1、Symposium on Environmental Changes and Efficient Use of Agricultural Resources, (Oct. 2122, 2011, Shijiazhuang, China)Agricultural water saving studies for a sustainable water management in the North China Plain (NCP)Changming LiuAgricultural Resources Research Center, CASKey Lab, IGSNRR, CAS, Water
2、 Science College BNU Outline p Major features of NCPs water resourcesp Main Water issues: rapid social-economic development and climate changep Agricultural water-saving: the highlightsp Discussions of some ideas of water-savingp Agricultural water-saving: Policy & Countermeasuresp Major features of
3、 NCPs water resourcesAnnual precipitation in mmAverage annual precipitation from 1951 to 2008 The NCP: in the semi-arid & semi-humid region. Annual precipitation around 350 and 800 mm The monsoon season (June to September) contributes more than 80% of annual rainfall Major features of NCPs water res
4、ourcesPotential evapotrnspiration in mmAnnual Potential evapotrnspiration in the NCP is high varies between 796 and 1257 mm resulting in much water loss Average annual Potential evapotrnspiration from 1951 to 2008 p Major features of NCPs water resourcesAridity indexThe aridity index varies from 1.0
5、 to 3.2. Its in the climate transition zone. pMajor features of Chinas water resourcesAnnual evapotraspiratiom in mmAverage annual evapotrnspiration from 1951 to 2008 calculated by the Budyko hypothesis.pMajor features of Chinas water resourcesAnnual runoff in mmSharp decline river flows into the se
6、aPer Capita water amount pMajor features of Chinas water resources Water Consumption to avalaible water resources in % in ChinaAfter Dr Shao Yisheng，Ministry of ConstructionWater use / water availability in %p Major features of NCPs water resourcesSummary NCP is the most water shortage area in China
7、 as per capita water 300 m3 only. Total water withdrawal: 37 km3 / a(2009) exceeding available water Overdrawing groundwater has resulted in aquifer water depletion as a water crisis Agricultural water use about 25.3 km3 / a(2009), making up about 68.5% of total withdrawal Water-saving is very cruci
8、al Attribution: Water stress from rapid development: Current GDP growth is speeding up incuding NCP regionp Main Water issues: Rapid development Water stress from increased water demand: increased water consumption per capita.p Main Water issues: Rapid development Population density of China (Xu et
9、al.)The NCP has a population of about 0.15 billion, accounting for 12% of Chinas total population.The daily water consumption per capita has been increasing from less than 0.03 m3 in 1959, to more than 0.10 m3 in 1995, and to more than 0.20 m3 in 2000 Attribution: Water stress from increased water d
10、emand. Irrigation demand approached a limit.p Main Water issues: Rapid development Irrigated area in NCP from 1949 to 2008Attribution: Climate change impact as warming upp Main Water issues: Climate change lTemperature increase: 1.1 for last 50 years in China as an averagelTemperature in the NCP inc
11、rease about 1.7 from 1960 to 2010.Increase in temperature from 1951 to 1999 (Wang et al.) Temperature in northern China increased more serious than that in southern ChinaAttribution: impact of precipitation declinep Main Water issues: Climate change Observed change in annual precipitation from 1960
12、to 2009 by 753 national stationsAnnual precipitation anomalies in the NCP from 1955 to 2009. The The average annual precipitation during was 567.9 mm from 1955 to 1979, while that was 503.5 mm from 1980 to 2009, decreased about 11.4%.Attribution: Increase in drought frequency p Main Water issues: Cl
13、imate change In 20102011, 60 years record drought hit Northern ChinaThe distribution of Drought in the spring of 2011Wheat seedings that have withered in NCPConsecutive 82 days without rain in Beijing, the longest period without precipitation in 60 yearsThirstyDry landscapeSharply increased water co
14、nsumption in the NCP lead to the dramatic decrease in streamflow into the Bohai sea in last half century.Annual streamflow into the sea decreased dramatically, from 16.10 km3 in 1960s to 1.62 km3 during the years 2000 to 2008, decreased about 90%.The streamflow into Bohai sea in the last half centur
15、yGroundwater depletion in the regions of the US, Europe, China and India and the Middle East for the year 2000 (mm a1).- Wada et al.,2010, Geophysical Research Letters. Groundwater depletion - a worldwide issueThe NCP is one of the four regions which have serious issues of groundwater depletionNCPGr
16、oundwater overdraft: sever in NCP The North China Plain is the major consumer of groundwater, accounting for 44% of the whole countrys groundwater use.The annual groundwater use for China was about 105.6 billion m3, among which 92.21 billion m3 (87.3%) was consumed by northern China. The North China
17、 Plain has become one of the most overexploited regions in the world Annual groundwater withdrawal averaged from 1997 to 2008 in China(data come from the Chinese Ministry of Water Resources)p Main Water issues: Groundwater depletion Ground fissure resulting from overdraft of groundwater in the North
18、 China Plain (in Hebei province）The depth to groundwater was 11.06 meters in 1978, and has been subsequently reduced to 36.12 meters in 2009, with an average annual decline rate of 0.81 meters Long-term (the year from 1972 to 2009) data of groundwater level has been recorded at the Luancheng Nationa
19、l Station (located in the North China Plain), a member of Global Terrestrial Observation System (observed data come from Chinese Academy of Sciences)groundwater level fluctuated with irrigation seasonGroundwater level desceningObserved at Luancheng stationSummary: to save groundwater in the NCP is v
20、ery urgent p Agricultural water-saving: A highlightWater-saving is core of rational water management To adapt to climate change To realize highest potential use of available water To increase water economy with high benefit To control blind development of regional water resources and promote water d
21、emand management To maintain eco-environment against degradation To foster participation management institutionsWater-saving”Killing Many Birds With One Stone”！Water saving is the best for adaptation to climate change impact on water resources p Discussions of some ideas of water-saving:1.Field wate
22、r cycle / five water interactions 2. interface control of water fluxes3. agricultural water-saving system +11098765432Five water interactionTransformationof hydro-statesAAirPlantSoilAquiferSurfacePVRGS1.Field water cycle / five water interactions A coupling subsystem of water interaction(交换的系统耦合交换的系
23、统耦合)PRSGVP1P / RP / SP / GP / VRR / P1R / SR / GR / VSS / PS / R1S / GS / VGG / PG / RG / S1G /VVV / PV / RV / SV / G1)!( !nmnmCnmmm: Elements = hydro-state number or sub-system numbern: combination = number of coupling subsystemsm(n = 2), matrix: n = 2, combination = 10: (1)P-R(降雨径流降雨径流)； (2)P-S(有效
24、降水有效降水)； (3)P-G(地下水降水补给地下水降水补给)； (4)P-V(植物截留降水植物截留降水)； (5)R-S(土壤水对径流影响土壤水对径流影响) (6)R-G(地表水地下水关系地表水地下水关系) (7)S-G(渗漏与地下水上升渗漏与地下水上升)；(8)R-V(径流过程的初损径流过程的初损) (9)G-V(植物利用地下水植物利用地下水)； (10)G-V(根系吸水根系吸水)。 n =3，combination = 10： (1)P-R-S(考虑前期土壤水的降水径流关系，考虑前期土壤水的降水径流关系，API模型模型)； (2)P-R-G(三水转化三水转化)； (3)P-R-V(降水径
25、流的初损降水径流的初损)； (4)P-S-G(降水入渗补给地下水降水入渗补给地下水)； (5)S-V-P(水在土壤水在土壤-植物植物-大气系统中的传输或大气系统中的传输或SAPC系统系统)； (6)G-V-P(地下水地下水-植物植物-大气系统，地下水垂直排泄大气系统，地下水垂直排泄)； (7)G-S-P(三水转化三水转化)； (8)G-V-R(地下水与地表水关系的植物影响地下水与地表水关系的植物影响)； (9)V-S-G(植物对土壤水与地下水的影响植物对土壤水与地下水的影响)； (10)V-S-R(植物对土壤入渗与径流的影响植物对土壤入渗与径流的影响)。 n = 4，combination =
26、 5： (1)P-R-S-G (四水转化四水转化)； (2)P-R-S-V (植物与土壤对降水径流影响植物与土壤对降水径流影响)； (3)V-R-S-G (植物对三水转化的影响植物对三水转化的影响)； (4)V-P-R-G (植物对降水径流与地下水的影响植物对降水径流与地下水的影响)； (5)G-S-V-P (考虑地下水影响的考虑地下水影响的SAPC系统系统)。 n = 5，combination = 1： P-V-R-S-G (五水转化五水转化), water interaction of five sub-systems (five hydro-states)。2. interface c
27、ontrol of water fluxes IGBP- BAHC, 1997Expanded “SPAC” Basic equation:tzDzkzS z t,Boundaries: Air and aquifer To couple air water and groundwater IA=0.4Ym+0.4WUE+0.1(Rs+Tr)+0.1DI Detecting physiological and ecological index synthesisYm: grain yieldWUE: water use efficiencyRs: stoma resistanceTr: tra
28、nspiration rateDI: drought indexSoilWaterAtmos.W a t e r &EnergyTransferAtmosphereRadiationPARReflective radiation Direct radiationWind speedTemperature, humidityDifference of Ta and RH PrecipitationVegetationInterceptionAlbedoBiomassLAISpatial distr. of leavesVegetation heightLeaf water potentialSt
29、omatal conductanceRootRoot water potentialRoot semi-diameterRoot length and weightDistribution of rootsRoot depthSoil Root water potentialSoil heat fluxWater infiltration Soil evaporationPhysical charactersSoil water charactersSoil water contentSoil matrixGroundwater EvapotranspirationntionEvaporati
30、onTranspirationRoot water uptakemovementnWater movementEnergy change and tension for water transferG r o u n d w a t e r rechargeVariation of groundwaterComplexity SystemsATMCROPSoilG.WG - SPACRunoffInfiltrationLateral FlowSoil Layer 1Soil Layer nEvaporationTranspirationInterceptionOverstoreyUnderst
31、oreyTranspirationGround SurfaceSoil moistureETseepageWater balance+ GroundwaterRstemRrootRleafAtmosphereSPAC systemVarieties heredityReduce water lossIrrigation varieties(Air-leaf)mulching(Air-soil)Uptaking(Soil-root)+precipitationThrough-fullinterface controlIA=0.4Ym+0.4WUE+0.1(Rs+Tr)+0.1DI 综合分值 品种
32、 最高产量 WUE 蒸腾强度 气孔阻力 叶水势 抗旱系数 加权平均 占 最大 位次 6203 93.10 93.37 92.09 91.64 100.00 92.52 93.79 96.60 3 6172 100.00 96.12 88.26 91.92 99.38 92.51 94.70 97.54 2 莱3279 79.60 98.58 84.20 100.00 91.91 100.00 92.38 95.15 5 4185 93.10 93.37 89.06 81.78 88.33 92.69 89.72 92.41 7 6365 99.43 100.00 100.00 98.44 92
33、.44 92.22 97.09 100.00 1 烟优 361 94.11 92.43 92.08 85.31 96.95 92.92 92.30 95.07 6 9905 93.68 94.89 89.60 83.65 96.36 97.36 92.59 95.37 4 Measurements of physological indexes of various varieties for water saving optios Leaf-Atmosphere interface controln Different varieties have WUE differences from
34、15% to 20%，from which a water saving variety gene can be selected for controlling higher transpiration.n Wheat： 4185、 6365、Shixin733 n Corn： Zhengdan958，Laiyu2，Yedan20 Root-Soil interface control60%65%70%65%55%Soil water index0.1496 0.2061 0.3645 0.1116Sensitive indexMature Grain-fillingSpinningStem
35、-elongationSeedlingGrowing stageSummer maizeSummer maize50%60%60%65%55%60%Soil water index-0.0870.10160.27210.3145-0.12130.0712Sensitive indexMatureGrain-fillingAnathesisStem-elongationRecoveragePre-dormancyGrowing stageWinter wheatWinter wheatTo adopt lower limit index by limited irrigationEffects
36、of straw mulching on soil evaporationSummer maizeWinter wheatWheat straw mulching can decrease soil evaporation 40-50mm；Summer maize straw mulcing can decrease soil evaporation 39.7mm. Soil-Atmosphere interface controlb051015202530起身- 拔节拔节- 孕穗孕穗- 开花开花- 灌浆灌浆- 成熟土壤蒸发（m m ）覆盖不覆盖3. agricultural water-sa
37、ving system Water-saving agriculture is a complex system involving agronomic and hydraulic engineering techniques in the integrated management of water, soil and crop resources. Only when water-saving agriculture is considered as an integrated system can comprehensive water-saving measures be proper
38、ly evaluated and applied. pDiscussions of some ideas of water-saving:Agriculture Water-saving systemsRational exploitation and utilization of water resourcesIrrigation engineering and techniquesAgronomic water-saving practicesWater-saving management measuresAgriculture Water-saving System complexFou
39、r sub-systems context 3. agricultural water-saving system Rational exploitation and utilization of water resourcesEffective use of precipitationFive-water interaction mechanismsUtilization of low quality waterRainwater harvesting systemRain-fed agricultureSoil water reservoir establishmentFive-water
40、 interaction systemInterface processesUtilization of brackish waterSewage utilization alter creatingConjunctive well &canal irrigationEfficient water source subsystem for agricultureWater-saving agronomic measuresWater-matched productionBiological water saving technologyWater-saving irrigation schem
41、eWater-matched agricultural structureWater-matched plantingWater saving biological basisSoil moisture conservancyFertilizer applicationLimited irrigationWater saving breeding Regulated deficit irrigationControlled alternative irrigationMulching techniqueTillage measureAgronomic measures subsystem Wa
42、ter-saving engineering and technical measurerWaters conveyance worksWater-saving irrigation techniquesAssociatied canal systemsLined canal (cleek proof)Water conveyed through low pressure pipeWater conveyed through surface pipe Drip irrigationSprinkler irrigationSeeping irrigationRational surfaceBor
43、der irrigation with small plotsIrrigation on the filmIntermittent irrigationDitch irrigation (fine flow)Alternative ditch irrigationengineering and technical measures subsystem Water-saving management subsystemInstitutions规章制度与节水法规组织机构管理政策OperationTech-economyEco-environment多种经营综合作用水量调控、调度量水设施监测农田生态
44、平衡水源保护（水量、水质）工程维护、改建配水计划自动化控制技术经济核算水价与水费制度节水措施推广应用人员编制Managt. PolicyOrg. departmentPersonnelLegislationWater fee/priceTech popularise economic accountingdiversified economyAuto. control Water allocationWater measuringMaintaining struc.Water regulating Monitoring protectionEnvironment Ecology Achieve
45、ments obtained by system integration at Luancheng Station in NCP Water-saving system integration demonstrated a highest benefit as integration of agronomic and irrigation tech.:l Water-saving quantity: 1500 m3 / ha.l Grain yield: winter wheat + corn = 15 t / ha.l Earning increase: 1500 RMB / ha. p A
46、gricultural water-saving: Policy & CountermeasuresMajor understandingAgricultural water-saving is of great significance to ensure food security for China with its largest sized population of worlds 22%. We will be facing a great challenge to meet 1.5 billion population in about 30 years to come. Maj
47、or understanding1. Food security is subject to water supply;2. Agriculture uses the most amount water & dominant consumer; 3. Agriculture can use all-kind of water, including “green and blue waters”and recycling water and unconventional water as well; Major understanding4. Water saving is complex sy
48、stems & needs multidisciplinary technologies;5. Water saving has great potential;6. Agriculture widely uses all-kind of water, including “green and blue waters”and recycling water as well; Major understanding7. To resolve water shortage problem, biotech has a prosperity advantages:(1) high reliabili
49、ty for water saving; (2) high efficiency; (3) high capability (4) high applicability and (5) low cost compared with water diversions; Strategic measures:1. To manage water resources is an extremely important issue. There is a pressing need to move away from the past practices of unplanned irrigation
50、-infrastructure and move towards consideration of water governance for water renew-ability. Strategic measures:2. To deepen scientific knowledge and transfer the water-saving techniques to farmers more widely;3. To iTo establish marketing mechanisms for water-saving agriculture and to promote the in
