Putting People in the Map: Ecologists Remap Biosphere to Include Humans

Mon, 26 Nov 2007 12:00:00 -0500
ovpr-news-2007

Photo Caption: Ecologist Erle Ellis has helped design a new way of mapping the Earth to include human impact.

Editor’s Note: Since its publication, Ellis and Ramankutty’s research has received international media attention, including coverage in Science and a video feature on Discover.com.

Other coverage included: Wired magazine’s “Wired Science” blog, United Press International, Der Spiegel, Earth & Sky, Earthtimes UK, DailyIndia.com, Science Daily, Digg.com, Propellor.com, the Agricultural Biodiversity Blog, www.terradaily.com and others.

Pristine wilderness is a thing of the past and it’s time to adjust our vision of the biosphere accordingly, say a team of American and Canadian eco-geographers in newly published research.

Erle Ellis, associate professor of Geography and Environmental Systems at UMBC, and Navin Ramankutty, assistant professor in McGill University’s Department of Geography and Earth System Science Program, used global data from satellites and land management statistics to map a new system of “anthropogenic biomes” or human biomes, that describe the biosphere as it exists today, the result of human shepherding and reshaping of ecosystems. Their map provides a 21st century challenge to the classic images of Earth's wild ecosystems that appear in nearly every ecology and earth science textbook.

Their research was published in the Nov. 26 issue of the journal Frontiers in Ecology and the Environment together with maps viewable in Google Earth and Google Maps at the Encyclopedia of Earth (a sort of Wikipedia for earth scientists and ecologists) and a printable classroom wall map for use by ecologists, educators and the public.

“The fact that an area is now covered by forests depends more on human decisions than it does on climate” said Ellis, who has studied anthropogenic landscapes in the field across rural China since 1992. He was inspired to investigate human landscapes globally during a research sabbatical at the Department of Global Ecology of the Carnegie Institute of Washington at Stanford University.

Photo Caption: Ellis has studied human biomes in rural China since 1992.

“The classic biomes, such as tropical rainforests or grasslands, were based on differences in vegetation caused by on climate,” said Ellis. “Now that humans have fundamentally altered global patterns of ecosystems and biodiversity, these biomes are rarely present across large areas any more. It is time for our map of the biosphere to reflect this new reality- that nature is now embedded within human systems” said Ellis.

Another key message from Ellis and Ramankutty was that ecologists should turn their focus to the changing ecosystems right underneath their feet. “A section of our paper is entitled ‘ecologists go home,’” said Ramankutty, an expert on global agriculture’s connection to environmental change. “Ecologists go to remote parts of the planet to study pristine ecosystems, but no one studies it in their back yard,” he said.

“We can no longer study ecology while ignoring humans,” Ellis said. “Humans are now as much a part of nature as the weather and human and ecological systems are so intricately linked that focusing just on nature gets in the way of conserving nature for future generations. We need to sustain positive interactions between human systems and ecosystems, not avoid these interactions. Focusing on so-called wilderness areas ignores more than four-fifths of Earth’s ice-free land. Ecologists need to do more research in places where humans live,” said Ellis.

Other key findings of the research:

More than three-quarters of our ice-free land surface is human altered. Wildlands cover just 22 percent of ice-free land today, and most of this land is barren and relatively unproductive.

Rangelands are the largest anthropogenic biomes, followed by cropland and forested biomes.

More than 80 percent of people live in dense settlements and village biomes, though these cover just seven percent of the Earth’s ice-free land surface. Village biomes are about five times as extensive as urban biomes and are home to about a quarter of Earth’s human population.

Anthropogenic biomes are mosaics. Instead of distinct vegetation or land-use types, anthropogenic biomes are complex mixtures of different land uses (settlements, crops, pastures, forests) that are classified by degree and type of human influence. For example, village biomes, which are found mostly in Asia and Africa, are crowded networks of towns and rural settlements embedded in intensively managed croplands and rice paddies alongside patches of less disturbed vegetation in hilly areas.

UMBC’s national reputation for excellence in earth and environmental science is growing. According to Thomson Scientific's Science Watch, UMBC's geoscience research ranked third nationally in citation impact for 2001-2005. The only other U.S. universities producing more frequently cited geoscience research papers were Harvard University and the Georgia Institute of Technology.

UMBC ranks third nationally in NASA research funding and is home to two major collaborative NASA earth science research centers and the U.S. Geological Survey’s Maryland/Delaware/D.C. Water Science Center.