V IRTUAL W ATER AND W ATER I SSUES IN C HINA TANG QIUHONG
Virtual Water and Water Issues in China 1.Water issues in China. 2.Virtual Water and water resources management. 3.Some problems in WR assessment.
1. Water issues in China Water resource per capita (population of 1997) Unit: m 3 /capita 4832m 3 /capita 500m 3 /capita 2369m 3 /capita
1. Water issues in China Water resource per capita (1997) Unit: m 3 /capita
1.1 Inland river area Water resource: 4832m 3 /capita [1] Tarimu River Upstream Downstream Data Reclamation increases. (Especially, in Xinjiang) Water use at upstream increases. It causes water scarcity downstream (For example, Tarimu River)
1.2 Yellow River area(Huaihe, Haihe) Water resource: 656/389/225m 3 /capita [1] Rapid increases in water use though cultivated land area decreases. (Maybe it is because of increases in irrigated area at downstream: Map)Map Decreases in discharge in to 1990s though precipitations change little. (In Hebei province, precipitation 2.7%, but discharge 25%, water resource 14%, data set [2] )
1.3 Yangtse River area Water resource: 2369m 3 /capita [1] Commonly, Yangtse river has no water scarcity problem (flood control, fight waterlogging). Cultivated land area decreases because of the economic growth.
1. Review main water issues in China Flood, waterlogging Cultivated land area decreases Reclamation Water use in upstream Rapid increases in water use Decreases in discharge Without water quality problems! 4832m 3 /capita 500m 3 /capita 2369m 3 /capita
2. Virtual Water and WR management WR= W a +W i +W e W a : water for agriculture; W i : water for industrial; W e : water for environment For an isolated research area (control): WR+t =(W a +t a )+ (W i + t i )+(W e +t e ) t= t a + t i + t e Import / Export Real Water t (Inter-catchment water transfer): WR + v = … WR =(W a -v)+ (W i + v i )+(W e +v e ) v= v i + v e Import / Export Virtual Water v : ? 1.Import VW will not change the WR. Import / Export VW will hurt /enhance local agriculture. 2.Import VW != enhance industry (depend on industry demand, v i )
2.1 WR management in inland river case Why have water scarcity problem: Reclamation Water use in upstream WR =(W a - v)+ (W i + v i )+(W e + v e ) v= v i + v e (Virtual water export: 65.7*10 8 m 3 [3] ) 1.Industry demand, v i, is not very much in Northwest China. 2.Export v hurt the environment v e (a seize the water for e) 3.Reduce export v will hurt agriculture, but will not get benefit from industry v i 1.Improve water use efficiency. Reduce the water use but keep VW export (protect agriculture, farmer). 2.Improve industry, industrial urbanization, v i, reduce VW export. 3.Water right. (upstream should not use all the water) ACTIONS:
2.2 WR management in Yellow river case Why have water scarcity problem: Rapid increases in water use Decreases in discharge WR=(W a -v)+(W i +v i )+(W e +v e ) v= v i + v e 1.Water in short supply (population increase, economy increase). 2.a,i and e are hurt. 1.Improve water use efficiency. Use same water, do more things. 2.Give up. (Import VW [repress agriculture] or encourage people to move out) 3.Change WR. (Import real water!) ACTIONS: (Water resource: about 500m 3 /capita [1] ) WR+t=(W a +t a )+(W i + t i )+(W e +t e ) t= t a + t i + t e
2.3 WR management in Yangtse river case Water issues: Flood, waterlogging Cultivated land area decreases 1.Agriculture is hurt by industry, not because of WATER, but land. 2.Much water run to waste (flow to the sea). 1.Export VW. (Increase irrigated area, 48.2%, data 1998 [4] ) 2.Export real water. ACTIONS: WR=(W a -v)+(W i +v i )+(W e +v e ) v= v i + v e WR+t=(W a +t a )+(W i + t i )+(W e +t e ) t= t a + t i + t e
2. Review VR and WR management Red: existing circumstance Blue: management VW flow real water flow land increase, export VW land decrease, move more water to i, reduce VW export a,i,e are short of water repress a, import VW and real water water waste (to the sea) Export VW and real water
3. Some problems in WR assessment 3.1 Limitation of renewable WR definition 4800m 3 /capita? 500m 3 /capita 2300m 3 /capita precipitation mm/a mm/a About 1000mm/a aie 4800m 3 /capita ai e 2300m 3 /capita [5]
3.2 VW Trade can save WATER Res [6] ? Water Food WR North AmericaSouth America != The assumption is: WR in NA is same as WR in SA. Deny the WR distribution problem. Underlying assumption is: If we can transport Real Water form SA to NA, we can get more food (benefit). From the eyes of management, VW trade can not save WR, (it can only save virtual water?) Transfer Real Water Upstream Downstream low efficiency high efficiency+ land, other social conditions Virtual Water
3.3 VW Strategy WR =(W a -v)+ (W i + v i )+(W e +v e ) v= v i + v e Import / Export Virtual Water v : InvestmentProfit/ Benefit Value(v)Benefit(i) + Benefit(e) -Loss(a) Benefit(i): How much water does industry demand? If we know it, we can calculate Benefit(i). Benefit(e): How to calculate the value of environment? Mr. Jiang has do some research on it [7][8]. Benefit! Scientists tell us an object, engineers tell us to reach the object with maximize profit. A good engineer should be a good sociologist first.
Please move your eyes to China! Thank you for your attention!
Reference [1] United Nations Economic and Social Commission for Asia and the Pacific (ESCAP) (1997): Study on Assessment of Water Resources of Member Countries and Demand by User Sectors: China - Water Resources and Their Use. New York, p. 9 [2] 黄河水资源情势分析, 贺伟程, 中国水情分析研究报告, 2000 第 7 期. (Chinese) Water resources situation in Yellow River, He Weicheng, Report of water issues in China, 2000 (7). [3] 虚拟水:中国干旱区水资源管理的新思路, 程国栋, 水利专报. (Chinese) Virtual Water: A new water resources management way in arid area in China, Chen Guodong, Special report of water issues. [4] 加强南方水利建设, 提高粮食自给能力, 苏人琼 等, 中国水情分析研究报告, 2000 年 12 月第 34 期. (Chinese) Improve the irrigation works in south China, strengthen food self-support, He Weicheng, Report of water issues in China, (34). [5] Rockstr ö m, J., L. Gordon, C. Folke, M. Falkenmark, and M. Engwall Linkages among water vapor flows, food production, and terrestrial ecosystem services. Conservation Ecology 3(2): 5. [online] URL: [6] T. OKI, M Sato, et al. Virtual water trade to Japan and in the world. [7] 水资源价值论, 姜文来, 北京 : 科学出版社, (Chinese) Review of value of water resource, Jiang Wenlai, Beijing: Science press, [8] 水资源价值模型研究, 姜文来, 资源科学, 1999(1). (Chinese) A study on water resource value model, Jiang Wenlai, Resources science: 1999(1). Acknowledge Most of the data come from 中国可持续发展信息网 - 水资源与水环境共享网站 (Chinese, Sustainable Development in China- Shared data in water resource and water environment, URL: ) and Can China Feed Itself? Homepage (author: Gerhand K. Heilig URL: ).
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Cultivated area Grain output Cultivated area G rain output Back
Blue water & Green water Liquid (blue) water flow is the total runoff originating from the partitioning of precipitation at the land surface (forming surface runoff ) and the partitioning of soil water (forming groundwater recharge). Water vapor (green) is the return flow of water to the atmosphere as evapotranspiration (ET), which includes transpiration by vegetation and evaporation from soil, lakes, and water intercepted by canopy surfaces (Rockström 1997). Back