Megan Rowling Thomson Reuters Foundation 24 Aug 16;
"Human footprint" maps show people's impact on the environment has slowed
When researchers started looking at whether countries could expand their populations and economies without using up more of the Earth's limited natural resources, they expected the answer to be “no”. But their findings suggest it can be done.
A set of maps released this week show that people’s impact on the environment has been rising at a rate slower than that of economic and population growth.
While the world's population grew 23 percent and its economy 153 percent between 1993 and 2009, the global footprint of humans grew only 9 percent, calculated a team of researchers from the University of Northern British Columbia, the University of Queensland, the Wildlife Conservation Society (WCS) and six other universities.
Oscar Venter of the University of Northern British Columbia, the lead author of the study published in Nature Communications, called the results "encouraging".
"It means we are becoming more efficient in how we use natural resources," he said.
Some places even saw small decreases in environmental pressures as they got richer.
That happened in the wealthiest countries and those with strong control of corruption. They included Britain, Denmark, Belgium, Germany, the Netherlands, large parts of France, and some areas of the United States, Australia and southeast Africa.
Eric W. Sanderson, a conservation zoologist with the WCS who worked on the original "Human Footprint" study in 2002, noted the results were the same after taking into account the effects of international trade, proving those countries have managed "in some small measure to decouple economic growth from environmental impacts".
Venter said the researchers' data sent clear messages about how the world could achieve sustainable development. "Concentrate people in towns and cities so their housing and infrastructure needs are not spread across the wider landscape, and promote honest governments that are capable of managing environmental impacts," he said.
AGRICULTURAL PRESSURE
By contrast, the areas subject to the highest environmental pressures tended to be forests: the temperate broadleaf forests of Western Europe, the eastern United States and China; the tropical dry forests of India and parts of Brazil; and tracts of Southeast Asia’s tropical moist forest.
Overall, around 70 percent of the world's different ecological regions saw marked increases of over 20 percent in their human footprints. That was measured by looking at the extent of developed areas, crop land, pasture land, human population density, night-time lights, railways, roads and navigable waterways.
The researchers said one of the main drivers of growing human impact on nature is the use of less-than-prime land for agriculture.
Areas moderately suitable for farming have seen a rapid increase in human use since 1993, likely due to the expansion of agriculture and other human pressures into these more marginal lands, they added.
Globally, a worrying amount of damage has already been done both to the landscape and the wildlife it sustains.
The maps show three quarters of the planet has been significantly altered, and 97 percent of the most species-rich places on Earth have seriously changed.
"There is little wonder there is a biodiversity crisis," said James Watson who leads the WCS' climate change programme.
Maintaining biodiversity will require extensive restoration to remove and reduce existing pressures in biologically valuable regions, the study said.
Among the remaining most unspoiled lands are the Sahara, Gobi and Australian deserts, and the most remote moist tropical forests of the Amazon and Congo Basins, it said.
But while the Amazon basin is still a largely intact ecosystem, it is susceptible to accelerated deforestation and other pressures following recent policy changes in Brazil, the study warned.
The researchers' findings will inform discussion at the IUCN World Conservation Congress, which brings conservationists and world leaders together once every four years, in Hawaii from Sept. 1 to 10.
