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GROUP 2, SESSION A: CARBON OR WATER FOOTPRINTS, SOIL, BIODIVERSITY 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
58. Water footprints of wheat and maize: comparison between China’s
main breadbasket basins
Jing Huang 1,2 , Bradley G Ridoutt 2 , Feng Huang 3 , Fu Chen 1,*
1 China Agricultural University, College of Agriculture and Biotechnology, Beijing 100193, China, 2 Commonwealth
Scientific and Industrial Research Organisation (CSIRO), Sustainable Agriculture National Research
Flagship, Private Bag 10, Clayton South, Victoria 3169, Australia, 3 China Agricultural University,
College of Resource and Environmental Sciences, Beijing 100193, China, * Corresponding author. E-mail:
chenfu@cau.edu.cn
As the most populous country in the world, China’s food security has become an issue of broad concern. A
critical factor which threatens food production is water scarcity. In recent decades, the water-scarce northern
part of China has become the most important agricultural production area, supported in small part by water
transfers from the South. Substantial volumes of food are being transferred from the water-scarce north to the
water-rich south. In the context of China’s food security, this complex arrangement has been the focus of
much debate. However, science-based evidence to support an environmentally-sustainable increase in
China’s food production is rarely found in the literature.
This study compares the water footprints of cereal production (wheat and maize) in China’s main breadbasket
basins. Water footprints were calculated using an LCA-based water footprinting method (Ridoutt and
Pfister, 2010) which uses a Water Stress Index (WSI; Pfister et al., 2009) to express the environmental relevance
of water use. The water footprints are presented in the units H2Oe (equivalent), where 1 L H2Oe represents
1 L of consumptive freshwater use at the global average WSI.
Wheat grown in the Huang and Hai basins had much higher water footprints (1,262 L H2Oe kg -1 ) compared
to wheat grown in the Chang basin (31 L H2Oe kg -1 ). The water footprints of maize grown in the Huang,
Huai and Hai basins (515 L H2Oe kg -1 ) were also much higher than maize grown in the Chang and Songliao
basins (35 and 44 L H2Oe kg -1 respectively).
These results demonstrate a huge spatial differentiation of water use for cereal production in China’s main
breadbasket basins. It is suggested that the variability in crop water footprint between production systems
should be taken into consideration in strategic decisions related to China’s food production. National-scale
cropping pattern adjustment and technological upgrade at the basin level are considered as important interventions
to alleviate water stress from agriculture.
References
Ridoutt, B.G., Pfister, S., 2010. A revised approach to water footprinting to make transparent the impacts of
consumption and production on global freshwater scarcity. Global Environ. Chang. 20, 113-120.
Pfister, S., Koehler, A., Hellweg, S., 2009. Assessing the environmental impacts of freshwater consumption
in LCA. Environ. Sci. Tech. 43, 4098-4104.
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