Human population altered 97% of world''s species-rich areas

Sydney

Researchers have found that the presence of humans have seriously altered 97 per cent of world's most biologically species-rich areas such as tropical rainforests.

"The most species-rich parts of the planet — especially including the tropical rainforests — have been hit hardest," said Bill Laurance, Professor at James Cook University in Queensland, Australia.

A study showed that the environmental pressures were widespread, with only very few remote areas escaping the damage.

"Humans are the most voracious consumers Earth has ever seen. With our land-use, hunting and other exploitative activities, we are now directly impacting three-quarters of the Earth's land surface," Laurance said.

Seventy-one per cent of global ecological regions saw a marked increase in their human populations.

Conversely, wealthy nations and those with strong control of corruption showed some signs of improvement.

"In broad terms, industrial nations and those with lower corruption appear to be doing a better job of slowing the expansion of their human footprint than poorer countries with weak governance," Laurance added.

However, the wealthy countries have a much higher per-capita footprint. So each person was consuming a lot more than those in poorer nations, he stated.

The suitability of lands for agriculture appeared to be a major determinant where ecological pressures appeared across the world.

For the study, the team combined data garnered from unprecedented advances in remote sensing with information collected via surveys on the ground.

They compared data from the first survey in 1993 to the last available information set from 2009.

"While the global human footprint expanded by 9 per cent from 1993 to 2009, it didn't increase as fast as the human population that rose by a quarter or economic growth which exploded by over 150 per cent during the same period," Laurance noted.

"The bottom line is that we need to slow rampant population growth, especially in Africa and parts of Asia, and demand that people in wealthy nations consume less," Laurance suggested.

The findings were published in the journals Nature Communications and Nature Scientific Data. — IANS