According to a new report 75% of the earth’s land surface area is under pressure from buildings, roads, crops and other human activity.

As it stands the pressures of the human footprint are being felt most keenly in those areas of high biodiversity, which tend to be the most wild. However researchers claim that the human population footprint is now growing more slowly than population and the economy, writes Kevin Krajick for Phys.org. The full report was published in the journal Nature Communications this week.

Human Footprint, Earth
Photo by Kevin M. Gill

Average footprint rising slower than thought

Over the period 1993-2009 population grew 23%, while the economy grew 153%. However human influence on land increased by just 9%. The data suggests that urbanization and more sustainable use of resources could be helping, even as resource consumption reaches levels never before seen.

“The fact that the average footprint is not rising nearly as fast as our economy or population is good news,” said study coauthor Marc Levy, a political scientist at Columbia University’s Center for International Earth Science Information Network (CIESIN). “It gives us some basis to hope we can save some of the natural areas we have left.”

This latest report follows on from a 2002 study that is responsible for the term “human footprint.” The study used data from the early 1990s to show how the reach of modern civilization had expanded.

New areas coming under pressure

Those large population centers in mid-latitudes were shown butting up against the Amazon, the Arctic and other remote regions. The study showed that a whopping 98% of the land on which rice, wheat or maize could be cultivated was under human influence.

The new report shows that the same trends have continued, but the developments have not been nearly as fast as predicted. The report was produced by a team of researchers led by Oscar Venter of the University of British Columbia and Eric Sanderson of the Wildlife Conservation Society.

The scientists used the latest computing and satellite imagery technology to have another look at human influence on the land. The eight factors under consideration were: extent of built environments; crop land; pasture; population density; night-time lights; railways; roads; and navigable waterways.

As expected, western Europe, the eastern United States, China, India, and parts of Brazil and southeast Asia were among the areas under the highest pressure. In contrast those areas that are not used by humans are largely hostile, including the northern tundra and boreal forests; the Sahara, Gobi and Australian deserts; and the wet forests of the Amazon and Congo basins.

More work needed to ensure sustainability

Even these hostile areas are being pressurized, with 23 million square kilometers of almost uninhabitable land subject to new incursions during the study period. In contrast there were some places that saw decreasing pressure, but all of them are situated in wealthy countries with functional governments.

Nearly every single nation in western and northern Europe saw declining footprints following massive efforts to introduce sustainable energy production and other activities.

According to Levy some of the findings can be attributed to urbanization in South America and other regions, where small farmers and other sections of the population are moving away from their lands to the cities. As a result some decreased pressure has been noted alongside slower than expected increases.

However it is important to note that population and resource consumption continue grow. Levy says that “business as usual is not going to get us there” if the aim is sustainability in the long term. Rather than allowing trends to “happen by accident, maybe there are ways we can leverage them,” said Levy. “There’s a new interest in finding ways of encouraging things like this to happen.”