OPINION/COMMENTARY

FEEDING PEOPLE WHILE PRESERVING HABITATS

Global food demand is expected to more than double by 2050, and scientists are trying to find a balance between farming and species conservation, especially in developing countries, according to Science magazine.

According to Birdlife International’s World Bird database:

* Farming is the biggest threat to 37 percent of bird species listed as “threatened” and 57 percent of those listed as “near-threatened” in the developing world.
* The impact of farming to bird species in developed countries is smaller, affecting only 24 percent of “threatened” birds and 33 percent of “near-threatened” birds.
* Furthermore, while farming is becoming more efficient, (global food production outpaced population growth between 1961 and 1999), crop yields in developing countries still lag behind developed countries by about 20 years.

Scientists are examining two possible solutions: high-yield farming on less land, or wildlife-friendly farming, where more patches of habitat are retained on farmland, resulting in more species diversity but lower crop yields.

Rhys E. Green of the University of Cambridge and his coauthors found:

* In modeling each scenario, the same crop yield density could be achieved by practicing high-yield farming on 20 percent of a plot of land, or low-yield farming on the entire plot of land.
* However, the extent to which species preservation is greater on low-yield farmland is questionable.

Previous studies on Latin American countries suggest that higher yield increases have lower rates of deforestation, which assists in species preservation.

Scientists have not concluded which method would be more effective, or perhaps whether a combination of both methods would strike a balance, but the issue of farming versus species conservation is key research area as food demand increases.

Source: R.E. Green, et al., “Farming and the Fate of Wild Nature,” Science, January 28, 2005.

For abstract (registration required):

http://www.sciencemag.org/cgi/content/abstract/307/5709/550