China's hidden water footprint

July 07, 2014

China's richest provinces have an outsized environmental impact on the country's water-scarce regions, according to new research from the International Institute for Applied Systems Analysis (IIASA) and the University of Maryland.

Many developed regions in China are not only drawing from their own water resources but also contributing to water depletion in other water-scarce regions of the country through imports of food and other water-intensive goods, according to the new study published in the journal Environmental Science & Technology. This has environmental impacts and potential future impacts on water availability for the entire country.

The new study used the concept of "virtual water," an economic concept used to track water flows through trade, to track how water is traded through agricultural products and other goods that require water to produce. But while previous studies of water flows had treated all water equally, the new study accounts for water scarcity.

"When goods and services are exchanged, so is virtual water," explains IIASA and University of Maryland researcher Laixiang Sun, a study co-author. "For example, it takes about 1,600 cubic meters of actual water to produce one metric ton of wheat. When a country or region imports a ton of wheat instead of producing it domestically, it saves most of that."

In China, water resources are distributed unevenly, with ample water in the wealthier southern region, and scarce water in most northern provinces. The study shows that trade between these water-scarce regions tends to draw more sharply on water resources in the less developed, poorer regions. For example, the provinces of Shanghai, Shandong, Beijing, and Tianjin import large amounts of virtual water at the expense of less-developed provinces such as Xinjiang, Inner Mongolia, and Hebei.

"Importing water-intensive goods from one water-scarce region to another doesn't solve the problem of water scarcity--it just shifts the pressure to other regions," says co-author Klaus Hubacek, a researcher at the University of Maryland and an alumnus of the IIASA Young Scientists Summer Program.

The study also examined the impact of international exports on water resources, showing that production of international exports in China's top exporting regions also draws on water resources in water-scarce northern provinces.

Sun adds, "With the fast growth of China's economy, and increasing urbanization, this trend is likely to continue in the next few decades."

Recognizing the problem of water scarcity, China has launched a multi-billion dollar water transfer project to divert water from the South to the North. But the authors suggest that replacing imports from the North with goods produced in the South could be a more efficient solution to the problem.

The researchers say that their new study lays the groundwork for smarter water resource management. Says Sun, "This is the first study that incorporates water consumption, water scarcity, and ecosystem impacts into an analysis that conveys the pressures on water resources. Using virtual water as a policy tool only makes sense if you take water scarcity into account."
-end-
Reference

Feng, Kuishuang, Klaus Hubacek, Stephan Pfister, Yang Yu, Laixiang Sun. 2014. "Virtual Scarce Water in China." Environmental Science and Technology, http://dx.doi.org/10.1021/es500502q.

For more information contact:

Laixiang Sun
IIASA Senior Research Scholar
Water Program
+43(0) 2236 807 543
sun@iiasa.ac.at

Klaus Hubacek
University of Maryland
+1 301-405-4567
hubacek@umd.edu

Katherine Leitzell
IIASA Press Office
Tel: +43 2236 807 316
Mob: +43 676 83 807 316
leitzell@iiasa.ac.at

International Institute for Applied Systems Analysis

Related Water Articles from Brightsurf:

Transport of water to mars' upper atmosphere dominates planet's water loss to space
Instead of its scarce atmospheric water being confined in Mars' lower atmosphere, a new study finds evidence that water on Mars is directly transported to the upper atmosphere, where it is converted to atomic hydrogen that escapes to space.

Water striders learn from experience how to jump up safely from water surface
Water striders jump upwards from the water surface without breaking it.

'Pregnancy test for water' delivers fast, easy results on water quality
A new platform technology can assess water safety and quality with just a single drop and a few minutes.

Something in the water
Between 2015 and 2016, Brazil suffered from an epidemic outbreak of the Zika virus, whose infections occurred throughout the country states.

Researchers create new tools to monitor water quality, measure water insecurity
A wife-husband team will present both high-tech and low-tech solutions for improving water security at this year's American Association for the Advancement of Science (AAAS) annual meeting in Seattle on Sunday, Feb.

The shape of water: What water molecules look like on the surface of materials
Water is a familiar substance that is present virtually everywhere.

Water, water everywhere -- and it's weirder than you think
Researchers at The University of Tokyo show that liquid water has 2 distinct molecular arrangements: tetrahedral and non-tetrahedral.

What's in your water?
Mixing drinking water with chlorine, the United States' most common method of disinfecting drinking water, creates previously unidentified toxic byproducts, says Carsten Prasse from Johns Hopkins University and his collaborators from the University of California, Berkeley and Switzerland.

How we transport water in our bodies inspires new water filtration method
A multidisciplinary group of engineers and scientists has discovered a new method for water filtration that could have implications for a variety of technologies, such as desalination plants, breathable and protective fabrics, and carbon capture in gas separations.

Source water key to bacterial water safety in remote Northern Australia
In the wet-dry topics of Australia, drinking water in remote communities is often sourced from groundwater bores.

Read More: Water News and Water Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.