Tropical Biodiversity at Risk
Introduction
Called the "Lungs of the earth", the tropics are rich repositories of biodiversity. The tropical rainforests are home to 60 per cent of the earth's plant species, leading many to believe that tropical plants are less susceptible to extinction. Contrary to this, a study done on plant species around the world, by Jana Vamosi and Steven Vamosi from the University of Calgary, Canada, pointed out that tropical species have a higher risk of extinction. Their findings suggest that equatorial plant species persist at naturally low population sizes, making them more susceptible, than those in other regions, to any disturbance, including human activities. For the study, human factors like GDP, population density and deforestation were taken into account. The study proved that human activity was not the direct cause behind the increasing risk of extinction. It is estimated that 20 to 45 per cent of tropical species are at risk, the researchers said.
Source
Down To Earth, January 2009