The greatest damaging impacts of human activities on protected land is found in heavily populated places including Asia, Europe and Africa, said the study published in the journal Science.
"We found major road infrastructure such as highways, industrial agriculture, and even entire cities occurring inside the boundaries of places supposed to be set aside for nature conservation," said Kendall Jones from the University of Queensland in Australia.
"More than 90 per cent of protected areas, such as national parks and nature reserves, showed some signs of damaging human activities," Jones added.
For the study, the researchers used the most comprehensive global map of human pressure on the environment, the Human Footprint, to analyse human activity across almost 50,000 protected areas.
The results showed that six million square kilometres of protected land -- equivalent to two-thirds the size of China -- is in a state unlikely to conserve endangered biodiversity.
Large, strictly protected areas were under far less human pressure than smaller protected areas where wider ranges of human activities were permitted, the findings showed.
The study clearly showed nations were overestimating the space available for nature inside protected areas, said James Watson, Professor at the University of Queensland.
"Governments are claiming these places are protected for the sake of nature when in reality they aren't," Watson said.
"It is a major reason why biodiversity is still in catastrophic decline, despite more and more land being protected over the past few decades," Watson added.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
