ABSTRACT
The economics of natural resources management can be understood in terms of “virtual’’ natural resources. It is generally difficult and prohibitively expensive to transfer large quantities of water, soils, and low unit cost minerls and rocks (such as limestones) to some other places where they are required. It is, however, possible to share the benefits of water, instead of physically sharing the water. “Virtual’’ water is the amount of water needed to produce goods – for instance, 1000L (onem3) of water are needed to produce 1 kg of grain, and 13,000L of water is needed to produce 1 kg of beef. Thus, a country which exports one tonne of grain is in effect exporting 1000m3 of “virtual’’ Water. While the world’s population has doubled in the past half century, the consumption
of meat has quadrupled. About 2 kg of grain are needed to produce a weight gain of one kg of chicken. For pork, it is 3 kg, and for beef, 8 kg. For the annual production of about 200 million tonnes of meat, livestock are now fed about 40% of all grain harvested. At a given level of nutrition (say, a minimum amount of 2200 daily calories), the grain and soya bean needed to feed a pig to produce pork, will feed a man ten times the number of days, if consumed directly instead of as pork (source: National Geographic, Oct. 1958). About 70% of all water is used in food production. It is possible to convert the
per capita consumption of various items of food and other uses in terms of “virtual’’ water. The consumption of “virtual’’ water is 1400L per capita per day in Asia, and about 4000L in the case of Europe and North America. The following countries are among biggest net exporters of “virtual’’ water: USA, Canada, Thailand, Argentina, India, Vietnam, France and Brazil. The largest net importers of “virtual’’ water are Sri Lanka, Japan, South Korea, Germany, Italy, etc.
