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1.
With the transformation of water conservancy from traditional to eco-hydraulic aiming at sustainable development, the study on eco-efficiency of the water system has attracted a great deal of attention. This study aims to develop a methodology for evaluating the eco-efficiency of water systems of 31 administrative regions in China. Considering the multiple attributes of water systems and a piecewise linear technological frontier, the Rough Set Theory (RST) and Data Envelopment Analysis model (DEA) are combined to analyze the eco-efficiency of water systems. An input-and-output index system is established based on RST. The eco-efficiency for the water system of 31 administrative regions in China is calculated by DEA, and the characteristics of its spatial differences are discussed. The results show that there is a significant difference in the eco-efficiency of water systems: (1) On the whole, the efficiency value of north China is slightly higher than the south; (2) In the eight sub-regions of China, the north coastal area gains the highest efficiency score and the middle reaches of the Yangtze River obtains the lowest value; (3) There are 11 out of 31 regions at the best practice frontier. The spatial difference in eco-efficiency of the water system is a common phenomenon, which reflects the direct or indirect influence by economical, political, legislative, historical, cultural factors and other social development. Based on the above findings, some suggestions are made to improve the eco-efficiency of the water systems in China.  相似文献   

2.
在分析河流生态健康概念的基础上,综合考虑水量、水质、生物状况、水体连通性以及防洪标准等因素,构建河流生态健康评价指标体系和评价等级标准,建立起基于集对分析与可变模糊集的河流生态健康评价新方法。利用该方法对北运河进行实证研究,结果表明,北运河生态处于亚健康状态,需要通过加大治污力度、合理开发利用水量等相关河流生态修复措施使其逐步恢复到健康状态。基于集对分析与可变模糊集的综合评价模型评价结果合理,方法直观简便。  相似文献   

3.
To achieve effective environmental control, it is important to develop methodologies for dealing with uncertainties in model simulation of pollution behaviour and effects. Several procedures have been proposed to quantify uncertainties in modelling studies. This paper utilizes the two methods that are widely applied, i.e. functional analysis and Monte Carlo Simulation.The first-order part of the functional analysis method provides a measure of uncertainties in dependent variables in terms of uncertainties in independent variables. The procedure is based on first-order terms in the Taylor series expansion of the dependent variable about its mean value with respect to one or more independent variables. The major assumption in this procedure is that all independent and dependent variables are the second moment variables (SMV), which means that the behaviour of any SMV is completely described by its mean and standard deviation. The mathematical simplicity of the procedure allows application by simple input-output models. Consequently, it has been applied to many environmental simulators, e.g. hydrological models, stream water quality models, lake water quality models and ground water pollution models.The Monte Carlo Simulation (MCS) method uses a large number of repeated trials or simulations with the values for stochastic inputs or uncertain variables selected at random from their assumed parent probability distributions to establish an expected range of model uncertainty.  相似文献   

4.
WASP模型参数率定与敏感性分析   总被引:3,自引:0,他引:3  
WASP是美国环境保护局提出的水质模型系统,能够用于不同环境污染决策系统中分析和预测各种水质状况.将WASP模型应用于长河水体富营养化分析,采用长河的实际监测数据,对WASP模型做了参数率定与模型验证.得出WASP模型具有易用性,适用于河流水体的富营养化模拟.为确定WASP模型富营养化模拟过程中对模拟结果影响较大的参数,进行了参数灵敏度分析.分析结果表明,影响浮游植物量的最主要参数为20℃浮游植物最大生长速率常数,水中碳源与叶绿素的比值次之.  相似文献   

5.
基于集对分析与可变模糊集的河流生态健康评价模型   总被引:8,自引:2,他引:8  
在分析河流生态健康概念的基础上,综合考虑水量、水质、生物状况、水体连通性以及防洪标准等因素,构建了河流生态健康评价指标体系和评价等级标准,建立起基于集对分析与可变模糊集的河流生态健康评价新方法。利用该方法对北运河进行分析,结果表明,北运河生态处于亚健康状态,需要通过加大治污力度、合理开发利用水量等相关河流生态修复措施使其逐步恢复到健康状态。通过与其它常规方法的比较表明,本文模型评价结果合理,方法直观简便。  相似文献   

6.
Traditionally, water quality modelling has focused on modelling individual water bodies. However, water quality management problems must be analyzed at the basin scale. European Water Framework Directive (WFD) requires introducing physical, chemical and biological aspects into the management of water resources systems. Water quality modelling at a basin scale presents the advantage of incorporating in a dynamic way the relationships between the different elements and water bodies. Currently, there are few tools to deal with water modelling of water quality and management at the basin scale. This paper presents the development of a water quantity model and a water quality model for a very complex water resources system: the Júcar River Basin (Spain). The basin is characterized by a high degree of use of the water and by many water problems related to point and diffuse pollution, on top of a complex water quantity management of the basin. To deal with this problem, SIMGES (water allocation) and GESCAL (water quality) basin scale models have been used. Both are part of the Decision Support System AQUATOOL, one of the main instruments used in Spain in order to analyze water quantity and quality aspects of water resources systems for the compliance with WFD, as shown for the case of study.  相似文献   

7.
根据徒骇河(德州段)历年来水质监测数据及污染源调查结果,经统计分析,确定了水污染类型和相应程度,较全面地揭示了水污染的原因及水污染造成的危害。选用适当的教学模型对未来水质进行预测分析,提出解决水污染的可行性措施。  相似文献   

8.
主成分分析法在温榆河水质评价中的初步应用   总被引:1,自引:0,他引:1  
常规的水质评价方法有很多因不能克服由于涉及因子过多而造成某些重要信息被掩盖的缺陷,而主成分分析法能从众多变量中剔除具有相关性的因子,筛选出主要少数独立综合因子,且这些综合因子能对研究结论做出充分合理的解释。应用主成分分析法,借助Statistical Product and ServiceSocutions(SPSS)软件,对2009年温榆河10个监测断面的7项水质指标进行了分析。通过水质评价综合得分的结果可以看出,在10个监测断面中,丁家坟的污染程度最大。从水质监测数据及其评价结果来看,说明主成分分析结果能真实地反映水质实际情况。  相似文献   

9.
An integrated Rough Set approach is proposed and implemented to discover the historical operating rules of a Sicilian irrigation purpose reservoir. Operating rules are derived by expressing monthly releases from the reservoir as functions of stored volume, inflow and release during a 35-years period. This is accomplished through the Rough Set approach as implemented in the Rose package and the use of some indices able to recognize and further screen out the effective rules used in water supply reservoir management. This approach represents a new mathematical tool quite different to classical fuzzy rule-based systems in the decision rules induction. Results show that the integrated Rough Set approach allows to individuate with acceptable reliability the real criteria used for the system management. Work carried out with equivalent contributions of the Authors. Project AQUATEC “Tecnologie Innovative di Controllo, Trattamento e Manutenzione per la Soluzione dell'Emergenza Acqua” funded by the Italian Ministry of Education, Research and Technological Development (PON 2000–2006).  相似文献   

10.
为了解决普遍意义上的水质模糊识别理论不能评价指标数据超过5级标准值和最大隶属度原则的缺点,本文提出6级水质计算方法来改进模糊模式识别模型。再者,引入Set Pair Analysis(SPA)理论处理等级标准间的不确定性信息。从而构建引入SPA的6级模糊模式识别模型,将其运用于河流实例中。评价结果表明:引入SPA的6级模糊模式识别模型更能准确地确定水质综合等级,为治理河流水质污染提供理论支持。  相似文献   

11.
网箱养鱼对河流型水库水质影响的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
针对网箱养鱼所造成的水污染问题,运用水质模型对网箱养鱼污染进行模拟和预测成为重要的研究课题。提出将网箱养鱼污染概化为面源负荷,采用校准后的QUAL2Kw模型对潘家口水库网箱养鱼污染和网箱撤消后两个方案进行水质模拟和预测,并采用均方根误差法对模型适用性进行评价。同时提出具有绝对负荷量百分比和贡献比例计算模块的QUAL2Kw模型,对不同污染源对出库水质的影响程度进行评价。结果表明:QUAL2Kw模型在潘家口水库的适用性较好;网箱养鱼全部撤消后,潘家口水库的水质状况整体改善的程度不高;为有效改善潘家口水库出库水质,应优先削减潘家口(S6)-潘坝前(S7)的污染物入库负荷量。本文所提出的模型方法及针对出口断面的污染物贡献比例分析可为进一步研究潘家口水库的水环境管理提供科学依据和决策支持。  相似文献   

12.
Diffuse pollution is hard to analyze, control and manage by its nature. Watershed models and Geographical Information Systems (GIS) are recently developed tools that aid analysis of diffuse sources of pollution. However, their applications are not always easy and straightforward. Turkey is a typical example of a mountainous country rich in rivers and streams. Due to the complex geomorphology, land-use and agricultural practices in most of the watersheds in Turkey, modelling, analyzing and managing diffuse pollution has been a challenge. The complex watershed structure forces the modellers to work with spatially high resolution data. Apart from the data, the models themselves may also cause operational problems. These issues and their probable solutions form the basis of the discussions in this paper. It acts as a guideline for modelling and analyzing diffuse pollution by emphasizing the referred problems and difficulties. Design of an Information Technology-based system tool for watershed and/or water quality modelling, which would be suitable for countries having watersheds with similar structure and problems to those of Turkey, is also outlined.  相似文献   

13.
This paper presents the results of the study undertaken at the Tarim River Basin in Northwest China to analyze impacts of flooding on water quality. It was shown that irregular rainfall was the cause of flash floods that affected many ecosystems and eroded soils. Simulation results and the existence of relationships between flood volume and flood peak allowed potential model application that included flood peak estimation. The analysis of water pollution through sample sediment was helped by spectroscopy techniques and it was found that the flood was the main cause of many chemical elements in water. The floods affected the quality of water in the Tarim River where it was slightly basic with pH = 8.1 before flooding and acidic with pH = 6.9 after flooding.  相似文献   

14.
Data-driven models are commonly used in a wide range of disciplines, including environmental engineering. To analyze Omerli Lake’s historic water pollution status, this study monitors data for dissolved oxygen, 5-day biochemical oxygen demand, ammonium nitrogen, nitrite nitrogen, nitrate nitrogen, and ortho phosphate. The quality of the lake water is assessed based on measurements of dissolved oxygen. The collected data are analyzed using regression analysis and artificial neural network models. The main goal of this paper is to reveal the best applicable data-driven model in order to gain forward-looking information regarding the dissolved oxygen level of the lake using other pollution parameters. In order to ascertain eutrophic status, total phosphorus loads for each year are represented on a Vollenweider diagram. Results designate an increasing risk of eutrophication for Omerli Lake in recent years. Results of the data-driven models show that the artificial neural networks model constitutes the best relationship between the dissolved oxygen and other parameters.  相似文献   

15.
The aim of this paper is to develop rules for optimal reservoir operation and water withdrawal from river and aquifer considering water supply and pollution control targets. The general approach is making use of an integrated water quantity-quality management (IWQM) modeling in conjunction with accurate data mining techniques. The IWQM model generates data, including; optimal releases and water withdrawal from river and aquifer for different conditions, and M5P and Support Vector Regression (SVR) data mining models utilize the results of the IWQM model for the derivation of rules. The IWQM model minimizes the deviation from water supply and water quality targets during the planning horizon. This method for derivation of operating rules is applied to a real world case study, Zayandehrood system, in Iran, with serious water supply and water pollution problems. The IWQM model is analyzed for different hydrologic and water demands scenarios with total dissolved solids (TDS) as the water quality indicator. Results show that an integrated approach to reservoir-river-aquifer operation in the study area can reduce the TDS by 43 % in the downstream river.  相似文献   

16.
The ability to predict water quality is a major requirement for planning and execution of developmental projects. It helps entrepreneurs to effectively plan and implement pollution control measures. This study evaluates the ability of different water quality models (statistical; remote sensing; mathematical) to predict salinity in Akkulam–Veli Lake, a tropical lake system. The performance of these three water quality models was evaluated. Prediction of salinity was made accurately with the mathematical model (WASP), compared to the other models. WASP facilitates prediction of daily water quality variations, which is not possible with the other models. A limitation of this model, however, was its ability to predict only a few water quality parameters. The statistical methods are reliable when the number of sampling sites and frequency of sample collection are high, making this method exhaustive and expensive. Remote sensing techniques proved to be less tedious, but are suitable only under specific situations, and not able to produce a high level of accuracy. Nevertheless, this method provides a continuous picture of spatial variations of different water quality parameters to a reasonable level of accuracy. The choice of the ‘best’ model varies on the basis of climatic and field conditions of the lake system of concern. Thus, a combination of water quality models was found to be the most ideal approach for analysing water quality data.  相似文献   

17.
水环境污染系统规划的模糊非线性规划模型   总被引:8,自引:0,他引:8  
本文将模糊集理论与非线性规划优化方法有机地结合起来,首次提出水环境污染系统规划的模糊非线性规划模型.并将它应用于沈阳市南部污水排放系统的最优化处理规划.在满足水质要求的同时,可以显著地降低污水处理的总费用.  相似文献   

18.
As a consequence of the awareness of the pollution impact of storm sewer overflows, managers need tools to evaluate and control stormwaters according to water quality criteria. After an experience of 25 years in storm water quality modelling, very few models are widely and regularly used. According to managers this is due to their cost and their low level of accuracy.The generation and the transport of the pollution in urban systems during a storm event are very complex because they concern many media and many space and time scales. Nevertheless, a typology of the existing models shows that this complexity has been inscribed into the models. This tendency towards complexity makes sewer quality models difficult to put into operation and three main difficulties can be underlined: doubtful mathematical formulation of processes, uncertainties on input and calibration data, difficulties and cost of calibration.Further research is needed to improve the modelling approach and basic knowledge, and we think that a clear distinction should be made between management tools and research models.  相似文献   

19.
汾河水库是万家寨引黄工程的调节水库和山西省最大的地表水饮用水源地,其上游河段的COD和TN有超标现象,故确定库区污染物的输移扩散规律并提出相应的保护措施对保证水库水质安全至关重要。以工程技术资料、DEM模型、遥感及GPS实测信息为基础,采用GIS技术将汾河水库边界和地形进行数字化处理;通过实测数据进行参数率定与模型验证,确定汾河水库的水动力模型和水质模型;将模型进行耦合联用,以汾河水库的水动力为基础,选取COD和TN进行数值模拟,计算污染物在不同进水浓度时库区污染物超标面积,以库区污染物超标面积百分比来表征水库受污染程度。模拟结果表明:风场是影响水库水动力的主要因素;在静风和主导风力作用下污染物分别沿地形和沿下风向堤岸扩散;污染物超标面积百分比与进水污染物浓度限值呈二次函数关系。  相似文献   

20.
排污河道污染特征模拟分析对防治河道污染与合理开发排污河道具有重要意义。针对当前方法存在河道污染特征模拟能耗高的问题,提出基于模糊综合评价法的排污河道污染特征模拟分析,筛选排污河道污染评价指标,建立污染特征模型,根据排污河道水质指标来分析排污河道上下游浓度之间的关系,获取排污河道水质变化趋势的评价标准,分析排污河道污染特征评价因子的重要程度,得到污染特征的综合评价集,计算加权因子并分析排污河道污染特征的模拟变化趋势,以及排污河道污染特征的模拟能耗,最终实现排污河道污染特征的模拟分析。试验结果表明:提出方法在进行排污河道污染特征模拟分析的过程中,模拟能耗在6J以下,产生了较低的模拟能耗;排污河道污染特征模拟结果与实际结果的拟合度最高为90%,验证了提出方法的有效性和可行性,具有较高的实际应用价值。  相似文献   

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