学科分类
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11 个结果
  • 简介:TheWorldAssociationofSedimentationandErosionResearch(WASER)establishedtheAwardfordistinguishedcontributionstosedimentresearchin2004.ThisawardistoprovideinternationalrecognitionfordistinguishedcontributionstothesedimentstudiesthroughoriginalandilluminatingresearchpaperspublishedintheInternationalJournalofSedimentResearch.Sevenpaperspublishedin2004-2009havebeenawardedthedistinguishedcontributionsawardin2007and2010.Aselectioncommittee,consistsof7scientistsfrom6counties,wasestablishin2012,whichscreened125paperpublishedinInternationalJournalofSedimentResearchduring2010-2012.Copiesof15papersintheshortlistweresenttomembersofthecommitteeandeachmemberwasrequestedtorecommend3papersfortheaward.ThevotingforthedistinguishedcontributionsawardstartedfromNovember1,2012viaemail.Allmembersoftheselectioncommitteehavereadthepapersandvotedfortheawardbasedonscientificmeritsofthesepapers.UptoJanuary10,2013,allthesevenmembershavesentbacktheirvotes,andtheresultsarethereforevalid.Thefollowing

  • 标签: 泥沙 国际期刊 研究论文 沉积物 启发性
  • 简介:Thepressureandimpactonlargerivershaveincreasedgreatlyinrecentyears,asaconsequenceoftheirexploitationtomeetvarioushumanneeds.Largeriversareparticularlyexposedtoproblemsofmultipleuses,oftenwithconflictingaims.Attheglobalscaleriversystemsareincreasinglyalteredbydams,leadingtointerruptionofcontinuityandadisruptedsedimentregime,whichresultsinfar-reachingproblems.Thesechallengespointalsototheneedformoreintegratedmanagementapproachesandconsiderationofcatchment-riverinteractionsemphasizinglandusemanagementandeffectsoftheseuses.Attheglobalscale,thereiscurrentlynooverviewassessmentofthecurrentstatusoftheworld’slargerivers,theconflictingdemandsonsuchrivers,andlikelyfutureanthropogenicimpacts,aswellasthepotentialforrestoration,improvementsinintegratedmanagementandtheassociatedproblemscausedbytheirmultipleuses.ThespecialissueintheInternationalJournalofSedimentResearchon"Sedimentloadsandprocessesinlargerivers"aimstoprovideaglobalforumforawide-rangingdiscussionofkeyissuesrelatedtoresearchonlargeriversandtotheireffectiveandsustainablemanagement,involvingbothscientistsanddecisionmakers.Thesequenceofpapersinthespecialissuehighlightsthecurrentsituationindifferentriversystemswithregardtomorphodynamicreactionsof

  • 标签: 大河 泥沙量 土地使用管理 河流系统 全球范围 相互作用
  • 简介:Toevaluatetheeffectofvegetativefilterstripsonsedimenttrapping,thespatialdistributionofdepositedsediment,andthesizedistributionofdepositedparticlesfromhyperconcentratedflows,asimulatedgrassfilterstripexperimentwasconductedwithplasticgrassusinganadjustableslopesteelflume.Thesimulatedvegetationcoverwas36%,andtheinflowsedimentconcentrationsappliedwere147,238,320,and429kgm~(-3).Thesedimentconcentrationintheoutflow,andthesedimentparticlesizeweredetermined.Theresultsshowedthatthegrassfilterstripstrappedmostofthesedimentfrominflowatlowsedimentconcentration.Thedepositionefficiencydecreasedwithincreasingsedimentconcentration,being55.2%and15.7%inthe147and429kgm~(-3)sedimenttreatments,respectively.Mostofthedepositedsedimentsweredistributedintheupperflume.Inaddition,thegrassfilterstripsmainlytrappedthecoarsesediment(particlesize>10μm).

  • 标签: 植被过滤带 高含沙水流 拦沙 泥沙沉积 泥沙颗粒 沉积物分布
  • 简介:TheblacksoilregionofnortheastChina,whichcoverstheProvincesofHeilongjiang,JilinandtheInnerMongoliaautonomousregionwithblacksoil,chernozemandmeadowsoil,hasexperiencedsoilerosionsinceintenseagriculturalreclamationbeganapproximately100yearsago.However,thesedimentdeliveryratio,definedasthefractionofgrosserosionthatistransportedfromagivenareainagiventimeinterval,isstillunclear.Inthisstudy,wecalculatedthedeliveryratioandanalysedchangesinerosiveprocesseswithinHebeicatchmentfrom1977to2007basedonananalysisofsedimentsoftheLiuduireservoir.Theoriginalvegetationlayerclearlyidentifiedthebottomofthereservoirwhenitwasconstructedin1977;thus,thereservoirsedimentscouldbepreciselydated.Thedeliveryratio,calculatedbycomparingthesedimentdepositioninthereservoirwiththetotalsoilerosionintheupstreamcatchment,wasfoundtobeexponentiallycorrelated(r~2=0.95,P<0.01)withdecreasinggrainsize,exceptforthefraction<0.002mm.Thedeliveryratiofortheclays(<0.002mm)waslow,averaging0.10duringthestudyperiod,whichindicatedpartialremovalofclaysfromthereservoir.Thechangesinthereservoirdepositionratereflectedthetemporalchangesintheerosionprocesses.Theexceptionallyhighrainfallin1998wasconfirmedbythedistributionsof~(137)Cs,~(210)Pb,andthegrain-sizeofthesediments.Beginningfromthepositionoftheoriginalgrasslayer,wedefinedthreeperiodsfrom1977to2007basedondepositionrates:2.40cmyear~(-1)from1977to1997,5.60cmyear~(-1)in1998duetounusuallyhighrainfall,and1.55cmyear~(-1)from1999to2007.Theoverallaveragedepositionratefortheentireperiodwas2.26cmyear~(-1).Precipitationwasfoundtobethemainfactoraffectingthesoilerosionofthestudyarea.

  • 标签: 东北黑土区 泥沙输移比 小流域 中国 平均沉积速率 沉积物分析
  • 简介:软沉积的变丑结构的间隔在在西方的Qaidamu盆的侏罗记湖的存款是暴露得好的。通过地观察,许多软沉积的变丑结构能被识别,例如旋绕的床上用品,液化的沙静脉,负担和火焰结构,商业萧条结构和重叠滑动的结构。基于他们的开始,软沉积的变丑结构能作为三种类型被分类:地震导致的结构,垂直装载结构,并且水平砍结构。基于他们的几何学和开始分析,他们是地震导致结构。根据旋绕的床上用品结构和液化的沙静脉的特征,在中间的侏罗记期间有比在学习区域的大小6大的地震,这能被推断。而且,商业萧条结构的学习和重叠滑动的结构显示在中间的侏罗记期间有一个东南的斜坡。自从到Altyn山和Altyn差错的来自学习区域的距离,是仅仅10km,Altyn山然后存在并且Altyn罢工滑倒差错在中间的侏罗记期间是活跃的,这能也被推断。

  • 标签: 柴达木盆地西部 中侏罗世 变形构造 沉积物 地震 阿尔金断裂带
  • 简介:Thedistributionofthesuspendedsedimentconcentration(SSC)intheBohaiSea,YellowSeaandEastChinaSea(BYECS)isstudiedbasedontheobservedturbiditydataandmodelsimulationresults.Theobservedturbidityresultsshowthat(i)thehighestSSCisfoundinthecoastalareaswhileintheoutershelfseaareasturbidwaterismuchmoredifficulttoobserve,(ii)thesurfacelayerSSCismuchlowerthanthebottomlayerSSCand(iii)thewinterSSCishigherthanthesummerSSC.TheRegionalOceanModelingSystem(ROMS)isusedtosimulatetheSSCdistributionintheBYECS.AcomparisonbetweenthemodeledSSCandtheobservedSSCintheBYECSshowsthatthemodeledSSCcanreproducetheprincipalfeaturesoftheSSCdistributionintheBYECS.Thedynamicmechanismsofthesedimenterosionandtransportprocessesarestudiedbasedonthemodeledresults.ThehorizontaldistributionoftheSSCintheBYECSismainlydeterminedbythecurrent-waveinducedbottomstressandthefine-grainsedimentdistribution.Thecurrent-inducedbottomstressismuchhigherthanthewave-inducedbottomstress,whichmeansthetidalcurrentsplayamoresignificantroleinthesedimentresuspensionthanthewindwaves.TheverticalmixingstrengthisstudiedbasedonthemixedlayerdepthandtheturbulentkineticenergydistributionintheBYECS.Thestrongwintertimeverticalmixing,whichismainlycausedbythestrongwindstressandsurfacecooling,leadstohighsurfacelayerSSCinwinter.HighsurfacelayerSSCinsummerisrestrictedinthecoastalareas.

  • 标签: 泥沙浓度分布 沉积物再悬浮 东中国海 渤海 黄海 模型模拟
  • 简介:Thepaperdescribesapermeametertestmethodfordeterminationofthehydraulicconductivity(AT)alongmulti-directionsinfluvialsedimentswithcrossbeddings.Unlikeexistingin-situpermeametermethodsthatdeterminehydraulicconductivityforsubmergedstreambeds,ourmethodwasintendedtomeasurehydraulicconductivityofexposedstreambedsorfluvialsediments.ThemethodwasappliedtotheWeiRiver,ShaanxiProvince,CentralChinaforcharacterizationoftheanisotropyofKinawell-sortedfluvialsediment.Theresultsillustratedthateveninwell-sortedsediments,cross-beddingandsedimentfabrication(ortexture)canleadtovariedKvaluesalongdifferentmeasurementdirections.TheKvaluewasthelargestalongthedipdirection(orthemajordirection)thatisparalleltotheorientationofcrossbeddingandthesmallestinthedirectionperpendiculartothebedding(ortheminordirection).TheKvalueinagivendirectionbetweenthemajorandminordirectionoftenfellintherangeboundedbytheKvaluesinthemajorandminordirections.TheanisotropyratioofK(theratioofKvaluebetweenthemajorandminordirections)intwotrenchesforthiswell-sortedfluvialsedimentwasupto1.14to1.23,respectively.Ourresultsalsodemonstratedthatevenforwell-sortedsediments,theKvaluesbetweentwosamplingpointsonlyabout10cmapartcandiffer.ItisclearthattheKdistributionstronglycorrelatestothebeddingorientation.

  • 标签: 水力传导系数 河流沉积物 各向异性 床上用品 排序 取向
  • 简介:全部的水银(THg)和甲基水银(MeHg)的集中为沿着福建省和东方广东省的沿海的线收集的32表面沉积被决定。THg和MeHg和他们的环境影响因素的空间分布被调查。在沉积的THg和MeHg的平均集中分别地是31.5ng/g和0.096ng/g。沉积THg和MeHg集中在Minjiang河口和Quanzhou和Putian的沿海的区域显示出相对高的价值。当到海岸线的距离增加了,集中总的来说减少了。在环境影响因素和THg之中的关联,MeHg被分析。沉积THg集中高度被相关到有机物,铜,全部的氮(TN)和全部的磷(TP)的集中,并且显著地相关到底部海水的pH价值和沉积硫化物的集中。沉积MeHg集中高度被相关到有机物和铜的集中,并且重要相关到硫化物,TN,TP和底部海水的pH价值的集中。

  • 标签: 环境影响因素 东部沿海 沉积物 广东省 福建省 汞形态
  • 简介:Climatechangecharacterizedbyincreasingtemperatureisabletoaffectprecipitationregimeandthussurfacehydrology.However,themannerinwhichriversedimentloadsrespondtoclimatechangeisnotwellunderstood,andrelatedassessmentregardingtheeffectofclimatechangeonsedimentloadsislacking.Wepresentaquantitativeestimateofchangesinsedimentloads(from1.5Gtyr~(-1)pre-1990to0.6Gtyr~(-1)from1991-2007)inresponsetoclimatechangeineightlargeChineserivers.Overthepastdecades,precipitationchangecoupledwithrisingtemperatureshasplayedasignificantroleininfluencingthesedimentdeliverydynamics,althoughhumanactivities,suchasreservoirconstruction,waterdiversion,sandminingandlandcoverchange,arestillthepredominantforces.Lowerprecipitationcoupledwithrisingtemperatureshassignificantlyreducedsedimentloadsdeliveredintotheseainsemi-aridclimates(4-61%).Incontrast,increasinglywarmerandwetterclimatesinsubtropicalzoneshasyieldedmoresediment(0.4-11%),althoughtheincreasewasoffsetbyhumanimpact.Ourresultsindicatethat,comparedwithmechanicalretentionbyreservoirs,waterreductioncausedbyclimatechangeorhumanwithdrawalshascontributedmoresedimentreductionfortheriverswithabundantsedimentsupplybutlimitedtransportcapacity(e.g.,theHuanghe).Furthermore,ourresultsindicatethatevery1%changeinprecipitationhasresultedina1.3%changeinwaterdischargeanda2%changeinsedimentloads.Inaddition,every1%changeinwaterdischargecausedbyprecipitationhasledtoa1.6%changeinsedimentloads,butthesamepercentageofwaterdischargechangecausedlargelybyhumanswouldonlyresultina0.9%changeinsedimentloads.Thesefigurescanbeusedasaguidelineforevaluatingtheresponsesofsedimentloadstoclimatechangeinsimilarclimatezonesbecausefutureglobalwarmingwillcausedramaticchangesinwaterandsedimentinriverbasinsworldwideatratespreviouslyunseen.

  • 标签: 入海泥沙量 气候变化 江河流域 中国 降水变化 土地覆盖变化
  • 简介:一个活动床的、未失真的物理模型(1:40)被用来通过河岸保护移动和丁提尺寸和配置的修正调查不同沉积供应策略到旧来因河,它引起河岸侵蚀。这条训练隧道以前巴塞尔(瑞士)下游地是上面的来因河的主要的床,但是自从宏大运河d'Alsace,一条航行运河,和一个流动控制水坝的构造,它在梳(法国)有人工地低的流动政体。训练工作和随后的隧道切口极大地也减少了沉积运输率并且创造一重重地armoured床。建模的飞行员地点在左河岸上有一个丁提领域。结果证明在这个地点的当前存在的丁提不在创造导致的高银行方面速度存侵蚀是有效的,甚至为比吝啬的年度流动率显著地高的流动率。河岸也比以前想证明了更抵抗,允许安全地要搬迁的河岸保护的长段。在二更高的、更大的岛丁提进一步分开被放比三存在依附的丁提的地方,测试进程的物理模型为丁提域生产了一种新配置。这条创新途径证明了有效,引起为在吝啬的年度流动率下面的流动率的河岸侵蚀,与被观察的一致侵蚀。如此的一种配置不为宏大运河d'Alsace提出危险,这也被发现了,它靠着旧来因河是位于的,通过在高流动事件期间的过多的河岸侵蚀。

  • 标签: 物理模型实验 河岸侵蚀 泥沙供给 莱茵河 多年平均流量 京杭大运河
  • 简介:LigninservesasoneofthemostimportantmolecularfossilsfortracingTerrestrialOrganicMatters(TOMs)inmarineenvironment.Extractionandderivatizationofligninoxidationproducts(LOPs)arecrucialforaccuratequantificationoflignininmarinesediment.Herewereportamodificationoftheconventionalalkalinecupricoxide(CuO)oxidationmethod,themodificationconsistinginasolidphaseextraction(SPE)andanovelon-columnderivatizationbeingemployedforbetterefficiencyandreproducibility.Inspikingblanks,recoverieswithSPEfortheLOPsarebetween77.84%and99.57%withrelativestandarddeviations(RSDs)rangingfrom0.57%to8.04%(n=3),whilethosewithtraditionalliquid-liquidextraction(LLE)arefrom44.52%to86.16%withRSDsbeingfrom0.53%to13.14%(n=3).Moreover,thereproducibilityisgreatlyimprovedwithSPE,withlesssolventconsumptionandshorterprocessingtime.Theaverageefficiencyofon-columnderivatizationforLOPsis100.8%±0.68%,whichissignificantlyhigherthanthoseofin-vialorin-syringederivatization,thusresultinginstilllessconsumptionofderivatizingreagents.LignininthesurfacesedimentssampledfromthesouthofYangtzeRiverestuary,China,wasdeterminedwiththeestablishedmethod.Recoveriesof72.66%to85.99%withstandarddeviationlessthan0.01mg/10gdryweightareobtainedexceptforp-hydroxyben-zaldehyde.ThelignincontentΣ8(producedfrom10gdrysediment)intheresearchareaisbetween0.231and0.587mg.S/VandC/Vratios(1.028±0.433and0.192±0.066,respectively)indicatethattheTOMsinthisregionareoriginatedfromamixtureofwoodyandnonwoodyangiospermplants;thehighvaluesof(Ad/Al)vsuggestthattheTOMshasbeenhighlydegraded.

  • 标签: 衍生化气相色谱 木质素含量 海洋沉积物 固相萃取柱 氧化铜 碱性