Assessment method of regional available water resources affected by vegetation evapotranspiration water vapor cycle

Abstract

The present invention belongs to the technical field of surface evapotranspiration assessment, and discloses an assessment method for the influence of vegetation evapotranspiration water vapor cycle on regional available water resources. First, based on the surface water loss data of the area to be studied, the vegetation evapotranspiration ratio is calculated, and the precipitation recovery caused by the surface water loss is determined. Subsequently, the precipitation recovery amount and the vegetation evapotranspiration ratio are combined to obtain the precipitation data of the vegetation evapotranspiration water vapor contribution to the precipitation in the region. By analyzing the regional precipitation data, the original available water resources data and the precipitation data under the condition of no vegetation evapotranspiration water vapor cycle are determined, and then the first available water resources data are obtained. Finally, by comparing the original and first available water resources data, the contribution rate of the vegetation evaporation water vapor cycle to the regional available water resources is calculated, and the quantitative assessment of the influence of the vegetation evapotranspiration water vapor cycle on the available water resources is realized, which fills the gap in the current research on the quantification of the efficiency of the vegetation evapotranspiration water vapor cycle.

Description

Technical Field

[0001] The invention discloses an evaluation method for the influence of vegetation evapotranspiration water vapor cycle on the available water resources in a region, and belongs to the technical field of surface evapotranspiration evaluation. Background Art

[0002] The terrestrial water cycle refers to the process in which water enters the atmosphere through evaporation and transpiration on the land surface, then cools and condenses in the atmosphere to form precipitation, and finally returns to the land surface in the form of surface runoff or groundwater. This process not only maintains the water balance of terrestrial ecosystems, but also has a profound impact on climate, soil, vegetation, etc. Understanding the process and laws of the terrestrial water cycle will help us better manage and utilize water resources and respond to challenges such as climate change and natural disasters. At the same time, the study of the terrestrial water cycle also provides important scientific basis and technical support for production practices in agriculture, forestry, water conservancy and other fields.

[0003] In the complex process of terrestrial water cycle, precipitation cycle rate plays a vital role. This concept specifically refers to the proportion of local evaporated water vapor that contributes to local precipitation, which deeply reveals the intensity of land-atmosphere interaction in the region. Among the many components of precipitation recycling, vegetation evapotranspiration precipitation recycling is particularly critical. Accurately quantifying and evaluating the amount of vegetation evapotranspiration water vapor cycle in a region has far-reaching significance in many aspects: it can not only deepen our understanding of the regional water cycle mechanism, but also provide a scientific basis for optimizing the management and planning of water resources, while helping us better respond to the challenges of climate change, protect the fragile ecological environment, and promote the continuous progress of related scientific research and teaching activities. However, at present, we have not yet established a set of standard quantitative methods to accurately evaluate the amount of vegetation evapotranspiration water vapor cycle in a region, and we also lack an effective quantitative evaluation method to evaluate the specific impact of vegetation evapotranspiration water vapor cycle on regional available water resources. Summary of the invention

[0004] The present invention aims to solve a key problem in the current technical field: the lack of a standard quantitative method to evaluate the regional vegetation evapotranspiration water vapor cycle and the specific impact of the hydrological cycle in which the vegetation evapotranspiration water vapor participates on the regional available water resources. To this end, the present invention proposes a quantitative assessment method specifically for assessing the impact of the vegetation evapotranspiration water vapor cycle on the regional available water resources. The specific implementation plan is summarized as follows:

[0005] The assessment method of the impact of vegetation evapotranspiration on regional available water resources includes:

[0006] Step 1: According to the surface water loss data of the area to be studied, determine the proportion of vegetation evapotranspiration and the amount of precipitation recovery contributed by surface water loss in the area;

[0007] Step 2: Determine the vegetation evapotranspiration precipitation data of the vegetation evapotranspiration water vapor that contributes to the precipitation in the area to be studied according to the precipitation recovery amount and the vegetation evapotranspiration ratio;

[0008] Step 3: determining the original available water resource data of the area to be studied based on the precipitation data of the area to be studied, determining the precipitation data under the condition of water vapor circulation without vegetation evapotranspiration based on the vegetation evapotranspiration precipitation data, and determining the first available water resource data of the area to be studied;

[0009] Step 4: Determine the contribution rate of the vegetation evaporation water vapor cycle to the available water resource data of the area to be studied based on the original available water resource data and the first available water resource data, and quantitatively evaluate the impact of the vegetation evaporation water vapor cycle on the regional available water resources based on the contribution rate.

[0010] Preferably, the surface water loss data is the sum of soil evapotranspiration data, interception loss data, vegetation evapotranspiration data and snow sublimation data.

[0011] Preferably, determining the vegetation evapotranspiration ratio specifically includes:

[0012] The ratio of the vegetation evapotranspiration data to the surface water loss data is recorded as the vegetation evapotranspiration ratio.

[0013] Preferably, determining the amount of precipitation recovery contributed by surface water loss in the region specifically includes:

[0014] Acquiring meteorological data of the area to be studied;

[0015] The meteorological data is input into a water vapor tracking model to determine the amount of precipitation recovery contributed by surface water loss in the study area.

[0016] Preferably, the meteorological data includes:

[0017] Horizontal radial wind, zonal wind, specific humidity, surface pressure, water vapor flux, precipitation and evaporation.

[0018] Preferably, the step 2 specifically includes:

[0019] The product of the vegetation evapotranspiration ratio and the precipitation recovery amount is recorded as the vegetation evapotranspiration precipitation data of the contribution of vegetation evapotranspiration water vapor to the precipitation in the area to be studied.

[0020] Preferably, determining the original available water resource data of the area to be studied based on the precipitation data of the area to be studied specifically includes:

[0021] Determining actual evapotranspiration data of the area to be studied based on potential evapotranspiration data, precipitation data and vegetation coverage data of the area to be studied;

[0022] The original available water resource data of the area to be studied is determined according to the actual evapotranspiration data and the precipitation data.

[0023] Preferably, determining precipitation data under the condition of water vapor circulation without vegetation evapotranspiration according to the vegetation evapotranspiration precipitation data, and determining the first available water resource amount data of the area to be studied, specifically includes:

[0024] Determine the precipitation data of the area to be studied under the condition of no vegetation evapotranspiration water vapor cycle in the area to be studied according to the precipitation data and vegetation evapotranspiration precipitation data of the area to be studied;

[0025] The first available water resource amount data of the area to be studied is determined according to the precipitation data and the actual evapotranspiration data under the water vapor cycle condition without vegetation evapotranspiration in the area to be studied.

[0026] Preferably, step 4 specifically includes:

[0027] Determine the difference between the original available water resource quantity data and the first available water resource quantity data;

[0028] The ratio of the difference to the original available water resource data is recorded as the contribution rate of vegetation evaporation water vapor cycle to the available water resource data of the area to be studied.

[0029] Preferably, the actual evapotranspiration data is calculated according to the Budyko framework.

[0030] Beneficial effects: The method for evaluating the impact of regional vegetation evapotranspiration water vapor cycle on regional available water resources created by the present invention fills the gap in current research on quantifying the impact of vegetation evapotranspiration water vapor cycle on regional water resources. Through this method, the contribution rate of vegetation in a specific area to regional available water resources through evapotranspiration can be accurately quantified, providing a scientific basis for evaluating the effects of ecological engineering and the impact of land use changes on hydrological cycle and available water resources. Specifically, the beneficial effects of the present invention include:

[0031] (1) Improving the scientific nature of water resources management: By quantifying the evapotranspiration water vapor cycle, water resources managers can more accurately understand the circulation patterns and dynamic changes of water resources in the region, and provide data support for formulating reasonable water resources allocation, protection and utilization strategies.

[0032] (2) Promote the scientific nature of ecological engineering evaluation: Ecological engineering construction is often accompanied by changes in vegetation cover, which in turn affects regional evapotranspiration and precipitation recycling. The method of the present invention can quantify the specific impact of these changes on precipitation recycling, providing quantitative indicators for evaluating the actual effects and ecological benefits of ecological engineering.

[0033] (3) Enhance the research capabilities of climate change adaptation: Climate change has a significant impact on the water cycle. As an important part of the water cycle, the changes in the evapotranspiration of vegetation play an important role in the recycling of precipitation. The method of the present invention helps to deeply understand the interaction between vegetation and water cycle under the background of climate change, and provides theoretical support for the formulation of adaptive measures to cope with climate change.

[0034] (4) Promote the development of hydrological cycle research: The proposal of this invention not only enriches the theoretical framework of hydrological cycle research, but also provides new perspectives and tools for subsequent research. By continuously improving and applying this method, the understanding of global and regional hydrological cycle mechanisms will be further enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic flow chart of the method for evaluating the impact of the vegetation evapotranspiration water vapor cycle on the available water resources in a region of the present invention;

[0036] Figure 2 This is a verification diagram of the actual evaporation simulation results of the Budyko framework in the second embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with specific implementation methods. It should be understood that the specific implementation methods described here are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0038] Embodiment 1

[0039] In one embodiment, Figure 1 As shown in Figure 1, the quantitative assessment method for the impact of vegetation evapotranspiration on regional available water resources includes:

[0040] Step 1: According to the surface water loss data of the area to be studied, determine the proportion of vegetation evapotranspiration and the amount of precipitation recovery contributed by surface water loss in the area;

[0041] Specifically, in the embodiment of the present invention, the first area as the study area is divided into a plurality of regional units. Subsequently, surface water loss data of each regional unit is collected.

[0042] In the embodiment of the present invention, the surface water loss data is evaporation data, specifically the sum of soil evapotranspiration data, interception loss data, vegetation evapotranspiration data and snow sublimation data.

[0043] Furthermore, the proportion of vegetation evapotranspiration in the area to be studied is determined, including:

[0044] The ratio of vegetation evapotranspiration data to surface water loss data is recorded as the vegetation evapotranspiration ratio.

[0045] In the embodiment of the present invention, the vegetation evapotranspiration ratio of each regional unit ( ) is calculated as follows:

[0046]

[0047] Where:

[0048] Indicates regional unit Vegetation evapotranspiration data;

[0049] Indicates regional unit Soil evapotranspiration data;

[0050] Indicates regional unit Interception loss data;

[0051] Indicates regional unit Snow sublimation data;

[0052] Indicates regional unit area.

[0053] Furthermore, the amount of precipitation recovery contributed by the loss of surface water in the region is determined, specifically including: determining the precipitation data converted by evapotranspiration in the region to be studied; obtaining meteorological data of the region to be studied; and inputting the meteorological data into the water vapor tracking model to determine the amount of precipitation recovery contributed by the loss of surface water in the region to be studied.

[0054] Among them, meteorological data include: horizontal radial wind, zonal wind, specific humidity, surface pressure, water vapor flux, precipitation and evaporation.

[0055] Specifically, in the embodiment of the present invention, the WAM-2Layers model is used to track the water vapor trajectory in the precipitation tracing area, i.e., the area to be studied, and the data of evapotranspiration converted into precipitation in the area is calculated for each unit in the area to be studied ( ), compared with some Lagrangian methods such as FLEXPART (Flexible Particle Dispersion Model) and HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) that track humidity, the WAM2Layers model tracks the moisture of actual precipitation on the ground, while the Lagrangian method tracks the moisture released in the air rather than the actual precipitation observed on the ground. These characteristics make the WAM-2Layers model more suitable for research based on ground precipitation.

[0056] The WAM-2Layers model is used to track the backward water vapor trajectory in the precipitation tracing area, i.e. the area to be studied. Specifically, the horizontal radial wind ( ), zonal wind ( ), specific humidity ( ), surface pressure, water vapor flux, precipitation ( ) and evaporation ( ) data as the input data of the WAM-2Layers model, to track the evaporation data entering the air, and calculate the precipitation data converted from the evaporation tracked by the model in each regional unit ( ), quantify the source-sink relationship of water in the study area, and the formula used in the model is as follows:

[0057] Where:

[0058] Indicates the atmospheric humidity of the bottom layer being marked;

[0059] Indicates time;

[0060] and Respectively represent the latitude ( ) and longitude ( )’s wind component;

[0061] and They represent the evaporation entering the bottom layer and the precipitation leaving the bottom layer respectively;

[0062] represents the residual;

[0063] Represents the vertical moisture transport between the bottom and top layers.

[0064] Step 2: According to the precipitation recovery amount and the proportion of vegetation evapotranspiration, determine the vegetation evapotranspiration precipitation data that the vegetation evapotranspiration water vapor contributes to the precipitation in the study area;

[0065] Further, step 2 specifically includes:

[0066] The product of the vegetation evapotranspiration ratio and the precipitation recovery data is recorded as the vegetation evapotranspiration precipitation data contributed by the vegetation evapotranspiration water vapor to the study area.

[0067] Specifically, in the embodiment of the present invention, the precipitation data converted from the evapotranspiration tracked by the model in each regional unit in step 1 is collected ( ),Will and Multiply by to get the area unit The precipitation data converted from the regional vegetation evapotranspiration back to the regional ground ( ) is the vegetation evapotranspiration precipitation data, and the formula used is as follows:

[0068]

[0069] Where:

[0070] It represents the vegetation evapotranspiration precipitation data that the vegetation evapotranspiration water vapor contributes to the study area.

[0071] Step 3: determine the original available water resource data of the area to be studied based on the precipitation data of the area to be studied, determine the precipitation data under the condition of water vapor circulation without vegetation evapotranspiration based on the vegetation evapotranspiration precipitation data, and determine the first available water resource data of the area to be studied;

[0072] Furthermore, step 3 specifically includes:

[0073] Determine the actual evapotranspiration data of the area to be studied based on the potential evapotranspiration data, precipitation data and vegetation coverage data of the area to be studied;

[0074] Specifically, in this embodiment, the Budyko framework is used in combination with the precipitation data of the area to be studied ( ), potential evapotranspiration data ( ) to calculate the actual evapotranspiration data ( ), the budyko framework formula is as follows:

[0075]

[0076] Where:

[0077] is the actual evapotranspiration data of the area to be studied;

[0078] is the potential evapotranspiration data of the area to be studied, which is the maximum possible evapotranspiration under given meteorological conditions;

[0079] is the precipitation data of the area to be studied;

[0080] is the parameter to be solved, which reflects the influence of regional hydrological characteristics, such as soil, vegetation, topography, etc. on the evapotranspiration process;

[0081] Specifically, in actual operation, we first use the existing actual evapotranspiration data, potential evapotranspiration data, and precipitation data, and substitute these data into the Budyko framework formula through iteration or other numerical methods to calculate the parameters of the area to be studied. The numerical value of .

[0082] To describe more precisely The relationship between vegetation coverage and regional hydrological characteristics was further simplified by introducing vegetation coverage ( ) as a prediction Specifically, construct The regression relationship with vegetation coverage data is shown in the following formula:

[0083]

[0084] Where:

[0085] and Represents the regression equation coefficient, obtained through regression analysis, used to describe and( ) linear relationship between them; Indicates vegetation coverage.

[0086] It is worth noting that before establishing the above regression relationship, a series of These The values ​​are related to the vegetation coverage during the same period ( ) data were used in regression analysis to solve and Once you have a proven and value, this regression relationship can be used to predict the vegetation cover change in the area. Values ​​(as long as there is vegetation coverage data after the vegetation condition changes in the area), and then these Substitute the value into the Budyko framework formula to update the actual evapotranspiration data ( ).

[0087] In this way, not only the calculation The efficiency and accuracy of the value also make the Budyko framework more flexible and extensive in practical applications.

[0088] Specifically, in this embodiment, the formula for calculating the actual evapotranspiration data using the Budyko framework is updated as follows:

[0089]

[0090] Input potential evapotranspiration data into the updated Budyko framework ( )Precipitation data( ) and vegetation coverage data ( ) Calculate actual evapotranspiration data and verify it.

[0091] Subsequently, the original available water resources data of the area to be studied are determined based on the actual evapotranspiration data and precipitation data.

[0092] Specifically, in this embodiment, the original available water resources data of the area to be studied is calculated by using the precipitation data minus the actual evapotranspiration data calculated by the updated Budyko framework ( ), The calculation of is as follows:

[0093]

[0094] Represents the original available water resources data of the area to be studied.

[0095] Determine the precipitation data of the area to be studied under the condition of no vegetation evapotranspiration water vapor cycle according to the precipitation data of the area to be studied and the vegetation evapotranspiration precipitation data;

[0096] Specifically, in this embodiment, the precipitation data ( ) minus vegetation evapotranspiration precipitation data ( ) is recorded as the precipitation data under the condition of no vegetation evapotranspiration water vapor cycle in the study area ( ), the formula is as follows:

[0097]

[0098] Where: Represents precipitation data under conditions of water vapor circulation without vegetation evapotranspiration.

[0099] Subsequently, the first available water resource data of the area to be studied is determined according to the precipitation data under the water vapor cycle condition of no vegetation evapotranspiration and the actual evapotranspiration data of the area to be studied.

[0100] Specifically, in this embodiment, the calculation of the first available water resource amount data is shown as follows:

[0101]

[0102] Where:

[0103] It represents the first available water resources data, which represents the available water resources data after removing the vegetation evaporation and return precipitation.

[0104] Step 4: Determine the contribution rate of the vegetation evaporation water vapor cycle to the available water resources data of the study area based on the original available water resources data and the first available water resources data, and quantitatively evaluate the impact of the vegetation evaporation water vapor cycle on the regional available water resources based on the contribution rate.

[0105] Further, determining the difference between the original available water resource quantity data and the first available water resource quantity data;

[0106] The ratio of the difference to the original available water resources data is recorded as the contribution rate of vegetation evaporation water vapor cycle to the available water resources data of the study area.

[0107] Specifically, in this embodiment, the calculation formula for the contribution rate of vegetation evaporation water vapor cycle to the available water resources data of the study area is as follows:

[0108]

[0109] Where:

[0110] It represents the contribution rate of vegetation evaporation water vapor cycle to the available water resources data in the study area.

[0111] Finally, the contribution rate is used to quantitatively evaluate the impact of the vegetation evapotranspiration water vapor cycle on the regional available water resources. Specifically, the contribution rate directly reflects the relative importance of the vegetation evapotranspiration water vapor cycle in the regional water resources cycle. The higher the contribution rate, the stronger the role of the vegetation evapotranspiration water vapor cycle in replenishing and regulating the regional available water resources, and the greater its contribution to maintaining the regional hydrological balance and ecological balance. Conversely, a low contribution rate may mean that the vegetation evapotranspiration water vapor cycle plays a relatively limited role in the water resources cycle in the region, or there are other more important water resources replenishment and regulation mechanisms.

[0112] Through this quantitative assessment process, we can more clearly understand the important role of vegetation evapotranspiration water vapor cycle in regional water resources management, thus providing a strong basis for formulating scientific and reasonable water resources protection and utilization strategies. At the same time, this assessment result helps to better understand the complexity and diversity of regional hydrological cycles and provide new ideas and methods for future water resources research and management.

[0113] The method for evaluating regional vegetation evapotranspiration water vapor cycle created by the present invention fills the gap in current research on quantifying the impact of vegetation evapotranspiration precipitation recycling on available water resources. Through this method, the contribution rate of vegetation in a specific area to the regional available water resources through evapotranspiration can be accurately quantified, providing a scientific basis for evaluating the effects of ecological engineering and the impact of land use changes on the hydrological cycle and available water resources. Specifically, the beneficial effects of the present invention include:

[0114] (1) Improving the scientific nature of water resources management: By quantifying the evapotranspiration water vapor cycle, water resources managers can more accurately understand the circulation patterns and dynamic changes of water resources in the region, and provide data support for formulating reasonable water resources allocation, protection and utilization strategies.

[0115] (2) Promote the scientific nature of ecological engineering evaluation: Ecological engineering construction is often accompanied by changes in vegetation cover, which in turn affects regional evapotranspiration and precipitation recycling. The method of the present invention can quantify the specific impact of these changes on precipitation recycling, providing quantitative indicators for evaluating the actual effects and ecological benefits of ecological engineering.

[0116] (3) Enhance the research capabilities of climate change adaptation: Climate change has a significant impact on the water cycle. As an important part of the water cycle, the changes in the evapotranspiration of vegetation play an important role in the recycling of precipitation. The method of the present invention helps to deeply understand the interaction between vegetation and water cycle under the background of climate change, and provides theoretical support for the formulation of adaptive measures to cope with climate change.

[0117] (4) Promote the development of hydrological cycle research: The proposal of this invention not only enriches the theoretical framework of hydrological cycle research, but also provides new perspectives and tools for subsequent research. By continuously improving and applying this method, the understanding of global and regional hydrological cycle mechanisms will be further enhanced.

[0118] Embodiment 2:

[0119] This example takes the Loess Plateau in China as an example to obtain the precipitation, actual evapotranspiration, potential evapotranspiration, vegetation evapotranspiration, horizontal radial wind, zonal wind, specific humidity, surface pressure and water vapor flux data in July 2020. The Loess Plateau is divided into 6 regions: agricultural irrigation area, earth and rock mountain area, hilly gully area, plateau gully area, river valley plain area and desert mountain area. The agricultural irrigation area covers an area of ​​48,962 km 2 The area of ​​soil and rocky mountainous area is 89,205.5 km 2 The plateau gully area is 205723 km 2 , hilly and gully area 137392.1 km 2 , valley plain area 57991.1 km 2 , Desert Mountain Area 82371 km 2 .

[0120] Collect the actual evapotranspiration and vegetation evapotranspiration data of each sub-area. This example calculates the vegetation evapotranspiration ratio of each sub-area. The evapotranspiration dataset selected is GLEAM (Global Land Evaporation Amsterdam Model), and the evapotranspiration of each sub-region in the study area in July 2020 is calculated. The values ​​of are shown in Table 1;

[0121] Table 1: Percentage of vegetation evapotranspiration in each sub-region

[0122]

[0123] The precipitation, actual evapotranspiration, horizontal radial wind, zonal wind, specific humidity, surface pressure and water vapor flux data in the ERA5 data (the fifth generation of the European Center for Medium-Range Weather Forecasts climate reanalysis data) were input into the water vapor tracking model to track the water vapor source of precipitation in the Loess Plateau in July 2020. The output results of the water vapor tracking model were statistically analyzed to calculate the vegetation evapotranspiration precipitation data for each sub-area. The calculation results are shown in Table 2. It can be seen that the vegetation evapotranspiration precipitation in the agricultural irrigation area and desert mountain area with low vegetation coverage is less than that in other areas. The total evapotranspiration precipitation in the plateau gully area is the largest, but the area with the largest average evapotranspiration precipitation in a single grid point in each sub-area is the river valley plain area:

[0124] Table 2: Vegetation evapotranspiration precipitation data for each sub-region

[0125]

[0126] The actual evapotranspiration data, potential evapotranspiration data, precipitation data, and vegetation coverage data from 2000 to 2020 were brought into the Budyko framework to calculate the parameters of each study area. The data were used to determine the parameters of each partition using regression analysis. The regression equation coefficients and The results are shown in Table 3. The actual evapotranspiration simulated by the Budyko framework and the actual evapotranspiration input are tested as follows Figure 2 As shown, The value 0.94 is greater than 0.7, indicating that the simulation results of the Budyko framework are good.

[0127] Table 3: Parameters of each partition Regression equation coefficients

[0128]

[0129] Input the precipitation, potential evapotranspiration, vegetation cover, and vegetation evapotranspiration precipitation of each sub-region in 2020 into the constructed Budyko framework to calculate the original available water resources ( )、First available water resources ( ) and the contribution rate of vegetation evaporation cycle to the available water resources data of the study area ( ), the input data are shown in Table 4, and the calculation results are shown in Table 5. Among the six sub-regions of the Loess Plateau, the river valley plain area has the highest available water resources, the desert mountain area has the lowest available water resources, and the vegetation evapotranspiration water vapor cycle contributes an average of 9% of the available water resources to the Loess Plateau.

[0130] Table 4: Budyko framework input data

[0131]

[0132] Table 5: Calculation results of the contribution of vegetation evapotranspiration water vapor cycle to available water in each sub-area

[0133]

[0134] The method for evaluating the impact of regional vegetation evapotranspiration water vapor cycle on regional available water resources created by the present invention fills the gap in current research on quantifying the impact of vegetation evapotranspiration water vapor cycle on regional water resources. Through this method, the contribution rate of vegetation in a specific area to regional available water resources through evapotranspiration can be accurately quantified, providing a scientific basis for evaluating the effects of ecological engineering and the impact of land use changes on hydrological cycle and available water resources.

[0135] The above are only several embodiments of the present invention and are not intended to limit the present invention in any form. Although the present invention is disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any technician familiar with the profession, without departing from the scope of the technical solution of the present invention, using the above disclosed technical content to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for assessing the impact of vegetation evapotranspiration on regional water resources availability, characterized in that: include: Step 1: According to the surface water loss data of the area to be studied, determine the proportion of vegetation evapotranspiration and the amount of precipitation recovery contributed by surface water loss in the area; Step 2: Determine the vegetation evapotranspiration precipitation data of the vegetation evapotranspiration water vapor that contributes to the precipitation in the area to be studied according to the precipitation recovery amount and the vegetation evapotranspiration ratio; Step 3: determining the original available water resource data of the area to be studied based on the precipitation data of the area to be studied, determining the precipitation data under the condition of water vapor circulation without vegetation evapotranspiration based on the vegetation evapotranspiration precipitation data, and determining the first available water resource data of the area to be studied; Step 4: Determine the contribution rate of the vegetation evaporation water vapor cycle to the available water resource data of the area to be studied based on the original available water resource data and the first available water resource data, and quantitatively evaluate the impact of the vegetation evaporation water vapor cycle on the available water resource of the area based on the contribution rate; Determining the contribution rate specifically includes: Determine the difference between the original available water resource quantity data and the first available water resource quantity data; The ratio of the difference to the original available water resource data is recorded as the contribution rate of vegetation evaporation water vapor cycle to the available water resource data of the area to be studied.

2. The evaluation method according to claim 1, characterized in that: The surface water loss data is the sum of soil evapotranspiration data, interception loss data, vegetation evapotranspiration data and snow sublimation data.

3. The evaluation method according to claim 2, characterized in that: Determine the percentage of vegetation evapotranspiration, including: The ratio of the vegetation evapotranspiration data to the surface water loss data is recorded as the vegetation evapotranspiration ratio.

4. The evaluation method according to claim 1, characterized in that: Determine the amount of precipitation recovery in the area contributed by surface water loss, including: Acquiring meteorological data of the area to be studied; The meteorological data is input into a water vapor tracking model to determine the amount of precipitation recovery contributed by surface water loss in the study area.

5. The evaluation method according to claim 4, characterized in that: The meteorological data include: Horizontal radial wind, zonal wind, specific humidity, surface pressure, water vapor flux, precipitation and evaporation.

6. The evaluation method according to claim 1, characterized in that: The step 2 specifically includes: The product of the vegetation evapotranspiration ratio and the precipitation recovery amount is recorded as the vegetation evapotranspiration precipitation data of the contribution of vegetation evapotranspiration water vapor to the precipitation in the area to be studied.

7. The evaluation method according to claim 1, characterized in that: According to the precipitation data of the area to be studied, the original available water resources data of the area to be studied is determined, specifically including: Determining actual evapotranspiration data of the area to be studied based on potential evapotranspiration data, precipitation data and vegetation coverage data of the area to be studied; The original available water resource data of the area to be studied is determined according to the actual evapotranspiration data and the precipitation data.

8. The evaluation method according to claim 7, characterized in that: Determining precipitation data under the condition of water vapor circulation without vegetation evapotranspiration according to the vegetation evapotranspiration precipitation data, and determining the first available water resource amount data of the area to be studied, specifically including: Determine the precipitation data of the area to be studied under the condition of no vegetation evapotranspiration water vapor cycle in the area to be studied according to the precipitation data and vegetation evapotranspiration precipitation data of the area to be studied; The first available water resource amount data of the area to be studied is determined according to the precipitation data and the actual evapotranspiration data under the water vapor cycle condition without vegetation evapotranspiration in the area to be studied.

9. The evaluation method according to claim 7, characterized in that: The actual evapotranspiration data are calculated according to the Budyko framework.

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