Structure-function-operation mechanism-based drought toughness evaluation method for regional water resource supply and demand system

Abstract

The invention discloses a structure-function-operation mechanism-based regional water resource supply and demand system drought toughness evaluation method. The method comprises the following steps of S1, establishing a regional water resource supply and demand system drought toughness evaluation model; s2, constructing a drought toughness evaluation index system of the regional water resource supply and demand system; S3, determining an evaluation standard of each index of the regional water resource supply and demand system in combination with the field condition of the research region; s4, optimizing and screening the indexes screened in the step S2 by using a principal component analysis method; s5, determining the comprehensive weight of the optimized and screened evaluation indexes in a mode of combining an analytic hierarchy process and an entropy evaluation method; and S6, on the basis of determining the comprehensive weight of the optimized and screened evaluation indexes, calculating the comprehensive toughness index of the regional water resource supply and demand system by using a fuzzy comprehensive evaluation method, and evaluating the drought toughness of the regional water resource supply and demand system.

Description

Technical Field

[0001] The present invention relates to the technical field of drought resilience assessment for regional water resource supply and demand systems, and in particular to a method for drought resilience assessment for regional water resource supply and demand systems based on a structure-function-operation mechanism. Background Art

[0002] Drought is a natural variation that lasts for a long time, affects a wide range of areas, causes serious losses, and occurs frequently. It has always been one of the most dangerous natural disasters, seriously affecting the progress and development of all human society. Affected by global climate change, global drought will seriously intensify in the next few decades. The frequency of extreme droughts with long duration, wide impact, and high intensity will increase significantly. Some local areas may experience a once-in-a-century drought or even break historical records. With the frequent occurrence of extreme drought events, the study of the comprehensive resilience of water supply and demand systems has become increasingly important.

[0003] With the gradual rise of system science, in 1973, American ecology professor Holly introduced "resilience" from engineering to ecology, which promoted the development of resilience in the field of ecology. In January 2005, the International Conference on Disaster Reduction proposed the important role of resilience in responding to disasters. Resilience began to be applied to urban systems as a new disaster prevention and reduction strategy. Water resources are one of the important natural resources supporting the sustainable development of cities. On the basis of urban resilience assessment, it is crucial to assess the resilience of the water resource supply and demand system under extreme drought.

[0004] Some existing water resource supply and demand system resilience assessment methods select overpressure ratio, the ratio of service capacity under threshold pressure to full load service capacity, and the degree to which service capacity decreases with increasing pressure as evaluation indicators; some construct a water resource system resilience evaluation index system from five aspects, including meteorology, hydrology, and engineering; some introduce the concepts of engineering resilience, ecological resilience, and evolutionary resilience, and construct an evaluation index system from the above three dimensions. The above studies have achieved the evaluation of the resilience of water resource systems under extreme drought to a certain extent, but the resilience evaluation indicators are mostly selected from the system structure level, ignoring the consideration of system functions and operating mechanisms. The main reason is that the evaluation indicators of functions and operating mechanisms are difficult to quantify. Summary of the invention

[0005] To solve the above problems, the present invention proposes a method for evaluating the drought resilience of a regional water resources supply and demand system based on a structure-function-operation mechanism, and establishes a drought resilience evaluation system for a regional water resources supply and demand system based on a structure-function-operation mechanism. The evaluation system includes multiple evaluation indicators at three criterion levels: stable structure, perfect functions, and recoverable operation mechanism. The grade standards of the evaluation indicators are quantified, and the comprehensive weights of the evaluation indicators are determined by combining the analytic hierarchy process and the entropy method to enhance their rationality. The fuzzy comprehensive evaluation method is used to evaluate the drought resilience of the regional water resources supply and demand system, thereby improving the accuracy of the evaluation.

[0006] The first embodiment of the present application proposes a method for evaluating drought resilience of a regional water resources supply and demand system based on a structure-function-operation mechanism, comprising the following steps:

[0007] Step S1, establishing a drought resilience evaluation model for the regional water resources supply and demand system, the evaluation model includes a target layer, which is used as the drought resilience layer of the regional water resources supply and demand system; a criterion layer, which includes three characteristic attributes: stable structure, perfect functions, and recoverable operation mechanism; and an indicator layer, which selects indicators that can reflect the stable structure, perfect functions, and recoverable operation mechanism based on the three characteristic attributes of the water resources supply and demand system;

[0008] Step S2, constructing a drought resilience evaluation index system for the regional water resources supply and demand system:

[0009] Step S21, determining the structural stability index of the regional water resources supply and demand system, wherein the selected index includes evaluating the structural stability of the regional water resources supply and demand system from the perspectives of the natural structure and social structure of the regional water resources supply and demand system;

[0010] Step S22, determining functional improvement indicators, the selected indicators evaluate the functional improvement of the regional water resources supply and demand system from the perspectives of production capacity, life security and production efficiency of the regional water resources supply and demand system;

[0011] Step S23, determining the recoverable index of the operation mechanism, and the selected index evaluates the recoverability of the operation mechanism of the regional water resources supply and demand system from the perspectives of the feedback mechanism of the natural subsystem of the regional water resources supply and demand system, the feedback mechanism of the social subsystem and the coupling mechanism between the two subsystems;

[0012] Step S3, determining the evaluation criteria of the drought resilience evaluation index of the regional water resources supply and demand system selected in the above step in combination with the actual situation of the study area;

[0013] Step S4, using principal component analysis to optimize the screening indicators;

[0014] Step S5, using a combination of analytic hierarchy process and entropy method to determine the comprehensive weight of the evaluation index after optimization and screening;

[0015] Step S6, based on the comprehensive weights of the evaluation indicators after optimization and screening, the comprehensive resilience index of the regional water resources supply and demand system is calculated using the fuzzy comprehensive evaluation method to evaluate the drought resilience of the regional water resources supply and demand system.

[0016] Preferably, the structural stability indicators include energy self-sufficiency rate, surface water resource change rate, total auxiliary energy ratio, water resource development and utilization rate, and water resource energy contribution rate.

[0017] Preferably, the functional improvement indicators include water resources energy value output density, water resources net energy value output rate, per capita water resources energy value utilization, water resources life security function ratio, water resources social stability function ratio, water resources employment security function ratio, water resources pension security function ratio, agricultural output energy value ratio, and industrial output energy value ratio.

[0018] Preferably, the recoverable indicators of the operation mechanism include water self-purification capacity, population density, environmental load rate, drought-affected area ratio, and energy sustainability index.

[0019] By adopting the above technical solutions, it is possible to evaluate the drought resilience of the regional water resources supply and demand system.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: based on the structure-function-operation mechanism indicator construction method, the energy value indicator is combined with the conventional indicator to construct a comprehensive resilience evaluation index system of the regional water resources supply and demand system under extreme drought, which is composed of the structural stability, functional perfection and recoverability of the operation mechanism of the water resources supply and demand system, making up for the shortcomings of the conventional indicators in insufficient description of the system operation status; the comprehensive weights of the evaluation indicators after optimization and screening are determined by combining the analytic hierarchy process and the entropy method in a subjective and objective manner, thereby improving the accuracy of the weights of the evaluation indicators after optimization and screening; finally, on the basis of determining the comprehensive weights of the evaluation indicators after optimization and screening, the fuzzy comprehensive evaluation method is used to calculate the comprehensive resilience index of the regional water resources supply and demand system, and the drought resilience of the regional water resources supply and demand system is evaluated. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A flow chart of a drought resilience assessment method for regional water resources supply and demand systems based on a structure-function-operation mechanism;

[0022] Figure 2 This is the CRI calculation result diagram of Chuxiong Prefecture’s water resources supply and demand system. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all 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] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0025] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0026] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0027] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0028] The optional embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0029] according to Figure 1 ,This application proposes a drought resilience assessment method for regional water resources supply and demand system based on structure-function-operation mechanism, including the following steps:

[0030] Step S1, establishing a drought resilience evaluation model for the regional water resources supply and demand system, the evaluation model includes a target layer, which is used as the drought resilience layer of the regional water resources supply and demand system; a criterion layer, which includes three characteristic attributes: stable structure, perfect functions, and recoverable operation mechanism; and an indicator layer, which selects indicators that can reflect the stable structure, perfect functions, and recoverable operation mechanism based on the three characteristic attributes of the water resources supply and demand system;

[0031] Step S2, constructing a drought resilience evaluation index system for the regional water resources supply and demand system:

[0032] Step S21, determining the structural stability index of the regional water resources supply and demand system, wherein the selected index includes evaluating the structural stability of the regional water resources supply and demand system from the perspectives of the natural structure and social structure of the regional water resources supply and demand system;

[0033] Among them, the structure of the regional water resources supply and demand system refers to the relatively stable organizational form or distribution relationship of the elements within the system. The system connects the elements through a certain structure;

[0034] Step S22, determining functional improvement indicators, the selected indicators evaluate the functional improvement of the regional water resources supply and demand system from the perspectives of production capacity, life security and production efficiency of the regional water resources supply and demand system;

[0035] Among them, the function of the system is manifested in the system input, output, and the ability to convert input into output, that is, the system's ability to respond to input;

[0036] Step S23, determining the recoverable index of the operation mechanism, and the selected index evaluates the recoverability of the operation mechanism of the regional water resources supply and demand system from the perspectives of the feedback mechanism of the natural water resources subsystem, the feedback mechanism of the social subsystem and the coupling mechanism between the two subsystems of the regional water resources supply and demand system;

[0037] Among them, the recoverability of the system refers to the ability of the system to restore its structure and function through natural and artificial regulation after being subjected to external pressure or interference;

[0038] Step S3, determining the evaluation criteria of the drought resilience evaluation index of the regional water resources supply and demand system selected in the above step in combination with the actual situation of the study area;

[0039] Step S4, using principal component analysis to optimize the screening indicators;

[0040] Step S5, using a combination of analytic hierarchy process and entropy method to determine the comprehensive weight of the evaluation index after optimization and screening;

[0041] Preferably, the comprehensive weight of the evaluation index after optimization and screening is determined by combining the analytic hierarchy process and the entropy method. The weights of the evaluation index after optimization and screening can be determined by the analytic hierarchy process and the entropy method respectively, and then the two are weighted averaged. Alternatively, the weight obtained by the analytic hierarchy process can be corrected by the weight obtained by the entropy method.

[0042] Step S6, based on the comprehensive weights of the evaluation indicators after optimization and screening, the comprehensive resilience index of the regional water resources supply and demand system is calculated using the fuzzy comprehensive evaluation method to evaluate the drought resilience of the regional water resources supply and demand system.

[0043] Preferably, the structural stability index includes energy self-sufficiency rate, surface water resource change rate, total auxiliary energy value ratio, water resource development and utilization rate, and water resource energy value contribution rate. Among them, energy self-sufficiency rate, surface water resource change rate and total auxiliary energy value ratio are used as indicators for evaluating the natural structural stability of the water resource supply and demand system. Water resource development and utilization rate and water resource energy value contribution rate are used to represent the indicators of social structural stability of the water resource supply and demand system.

[0044] Preferably, the functional improvement index includes water resource energy value output density, water resource net energy value output rate, per capita water resource energy value utilization, water resource life security function ratio, water resource social stability function ratio, water resource employment security function ratio, water resource pension security function ratio, agricultural output energy value ratio, industrial output energy value ratio. Among them, water resource energy value output density, water resource net energy value output rate and electric power energy value ratio are used as indicators reflecting the production capacity of the system water resource supply and demand system. Per capita water resource energy value utilization, basic life security function ratio, social stability function ratio, employment security function ratio and pension security function ratio are selected to reflect the life security capacity of the system water resource supply and demand system. Production benefits are mainly reflected in agricultural and industrial production. Therefore, the agricultural output energy value ratio and industrial output energy value ratio are selected as two indicators.

[0045] Preferably, the restorable indicators of the operation mechanism include water body self-purification capacity, population density, environmental load rate, drought affected area ratio, and energy value sustainability index. Among them, water body self-purification capacity is selected as an indicator reflecting the self-recovery characteristics of the system. Population density is selected as an indicator reflecting the characteristics of artificial regulation. Environmental load rate, drought affected area ratio and system energy value sustainability index are selected as indicators reflecting the characteristics of the system coupling mechanism.

[0046] The drought resilience evaluation index system of the water resources supply and demand system in the above region and the calculation method of each index are shown in Table 1, and the meaning of the parameters are shown in Table 2.

[0047] Table 1 Preliminary resilience evaluation index system for regional water resources supply and demand system

[0048]

[0049]

[0050] Table 2 Parameter meaning

[0051]

[0052]

[0053] The comprehensive resilience index of the regional water resources supply and demand system is calculated by using the fuzzy comprehensive evaluation method on the basis of determining the comprehensive weight of the evaluation indicators after optimization and screening, and the drought resilience of the regional water resources supply and demand system is evaluated. The specific implementation method is as follows:

[0054] Assume that the water resources supply and demand system is u, and use the known multiple resilience levels h (h = 1, 2, ..., c), where c is the number of level divisions, which can be 3, and multiple evaluation indicators x i (i=1,2,…,m) construct the index standard interval matrix:

[0055]

[0056] where a ih 、b ih are the thresholds of the standard value interval of the index i of level h. If the index is the larger the better, the second row of the matrix is ​​used for construction. In this case, a ih >b ih ,h=2,3,…,(c-1), when x i >a i2 When the membership degree μ i1 (u)=1, and substitute this value into the second row and first column of the matrix. The larger the value, the closer the position is. i2 <x i i2 , substitute the value into the corresponding position of the second row of the matrix, and so on. i i(c-1) When the membership degree μ ic (u) = 1. If the indicator is the smaller the better, then use the first row of the matrix to construct it. In this case, a ih <b ih ,h=2,3,…,(c-1), when x i i2 When the membership degree μ i1 (u)=1, and substitute the value into the first row and first column of the matrix. The smaller the value, the closer the position is to the front. i1 <x i i1 , substitute the value into the corresponding position of the first row of the matrix, and so on. i >b​​​​i(c-1) , membership degree μ ic (u)=1. make Then the standard interval matrix is:

[0057]

[0058] According to the physical concept analysis, the standard value matrix Z of the comprehensive resilience evaluation index of the water resources supply and demand system is the index eigenvalue matrix of the index i at level h with a relative membership degree equal to 1. Level h and (h+1) constitute opposing fuzzy attributes. According to the law of unity of opposites, we have

[0059] μ ih (u)+μ i(h+1) (u)=1 (3)

[0060] Among them, μ ih (u) and μ i(h+1) (u) are the relative membership of indicator i to levels h and h+1 in the evaluation index system of water resources supply and demand system u.

[0061] Let the eigenvalue γ of index i be i The standard value interval [z ih , z i(h+1) ], then γ i The relative membership to level h is:

[0062]

[0063] Let point P be the position of index i on the axis of unity of opposites, and draw a continuum diagram of the law of unity of opposites. i With P k and P l The multi-index generalized weight distance between the two ends is

[0064]

[0065]

[0066] Among them, α is the distance parameter, and this study takes the Euclidean distance α=2.

[0067] If the comprehensive relative membership of the multi-index of the water resources supply and demand system u to level h is G h (u) indicates that

[0068]

[0069] In the formula, β is the optimization criterion parameter. In this study, β = 1 is the least square, and β = 2 is the least square optimization criterion. This satisfies the law of unity of opposites and is used to calculate the relative membership of the water resources supply and demand system u to the level h. This study considers that the water resources supply and demand system is a nonlinear system. Therefore, α = 2, β = 1, that is, the Euclidean distance, is used.

[0070]

[0071] By G h (u) constitutes the comprehensive membership matrix H(u), then the eigenvalue of level h is:

[0072]

[0073] Where τ(u) is the normalized vector of the comprehensive relative membership of u to level h.

[0074] The comprehensive relative membership of the water resources supply and demand system u to the resilience level h is defined as the comprehensive resilience index (CRI) of the water resources supply and demand system:

[0075]

[0076] The CRI ranges from 0 to 1. The larger the CRI, the better the comprehensive resilience of the water resources supply and demand system; the smaller the CRI, the worse the comprehensive resilience of the water resources supply and demand system.

[0077] The following is a specific application example of the above solution:

[0078] Chuxiong Yi Autonomous Prefecture is located in the north-central part of Yunnan Province and is an important grain production base in the province. The prefecture covers an area of ​​28,438.41 km 2 , divided into 10 administrative regions, namely Chuxiong City, Lufeng City, Shuangbai County, Mouding County, Nanhua County, Yao'an County, Dayao County, Yongren County, Yuanmou County and Wuding County. From the analysis of disasters in the past three decades, drought is the biggest natural disaster in Chuxiong Prefecture, with an average annual drought area of ​​321,000 mu, accounting for 7.3% of the total cultivated land area of ​​the prefecture. In addition, Yunnan Province suffered three consecutive years of drought from 2010 to 2012, especially in 2010, when it suffered a 100-year-long extreme drought. The wide range, long duration, deep degree and great losses of the drought are rare in the history of Yunnan Province. Among them, Chuxiong City, Chuxiong Prefecture is particularly serious, with more than 200,000 rural people lacking water. In 2010, the sowing area of ​​the early spring was 37 million mu, and the affected area reached 31.48 million mu, accounting for 85% of the sown area. Therefore, this study is representative of Chuxiong Prefecture as the research area.

[0079] The source of Chuxiong Prefecture DEM data is the Geospatial Data Cloud (Geospatial Data Cloud (gscloud.cn)); the source of basic hydrological data is the "Water Resources Bulletin" of Chuxiong Prefecture and Yunnan Province; the source of social and economic data is the "Statistical Yearbook" of Chuxiong Prefecture and Yunnan Province; the source of drought disaster data is the Chuxiong Prefecture Hydrological Bureau.

[0080] According to the calculation method of the above-mentioned preliminary indicators, the comprehensive resilience evaluation index of the water resources supply and demand system in Chuxiong Prefecture was calculated, and the results are shown in Table 3. Considering the correlation between the evaluation index data, the principal component analysis method was used to optimize the comprehensive resilience evaluation index system of the water resources supply and demand system in Chuxiong Prefecture from 2009 to 2012. The KMO and significance were tested (KMO>0.5, P<0.05), and the initial eigenvalue, contribution rate and cumulative contribution rate were obtained. Through the analysis of the factor load matrix, the comprehensive resilience evaluation index system of the water resources supply and demand system in Chuxiong Prefecture was finally selected as shown in Table 4.

[0081] Table 3 Comprehensive resilience evaluation index system and calculation results of Chuxiong Prefecture water resources supply and demand system

[0082]

[0083]

[0084] Table 4 Comprehensive resilience evaluation indicators and weights of Chuxiong Prefecture's water resources supply and demand system

[0085]

[0086] After the evaluation index system and index weights were determined, a system fuzzy comprehensive resilience evaluation model was constructed to calculate the comprehensive resilience index of the water resources supply and demand system in Chuxiong Prefecture from 2009 to 2012. The CRI grade classification standard for the water resources supply and demand system is shown in Table 5. The calculation results are shown in Figure 2As shown. The comprehensive resilience of the water resources supply and demand system in Chuxiong Prefecture is at the "Level II" level, with an average comprehensive resilience index of 0.300; the average CRI of the system structure is 0.564, which is at the "Level I" level, and the average CRI of the system function and operation mechanism are 0.313 and 0.210, which are at the "Level II" and "Level III" levels respectively. Obviously, the resilience level of the system structure is higher than the resilience level of the system function and operation mechanism. The structure of the water resources supply and demand system in Chuxiong Prefecture is relatively stable, which can provide favorable conditions when encountering extreme droughts and help the system resist the damage caused by extreme droughts. The system structure CRI rose briefly in 2010 when the drought was the most severe, and then decreased. This is consistent with the trend of changes in the development and utilization rate of water resources. Under the influence of extreme drought, the development and utilization of water resources first decreased and then increased, indicating that the system structure CRI is greatly affected by the development and utilization rate of water resources. The system function CRI shows a slow increase trend. As the drought develops, the guarantee function of the water resources supply and demand system has significantly improved, indicating that the role of water resources in protecting human life under extreme droughts is becoming more and more obvious. The CRI of the water resources supply and demand system shows a trend of decreasing and then gradually increasing, which is consistent with the changes in the CRI of the system operation mechanism, indicating that the fluctuation of the CRI of the water resources supply and demand system is mainly affected by the system operation mechanism.

[0087] Table 5 CRI classification standards for water resources supply and demand system in Chuxiong Prefecture

[0088]

[0089] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0090] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. Any process or method description in the flowchart or otherwise described herein may be understood to represent a module, fragment or portion of a code including one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes additional implementations, in which the functions may not be performed in the order shown or discussed, including in a substantially simultaneous manner or in the opposite order according to the functions involved, which should be understood by a technician in the technical field to which the embodiments of the present invention belong.

Claims

1. A method for assessing drought resilience of regional water resources supply and demand system based on structure-function-operation mechanism, characterized in that: The steps include: Step S1, establishing a drought resilience evaluation model for the regional water resources supply and demand system, the evaluation model includes a target layer, which serves as the drought resilience layer for the regional water resources supply and demand system; a criterion layer, which includes three characteristic attributes: stable structure, perfect functions, and recoverable operation mechanism; The indicator layer starts from the three characteristic attributes of the water resources supply and demand system and selects indicators that can reflect the stability of the structure, the improvement of functions, and the recoverability of the operation mechanism; Step S2, constructing a drought resilience evaluation index system for the regional water resources supply and demand system: Step S21, determining the structural stability index of the regional water resources supply and demand system, wherein the selected index includes evaluating the structural stability of the regional water resources supply and demand system from the perspectives of the natural structure and social structure of the regional water resources supply and demand system; Step S22, determining functional improvement indicators, the selected indicators evaluate the functional improvement of the regional water resources supply and demand system from the perspectives of production capacity, life security and production efficiency of the regional water resources supply and demand system; Step S23, determining the recoverable index of the operation mechanism, and the selected index evaluates the recoverability of the operation mechanism of the regional water resources supply and demand system from the perspectives of the feedback mechanism of the natural water resources subsystem, the feedback mechanism of the social subsystem and the coupling mechanism between the two subsystems of the regional water resources supply and demand system; Step S3, determining the evaluation criteria of the drought resilience evaluation index of the regional water resources supply and demand system selected in the above step in combination with the actual situation of the study area; Step S4, using principal component analysis to optimize the screening indicators; Step S5, using a combination of analytic hierarchy process and entropy method to determine the comprehensive weight of the evaluation index after optimization and screening; Step S6, based on the comprehensive weights of the evaluation indicators after optimization and screening, the comprehensive resilience index of the regional water resources supply and demand system is calculated using the fuzzy comprehensive evaluation method to evaluate the drought resilience of the regional water resources supply and demand system.

2. The drought resilience assessment method for the regional water resources supply and demand system based on the structure-function-operation mechanism according to claim 1 is characterized by: The structural stability indicators include energy self-sufficiency rate, surface water resource change rate, total auxiliary energy ratio, water resource development and utilization rate, and water resource energy contribution rate.

3. The drought resilience assessment method for the regional water resources supply and demand system based on the structure-function-operation mechanism according to claim 1 is characterized by: The functional improvement indicators include water resources energy output density, water resources net energy output rate, per capita water resources energy utilization, water resources life security function ratio, water resources social stability function ratio, water resources employment security function ratio, water resources pension security function ratio, agricultural output energy ratio, and industrial output energy ratio.

4. The method for evaluating drought resilience of a regional water resources supply and demand system based on a structure-function-operation mechanism according to claim 1, characterized in that: The restorable indicators of the operation mechanism include water self-purification capacity, population density, environmental load rate, drought-affected area ratio, and energy value sustainability index.

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