【正文】 km3Water Cycle in NCP Hydrologic Detention pMajor features of NCP’s water resourceskm3km3 Strategic measures:5. To enhance and to work out integration of agronomic and engineering measures (or engineering nonengineering) to form watersaving agriculture systems。3. To improve WaterUsing Efficiency ( WUE for grain yield) is a main target。To manage water resources is an extremely important issue. There is a pressing need to move away from the past practices of unplanned irrigationinfrastructure and move towards consideration of water governance for water renewability. (3) high capability (4) high applicability and (5) low cost pared with water diversions。understanding7. To resolve water shortage problem, biotech has a prosperity advantages:(1) high reliability for water saving。5. Water saving has great potential。Major 3. Agriculture can use allkind of water, including “green and blue waters”and recycling water and unconventional water as well。understanding1. Food security is subject to water supply。ditch(fineirrigationDitchtheplotsIrrigationwithsurfaceBorderirrigationSeepingpipe DripthroughpipeWaterlowconveyed(cleeksystemsLinedmeasureAgronomic measures subsystem Watersaving engineering and technical measurerWaters conveyance worksWatersaving irrigation techniquesAssociatiedirrigationMulchingirrigationControlledRegulatedsavingapplicationLimitedmoisturesavingstructureWatermatchedschemeWatermatchedtechnologyWatersavingwatermeasuresWatermatchedirrigationEfficient water source subsystem for agricultureWatersavingwellalterwaterSewageofsystemInterfaceestablishmentFivewaterwatersystemRainfed‘Watersaving agriculture’ is a plex system involving agronomic and hydraulic engineering techniques in the integrated management of water, soil and crop resources. Only when watersaving agriculture is considered as an integrated system can prehensive watersaving measures be properly evaluated and applied. pDiscussions of some ideas of watersaving:Agriculture Watersaving systemsRational exploitation and utilization of water resourcesIrrigation engineering and techniquesAgronomic watersaving practicesWatersaving management measuresAgriculture Watersaving System plexFour subsystems context 3. agricultural watersaving system Rational exploitation and utilization of water resourcesEffective use of precipitationFivewater interaction mechanismsUtilization of low quality waterRainwaterSoilAtmosphere interface control3. agricultural watersaving system evaporationdecreasemulcingmaizeevaporationdecreasemulchingevaporationSummer maizeWinter wheatWheatonstrawwheatTo adopt lower limit index by limited irrigationEffectsindexMatureGrainfillingAnathesisStemelongationRecoveragePredormancyGrowingwaterGrainfillingSpinningStemelongationSeedlingGrowingindexcontrol60%65%70%65%55%SoilRootSoilcontroln Different varieties have WUE differences from 15% to 20%， from which a water saving va