WATERS OF STRIFE

摘要

The concept of fresh water as a free good is fast becoming an economic and political anachronism. An old Inca proverb says: "The frog does not drink up the pond in which it lives." This simple wisdom captures well one of the urgent challenges of our time-reconciling growing human claims on the earth's water bodies with the need to protect water's fundamental ecological functions. As world population heads toward six billion and demands for food and material goods rise apace, it is a challenge we cancontinue to ignore only at our own peril. In theory, the planet has ample fresh water to support the world's people, but much of it is not available when and where needed. At least 20 per cent of the renewable water supply-that generated each year by thesolarpowered hydiological cycleis too remote from population centres to be of use. A large portion of the remainder runs off in floods, and therefore cannot be supplied reliably to farms, industries and households. After accounting for this tunequal distribution of fresh water in time and space, the picture of plenty is quickly revealed to be an illusion.