Comprehensive evaluation method for implementation effect of ecological bottom protection project of inland waterway

Abstract

The invention provides a comprehensive evaluation method for the implementation effect of an ecological bottom protection project of an inland waterway, belongs to the field of ecological environment protection of water transportation projects, and aims to overcome the limitation and deficiency of an existing evaluation method for the implementation effect of the ecological bottom protection project of the inland waterway and long-term tracking and monitoring of the ecological restoration effect of the method. Comprising an inland waterway ecological bottom protection project comprehensive evaluation index system, a subitem index weight and scoring criterion system based on the inland waterway ecological bottom protection project comprehensive evaluation index system, and an inland waterway ecological bottom protection project implementation effect evaluation criterion system based on a bottom protection project ecological conformity index (ECIR-RBPE). A clear, complete, detailed and quantifiable evaluation criterion system is provided for the evaluation of the implementation effect of the ecological bottom protection project of the inland waterway, so that a simple, easy and economical evaluation method is provided for guiding the structural design, material selection, engineering arrangement and ecological system recovery effect long-term tracking and monitoring of the ecological bottom protection project of the inland waterway.

Description

Technical Field

[0001] The invention provides a comprehensive evaluation method for the implementation effect of an inland waterway ecological bottom protection project, belonging to the technical field of ecological environment protection and evaluation of water transport projects. Background Art

[0002] (1) Definition and connotation of ecological bottom protection

[0003] As an important part of inland waterway regulation projects, bottom protection projects have traditionally adopted scattered bottom protection such as riprap, row-type bottom protection, group-type frames or components, etc. to protect the riverbed or regulation projects from water erosion, emphasizing the stability and safety of the structure. However, these bottom protection structures artificially block the longitudinal connectivity and continuity of the river, often causing the loss of large benthic animal biomass and biodiversity. In recent years, the construction of ecological bottom protection projects has become a development trend of waterway regulation projects at home and abroad, and it is also an important way to achieve river biodiversity protection and water ecological restoration. The construction of ecological bottom protection not only meets the requirements of waterway engineering design, but also facilitates the settlement and growth of large benthic animals, provides suitable habitats and habitats for aquatic organisms, and improves the stability of the river ecosystem.

[0004] Based on the research of scholars at home and abroad in recent years, the ecological bottom protection of inland waterways can be defined as the use of natural or artificial materials, artificially constructed on the riverbed or the base of the regulation structure in a certain spatial layout and structural form and adapted to its deformation, so as to achieve the effect of slowing down the flow and promoting siltation, preventing riverbed scouring, and stabilizing the regulation structure. At the same time, it is convenient for the material exchange between the overlying water body and sediment, which is conducive to the settlement and growth of large benthic animals, aquatic plants and attached organisms, and can provide a certain habitat for aquatic swimming animals, thereby meeting the engineering design and navigation goals, and achieving the unity of structural stability, material ecology, engineering layout rationality, engineering economy and river ecosystem service functions. Therefore, the comprehensive evaluation of the implementation effect of the inland waterway ecological bottom protection project involved in the present invention includes five major connotations: structural stability, material ecology, engineering layout rationality, engineering economy and ecosystem service functions.

[0005] (2) Research status of new ecological bottom protection structures and evaluation systems

[0006] In recent years, a series of new ecological bottom protection structures such as concrete block soft-body rafts, D-type soft-body rafts, sand wave ballast block soft-body rafts, and permeable frames have been adopted in the implementation of inland waterway regulation projects such as the Yangtze River, and beneficial explorations have been carried out in the construction of ecological bottom protection for inland waterways. Tracking the current status of related research shows that there are relatively few studies on the comprehensive evaluation of the implementation effect of ecological bottom protection in China, and the corresponding evaluation index system has not yet been established. For example:

[0007] 1) Gao Zhifeng conducted an analysis of the pros and cons of various bottom protection schemes for inland waterway regulation projects. Through engineering cases, the article discussed in detail the pros and cons of each scheme, namely, mold bag concrete bottom protection, concrete hinged row bottom protection, cast-in-place concrete bottom protection or cast-in-place block stone bottom protection, from the aspects of applicability and limitations, so as to provide options for different inland waterway regulation projects. The article simply qualitatively compared the pros and cons of various traditional bottom protection schemes from the aspects of soil quality, navigation section, revetment nature, environmental protection, cost, construction conditions, etc., with few indicators, and is not suitable for the comprehensive evaluation of the engineering characteristics and implementation ecological effects of inland waterway ecological bottom protection (China Water Transport, 2022, (1), pp133-135);

[0008] 2) Cao Minxiong, Shen Xia and Ying Hanhai conducted research on the structure of ecologically regulated buildings for the deep-water channel below Nanjing on the Yangtze River. They developed ecological bottom protection structures such as space row bodies, active hook-type bodies, and twisted double I-shaped permeable frames. They also briefly analyzed the mechanism of action of various ecological bottom protection structures. The results showed that various structures achieved significant economic and ecological benefits and had good promotion and application value. However, the paper did not conduct a quantitative comprehensive evaluation of the implementation effects of various ecological bottom protections in the first and second phases of the 12.5m deep-water channel below Nanjing on the Yangtze River, nor did it establish a corresponding evaluation index system (Water Transport Engineering, 2018, (1), pp1-11);

[0009] 3) Liu Qifeng, Zhu Yuanzhang, Huang Wei and Chen Yijun discussed the design concept of the riverbank protection project in the middle and lower reaches of the Yangtze River, and introduced the underwater ecological structure including the structural forms and applications of permeable frames and fish nests. However, the paper did not conduct a comprehensive evaluation of the implementation effect of the underwater ecological structure, nor did it establish a corresponding evaluation index system (Water Resources and Hydropower Express, 2017, 38(11), pp53-55+78);

[0010] 4) Chai Huafeng reviewed the innovations of the Jingjiang River channel regulation project in new structures such as bottom protection (beach), high beach protection engineering and dam construction, and proposed new bottom protection structures such as D-type interlocking rows, one-time permeable frames, and new flexible water grass mats. However, the article did not conduct a comprehensive evaluation of the implementation effect of the new bottom protection structure, and also lacked a corresponding evaluation index system (China Water Transport, 2016, (1), pp43-50);

[0011] 5) Niu Lanhua, Li Yunzhong and Du Linxia analyzed the evolution trend of the control nodes of the downstream section of the Three Gorges Project dam based on the prototype observation data, and conducted long-term tracking observation and analysis of the bottom protection test project of the Yanzhi Dam node, one of the control nodes. They believed that the use of riprap filling and concrete agglomeration soft bottom protection projects has a significant effect on riverbed stability and anti-scouring. The article analyzed the protective effect of the bottom protection project from the aspects of siltation height and siltation amount, riverbed roughness, etc., but did not establish a corresponding evaluation index system and carry out a comprehensive evaluation of the implementation effect (Journal of Yangtze River Scientific Research Institute, 2014, 31(6), pp123-129);

[0012] 6) Li Yibing and Cheng Xiaobing, based on the research and analysis of green and environmentally friendly waterway regulation buildings in the middle and lower reaches of the Yangtze River, summarized the characteristics and practicality of existing green and environmentally friendly materials and processes that can be used for waterway regulation, proposed the structural form and materials of green and environmentally friendly regulation buildings, and clarified the applicable parts of these materials and structures in surface protection, bottom protection, beach protection and bank protection projects. The paper neither conducted a comprehensive evaluation of the implementation effect of the bottom protection structure nor established a corresponding evaluation index system (Waterways and Ports, 2012, 33(5), pp397-404);

[0013] 6) Wu Peng, Jiang Junjie, and Cao Fengshuai introduced the types and main functions of geosynthetics, summarized their applications in water transport engineering, elaborated on the research and engineering practice of related aspects such as bottom protection soft-body rafts and active hook-and-loop rafts, and pointed out the further application and development direction of geosynthetics (Water Transport Engineering, 2017, (6), pp16-22);

[0014] 7) Peng Hao, Li Biao, Sun Baohu, Ouyang Fei, Wen Guonan, Zhou Peng, and Fu Lin published an ecological bottom protection ballast structure, which solved the problem that the existing bottom protection structure has poor siltation and flow slowing effect. The structure can provide a larger habitat space for benthic organisms and improve the ecological effect of the riverbed (China, CN221398844 U);

[0015] 8) Peng Hao, Li Biao, Zhang Yu, Ouyang Fei, Sun Baohu, Wen Guonan, Li Qiang, Li Peng, and Zhou Xiaochao published an ecological bottom protection structure of porous concrete with the function of promoting siltation and slowing down flow. The structure can reduce the flow velocity near the bottom protection structure from multiple directions and play a role in protecting the stability of the bottom protection structure (China, CN219298114 U);

[0016] 9) Peng Hao, Li Biao, Sun Baohu, Guo Min, Zhang Qin, Zhang Wen, Li Qiang, Cheng Zheng, Xu Xiuzhi, Wang Yaxuan, Geng Lei, and Li Peng published an ecological concrete bottom plate structure that promotes siltation and slows down the flow. The structure is conducive to the sedimentation, enhances the siltation promotion and slowing down flow and bottom protection effects of the bottom protection structure, and uses the distributed thick and thin PVC hollow tube bundles to simulate clustered plants, which can increase the living space of fish and benthic organisms (China, CN218436887 U);

[0017] In summary, the sources of materials for inland waterway ecological bottom protection projects are becoming increasingly extensive, new structural forms are constantly emerging, and are increasingly becoming the main trend and development direction of inland waterway regulation at home and abroad. It is urgent to study and establish a guiding and operational comprehensive evaluation index system and evaluation method for the implementation effect of inland waterway ecological bottom protection projects based on the above-mentioned background technology to provide support, so as to guide the structural design, material selection, engineering construction and implementation of inland waterway ecological bottom protection projects. Comprehensive evaluation of the ecological effects will serve the long-term monitoring of river ecosystem protection and restoration status, so as to continuously improve the level of ecological construction of inland waterways. Summary of the invention

[0018] (1) Purpose of the Invention

[0019] In view of the limitations and shortcomings of the existing comprehensive evaluation methods for the implementation effects of inland waterway ecological bottom protection engineering and the long-term tracking and monitoring of its ecological restoration effects, the present invention provides a comprehensive evaluation method for the implementation effects of inland waterway ecological bottom protection engineering. It includes three parts: a comprehensive evaluation index system for inland waterway ecological bottom protection engineering, a weight and scoring criterion system for each sub-index based on the comprehensive evaluation index system for inland waterway ecological bottom protection engineering, and an evaluation criterion system for the implementation effects of inland waterway ecological bottom protection engineering based on the ecological compliance index of bottom protection engineering (ECIR-RBPE). The present invention provides a clear, complete, detailed and quantifiable evaluation criterion system for the evaluation of the implementation effects of inland waterway ecological bottom protection engineering, and provides a simple, easy and economical evaluation method for guiding the structural design, material selection, engineering construction and long-term tracking and monitoring of ecological restoration effects of inland waterway ecological bottom protection.

[0020] (2) Technical solution

[0021] The technical solution adopted by the present invention to solve its technical problems is: to provide a comprehensive evaluation method for the implementation effect of an inland waterway ecological bottom protection project, which consists of three parts: a comprehensive evaluation index system for inland waterway ecological bottom protection projects, a weight and scoring criterion system for each sub-indicator based on the comprehensive evaluation index system for inland waterway ecological bottom protection projects, and an evaluation criterion system for the implementation effect of inland waterway ecological bottom protection projects based on the Ecological Compliance Index of Bottom Protection Projects (ECIR-RBPE).

[0022] The comprehensive evaluation index system of the inland waterway ecological bottom protection project has the following characteristics: it is composed of two levels of five indicators and 14 sub-indicators, among which the first level contains five indicators: A1 structural stability, A2 material ecology, A3 engineering layout rationality, A4 engineering economy, and A5 ecosystem service function; the second level contains 14 sub-indicators, which correspond to the five indicators A1, A2, A3, A4, and A5 respectively. The specific corresponding relationships are as follows:

[0023] 1) The A1 structural stability index corresponds to two sub-indicators: A11 water flow erosion resistance and A12 slow flow and siltation promoting characteristics;

[0024] 2) A2 Material Ecological Index corresponds to the following two sub-indicators: A21 The proportion of natural materials and A22 The durability of artificial organic synthetic materials;

[0025] 3) The A3 engineering layout rationality index corresponds to the following two sub-indicators: A31 riverbed morphological stability and A32 engineering disturbance ratio;

[0026] 4) The A4 project economic index corresponds to the following three sub-indicators: A41 project cost economy, A42 project construction difficulty, and A43 project operation and maintenance difficulty;

[0027] 5) The A5 ecosystem service function indicator corresponds to the following five sub-indicators: A51 vertical connectivity, A52 conducive to the penetration of aquatic plant roots or the growth of attached organisms, A53 the number and density of large benthic animal species, A54 conducive to the creation of diverse habitats and habitats, and A55 alien invasive species.

[0028] See the schematic diagram for describing the comprehensive evaluation index system of the above-mentioned inland waterway ecological bottom protection project. Figure 1 .

[0029] The weights and scoring criteria system of each sub-index based on the comprehensive evaluation index system of inland waterway ecological bottom protection projects includes the weight values ​​of the above-mentioned two-level 5-category indicators and the 14 sub-indexes they contain, as well as the qualitative or quantitative evaluation criteria of 5 levels. The different levels of the 14 sub-indexes are divided into 5 levels, and the scores assigned are decreasing, namely 5 points (excellent), 4 points (good), 3 points (medium), 2 points (poor), and 1 point (poor). The specific evaluation criteria are as follows:

[0030] 1) A11 water flow erosion resistance (weight 0.13): very stable (no erosion traces, the structural integrity rate of the ecological bottom protection project area is ≥85%), relatively stable (occasional erosion traces, the structural integrity rate of the project area is 70-85%), generally stable (moderate erosion, the structural integrity rate of the project area is 50-70%), relatively unstable (more erosion, the structural integrity rate of the project area is 30-50%), unstable (large erosion, the structural integrity rate of the project area is <30%);

[0031] 2) A12 slow flow and siltation-promoting characteristics (weight 0.13): very good (significant sediment accumulation in the ecological bottom protection project area, with an average sedimentation height of more than 0.3m), good (significant sediment accumulation in the project area, with an average sedimentation height of 0.1-0.3m), medium (sediment accumulation in the project area, with an average sedimentation height of 0-0.1m), poor (no obvious sediment accumulation in the project area), very poor (no sedimentation in the project area, and obvious signs of scouring);

[0032] 3) A21 Ratio of natural materials (weight 0.08): 80-100% (the mass ratio of natural materials used in ecological bottom protection projects per unit area is determined, and concrete and stones can be considered natural materials), 60%-80%, 40%-60%, 20%-40%, <20%;

[0033] 4) A22 Durability of artificial organic synthetic materials (weight 0.08): no artificial organic synthetic materials, durability of artificial organic synthetic materials over 50 years, durability of artificial organic synthetic materials 20-50 years, durability of artificial organic synthetic materials 10-20 years, durability of artificial organic synthetic materials 5-10 years;

[0034] 5) A31 Riverbed morphology stability (weight 0.08): After the implementation of the ecological bottom protection project, the riverbed morphology and scouring and silting in the project area remain stable; the riverbed morphology and scouring and silting in the project area remain basically stable; the riverbed morphology and scouring and silting in the project area change slightly; the riverbed morphology and scouring and silting in the project area change significantly; the riverbed morphology and scouring and silting in the project area undergo major adjustments;

[0035] 6) A32 engineering disturbance ratio (weight 0.08): <20% (the ratio of the disturbance area of ​​the ecological bottom protection project area to the total riverbed area of ​​the river section), 20%-40%, 40%-60%, 60%-80%, 80-100%;

[0036] 7) A41 Project cost economy (weight 0.05): very good (measured from the project cost, the ratio of ecological bottom protection project to traditional bottom protection project ≤ 1.0), good (1.0-1.5), medium (1.5-2), poor (2-3), very poor (3 and above);

[0037] 8) A42 project construction difficulty (weight 0.05): very good (measured by the difficulty of project construction, the ratio of ecological bottom protection project to traditional bottom protection project ≤ 1.0), good (1.0-1.5), medium (1.5-2), poor (2-3), very difficult (3 and above);

[0038] 9) A43 Project O&M Difficulty (weight 0.05): simple (basically no maintenance required), good (simple and small amount of maintenance), medium (maintenance required every 3-5 years), poor (maintenance required every 1-2 years), complex (requires continuous maintenance every year);

[0039] 10) A51 vertical connectivity (weight 0.06): vertical connectivity maintains a natural state, the structure of the ecological bottom protection does not affect the material exchange between the overlying water and sediment, the vertical connectivity is good, the material exchange between the overlying water and sediment is less affected, the vertical connectivity is average, the material exchange between the overlying water and sediment is moderately affected, the vertical connectivity is poor, the material exchange between the overlying water and sediment is difficult, the vertical connectivity is completely blocked, and the overlying water and sediment materials are completely isolated;

[0040] 11) A52 is conducive to the penetration of aquatic plant roots or the growth of attached organisms (weight 0.06): The structure and engineering layout of the ecological bottom protection are very conducive to the penetration of aquatic plant roots and the growth of attached organisms, the structure and engineering layout are conducive to the penetration of aquatic plant roots and the growth of attached organisms, the structure and engineering layout are convenient for the penetration of aquatic plant roots and the growth of attached organisms, the structure and engineering layout are not conducive to the penetration of aquatic plant roots and the growth of attached organisms, and the structure and engineering layout are extremely unfavorable to the penetration of aquatic plant roots and the growth of attached organisms;

[0041] 12) A53 Number and density of large benthic animal species (weight 0.06): the ratio of the number or density of large benthic animal species in the ecological bottom protection project area to that in the area without bottom protection is 80% or more, the ratio of the number or density of large benthic animal species in the project area to that in the area without bottom protection is 60-80%, the ratio of the number or density of large benthic animal species in the project area to that in the area without bottom protection is 40-60%, the ratio of the number or density of large benthic animal species in the project area to that in the area without bottom protection is 20-40%, the ratio of the number or density of large benthic animal species in the project area to that in the area without bottom protection is less than 20%;

[0042] 13) A54 is conducive to the creation of diverse habitats and habitats (weight 0.05): The structure and engineering layout of the ecological bottom protection are very conducive to the creation of diverse habitats and habitats, the structure and engineering layout are conducive to the creation of diverse habitats and habitats, the structure and engineering layout are convenient for biological settlement and habitat, the structure and engineering layout are not conducive to biological settlement and habitat, and the structure and engineering layout are extremely unfavorable for biological settlement and habitat;

[0043] 14) A55 Invasive alien species (weight 0.04): No invasive alien species; Occasional invasive alien species do not cause much harm; Common invasive alien species have not caused any harm to the ecological environment; Common invasive alien species have formed stable populations and caused harm to the ecological environment; Invasive alien species are dominant and cause serious harm to local species and the ecological environment.

[0044] The evaluation criteria system for the implementation effect of the inland waterway ecological bottom protection project based on the ecological compliance index of the bottom protection project (ECIR-RBPE) includes the ecological compliance index of the bottom protection project (ECIR-RBPE) and the evaluation criteria system for the ecological compliance degree of the inland waterway ecological bottom protection project, and the specific contents include:

[0045] 1) The calculation method of the ecological compliance index of the bottom protection project (ECIR-RBPE) is as follows: the weight of each of the 14 sub-indicators is multiplied by the obtained score and then added together to obtain the ecological compliance index of the bottom protection project to be evaluated;

[0046] 2) The evaluation criteria system for the ecological compliance of the inland waterway ecological bottom protection project is as follows: based on the calculated ecological compliance index of the bottom protection project (ECIR-RBPE) score, the implementation effect of the inland waterway ecological bottom protection project is judged according to the following evaluation criteria: when ECIR-RBPE ≥ 4 points, the evaluation grade is excellent, indicating that the ecological compliance of this type of ecological bottom protection is very high; when 3 points ≤ ECIR-RBPE < 4 points, the evaluation grade is good, indicating that the ecological compliance of this type of ecological bottom protection is good; when 2 points ≤ ECIR-RBPE < 3 points, the evaluation grade is medium, indicating that the ecological compliance of this type of ecological bottom protection is medium; when 1 point ≤ ECIR-RBPE < 2 points, the evaluation grade is poor, indicating that the ecological compliance of this type of ecological bottom protection is poor; when ECIR-RBPE < 1 point, the evaluation grade is poor, indicating that the ecological compliance of this type of ecological bottom protection is poor.

[0047] (3) Advantages and effects

[0048] The advantage of the present invention is that it creates a comprehensive evaluation method for the implementation effect of inland waterway ecological bottom protection projects, which includes a comprehensive evaluation index system for inland waterway ecological bottom protection projects, a weight and scoring criterion system for each sub-item index based on the comprehensive evaluation index system for inland waterway ecological bottom protection projects, and an evaluation criterion system for the implementation effect of inland waterway ecological bottom protection projects based on the ecological compliance index of bottom protection projects (ECIR-RBPE). Its advantages and effects are reflected in the following aspects:

[0049] 1) The constructed comprehensive evaluation index system of inland waterway ecological bottom protection projects includes two levels and five types of indicators, including structural stability, material ecology, engineering layout rationality, engineering economy, ecosystem service function indicators and 14 sub-indicators, which provides a clear and complete evaluation index system for the implementation effect evaluation of inland waterway ecological bottom protection projects;

[0050] 2) The constructed system of weights and scoring criteria for each sub-index of the comprehensive evaluation index system of inland waterway ecological revetment projects includes two levels of five types of indicators and the weight values ​​of each of the 14 sub-indexes and five levels of qualitative or quantitative evaluation criteria, which provides a detailed and quantifiable evaluation criterion system for the evaluation of the implementation effect of inland waterway ecological revetment projects;

[0051] 3) The constructed inland waterway ecological bottom protection project implementation effect evaluation criterion system based on the ecological compliance index of bottom protection projects (ECIR-RBPE), including the ecological compliance index of bottom protection projects (ECIR-RBPE) and its 5 score levels, provides a simple, easy and economical evaluation method for quantitatively evaluating the ecological restoration effect of ecological bottom protection projects, and for guiding the structural design, material selection, engineering construction and long-term tracking and monitoring of ecological restoration effects of inland waterway ecological bottom protection projects.

[0052] The present invention makes up for the lack of long-term tracking and monitoring technology of the ecological restoration effect of inland waterway ecological bottom protection projects, fills the gap in the comprehensive evaluation method of the implementation effect of inland waterway ecological bottom protection projects, and provides technical support for the evaluation of inland ecological waterway construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 : Comprehensive evaluation index system for the implementation effect of inland waterway ecological bottom protection projects;

[0054] Figure 2 ; Spatial body ecological row structure layout diagram

[0055] Figure 3 : Active hook structure diagram

[0056] Figure 4 :New permeable frame structure diagram DETAILED DESCRIPTION

[0057] The following further describes the implementation of the present invention in conjunction with the accompanying drawings and examples.

[0058] The "Phase II Project of 12.5-meter Deepwater Channel below Nanjing on the Yangtze River" (hereinafter referred to as "Phase II Project") focuses on the improvement of Fujiangsha Waterway, Kouanzhi Waterway, Hechangzhou Waterway and Yizheng Waterway, involving a total length of 227 kilometers of river sections. The project started in June 2015 and was completed and accepted in June 2017. This section takes the three types of ecological bottom protection adopted by the "Phase II Project" as specific implementation cases: spatial ecological row, active hook-connected body, and new permeable frame. By reviewing relevant engineering design documents, consulting the engineering construction command and conducting on-site investigations, a comprehensive analysis was conducted, and the sub-item indicators of these three typical ecological bottom protection projects and traditional riprap bottom protection projects were scored with reference to the comprehensive evaluation index system and scoring criteria system for inland waterway ecological bottom protection projects, and the ecological compliance index (ECIR-RBPE) of these four bottom protection projects was calculated and the project implementation effect was evaluated. The weights of each sub-item indicator and scoring criteria system of the comprehensive evaluation index system for inland waterway ecological bottom protection projects are detailed in Table 1.

[0059] Table 1 Weights and scoring criteria for comprehensive evaluation indicators of the implementation effect of inland waterway ecological bottom protection projects

[0060]

[0061]

[0062] This case spatial body ecological row ( Figure 2 ), its structure adopts the traditional arrangement + new ecological space body ballast solution, the arrangement adopts the conventional arrangement, and adopts 150g / m 2 Non-woven fabric with 350g / m 2 Filament woven fabric composite, in order to strengthen the layout strength, set up 2 7cm polypropylene reinforcement belts, arrange new ecological space body on the layout, form a three-dimensional space with large air permeability, so as to slow down the bottom flow velocity of water body and provide suitable habitat for organisms, the outline size of ballast block is 60cm×60cm×40cm (length×width×height), composed of top plate, bottom plate and four columns, and the material is C30 concrete; active hook body, its structure adopts 7-sided three-dimensional structure with side length of 60cm, cross section of 6cm×6cm and wall thickness of 2-3mm, and the material is polypropylene as base material and barium sulfate as weight-increasing material, and a variety of additives are added in a certain proportion, which has the effect of slowing down flow and promoting siltation, and will not hinder the connection between water body and sediment ( Figure 3 ); The new permeable frame adopts double I-shaped reinforced concrete as the overall material, the diameter of the built-in steel bar is 8mm, the concrete strength grade is C30, and the frame structure size is 800mm×100mm×100mm. The structure has the effect of slowing down the flow and promoting siltation, will not hinder the exchange of water and soil, has the effect of water and sand permeability, is an eco-friendly structure, can play the role of artificial fishing reefs, and the interior of the frame can provide a habitat for fish and other aquatic organisms ( Figure 4 ).

[0063] The specific scoring results of the comprehensive evaluation of the implementation effects of the three types of ecological bottom protection in this case, including spatial ecological row, active hook connection, new permeable frame and traditional riprap bottom protection engineering, are as follows:

[0064] 1) A11 Water flow erosion resistance: According to the survey, the structures of the three ecological bottom protection test sections, namely, the spatial ecological row, the active hook connection, and the new permeable frame, are relatively stable, with only occasional small amounts of erosion. They were all rated 4 points. The traditional riprap bottom protection project area is very stable as sediments accumulate between the stones. This item is rated 5 points.

[0065] 2) A12 Slow flow and siltation-promoting characteristics: According to the survey, the sediment particle size in the spatial ecological drainage project area is relatively uniform, and the siltation height is less than 0.10m, which is rated 3 points. The active hook-connected project area has a significant siltation-promoting effect, with an average siltation height of 0.48m, which is rated 5 points. The siltation effect in the new permeable frame project area is relatively obvious, with an average siltation height of 0.27m, which is rated 4 points. The sediment in the traditional riprap bottom protection project area has not yet filled the gaps between the stones, and no obvious sediment accumulation has occurred, which is rated 2 points.

[0066] 3) A21 The proportion of natural materials: According to the relevant design documents of the ecological bottom protection project, the space body of the ecological row is made of concrete, and the layout adopts conventional layout, which is artificial synthetic material. The mass of natural materials accounts for about 85%, and this item is rated 5 points. The active hook-connected body uses polypropylene as the base material and barium sulfate as the weight-increasing material. In addition, a variety of additives are added in a certain proportion. The mass of natural materials accounts for about 75%, and this item is rated 4 points. The new permeable frame uses reinforced concrete material, which is rated 5 points. The riprap bottom protection material is block stone, and the natural material accounts for 100%, which is rated 5 points.

[0067] 4) A22 Durability of artificial organic synthetic materials: According to the relevant design documents of the ecological bottom protection project, the durability of the artificial organic synthetic materials of the space ecological row in the clean water body is more than 50 years, and this item is rated 4 points. The durability of the active hook-connected polypropylene is also more than 50 years, and this item is rated 4 points. The new permeable frame has no artificial organic synthetic materials, and this item is rated 5 points. The riprap bottom protection is all natural materials, and this item is rated 5 points.

[0068] 5) A31 Riverbed morphology stability: After consulting the relevant design documents of the ecological bottom protection project and conducting on-site investigations, it was found that after the implementation of the project, the riverbed morphology and scouring and silting of the Yangtze River in the river sections where these bottom protection projects were located remained stable, and no obvious scouring occurred. This item was rated 5 points;

[0069] 6) A32 Project disturbance ratio: According to the relevant design documents of ecological bottom protection projects, the disturbance area of ​​the four types of bottom protection projects in the project area accounts for less than 20% of the riverbed area of ​​the river section, and this item is rated 5 points;

[0070] 7) A41 Cost-effectiveness of the project: After consulting the relevant design documents of the ecological bottom protection project and the engineering construction command, the cost of the spatial ecological drainage is 1.5-2 times that of the traditional concrete block soft drainage bottom protection project compared with the traditional bottom protection project. This item is rated 3 points. The cost of the active hook-type and new permeable frame project is 1.0-1.5 times that of the traditional group frame or component bottom protection project. This item is rated 4 points. The riprap bottom protection project is rated 5 points.

[0071] 8) Construction difficulty of A42 project: Check the relevant design documents of ecological bottom protection project and consult the engineering construction command. The space body ecological row needs to prefabricate the space body, assemble, process and reinforce the arrangement, etc. The laying process is basically the same as the traditional concrete block soft row, which is basically 1.5-2 times of the traditional project. This item is rated 3 points. The active hook connection can be assembled by a single part and then randomly thrown, or the hook connection can be tied to each other and the grid, and then the grid is lowered by the laying ship and the ship is moved to complete the construction, which is basically 1.5-2 times of the traditional project. This item is rated 3 points. The new permeable frame is made of molds and placed on a special ship loading platform. It is thrown by the construction ship, which is basically 1.0-1.5 times of the traditional project. This item is rated 4 points. The riprap revetment bottom project is rated 5 points;

[0072] 9) Difficulty of A43 project operation and maintenance: Through consultation with the project construction headquarters and on-site investigation, the spatial ecological drainage, active hook-connected body and new permeable frame bottom protection project are basically intact after one year of operation, and only require simple and small maintenance. This item is rated 4 points. The traditional riprap bottom protection project basically does not require maintenance during the operation period, and this item is rated 5 points;

[0073] 10) A51 longitudinal connectivity: According to the survey, the layout of the space body ecological row adopts conventional layout, using 150g / m 2 Non-woven fabric with 350g / m 2 The composite of filament woven fabric basically blocks the exchange of materials between the overlying water and sediment, so the longitudinal connectivity is poor, and this item is rated 2 points; the active hook connector and the new permeable frame will not block the material exchange between the overlying water and sediment, and the longitudinal connectivity is good, and this item is rated 4 points. The traditional riprap bottom protection can realize the material exchange between the overlying water and sediment through the gaps between the stones, and the longitudinal connectivity is general, and this item is rated 3 points;

[0074] 11) A52 is conducive to the penetration of aquatic plant roots or the growth of attached organisms: According to the on-site investigation, although the space of the space ecological row is very conducive to the attachment and growth of aquatic organisms, the layout is not conducive to the growth of aquatic plant roots. This item is rated 4 points. The active hook connection and the new permeable frame have the ecological function of artificial fishing reefs. Their structure and layout are convenient for reducing the water flow rate, which is very conducive to the penetration of aquatic organism roots and the growth of attached organisms. This item is rated 5 points. The traditional riprap bottom protection project is conducive to the attachment and growth of aquatic organisms. This item is rated 3 points.

[0075] 12) A53 Number or density of large benthic animals: According to the on-site investigation, 4 large benthic animals were detected in the area without bottom protection, 6 large benthic animals were detected in the area of ​​spatial ecological drainage project, accounting for 150%, and this item was rated 5 points. 4 large benthic animals were detected in the area of ​​active hook-and-loop project, accounting for 100%, and this item was rated 5 points. 4 large benthic animals were detected in the area of ​​new permeable frame project, accounting for 100%, and this item was rated 5 points. No large benthic animals were detected in the area of ​​traditional riprap bottom protection project, accounting for less than 20%, and this item was rated 1 point.

[0076] 13) A54 is conducive to creating diverse habitats and habitats: According to the on-site investigation, the new ecological space body of the space body ecological row can form a three-dimensional space with large air permeability, which is very conducive to creating diverse habitats and habitats. This item is scored 5 points. The active hook-connected body and the new permeable frame engineering area have high air permeability and play the role of artificial fishing reefs. The interior of the frame can provide a shelter for fish and other aquatic organisms, which is conducive to creating diverse habitats and habitats. This item is scored 4 points. The traditional riprap bottom protection engineering area is not conducive to the settlement and habitat of organisms, and is not conducive to the creation of diverse habitats and habitats. This item is scored 2 points;

[0077] 14) A56 Invasive alien species: According to the results of on-site investigations and the List of Key Invasive Alien Species under Management, no invasive alien species were found in these four bottom protection engineering areas, and this item was scored 5 points.

[0078] The scoring results of each sub-indicator of the comprehensive evaluation of the implementation effect of the second phase ecological bottom protection project are detailed in Table 2.

[0079] Table 2 Comprehensive evaluation results of the implementation effect of the ecological bottom protection project for the 12.5-meter deep-water channel below Nanjing on the Yangtze River

[0080]

[0081] According to the calculation method and evaluation criteria of the ecological compliance index (ECIR-RBPE) of the bottom protection engineering, the ecological compliance index (ECIR-RBPE) values ​​of the four bottom protection engineering of the second phase project, namely, the spatial ecological row, the active hook-connected body, the new permeable frame, and the traditional riprap bottom protection, were calculated (see Table 2 for details), and the evaluation and grading were carried out. The results show that the ecological compliance index (ECIR-RBPE) of the bottom protection engineering of the spatial ecological row is 4.04, with an excellent evaluation grade, the ecological compliance index (ECIR-RBPE) of the bottom protection engineering of the active hook-connected body is 4.40, with an excellent evaluation grade, the ecological compliance index (ECIR-RBPE) of the bottom protection engineering of the new permeable frame is 4.48, with an excellent evaluation grade, and the ecological compliance index (ECIR-RBPE) of the bottom protection engineering of the traditional riprap bottom protection is 3.98, with a good evaluation grade.

[0082] Therefore, the comprehensive evaluation results of the implementation effect of the ecological bottom protection project of the second phase project show that the new permeable frame and active hook-type connection have the best ecological restoration effect, the spatial ecological row has the second best ecological restoration effect, and the traditional riprap bottom protection has a relatively poor ecological restoration effect.

Claims

1. A comprehensive evaluation method for the implementation effect of inland waterway ecological bottom protection projects, which consists of three parts: a comprehensive evaluation index system for inland waterway ecological bottom protection projects, a weight and scoring criterion system for each sub-index based on the comprehensive evaluation index system for inland waterway ecological bottom protection projects, and an evaluation criterion system for the implementation effect of inland waterway ecological bottom protection projects based on the ecological compliance index ECIR-RBPE of bottom protection projects; The comprehensive evaluation index system of inland waterway ecological bottom protection projects is as follows: Its characteristics are as follows: It consists of two levels of five indicators and their 14 sub-indicators. The first level includes five indicators: A1 structural stability, A2 material ecology, A3 engineering layout rationality, A4 engineering economy, and A5 ecosystem service function; the second level includes 14 sub-indicators, which correspond to the five indicators A1, A2, A3, A4, and A5 respectively; The specific corresponding relationships are as follows: (1) The A1 structural stability index corresponds to two sub-indicators: A11 water flow erosion resistance and A12 slow flow and sedimentation promoting characteristics; (2) The A2 material ecological index corresponds to the following two sub-indicators: A21 the proportion of natural materials and A22 the durability of artificial organic synthetic materials; (3) The A3 engineering layout rationality index corresponds to the following two sub-indicators: A31 riverbed morphological stability and A32 engineering disturbance ratio; (4) The A4 project economic index corresponds to the following three sub-indicators: A41 project cost economics, A42 project construction difficulty, and A43 project operation and maintenance difficulty; (5) The A5 ecosystem service function indicator corresponds to the following five sub-indicators: A51 vertical connectivity, A52 conducive to the penetration of aquatic plant roots or the growth of attached organisms, A53 the number and density of large benthic animal species, A54 conducive to the creation of diverse habitats and habitats, and A55 alien invasive species; The weight and scoring criteria system of each sub-index based on the comprehensive evaluation index system of the inland waterway ecological bottom protection project includes the weight values ​​of the above-mentioned two-level 5-category index and the 14 sub-indexes contained therein and the qualitative or quantitative evaluation criteria of 5 grades, wherein the different grades of each index of the 14 sub-items are divided into 5 grades, and the scores assigned are decreasing, in order of 5 points, the grade is excellent; 4 points, the grade is good; 3 points, the grade is medium; 2 points, the grade is poor; 1 point, the grade is poor; The specific evaluation criteria are as follows: 1) A11 Water flow erosion resistance, the weight of this sub-index is 0.13: very stable, no erosion marks, the structural integrity rate of the ecological bottom protection project area is ≥85%; relatively stable, occasional erosion marks, the structural integrity rate of the project area is 70-85%; generally stable, moderate erosion, the structural integrity rate of the project area is 50-70%; relatively unstable, more erosion, the structural integrity rate of the project area is 30-50%; unstable, a lot of erosion, the structural integrity rate of the project area is <30%; 2) A12 Slow flow and siltation-promoting characteristics, the weight of this sub-index is 0.13: Very good, the sediment accumulation in the ecological bottom protection project area is significant, and the average sedimentation height is above 0.3m; Good, the sediment accumulation in the project area is relatively obvious, and the average sedimentation height is 0.1-0.3m; Medium, sediments appear in the project area, and the average sedimentation height is 0-0.1m; Poor, no obvious sediment accumulation appears in the project area; Very poor, no sedimentation appears in the project area, and there are obvious signs of scouring; 3) A21 The proportion of natural materials, the mass proportion of natural materials used in ecological bottom protection projects per unit area. Concrete and stone can be considered natural materials. The weight of this sub-indicator is 0.08: 80-100%; 60%-80%; 40%-60%; 20%-40%; <20%; 4) A22 Durability of artificial organic synthetic materials, the weight of this sub-index is 0.08: no artificial organic synthetic materials; durability of artificial organic synthetic materials is more than 50 years; durability of artificial organic synthetic materials is 20-50 years; durability of artificial organic synthetic materials is 10-20 years; durability of artificial organic synthetic materials is 5-10 years; 5) A31 Riverbed morphology stability, the weight of this sub-index is 0.08: After the implementation of the ecological bottom protection project, the riverbed morphology and scouring and silting in the project area remain stable; the riverbed morphology and scouring and silting in the project area remain basically stable; the riverbed morphology and scouring and silting in the project area change slightly; the riverbed morphology and scouring and silting in the project area change significantly; the riverbed morphology and scouring and silting in the project area undergo major adjustments; 6) A32 Engineering disturbance ratio, the ratio of the disturbed area of ​​the ecological bottom protection project to the total riverbed area of ​​the river section, the weight of this sub-index is 0.08: <20%; 20%-40%; 40%-60%; 60%-80%; 80-100%; 7) A41 Project cost economy, measured from the project cost, the ratio of ecological bottom protection project to traditional bottom protection project, the weight of this sub-index is 0.05: very good, ≤1.0; good, 1.0-1.5; medium, 1.5-2; poor, 2-3; very poor, 3 and above; 8) A42 Project construction difficulty, measured from the construction difficulty, the ratio of ecological bottom protection project to traditional bottom protection project, the weight of this sub-index is 0.05: very good, ≤1.0; good, 1.0-1.5; medium, 1.5-2; poor, 2-3; very difficult, 3 and above; 9) A43 Project Operation and Maintenance Difficulty, the weight of this sub-index is 0.05: simple, basically no maintenance required; good, simple and small amount of maintenance; medium, maintenance required once every 3-5 years; poor, maintenance required once every 1-2 years; complex, requiring continuous maintenance every year; 10) A51 Vertical connectivity, the weight of this sub-index is 0.06: vertical connectivity maintains a natural state, and the structure of the ecological bottom protection does not affect the material exchange between the overlying water and sediment; vertical connectivity is good, and the material exchange between the overlying water and sediment has little impact; vertical connectivity is average, and the material exchange between the overlying water and sediment has a medium impact; vertical connectivity is poor, and the material exchange between the overlying water and sediment is difficult; vertical connectivity is completely blocked, and the overlying water and sediment materials are completely isolated; 11) A52 is conducive to the penetration of aquatic plant roots or the growth of attached organisms. The weight of this sub-indicator is 0.06: the structure and engineering layout of the ecological bottom protection are very conducive to the penetration of aquatic plant roots and the growth of attached organisms; the structure and engineering layout are conducive to the penetration of aquatic plant roots and the growth of attached organisms; the structure and engineering layout are convenient for the penetration of aquatic plant roots and the growth of attached organisms; the structure and engineering layout are not conducive to the penetration of aquatic plant roots and the growth of attached organisms; the structure and engineering layout are extremely unfavorable to the penetration of aquatic plant roots and the growth of attached organisms; 12) A53 Number and density of large benthic animal species, the weight of this sub-index is 0.06: the ratio of the number or density of large benthic animal species in the ecological bottom protection project area to the area without bottom protection is 80% or more; the ratio of the number or density of large benthic animal species in the project area to the area without bottom protection is 60-80%; the ratio of the number or density of large benthic animal species in the project area to the area without bottom protection is 40-60%; the ratio of the number or density of large benthic animal species in the project area to the area without bottom protection is 20-40%; the ratio of the number or density of large benthic animal species in the project area to the area without bottom protection is <20%; 13) A54 is conducive to the creation of diverse habitats and habitats. The weight of this sub-indicator is 0.05: The structure and engineering layout of the ecological bottom protection are very conducive to the creation of diverse habitats and habitats; the structure and engineering layout are conducive to the creation of diverse habitats and habitats; the structure and engineering layout are convenient for biological settlement and habitat; the structure and engineering layout are not conducive to biological settlement and habitat; the structure and engineering layout are extremely unfavorable for biological settlement and habitat; 14) A55 Alien invasive species, the weight of this sub-index is 0.04: no alien invasive species; alien invasive species occasionally appear, but the harm is not great; alien invasive species are relatively common and have not caused harm to the ecological environment; alien invasive species are relatively common, forming stable populations and causing harm to the ecological environment; alien invasive species are dominant, causing serious harm to local species and the ecological environment; The evaluation criteria system for the implementation effect of the inland waterway ecological bottom protection project based on the bottom protection project ecological compliance index ECIR-RBPE includes the bottom protection project ecological compliance index ECIR-RBPE and the evaluation criteria system for the ecological compliance degree of the inland waterway ecological bottom protection project, and the specific contents include: a The calculation method of the ecological compliance index ECIR-RBPE of the bottom protection project is as follows: the weight of each of the 14 sub-items and the obtained score are multiplied and added together to obtain the ecological compliance index of the bottom protection project to be evaluated; b. The evaluation criterion system for the degree of ecological compliance of the inland waterway ecological bottom protection project is as follows: based on the calculated ecological compliance index ECIR-RBPE score of the bottom protection project, the implementation effect of the inland waterway ecological bottom protection project is judged according to the following evaluation criteria: when ECIR-RBPE ≥ 4 points, the evaluation grade is excellent, indicating that the ecological compliance of this type of ecological bottom protection is very high; when 3 points ≤ ECIR-RBPE < 4 points, the evaluation grade is good, indicating that the ecological compliance of this type of ecological bottom protection is relatively good; when 2 points ≤ ECIR-RBPE < 3 points, the evaluation grade is medium, indicating that the ecological compliance of this type of ecological bottom protection is medium; when 1 point ≤ ECIR-RBPE < 2 points, the evaluation grade is poor, indicating that the ecological compliance of this type of ecological bottom protection is relatively poor; when ECIR < 1 point, the evaluation grade is poor, indicating that the ecological compliance of this type of ecological bottom protection is poor.

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