As resources become scarce, they become more valuable. Value is evidenced both by the increasing prices of resources and by controversy over resource allocation and management. From forest harvesting and land use conversion throughout North America, to the fragmentation of tropical bird habitat, to acid rain deposition in Eastern Europe, to Siberian tiger habitat loss in Russia, people have significantly affected the ecosystems of the world. Expanding population pressures continue to cause the price of resources to increase and to intensify conflicts over resource allocation
