USU Researcher says Climate Variability May Encourage Plant Diversity
Thursday, Nov. 30, 2006
USU plant ecologist Peter Adler. Photo by Melinda Smith.
Adler used handwritten data collected by researchers in Kansas from the 1930s through the 1970s. The pictured document is dated August 9, 1946.
Data used in the research study was kept in a storage shed for several decades. It was recently recovered and digitized.
Reams of weathered notes painstakingly compiled for more than 30 years on the Kansas prairie are helping researchers understand the potential impact of climate change. And the news ain’t all bad.
Utah State University plant ecologist Peter Adler and colleagues at the University of California at Santa Barbara studied meticulously handwritten data describing three common grass species that endured severe droughts, including the Dust Bowl of the 1930s, along with the wettest years on record. The research may help scientists understand the ecological effect of forecast increases in the frequency of extreme weather events due to global climate change. Their findings appeared in a recent edition of the Proceedings of the National Academy of Sciences.
Adler presents, “Persistence of Plant Species under Climate Change: Using the Past to Understand the Future,” Wednesday, Dec. 6, as the final installment of the USU College of Natural Resources’ Fall Seminar Series. Alder’s talk, free and open to all, is from 4-5 p.m. in room 102 of the Biology-Natural Resources building.
Studying the impact of climate variability on plant species diversity is a challenge, says Adler, because little long-term data is available to test scientists’ theories. But the discovery of “a remarkable data set” collected by ecologists from Fort Hays State University from the 1930s to the early 1970s enabled Adler and colleagues to observe the impact of three decades of weather events on specific plots of prairie grass and contemplate how future changes in climate variability could affect plant diversity.
Data collection on the plots stopped when the last of the ecologists retired in 1972 and the records were consigned to a storage shed. The records were recently rediscovered and digitized.
“What we found was that climate fluctuations favored different plants from year to year and prevented any one species from taking over,” says Adler, who joined the Department of Wildland Resources as an associate professor this past July.
If you think in terms of one plant species, you wouldn’t expect harsh weather events to have a positive impact on that species’ survival, he says. But if you’re looking at a diverse environment with a variety of species, you can see that each species thrives in different conditions.
Alder and colleagues developed a computer model that species’ growth rates in different years, taking into account competition from other species. “What we’re seeing is that different species are adapted to different conditions and take advantage of favorable years as they occur,” he says.
Adler’s research suggests that future increases in extreme weather events might have positive effects on diversity. But he cautions that this conclusion depends on a number of untested assumptions.
“What this research shows us is that to predict the future impact of climate change on ecosystems, we need to look beyond yearly averages and also consider climate variability,” he says.
Proceedings of the National Academy of Sciences, 22 August 2006.