Not being a scientist, I might be missing something here, but it seems to me that large cities must be far more environmentally sound than rural communities. There is the the obvious environmental benefit that subways and buses have over private cars, and the close proximity of residential and commercial areas makes many tasks that would require a substantial amount of driving in the country to be done on foot. In addition, tall apartment buildings allow thousands of people to live on an area of land that might house a couple of families in the country. A far more efficient usage. It would be ironic if people's need to be in touch with nature is contributing to its destruction.