Imperiled Riches—Threatened Rainforests

URBANIZATION

Urban and residential area expansion cause significant forest loss, both in the consumption of building materials and as a source of land. While urbanization can reduce direct pressures on forests by the migration of rural residents to population centers, urban and suburban sprawl can be damaging when they occur in frontier settlements and boomtowns. A single gold or gem find can quickly swell a population of a remote forest outpost as a sea of prospectors rush to the area in hopes of finding riches.

Centrally planned urban experiments has resulted in tremendous forest loss in parts of the world. Indonesia's massive transmigration program moved some 730,000 families—more than six million people—to the outer islands of New Guinea, Borneo, Sumatra, and Sulawesi in an effort to reduce population pressures on the crowded central islands of Java and Bali. The program was generally seen as a failure since many colonists failed to establish successful farms in the hinterlands while large areas of primary forest were cleared. Today some of the worst fires in Indonesia occurs on these once-forested lands. Conflicts between migrants and original inhabitants remains a problem, especially in places like Indonesian New Guinea.

Rural abandonment can also spur outright conversion of forest by industrial farmers and ranchers, especially in areas suitable for large-scale agriculture. For example, research published in 2007 found that in area where small farmers in Bolivia and Panama have moved to cities, their holdings have not reverted to forest but instead been converted to larger, more intensive agricultural use. Meanwhile in Sumatra and Indonesian Borneo, agroforests once managed by local communities have been widely cleared by palm oil developers and pulp and paper companies.

Review questions

• Why are tigers endangered?
• How can alien or invasive species impact the environment?