The ultimate driving force behind all deforestation is human overpopulation; both the population in the temperate region that places demands on the resources derived from the tropical rainforests, and the expanding population of developing tropical nations, who exploit the rainforest for survival. As of 2012, the world's population exceeds 7.2 billion people. Each minute another 148 people were added to the planet, each day another 214,000, and each year another 78,000,000 (2011 data). Despite declining global birth rates, which have now fallen to the lowest level in recorded history, the U.S. Bureau of the Census projects the population will reach 8 billion by 2026 and expects the population to then level off at 9-10 billion in 2050, barring an outbreak of a widespread deadly plague or a catastrophic environmental disaster. Over 99 percent of this new growth will occur in the less-developed countries of today.
Whether one subscribes to the Malthusian view or not, this increase in human population will place tremendous pressure on the planet's resources. The most pressure will come from the world's developing countries, which have the fastest-growing populations and most rapid industrial growth. The rapid economic transformation of India and China will present one of the greatest challenges to managing future resource consumption and environmental sustainability.
Despite economic growth in developing countries, they continue to be challenged by poverty and hunger. One in seven people in the world lacks sufficient food to fulfill basic daily requirements, despite increasing food supplies worldwide. There are many reasons for this hunger, including the increasing cost of food against falling real wages and the limited access to food reserves. To meet projected food demand, the FAO estimated in 2005 that another 222 million acres (90 million hectares) of new land must be brought into agriculture in developing countries, mainly in sub-Saharan Africa and Latin America. The good news is there are 800 million to 1.6 billion hectares of degraded land worldwide that could be suitable for agricultural production. Cultivating these lands could reduce pressure on critical ecosystems including rainforests, peat swamps, and high-biodiversity savannas.
Additionally, as developing countries become more integrated into the world economy, they will place greater demands on their own natural resources and as a result, pollution and environmental degradation in recent decades have been growing at a rate exceeding the population growth rate. For example, during the 1980s, the population of tropical developing countries grew by roughly 19 percent, while their deforestation expanded by 90 percent. Industrial demand increases for wood, oil, and mineral products found on forest lands.
One of the greatest threats to the world's environment is the compounding numbers of rural poor who turn increasingly to the rainforests to feed and shelter themselves. These poor farmers are sometimes pushed off more fertile soils by large, wealthy landowners who are capable of purchasing land or using political influence to gain title to land. Without realizing it, these poor farmers are perpetuating their own situation by their role in deforestation, which worsens their quality of life by increasing their chance of disease, degrading their drinking water stocks, escalating soil erosion, and leaving their children without the benefits of sustainably utilized forest. As the human population grows, the quality of all forms of life plummets as people are forced to move into more and more marginal lands with higher incidence of natural disasters (floods), crop failures, and disease.
Children in New Guinea. (Photo by R. Butler)
Review questions:
How does population growth impact the environment?
How can a falling population growth rate in developed countries still result in deforestation and other environmental problems?
Current population information comes from the U.S. Bureau of the Census, Report WP/98, World Population Profile: 1998, U.S. Government Printing Office, Washington, DC, 1999.
FAO makes predictions on future food-land requirements in State of the World's Forests 1997 (SOFO).
Myers calculates that the population of tropical developing countries grew by roughly 19%, while their deforestation expanded by 90% during the 1980s in Myers, N., "Population and Biodiversity," Ambio Vol. 24 No. 1, Feb. 1995.