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1.
The Danjiangkou reservoir lies in the upper Hanjiang basin and is the source of water for the Middle Route Project (MRP) under the South-to-North Water Transfer Scheme (SNWT) in China. The eco-environment of water resource areas plays an important role in water conservation and purification and would have significant implications for the economic prosperity in Hanjiang basin as well as for the SNWT. Focusing on the Danjiangkou Reservoir Area (DRA), this study established an environmental information system database. Based on the database, an eco-environmental vulnerability assessment method using integrated fuzzy AHP (FAHP) and GIS was developed for the DRA. According to eco-environmental conditions and anthropic effects, vulnerability was classified into five levels: potential, light, medium, heavy and very heavy. The eco-environmental vulnerability distribution and major problems of the eco-environment were analysed and discussed. The results indicated that eco-environmental vulnerability in the DRA was moderate overall. Regions with lower eco-environmental vulnerability were located in Qinling Mountain area in the northwest, Daba Mountain area in the south and the area immediately surrounding Danjiangkou Reservoir in the east. Two regions with very high eco-environmental vulnerability were located in the north of Danjiangkou Reservoir in Henan province and in the western part of Shanxi province. On the basis of analysis of distribution of the different factors of eco-environmental vulnerability, different environmental protection measures were proposed for different areas. This study demonstrated that the proposed method was an effective approach for the assessment of environmental vulnerability. The results gained closely reflected the reality of the eco-environmental vulnerability of the DRA.  相似文献   

2.
Since Turkey is located on a region that is prone to the risks of natural disasters like earthquake, flooding, and avalanche; a majority of the residential areas are facing these risks at various levels. Before determination of these risks, taking action in order to decrease the vulnerability levels of the residential areas will help keep the damage at the minimum level in case of a disaster. Urban planning decisions which are made in accordance with vulnerability studies aiming to determine natural disaster risks will not only help prevent loss of life but also help decrease negative social and economic effects of disasters. The Zonguldak city has been chosen as a case study area since Zonguldak metropolitan area has endured almost all kinds of threats that a city can face. In this study disaster-producing factors in the area are primarily considered which can be named as topography, destruction of forest lands, geological and karstic structure, mining activities, and misuse of the land, and later risk assessment is conducted with geographic information system (GIS). It has been assessed that more than half of the buildings within the study area were constructed in areas not suitable for housing. It is concluded that there is a need for urgent urban development plan for the city.  相似文献   

3.
The Coastal Vulnerability and Exposure Degree (CVED) of the Gran Canaria Island and the coastal risk of Playa de Las Canteras (Las Palmas de G.C.) have been assessed by means of a GIS analysis. The evaluation of coastal vulnerability (H) has been performed by using two different levels of analysis: the first one regarding the entire Island (Coastal Vulnerability Index method - CVI), the second one regarding specifically Las Canteras Beach, selected for its socio-economic importance (Coastal Vulnerability Assessment method - CVA). The application of the CVI method, based on geologic-geomorphologic and meteomarine data easily available, has allowed the regional scale assessment of coastal vulnerability (H) along the Gran Canaria coastline and, therefore, the individuation of more critical coast stretches deserving further analysis. The application of the CVA method, based on more specific morphologic-sedimentary beach features that allow to consider both the beach retreat due to storm surge and the coastal inundation due to run-up on the beach, has provided a large scale detail on the coastal vulnerability of Las Canteras Beach. Socio-economic and damage indexes have been determined for the 15 coastal municipalities included in the study area and, by means of the resulting matrix product, the degree of exposure (Ex) along the Gran Canaria coast has been assessed. Finally, the combination of coastal vulnerability and exposure levels has allowed to obtain the Coastal Vulnerability and Exposure Degree (CVED) for the entire Island and the risk levels that characterize specifically Las Canteras Beach. Major results in terms of CVED highlight prevailing low vulnerability and exposure levels along the western coast, and overall high vulnerability and exposure levels along the eastern coast, from Las Palmas de G.C. to San Bartolomé de Tirajana. The focus made on Playa de Las Canteras has allowed to identify the areas characterized by medium and high risk levels that represent approximately one third (940 m) of the entire beach and are located in its central part. The used two-level analysis approach has proved its efficiency by highlighting the degree of coastal vulnerability along the study coast and, especially, more critical coast stretches (CVI method) such as the Playa de Las Canteras that can be successfully analysed with the CVA approach allowing for a large-scale assessment of risk aspects, essential for a correct definition of priority management strategies. Results obtained with the present study, along with the awareness of the increasing phenomena of coastal erosion and marine flooding arising on the mid-long term due to the effects of global climate change, highlight the need for the competent public administrations of Gran Canaria to develop a strategic approach to coastal management and sustainable development that considers as a whole socio-economic values and natural resources, coastal vulnerability and exposure degree, and risk aspects.  相似文献   

4.
运用压力-状态-响应模型和层次分析法构建生态安全评价指标体系,综合运用GIS技术及模糊物元分析方法对南京市仙林新市区建设前后(2003和2007年)的生态安全状况进行评价。结果表明,2003—2007年,仙林生态安全状况主要向2个方向发展,生态安全和不安全区域面积均有所增加,占区域总面积比例分别由9.6%和12.9%增加至22.3%和15.0%。由于各区域发展模式不同,生态安全状况区域差异明显。具体表现为仙鹤片区与白象片区生态安全区域面积明显增加,占研究区总面积比例分别由2.6%和3.9%增加至10.1%和9.3%;麒麟片区生态安全状况以临界安全为主,部分片区由临界安全状态向较安全状态转化;青龙片区生态安全状况变化不大。  相似文献   

5.
This contribution determines the coastal erosion risk of Necochea and Quequén cities, Necochea Municipality, Buenos Aires Province (Argentina). Both risk components, hazard and vulnerability, were assessed by the construction of indices. The hazard index is composed of four indicators: the erosion or accretion rate, coastal geomorphology, storm waves effects, and sediment supply. The vulnerability index is comprised of land use/cover, demographic, life conditions, and work and consumption indicators, and includes population census data such as demographic, education, health, sanitary, economic, production, work and population exposure aspects. The analysis concluded that coastal erosion risk ranges from very low to high along the study area, Quequén yielding the highest values. Risk levels vary in both cities based on the uneven spatial distribution of hazard. The risk assessment developed herein constitutes a practical and adequate tool that can be utilized with other elements and tasks in the elaboration of a coastal management program.  相似文献   

6.
In this paper, it proposed an index system for hazard and vulnerability evaluations of water distribution networks, based on the simulation of contamination events caused by pollutant injections at different junctions. It attempted to answer the following two questions in the case of contamination events: 1) Which are the most hazardous junctions? 2) Which are the most vulnerable junctions? With EPANET toolkit, it simulated the propagation of the contaminant, and calculated the peak concentration of the contaminant and mass delivered at different nodes. According to types of consumers, different weights were assigned to the consumer nodes for assessing the influence of the contaminant on the consumers. Using the method proposed herein, both the hazard index and vulnerability index were calculated for each node in the pipe network. The presented method was therefore applied to the water network of the city of Zhenjiang, which contains two water plants, two booster pump stations with storage tanks. In conclusion, the response time, the relationships between the peak concentration of contaminant and the total absorption are the most important factors in hazard and vulnerability evaluation of the water distribution network.  相似文献   

7.
A self-developed sewer health assessment system using the fuzzy comprehensive evaluation and analytical hierarchy process was applied to give a comprehensive health condition evaluation on part of the local sewers in a southern Chinese city based on the sewer video data collected by a sewer inspection closed circuit television (CCTV) robot. Aside from the overall condition evaluation, the structure, function, and stability status of the sewer were also analyzed using the method. A comprehensive index H was proposed to give the overall health condition of pipes with different defects, and Ht, Hs, and If were used to quantify the defects affecting the tightness, stability, and function of the pipe, respectively. Results show that 48% of the inspected pipes were in good condition (0〈H〈0.25), and about 33% of the sewer pipes analyzed were categorized to be at severe or urgent condition levels (H 〉 0.5), although most of the pipes were installed only within five years. Frequent sedimentation affects the function of the sewer, and deformation and joint damage affect the structure of the sewer.  相似文献   

8.
基于主成分分析的中国南方干旱脆弱性评价   总被引:2,自引:0,他引:2  
王莺  ;王静  ;姚玉璧  ;王劲松 《生态环境》2014,(12):1897-1904
干旱脆弱性是干旱灾害形成的根本原因。遵循全面性、系统性和可操作性原则,选取水资源脆弱性、经济脆弱性、社会脆弱性、农业脆弱性和防旱抗旱能力脆弱性5个准则层,共32个指标,建立了中国南方农业干旱脆弱性评价指标体系,运用主成分分析的理论方法确定评价指标权重,建立中国南方地区的干旱脆弱性评价模型,得到不同省市的干旱脆弱性指数、分级阈值和区划,以期为南方地区防旱减灾工作提供基础数据和理论支持。得出以下结论,(1)通过主成分分析法得到四个主成分,第一主成分方差贡献率为54.90%,主要反映农业脆弱性和社会脆弱性;第二主成分方差贡献率为23.64%,主要反映水资源脆弱性和经济脆弱性;第三主成分和第四主成分所占比重较小,主要反映防旱抗旱能力脆弱性。(2)以4个主成分的方差贡献率为系数建立南方干旱脆弱性评价模型,得到中国南方干旱脆弱性综合评价得分及其排名,其中水资源脆弱性由高到低依次为云南、广西、贵州、四川、重庆和广东;经济脆弱性由高到低依次为广西、云南、贵州、四川、重庆和广东;社会脆弱性由高到低依次为贵州、云南、广西、重庆、四川和广东;农业脆弱性从高到低依次为贵州、云南、广西、重庆、四川和广东;防旱抗旱能力脆弱性由高到低分别为云南、贵州、四川、广西、重庆和广东;干旱脆弱性综合评价由高到低依次为云南、贵州、广西、四川、重庆和广东。(3)对干旱脆弱性指数进行正态分布性检验,发现该指数基本服从正态分布。根据正态分布原理,得到干旱脆弱性分级阈值,将干旱脆弱性指数小于0.3842定义为低风险,大于1.0758定义为高风险,介于两者之间的定义为中等风险,获得干旱脆弱性分级区划图。广东省位于干旱的低脆弱区,四川和?  相似文献   

9.
A growing awareness of increasing trends in coastal erosion and flooding due to climate change is triggering a demand for the rapid assessment of the potential responses of the coastlines around the world, principally in locations where human occupation is especially endangered. Investigations of present and future physical vulnerability and associated social risk have, therefore, become crucial for coastal management. In order to provide a quick and simple methodology for the identification of vulnerable coastal segments, Sharples (2006) has proposed a mapping methodology, called the smartline approach, which consists of representing, by means of simple lines, a geomorphic classification of the hinterland, backshore and beaches. The aim of this paper is to apply the smartline approach to coastal vulnerability assessment with inclusion of social data. The results show that this methodology is appropriate for the indication of coastal segments with varying degrees of vulnerability to erosion and flooding and for the appraisal of the resulting social risk.  相似文献   

10.
Effective ecosystem‐based management requires understanding ecosystem responses to multiple human threats, rather than focusing on single threats. To understand ecosystem responses to anthropogenic threats holistically, it is necessary to know how threats affect different components within ecosystems and ultimately alter ecosystem functioning. We used a case study of a Mediterranean seagrass (Posidonia oceanica) food web and expert knowledge elicitation in an application of the initial steps of a framework for assessment of cumulative human impacts on food webs. We produced a conceptual seagrass food web model, determined the main trophic relationships, identified the main threats to the food web components, and assessed the components’ vulnerability to those threats. Some threats had high (e.g., coastal infrastructure) or low impacts (e.g., agricultural runoff) on all food web components, whereas others (e.g., introduced carnivores) had very different impacts on each component. Partitioning the ecosystem into its components enabled us to identify threats previously overlooked and to reevaluate the importance of threats commonly perceived as major. By incorporating this understanding of system vulnerability with data on changes in the state of each threat (e.g., decreasing domestic pollution and increasing fishing) into a food web model, managers may be better able to estimate and predict cumulative human impacts on ecosystems and to prioritize conservation actions.  相似文献   

11.
This study deals with fuzzy rule based modelling of nitrogen (N)-leaching from arable land. Main purpose is the elaboration of a method, which allows dynamical regionalisation of results from process-based models for large regions and can be efficiently included in metamodels or decision support systems for rapid integrated assessment of water resources. The paper is the second part of a two-part paper. In the first paper the distributed ecohydrological model SWIM had been applied to calculate and analyse nitrogen dynamics in arable soils for a set of representative natural and management conditions in the Saale River basin (Ecol. Model. (in press)). Here, in the second paper the results from those simulation experiments are used to define, train and validate fuzzy rule systems for the estimation of N-leaching. Nine fuzzy rule systems, specific for nine soil classes, were created from the simulation experiments, representing the conditions for the whole Saale River basin. The fuzzy rule systems operate on monthly time steps and consist of 15 rules and seven input variables each, which are compiled from time series of precipitation, percolation and evapotranspiration as well as from information about fertilizer and crop specific nitrogen uptake. Simulated annealing as a non-linear discrete optimisation method is used for automatic rule assessment. Validation of the fuzzy rule systems, carried out by split sampling of 30-year simulation period, shows satisfactory performance on an annual basis and good performance on the long-term basis with average correlation between SWIM-simulated and fuzzy rule-estimated N-leaching values of 0.78 and 0.94, respectively.  相似文献   

12.
The aim of the present study is to assess the present geo-environmental hazards, both flash flooding and seismic activity in the western part of Gulf of Suez. Assessment includes the analysis of satellite images, topographical, geological and other ancillary geological data using GIS technology. GIS data integration and analysis, including morphometric, local seismic activity and structural data analysis indicated that the area is under threat from two types of geo-hazards. Morphometric analysis strongly supported the high probability of flash flooding in different sites within the study area. The structural lineaments, extracted from an enhanced ETM+7 image, showed that the majority of seismic activity is related to segments of the fault system of the Gulf of Suez and the Gulf of Aqaba. The seismic activity hazard was taken into consideration through the identification of the sources of events. Seismic activity in the study area markedly increases from north to south. The distribution of the seismic activity pattern and data analysis for the study area clearly exhibits the urgent need for an assessment and rehabilitation program to mitigate geo-hazard along the existing structures.  相似文献   

13.
In recent years, the urban drainage system in China is facing the dual pressure of renovation and construction. This requires that the integrated assessment for the planning and operation of the urban drainage system is obligatory. To evaluate the urban drainage system, an integrated assessment methodology based on the analytic hierarchy process (AHP), integrated simulation, and fuzzy assessment is established. This method is a multi-criteria decision adding app roach to the assessment of the urban drainage system comprehensively. Through the integration of the Storm Water Management Model (SWMM), a simple wastewater treatment plant model, and a surface water quality model, an integrated modelling system for the urban drainage system is developed and applied as a key tool for assessment. Using the established method, a case study in Shenzhen City has been implemented to evaluate and compare two urban drainage system reno vation plans, the distributed plan and the centralized plan. Because of the particularity of this case study, the established method is not applied entirely. Considering the water environ mental impact, ecological impact, technological feasibility, and economic cost, the integrated performance of the distri buted plan is better. As shown in this case study, the proposed method is found to be both effective and practical.  相似文献   

14.
Abstract:  The ability to predict which areas of conservation importance are most vulnerable to transformation and to rank the relative damage that transforming land uses could cause to biodiversity are important components of an effective and realistic conservation planning process. We used the South African grassland biome as a case study to illustrate the assessment of vulnerability to land-use transformation through the construction of a "threat map." We identified the dominant transforming land uses and created suitability models based on area appropriateness for each. Land uses were scored according to their expected relative impacts on biodiversity, with a framework that included compositional, structural, and functional components. This information, once combined, resulted in a map that highlighted the areas most vulnerable to transformation in terms of the likelihood of their transformation and the impact on their biodiversity. We propose that such an analysis of the threat of transformation, in combination with species-representation approaches, will aid the integration of conservation planning theory and decision making. This approach can be applied at any scale and in any region with a robustness and accuracy dependent on data quality, resultant suitability models, and comprehension of how land uses affect an area's biodiversity.  相似文献   

15.
Understanding risks from the human-mediated spread of non-indigenous species (NIS) is a critical component of marine biosecurity management programmes. Recreational boating is well-recognised as a NIS pathway, especially at a regional scale. Assessment of risks from this pathway is therefore desirable for coastal environments where recreational boating occurs. However, formal or quantitative risk assessment for the recreational vessel pathway is often hampered by lack of data, hence often relies on expert opinion. The use of expert opinion itself is sometimes limited by its inherent vagueness, which can be an important source of uncertainty that reduces the validity and applicability of the assessment. Fuzzy logic, specifically interval type-2 fuzzy logic, is able to model and propagate this type of uncertainty, and is a useful technique in risk assessment where expert opinion is relied upon. The present paper describes the implementation of a NIS fuzzy expert system (FES) for assessing the risk of invasion in marine environments via recreational vessels. The FES was based on expert opinion gathered through systematic elicitation exercises, designed to acknowledge important uncertainty sources (e.g., underspecificity and ambiguity). The FES, using interval type-2 fuzzy logic, calculated an invasion risk value (integrating NIS infection and detection probabilities) for a range of invasion scenarios. These scenarios were defined by all possible combinations of two vessel types (moored and trailered), five vessel components (hull, deck, internal spaces, anchor, fishing gear), two infection modes (fouling, water/sediment retention) and six frequently visited marine habitats (marina, mooring, farm, ramp, wharf, anchorage). Although invasion risk values determined using the FES approach was scenario-specific, general patterns were identified. Moored vessels consistently showed higher invasion risk values than trailered vessels. Invasion risk values were higher for anchorages, moorings and wharves. Similarly, hull-fouling was revealed as the highest infection risk mode after pooling results across all habitats. The NIS fuzzy expert system presented here appears as a valuable prioritising and decision-making tool for NIS research, prevention and control activities. Its easy implementation and wide applicability should encourage the development and application of this type of system as an integral part of biosecurity, and other environmental management plans.  相似文献   

16.
绿地是城市人工景观中最重要的自然要素,以往对绿地景观生态的研究主要集中在能量流动和空间结构等方面,很少涉及城市绿地景观生态的综合评价。本文利用融模糊综合评判和模糊聚类分析于一体的模糊综合法对城市绿地系统景观生态进行了综合评价。  相似文献   

17.
A hydraulic model-based emergency scheduling Decision Support System (DSS) is designed to eliminate the impact of sudden contamination incidents occurring upstream in raw water supply systems with multiple sources. The DSS consists of four functional modules, including water quality prediction, system safety assessment, emergency strategy inference and scheduling optimization. The work flow of the DSS is as follows. First, the water quality variations on specific cross-sections are calculated given the pollution information. Next, a comprehensive evaluation on the safety of the current system is conducted using the outputs in the first module. This will assist in the assessment of whether the system is in danger of failure, taking both the impact of pollution and system capacity into account. If there is a severe impact of contamination on the reliability of the system, a fuzzy logic based inference module is employed to generate reasonable strategies including technical measures. Otherwise, a Genetic Algorithm (GA)-based optimization model will be used to find the least-cost scheduling plan. The proposed DSS has been applied to a coastal city in South China during a saline tide period as validation. Through scenario analysis, it is demonstrated that this DSS tool is instrumental in emergency scheduling for the water company to quickly and effectively respond to sudden contamination incidents.  相似文献   

18.
城市绿地综合效益评价方法探讨:——天津实例应用   总被引:14,自引:0,他引:14  
本文从复合生态系统理论出发,建立了城市绿地综合效益评价指标体系并将AHP决策分析方法同模糊评价方法相结合,提出了一种城市绿地综合效益评价方法,同时,阐述了这一方法在天津的实际应用。  相似文献   

19.
区域生态安全:概念及评价理论基础   总被引:15,自引:3,他引:15  
借鉴国内外的研究成果,提出区域生态安全的概念是指在一定时空范围内,在自然及人类活动的干扰下,区域内生态环境条件以及所面临的生态环境问题不对人类生存和持续发展构成威胁,并且自然-经济-社会复合生态系统的脆弱性能够不断得到改善的状态。指出生态安全评价是一个多学科交叉的研究领域,其评价理论基础涉及可持续发展理论、生态系统服务功能理论、生态承载力理论、时空论和系统工程论等;生态安全是可持续发展的基础,两者具有内涵和目标的一致性;区域生态安全研究的目的就是平衡人类的自然资源利用与生存环境质量需求的矛盾,保证生态系统在持续安全的状态下提供服务;应用生态承载力的研究成果有助于补充和完善生态安全评价。区域生态安全评价强调研究对象的时空性和研究方法的系统性。多学科整合能更好地指导区域生态安全评价。  相似文献   

20.
Vulnerability assessment is one of the methods currently being used to measure the ocean and coastal sustainability in order to enable better evaluation and redesign of land-based development and policy-making. Because of different geological and geographical formations, the elements that comprise the vulnerability indicators are different from each other, and there are various vulnerability equations that have been used. At the present time, there are no unified vulnerability indicators that can be applied universally to every country. The Seribu Islands, Indonesia, also known in English as the Thousand Islands, consisting of 105 islands located to the north of Jakarta, have been chosen as a study area for vulnerability assessment according to the basic principles of Integrated Coastal Zone Management theory. The results indicate that in practice, Indonesian Integrated Coastal Zone Management legal systems do exist and that in some cases, part of the responsibility for the problems rests with legislation that imposes complex systems of administration, unrealistic sanctions and impractical solutions. This research also shows that inter-sectoral, inter-governance and spatial developments are the three components that need to be improved for the successful implementation of Integrated Coastal Zone Management in the region.  相似文献   

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