In his discussion here about how to make globalization work, Nobel laureate Joseph Stiglitz talked about the importance of assets like a clean environment. Because the environment isn't mobile, like money or factories, protecting it can help shore up a region's competitive strength and attract workers who value it. I remembered the story of a high-powered U.S. executive who kept getting sick on the polluted air in Shanghai and finally packed it in.

What if the value of nature could be quantified like any other asset? The Nature Conservancy, World Wildlife Fund and Stanford University are teaming up on a new project to calculate nature's economic benefits, looking at clean water and air, soil fertility and other factors.

Natural systems should be protected for their economic value, they contend. One study along those lines found that the economic benefits of conserving forests in Paraguay exceeded the benefits of farming the same land, for example.

The Natural Capital Project starts in three pilot areas -- the Eastern Arc Mountains of Tanzania, the upper Yangtze River Basin in China and the Sierra Nevada region in California. It aims to measure the economic value of "ecosystem services" and incorporate the data into policy decisions.