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1.
    
A one‐dimensional hydrodynamic reservoir model is coupled with a stochastic fish population model to examine the impacts of cold water pollution (CWP) on the Australian freshwater fish, Murray cod, downstream of Hume Dam, Australia. Mitigation of CWP through the introduction of selective withdrawal capabilities to access near‐surface water is predicted to increase discharge temperatures during the crucial spring‐early summer post‐spawning period by 4–6°C for normal operating conditions, that is, a full reservoir in early spring. No improvement in discharge temperature was predicted for drought conditions characterized by relatively low storage levels in early spring. The predicted temperature increase using selective withdrawal increased the predicted average minimum female population abundance by 30–300% depending on the assumed spawning behaviour. Increased discharge temperatures appear to be achievable and are expected to reduce the stress currently impacting Murray cod populations due to CWP during crucial post‐spawning periods. This provides evidence that mitigation of this problem may assist in rehabilitating Murray cod populations in the Murray River downstream of Hume Dam. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

2.
    
Cyanobacterial blooms present significant water quality problems worldwide. Flow management is considered to be one of the most promising approaches for combating the cyanobacterial bloom problem in rivers. In this paper, a new method for evaluating the effectiveness of flow management strategies in reducing the risk of cyanobacterial blooms is developed and applied to the River Murray at Morgan, South Australia. As stratification has been shown to be a necessary condition for significant growth of certain cyanobacteria species, the method uses estimates of the probability that stratification events of various durations will occur in conjunction with estimates of population growth during stratified conditions to determine the probability that blooms of various magnitudes will occur. The results of the case study indicate that the probability that blooms of the cyanobacterium Anabaena circinalis exceeding 15 000 cells/ml will occur in any given year under summer entitlement flow conditions is 11.7%, which is in excellent agreement with results obtained using a Poisson–Bayesian approach applied to 17 years of historical data of cell densities of Anabaena circinalis at the study site. The results obtained also indicate that increasing inflows into South Australia by 10 000 Ml/day, which is the maximum achievable increase given current operational constraints, would not have a significant impact on the occurrence of blooms exceeding 15 000 cells/ml. An additional flow of 19 900 Ml/day into South Australia would be required to reduce the probability of occurrence of blooms exceeding 15 000 cells/ml to 0.01%. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

3.
水资源系统的风险管理成为水资源可持续利用的必然要求,对复杂的水资源系统所面临的各种各样的风险进行分析越来越成为热点。现对风险的一般概念进行讨论,并在此基础上介绍水资源系统风险的定义;水资源系统风险管理过程包括定义系统问题、风险识别、风险分析(风险估算和评价)、风险处理和风险决策;重点对风险分析的数学模型进行了综述。  相似文献   

4.
在考虑污染场地水文地质参数的空间变异性以及浓度随时间变化的基础上,构建了污染场地健康风险动态评价模型。通过灵敏度分析选取空间变异对数值模拟影响较大的随机参数,运用地下水模拟系统(Groundwater Modeling System,GMS)中的蒙特卡罗随机模拟得到敏感点污染物任意时刻的概率浓度分布特征,进而选取50%和95%分位点分别代表正常情况和最不利情况,预测敏感点健康风险历时变化特征。以石家庄市藁城区某铬化工污染场地为案例进行分析,结果表明,敏感点初始时健康风险值为0.81,在可以接受的风险范围内,污染羽运移1a后,在正常情况和最不利情况下,风险值分别为1.28、1.52,均大于1,即存在非致癌风险,随后逐渐增大,正常情况下,直到第13年才达到风险可接受水平,说明敏感点未来一段时间都存在较大的健康风险,因此需要对污染场地地下水进行修复。  相似文献   

5.
以洪水风险调度理论为研究基础,针对汛限水位变幅前后导致水库防洪系统风险变化,构建一套较完善的汛限水位变幅控制风险分析体系,体系包括水库系统风险分析方法、风险计算模型及实施原则。笔者通过实例运用,分析具体水库汛限水位变幅前后的防洪目标风险率增量,为水库风险分析提供了可靠的参考依据。  相似文献   

6.
    
The Murray–Darling river system is highly regulated and is Australia's major surface water resource. It is subject to blooms of the toxic cyanobacterium Anabaena circinalis, which present significant water quality problems. As a result of these blooms, an algal management strategy has been developed for the Murray–Darling basin. One of the major objectives of the strategy is the development of flow management strategies for key reaches of the river system. Intensive studies in the Murrumbidgee River, Australia, have indicated that persistent thermal stratification is a requirement for blooms of this cyanobacterium to occur. In the lower Murray, mean wind speed was found to be the major factor affecting the degree of thermal stratification under low flow conditions, which generally exist during the months of December to March. In this paper, the effect of various flow management scenarios on the likelihood of the occurrence of blooms in the River Murray at Morgan, South Australia, are assessed. A frequency analysis is carried out on 30 years of wind speed data to determine the probability of occurrence of persistent thermal stratification under a number of flow regimes. The scenarios evaluated include existing base flow conditions, altered base flow regimes, temporary releases from an upstream storage (Lake Victoria) and the temporary reduction of weir pool levels. The results obtained indicate that the dispersal of existing blooms by simultaneously reducing the weir pool levels at Locks 1–3 is the most effective and economical strategy for combating bloom formation by A. circinalis in the River Murray at Morgan. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

7.
基于最大龙口流速指标的立堵截流施工风险随机模拟研究   总被引:3,自引:2,他引:1  
截流系统受到水文水力等随机因素的影响,因此,设计的截流方案的风险如何是需要全面考虑的。本文从截流系统的风险认识入手,确定出能够反映截流系统风险的系统量,在理论分析的基础上,提出采用随机模拟计算方法来计算既考虑水文不确定性又考虑水力不确定性的截流系统风险计算方法,实例验证该方法的可行性。从而可以为截流系统的方案设计与比较起到辅助决策作用。  相似文献   

8.
本文介绍了污染风险管理的两个主要方面:鉴定和减少潜在和现有风险(预防管理),对已发生事故进行处理(应对管理)。预防管理包括对水域内潜在污染因子的鉴定以及评定如何使风险降到最低,应对管理指通过政策法规和实际行动,根据发生事故的严重程度采取相应措施,并以尼尔基水库为例加以说明。  相似文献   

9.
Risk-Based Decision Analysis in the Design of Water Supply Projects   总被引:1,自引:0,他引:1  
The application of a decision analysis methodology to a small-scale water-supply/aquifer-contamination problem is presented. The main characteristic of the study is the development of a series of alternative strategies to ensure a continuous water supply to a village under variable risk conditions. It is assumed that the risks involved in the analysis reflect the uncertainty as to the hydraulic conductivity. Thus, a stochastic simulation model for groundwater flow and contaminant transport is employed in order to evaluate the implications of uncertainty in the system's behaviour upon the overall design decisions. Alternative decision strategies are formulated by considering both actual and probabilistic costs, and they are finally compared using a risk–cost–benefit objective function.  相似文献   

10.
    
Water and natural resource managers are concerned with evaluating how fish habitat and populations may respond to water diversions and small‐scale flow augmentations. We used two‐dimensional hydraulic models, habitat suitability curves and an individual‐based population viability model to assess whether flow augmentations of about 0.28–0.57 m3/s would create suitable habitat for federally listed native fish loach minnow Rhinichthys cobitis and spikedace Meda fulgida in a reach of the Gila River, New Mexico, and then examined how fish population viability may change under a variety of colonization and extinction scenarios. These simulations help to inform water management decisions in a reach of the Gila River where river diversions currently exist and new diversions and augmentations are being proposed. Our results suggest that the flow augmentations evaluated will result in small changes (on average across life stages, ?0.22% to 4.06%) in suitable habitat for loach minnow and spikedace depending on augmentation scenario and fish life stage. While these percent changes are small, they would result in a reduction in the dewatering of the river channel in a river reach where native fish abundance is thought to be low. Actual native fish responses to these habitat changes are unknown; however, these flow augmentations could potentially allow these native species to re‐colonize this river segment from upstream or downstream sources increasing species distribution and likely population viability. Maintaining viable populations of native fish in this river reach is dependent on complex factors including persistence of suitable habitat for multiple life stages, connectivity with other populations and minimizing risk of invasion from non‐native species. We recommend that these predictions from the habitat and population models be tested and verified in an adaptive management framework linking modelling, experimental management, monitoring and reassessment to inform water management decisions in the Gila River. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

11.
Hussein A. Amery 《国际水》2013,38(4):481-489
Abstract

Islam offers its followers extensive guidelines on all aspects of life including how they should use and manage the natural environment. This religion's teachings on matters related to, for example, family affairs and inheritance are well developed and widely applied in the Islamic World. However, the hydrological dimensions of Islam are underdeveloped. This paper is a small step towards the development of Islamically-inspired water management principles. It illustrates that the Koran and hadith have relatively elaborate strategies for water conservation and pollution-prevention. The rationale that water management policies need to fit the cultural norms of the affected people guided the approach to this paper. It hence argues that a carefully-calibrated, Islamically-grounded water management policy is likely to lead to wider acceptability and broader compliance by Muslims because it reflects their value system.  相似文献   

12.
洪水灾害风险管理的理论框架探讨   总被引:9,自引:0,他引:9  
洪水灾害管理是一项复杂的系统工程,在防洪减灾工程理论与实践中具有重要意义。根据洪水灾害风险的形成机制,提出并系统地阐述了由洪水灾害危险性,洪水灾害易损性和洪水灾害灾情组成的洪水灾害风险结构,在该风险结构基础上把洪水灾害风险管理的理论框架进一步展开为洪水灾害危险性分析,洪水灾害易损性分析,洪水灾害灾情分析和洪水灾害风险决策分析4个具有相互联系的部分。  相似文献   

13.
在新的世纪中,我国将迎来水电开发建设新的重要发展时期,一批高坝正要或将要开工建设。这些高坝若发生破坏,除工程破坏本身引起的经济损失外,其次生灾害带来的后果极其严重。推进高坝风险的定量分析是坝工建设本身迫切需要解决的问题。因此,在高坝建设中引入风险理论,结合工程可靠性分析进行高坝可靠度风险分析具有重要的工程和社会实践意义。其基本研究思路应以重大水电工程实践为背景,以可靠度理论、随机力学、风险分析理论为基础,进行大坝风险分析的交叉科学研究,需采用现场实测资料,社会调查,力学数值模拟相结合的技术路线。其主要步骤应以风险分析的四级结构展开,包括大坝系统组成形式研究、主要风险因子对大坝系统安全影响的研究、关键单元可靠度研究、大坝体系可靠度研究、大坝系统风险分析研究、安全保障关键技术研究等。  相似文献   

14.
水利工程投标阶段主要风险包括经济风险、设备和材料采购风险、合同风险、自然与环境风险等,在工程投标过程中要有针对性地依据本企业自身情况及所投标项目的特点进行风险分析,采取相应的预控措施,为工程中标后的经营管理奠定良好的基础。本文对此加以介绍。  相似文献   

15.
我国农业干旱风险研究进展简述   总被引:1,自引:0,他引:1  
主要综述了农业干旱及其风险的内涵,从农业干旱风险分析、风险评估、风险管理3方面系统阐述了农业干旱风险的研究机理.建立了理论框架;归纳总结了农业干旱风险指标体系、风险分析模型等研究方法.农业干旱风险研究方法应用方面主要是针对农业干旱风险管理及对策来达到防灾减灾的目的,为制定防灾减灾决策提供科学合理的依据;最后总结了我国在...  相似文献   

16.
我国农业干旱风险研究进展简述   总被引:1,自引:0,他引:1  
主要综述了农业干旱及其风险的内涵,从农业干旱风险分析、风险评估、风险管理3方面系统阐述了农业干旱风险的研究机理,建立了理论框架;归纳总结了农业干旱风险指标体系、风险分析模型等研究方法。农业干旱风险研究方法应用方面主要是针对农业干旱风险管理及对策来达到防灾减灾的目的,为制定防灾减灾决策提供科学合理的依据;最后总结了我国在这方面的研究历程,简述了各阶段的突出贡献。  相似文献   

17.
蒙特卡洛随机模拟法在水电工程风险分析中的应用   总被引:6,自引:0,他引:6  
蒙特卡洛随机模拟法是水电工程经济评价风险分析中的一种重要方法,本文以实例介绍了此方法在水电工程的具林应用,并取得了较好的效果。  相似文献   

18.
在综合分析我国城市饮用水水源现有状况下,阐述如何开展城市饮用水水源地风险评价和管理风险评估、风险减免和规避、全过程风险监控和信息发布以及事故应对的工作内容。建议:1开展全国城市饮用水水源地风险评估和风险管理工作;2城市饮用水水源风险管理要以流域环境应急管理相衔接;3强化政府的监管及公共服务职能;4探索水源地保护与补偿机制。提出对于高风险的城市供水水源地难以降低风险的,必要情况下要改变水源,选择风险相对低的水源地作为供水水源。  相似文献   

19.
松花江流域水污染特征及其调控对策   总被引:3,自引:0,他引:3  
针对松花江流域日益突出的水问题,研究总结了流域水污染的五大特征,即:入河污水量大,点面源并重;有机污染严重,有机毒物突出;大城市排放集中;水污染趋势加重、冰封期问题突出;污染事故风险高。在此基础上,结合当前流域水环境管理的现状,识别了松花江流域水污染调控的主要问题,即缺乏系统协调性。提出松花江流域构建基于\"自然-人工\"二元水循环过程的水质水量联合调控体系的思路,在自然水循环和社会水循环两大层面七个方面基础上建立完整的水量控制及水质保障系统,并提出进行综合管理的体制和机制保障措施以及注重水污染的风险管理与应急机制建设的对策建议。  相似文献   

20.
深圳市水土保持管理信息系统是在智慧城市和智慧水务总体框架下,以深圳市水土保持业务特点为依据,做到水务数据统一存储与管理。系统由五大子系统组成,其中包含方案管理、监督检查、历史趋势可视化、实时预警等重点模块。通过搭建业务监管平台,实现了全流程监督管理。同时加入智能模型辅助管理人员决策和评价体系优化,让管理人员和业务人员的工作效率大幅提升。做到数据管理、业务支持、模型决策、数据可视化和实时预警等多项功能一体化。解决了深圳市水土保持信息化建设中信息处理能力不足,应用智慧化程度不高,业务来源和数据格式标准不统一,信息难以共享和调用,信息化系统无法支撑业务需求等问题。  相似文献   

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