Vegetation Shifting Around the World

By June 9, 2010 February 21st, 2013 Impacts

From Berkeley press release: Vegetation around the world is on the move, and climate change is the culprit, according to a new analysis of global vegetation shifts led by a University of California, Berkeley, ecologist in collaboration with researchers from the U.S. Department of Agriculture Forest Service. Researchers present(ed) evidence that over the past century, vegetation has been gradually moving toward the poles and up mountain slopes, where temperatures are cooler, as well as toward the equator, where rainfall is greater. The results came from an analysis of hundreds of field studies of observed 20th century climate. The analysis identified field studies that examined long-term vegetation shifts in which climate, rather than impacts from local human activity such as deforestation, was the dominant influence.

The researchers found 15 cases of biome shifts since the 18th century that are attributable to changes in temperature and precipitation. "This is the first global view of observed biome shifts due to climate change," said the study’s lead author Patrick Gonzalez, a visiting scholar at the Center for Forestry at UC Berkeley’s College of Natural Resources. "It’s not just a case of one or two plant species moving to another area. To change the biome of an ecosystem, a whole suite of plants must change." The researchers calculated that from 1901 to 2002, mean temperatures significantly increased on 76 percent of global land, with the greatest warming in boreal, or subarctic, regions.

Some examples of biome shifts that occurred include woodlands giving way to grasslands in the African Sahel, and shrublands encroaching onto tundra in the Arctic. "The dieback of trees and shrubs in the Sahel leaves less wood for houses and cooking, while the contraction of Arctic tundra reduces habitat for caribou and other wildlife," said Gonzalez, a lead author on reports of the Intergovernmental Panel on Climate Change (IPCC). "Globally, vegetation shifts are disrupting ecosystems, reducing habitat for endangered species, and altering the forests that supply water and other services to many people." … "Scientists had not quantified this risk before," said Gonzalez. "We developed a simple classification system that natural resource management agencies can use to identify regions in greatest need of attention and planning. We have worked with the U.S.D.A. Forest Service and the U.S. Fish and Wildlife Service to explore the application of our results to adaptation of natural resource management." Gonzalez said that because of limited resources, it may be prudent to focus on protecting areas of greater resilience to ecological changes so that they can serve as refuges for plants and animals. "It is also useful to identify places of higher vulnerability, because agencies will need to consider adaptation measures for vulnerable ecosystems," he said. "Some shifts in vegetation could increase fuel for wildfires, for example, so prescribed burning may be necessary to reduce the risk of catastrophic fires." "Approximately one billion people now live in areas that are highly to very highly vulnerable to future vegetation shifts," said Gonzalez. "Ecosystems provide important services to people, so we must reduce the emissions that cause climate change, then adapt to major changes that might occur."

SKAGGS ISLAND, CA (KGO) — As the gulf leak wears on and on, it has almost upstaged another environmental issue: climate change which it wears on. Local reports in the past two days paint very sobering pictures. For Stephanie Sanchez of Petaluma, this was as good a day as any for capturing a moment in time at Skaggs Island, which is part of an environment influx. "I’m most aware of how every moment changes," she said. That prophetic comment from an artist came on a day when scientists said pretty much the same thing, with data to back it up. "We can expect changes more in accordance with a tropical environment," report author Dr. Bill Sydeman said. Sydeman helped author a report by the National Oceanic and Atmospheric Administration. It looks at the Gulf of the Farallones and concludes that the effects of climate change are well underway in that region. In some places, water temperatures have risen five degrees Fahrenheit in 30 years, causing warm water species to move in, and colder ones to move out. "It’s mixed. There are winners and losers. If you’re a salmon, you’re losing in this battle," Sydeman said. It is another example of the difference between weather, which is short term and climate, which changes over decades. And now we can see that climate is affecting changes inland as well. "If we continue to emit greenhouse gasses, half the state is vulnerable to shifts in the future," Dr. Patrick Gonzales from UC Berkeley said. Gonzales expects that with less rain in Southern California, we can expect more brush and forest fires. More worrisome is that pine trees may disappear from parts of the Sierra. They play a crucial role in retaining water for the spring run-off, which fills rivers, lakes, reservoirs and comes through your tap. "Well it’s the trees on land that soak up water and feed reservoirs. Some of these shifts are reducing trees on the land. They’re dying out," Gonzales said. According to scientists, change is normal and constant, but change this fast is more than a little frightening.

Gonzales, et. al., Global patterns in the vulnerability of ecosystems to vegetation shifts due to climate change, Global Ecology and Biogeography, June 2010.