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1.
介绍了引滦入津水系的生态特征、水质问题及发展趋势,在此基础上对引滦入津水源保护的应采取的战略方针及生态恢复技术进行了讨论。提出了从汇水区域生态管理入手,控制水体富营养化,建立流域管理与区域管理相结合的新管理模式,水源保护管理工程实行企业化经营管理方式等建议;以及面源污染防治技术、湿地处理系统的设计与建设等研究内容。  相似文献   

2.
The water quality and eutrophication status of Taihu Lake in recent years are presented and the pollution trends are analyzed. It is shown that because of unreasonable industrial structures, pollution discharge per GDP is high within the Taihu basin, and the pollution discharge from point and non-point sources exceed the basin’s environmental carrying capacity. Especially, excessive pollutants containing nitrogen and phosphorus are being discharged. Moreover, eutrophication may also result from internal pollution sources such as the release of nutrient elements from sediment. All these factors have resulted in the water quality deterioration of Taihu Lake. To solve this environmental problem, possible control strategies are summarized, including the control of internal pollution sources and inflow-river pollution, ecological restoration and reconstruction of the degraded lakeside zone ecosystem, clean water diversion, dredging, and manual algae removal.  相似文献   

3.
Maintaining a natural flow regime helps preserve the health of riverine ecosystems. Conventional studies on reservoir operations have focused mainly on identifying optimal operational schemes for satisfying human water demands. To systematically reflect the ecological effects of both natural and human-induced hydrologic alterations, water diversions downstream of the reservoirs should be considered as well. This research focused on a coupled reservoir operation and water diversion (CROWD) model, created through the integration of a reservoir operation model and a water diversion model. The proposed model considers both human and environmental flow requirements, and represents a compromise that balances ecological protection (preservation of the natural flow regime of a river) and human needs (reduced water shortages). In the reservoir operation model, the reservoir space is divided into three zones and different operating rules are developed for directing reservoir operation when water levels are in different zones; in the water diversion model, different water users are assigned different supply priorities with the instream flows no more than the minimum environmental flows having the highest priority; and the two models are coupled by the water mass balance between the two hydraulic facilities. The non-dominated-sorting genetic algorithm II (NSGA-II) was used to determine the parameters of the developed CROWD model and the model was applied to support the joint operational management of the Tanghe Reservoir and the Liaoyang Diversion in the Tang river basin, China. The resulting reservoir operation and water diversion schemes indicate that the CROWD model is useful for optimizing the operation of reservoirs and water diversion schemes. Moreover, it helps to analyze tradeoffs between human and environmental water needs, resulting in solutions that reduce the risk of water shortages and minimize ecological integrity disturbances.  相似文献   

4.
5.
• Toxicity-oriented water quality monitoring was proposed. • Toxicity-oriented water quality engineering control was proposed. • Future issues to the proposition were discussed. The fundamental goal of water quality engineering is to ensure water safety to humans and the environment. Traditional water quality engineering consists of monitoring, evaluation, and control of key water quality parameters. This approach provides some vital insights into water quality, however, most of these parameters do not account for pollutant mixtures – a reality that terminal water users face, nor do most of these parameters have a direct connection with the human health safety of waters. This puts the real health-specific effects of targeted water pollutant monitoring and engineering control in question. To focus our attention to one of the original goals of water quality engineering – human health and environmental protection, we advocate here the toxicity-oriented water quality monitoring and control. This article presents some of our efforts toward such goal. Specifically, complementary to traditional water quality parameters, we evaluated the water toxicity using high sensitivity toxicological endpoints, and subsequently investigated the performance of some of the water treatment strategies in modulating the water toxicity. Moreover, we implemented the toxicity concept into existing water treatment design theory to facilitate toxicity-oriented water quality control designs. Suggestions for the next steps are also discussed. We hope our work will intrigue water quality scientists and engineers to improve and embrace the mixture water pollutant and toxicological evaluation and engineering control.  相似文献   

6.
The conventional approach to wastewater system design and planning considers each component separately and does not provide the optimum performance of the entire system. However, the growing concern for environmental protection, economic efficiency, and sustainability of urban wastewater systems requires an integrated modeling of subsystems and a synthetic evaluation of multiple objectives. In this study, a multi-objective optimization model of an integrated urban wastewater system was developed. The model encompasses subsystems, such as a sewer system, stormwater management, municipal wastewater treatment, and a wastewater reclamation system. The non-dominated sorting genetic algorithm (NSGA-II) was used to generate a range of system design possibilities to optimize conflicting environmental and economic objectives. Information from a knowledge base, which included rules for generating treatment trains as well as the performance characteristics of commonly used water pollution control measures, was utilized. The trade-off relationships between the objectives, total water pollution loads to the environment, and life cycle costs (which consist of investment as well as operation and maintenance costs), can be illustrated using Pareto charts. The developed model can be used to assist decision makers in the preliminary planning of system structure. A benchmark city was constructed to illustrate the methods of multi-objective controls, highlight cost-effective water pollution control measures, and identify the main pressures on urban water environment.  相似文献   

7.
A model for investigating management alternatives on the Pyramid Lake-Truckee River system of Nevada and California is presented. Cutthroat trout, Cui-ui, Tahoe Sucker and Tui Chub are modeled with special emphasis on river spawning by trout. Management decision variables include hatchery input, water flow control, and diversion screening. Preliminary results indicate that some hatchery input will be needed to support the trout even with the best river management.  相似文献   

8.
Coastal areas commonly consist of an environment of intense economic uses and are thus exposed to conflicts between anthropogenic activities and biodiversity. While several approaches of nature protection have been applied to the terrestrial domain, aquatic biotopes frequently still lack a good ecological state as required by EU policies (WFD and MSFD). For numerous years, the underwater world has been considered as one sphere and was neglected in the development of distinctive concepts of conservation for its variety of biotopes. This paper’s objective is the enhancement of ecological connectivity within the study area through the design of benthic wildlife corridors and a consequent sublittoral biotope network. A step-by-step approach is presented for the optimization of ecological potential in heavily modified coastal water bodies, using Kiel Fjord (Western Baltic Sea) as a case study. The procedure for the development of wildlife corridors includes defining and mapping of existing biotope types, the identification of key species for each biotope type and delineating their mobility range, the reconstruction of near-natural / pre-industrial conditions and deriving the protection priorities by comparing past with current / modified conditions. By harmonizing these scientific insights with the local land use of human society, proposals for biotope restoration and improvements can be made. In Kiel Fjord, compensation measures, obligatory for human interventions, such as construction work in the marine environment in this case, have been implemented and present an opportunity to enhance the connectivity of biotopes, thus creating wildlife corridors for their inhabitants. The composition of benthic wildlife corridors, forming a sublittoral biotope network in accordance with the present anthropogenic uses, holds potential for implementation in comparably altered coastal water bodies and integration into national and international frameworks, in anticipation of its functionality.  相似文献   

9.
New legislation for the protection of inland surface waters, transitional waters, coastal waters and ground waters has recently been established in Italy. This law presents a new integrated approach, where all water bodies are considered as complex ecosystems to be studied in each of their components. The new concept of environmental quality of the water body, based on the ecological and chemical status, is also introduced. At the same time (i.e. the end of 2000), the European Community approved the European Water Framework Directive based on the same basic environmental concepts and criteria of the new Italian law. This paper analyses the important points and innovations required by the new Italian legislation for monitoring and classification of marine coastal waters. Details of definitions, parameters, analysis and monitoring programs are discussed. A comparison with the European Water Framework Directive is eventually given, underlining the specific characteristics of the Mediterranean sea, which have to be taken into consideration when applying the European Directive to this particular ecoregion.  相似文献   

10.
The shores of many Central European lakes located in the hinterland of large conurbations are heavily endangered by intensive settlement, traffic, sewage input, manipulation of the water level, tourism and recreation. This increasing impact has negatively affected the function of the lake shore in respect to conservation and species protection, to water protection and its importance for recreation. This paper describes the overlap of the multiple uses and the precautions planned since 1981 on the national and international level to guarantee the essential multiple functionality, e.g. as drinking water reservoir for the conurbations in the northern part of Baden-Württemberg, as supraregional centre for water sports and tourism, and as an important environment for endangered plant and animal species. Management measures include regional planning as well as the international water protection and preservation with many contributions from non governmental international organisations Given a high agreement concerning these aims, many indispensable actions could successfully be realised on the political and administrative level. On the basis of 14 topics we follow the development since 1981, most recently also driven by the EU (FFH/Natura 2000), Water framework directive). Backlogs became obvious for four topics: 1. The lack of efficient reviews on completed measures, 2. gaps in basic understanding, 3. The dragging harmonisation of an intergrated shore protection program across the borders, and 4. the lack of concepts for a sustainable development including plans for monitoring.  相似文献   

11.
The shores of many Central European lakes located in the hinterland of large conurbations are heavily endangered by intensive settlement, traffic, sewage input, manipulation of the water level, tourism and recreation. This increasing impact has negatively affected the function of the lake shore in respect to conservation and species protection, to water protection and its importance for recreation. This paper describes the overlap of the multiple uses and the precautions planned since 1981 on the national and international level to guarantee the essential multiple functionality, e.g. as drinking water reservoir for the conurbations in the northern part of Baden-Württemberg, as supraregional centre for water sports and tourism, and as an important environment for endangered plant and animal species. Management measures include regional planning as well as the international water protection and preservation with many contributions from non governmental international organisations. Given a high agreement concerning these aims, many indispensable actions could successfully be realised on the political and administrative level. On the basis of 14 topics we follow the development since 1981, most recently also driven by the EU (FFH Natura 2000, Water framework directive). Backlogs became obvious for four topics: 1. The lack of efficient reviews on completed measures, 2. gaps in basic understanding, 3. The dragging harmonisation of an integrated shore protection program across the borders, and 4. the lack of concepts for a sustainable development including plans for monitoring.  相似文献   

12.
Research on lake eutrophication in China began in the early 1970s, and many lakes in China are now known to be in meso-eutrophic status. Lake eutrophication has been showing a rapidly increasing trend since 2000. Investigations show that the main reasons for lake eutrophication include a fragile lake background environment, excessive nutrient loading into lakes, excessive human activities, ecological degeneration, weak environmental protection awareness, and lax lake management. Major mechanisms resulting from lake eutrophication include nutrient recycling imbalance, major changes in water chemistry (pH, oxygen, and carbon), lake ecosystem imbalance, and algal prevalence in lakes. Some concepts for controlling eutrophication should be persistently proposed, including lake catchment control, combination of pollutant source control with ecological restoration, protection of three important aspects (terrestrial ecology, lake coast zone, and submerged plant), and combination of lake management with regulation. Measures to control lake eutrophication should include pollution source control (i.e., optimize industrial structural adjustments in the lake catchment, reduce nitrogen and phosphorus emission amounts, and control endogenous pollution) and lake ecological restoration (i.e. establish a zone-lake buffer region and lakeside zone, protect regional vegetation, utilize hydrophytes in renovation technology); countermeasures for lake management should include implementing water quality management, identifying environmental and lake water goals, legislating and formulating laws and regulations to protect lakes, strengthening publicity and the education of people, increasing public awareness through participation in systems and mechanic innovations, establishing lake region management institutions, and ensuring implementation of governance and management measures.  相似文献   

13.
We employ a three-dimensional coupled hydro-morphodynamic model, the Virtual Flow Simulator (VFS-Geophysics) in its Unsteady Reynolds Averaged Navier–Stokes mode closed with \(k-\omega\) model, to simulate the turbulent flow and sediment transport in large-scale sand and gravel bed waterways under prototype and live-bed conditions. The simulation results are used to carry out systematic numerical experiments to develop design guidelines for rock vane structures. The numerical model is based on the Curvilinear Immersed Boundary approach to simulate flow and sediment transport processes in arbitrarily complex rivers with embedded rock structures. Three validation test cases are conducted to examine the capability of the model in capturing turbulent flow and sediment transport in channels with mobile-bed. Transport of sediment materials is handled using the Exner equation coupled with a transport equation for suspended load. Two representative meandering rivers, with gravel and sand beds, respectively, are selected to serve as the virtual test-bed for developing design guidelines for rock vane structures. The characteristics of these rivers are selected based on available field data. Initially guided by existing design guidelines, we consider numerous arrangements of rock vane structures computationally to identify optimal structure design and placement characteristics for a given river system.  相似文献   

14.
北方城市干涸河流生态环境治理途径   总被引:2,自引:0,他引:2  
以滹沱河石家庄市区段为例,针对目前我国北方城市干涸河流治理和改造存在的问题,提出"以绿代水"的生态恢复与重建模式。在对河流进行生态输水、水资源合理管理与调度的同时,选择适宜的研究尺度,恢复流域内自然植被,实现河道中心区草本滞洪补潜、缓冲区灌木束水导流、杨柳护堤造岸、过渡区林果防风固沙的"绿色滹沱",为北方城市干涸河流的生态环境治理提出新的理念和途径。  相似文献   

15.
污水湿地处理工艺优化组合设计   总被引:8,自引:0,他引:8  
污水湿地处理系统是利用土壤、作物、微生物自然净化功能的生态工程技术。主要有水面湿地和渗滤湿地两种类型,在天津城市污水土地处理与利用系统研究的基础上,将两种工艺的优点进行优化组合,并应用于大港油田等污水湿地处理工程,运行结果表明:将水面湿地和渗滤湿地工艺优化组合设计的示范工程,具有提高水力负荷、减少运行费用、节省工程投资、处理效果稳定等特点,有利于处理工程的长期稳定运行。  相似文献   

16.
天津市水环境保护的战略思考   总被引:2,自引:1,他引:2  
本文从天津市水环境保护的战略出发,系统地论述了水环境保护的目标管理,水环境保护规划,总量和浓度相结合的控制方式,集中与分散相结合的综合治理途径,促进生态平衡的综合性保护措施等一系列管理思路和方法。  相似文献   

17.

Background

The water protection policy of the European Union sits on new footings since the end of 2000: The Water FrameworkDirective (WFD). By replacing, merging and renewing all parts of the European water protection policy from the 1970s, the WFD provides a consistent, transparent and comprehensive concept of what water management should be in the Europe of the coming decades. The new directive is aimed at a holistic approach towards integrated water protection. It sets ambitious high-quality goals to achieve a good status for European lakes and rivers primarily in ecological terms, gives details about the essential processes as well as instruments, and includes everything into a strict time schedule.

Aim

This article adresses progress and shortcomings at the implementation of the WFD in general and with reference to two selected case studies (Rivers Elbe and Upper Danube).

Results and Discussion

After introducing the WFD, its aims and exceptions, a policy summary and background document ‘Environmental objectives und the Water Framework Directive’ and the use of Environmental Quality Standards (EQS) for single ‘priority substances’ as well as ‘hazardous priority components’ is discussed. The initial characterization undertaken by the German states revealed that only about 14% of all surface waters are considered to meet the WFD objectives by the year of 2015. Approximately 60% of the water bodies assessed are at risk of failing the WFD objectives, if not systematic efforts are made to improve the quality. Screenings of sources and paths of exposure for ‘priority substances’ and ‘priority hazardous substances’ according WFD identified one distinct pollution source for surface waters: ‘Historical pollution from sediments’. Because of industrial emissions in the past several river catchment areas are expected to fail the standards demanded by the WFD, due to a risk of remobilization of contaminants from sediments. This holds true for the Rhine river with high loads of hexachlorobenzene (HCB) as well as for Elbe river, where contaminated sediments can be a severe problem. Therefore, integration of sediments into the holistic river basin management approach and their consideration within the ‘programmes of measures’ scheduled for 2009 is highly recommended. At present, a comprehensive weight-of-evidence study verifies whether the observed fish decline at the Upper Danube. River is caused by ecotoxicological hazard potentials of contaminated sediments.

Outlook

Combined investigations of sediment contamination and mobility as well as acute and mechanism specific biotests in effect directed analyses/weight-of-evidence studies show grent potential for the assessment of chemically polluted rivers and should be included into the ‘programmes of measures’ within future management concepts.
  相似文献   

18.
SUMMARY

The notion of sustainable development in the context of water resources is discussed. Facing the increasing pressures — population growth with consequences for settlements and production of food and fibre, and human aspirations to better living standards — the business-as-usual approach to water development and management cannot he globally sustainable. The need for curbing water demands and for ‘doing more with less’ are gaining growing recognition in our increasingly thirsty planet. An integrated approach to freshwater resources is needed, based on the perception of water as a natural resource, part of the ecosystem, and an economic and social good. It is discussed how hydrological extremes jeopardize sustainable development. Sustainability-related properties of drought and flood preparedness and mitigation measures are reviewed. Even if the term ‘sustainable development’ has been typically used in a qualitative sense, in order to compare how different options (e.g. flood protection alternatives) fare with regard to sustainable development, one needs at least rough quantitative measures. A sample of relevant indices is reviewed. It is advocated that hydrological observations should be recognized as an essential component of sustainable development and management of water resources.  相似文献   

19.
Surface water and groundwater always behave in a coupled manner and are major components of hydrologic cycle. However, surface water simulation models and groundwater simulation models are run separately most of the time. Few models focus on the impact of hydraulic changes in the surface water flows on the groundwater, or specifically, the impact of a water transfer project to fill a seasonally dry channel. In this study, a linked surface water and groundwater simulation model was developed to assess the impact of a trans-basin water diversion project on the groundwater. A typical plain area east of Beijing was selected as a case study, representing Beijing’s main source of groundwater used for drinking water. A surface water quality model of the Chaobai River was developed based on the Water Quality Analysis Simulation Program (WASP), and a groundwater model was developed based on the Modular Finite-Difference Groundwater Flow Model (MODFLOW) and the Modular 3-D transport model (MT3D). The results of the surface water simulation were used as input for the groundwater simulation. Water levels and four contaminants (NH3-N, CODMn, F, As) were simulated. With the same initial and boundary conditions, scenario analyses were performed to quantify the impact of different quantities of diversion water on the groundwater environment. The results showed the water quality of the groundwater sources was not significantly affected.  相似文献   

20.
垃圾卫生填埋技术   总被引:22,自引:1,他引:21  
介绍我国第一座现代化城市生活垃圾卫生填埋场-深圳市下坪固体废弃物填埋场的卫生填埋技术设施,如防渗设施、垃圾渗沥液导流设施、场外排水设施和场内清污分流设施等;垃圾卫生填埋工艺技术及作业方法,如分区分层填埋法、单元作业法和高效作业法;垃圾填埋场的环境监测项目及监测成果。  相似文献   

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