comprehensive understanding that his true "wealth" is, and always was, in his sustainable relationship with all life systems of the planet- Nothing more, Nothing less. For the sole purpose of insatiable profit, That "understanding" has been completely bred out of him never to return within this block of earth's history. Have a nice day Kelsey, Kansas "" I believe this study and poll is a good idea. The world needs to change something annually. We should choose one of these and make it happen one year then choose another and keep doing it. If we do not, nothing in the world will be fixed and the world will continually be harmed and it will eventually come to an end. I believe we should stop global warming by using the carbons that are being put into the air for something else. Robert M. Peart, Univ of Florida "" Excellent choices - should be publicized because of the lack of appreciation of what engineering can do for these problems. The carbon sequestration and nitrogen management challenges have some interrelationships that should be realized. Simple example: Better fertilization of trees for lumber can result in faster growth, thus a higher rate of carbon sequestration within the wood itself (via photosynthesis). If this wood is used for construction, the carbon that it contains is taken out of the atmosphere for many years. Development and standardization of small nuclear power plants that can shown to be safe and reduce carbon dioxide in the atmosphere. Perry