It's an ecosystem where native plants must react to rain and temperature extremes along a dusty, winding road under an intricate, watchful plan of three Texas Agricultural Experiment Station scientists.

Thick white plastic stretches over 14-foot tall galvanized steel arches like giant, protective umbrellas to shelter 80 plots of juniper, post oak and little bluestem grass. But while the awnings prohibit nature from having her way with the young plants, the researchers may jack up the temperatures and send a rainstorm without batting an eye except to make note of the results.

"We hope to learn enough to be able to anticipate vegetation change so land managers can minimize negatives or optimize the positives of global climate change," said Dr. David Briske, Experiment Station plant ecologist.

Briske and Dr. Mark Tjoelker, Experiment Station forest ecologist, are co-investigators on this project, funded by the National Institute for Global Environmental Change. They are assisted by Dr. Astrid Volder, Experiment Station forest research associate.

What makes this global climate change study unique, Tjoelker said, is that it is in the real world -- not a computer-generated prediction model -- and it combines rainfall and warming in various amounts to measure impact on plant growth.

The researchers chose post oak, bluestem grass and junipers because those species are predominant in the 7.4 million-acre post oak savannah region from south central Texas through eastern Oklahoma. A change in rainfall and/or temperatures predicted over the next several decades could mean a shift in the dominance of these important plant species. And that could alter the way land is used and the types of wildlife able to survive there, Volder noted.

Briske and Tjoelker spent
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Contact: Kathleen Phillips
ka-phillips@tamu.edu
979-845-2872
Texas A&M University - Agricultural Communications
12-May-2004