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1LiteraturesSource第1頁/共44頁Articlestructure1、Titleandauthor2、SummaryPhase4Phase3Phase2Phase11、Introduction2、Background1、Sampling2、Analyses

1、ResultsandDiscussion2、Conclusions3、references第2頁/共44頁12334435

Summary

ContentsIntroductionandBackgroundSamplingandAnalysesResultsandDiscussion

Conclusions第3頁/共44頁41.Summary1、提出問題:TheLowerTarimRiverinNWChinaisundersevereecosystemdegradationduetostoppedstreamflowanddiminishedgroundwaterrecharge.Sinceyear2000,eightwaterdiversionsfromtheupperstreamandfromtheneighboringKaidu–KongqueRiverhavebeenimplementedtoalleviatetheecosystemdisaster.中國西北部塔里木河下游面臨嚴重生態(tài)退化是由于河流斷流和地下水補給減少造成的。自2000年以來,通過從鄰近的開都和孔雀河等河流上游的八次引水調(diào)度已經(jīng)緩解塔里木河生態(tài)環(huán)境問題。第4頁/共44頁51.Summary2、研究方法:wesampledtheripariangroundwatersystemin2007and2008alongthe350km-longriverchannelthroughthe40monitoringwellssituatedalongninetransectsperpendiculartotheriverandthreesoilprofiles.Measurementsonthesampleshaveincludedenvironmentalisotopes(18O,2H,3H)andwaterchemistry.我們沿河岸地下水系統(tǒng)在2007年和2008年沿著350公里河道,通過40個坐落在河流附近的監(jiān)測井進行采樣。測量樣品項目包括環(huán)境同位素(18O,2H,3H)和水化學。第5頁/共44頁61.Summary3、研究結(jié)果:Remarkablechangeshavebeeninducedbythewaterdiversions

asfollows：(1)Theobservedresponseofripariangroundwatersystemincludesgeneraldecreaseintotaldissolvedsolid(TDS)andriseofwatertable.Greaterriseofwatertableoccursneartheriverbank.沿河岸地下水系統(tǒng)觀察結(jié)果包括:總?cè)芙夤腆w(TDS)減少和水位上升。更大的地下水位上升發(fā)生在河岸附近。(2)Tritiumdatashowthattheextentofmodernrecharge(since1960s),includingthatfromthedivertedwater,islimitedto600mfromtheriverbankattheuppersegmentsand200matthelowerones.氚數(shù)據(jù)顯示,現(xiàn)代水補給范圍(since1960s),包括從轉(zhuǎn)移水,僅限于上游河岸600米內(nèi)部分和下游200米內(nèi)。第6頁/共44頁71.Summary(3)Stableisotopesshowthatgroundwatersareenrichedinheavyisotopesandareplottedinparalleltothemeteoricwaterline,attributedtoevaporationduringrecharge.穩(wěn)定同位素表明,地區(qū)地下水重同位素豐富,并與大氣降水線平行,歸因于蒸發(fā)。(4)GroundwaterisgenerallyofNa–Mg–Cl–SO4typeandisformedbydissolutionofminerals.Thesalinityofgroundwaterismainlyaffectedbythatofthedivertedwaterandofthelocalantecedentgroundwater,saltsintheunsaturatedzone,evapotranspirationduringrecharge.地下水一般由Na-Mg-Cl-SO4類型和溶解的礦物質(zhì)組成。地下水鹽度主要是受轉(zhuǎn)移水和當?shù)厍捌诘叵滤?在非飽和區(qū)的鹽度,蒸散發(fā)影響。第7頁/共44頁81.Summary(5)Asthezoneofsmallergroundwaterdepth(lessthan5m)suitableforthemostexistingPopuluseuphraticaandTamarixramosissima,themainspeciestargetedbytherescueeffort.正如較小的一部分區(qū)域地下水深度(小于5米)適用于大多數(shù)現(xiàn)有胡楊和檉柳,它們是保護的主要目標。第8頁/共44頁92、IntroductionandBackgroundWaterdiversionGeneralsettingHydrogeologyClimateEcosystemdegradationIntroductionandBackground第9頁/共44頁102、IntroductionandBackgroundIntroduction:Underthedualimpactsofanthropogenicactivitiesandclimatechange,acommonscenarioinaridandsemiaridcatchments,particularlyinthelowerreachesofthem,issevereecologicaldegradation,suchasdeathofvegetation,intensifiedgroundwatersalinization,soilsalinizationanddesertification,etc.介紹：人為活動和氣候變化的雙重影響下,一個常見的場景在干旱和半干旱區(qū),特別是在下游,是嚴重的生態(tài)退化,如植被死亡,加劇地下水鹽漬化、土壤鹽漬化、沙漠化等。

第10頁/共44頁11Background:1、GeneralsettingTheTarimRiverBasinislocatedinthesouthofXinjiang,NWChina.Ithasanareaof1.04x106km2andisflankedbytheTianshanMountainstothenorthandbytheKunlunMountainstothesouth(Fig.1).2、HydrogeologyTheoccurrenceofgroundwaterissimilarbetweentheSouthernTianshanwatershedandNorthernKunlunwatershed.ThesinkofthetwogroundwaterssystemsiscenteredinthesouthoftheTarimRiver.Thediluvialaquiferfromthenorthernmountainsiscomposedofsanddepositssome100–300mthickforminganunconfinedaquiferinwhichthepresentdaywatertablerangesbetween20mand200mbelowsurface(Fig.2).

2、IntroductionandBackground第11頁/共44頁12Fig.1SketchmapoftheTarimRiverBasin1–Proterozoic;2–Paleozoic;3–Mesozoic;4–tertiary;5–granite;6–quaternary;7–river;8–surfacewaterintheUpperTarimRiverandtheAksuRiver;9–regionalgroundwaterflow.第12頁/共44頁13Fig.2HydrogeologicalcrosssectionintheMiddleTarimRiver,seeFig.1forthelocation第13頁/共44頁14Background:3、ClimateTheLowerTarimRiverisdominatedbytypicalcontinentaltemperatearidclimate.4、EcosystemdegradationUndertheimpactofanthropogenicactivities,runoffofthreesourcestreams(AksuRiver,HotanRiverandYarkantRiver)totheTarimRiverhasdecreasedgraduallyinthelast50yearsduetoextensiveoasisagriculturewithincreasingwaterutilization.WithgraduallydecreasedinflowtotheTarimRiver,proportionofwaterconsumptionintheupperandmiddlereachesincreasedgraduallyfrom1970sto1990s,whileflowtothelowerreachesreducedsignificantly(Table1).Thegroundwaterdepthhasincreasedto8–12m.

2、IntroductionandBackground第14頁/共44頁Station1950s1960s1970s1980s1990sAral49.451.744.444.842.0Qiala13.511.46.73.92.8Tikanlik8–92.90.50.40.1ArganPersistDiscontinueNilNilNilLopVillage5–40.2NilNilNil15Table1RunoffchangesateachstationontheTarimRiver(108m3).5、WaterdiversionToprotecttheGreenCorridor,theriparianvegetationrestorationisimperative.TakingadvantageofthewetperiodoftheKaiduRiver,theKu–TaChannel(YulitoQiala,Fig.3)wasconstructedfordivertingwaterfromKongqueRivertotheLowerTarimRiver.

第15頁/共44頁16Fig.3Samplinglocations

第16頁/共44頁17

Table2Statisticsofeightwaterdiversions第17頁/共44頁183.SamplingandAnalyses采樣點布置及前期準備穩(wěn)定同位素測定方法及標準18O,2H,3H穩(wěn)定同位素測量八次引水后塔里木河流域下游地下水的物理化學變化規(guī)律及特征水化學測定方法及標準采樣方法及具體實施步驟水化學離子色譜法測定地下水位、位置,水溫、pH值、TDS和電導(dǎo)率測定第18頁/共44頁19Sampling：Groundwatersampleswerecollectedfromboreholesatvaryingdistancesfromtheriverbedalongninegroundwatermonitoringtransects,namely:Akdun(A),Yahopumarhan(B),Yengsu(C),Abudali(D),Karday(E),Tugmailai(F),Aragan(G),Yikanbujima(H),andKargan(I)(Fig.3),respectively.Method：Thesoilsampleswereobtainedusingahollow-stemhandaugerwithinterchangeable1.5maluminumrodfromthreeprofiles(5.8–7.7mdepth,SP1andSP2insectionCandSP4insectionG,Figs.3and4).Bulksoilsamplesof400gwerecollectedatintervalsof0.25m.Sampleswerehomogenizedoverthesampledintervalandimmediatelysealedinpolyethylenebags.3.SamplingandAnalyses第19頁/共44頁20Method：Gravimetricmoisturecontentwasdeterminedbydryingaminimumof80gofsoilat110Cfor12h.Todeterminechloridecontent,doubledeionisedwater(40mL)wasaddedtotheoven-driedsoilsample(40g).Sampleswereagitatedonareciprocalshakertablefor8h.Thesupernatantwasfilteredthrough0.45lmfilters.Chloridewasthenanalyzedbyionchromatography.Thechlorideconcentrationofthesoilsolutionisthencalculatedbydividingthemeasuredconcentrationbygravimetricmoisturecontentandbymultiplyingthemassratioofsolutiontoovendrysoil.3.SamplingandAnalyses第20頁/共44頁21

Table3Sitemeasurementsandisotopiccompositionofsurfacewaters.Analyses：第21頁/共44頁22

Table4Chemicalcompositionofthesurfacewaterandgroundwatersections(mg/L).第22頁/共44頁23

4.ResultsanddiscussionPhase1Phase2Phase3TritiumandstableisotopeanalysisHydrochemicalcharacteristicsWatertableandTDSchange第23頁/共44頁24

Fig.4Theprecipitationtritiuminputfrom1952to2007andthedecayedvaluefor2007.Theresultsshowatritiumcontentdecreasefrom2586TU(1963)to20~30TU(2007).Usinganexponentialdecayequation,thedecayedtritiumcontentsfor2007inprecipitation,whichwouldrepresenttritiumconcentrationsingroundwaterthathadinfiltratedbetween1952and2007,rangesfrom50TUto225TUfrom1962to1966,andrangesfrom10to35TUfrom1957to2007(Fig.4).Therefore,groundwaterwithtritiumcontentlessthan10TUisregardedaspre-modernwater,oratleastmostpartispre-modernwaterwhenmixingwithmodernwaterisconsidered.Tritiumanalysis第24頁/共44頁25Fig.5.PostmapofTritiumcontent(TU)forgroundwatersfromtheLowerTarimRiverwithasolidlineshowingthescopeofmodernrecharge.Fig.5showsthetritiumcontentsintheripariangroundwaterfromtheLowerTarimRiver.Thesolidlineinthefigureistheboundarybetweengroundwaterthatisrechargedbymodernwater(19.1–46.3TU)andthatbypre-modernwater(lessthan4.1TU).Tritiumanalysis第25頁/共44頁26Fig.6Thestableisotopesinthewaterreservoirsinthelowerreachesareenrichedinheavyisotopesduetoevaporation:theQialaWaterReservoirhastheδ18Oof4.6‰andtheDaxihaiziWaterReservoirhastheδ18Oof3.6‰duetoextendedevaporation.TheresidualwaterscollectedfromtheriverbedattheLowerTarimRivershowδ18Ofrom2.0‰to3.5‰andδ2Hfrom17.1‰to5.8‰,asaconsequenceofintensiveevaporation.StableisotopeanalysisinsurfacewatersFig.6Stableisotopiccompositionforsurfacewatersandgroundwaters第26頁/共44頁27Themodernandpre-moderngroundwatersexhibitasimilarbehaviortofallinslightparalleltothemeteoricwaterline,butenrichedrelativetotherechargingriverwater.Thephenomenoniscommonlyobservedindryclimateandattributedtoevaporationduringriverrechargetotheripariangroundwatersysteminaratheruniformmanner.Fig.7StableisotopiccompositionforsurfacewatersandgroundwatersStableisotopeanalysisingroundwatersFig.6Stableisotopiccompositionforsurfacewatersandgroundwaters第27頁/共44頁28piper三線圖以三組生要的陽離子(Ca,Mg,Na和K)和陰離子(C1,S04,HCO3和CO3)的每升毫克當量的百分數(shù)來表示。每圖包括三個部分，在左下方和右下方分別為二張等腰三角形域，中間上方夾著一張菱形域(圖1)，每域的邊長均按100等分讀數(shù)。在左下方的等腰三角形域，三個主要陽離子反應(yīng)值的百分數(shù)按三線座標用一個單點表示。在右下方的等腰三角形域，陰離子亦用同樣方法表示。這樣，圖上所作的二單點表示了地下水中某些溶解物質(zhì)的相對濃度。然后通過這二個單點平行三角形外邊作射線，于菱形域內(nèi)相交一點。這一點通?？梢哉f明地下水總的化學性質(zhì)并用陰陽離子對表示地下水的相對成分。Hydrochemicalcharacteristics第28頁/共44頁29ThewatertypeconversionfromCa–Mg–HCO3–SO4withlowTDSinsourcestreamtoNa–Mg–Cl–SO4withhighTDSinthelowerreachesofthebasinandfluorideconcentrationevolutionshowtheoneofthemosttypicalwaterevolutionofaridwatersystem,goingalongwithevaporationanddissolution.Fig.7Pipertrigraphforsurfacewaters（a）andgroundwaters（b）Hydrochemicalcharacteristics（a）（b）第29頁/共44頁30TDSinthegroundwaterwithin600mtotheriverbedrangesfrom0.8g/L(E3)to3.7g/L.(C1)withanaverageof1.6g/L,exceptforsectionI,whichislocatedintheterminalofthewaterflowandsaltwithveryhighTDS.Beyondthedistance,TDSingroundwaterisalsohighexceptforsampleG5.Fig.8TDSdistribution(g/L)intheLowerTarimRiverHydrochemicalcharacteristics第30頁/共44頁31ThestrongcorrelationsbetweenNaandCl(r=1.00)andanapproximately1:1trend(Fig.9a)suggestNaandClmainlycomesfromhalite.CaandMghavestrongcorrelationswithSO4(0.97,1.00)andrelativelyweakwithHCO3(0.77,0.84).Theequivalentratiosfor(Ca+Mg)againstHCO3aremorethan1(Fig.9b),suggestingthat,besidesdissolutionofcarbonates,dissolutionofsulfate(CaXMg(1-X)SO4)contributestheadditional(Ca+Mg)whenconcentrationof(Ca+Mg)increaseswiththatofSO4.Suchapatternindicatesthatsaturationofarelevantsaltcontrolstheconcentrationoftherespectiveions.Fig.9Ionicratioforthegroundwaters.Groundwatersaliizationmechanism第31頁/共44頁32Fig.10showsthechlorideconcentrationindrysoil,appearingtobehighlyvariable.TheSP1haslesschlorideinthewholeprofile,rangingfrom24to862mg/kg,comparedtotheSP2andSP4,whichshowmaximumchlorideconcentrationof4416mg/kg(2.05–2.30mdepth)and11,925mg/kg(0.35–1.00mdepth),respectively.Fig.10Moistureandchloridecontentforthethreesoilprofiles第32頁/共44頁33Fig.11WatertablesandTDSchangesatcertaingroundwatermonitoringsectionintheLowerTarimRiverunderwaterdiversions第33頁/共44頁34Thevariationsofwatertableshavethefollowingcharacteristics:beforethewaterdiversion,thewatertablesweresimilarateachsectionandtheflowfieldwasstable;afterthewaterdiversion,thewatertablesrosetodifferentextent.Theclosertotheriverbed,thefasterthegroundwatertablerose.Theunstableinfiltrationtakesplaceatriverbed,asaresult,thehighgroundwaterhydraulicheadmovestowardsbothriver-sides.ChangesofTDSingroundwatersshowthefollowingcharacteristics:TDSingroundwaterfromsectionsBandChasincreasedafterthefirstdiversion;afterthesecondandthirdwaterdiversions,TDSingroundwatersfromallsectionshasdecreased.TheTDSforsamplesC7(w8,850mawayfromtheriver)tempestuouslyincreasedfrom4.57g/Lto22.37g/Lafterthefourthwaterdiversion,to15.32g/LinAugust,2007.WatertableandTDSchange第34頁/共44頁35Fig.12Thevariationofgroundwatertable(m)beforewaterdiversionandaftertheeighthwaterdiversion(a)andgroundwaterdepth(m)intheLowerTarimRiver(August,2007).Thevariationofgroundwatertablebetweenthatbeforewaterdiversion(05/2000)andaftertheeighththewaterdiversion(08/2007)andthegroundwaterdepth(08/2007)areplottedinFig.15usingtheInverseDistanceWeightingMethod.4.Resultsanddiscussion第35頁/共44頁36Thescopesofwatertablesrisearewiderthanmodernrechargelimit,duetowaterheadpressuretransfer.Sincethevegetationcoverageexhibitsacontinueddecliningtrendwithdroppingwatertableandmodernwaterrechargescopeinthearea,NiuandLi(2008)concludedtherewas7345hm2increasedvegetationareafrom2000to2006afterwaterdiversionbasedonsatelliteimagesofthemainareawherevegetationdistributedintheLowerTarimRiver.

However,thegroundwaterdepthsuitableforthegrowthofP.euphraticaislessthan5mintheLowerTarimRiver,IfthetargetoftheecologicalrestorationistomaintainthevegetationdominatedbyP.euphratica,theoptimalgroundwaterdepthwouldbelessthan5m.However,theterritorywiththesuitablegroundwaterdepthisnarrow,within200mfromtheriverbedandbecomesevennarrowertowardsdownstream4.Resultsanddiscussion第36頁/共44頁371、TheisotopiccompositionofshallowgroundwaterformsatrendlinethatisalmostinparalleltotheGMWLbutisenrichedinheavyisotopescomparedwiththerechargingriverwater.Thiscanbeattributedtoevaporationduringtheriverrechargetotheripariangroundwatersysteminaratheruniformmanner.淺層地下水的同位素組成,形成一個趨勢線,幾乎是平行于GMWL，與河水相比重同位素值更大。歸因于河水補給地下水系統(tǒng)過程間的蒸發(fā)作用。2、Tritiumdatashowthattheextentofmodernrecharge(since1960)islimitedto600–200mfromtheriverbankwithadescendingtrendtowardsdownstr