干旱与半干旱地区湿地水文及临界条件的模拟研究

  本文关键词：水利工程对向海湿地水文与生态的影响，由笔耕文化传播整理发布。

3??结论与建议

在干旱、半干旱地区,只有在降雨分布很集中的丰水年,才可能出现一些适合湿地植物生长的湿润期,而在其他绝大多数时间,地下水埋深很大,不具备湿地特征。外界入水量进入的时机不同,对湿润程度的提高也不同,影响因素有蒸发、前期及后期降雨量等。一般来说,在生长期初期和末期,由于蒸发量相对较小,同样的水量对湿润程度的提高相对较大。在力求满足美国陆军工程师团的最小水文准则时,该地区的临界供水量为12~15cm。对于干旱地区,不同时期的相同来水量,会引起不同的湿润变化,这对于湿地保护和恢复都是应该注意的问题。临界水量是该地区可以维持湿地水文的最小水量,因此在水资源规划时,应该给予足够的认识。

参??考??文??献:

[1]??王国平.水资源开发对科尔沁湿地环境的负面效应[J].国土与自然资源研究,2001,(2):45-47.

[2]??买买提??阿不都拉.新疆湿地现状与保护[J].新疆林业,2001,(4):4-5.

[3]??张振克,王苏民,吴瑞金,姜家虎.中国湖泊水资源问题与优化调控战略[J].自然资源学报,2001,16(1):16-

21.

[4]??鲁奇,刘洋.中国湿地消失的因素及保护对策[J].环境保护,2001,(10):21-23.

[5]??王国平,张玉霞.水利工程对向海湿地水文与生态的影响[J].资源科学,2002,24(3):26-30.

[6]??崔保山,刘兴土.三江平原饶力河流域湿地特征变化研究[J].自然资源学报,2001,16(2):107-114.

[7]??PoianiKA,JohnsonWC.Useofasimulationmodelinmanagingasemipermanentprairiewetland[M].Wetlandsympos??

ium,NorthernPrairieWildlifeResearchCenter,USGS,1998.

[8]??WetlandScienceInstitute(WSI).HydrologyToolsforWetlandDetermination(Chapter19)[M].NationalResourcesConser??

vationService,USDA,2001.

[9]??TweedyKL,EvansRO.HydrologicalCharacterizationoftwopriorconvertedwetlandrestorationsitesineasternNorth

Carolina[J].Trans.ASAE,2001,44:1135-1142.

[10]??SkaggsRW,ChescheirGM.Methodstodeterminelateraleffectsofadrainageditchonwetlandhydrology[M].2002ASAE

AnnualInternationalMeeting,St.Joseph,Mich.,ASAE.2002.

[11]??贾忠华,罗纨,王文焰,SkaggsRW.对湿地定义和湿地水文特征的探讨[J].水土保持学报,2001,15(6):117-

120.

[12]??WaterwayExperimentStation(WES).WetlandsDelineationManual,1987(RevisedversionwasadoptedbytheSection404,

CleanWaterAct,1997)[M].WetlandsResearchProgramTechnicalReportY??87??1(onlineedition):28-34.WaterwayExperimentStation,CorpsofEngineering,USArmy,1987.

[13]??SkaggsRW.Fieldevaluationofawatermanagementsimulationmodel[J].Trans.ASAE1982,25(3):666-674.

[14]??KandilHM,SkaggsRW,AbdelDayemS,AiadY.DRAINMOD??S:watermanagementmodelforirrigatedaridlands,crop

yieldandapplications[J].IrrigationandDrainageSystems,1995,(9):239-258.

[15]??BreveMA,SkaggsRW,ParsonsJE,GilliamJW.DRAINMODN,ANitrogenmodelforartificiallydrainedsoils[J].

Trans.ASAE,1997,40(4):1067-1075.

[16]??LuoW,SkaggsRW,ChescheirGM.DRAINMODModificationsforColdConditions[J].Trans.ASAE,2000,43(6):1569

-1582.

[17]??SkaggsRW,FauseyNR,NolteBN.WatermanagementevaluationfornorthcentralOhio[J].Trans.ASAE,1981,24(4):

922-928.

[18]??ChangAC,SkaggsRW,HermsmeierLF,JohnsonWR.Evaluationofawatermanagementmodelforirrigatedagriculture

[J].Trans.ASAE,1983,26(2):412-418.

[19]??GayleG,SkaggsRW,CarterCE.EvaluationofawatermanagementmodelforaLouisianasugarcanefield[J].J.Am.

Soc.Sugar??CaneTechnil.,1985,(4):18-28.

[20]??FoussJL,BengtsonRL,CarterCE.SimulatingsubsurfacedrainageinthelowerMississippivalleywithDRAINMOD[J].

Trans.ASAE,1987,30(6):1679-1688.

[21]??McMahonPC,MostaghimiS,WrightFS.Simulationofcornyieldbyawatermanagementmodelforacoastalplainssoil

[J].Trans.ASAE,1988,31(3):734-742.

[22]??SkaggsRW,AmatyaD,EvansRO,ParsonsJE.Characterizationandevaluationofproposedhydrologiccriteriaforwet??

lands[J].J.SoilandWaterCons.,1994,49(5):501-510.

Studyonhydrologicaldynamicsandformationcriteriaofwetlands

JIAZhong??hua,LUOWan,ZHOUXiao??xia,LIUXiao??ning

(Xi??anUniversityofTechnology,Xi??an??710048,China)

Abstract:ThedataofprecipitationandsoilpropertiesinXi??anareaareanalyzedbyusingthehydrologi??calmodelDRAINMODtoinvestigatetheinfluenceofincomingwateronvariationofgroundwatertable.ThemodelissuggestedbytheWetlandResearchInstitute,DepartmentofAgriculture,USA.Atthesametime,theidentificationcriterioncurrentlyadoptedinUSisappliedtoanalyzethenecessarycriticalincom??ingwaterforwetlandformation.Itisfoundthattheincomingwaterwiththesameflowdischargemayre??sultindifferentwetnessindifferentmonthsinayear.Consequently,thenecessarywaterflowforformingthecriticalhydrologicalconditionisnotaconstant.

Keywords:wetland;wetlandhydrology;DRAINMOD;modeling

(上接第26页)

FractureanalysisoninducedjointofRCCdams

SONGYu??pu,ZHANGLin??jin,YINFu??xin

(DalianUniversityofTechnology,Dalian??116024,China)

Abstract:Inordertodeducetheformulaforstressintensityfactoroftwo??directionintervaljointinRCCdams,thestressintensityfactorofthecracktipsinellipticalandrectangularinducedjointsareanalyzedbyusing3??DFEM.Thecomparisonshowsthatthecalculationresultsofthesetwokindsofjointareap??proximatelythesame.Buttheellipticalmodelismoreconvenientforpracticaluse.Consequently,theformulaofthestressintensityfactorforthecracktipsofellipticalinducedjointinfinitebodyisextendedtomeetthecalculationforfinitebody.Onthisbasis,theregressionanalysismethodisadoptedtoestab??lishtheformulaforcalculatingthestressintensityfactoroftwo??directionintervaljoint.Intheformulathesizeanddimensionsofinducingplateaswellastheinfluenceofweakeningdegreearetakenintoaccount.Keywords:RCCdam;inducedjoint;stressintensityfactor;3??DFEM

五星文库wxphp.com包含总结汇报、旅游景点、专业文献、资格考试、出国留学、文档下载、考试资料以及干旱与半干旱地区湿地水文及临界条件的模拟研究等内容。

本文共2页12

  本文关键词：水利工程对向海湿地水文与生态的影响，由笔耕文化传播整理发布。