- 1. International Conference on Climate Change and Food Security, November 8, 2011 Impacts of agro-drought on grain production in ChinaZhihao Qin, PhD, professor Institute of Agro-Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081, China Email: email@example.com
2. Drought in YunnanThe contents• Background• Objectives• Methodology• Results and analysis• Conclusion 3. Climate in ChinaThe climate of China is complex, diverse, and unique, with a monsoon-controlled pattern showing clear latitudinal and longitudinal differentiation. Theannual rotation of four seasons (spring, summer, autumn, and winter) withcoincident heat and rainfall is a well-known feature of Chinese climate.Formation of Chineseclimate is subject to theinteraction of four mainregimes that governclimatic dynamics in China:subtropical monsoon,tropical monsoon,plateau monsoon, I West wind circulation regimeand west-windII Subtropical monsoon regime III Tropical monsoon regimecirculation. VI Equatoric monsoon regime V Tibetan Plateau monsoon regime 4. Drought is the mostpowerful natural forceshaping impact onagriculture. In China drought is catastrophic: frequent, seriousEach year drought occurs invarious parts of China, with anaverage acreage of 20-25 MhaAgriculture in China:Arable land 100 M haCropping area 155 M haGrain area 100 M haGrain production 500 M t 5. Climate in China is a typical monsoon pattern. WithrainfallDrought has been a frequent climatic event in China.2007 drought in Guangxi and Hunan. 2008 in southwestand northwest ChinaSince 2009, China has been continuously attacked bysevere drought events, with 2009 in north China plain,2010 in southwest China, and this year 2011 in middleYangtze River Basin and southwest China.2011 is a big drought year in China, spring and summer,drought. It is said that this drought was the biggest withinthe last 60 years. 6. Drought intensity for 2001-2005 Heilongjiang Jilin LiaoningXinjiangInner Mongolia 1 2Hebei 4 ShanxiShandong Qinghai Gansu Shaanxi Henan Jiangsu Anhui3 Tibet SichuanHubei 25% 6 Chongqing 7. Drought monitoring in ChinaAugust 2005 May 2005 Based on MODIS data 8. 图2全国旱情遥感监测(2009年3月下旬) MODIS + 降水 监测结果 特旱 正常 重旱 湿润 中旱 过湿 轻旱 云说明：旱情等级划分，见表1的注解 9. 图1 全国耕地旱情遥感监测(2009年5月中旬) 特旱正常 重旱湿润 中旱过湿 轻旱云 非耕地 说明：旱情等级划分，见表1的注解 10. Objective of the studyEconomically drought reduces the productivity of cropland tothreaten food security in a country like China with giantpopulation and relatively limited cropland resources.Environmentally water shortage and high temperature as aresult of drought can alter soil organic carbon (SOC) dynamicsto affect climate changes in regional and global scales.Objective: to quantify drought’s impact on grainproduction and food security in China. 11. MethodologyTo link drought with food security and climate change DroughtWater and temperature stressProductivity declineBiomeResidues, manure, CO2, CH4,Productionleaching Soil fertility SOC change Food securityClimate change 12. Data for the analysisAvailable statistic data on drought in China• Drought statistics in ChinaOnly cropping acreage under drought effects are available, with three levels of severity:Slight drought: 10-30% of productivity declineModerate drought: 30-50% declineSevere drought: >50% of productivity decline 13. Drought intensity indexPercentage of drought area to total cropping acreageTaking moderate drought as unityw1 Ai1 + w1 Ai 2 + w3 Ai 3 DI i =Aitwhere DIi is the drought intensity index for province i; Ai1, Ai2 andAi3 are the cropping acreages under drought at slight, moderate andsevere levels, respectively, in province i; Ait is the total croppingacreage in province i; and w1, w2 and w3 denote the weights ofdrought at slight, moderate and severe levels, respectively.Taking moderate drought as unity, we give w1=P1/P2=0.45, w2=1,and w3=P1/P2 =1.78 in the study. 14. Drought-induced loss of grain production Computation according to cropping structurennFd = ∑Fdi =∑[Ri Ai1Yi (1− P ) + Ri Ai2Yi (1− P ) + Ri Ai3Yi (1− P )] 123i=1 i=1where i denotes province i; n is total number of provinces (n=30); Fdiis drought-caused food production loss in province i; Ri is the fractionof grain cropping area to the total cropping area in province i; Ai1, Ai2and Ai3 are the cropping areas under drought at slight, moderate andsevere levels, respectively, in province i; Yi is the yield of graincropping in province i; and P1, P2 and P3 denote the rates of yielddrop under drought at slight, moderate and severe levels, respectively.The rates can be determined as the conservative medians, i.e. P1=20%,P2=45% and P3=80% 15. Drought impact indexTo represent the impact of drought on grain production, aspercentage of drought-induced loss to the total production FdRd =×100% FpFwhere Rd represents the impact of drought on food security,and Fp is the food production without drought. 16. Procedures for analysis of drought’s impacts on grain production and climate change in China.Statistic data The supportedFood productionDrought dataCropping & other data databases DNDC model Models on drought & Models on drought & Cropland SOCfood relationship SOC relationshipDrought’s impact onDrought’s impact onfood productionSOC dynamicsEvaluation of drought’s impacts 17. Results and analysis• Drought attack on agriculture in China in recent years• Spatial variation of drought intensity in China• Annual loss of grain production due to drought attacks• Impact of drought on food security in China• Relationship between drought intensity and its impact on food security in China 18. Change of cropping areas under various Arable land: 130 Mhalevels of drought attack Cropping acreage: 155Mha20000Slight (a)17500 ModerateSevereDrought acreage (Kha)150001250010000750050002500 01990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 Year 19. Change of agro-drought intensity in China 26 24 22Drought intensity ( %) 20 18 16 14 12 10861990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005Year 20. Drought Intensity(a) 1990-1995 (b) 1996-2000(c) 2001-2005 (d) 2005 25% 21. Actual and potential food productions in ChinaDifference betweenactual and potentialfood productions inChina 22. Impact of drought on food security of China10 9 8Impact ( %) 7 6 5 4 3 2 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 Year 23. Drought-induced food production loss (a) 1990-1995(b) 1996-2000 (c) 2001-2005(d) 2005 2000Kt 24. Spatial variation of drought impact on food production(a) 1990-1995 (b) 1996-2000(c) 2001-2005 (d) 2005 10% 25. Relationship between drought-induced food production loss and drought intensity in China55 (a)5045y = 1.9747x + 0.578140 2 R = 0.9784Loss (mt)353025201510 5 7 9 11 13 1517 19 21 23 25 27 Drought intensity % 26. Relationship between drought’s impact on foodproduction loss and drought intensity in China 11(b) 109 y = 0.3838x + 0.32658 2R = 0.9933Impact %7654325 7 9 11 13 1517 19 21 23 25 27 Drought intensity % 27. ConclusionEach year 25-30 Mha of cropping land were under drought attack.Drought intensity was 13.8% on average between 1990-2005, with maximumof 25% and minimum of 6%.Drought induced 28 Mt of grain production loss, shaping an impact of 6% tototal grain production in China, shaping an impact of 3% inminimum and 10% in maximum on food security in China1996-2000 had the severest drought, with an intensity of 15.11% on averageand an annual food production loss of 32Mt, leading an impact of 6.1%.Greater impacts of drought on grain production were observed in NortheasternChina and Northwestern China regions, including Shanxi, Shaanxi, JilinHeilongjiang and Inner Mongolia provinces.Quantitatively an increase of 1% in drought intensity might lead to 2 Mt offood production loss, and an impact of 0.4% on total grain production. 28. Thank you!