简介：Inordertoreducetheenvironmentalandecologicalproblemsinducedbywaterresourcesdevelopmentandutilization,thispaperproposesaconceptofenvironmentalandecologicalwaterrequirement.Itisdefinedastheminimumwateramounttobeconsumedbythenaturalwaterbodiestoconserveitsenvironmentalandecologicalfunctions.Basedonthedefinition,themethodsoncalculatingtheamountofenvironmentalandecologicalwaterrequirementaredetermined.InthecasestudyonHaihe-Luanheriversystem,thewaterrequirementisdividedintothreeparts,i.e.,thebasicin-streamflow,waterrequirementforsedimenttransferandwaterconsumptionbyevaporationofthelakesoreverglades.Theresultsofthecalculationshowthattheenvironmentalandecologicalwaterrequirementintheriversystemisabout124×108m3,including57×108m3forbasicin-streamflow,63×108m3forsedimenttransferand4×l08m3fornetevaporationlossoflakes.Thetotalamountofenvironmentalandecologicalwaterrequirementaccountsfor54%oftheamountofrunoff(228×108m3).However,itshouldberealizedthattheamountofenvironmentalandecologicalwaterrequirementmustbemorethanthatwehavecalculated.Accordingtothisresult,weconsiderthattherationalutilizationrateoftherunoffintheriversystemsmustnotbemorethan40%.Sincethecurrentutilizationrateoftheriversystem,whichisover80%,hasbeenfarbeyondthelimitation,theproblemsofenvironmentandecologyarequiteserious.Itisimperativetocontrolandadjustwaterdevelopmentandutilizationtoeliminatetheexistingproblemsandtoavoidthepotentialecologicalorenvironmentalcrisis.

简介：中国城市面对高、很快增加的暴露到灾难。减少灾难危险是为灾难管理和风险减小的一项直接、有效的反措施，它要求对社会和经济的危险的首先客观的评价。对经济危险的评价是在风险评估，为有效灾难预防计划的一个前提和为紧急情况管理的一个重要的底的重要的步。这份报纸为估计经济危险开发一个模型，它各种各样的工业部门和经济密度的企业，危险和重要性的尺寸考虑。基于模型，这份报纸开发一个城市的经济危险评估系统并且在北京把它用于Haidian区域，结果帮助鉴别在它的647，块在哪儿高度并且很高度以经济脆弱，并且它为灾难前预防计划提供有用、实际的信息，灾难有准备和紧急情况管理。在这研究开发的经济危险评价模型和系统使让政府快速评估一般经济危险并且识别特定的脆弱的区域可能，做对灾难管理信息系统和决定支持系统的贡献。

简介：EDSSisacomprehensivesoftwaresystemforwaterqualitymanagementintidalrivernetworksingeneralandforthePearlRiverDeltainparticular.Itspurposeistoprovideapracticaltoolthatcouldassistgovernmentagenciesindecisionmakingfortheefficientmanagementofwaterresourcesintermsofbothquantityandquality.Bycombiningthecapabilitiesofgeographicalinformationsystem(GIS),databasemanagementsystem(DBMS),modelbasemanagementsystem(MBMS)andexpertsystem,theaimistoimprovethequalityofdecisionmakinginwhatisbecominganincreasinglycomplexarea.ThispaperfirstoutlinesthebasicconceptsandphilosophyadoptedindevelopingEDSS,thesystemarchitecture,designfeatures,implementationtechniquesandfacilitiesprovided.Thereafter,thecorepartofthesystemthehydrodynamicandwaterqualitymodelsaredescribedbriefly.ThefinalcontributioninthispaperdescribestheapplicationofEDSStothePearlRiverDelta,whichhasthemostcomplicatedtidalrivernetworkpatternsaswellasthefastesteconomicdevelopmentintheworld.Examplesaregivenofthereal-worldproblemsthatcanbeaddressedusingthesystem,includingcross-boundarywaterpollutionanalysis,regionaldrinkingwatertake-upsiteselection,screeningofimportantpolluters,environmentalimpactassessment,andwaterqualityzoningandplanning.ItisillustratedthatEDSScanprovideefficientandscientificanalyticaltoolsforplanninganddecision-makingpurposesintheinformationera.

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