Pavan Sukhdev: Put a value on nature!

Every day, we use materials from the earth without thinking, for free. But what if we had to pay for their true value: would it make us more careful about what we use and what we waste? Think of Pavan Sukhdev as nature's banker -- assessing the value of the Earth's assets. Eye-opening charts will make you think differently about the cost of air, water, trees ...