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1IntroductionDuringthepasttwodecadesofeconomicreform,China'snationaleconomyhasgrownrapidlyandthestandardofliving,notablyfoodconsumption,hasimprovedsubstan-tially.Alongsidethisachievementtherehasbeenanincreaseinthetotalvolumeofwateruse.Between1980and1998totalwaterwithdrawalincreasedfrom443.7billionm3(UnitedNations,1997)to543.5billionm3(MinistryofWaterResources,2000).Anoteworthyfeatureisthattheincreasedwaterwithdrawalwasoverwhelminglyattributabletotheexpansionofmunicipalandindustrialuses.Thevolumeofwaterforirrigationincreasedrelativelylittle,from358billionm3in1980to369billionm3in1998.Duringthisperiod,irrigatedareasrosefrom44.96millionhato52.29millionha,indicatingadeclineinaveragewateruseperunitofirrigatedland.Theshareofirrigationintotalwaterwithdrawaldroppedfromaround80%to68%duringthesameperiod.Onthesupplyside,however,thesituationisrathersevere.Watershortageshaveoccurredinmanyareas,particularlyinthenorth.Itisreportedthatinsomenortherncities,watersupplycanmeetbarely70%ofthedemandduringthedryseason(MinistryofWaterResources,1998).Watershortagehascausedhardshipstohouseholdlive-lihoodsandlossesintheoveralleconomy,includinggrainoutput.Theincreasingwaterscarcityandthecompetitionfromothersectorshaveputirrigationundergreatpressureinmanynorthernregions.Grainproduction,asectorheavilydependentonirrigation,isfacingunprecedentedchallenge.TheincreasingwaterstresshasledtoaflourishingofstudiesofChina'swaterissues(BrownandHalweil,1998;Chenetal,1999;Conradetal,1998;Heilig,1999;Jiang,2000;Li,1999;LiuandHe,1996;Nickum,1995;1998;Zhang,2000,Zhu,2000).Surprisingly,exceptforafewextremelypessimisticprojections,(1)mostpeople,partic-ularlytheChinesethemselves,believethatChinahasenoughwatertomeetthedemandforindustrialgrowth,householduses,aswellasgrainproductionintheyearstocome.China'sregionalwaterscarcityandimplicationsforgrainsupplyandtradeHongYang,AlexanderZehnderSwissFederalInstituteforEnvironmentalScienceandTechnology,Uberlandstrasse133,CH-8600Dubendorf,Switzerland;e-mail:hong.yang@eawag.ch,zehnder@eawag.chReceived11April2000;inrevisedform15September2000EnvironmentandPlanningA2001,volume33,pages79^95Abstract.InthispaperwehighlightthewaterscarcityandresourcedepletionintheNorthChinaPlain,the`breadbasket'ofChina.Aprojectionofwaterdemandintheregionindicatesacontinuousaggravationinwaterdeficitinthecomingyears.Analysesofcountermeasuresonthesupplyanddemandsidesuggestthattheconventionalwisdomof`openingupnewsourcesandeconomisingontheuseofresources'maynotbeanoptimalwaytodealwithwaterscarcityintheregion.Importingwaterintheformofgrainshouldbetakenasanadditionalmeasure.This`virtualwaterimport'optionneedstobeincorporatedintothecurrentregionalandnationalagriculturaldevelopmentstrategyinwhichcropstructuraladjustmentisatthecore.(1)Forexample,BrownandHalweil(1998)warnedthatChinahasbeenwithdrawingmorewaterthanthesustainableamountavailable.Theyprojectedawaterdemandof1068billionm3for2030.Foodproductionwilleventuallyfallastheresultofthedepletionofwaterresources.Chinawouldhavetoincreaseimportstomeetitsgrowingfooddemand.Thiscouldpushupfoodpricesintheworldmarketandshakeinternationalfoodsecurity.DOI:10.1068/a3352Thecurrentwatershortagecrisisisratherlocalised,economic,andinstitutional.ManyfeelthatChina'swaterproblemcanbesolvedlocallyoratmostwithinitsnationalboundary.Thisviewisreflectedbythefactthatmoststudiesofmeasuresdealingwithwaterscarcityhavenotconsideredtheroleofinterregionalandinternationaltrade.Measuresprescribedhavemainlybeenlocallyoriented,aimingeithertoincreasewatersupply(includingtransferringwaterfromoutside)ortousetheavailablewatermoreefficiently.Asforthefewstudiesthathaveconsideredtrade(forexample,BrownandHalweil,1998;Conradetal,1998),theapproachisoftentosetagoalofgrainoutputforaregionorforthecountryandthentoassesswhetherornotthereisenoughwatertoproducethispresetoutput.Ifnot,importsareneeded.InthisstudyweattempttobringanewperspectiveintothesearchforsolutionsforChina'sregionalwaterscarcity.Asirrigationisbyfarthelargestwateruserandfoodsecurityisoneofthemostimportantconcernsofthecountry,wefocusontheimpactofregionalwaterscarcityonirrigationandmeasurestodealwithit.Thepaperbeginswithabriefoverviewofwater-resourceendowmentatthenationalandregionallevel.Wethenturntothewater-scarceNorthChinaPlainprovincesandexaminethechangesinirrigatedareasandsourcesofirrigationwaterduringthepasttwodecades.ThisisfollowedbyaprojectionofwaterdemandintheNorthChinaPlainprovincesinthecomingtwodecades.Theresultshowsaseveredepletionofwaterresources.Ifthecurrenttrendcontinuestherewillbeacontinuousaggravationinwaterdeficitintheregion.Theanalysisalsosuggeststhatconventionaldemand-and-supplymanage-mentmeasuresmaynotbeanoptimalwaytodealwiththewater-shortageproblemintheNorthChinaPlain.Anoutward-lookingmeasureöimportingwaterintheformofgrainöisproposedasanadditionalapproach.Itisemphasisedthatthismeasureshouldbeincorporatedintothecurrentregionalandnationalagriculturaldevelopmentstrategyinwhichagriculturalstructuraladjustmentisatthecore.TheanalysisisbasedmainlyonChineseofficialstatisticsinc