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简介：河被知道带沉积负担。在包括Kosi，Brahmaputra，印度和黄的Bagmati河和中国的YarlungTsangpo河的亚洲的许多河为他们过多的沉积负担的马车是众所周知的。在印度，许多水抽象单位沿着河岸被定位。他们的成功取决于沉积负担怎么作为向抽的井的沉重的水流动定位了的沉积被套住很少百米离开河岸。在这个工作，基于在一条运河的推迟的负担变化上的一年的一个数据的分析，在Haridwar定位了，印度，陷井效率变化在来源水的经过期间被学习到抽象很好。就表面下的盆而言，在来源水和抽象以内定位了很好，作为假想安定盆，陷井效率的变化与流入的集中被联系。陷井效率取决于流入的集中，这被观察。为有流入的集中的陷井效率的变化的适当功能的形式也被识别。

简介：UsingfieldobservationsatfourgaugingstationsalongtheInnerMongoliaReachoftheYellowRiverinChina,thispaperexploreseffectsoftheiceonthehydraulicsofthisriverreachforfourdifferentconditions,namely:underopenchannelflow,duringice-runningperiod,theice-coveredperiod,andtheriverbreak-upperiod.Theratingcurveswerefoundtobewellrecognizedunderopenchannelsituations,butweresometimespoorlydefinedandextremelyvariableundericeconditions.Theresultsalsoshowthatthewaterlevelisinsensitivetoflowingicepriortofreeze-up.However,significant,buthardlysurprising,variationswereobservedduringice-coveredconditions.Theratingcurvesforboththeicecoveredconditionandrivericebreakupperiodaredevelopedandsomerelatedhydraulicissuesareexamined.Additionally,theimpactsoftheiceaccumulationandassociatedriverbeddeformationduringiceperiodontheratingcurvesarediscussed.

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简介：Reliablefielddataforallhydrologicparametersareoftenunavailableforwatershedsevenforthoseintensivelymonitored.Intheabsenceofreliablesuchdata,verifiedmathematicalrelationsforanareacanbeusedforotherareaswithsamehydrologicandclimaticregimes.Theobjectivesofthisresearchwere:1)toassessthetotalrunoffandsedimentloss,and2)todeveloprainfall,runoffandsoillossrelationsforfourprominentlanduses(includingdegraded,pasture,forestandagriculturelands)intheHilkotwatershed(Pakistan).Fourexperimentalnaturalrunoffplotswereestablishedonthelanduses(degraded,pasture,forestandagricultureland).ThefieldstudyanddatacollectionwereconductedintheHilkotwatershedfrom1999to2005.Regressionanalysiswasconductedtoestablishrelationsamongrainfall,runoffandsoillossforalllandusesusing.Regressionanalysisindicatedgoodcorrelationwithfielddata.

简介：地震沉积科学用地震数据是沉积岩石和外形的学习。然而，经常，沉积身体特征不能被描述份量上由于地震分辨率的限制。高决定倒置抵消这限制并且被用于地震沉积科学在复杂地质的条件下面识别微妙的陷井，从而拓宽地震沉积科学的适用的范围。在这篇论文，基于地震沉积科学，地震控制阶段的非线性的随机的倒置被用来在Shengli油矿在Chezhen消沉预言Es3的沙的集团企业水库。厚度和在几个阶段的沙的集团企业身体的沉积微外形地图被钻介绍，几个微妙的陷井被预言并且验证。

简介：烃探索兴趣为开发新潜水艇暗岩成像技术更新了需要。今天遇到的最重要的问题之一是在暗岩下面的地震成像。在最近的年里，这个问题看起来被长使用部分克服了抵消地震数据。然而近的偏移量数据充分还有待于由于表面以及暗岩的内部异质引起的复杂波形被利用。近正常的发生数据，影响亚暗岩成像，是高度有用的在暗岩层以内理解内部结构。为如此的目标的变换波浪的使用在相当同类的暗岩层作为一种选择被建议了。与合成建模这里行使的一些，我们在处理更多的现实主义、异构的暗岩流动加亮实际困难。完整的波形震动图被计算在地震数据上理解intra-trappean沉积的效果。从印度的Deccan陷井的案例研究在这篇论文被介绍。首先，我们在全面地震图象上讨论设置的沉积的效果。后来，来自这个领域的声音的木头数据被用来用反射率方法并且与领域数据相比计算完整的波浪地反应。使用模式的可行性变换了波浪(在顶和底部暗岩接口的到S并且反过来的P)因为在Kutch区域的亚暗岩成像通过一系列速度深度侧面被讨论。由与领域数据作比较，我们证明在暗岩罐头以内的多重薄layering的效果强烈败坏我们寻求解释并且利用的图象。

简介：FieldexperimentswereconductedontotalloadtransportintheChelichayRiverBasin,amountainouscatchment(1,400km~2)locatedinnortheasternofIran,toevaluatetotalloadformulasincludingfourgravelbedriversandasandbedriver(QaresooRiver).GravelbedriversinChelichayRiverBasincanbegroupedintotwotypes;steepsloperiverswithhighshearvalues(ChehelchayRiverandKhormalooRiver)andmildsloperiverswithlowshearvalues(NarmabRiverandSoosaraRiver).Twodepthintegratingsuspendedloadsamplers(DH-48andD-49),andtwobedloadsamplers(Helley-SmithandBLSH)wereusedtomeasuretotalload.Theperformanceistestedof8totalloadtransportformulaeincluding4macroscopicand4microscopicmethods.Asystematicandthoroughanalysisof59setsofdatacollectedfromsandbedriverindicatethatYangandEngelundandHansenreachtothebetterresults,andfromfourgravelbedriversconfirmedthatthemethodsofKarimandKennedyandEngelundandHansenyieldsthebestresultsforsteepsloperivers,andthemethodsofEinsteinandBijkerarerankedhighestingradualsloperivers.

简介：这研究的目的是估计在印度的东南的海岸在Tirumalairajan河河口在10表面沉积选择重金属(Fe，Mn，Cu，Zn，Pb，Cr，公司和Ni)划分的化学药品。一种五步的顺序的抽取技术被用来估计重金属的环境地位。大多数金属被认为由于在重金属的剩余部分的高可获得性不动。Tirumalairajan河河口的沉积没被重金属弄脏，并且他们没提出任何高生态的风险。重金属的季节的变化比在季风季节在夏天是稍微更高的。因素分析也被执行与沙，淤泥，泥土，有机物，pH，咸度和另外的金属在不同部分理解金属的协会。在Q模式和R模式簇分析之间的关系为在两个季节识别污染层次是有用的。重金属的丰富与地球表面形成学、人为的来源一起是相关的，这被证明。在沉积的全部的金属集中的信息不为在环境估计金属行为是足够的，但是顺序的抽取技术在估计污染沉积的环境影响是更有效的。

简介：河健康能被定义为河流的精力来源，水质量，流动政体，产地和生物区系匹配自然条件到的度。在一条健康的河里，物理过程和形式遗体活跃地连接了并且能互相调整、生物社区有差异的自然层次并且对环境应力有弹性。物理差异和生物多样性影响河健康。物理差异被水文学，hydraulics，和底层管理，在河隧道和邻近的泛滥平原的几何学思考了它为水、河边的有机体创造产地。生物多样性被象竞争和predation那样的生物过程管理，但是生物多样性也反映产地，以及连接的差异，丰富和稳定性。在一个河走廊以内的连接包括纵、侧面、垂直的尺寸。当任何这些交往的部件被人的活动损害，河健康衰退。水坝的累积效果和河的另外的人的改变主要是直接减少物理差异和连接，它间接地减少生物多样性。在水坝影响的河里的物理差异和生物多样性的恢复和维护要求在流动和沉积的驱动程序变量之间的确定的关系供应，和产地，连接，和生物社区的反应变量。这些关系能拿阀值的形式(例如，streambed沉积的乘火车)或反应曲线(例如，泛滥平原淹没的鱼生物资源对程度和持续时间)。我在西方的美国从怀俄明，科罗拉多，和亚利桑那使用例子说明怎么确定在在河里的司机和反应变量之间的关系由水坝影响了。

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简介：Retrogressiveerosion,awidespreadphenomenonofsedimenttransportinreservoirs,oftenimpactsonboththereservoircapacityandthesedimentationinthedownstreamriverchannel.BasedonfielddatafromtheSanmenxiaReservoirandtheLowerYellowRiveroverthepastdecades,threecoursesofretrogressiveerosionwithdistinctivefeatureswereanalyzed.Theresultsindicatethatretrogressiveerosion,especiallycausedbyrapidreductioninthewaterleveltillthereservoirisempty,oftenresultsintheserioussiltationofthelowerYellowRiverandthreatensthesafetyofthefloodcontrolintheLowerYellowRiver.Unreasonableoperationofthereservoirandincominghyperconcentratedfloodsaccompaniedbyretrogressiveerosionalsoaggravatethesiltationofthemainchanneloftheriver.However,areasonableoperationmodeofthereservoirsonamed”storingtheclear(lowsedimentconcentration)waterinthenon-floodseason,andsluicingthemuddy(highsedimentconcentration)waterinthefloodseason”wasfound,whichmightmitigatethedepositioninboththereservoirandtheLowerYellowRiver.Thisoperationmodeprovidesimportantexperienceforthedesignandoperationoflargereservoirsinotherlargeriverscarryinghugeamountsofsediment.

简介：MostofthestudiesonArtificialNeuralNetwork(ANN)modelsremainrestrictedtosmallerriversandcatchments.Inthispaper,anattempthasbeenmadetocorrelatevariabilityofsedimentloadswithrainfallandrunoffthroughtheapplicationoftheBackPropagationNeuralNetwork(BPNN)algorithmforalargetropicalriver.ThealgorithmandsimulationaredonethroughMATLABenvironment.Themethodologycomprisedofacollectionofdataonrainfall,waterdischarge,andsedimentdischargefortheNarmadaRiveratvariouslocations(alongwithtimevariables)andapplicationtodevelopathreelayerBPNNmodelforthepredictionofsedimentdischarges.Fortrainingandvalidationpurposesasetof549datapointsforthemonsoon(16June-15November)periodofthreeconsecutiveyears(1996–1998)wasused.Fortestingpurposes,theBPNNmodelwasfurthertrainedusingasetof732datapointsofmonsoonseasonoffouryears(2006–07to2009–10)atninestations.Themodelwastestedbypredictingdailysedimentloadforthemonsoonseasonoftheyear2010–11.ToevaluatetheperformanceoftheBPNNmodel,errorswerecalculatedbycomparingtheactualandpredictedloads.Thevalidationandtestingresultsobtainedatalltheselocationsaretabulatedanddiscussed.Resultsobtainedfromthemodelapplicationarerobustandencouragingnotonlyforthesub-basinsbutalsofortheentirebasin.Theseresultssuggestthattheproposedmodeliscapableofpredictingthedailysedimentloadevenatdownstreamlocations,whichshownonlinearityinthetransportationprocess.Overall,theproposedmodelwithfurthertrainingmightbeusefulinthepredictionofsedimentdischargesforlargeriverbasins.

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简介：ObservationoftheoperationoftheSanmenxiaReservoirontheYellowRiverhasledtotheconclusionthattopreserveacertaineffectivestoragevolumeforreservoirsbuiltonheavilysilt-ladenriversisfeasibleifthereservoirisoperatedaccordingtotheprincipleknownas"storingtheclearwateranddischargingthemuddyflow".Therelativestabilityofthebedelevationattheendofthebackwaterandthereservoir'serosionanddepositionequilibriumdependonthecompatibilityofthepoollevelmaintainedinnon-floodseasonswiththeconditionsofflowandsedimentloadduringfloodseasons.OperatingthereservoirtoregulatethefloodandsedimentloadduringfloodseasonscanreducetherateofaggradationintheLowerYellowRiver.Thebasicconditionforapplyingtheoperationmodeof"storingtheclearwateranddischargingthemuddyflow"isthatasufficientamountofwatershouldbeusedfordischargingsedimentduringfloodseasons.Undertheconditionofextremelylowflowyears,reservoirsedimentationcannotbeavoidedevenifthisoperationmodeisadopted.

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简介：Thepaperpresentsthe3DfiniteelementsimulationoftidalflowandSedimenttransportintheestuarineregionoftheHaiheriver.Theproposedmodeladoptssigma-transformationofthehydrodynamicandsedimenttransportequations.Thehydrodynamicandsedimenttransportmodelsareverifiedincaseofasimpletestproblemforwhichanalyticalsolutionsareavailable.FinallythemodelsareappliedtomuddyHaiheriverestuaryofNorthChinaanditisclaimedthathydrodynamicandsedimenttransportmodelsgiveareliablecomparisonwiththeobservedfielddata.However,therearecertaindiscrepancies,andsomereasonablequestionsregardingthepresentstate-of-art,inthemodelingofthree-dimensionalmultilevelhydrodynamicsandsedimenttransport,whichareprovidedbelowforanswer.