis methods.

[0030] In order to solve the above technical problems, an embodiment of the present invention provides a method for determining a suitable threshold value for watershed vegetation restoration. By unifying the objective function of the carbon reduction effect of hydropower, vegetation carbon sink, and karst carbon sink, and using the policy-planned vegetation restoration construction scale and the soil moisture threshold of plants under water stress as constraints, an intelligent algorithm is used to find the optimal solution to obtain the suitable threshold value for watershed vegetation construction.

[0031] The embodiment of the present invention provides a method for determining a suitable threshold value for watershed vegetation restoration. It should be noted that the method for determining a suitable threshold value for watershed vegetation restoration provided by the embodiment of the present invention may be executed by a device for determining a suitable threshold value for watershed vegetation restoration. The device for determining a suitable threshold value for watershed vegetation restoration may be implemented as part or all of an electronic device through software, hardware, or a combination of software and hardware. The electronic device may be a server or a terminal. The server in the embodiment of the present application may be a single server or a server cluster composed of multiple servers. The terminal in the embodiment of the present application may be a smart phone, a personal computer, a tablet computer, a wearable device, an intelligent robot, or other intelligent hardware devices. In the following method embodiments, the execution subject is an electronic device as an example for explanation.

[0032] According to an embodiment of the present invention, an embodiment of a method for determining a suitable threshold value for watershed vegetation restoration is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in an order different from that shown here.

[0033] In this embodiment, a method for determining a suitable threshold value for watershed vegetation restoration is provided, which can be used in the above-mentioned electronic device. Figure 1 FIG. 4 is a flow chart of a method for determining a suitable threshold value for watershed vegetation restoration according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps: Step S101, obtaining the baseline carbon sequestration and emission reduction corresponding to the basin baseline scenario plan in the target basin, and the carbon sequestration and emission reduction caused by vegetation restoration corresponding to the basin vegetation restoration plan; wherein the carbon sequestration and emission reduction caused by vegetation restoration includes the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon sequestration and the total amount of karst carbon sequestration.

[0034] Step S102, constructing a carbon sequestration objective function based on the baseline carbon sequestration emission reduction and the carbon sequestration emission reduction caused by vegetation restoration; wherein the carbon sequestration objective function is constrained by natural constraints and vegetation restoration construction constraints.

[0035] Specifically, we set future climate change scenarios and combine them with policy data such as regional vegetation construction plans to determine the policy constraint boundaries of regional vegetation construction scales (i.e., vegetation restoration construction constraints). and the soil moisture threshold for water stress on plants in the study area Constraints, set multiple vegetation restoration construction scales within the constraints ,calculate ; Among them, as soil moisture decreases, when soil moisture limits evapotranspiration, it will cause plant water stress, so a critical soil moisture threshold is defined ( ), relevant research shows that global The average value of , in arid ecosystems for In humid ecosystems for .

[0036] Furthermore, the expression of the carbon fixation objective function is: (1) (2) in, represents the carbon fixation objective function, Indicates Carbon sequestration reduction caused by vegetation restoration corresponding to each watershed vegetation restoration plan, represents the baseline carbon sequestration reduction corresponding to the basin baseline scenario, Indicates Soil moisture in the watershed vegetation restoration program, represents the soil moisture threshold, Indicates the scale of vegetation restoration construction corresponding to the watershed vegetation restoration plan, Indicates the maximum scale of vegetation restoration construction.

[0037] Step S103, solving the carbon fixation objective function to obtain an appropriate threshold for watershed vegetation restoration.

[0038] Specifically, the intelligent optimization algorithm is used to solve the carbon fixation objective function and obtain the appropriate threshold for watershed vegetation restoration.

[0039] Furthermore, the optimal solution is obtained by using intelligent optimization algorithms such as PEST (a groundwater model parameter optimization method, the core of which is to use the Marquardt-Levenberg algorithm to find the minimum value of the objective function, which is the difference function between the model calculation value and the actual observation value) and PSO (Particle Swarm Optimization). It is the appropriate value of the scale of vegetation restoration construction under the climate change scenario.

[0040] The present embodiment provides a method for determining an appropriate threshold value for watershed vegetation restoration, which obtains a baseline carbon sequestration and emission reduction corresponding to a watershed baseline scenario plan in a target watershed, and a carbon sequestration and emission reduction caused by vegetation restoration corresponding to a watershed vegetation restoration plan; constructs a carbon sequestration objective function based on the baseline carbon sequestration and emission reduction and the carbon sequestration and emission reduction caused by vegetation restoration; solves the carbon sequestration objective function to obtain an appropriate threshold value for watershed vegetation restoration; from the perspective of carbon sequestration and emission reduction of vegetation construction, the two aspects of vegetation construction that directly affects watershed runoff and thus indirectly affects watershed hydropower carbon emission reduction, karst carbon sequestration, and direct changes in vegetation carbon sinks are transformed and unified into a single goal that affects carbon sequestration and emission reduction, that is, the hydropower carbon reduction effect, vegetation carbon sink, and karst carbon sink are unified into a unified objective function, while considering natural constraints and vegetation restoration construction constraints, and solving the carbon sequestration objective function, which can quickly and reliably calculate the appropriate scale of watershed vegetation construction, and provide scientific and technological support for watershed water and carbon resource simulation, evaluation and regulation, and vegetation construction planning.

[0041] In this embodiment, a method for determining a suitable threshold value for watershed vegetation restoration is provided, which can be used in the above-mentioned electronic device. Figure 2 FIG. 4 is a flow chart of a method for determining a suitable threshold value for watershed vegetation restoration according to an embodiment of the present invention. Figure 2 As shown, the process includes the following steps: Step S201, obtain the baseline carbon sequestration and emission reduction corresponding to the basin baseline scenario plan in the target basin, and the carbon sequestration and emission reduction caused by vegetation restoration corresponding to the basin vegetation restoration plan; wherein the carbon sequestration and emission reduction caused by vegetation restoration includes the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon sequestration and the total amount of karst carbon sequestration.

[0042] Specifically, the above step S201 includes: Step S2011, constructing a water-carbon coupling model for the terrestrial ecosystem in the watershed.

[0043] Specifically, the water-carbon coupling model of the terrestrial ecosystem in the watershed can adopt models such as WaSSI (Water Supply Stress Index model), DTVGM-CASACNP (bidirectional coupling model of eco-hydrology), CHANGE (change model), RHESSys (regional hydrological ecological simulation system), CEVSA model (carbon exchange between vegetation, soil and atmosphere model, which is a biogeochemical model that simulates the carbon exchange between vegetation, soil and atmosphere based on processes such as plant photosynthesis and respiration and soil microbial activity), BEPS model (boreal ecosystem productivity simulator, a computer simulation system for simulating the carbon balance of terrestrial ecosystems), IBIS model (Input / Output Buffer Information Specification, a method for fast and accurate modeling of I / O BUFFER based on V / I curve), CASA (Carnegie-Ames-Stanford approach, a process-based remote sensing model), VIP model (vegetation interface process model) and so on.

[0044] Furthermore, if Figure 3 As shown in the figure, the meteorological, hydrological, vegetation, soil, remote sensing and other data of the basin are collected, processed and input into the water-carbon coupling model of the basin's terrestrial ecosystem, and the key processes of water and carbon cycles such as basin runoff, evapotranspiration, and total ecosystem productivity are calibrated and verified. The water-carbon coupling simulation of the basin's terrestrial ecosystem can be achieved by using WaSSI. The model integrates the potential evapotranspiration model, snowmelt model and Sacramento model, and fully considers key water and carbon elements such as terrain undulation, soil moisture, vegetation status and water partitioning, and has achieved good application results. The water-carbon coupling model of the basin's terrestrial ecosystem includes two core modules, namely the water cycle and the carbon cycle. The distributed and lumped methods are used to input rasterized remote sensing, vegetation, hydrological, soil and other data into the model, and the hydrological response unit is used as the basic calculation unit to simulate water and carbon cycle elements including surface runoff (RS), soil flow (RI), groundwater runoff (RG), evapotranspiration (ET), ecosystem gross primary productivity (GPP), ecosystem respiration (RE) and net ecosystem productivity (NEP).

[0045] Furthermore, by setting different leaf area indices and vegetation types while ensuring that other inputs of the water-carbon coupling model of the watershed terrestrial ecosystem remain unchanged, scenario simulation is carried out through the watershed terrestrial ecosystem water-carbon coupling model, and the watershed baseline scenario plan and watershed vegetation restoration plan are set.

[0046] Step S2012, using the water-carbon coupling model of the watershed terrestrial ecosystem, calculates the carbon sequestration and emission reduction caused by vegetation restoration corresponding to the watershed vegetation restoration plan.

[0047] In some optional implementations, the above step S2012 includes: Step a1, use the water-carbon coupling model of the watershed terrestrial ecosystem to simulate the water cycle of the watershed vegetation restoration plan to obtain the watershed runoff, actual evapotranspiration, groundwater runoff, surface runoff and subsoil flow.

[0048] Specifically, water cycle simulation is the calculation basis of the carbon cycle module. Water cycle simulation is mainly used to simulate the evaporation, infiltration and runoff processes of the watershed ecosystem, including the evaporation calculation process, soil moisture and infiltration calculation process, runoff calculation process, etc.; the carbon cycle module reflects the coupling process of water and carbon. This module is based on the water and carbon fluxes measured by the global flux network, and uses methods such as empirical linear regression models to construct relationships, aiming to simulate the carbon gain and loss process in the watershed.

[0049] Furthermore, if Figure 3 As shown in the figure, the Sacramento Soil Moisture Accounting model (SAC model) is used to simulate the water cycle process of the basin, which can simulate the main hydrological parameters such as actual evapotranspiration, surface runoff, soil flow and groundwater runoff; among them, considering the influence of soil moisture on evapotranspiration, The value is used as the evaporation potential input parameter of the SAC model; the actual evapotranspiration in the carbon cycle module comes from the bound water in the upper soil layer and the lower layer; at the same time, the soil parameters required for the SAC model can be estimated using soil texture data; among them, the SAC model is a deterministic model of continuous operation with lumped parameters, and is a standard soil moisture calculation model; the SAC model is based on the storage, infiltration, migration and evapotranspiration characteristics of soil moisture, and uses a series of mathematical expressions with certain physical concepts to describe the various processes of runoff formation. The state variables in the model represent a relatively independent characteristic in the hydrological cycle, and the model parameters have clear physical meanings and can be deduced based on basin characteristics, rainfall and flow data.

[0050] Furthermore, the water cycle simulation was carried out using the water-carbon coupling model of the basin's terrestrial ecosystem to simulate the basin's runoff process and calculate the basin's runoff under the basin's baseline scenario and basin's vegetation restoration scenario. and ( is 1, 2, 3...), the unit is cubic meter ( ), where the basin runoff includes groundwater runoff, surface runoff and soil flow, and the actual evapotranspiration is determined based on the bound water in the upper and lower soil layers.

[0051] Step a2, obtaining the water level difference of the river section of the target basin, and determining the total amount of hydropower carbon emission reduction caused by vegetation restoration based on the basin runoff and the water level difference of the river section of the target basin.

[0052] Specifically, the amount of electricity that can be generated is directly estimated based on the water level difference of the river section or hydropower station and the runoff of the river basin. The calculation formula for the amount of electricity that can be generated in the river basin is as follows: (3) in, It represents the theoretical reserves of water resources in the basin, that is, the amount of electricity that can be generated in the basin, in kilowatt-hours ( ), It indicates the height of the water level drop in the river section, in meters (m). Represents the watershed runoff.

[0053] Furthermore, the water-carbon coupling model of the watershed terrestrial ecosystem is used to couple the watershed runoff and hydropower to obtain the total amount of hydropower carbon emission reduction. The average emission factor of the power grid is used to calculate the change in hydropower carbon emission reduction caused by runoff change, that is, the total amount of hydropower carbon emission reduction caused by vegetation restoration. The calculation formula for the total amount of hydropower carbon emission reduction caused by vegetation restoration is as follows: (4) in, is the total amount of hydropower carbon emission reduction caused by vegetation restoration, in , 0.001 is the unit conversion factor, is the average emission factor of the power grid, in units of , .

[0054] Step a3, obtaining the bicarbonate concentration in groundwater runoff, and determining the total amount of karst carbon sequestration caused by vegetation restoration based on groundwater runoff, surface runoff, soil flow and bicarbonate concentration.

[0055] Specifically, the water-carbon coupling model of the terrestrial ecosystem in the watershed is used to obtain the groundwater runoff RGa under different vegetation restoration scales in the target watershed. Based on this, the watershed runoff modulus MRa is calculated to provide parameters for the karst carbon sink calculation. The calculation formula of the watershed runoff modulus is as follows: (5) in, is the basin runoff modulus, in units of , Indicates the drainage area in units of .

[0056] Furthermore, rock weathering is mainly the weathering and dissolution of carbonate rocks with the participation of carbonic acid. The weathering process equation is as follows: (6) (7) in, represents bicarbonate, represents calcium carbonate, represents carbon dioxide, It means water. represents calcium ion, represents calcium magnesium carbonate, Represents magnesium ion.

[0057] Furthermore, from the above formula, we can know that the carbon dioxide generated by dissolution of carbonate rocks is Only half comes from the atmosphere. , through groundwater runoff The concentration of atmospheric CO2 generated by carbonate karstification in the basin is calculated by combining the groundwater runoff data. The calculation formula is as follows: (8) in, Indicates the karst carbon sink intensity (unit: ), which is the total amount of karst carbon sequestration caused by vegetation restoration. 1 / 2 means that half of the carbon in groundwater runoff comes from the atmosphere. Indicates runoff water Mass concentration (unit: ), for The relative molecular mass is 44, for The relative molecular mass is 100, and 0.031536 is the unit conversion coefficient.

[0058] Furthermore, the surface runoff, intersoil flow and karst carbon sink were coupled using the water-carbon coupling model of the watershed terrestrial ecosystem.

[0059] Step a4, based on the water use efficiency and water carbon flux data, a statistical model including the total primary productivity, ecosystem respiration, net ecosystem productivity and actual evapotranspiration of the watershed ecosystem is established.

[0060] Specifically, Figure 3 As shown in the figure, the water cycle module in the water-carbon coupling model of the watershed terrestrial ecosystem is used to input the actual evapotranspiration obtained by water cycle simulation into the carbon cycle model to obtain the total primary productivity and ecosystem respiration of the watershed ecosystem. Then, based on the water use efficiency theory and the water-carbon flux data of the global flux network, the total primary productivity of the watershed ecosystem ( ), ecosystem respiration ( ), net ecosystem productivity ( ) and actual evapotranspiration ( ) and simulated using the water-carbon coupling model of the watershed terrestrial ecosystem (unit: mm), the terrestrial ecosystem of the basin is calculated , and , whose unit is .

[0061] Step a5, based on actual evapotranspiration, using a statistical model to determine the total amount of vegetation carbon sequestration caused by vegetation restoration.

[0062] Specifically, the total primary productivity of the watershed ecosystem The calculation formula is as follows: (9) in, represents empirical parameters derived from water-carbon flux data.

[0063] Furthermore, the ecosystem respiration of the watershed ecosystem was calculated based on the total primary productivity. The calculation formula is as follows: (10) in, and represents empirical parameters derived from water-carbon flux data.

[0064] Furthermore, the total amount of carbon sequestration by vegetation caused by vegetation restoration was calculated based on gross primary productivity and ecosystem respiration. The net ecosystem productivity (i.e., the total amount of carbon sequestration by vegetation caused by vegetation restoration) The calculation formula is as follows: (11) Step a6, calculating the carbon emission reduction caused by vegetation restoration based on the total carbon emission reduction of hydropower, the total carbon sequestration of vegetation and the total carbon sequestration of karst.

[0065] Specifically, the calculation formula for carbon sequestration and emission reduction caused by vegetation restoration is: (12) in, Indicates Carbon sequestration reduction caused by vegetation restoration corresponding to each watershed vegetation restoration plan, represents the total amount of hydropower carbon reduction caused by vegetation restoration, represents the total amount of karst carbon sequestration caused by vegetation restoration, represents the total amount of vegetation carbon sequestration caused by vegetation restoration, It represents the drainage area, and 11 / 3 is the unit conversion factor.

[0066] Step S2013, using the water-carbon coupling model of the watershed terrestrial ecosystem to calculate the baseline carbon sequestration reduction corresponding to the baseline scenario.

[0067] Specifically, when When it is 0, the benchmark carbon sequestration reduction is calculated using the above steps a1 to a6.

[0068] Step S202: construct a carbon sequestration objective function based on the baseline carbon sequestration reduction and the carbon sequestration reduction caused by vegetation restoration; wherein the carbon sequestration objective function takes natural constraints and vegetation restoration construction constraints as constraints. Figure 1 Step S102 of the illustrated embodiment will not be described in detail here.

[0069] Step S203, solve the carbon sequestration objective function to obtain the appropriate threshold for watershed vegetation restoration. Figure 1 Step S103 of the illustrated embodiment will not be described in detail here.

[0070] This embodiment provides a method for determining an appropriate threshold value for watershed vegetation restoration. The method uses a water-carbon coupling model of a watershed terrestrial ecosystem to calculate the carbon sequestration and emission reduction caused by vegetation restoration corresponding to a watershed vegetation restoration plan. From the perspective of carbon sequestration and emission reduction of vegetation construction, the two aspects of vegetation construction directly affecting watershed runoff and thus indirectly affecting watershed hydropower carbon emission reduction, karst carbon sequestration, and direct changes in vegetation carbon sinks are transformed and unified into a single goal of affecting carbon sequestration and emission reduction. The benchmark carbon sequestration and emission reduction is used to provide a reference for the carbon sequestration and emission reduction effect of watershed vegetation restoration, lays a foundation for the construction of subsequent carbon sequestration objective functions, and provides scientific and technological support for watershed water and carbon resource simulation, evaluation and regulation, and vegetation construction planning.

[0071] In this embodiment, a device for determining a suitable threshold value for watershed vegetation restoration is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware for a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0072] This embodiment provides a device for determining a suitable threshold value for watershed vegetation restoration. Figure 4 As shown, including: The acquisition module 401 is used to obtain the baseline carbon emission reduction corresponding to the watershed baseline scenario plan in the target watershed, and the carbon emission reduction caused by vegetation restoration corresponding to the watershed vegetation restoration plan; wherein the carbon emission reduction caused by vegetation restoration includes the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon sequestration and the total amount of karst carbon sequestration; A construction module 402 is used to construct a carbon sequestration objective function based on the baseline carbon sequestration emission reduction and the carbon sequestration emission reduction caused by vegetation restoration; wherein the carbon sequestration objective function takes natural constraints and vegetation restoration construction constraints as constraints; The solution module 403 is used to solve the carbon fixation objective function to obtain a suitable threshold for watershed vegetation restoration.

[0073] In some optional implementations, the acquisition module 401 includes: Construction unit, used to construct water-carbon coupling model of terrestrial ecosystem in watershed; The first calculation unit is used to calculate the carbon sequestration reduction caused by vegetation restoration corresponding to the basin vegetation restoration plan by using the water-carbon coupling model of the basin terrestrial ecosystem; The second calculation unit is used to calculate the baseline carbon sequestration reduction corresponding to the baseline scenario plan using the water-carbon coupling model of the watershed terrestrial ecosystem.

[0074] In some optional implementations, the first computing unit includes: The simulation subunit is used to simulate the water cycle of the basin vegetation restoration plan using the water-carbon coupling model of the basin terrestrial ecosystem, and obtain the basin runoff, actual evapotranspiration, groundwater runoff, surface runoff and soil flow; The first determination subunit is used to obtain the water level difference of the river section of the target basin, and determine the total amount of hydropower carbon emission reduction caused by vegetation restoration based on the basin runoff and the water level difference of the river section of the target basin; The second determination subunit is used to obtain the bicarbonate concentration in groundwater runoff, and determine the total amount of karst carbon fixation caused by vegetation restoration based on groundwater runoff, surface runoff, soil flow and bicarbonate concentration; Establish subunits for building statistical models including total primary productivity, ecosystem respiration, net ecosystem productivity and actual evapotranspiration of watershed ecosystems based on water use efficiency and water carbon flux data; The third determination subunit is used to determine the total amount of vegetation carbon sequestration caused by vegetation restoration using a statistical model based on actual evapotranspiration; The calculation subunit is used to calculate the carbon emission reduction caused by vegetation restoration based on the total carbon emission reduction of hydropower, the total carbon sequestration of vegetation and the total carbon sequestration of karst.

[0075] In some optional implementations, the calculation formula for calculating the carbon sequestration and emission reduction caused by vegetation restoration in a subunit is:

[0076] in, Indicates Carbon sequestration reduction caused by vegetation restoration corresponding to each watershed vegetation restoration plan, represents the total amount of hydropower carbon reduction caused by vegetation restoration, represents the total amount of karst carbon sequestration caused by vegetation restoration, represents the total amount of vegetation carbon sequestration caused by vegetation restoration, Represents the watershed area.

[0077] In some optional embodiments, the expression of the carbon fixation objective function in the construction module 402 is:

[0078]

[0079] in, represents the carbon fixation objective function, Indicates Carbon sequestration reduction caused by vegetation restoration corresponding to each watershed vegetation restoration plan, represents the baseline carbon sequestration reduction corresponding to the basin baseline scenario, Indicates Soil moisture in the watershed vegetation restoration program, represents the soil moisture threshold, Indicates the scale of vegetation restoration construction corresponding to the watershed vegetation restoration plan, Indicates the maximum scale of vegetation restoration construction.

[0080] In some optional implementations, the solution module 403 is specifically used to solve the carbon fixation objective function using an intelligent optimization algorithm to obtain a suitable threshold value for watershed vegetation restoration.

[0081] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0082] In this embodiment, a device for determining a suitable threshold value for watershed vegetation restoration is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above-mentioned functions.

[0083] The embodiment of the present invention also provides a computer device having the above Figure 4 A device for determining a suitable threshold value for watershed vegetation restoration is shown.

[0084] See also Figure 5 , Figure 5 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Figure 5 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 5 A processor 10 is taken as an example.

[0085] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0086] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0087] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0088] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0089] The computer device also includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30 and the output device 40 may be connected via a bus or other means. Figure 5 The example of connecting through bus is taken in the following.

[0090] The input device 30 can receive input digital or character information, and generate key signal input related to the user settings and function control of the computer device, such as a touch screen, a keypad, a mouse, a track pad, a touch pad, an indicator bar, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED) and a tactile feedback device (e.g., a vibration motor), etc. The above-mentioned display device includes but is not limited to a liquid crystal display, a light emitting diode, a display and a plasma display. In some optional embodiments, the display device may be a touch screen.

[0091] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0092] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0093] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for determining a suitable threshold for watershed vegetation restoration, characterized in that: The method comprises: Obtain the baseline carbon emission reduction corresponding to the basin baseline scenario plan in the target basin, and the carbon emission reduction caused by vegetation restoration corresponding to the basin vegetation restoration plan; wherein the carbon emission reduction caused by vegetation restoration includes the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon sequestration and the total amount of karst carbon sequestration; Constructing a carbon sequestration objective function based on the baseline carbon sequestration and emission reduction and the carbon sequestration and emission reduction caused by vegetation restoration; wherein the carbon sequestration objective function is constrained by natural constraints and vegetation restoration construction constraints; The carbon fixation objective function is solved to obtain a suitable threshold for watershed vegetation restoration.

2. The method according to claim 1, characterized in that The obtaining of the baseline carbon sequestration and emission reduction corresponding to the baseline scenario in the target watershed, and the carbon sequestration and emission reduction caused by vegetation restoration corresponding to the watershed vegetation restoration scenario, includes: Construct a water-carbon coupling model for terrestrial ecosystems in the watershed; Calculate the carbon sequestration and emission reduction caused by vegetation restoration corresponding to the vegetation restoration plan of the watershed using the water-carbon coupling model of the watershed terrestrial ecosystem; The water-carbon coupling model of the watershed terrestrial ecosystem is used to calculate the baseline carbon sequestration and emission reduction corresponding to the baseline scenario.

3. The method according to claim 2, characterized in that The method of calculating the carbon sequestration and emission reduction caused by vegetation restoration corresponding to the watershed vegetation restoration plan using the water-carbon coupling model of the watershed terrestrial ecosystem includes: Using the water-carbon coupling model of the watershed terrestrial ecosystem to simulate the water cycle of the watershed vegetation restoration plan, the watershed runoff, actual evapotranspiration, groundwater runoff, surface runoff and subsoil flow were obtained; Obtaining the water level difference of a river section in a target watershed, and determining the total amount of carbon emission reduction of hydropower caused by the vegetation restoration based on the watershed runoff and the water level difference of a river section in the target watershed; Obtaining the bicarbonate concentration in the groundwater runoff, and determining the total amount of karst carbon fixation caused by the vegetation restoration based on the groundwater runoff, surface runoff, soil flow and the bicarbonate concentration; Based on water use efficiency and water carbon flux data, a statistical model including total primary productivity, ecosystem respiration, net ecosystem productivity and actual evapotranspiration of the watershed ecosystem was established; Based on the actual evapotranspiration, determining the total amount of vegetation carbon sequestration caused by the vegetation restoration using the statistical model; The carbon emission reduction amount caused by vegetation restoration is calculated based on the total hydropower carbon emission reduction amount, the total vegetation carbon fixation amount and the total karst carbon fixation amount.

4. The method according to claim 3, characterized in that The carbon emission reduction caused by vegetation restoration is calculated based on the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon fixation and the total amount of karst carbon fixation; wherein the calculation formula for the carbon emission reduction caused by vegetation restoration is: in, Indicates Carbon sequestration reduction caused by vegetation restoration corresponding to each watershed vegetation restoration plan, represents the total amount of hydropower carbon reduction caused by vegetation restoration, represents the total amount of karst carbon sequestration caused by vegetation restoration, represents the total amount of vegetation carbon sequestration caused by vegetation restoration, Represents the watershed area.

5. The method according to claim 1, characterized in that The carbon sequestration objective function is constructed based on the benchmark carbon sequestration and emission reduction and the carbon sequestration and emission reduction caused by vegetation restoration; wherein the expression of the carbon sequestration objective function is: in, represents the carbon fixation objective function, Indicates Carbon sequestration reduction caused by vegetation restoration corresponding to each watershed vegetation restoration plan, represents the baseline carbon sequestration reduction corresponding to the basin baseline scenario, Indicates Soil moisture in the watershed vegetation restoration program, represents the soil moisture threshold, Indicates the scale of vegetation restoration construction corresponding to the watershed vegetation restoration plan, Indicates the maximum scale of vegetation restoration construction.

6. The method according to claim 1, characterized in that Solving the carbon fixation objective function to obtain a suitable threshold for watershed vegetation restoration includes: The carbon fixation objective function is solved using an intelligent optimization algorithm to obtain a suitable threshold for vegetation restoration in the watershed.

7. A device for determining a suitable threshold value for watershed vegetation restoration, characterized in that: The device comprises: An acquisition module is used to obtain the baseline carbon emission reduction corresponding to the basin baseline scenario plan in the target basin, and the carbon emission reduction caused by vegetation restoration corresponding to the basin vegetation restoration plan; wherein the carbon emission reduction caused by vegetation restoration includes the total amount of hydropower carbon emission reduction, the total amount of vegetation carbon sequestration and the total amount of karst carbon sequestration; A construction module is used to construct a carbon sequestration objective function based on the baseline carbon sequestration and emission reduction amount and the carbon sequestration and emission reduction amount caused by vegetation restoration; wherein the carbon sequestration objective function takes natural constraints and vegetation restoration construction constraints as constraints; The solution module is used to solve the carbon fixation objective function to obtain a suitable threshold for watershed vegetation restoration.

8. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the method for determining a suitable threshold value for watershed vegetation restoration according to any one of claims 1 to 6 by executing the computer instructions.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method for determining a suitable threshold value for watershed vegetation restoration according to any one of claims 1 to 6.

10. A computer program product, characterized in that It comprises computer instructions, and the computer instructions are used to make a computer execute the method for determining a suitable threshold value for watershed vegetation restoration according to any one of claims 1 to 6.

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