How will the balance between preservation of the environment be balanced with the increasing need for mobility?

=== Owner's Research ===

"The Effects of Human Travel on the Environment" http://fubini.swarthmore.edu/~ENVS2/pfriel1/
"Travel, Human Culture, and the Environment" http://fubini.swarthmore.edu/~ENVS2/jpottag1/jpottag1essay3.htm
"The Effect of European Expansion on the Environment" http://fubini.swarthmore.edu/~ENVS2/anteneh/index.htm

=== Non-owner's Research ===