Three-dimensional utilization evaluation method for light complementation wind prevention and sand fixation configuration mode of desert forest

Abstract

The invention relates to the technical field of desertification prevention and control, in particular to a three-dimensional utilization evaluation method for a light complementation wind prevention and sand fixation configuration mode of a desert forest. Obtaining wind prevention and sand fixation vegetation evaluation indexes of different configuration modes under the photovoltaic panel of the target sand area; the evaluation indexes comprise a plant growth index, a soil index and a wind prevention and sand fixation index parameter, obtaining a weight value of each evaluation index, and obtaining a score corresponding to each configuration mode according to the weight value of each evaluation index; and evaluating the wind prevention and sand fixation vegetation of the configuration mode according to the score of each configuration mode. According to the method, the optimal configuration mode of land three-dimensional utilization of the photovoltaic power station in the desert area is formed through scientific proportioning of different desert plants, so that effective support can be provided for collaborative development of construction of the photovoltaic power station in the desert area and ecological environment protection in cooperation with construction and distribution of the photovoltaic power station in the desert area.

Description

Technical Field

[0001] The invention relates to the technical field of desertification prevention and control, and in particular to a three-dimensional utilization evaluation method for a forest-light complementary windbreak and sand fixation configuration mode in a sandy area. Background Art

[0002] Solar energy is a clean, pollution-free renewable energy source. It is the best choice for countries around the world to cope with energy shortages and climate change. my country's solar energy resources are particularly abundant. In recent years, China's solar energy industry has risen rapidly. Currently, vigorously developing photovoltaic and other renewable energy sources is a strategic choice for my country to cope with climate change and build an energy security system.

[0003] The rapid development of photovoltaic power stations, especially their large-scale layout in the arid and semi-arid areas of northwest my country, has led to increasingly prominent contradictions with the protection of the originally fragile northwest desert ecosystem. How to use photovoltaic power stations to achieve efficient utilization of renewable clean energy while effectively protecting the originally fragile northwest desert ecosystem, repairing the disturbance and damage to the ecological environment caused by the initial construction of photovoltaic power stations, and even further improving the stability of the desert ecosystem are issues that need to be urgently addressed in the current development of photovoltaic clean energy.

[0004] Photovoltaic power generation is in line with the development direction of the energy industry. my country's photovoltaic power stations are most widely built in the arid northwest region, but the ecological environment in the arid northwest region is relatively fragile, and the sandy areas are windy and sandy. The wind and sand flow gathers and accelerates under the panels and forms vortices in front of and behind the panels, forming wind erosion landforms in front of the photovoltaic panels and accumulation landforms on both sides, resulting in severe wind erosion under the photovoltaic panels, in front of the panels, and between the panels. Therefore, suitable plants are installed under the photovoltaic panels in the sandy areas to play a role in preventing wind and fixing sand, forming forest-light complementarity in the sandy areas. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention provides a three-dimensional utilization evaluation method for the windbreak and sand fixation configuration mode of forest-light complementary in sandy areas. The scheme includes: obtaining evaluation indicators of windbreak and sand fixation vegetation in different configuration modes under photovoltaic panels in target sandy areas; the evaluation indicators include: plant growth indicators, soil indicators and windbreak and sand fixation index parameters, obtaining the weight value of each evaluation indicator, and obtaining the score corresponding to each configuration mode according to the weight value of each evaluation indicator; and evaluating the windbreak and sand fixation vegetation of the configuration mode according to the score of each configuration mode. The present invention forms the optimal configuration mode for the three-dimensional utilization of land in sandy areas photovoltaic power stations through the scientific ratio of different sand-dwelling plants, thereby coordinating the construction distribution of photovoltaic power stations in sandy areas, and can provide effective support for the coordinated development of photovoltaic power station construction in sandy areas and ecological environmental protection.

[0006] The present invention adopts the following technical scheme, a three-dimensional utilization evaluation method of a forest-light complementary windbreak and sand fixation configuration mode in a sandy area, comprising:

[0007] Obtain evaluation indicators of windbreak and sand fixation vegetation under different configuration modes of photovoltaic panels in target sandy areas;

[0008] The evaluation indicators include: plant growth indicators, soil indicators and windbreak and sand fixation parameter indicators.

[0009] Obtain the weight value of each evaluation indicator, and obtain the score corresponding to each configuration mode according to the weight value of each evaluation indicator;

[0010] The windbreak and sand-fixing vegetation of each configuration pattern is evaluated according to the score of that configuration pattern.

[0011] Furthermore, the plant growth indicators include: plant coverage, height, frequency and diversity indicators under the board.

[0012] Furthermore, the soil index includes: physical property index and chemical property index;

[0013] The physical property indicators include: soil moisture content, bulk density, maximum water holding capacity, capillary water holding capacity, minimum water holding capacity, non-capillary pores, capillary pores and total porosity; the chemical property indicators include: available phosphorus, available potassium, alkaline-hydrolyzable nitrogen, total phosphorus, total potassium, total nitrogen and organic matter.

[0014] Furthermore, the wind-proof and sand-fixing parameter indicators include: wind speed pulsation characteristics, wind speed flow field characteristics, surface roughness, sand transport rate, sand blocking effect, cumulative sand transport rate height, erosion rate, wind-proof efficiency and protection distance.

[0015] Furthermore, the score corresponding to each configuration mode is obtained according to the weight value of each evaluation indicator, including:

[0016] The weighted sum is performed according to the weight values ​​of the corresponding evaluation indicators in each configuration mode to obtain the score of each configuration mode.

[0017] Furthermore, the windbreak and sand fixation vegetation of each configuration mode is evaluated according to the score of the configuration mode, specifically:

[0018] The score of each configuration mode is compared with the set threshold. When the score is greater than or equal to the set threshold, the windbreak and sand fixation vegetation corresponding to the configuration mode is reasonable.

[0019] When the score is less than the set threshold, the windbreak and sand fixation vegetation corresponding to the configuration mode is unreasonable.

[0020] The beneficial effects of the present invention are as follows: the present invention realizes a multi-dimensional comprehensive evaluation of the comprehensive land utilization efficiency of the configuration mode through the vegetation growth conditions, soil environment, windbreak and sand fixation effects and land utilization efficiency corresponding to the target area, which helps to better utilize the limited land in the photovoltaic power station in the sandy area to achieve the maximum benefit, and provides a more scientific basis for decision makers, so that they can more accurately select the configuration mode that best suits the target observation area to achieve the maximum three-dimensional land utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 It is a flow chart of a three-dimensional utilization evaluation method of a forest-light complementary windbreak and sand fixation configuration mode in a sandy area according to an embodiment of the present invention; DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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 ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Photovoltaic power generation is combined with vegetation restoration to carry out ecological restoration in desertified areas, aiming to reduce water evaporation through the shading effect of photovoltaic panels, and use the space under the photovoltaic panels for vegetation planting to improve soil structure and increase vegetation coverage, thereby achieving the purpose of windbreak and sand fixation and ecological restoration. This involves the structural design of the forest-light complementary system, plant configuration, soil improvement methods, water resource management technology and other aspects. The windbreak and sand fixation effect of the forest-light complementary system in sandy areas is defined from these perspectives, so as to better promote vegetation growth, improve soil structure and achieve ecological restoration in desert areas. Based on this, the present invention establishes a corresponding evaluation system by acquiring indicators under the forest-light complementary mode of photovoltaic power stations in sandy areas. A flow chart of a three-dimensional utilization evaluation method for a forest-light complementary windbreak and sand fixation configuration mode in sandy areas according to an embodiment of the present invention is shown in FIG. Figure 1 As shown, including:

[0025] Obtain windbreak and sand fixation vegetation evaluation indicators of different configuration modes under photovoltaic panels in the target sand area; the evaluation indicators include: plant growth indicators, soil indicators and windbreak and sand fixation parameter indicators;

[0026] Among them, plant growth indicators include: plant coverage, height, frequency and diversity indicators under the board; soil indicators include: physical property indicators and chemical property indicators; physical property indicators include: soil moisture content, bulk density, maximum water holding capacity, capillary water holding capacity, minimum water holding capacity, non-capillary pores, capillary pores and total porosity; chemical property indicators include: available phosphorus, available potassium, alkaline nitrogen, total phosphorus, total potassium, total nitrogen and organic matter; windbreak and sand fixation parameter indicators include: wind speed pulsation characteristics, wind speed flow field characteristics, surface roughness, sand transport rate, sand blocking effect, cumulative sand transport rate height, erosion rate, windbreak efficiency and protection distance.

[0027] The embodiment of the present invention further provides a method for obtaining some of the wind and sand fixation parameter indicators, including:

[0028] Wind speed pulsation characteristics: In the embodiment of the present invention, the wind speed pulsation characteristics are analyzed from three aspects: average wind speed, wind speed pulsation, and wind speed pulsation intensity. The average wind speed is analyzed with a data length of 10 minutes. The average wind speed is used to reflect the overall change trend of the wind speed; the wind speed pulsation value is the difference between the instantaneous wind speed (u) and the average wind speed The wind speed pulsation intensity is expressed by the root mean square of the wind speed pulsation value:

[0029]

[0030] Where: u' is the wind speed pulsation; u is the instantaneous wind speed (unit: m / s), is the average wind speed (unit: m / s); n is the number of samples.

[0031] Wind velocity flow field characteristics: Kriging spatial interpolation method is widely used in the fields of topographic map contour interpolation, air flow velocity field spatial interpolation, soil, precipitation spatial mapping, etc. In the embodiment of the present invention, the Kriging spatial interpolation method in Sufer11.0 software is selected to combine the wind speed data at each observation point in the field for spatial interpolation processing, so as to obtain the wind velocity flow field characteristics of the target sand area.

[0032] Surface roughness: In the embodiment of the present invention, the least squares regression is used to obtain the wind speed profile fitting formula, and the wind speeds at five heights (10 cm, 30 cm, 50 cm, 100 cm and 200 cm) at the observation point are simulated with the wind speed profile equation to measure the roughness of the observation plot. The formula is as follows:

[0033] V h =a+bln(h)

[0034] h0=exp(-a / b)

[0035] Where: a, b are regression coefficients; V h is the wind speed at height h (unit: m / s), let V h=0 can be used to calculate the ground roughness (unit: cm).

[0036] Sediment transport rate: Sediment transport rate refers to the sum of the sediment transport rates collected by the sand collecting boxes on each layer of the sand collector in unit time. It is a common indicator for measuring the activity level of wind and sand in wind and sand observation. The calculation formula is as follows:

[0037]

[0038] Where: Q is the sediment transport rate (unit: g / (cm2·min)); Δt is the total observation time (unit: min); A is the cross-sectional area of ​​the sand inlet (unit: cm 2 );q n is the amount of sand collected in the nth layer of the sand collection box (unit: g), n = 1, 2...50.

[0039] Sand barrier effect: It indicates the percentage of sand transport in the sand barrier compared to the bare sand. It is a common indicator of the protective effect of sand barriers. The calculation formula is as follows:

[0040]

[0041] Where: F is the sand blocking effect (percentage %); q1 is the amount of sand collected in the sand barrier sample plot (unit: g); q0 is the amount of sand collected in the control sample plot (unit: g).

[0042] Cumulative sediment transport rate height: The cumulative sediment transport rate height indicates the height range in which the sediment transport rate accounts for a specific proportion of the total sediment transport rate. For example, the 50% cumulative sediment transport rate height is the height when the sediment transport rate reaches 50% of the total sediment transport rate. This indicator reflects the cumulative change characteristics of the sediment transport in the wind-sand flow structure and is often used to measure the changes in the wind-sand flow structure. In the embodiment of the present invention, four cumulative sediment transport rate heights of 50%, 70%, 80% and 90% can be selected as evaluation indicators.

[0043] Erosion rate: Surface erosion measurement Erosion depth and erosion intensity are common erosion parameters, and the calculation formula is:

[0044] h=h0-h1

[0045]

[0046] Among them, h is the erosion depth (unit: cm); j0 is the initial surface height (unit: cm); h1 is the surface height after a wind (unit: cm), r is the erosion rate (unit: cm / h), when r>0, it indicates accumulation; when r=0, it indicates erosion balance; when r<0, it indicates wind erosion.

[0047] Wind protection efficiency and protection distance: Wind protection efficiency refers to the extent to which the average wind speed at each observation point is reduced compared to the indicated wind speed in the wilderness under the influence of sand barriers or obstacles; based on field observation results, it is generally believed that the distance between the obstacle and the obstacle when the wind speed at the same height under the obstacle recovers to 20-50% of the indicated wind speed in the wilderness is the effective protection distance. Drawing on existing research results, in the embodiment of the present invention, the effective protection distance is determined by reducing the wilderness wind speed by 50%; the calculation expression of wind protection efficiency is:

[0048]

[0049] Where: E Hz V is the wind protection efficiency, which is the percentage of the average wind speed at the height z at a distance H before and after the sand barrier compared with the indicated wind speed in the wilderness; fz is the average wind speed at height z in the wilderness; V Hz is the average wind speed at a distance H before and after the sand barrier at a height of z.

[0050] Obtain the weight value of each evaluation indicator, and obtain the score corresponding to each configuration mode according to the weight value of each evaluation indicator;

[0051] In the embodiment of the present invention, a weighted sum is performed according to the weight values ​​of the corresponding evaluation indicators in each configuration mode to obtain the score of each configuration mode.

[0052] The windbreak and sand fixation vegetation of each configuration mode is evaluated according to the score of the configuration mode, specifically:

[0053] The score of each configuration mode is compared with the set threshold. When the score is greater than or equal to the set threshold, the windbreak and sand-fixing vegetation corresponding to the configuration mode is reasonable; when the score is less than the set threshold, the windbreak and sand-fixing vegetation corresponding to the configuration mode is unreasonable.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A three-dimensional utilization evaluation method for the forest-light complementary windbreak and sand fixation configuration mode in sandy areas, characterized in that: include: Obtain evaluation indicators of windbreak and sand fixation vegetation under different configuration modes of photovoltaic panels in target sandy areas; The evaluation indicators include: plant growth indicators, soil indicators and windbreak and sand fixation parameter indicators. Obtain the weight value of each evaluation indicator, and obtain the score corresponding to each configuration mode according to the weight value of each evaluation indicator; The windbreak and sand-fixing vegetation of each configuration pattern is evaluated according to the score of that configuration pattern.

2. The three-dimensional utilization evaluation method of the forest-light complementary windbreak and sand fixation configuration mode in sandy areas according to claim 1 is characterized by: The plant growth indicators include: plant coverage, height, frequency and diversity indicators under the board.

3. The three-dimensional utilization evaluation method of the forest-light complementary windbreak and sand fixation configuration mode in sandy areas according to claim 1 is characterized by: The soil indicators include: physical property indicators and chemical property indicators; The physical property indicators include: soil moisture content, bulk density, maximum water holding capacity, capillary water holding capacity, minimum water holding capacity, non-capillary pores, capillary pores and total porosity; the chemical property indicators include: available phosphorus, available potassium, alkaline-hydrolyzable nitrogen, total phosphorus, total potassium, total nitrogen and organic matter.

4. The three-dimensional utilization evaluation method of the forest-light complementary windbreak and sand fixation configuration mode in sandy areas according to claim 1 is characterized by: The wind-proof and sand-fixing parameter indicators include: wind speed pulsation characteristics, wind speed flow field characteristics, surface roughness, sand transport rate, sand blocking effect, cumulative sand transport rate height, erosion rate, wind-proof efficiency and protection distance.

5. The three-dimensional utilization evaluation method of the forest-light complementary windbreak and sand fixation configuration mode in sandy areas according to claim 1 is characterized by: The score of each configuration mode is obtained according to the weight value of each evaluation indicator, including: The weighted sum is performed according to the weight values ​​of the corresponding evaluation indicators in each configuration mode to obtain the score of each configuration mode.

6. The three-dimensional utilization evaluation method of the forest-light complementary windbreak and sand fixation configuration mode in sandy areas according to claim 1 is characterized by: The windbreak and sand fixation vegetation of each configuration mode is evaluated according to the score of the configuration mode, specifically: The score of each configuration mode is compared with the set threshold. When the score is greater than or equal to the set threshold, the windbreak and sand fixation vegetation corresponding to the configuration mode is reasonable. When the score is less than the set threshold, the windbreak and sand fixation vegetation corresponding to the configuration mode is unreasonable.

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