University of Vermont

University Communications


Leading Ecologists, Computer Modelers Seek Global Answers

By Joshua Brown Article published October 11, 2006

“The bats go out every night and eat moths that lay eggs in a cotton bole and destroy it,” says Cutler Cleveland, pointing to a PowerPoint chart that shows arrows flowing from boxes with labels like “natural predators” and “pesticides.”

“The bats are good for the [cotton] farmers,” he says, but some people use dynamite to blow up the bats’ caves “so they can back up a semi and collect the guano for garden fertilizer.”

With fewer bats, the farmers are forced to buy and use more pesticides.

Cleveland, director of the Center for Energy and Environmental Studies in Boston, is one of several dozen U.S. and international scientists gathered on the fifth floor of UVM’s Waterman Building from October 9-13 to figure out how information like this might be included in a new computer model.

They’d like to show how natural pest controls, like bats, and other free “ecosystem services” of nature — like clean water from wetlands instead of treatment plants — have huge economic value for people.

With insights and data from numerous experts — including Cleveland’s information on bat caves and agricultural systems in Mexico and Texas — the scientists are starting on a year-long effort to build models and maps that will represent the ecosystem services of the whole world.

“What’s going to have the greatest benefit for a community in the long run, a wetland or a Walmart?” asks Robert Costanza, director of UVM’s Gund Institute for Ecological Economics, who organized the five-day meeting. It's the first major step in an $813,000 project titled “Dynamic Modeling of Ecosystem Services to Promote Conservation,” funded by the Gordon and Betty Moore Foundation.

“If the wetland is seen having no value — or an incalculable value — decision makers are not equipped to make a good decision,” he says.

These scientists believe that a first step to understanding the value of benefits freely provided by nature is to put a price tag on them. Following Costanza’s widely read 1997 article in the journal Nature that estimated the planet’s ecosystem value at $33 trillion per year, researchers have spent the last decade developing a quantified understanding of how animals and soils and forests and the atmosphere underpin the human economy.

The next step is to create easy-to-use maps for policy makers that connect this economic and ecological data to their particular landscapes. Seated in a semi-circle around the Grace Coolidge room (while her portrait looks on) the scientists Costanza has invited —from some two dozen universities, conservation organizations and government agencies — type on laptop computers as Cleveland talks. Once their project is complete in a year or so, land managers will be able visit an interactive website that allows them to consider various futures by projecting the impacts from imaginary land use decisions.

“We’re working at many scales from local cases, to regions, to the global,” says Rolf Seppelt, a mathematician and landscape ecologist from the Center for Environmental Research in Leipzig, Germany, who came to Burlington for the meetings.

“We know a lot now about global change and ecosystem services, and the Millennium Ecosystem Assessment does a very good job of helping us understand what could happen in various scenarios,” he says. “But this meeting aims to take the next step and go beyond scenarios to ask what is realistic, what aspects of human behavior and policy can we really change?”

The project will continue in the spring with another gathering of the scientists on campus. “The hope is that the models we’re starting now will evolve and be calibrated by observations of the real world," says Kenneth Mulder, from the Kellogg Biological Station at Michigan State University and who recently completed his Ph.D. at UVM. “At the end of the year if we have a functional global model of ecosystem services, we’ll have come a long way.”

“Eventually we’d like to have something that’s a bit like (the urban simulation program) SimCity or Google Earth,” he says.