Ways to safeguard essential supplies: ecosystem investment through waste reduction and conservation is the best possible insurance policy says the US's Worldwatch Institute. This year's news bulletins have certainly shown the value of 'Nature's Factories'.(Water)

BY TAKING ADVANTAGE of the work that healthy watersheds and freshwater ecosystems perform naturally, cities and rural areas can purify drinking water, alleviate hunger, mitigate flood damage, and meet other societal goals at a fraction of the cost of conventional technological alternatives, according to a new Worldwatch study by Sandra Postel, director of the Global Water Policy Project and a Worldwatch Institute senior fellow.

But because commercial markets rarely put a price on these 'ecosystem services', and because governments around the world are falling to protect them, they are being lost at a rapid rate, writes Postel in her report, Liquid assets: The critical need to safeguard freshwater ecosystems. Global warming is the wild card that could further exacerbate the …