CN105975787A - Urban river ecological multi-level evaluation method based on analytic hierarchy method - Google Patents

Abstract

The invention provides an urban river ecological multi-level evaluation method based on an analytic hierarchy method and belongs to the field of water ecology. The method is a method for assessing a modern Urban River Eco-index quantitatively. A set of multi-level assessment system containing first-level indexes and second-level indexes is established, a base weight of the assessment indexes is determined through the analytic hierarchy method, the base weight is corrected through a Delphi method so that a final weight vector can be obtained, finally, the index scores and weights of the indexes are weighted to obtain scores, and urban river ecological quantitative evaluation analysis is carried out according to the acquired final scores for urban river ecological evaluation. Based on data tracking on urban ecological river construction, the complete urban ecological river assessment system is established, bases can be provided for difference analysis of the current situation and the objective of the urban river ecological construction, the construction direction of the next step is cleared, and an effective technical management tool is provided for effect evaluation of the urban river ecological construction.

Description

A kind of city inland river ecological multi-layer level evaluating method based on analytic hierarchy process (AHP)

Technical field

The present invention relates to water ecology evaluation and test field, particularly relate to a kind of city inland river ecology based on analytic hierarchy process (AHP) many Level evaluating method.

Background technology

City inland river be city provide water supply, shipping, receive dirt etc. multiple resources and Ecosystem Service, be that city is aquatic The important carrier of state environment.But in recent years, developing rapidly and urban population rapid growth, in city due to urban economy The pollution in river is increasingly severe, and the multiple resources in inland river is the most progressively lost with Ecosystem Service.China's city inland river at present Treatment status mostly the most still based on flood control, ignore the ecological functions in inland river, often result in regulation effect unsatisfactory, water body The problem that pollution cannot thoroughly solve.Administering of city inland river basic is drained off floodwater in addition to demand except meeting, and also should try one's best Keep the physical feature in inland river, the space of existence is provided for all kinds of aquatiles.In recent years, the ecological management of city inland river is subject to Paying close attention to, Jiangsu, Shanghai, Foochow etc. are regional has risen the upsurge of inland river ecological construction one after another and has carried out Preliminary Practice, the most also There is a large amount of scholar that the ecological evaluation problem of city inland river is studied, but be mostly in exploration and starting stage, for city The ecological management pattern in inland river, city and the ecological evaluation in inland river not yet form complete evaluation system, especially quantizing process not Know, this effect that inland river is administered can not get objective, comprehensively understand, and after administering, the management in inland river also lacks science Guidance.Therefore, in order to ensure the smooth enforcement of city inland river ecological construction, the development of inland river, future city ecological construction is specified Direction, corrects problem present in building in time, and the city inland river ecological assessment system of Erecting and improving is particularly important.

Summary of the invention

The present invention solves above-mentioned technical problem, be to provide a kind of city inland river ecological multi-layer based on analytic hierarchy process (AHP) Level evaluating method, comprises the following steps:

Step 1, sets up index system: ecological characteristic based on city inland river and construction characteristics, and according to city inland river In ecological key element set up multi-layer city inland river ecological assessment index system, described ecological key element is divided into first class index and Two-level index；

Step 2, data process: ecological key elements different in city inland river carries out the data inputting of nondimensionalization, and adopts Determine the basic weight of each ecological key element with analytic hierarchy process (AHP), use Delphi method to be modified basis weight obtaining final Weight vectors；

Step 3, determines the ecological index of city inland river: each for city inland river ecological key element correspondence different brackets is converted into phase The mark answered, by mark and its Weight of each ecological key element, obtains city inland river ecological index UREI；

Step 4, evaluation and test: the city inland river ecological index UREI according to obtaining carries out the evaluation and test that city inland river is ecological.

Further, described first class index include buffer strip first class index A1, city inland river shore protection first class index A2 and City inland river water body first class index A3；Each first class index all includes two-level index, described city inland river buffer strip first class index bag Include vegetation type two-level index B11, buffer strip width two-level index B12, community continuum two-level index B13, vegetation structure complete Whole property two-level index B14, vegetation coverage two-level index B15, described city inland river shore protection first class index includes the shore protection gradient two Level index B21, shore protection hydrophilic two-level index B22, shore protection type two-level index B23, shore protection stability two-level index B24, protect Bank view two-level index B25, vegetation coverage two-level index B26, described city inland river river course first class index includes water conservancy merit Energy two-level index B31, river course channelization degree two-level index B32, river course flexibility two-level index B33, streamflow regime two grades refer to Mark B34, riverbed silt particle composition two-level index B35, riverbed matrix type two-level index B36, Eutrophic Extent two-level index B37, water quality two-level index B38, water plant seriality two-level index B39, water plant structural intergrity two-level index B310, Indicating organism for water pollution two-level index B311, Fish two-level index B312.

Further, in described step 4, when UREI >=3.2 timesharing, illustrate that this city inland river is ecological very well；When 2.4≤ UREI < when 3.2, illustrates that this city inland river is ecological well；When 1.6≤UREI < when 2.4, illustrates this city inland river ecological As；When 0.8≤UREI < when 1.6, illustrates that this city inland river is ecological poor；When 0≤UREI < 0.8 timesharing, in this city is described River ecological functions almost completely lose.

Further, in described step 3, the mark that each ecological key element correspondence different brackets is converted is 0～4 point, mark The highest show that situation is the best, on the contrary the poorest.

Further, wherein river course refers to both sides, inland river mean annual water level riverbed included below, riverbed and water body Part, shore protection refers to slope and the bank guardrail part of more than inland river mean annual water level, buffer strip refer to shore protection guardrail with Outward, there is no the land-based area area of other land used attribute.

Advantages of the present invention: the invention provides a set of city inland river based on analytic hierarchy process (AHP) quantization ecological multi-layer level and comment Survey method, this evaluating method can be quickly obtained the ecological of city inland river, and be the ecological construction of city inland river, evaluation And management provides direction and guidance.

Accompanying drawing explanation

The present invention is further illustrated the most in conjunction with the embodiments.

Fig. 1 is the schematic flow sheet of the present invention；

Fig. 2 is the schematic diagram of multi-layer city inland river ecological assessment index system；

Fig. 3 is that city inland river buffer strip, shore protection and region, river course divide schematic diagram.

Detailed description of the invention

Refer to Fig. 1, be that a kind of based on analytic hierarchy process (AHP) the city inland river as highly preferred embodiment of the present invention is ecological Multi-layer evaluating method, comprises the following steps:

Step 1, sets up index system: ecological characteristic based on city inland river and construction characteristics, and according to city inland river In ecological key element set up multi-layer city inland river ecological assessment index system, described ecological key element is divided into first class index and Two-level index.As in figure 2 it is shown, described first class index include buffer strip first class index A1, city inland river shore protection first class index A2 with And city inland river water body first class index A3；Each first class index all includes two-level index, described city inland river buffer strip first class index Including vegetation type two-level index B11, buffer strip width two-level index B12, community continuum two-level index B13, vegetation structure Integrity two-level index B14, vegetation coverage two-level index B15, described city inland river shore protection first class index includes the shore protection gradient Two-level index B21, shore protection hydrophilic two-level index B22, shore protection type two-level index B23, shore protection stability two-level index B24, Shore protection view two-level index B25, vegetation coverage two-level index B26, described city inland river river course first class index includes water conservancy Function two-level index B31, river course channelization degree two-level index B32, river course flexibility two-level index B33, streamflow regime two grades Index B34, riverbed silt particle composition two-level index B35, riverbed matrix type two-level index B36, Eutrophic Extent two-level index B37, water quality two-level index B38, water plant seriality two-level index B39, water plant structural intergrity two-level index B310, Indicating organism for water pollution two-level index B311, Fish two-level index B312.As it is shown on figure 3, wherein river course refers to that inland river is put down for many years All both sides, water level riverbed included below, riverbed and parts of water body, shore protection refers to the slope of more than inland river mean annual water level And bank guardrail part, buffer strip refers to beyond shore protection guardrail, does not has the land-based area area of other land used attribute.

Step 2, data process: ecological key elements different in city inland river carries out the data inputting of nondimensionalization, and adopts Determine the basic weight of each ecological key element with analytic hierarchy process (AHP), use Delphi method to be modified basis weight obtaining final Weight vectors；The rating fraction of each ecological key element is as shown in table 1.

Table 1 city inland river ecology element level score graph

In table 1, the suggestion of (1) native country vegetation type with reference to the existing complete natural type buffer strip in korneforos in local city or Vegetation type by the less buffer strip of Human disturbance；(2) mark of buffer strip and shore protection is made even after giving a mark two sides respectively Average；(3) when same city inland river difference section exists bigger gap, ecological point need to be carried out respectively for different sections Analysis, analysis result is given respectively according to different sections；(4) " the lake that Eutrophic Extent is issued according to China Environmental Monitoring General Station Pool (reservoir) Evaluation Methods For Eutrophication and classification technique regulation " (China Environmental Monitoring General Station, master station's new word [2001] 090) Being evaluated, its mild or moderate nutrient laden level is evaluated score according to moderate eutrophy；(5) instruction of water pollution is biological (resistant kind): tubificid class, moth fly, elongated chironomus larvas, beach louse, bottle spiral shell, green Euglena, quiet Euglena, the little algae that quivers, by first scenedesmus, Corner discoctaster algae, ring chlorella, fragile bristle algae, Nidus Vespae seat algae and America Herba potamogetonis distincti etc.；(cleaning refers to the instruction biology of cleaning water body Show kind): stricture of vagina Phryganeajaponica Ml., flat Fu and the naiad of Aeschna melanictera, and Cipangopaludina chinensis, ancon shank algae, bunch raw bamboo branch algae etc..

The determination utilizing analytic hierarchy process (AHP) index basis weight specifically comprises the following steps that

(1) judgment matrix is set up:

Use analytic hierarchy process (AHP) (AHP), choose under same index set same level index (such as: the B11 in A1 index set, B12, B13, B14 index), the relative importance of comparative assessment index two-by-two, form the comparator matrix of evaluation index, such as formula 1 Shown in.

Formula 1:

$A=\left(a_{ij}\right)=\left[\begin{array}{ccccc}& c_1& c_2& \mathrm{...}& c_n\\ c_1& a_{11}& a_{12}& \mathrm{...}& a_{1n}\\ c_2& a_{21}& a_{22}& \mathrm{...}& a_{2n}\\ .& .& .& & .\\ .& .& .& \mathrm{...}& .\\ .& .& .& & .\\ c_n& a_{n1}& a_{n2}& \mathrm{...}& a_{nn}\end{array}\right]$

a_ijThe employing three scale method of choosing of value obtains, it is judged that the determination of matrix element is as shown in table 2:

Table 2 judgment matrix element determines

(2) Mode of Level Simple Sequence

Calculate the characteristic vector corresponding to judgment matrix Maximum characteristic root λ max, i.e. obtain weight vectors W=(w₁, w₂..., w_n), after normalization (make in vector each element sum equal to 1) element of W be same level factor for last layer time because of The sequencing weight of certain factor relative importance of element, this process is referred to as Mode of Level Simple Sequence.

(3) consistency check

Can confirm Mode of Level Simple Sequence, need to carry out consistency check, so-called consistency check refers to determine A inconsistent Allowed band.Owing to λ continuous print depends on a_ij, then the most bigger than n of λ, the discordance of A is the most serious.Use eigenvalue of maximum Characteristic of correspondence vector is as being compared the factor weight vector to upper strata factor influence degree, and its inconsistent degree is the biggest, draws The error in judgement risen is the biggest.Thus the inconsistent degree of A can be weighed by the size of λ-n numerical value.

Definition coincident indicator: CI

Definition random index RI, RI value is as shown in table 3:

Table 3 RI value

Definition Consistency Ratio: CR=CL/RI

Typically, when Consistency Ratio CR=CL/RI is < when 0.1, it is believed that the inconsistent degree of A, within permissible range, has full The concordance of meaning, passes through consistency check.Its normalization characteristic vector available, as weight vector, otherwise to reconfigure in contrast Relatively matrix A, to a_ijAdjusted.

(4) total hierarchial sorting

Calculate the total hierarchial sorting of a certain level can obtain after normalization this layer of all factor for top relatively The weighted value of importance.

(5) consistency check of total hierarchial sorting

If B is layer B₁,B₂,…,B_nIt is CI to the Mode of Level Simple Sequence coincident indicator of factor in upper strata (A layer), random concordance For RI, then the Consistency Ratio of total hierarchial sorting is:

$CR=\frac{a_1{\mathrm{CI}}_1+a_2{\mathrm{CI}}_2+...+a_m{\mathrm{CI}}_m}{a_1{\mathrm{RI}}_1+a_2{\mathrm{RI}}_2+...+a_m{\mathrm{RI}}_m}$

Utilize Delphi method to specifically comprising the following steps that the basic weight of evaluation index is modified

Many uncertain factors impact that the comparator matrix formed in view of single expert faces, uses multidigit expert common Decision-making.Taking the expert's participative decision making of X position, the weight vectors that the judgment matrix that K expert makes is formed is: W^k=(W^k ₁, W^k ₂, W^k ₃..., W^k _n), (K=1,2,3 ..., K), if taking weight vectors WⁱWith W^jAngle be S_ij=cos (θ_ij), then S_ijRepresent two experts each Judgment matrix WⁱWith W^jBetween consistent degree.According to S_ijSeek the average homogeneity degree S of i-th Judgment Matrix According as Consistent Rule_i,

$S_i=\frac{1}{X-1}\underset{j=1,j\&NotEqual;1}{\overset{X}{\&Sigma;}}{S}_{ij}$

The average homogeneity degree of all experts is normalized, and obtains the relatively uniform degree S' of Judgment Matrix According as Consistent Rule_i, use Normalization relatively uniform degree S'_iWith respective weights multiplication of vectors suing for peace, revised weight can be obtained:

$W^{\&prime;}=\underset{i=1}{\overset{X}{\&Sigma;}}{S^{\&prime;}}_i{W}^i$

Step 3, determines the ecological index of city inland river: each for city inland river ecological key element correspondence different brackets is converted into phase The mark answered, the mark that each ecological key element correspondence different brackets is converted is 0～4 point, and mark is the highest shows that situation is the best, otherwise The poorest.

By mark and its Weight of each ecological key element, obtain city inland river ecological index UREI.UREI=f₁* W'₁+f₂*W'₂+...+f_n*W'_nWherein UREI refers to the ecological index of city inland river, and f 1-fn refers to each ecological single-factor grade Classification value, W'1-W'n is each ecological revised weighted value of single-factor.

Step 4, evaluation and test: the city inland river ecological index UREI according to obtaining carries out the evaluation and test that city inland river is ecological, When UREI >=3.2 timesharing, illustrate that this city inland river is ecological very well；When 2.4≤UREI < when 3.2, illustrates that this city inland river is ecological Property is good；When 1.6≤UREI < when 2.4, illustrates that this city inland river is ecological typically；When 0.8≤UREI < when 1.6, illustrates this city Inland river, city is ecological poor；When 0≤UREI < 0.8 timesharing, illustrate that these city inland river ecological functions almost completely lose.

Choose section, inland river before and after the regulation of ocean, Fuzhou City Li Xiyangli Sewage Plant plant area section as object of study, to based on The city inland river ecology evaluating method application of analytic hierarchy process (AHP) carries out example description.

First, based on the inland river ecological characteristic before and after the section regulation of ocean, Fuzhou City Li Xiyangli Sewage Plant plant area and construction spy Point, and set up multi-layer city inland river ecological assessment index system according to the ecological key element in city inland river, pass through step analysis Method draws each index basis weight, and utilizes Delphi method to carry out weight correction；The city inland river ecology proposed by the present invention is wanted Element rating fraction table (table 1) carries out marking to Yang Li small stream plant area section before and after regulation and evaluates, and each index weights and scores are shown in Table 5。

Evaluation result shows: the Yang Li small stream plant area front UREI=1.096 of section regulation, is reflected as ecological poor；After regulation, in advance Meter UREI=3.620, be reflected as ecological very well.

Further front 3 first class index of regulation are made a concrete analysis of.Buffer strip first class index, shore protection first class index and river course The weight score rate of first class index is respectively 53.5%, 21.7%, 24.4%.Wherein buffer strip first class index scoring rate is Height, this explanation buffer strip part ecological performance is preferable；Shore protection is due to excessive artificial reconstructed, for stone-laying form, although shore protection is hard Matter is conducive to river course stable, but runs counter to natural quality, causes its ecological functions substantially to be lost；River water body is due to riverbed Hardening and directly importing of a large amount of sanitary sewage cause water degradation, biological existence to be restricted, ecological poor.

Analyzed from above, the construction that it is critical only that ecological revetment and ecological riverway of small stream restoration of the ecosystem in ocean.

Each index score before and after table 5 Yang Li small stream plant area's section ecological evaluation metrics weight and regulation

In table 5, during Yang Lixi currently renovates, must be divided into after regulation and estimate and obtain.

Although above it has been shown and described that embodiments of the invention, it is to be understood that above-described embodiment is example Property, it is impossible to be interpreted as limitation of the present invention, those of ordinary skill in the art is without departing from the principle of the present invention and objective In the case of above-described embodiment can be changed within the scope of the invention, revise, replace and modification, be not limited solely to this Inventing the method described by above-mentioned detailed description of the invention, the most previously described mode the most preferably, and does not have restriction The meaning of property.

Claims (6)

1. a city inland river ecological multi-layer level evaluating method based on analytic hierarchy process (AHP), it is characterised in that: comprise the following steps:

Step 1, sets up index system: ecological characteristic based on city inland river and construction characteristics, and according in city inland river Ecological key element sets up multi-layer city inland river ecological assessment index system, and described ecological key element is divided into first class index and two grades Index；

Step 2, data process: ecological key elements different in city inland river carries out the data inputting of nondimensionalization, and uses layer Fractional analysis determines the basic weight of each ecological key element, uses Delphi method to be modified obtaining final weight to basis weight Vector；

Step 3, determines the ecological index of city inland river: be converted into accordingly by each for city inland river ecological key element correspondence different brackets Mark, by mark and its Weight of each ecological key element, obtains city inland river ecological index UREI；

Step 4, evaluation and test: the city inland river ecological index UREI according to obtaining carries out the evaluation and test that city inland river is ecological.

City inland river ecological multi-layer level evaluating method based on analytic hierarchy process (AHP) the most according to claim 1, its feature exists In: described step 1, described first class index includes buffer strip first class index, city inland river shore protection first class index and city inland river Water body first class index；Each first class index all includes that two-level index, described city inland river buffer strip first class index include vegetation type Two-level index, buffer strip width two-level index, community continuum two-level index, vegetation structure integrity two-level index, vegetation are covered Lid rate two-level index, described city inland river shore protection first class index include shore protection gradient two-level index, shore protection hydrophilic two-level index, Shore protection type two-level index, shore protection stability two-level index, shore protection view two-level index, vegetation coverage two-level index, institute State city inland river river course first class index and include water conservancy function two-level index, river course channelization degree two-level index, river course flexibility Two-level index, streamflow regime two-level index, riverbed silt particle composition two-level index, riverbed matrix type two-level index, eutrophication Degree two-level index, water quality two-level index, water plant seriality two-level index, water plant structural intergrity two-level index, Indicating organism for water pollution's two-level index, Fish two-level index.

City inland river ecological multi-layer level evaluating method based on analytic hierarchy process (AHP) the most according to claim 1 and 2, its feature It is: in described step 4, when UREI >=3.2 timesharing, illustrates that this city inland river is ecological very well；When 2.4≤UREI < when 3.2, Illustrate that this city inland river is ecological well；When 1.6≤UREI < when 2.4, illustrates that this city inland river is ecological typically；When 0.8≤ UREI < when 1.6, illustrates that this city inland river is ecological poor；When 0≤UREI < 0.8 timesharing, this city inland river ecological functions are described Almost completely lose.

City inland river ecological multi-layer level evaluating method based on analytic hierarchy process (AHP) the most according to claim 1 and 2, its feature Being: in described step 3, the mark that each ecological key element correspondence different brackets is converted is 0～4 point, and mark is the highest shows situation The best, on the contrary the poorest.

City inland river ecological multi-layer level evaluating method based on analytic hierarchy process (AHP) the most according to claim 2, its feature exists In: wherein river course refers to both sides, inland river mean annual water level riverbed included below, riverbed and the part of water body, in shore protection refers to Slope more than river mean annual water level and bank guardrail part, buffer strip refers to beyond shore protection guardrail, does not has other land used The land-based area area of attribute.

City inland river ecological multi-layer level evaluating method based on analytic hierarchy process (AHP) the most according to claim 1 and 2, its feature It is: the ecological evaluation and test after city inland river ecological construction or regulation of this evaluating method.