Despite widespread gloom and doom about global warming, a Utah State University researcher says climate fluctuations may be good for some plant species.

Peter B. Adler and his colleagues believe it may be advantageous for native grasses to undergo changes in climate.

The research used data recorded in Kansas from the 1930s through the early 1970s. The data, which was kept in a storage shed for several decades, has recently been recovered and digitized. Although the study, "Climate variability has a stabilizing effect on coexistence of prairie grass," looks at events in the past, the period studied saw major rainfall fluctuations, and the results might point to what might be expected in a time of global warming.

Adler, who started at USU in July as an assistant professor, carried out most of the study's work at the University of California at Santa Barbara. His four co-authors — Janneke HilleRisLambers, Phaedon C. Kyriakidis, Qingfeng Guan and Jonathan M. Levine — are from Santa Barbara. The study was published in Proceedings of the National Academy of Sciences.

Ecologists at Fort Hays State University at Hays, Kan., studied rangeland conditions every year in one-meter-square plots in the Kansas prairie. They kept track of individual plants, studying the plots for 34 years, until 1972.

The plots are "still marked, but 1972 is when one of the key players retired, so they stopped doing the censuses," Adler said.

Three common grass species, growing near each other, were tracked.

One of the study's findings is that, in the words of the report, "temporal variability increases low-density growth rates, buffering these species against competitive exclusion."

"It's a little bit surprising," Adler said. "If you think about just one species, you wouldn't intuitively expect that to be true."

If a farmer is growing a single type of plant, one would suspect that he'd "want good conditions every year. Why would you want bad years?"

But in the wild, with several species growing nearby, the scientists found that climate variability may prevent a single species from taking over.

"Basically, one species may be favored one year, another species the next year." The diversity of the prairie benefits from the climate variation.

Does that mean plants may do better if climate change comes because of global warming?

"We don't want to make any predictions," Adler said. "But we think the important message is, if you want to predict the future, that you need to consider variability."

And from what the past shows, variability is not necessary a bad thing.

"It's potentially good news," Adler added. In times of climate change, the effect "might allow these plants to stick around a little bit longer."

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