阅读说明：本技术 一种多类型生物多样性综合评估指标体系的构建方法 (Construction method of multi-type biodiversity comprehensive evaluation index system ) 是由 刘洋 张敏 渠晓东 彭文启 蒋定国 葛金金 解莹 余杨 张海萍 于 2021-08-16 设计创作，主要内容包括：本发明公开一种多类型生物多样性综合评估指标体系的构建方法,其特征在于：它包括如下步骤：步骤1)：构建综合评估指标体系框架；步骤2)：基于生物个体数量、功能性状和系统发育特征,筛选出能够良好反映生物多样性的指标；步骤3)：结合生物群落的实际情况,确定生物多样性综合评估指标体系中各个指标的界定标准,计算出各个生物多样性评估指标的具体数值；步骤4)：利用主成分分析方法计算各指标权重；步骤5)：得到各个单项指标评价值及其权重后,利用叠置指数法计算得到多类型生物多样性综合指数；本发明解决了综合多类型生物多样性定量评估方法缺乏的技术问题,建立系统有效的生物多样性保护策略。(The invention discloses a method for constructing a comprehensive evaluation index system of multi-type biodiversity, which is characterized by comprising the following steps of: it comprises the following steps: step 1): constructing a comprehensive evaluation index system framework; step 2): screening out indexes capable of well reflecting biological diversity based on the biological individual quantity, functional characters and phylogenetic characteristics; step 3): determining the definition standard of each index in a biodiversity comprehensive evaluation index system by combining the actual situation of the biological community, and calculating the specific numerical value of each biodiversity evaluation index; step 4): calculating the weight of each index by using a principal component analysis method; step 5): after obtaining each single index evaluation value and the weight thereof, calculating by using a superposition index method to obtain a multi-type biological diversity comprehensive index; the invention solves the technical problem of lacking of a comprehensive multi-type biodiversity quantitative evaluation method, and establishes a systematic and effective biodiversity protection strategy.)

1. A method for constructing a multi-type biodiversity comprehensive evaluation index system is characterized by comprising the following steps: it comprises the following steps:

step 1): constructing a set of comprehensive evaluation index system framework containing the variety, the functional diversity and the phylogenetic diversity of various types of organisms;

step 2): screening out indexes capable of well reflecting biological diversity based on the biological individual quantity, functional characters and phylogenetic characteristics;

step 3): determining the definition standard of each index in a biodiversity comprehensive evaluation index system by combining the actual situation of the biological community, and calculating the specific numerical value of each biodiversity evaluation index;

step 4): after the original data are standardized by a minimum range standardization method, the weights of all indexes are calculated by a principal component analysis method, and the final weights of all indexes are further calculated by an index weight normalization method;

step 5): and after obtaining the evaluation value and the weight of each single index, calculating by using a superposition index method to obtain the comprehensive index of the multi-type biological diversity.

2. The method according to claim 1, wherein the multi-type biodiversity comprehensive evaluation index system comprises: in the step 1), the quantitative index of the variety of the species selects a richness index, a uniformity index, a fragrance concentration diversity index and an dominance index to comprehensively reflect the variety of the species.

3. The method according to claim 2, wherein the multi-type biodiversity comprehensive evaluation index system comprises:

(1) the richness index calculation formula is as follows:

wherein d is Margalef abundance index; n is the total number of individuals; s is the number of species;

(2) the uniformity index calculation formula is as follows:

wherein J is the Pielouj uniformity index; h' is the Shannon-wiener diversity index; s is the number of species;

(3) the aroma diversity index calculation formula is as follows:

wherein H' is the Shannon-wiener diversity index; ni is the number of individuals of the species in i; n is the total number of individuals;

(4) the dominance index calculation formula is as follows:

wherein D is Simpson dominance index; ni is the number of individuals of the species in i; n is the total number of individuals.

4. The method according to claim 1, wherein the multi-type biodiversity comprehensive evaluation index system comprises: in the step 1), according to the difference of the large benthonic animals in the river ecosystem on the variation response of the hydrological situation, selecting representative functional characters capable of effectively representing the large benthonic animals to resist the environmental fluctuation and calculating various functional diversity indexes, wherein the functional diversity indexes comprise a functional diversity index, a functional uniformity index, a functional diversity index and a quadratic entropy index (Rao's).

5. The method according to claim 4, wherein the multi-type biodiversity comprehensive evaluation index system comprises:

(1) the functional abundance index calculation formula is as follows:

in the formula FR_ciIs the work of the feature c in the community iThe degree of richness can be realized; SF_ciIs the niche occupied by the species within the community; r_cIs the absolute eigenvalue range;

(2) the functional uniformity index calculation formula is as follows:

in the formula P_iIs the relative eigenvalue of species i; s is the number of species;

(3) the function differentiation index calculation formula is as follows:

in the formula FD_ivIs a function differentiation index comprising a plurality of functional characteristics; c_iIs the value of the functional characteristic of item i; a. the_iIs the relative richness of the functional features of item i,is the weighted average of the natural logarithm of the species eigenvalues, N is the number of species in the community;

(4) the quadratic entropy index (Rao's) is calculated by the formula:

in the formula d_ijIs the functional characteristic distance between the i species and the j species in the community; p_iIs the ratio of the number of species i to the total number of species in the community; p_jIs the ratio of the number of species j to the total number of species in the community; s is the total population in the population.

6. The method according to claim 1, wherein the multi-type biodiversity comprehensive evaluation index system comprises: in the step 1), a phylogenetic diversity index is calculated according to the degree of relationship of the large benthonic animals of the river ecosystem in the phylogenetic classification tree, wherein the phylogenetic diversity index comprises a classification diversity index, a classification difference index, an average classification difference index and a classification difference variability index.

7. The method according to claim 6, wherein the multi-type biodiversity comprehensive evaluation index system comprises:

(1) and (3) calculating a classification diversity index:

the classification diversity index is used for calculating the average classification distance between any two species in a phylogenetic classification dendrogram;

in the formula X_iIs the number of the ith species, X_jIs the jth species number; omega_ijIs the path length of the ith and jth species in the classification tree;

(2) and (3) calculating a classification difference index:

the classification difference index is obtained by neglecting the path length between individuals of the same species when calculating the average classification distance between any two species in a phylogenetic classification dendrogram;

in the formula X_iIs the number of the ith species, X_jIs the jth species number; omega_ijIs the path length of the ith and jth species in the classification tree;

(3) calculating the average classification difference index:

the average classification difference index is the path length of the average classification distance between any pair of species in the species directory, and the abundance of the species is not considered;

in the formula of omega_ijIs the path length of the ith and jth species in the classification tree; s is the number of species present in the community;

(4) and (3) calculating a classification difference variability index:

the classification difference variability index is a theoretical average value for calculating the deviation degree of the average classification difference index, and the variability of the path distance between each pair of species is evaluated;

in the formula of omega_ijIs the path length of the ith and jth species in the classification tree; s is the number of species present in the community.

8. The method according to claim 1, wherein the multi-type biodiversity comprehensive evaluation index system comprises: the calculation formula of the minimum range standardization method in the step 4) for standardizing the original species data is as follows:

in the formula X_ijAnd Z_ijThe evaluation indexes are respectively the raw data value and the normalized data value of the ith (i 1,2,.. multidot.m) th point of the evaluation index jth (j 1,2,.. multidot.n), minX_iAnd maxX_iThe minimum data value and the maximum data value of the ith evaluation index are respectively.

9. The method according to claim 1, wherein the multi-type biodiversity comprehensive evaluation index system comprises: the specific process of calculating the weight of each index by the principal component analysis method in the step 4) is as follows:

(1) and a correlation coefficient matrix calculation process:

calculating a corresponding correlation coefficient matrix R by the standardized data matrix, and calculating a characteristic value and a characteristic vector of R;

R＝-(r_ij) p × p (formula 14)

Wherein:

wherein i 1,2, 1.. said., n, j 1,2, 1.. said., p, R have a characteristic value λ_iThe eigenvector is lambda_i(i＝1，2，......，p)；

(2) And (3) calculating a principal component model:

acquiring principal components according to the accumulated contribution rate, enabling the characteristic value of the principal components to be larger than 1, selecting k principal components, and establishing a principal component model;

1 st principal component F₁＝a₁₁Z₁+a₂₁Z₂+a₃₁Z₃+…+a_p1Z_p(formula 16)

2 nd principal component F₂＝a₁₂Z₂+a₂₂Z₂+a₃₂Z₃+…+a_p2Z_p(formula 17)

The k-th principal component F_k＝a_1kZ₂+a_2kZ₂+a_3kZ₃+…+a_pkZ_p(formula 18)

In the formula a_ijThe factor score coefficient of the factor i in the jth principal component and the contribution rate of the ith factor to the jth principal component, which is the contribution rate E of the variance corresponding to the principal component, are described_jThe combination of (a) and (b) is the weight value of the ith factor;

in the formula a_ijThe factor score coefficient, E, of the factor i in the jth principal component is described_jIs the contribution of the jth principal component variance, W_iThe calculated index weight value is obtained;

(3) the normalization calculation process of the index weight comprises the following steps:

the index weight needs to be normalized on the basis of an index coefficient in the comprehensive model, and the sum of the weights of all indexes is ensured to be 1;

in the formula W_i ⁰Is the final weight value of the normalized index, W_iThe weight values of the indexes are not normalized.

10. The method according to claim 1, wherein the multi-type biodiversity comprehensive evaluation index system comprises: the comprehensive index of the biodiversity in the step 5) is as follows:

wherein HB is the comprehensive index of biological diversity, W_i ⁰Normalizing the weight value for the ith index, Z_iThe evaluation value normalized for the i-th index.

Technical Field

The invention relates to the technical field of biodiversity protection, in particular to a method for constructing a multi-type biodiversity comprehensive evaluation index system.

Background

Biodiversity refers to the integration of the ecological complex formed by organisms and their environment in the ecosystem and the various ecological processes associated therewith. From the perspective of the number, functions and genetic evolutionary relationships of organisms, biodiversity is divided into multiple levels of Species diversity (specificity diversity), Functional diversity (Functional diversity) and Phylogenetic diversity (Phylogenetic diversity). Species diversity is a condition that reflects species diversity on the species level based on species type, number, abundance, and uniformity. Functional diversity at the level of functional traits, the status of functional diversity is reflected based on the differential characteristics of functional traits among species. Phylogenetic diversity at the level of species evolutionary relationships reflects the diversity of species genetic evolutionary relationships based on the differential characteristics of membership between biological species.

From the viewpoint of species diversity, it is currently the most widely used method to evaluate the biodiversity status with the emphasis on the information on the number and relative abundance of species. And in the calculation process of the species diversity, each species in the community is regarded as equivalent, and the difference of the functional character characteristics and the genetic evolutionary relationship distance among the species is ignored. The absence of this information leads to a certain one-sidedness in the assessment of biodiversity at the level of species diversity. The comprehensive evaluation of the biodiversity system is the key of biodiversity protection in the ecosystem by considering the individual quantity, the functional character characteristics and the genetic evolutionary relationship difference characteristics of organisms.

Therefore, how to integrate the characteristics of multiple types of diversity and establish a method for comprehensively evaluating the biodiversity of a multi-angle system, and further establish an effective biodiversity protection strategy of the system becomes a technical problem to be solved urgently.

Disclosure of Invention

The invention aims to overcome the defects and provide a method for constructing a comprehensive evaluation index system of the multi-type biodiversity so as to solve the technical problem that a comprehensive quantitative evaluation method of the multi-type biodiversity is lacked and establish an effective biodiversity protection strategy of the system.

In order to solve the technical problems, the invention adopts the technical scheme that: a method for constructing a multi-type biodiversity comprehensive evaluation index system comprises the following steps:

step 1): constructing a set of comprehensive evaluation index system framework containing the variety, the functional diversity and the phylogenetic diversity of various types of organisms;

step 2): screening out indexes capable of well reflecting biological diversity based on the biological individual quantity, functional characters and phylogenetic characteristics;

step 3): determining the definition standard of each index in a biodiversity comprehensive evaluation index system by combining the actual situation of the biological community, and calculating the specific numerical value of each biodiversity evaluation index;

step 4): after the original data are standardized by a minimum range standardization method, the weights of all indexes are calculated by a principal component analysis method, and the final weights of all indexes are further calculated by an index weight normalization method;

step 5): and after obtaining the evaluation value and the weight of each single index, calculating by using a superposition index method to obtain the comprehensive index of the multi-type biological diversity.

Preferably, in the step 1), the quantitative index of the variety of the species selects the abundance index, the evenness index, the fragrance concentration diversity index and the dominance index to comprehensively reflect the variety of the species.

Preferably, (1) the abundance index calculation formula is:

wherein d is Margalef abundance index; n is the total number of individuals; s is the number of species;

(2) the uniformity index calculation formula is as follows:

wherein J is the Pielouj uniformity index; h' is the Shannon-wiener diversity index; s is the number of species;

(3) the aroma diversity index calculation formula is as follows:

wherein H' is the Shannon-wiener diversity index; ni is the number of individuals of the species in i; n is the total number of individuals;

(4) the dominance index calculation formula is as follows:

wherein D is Simpson dominance index; ni is the number of individuals of the species in i; n is the total number of individuals.

Preferably, in the step 1), according to the difference of the large benthonic animals in the river ecosystem to the variation response of the hydrological situation, representative functional traits capable of effectively representing the resistance of the large benthonic animals to environmental fluctuation are selected to calculate each functional diversity index, and the functional diversity index comprises a functional diversity index, a functional uniformity index, a functional diversity index and a quadratic entropy index (Rao's).

Preferably, (1) the functional abundance index calculation formula is:

in the formula FR_ciIs the functional abundance of the feature c in the community i; SF_ciIs the niche occupied by the species within the community; r_cIs the absolute eigenvalue range;

(2) the functional uniformity index calculation formula is as follows:

in the formula P_iIs the relative eigenvalue of species i; s is the number of species;

(3) the function differentiation index calculation formula is as follows:

in the formula FD_ivIs a function differentiation index comprising a plurality of functional characteristics; c_iIs the value of the functional characteristic of item i; a. the_iIs the relative richness of the functional features of item i,is the weighted average of the natural logarithm of the species eigenvalues, N is the number of species in the community;

(4) the quadratic entropy index (Rao's) is calculated by the formula:

in the formula d_ijIs the functional characteristic distance between the i species and the j species in the community; p_iIs the ratio of the number of species i to the total number of species in the community; p_jIs the ratio of the number of species j to the total number of species in the community; s is the total population in the population.

Preferably, in the step 1), a phylogenetic diversity index is calculated according to the degree of relationship of the large benthonic animals of the river ecosystem in the phylogenetic classification tree, wherein the phylogenetic diversity index includes a classification diversity index, a classification difference index, an average classification difference index and a classification difference variability index.

Preferably, (1) the classification diversity index calculation process:

the classification diversity index is used for calculating the average classification distance between any two species in a phylogenetic classification dendrogram;

in the formula X_iIs the number of the ith species, X_jIs the jth species number; omega_ijIs the path length of the ith and jth species in the classification tree;

(2) and (3) calculating a classification difference index:

the classification difference index is obtained by neglecting the path length between individuals of the same species when calculating the average classification distance between any two species in a phylogenetic classification dendrogram;

in the formula X_iIs the number of the ith species, X_jIs the jth species number; omega_ijIs the path length of the ith and jth species in the classification tree;

(3) calculating the average classification difference index:

the average classification difference index is the path length of the average classification distance between any pair of species in the species directory, and the abundance of the species is not considered;

in the formula of omega_ijIs the path length of the ith and jth species in the classification tree; s is the number of species present in the community;

(4) and (3) calculating a classification difference variability index:

the classification difference variability index is a theoretical average value for calculating the deviation degree of the average classification difference index, and the variability of the path distance between each pair of species is evaluated;

in the formula of omega_ijIs the path length of the ith and jth species in the classification tree; s is the number of species present in the community.

Preferably, the minimum range normalization method in step 4) normalizes the original species data by the calculation formula:

in the formula X_ijAnd Z_ijThe data values are the raw data value and normalized data value of the ith (i is 1,2, … …, m) th evaluation index jth (j is 1,2, … …, n), minX_iAnd maxX_iThe minimum data value and the maximum data value of the ith evaluation index are respectively.

Preferably, the specific process of calculating the weight of each index by the principal component analysis method in step 4) is as follows:

(1) and a correlation coefficient matrix calculation process:

calculating a corresponding correlation coefficient matrix R by the standardized data matrix, and calculating a characteristic value and a characteristic vector of R;

R＝-(r_ij) p × p (formula 14)

Wherein:

wherein i 1,2, 1.. said., n, j 1,2, 1.. said., p, R have a characteristic value λ_iThe eigenvector is lambda_i(i＝1，2，......，p)；

(2) And (3) calculating a principal component model:

acquiring principal components according to the accumulated contribution rate, enabling the characteristic value of the principal components to be larger than 1, selecting k principal components, and establishing a principal component model;

1 st principal component F₁＝a₁₁Z₁+a₂₁Z₂+a₃₁Z₃+…+a_p1Z_p(formula 16)

2 nd principal component F₂＝a₁₂2₂+a₂₂Z₂+a₃₂Z₃+…+a_p2Z_p(formula 17)

The k-th principal component F_k＝a_1kZ₂+a_2kZ₂+a_3kZ₃+…+a_pkZ_p(formula 18)

In the formula a_ijThe factor score coefficient of the factor i in the jth principal component and the contribution rate of the ith factor to the jth principal component, which is the contribution rate E of the variance corresponding to the principal component, are described_jThe combination of (a) and (b) is the weight value of the ith factor;

in the formula a_ijThe factor score coefficient, E, of the factor i in the jth principal component is described_jIs the contribution of the jth principal component variance, W_iThe calculated index weight value is obtained;

(3) the normalization calculation process of the index weight comprises the following steps:

the index weight needs to be normalized on the basis of an index coefficient in the comprehensive model, and the sum of the weights of all indexes is ensured to be 1;

in the formula W_i ⁰Is the final weight value of the normalized index, W_iThe weight values of the indexes are not normalized.

Preferably, the comprehensive index of biodiversity in step 5) is:

wherein HB is the comprehensive index of biological diversity, W_i ⁰Normalizing the weight value for the ith index, Z_iThe evaluation value normalized for the i-th index.

The invention has the beneficial effects that:

a comprehensive biodiversity quantitative evaluation system for maintaining the stability of an ecosystem based on biodiversity is constructed, and the diversity is integrated on the characteristics of species diversity, functional diversity and phylogenetic diversity.

And secondly, the evaluation result is the comprehensive evaluation of the quantity, the function and the evolution characteristics of the biological community in an ecological system, and the system reflects the diversity of the biological community in quantity and classification and also reflects the diversity of the biological function and evolution development.

And thirdly, the index system is not specific to a certain type of ecosystem and has certain universality.

And fourthly, based on a biological mechanism for maintaining the stability of the ecological system by the biodiversity, selecting an appropriate diversity index by integrating the number of biological individuals, functional characters and phylogenetic characteristics, and systematically quantifying the current situation of biodiversity by establishing a multi-type biodiversity comprehensive index calculation method and a comprehensive evaluation method, thereby establishing an effective biodiversity protection strategy and more accurately protecting the biodiversity.

Drawings

FIG. 1 is a graph of the results of the comprehensive index of biodiversity according to one embodiment of the present invention;

FIG. 2 is a graph of seasonal variation of a composite index of biodiversity according to one embodiment of the present invention;

FIG. 3 is a diagram of seasonal variations of various types of diversity indices selected in accordance with an embodiment of the present invention.

Detailed Description

The invention is described in further detail below with reference to the figures and specific embodiments.

A method for constructing a multi-type biodiversity comprehensive evaluation index system comprises the following steps:

step 1): constructing a set of comprehensive evaluation index system framework containing the variety, the functional diversity and the phylogenetic diversity of various types of organisms;

step 2): screening out indexes capable of well reflecting biological diversity based on the biological individual quantity, functional characters and phylogenetic characteristics;

step 3): determining the definition standard of each index in a biodiversity comprehensive evaluation index system by combining the actual situation of the biological community, and calculating the specific numerical value of each biodiversity evaluation index;

step 4): after the original data are standardized by a minimum range standardization method, the weights of all indexes are calculated by a principal component analysis method, and the final weights of all indexes are further calculated by an index weight normalization method;

step 5): and after obtaining the evaluation value and the weight of each single index, calculating by using a superposition index method to obtain the comprehensive index of the multi-type biological diversity.

Preferably, in the step 1), the quantitative index of the variety of the species selects the abundance index, the evenness index, the fragrance concentration diversity index and the dominance index to comprehensively reflect the variety of the species.

Preferably, (1) the abundance index calculation formula is:

wherein d is Margalef abundance index; n is the total number of individuals; s is the number of species;

(2) the uniformity index calculation formula is as follows:

wherein J is the Pielouj uniformity index; h' is the Shannon-wiener diversity index; s is the number of species;

(3) the aroma diversity index calculation formula is as follows:

wherein H' is the Shannon-wiener diversity index; ni is the number of individuals of the species in i; n is the total number of individuals;

(4) the dominance index calculation formula is as follows:

wherein D is Simpson dominance index; ni is the number of individuals of the species in i; n is the total number of individuals.

Preferably, in the step 1), according to the difference of the large benthonic animals in the river ecosystem to the variation response of the hydrological situation, representative functional traits capable of effectively representing the resistance of the large benthonic animals to environmental fluctuation are selected to calculate each functional diversity index, and the functional diversity index comprises a functional diversity index, a functional uniformity index, a functional diversity index and a quadratic entropy index (Rao's).

Preferably, (1) the functional abundance index calculation formula is:

in the formula FR_ciIs the work of the feature c in the community iThe degree of richness can be realized; SF_ciIs the niche occupied by the species within the community; r_cIs the absolute eigenvalue range;

(2) the functional uniformity index calculation formula is as follows:

in the formula P_iIs the relative eigenvalue of species i; s is the number of species;

(3) the function differentiation index calculation formula is as follows:

in the formula FD_ivIs a function differentiation index comprising a plurality of functional characteristics; c_iIs the value of the functional characteristic of item i; a. the_iIs the relative richness of the functional features of item i,is the weighted average of the natural logarithm of the species eigenvalues, N is the number of species in the community;

(4) the quadratic entropy index (Rao's) is calculated by the formula:

in the formula d_ijIs the functional characteristic distance between the i species and the j species in the community; p_iIs the ratio of the number of species i to the total number of species in the community; p_jIs the ratio of the number of species j to the total number of species in the community; s is the total population in the population.

Preferably, in the step 1), a phylogenetic diversity index is calculated according to the degree of relationship of the large benthonic animals of the river ecosystem in the phylogenetic classification tree, wherein the phylogenetic diversity index includes a classification diversity index, a classification difference index, an average classification difference index and a classification difference variability index.

Preferably, (1) the classification diversity index calculation process:

the classification diversity index is used for calculating the average classification distance between any two species in a phylogenetic classification dendrogram;

in the formula X_iIs the number of the ith species, X_jIs the jth species number; omega_ijIs the path length of the ith and jth species in the classification tree;

(2) and (3) calculating a classification difference index:

the classification difference index is obtained by neglecting the path length between individuals of the same species when calculating the average classification distance between any two species in a phylogenetic classification dendrogram;

in the formula X_iIs the number of the ith species, X_jIs the jth species number; omega_ijIs the path length of the ith and jth species in the classification tree;

(3) calculating the average classification difference index:

the average classification difference index is the path length of the average classification distance between any pair of species in the species directory, and the abundance of the species is not considered;

in the formula of omega_ijIs the path length of the ith and jth species in the classification tree; s is the number of species present in the community;

(4) and (3) calculating a classification difference variability index:

the classification difference variability index is a theoretical average value for calculating the deviation degree of the average classification difference index, and the variability of the path distance between each pair of species is evaluated;

in the formula of omega_ijIs the path length of the ith and jth species in the classification tree; s is the number of species present in the community.

Preferably, the raw data is normalized to eliminate the differences of the indexes in the attributes and magnitude. The standardization processing mainly solves the problem of summation of different attribute data, so that different attribute index variables play the same direction in the comprehensive evaluation, the dimensional influence of the variables is eliminated, and the indexes after standardization generate negative values to be not beneficial to the subsequent operation; the calculation formula of the minimum range standardization method in the step 4) for standardizing the original species data is as follows:

in the formula X_ijAnd Z_ijThe data values are the raw data value and normalized data value of the ith (i is 1,2, … …, m) th evaluation index jth (j is 1,2, … …, n), minX_iAnd maxX_iThe minimum data value and the maximum data value of the ith evaluation index are respectively.

In the embodiment of the invention, based on the data of large benthonic animals in red water rivers (ecological rivers without gate dams) and black water rivers (gate dam regulated rivers) in 2019 and in months 4 and 9, a comprehensive evaluation index system frame of the multi-type biological diversity of a river ecosystem under different hydrologic situation variations is constructed, and is shown in table 1.

TABLE 1 comprehensive assessment index System and description of biodiversity

Preferably, the specific process of calculating the weight of each index by the principal component analysis method in step 4) is as follows:

(1) and a correlation coefficient matrix calculation process:

calculating a corresponding correlation coefficient matrix R by the standardized data matrix, and calculating a characteristic value and a characteristic vector of R;

R＝-(r_ij) p × p (formula 14)

Wherein:

wherein i is 1,2, … …, n, j is 1,2, … …, p, R has a characteristic value of lambda_iThe eigenvector is lambda_i(i＝1,2,……,p)；

(2) And (3) calculating a principal component model:

acquiring principal components according to the accumulated contribution rate, enabling the characteristic value of the principal components to be larger than 1, selecting k principal components, and establishing a principal component model;

1 st principal component F₁＝a₁₁Z₁+a₂₁Z₂+a₃₁Z₃+…+a_p1Z_p(formula 16)

2 nd principal component F₂＝a₁₂2₂+a₂₂Z₂+a₃₂Z₃+…+a_p2Z_p(formula 17)

The k-th principal component F_k＝a_1kZ₂+a_2kZ₂+a_3kZ₃+…+a_pkZ_p(formula 18)

In the formula a_ijThe factor score coefficient of the factor i in the jth principal component and the contribution rate of the ith factor to the jth principal component, which is the contribution rate E of the variance corresponding to the principal component, are described_jThe combination of (a) and (b) is the weight value of the ith factor;

in the formula a_ijThe factor score coefficient, E, of the factor i in the jth principal component is described_jIs the jth principal componentContribution of variance, W_iThe calculated index weight value is obtained;

(3) the normalization calculation process of the index weight comprises the following steps:

the index weight needs to be normalized on the basis of an index coefficient in the comprehensive model, and the sum of the weights of all indexes is ensured to be 1;

in the formula W_i ⁰Is the final weight value of the normalized index, W_iThe weight values of the indexes are not normalized.

The calculation results of the index weights in the embodiment of the invention are shown in table 2:

TABLE 2 index weight value calculation results

Preferably, the comprehensive index of biodiversity in step 5) is:

wherein HB is the comprehensive index of biological diversity, W_i ⁰Normalizing the weight value for the ith index, Z_iThe evaluation value normalized for the i-th index.

Comprehensive evaluation results of biodiversity:

the embodiment of the invention finally obtains the biodiversity status of the red river (ecological river without gate dam, remarkable hydrological situation variation and frequent flood in summer) and the black river (river regulated by gate dam and small hydrological situation) in 2019 in 4 months and 9 months (figure 1). Through quantitative evaluation of a system, under the influence of remarkable variation of hydrologic conditions, the average value of the comprehensive index of biodiversity of the Chishuihe river in month 4 is 0.550, the comprehensive index of the month 9 is 0.466, and remarkable seasonal variation is presented. In a black river with a relatively stable hydrological situation under the control of the gate dam, the comprehensive diversity index of 4 months is 0.483, 9 months is 0.482, and the seasonal change is not significant (figure 2). Compared with the comprehensive evaluation index of biodiversity, the index of species diversity shows obvious seasonal variation in both red and black rivers (fig. 3), and the influence of normal seasonal fluctuation and abnormal disturbance (natural disturbance such as flood, fire and the like, artificial disturbance such as water environment pollution and the like) of biodiversity on the diversity cannot be effectively distinguished by the species diversity.

The comprehensive biodiversity evaluation index is integrated with the characteristics of the individual number, the functional characters, the phylogenetic evolution genetic relationship characteristics and the like of the large benthonic animal species, one-sided evaluation of the individual number of the species to the biodiversity is avoided, the influence of normal seasonal fluctuation and abnormal interference on the biodiversity can be effectively distinguished from the aspects of the functional characteristics, the genetic evolution relationship and the like, and the current situation of the biodiversity in a natural ecological system can be more comprehensively and effectively evaluated.

It is to be understood that in the above-mentioned examples, the selection of the individual indices in the evaluation of the diversity of the large benthonic animals according to the river ecosystem was described and shown, and the present invention is not limited to the described and shown river ecosystem, large benthonic animals and representative diversity indices. The invention has universality characteristic, is suitable for lake ecosystems, forest ecosystems, marine ecosystems and the like, and is also suitable for biological communities of phytoplankton, zooplankton, fish and the like. After the spirit of the invention is comprehended, the skilled person can select a proper diversity index according to the type of the selected ecosystem and the biological characteristics of the research object, construct a proper diversity comprehensive evaluation index system according to the biodiversity comprehensive evaluation index system framework of the invention, and finish the comprehensive evaluation of biodiversity.