MERCED -- The theory that temperature limits how far up in the mountains trees can grow looks like it's true, but not in the way researchers had expected.
Working with Professor Lara Kueppers, UC Merced postdoctoral researcher Andrew Moyes' examination of how warmer temperatures affect alpine-area trees has been published in the international journal Oecologia.
Their work indicates some trees researchers thought wouldn't grow at the highest elevations because of the cold don't fare better when they are warmer, either.
A series of experiments in Colorado, in which seedlings were planted and then warmed under infrared radiation panels to simulate climate change, showed warmer temperatures dried the soil faster, subjecting the baby trees to more moisture stress.
"Each species has its own 'climatic comfort zone,' " Moyes said. Recent and projected climate warming should push the limber pines to grow further uphill than normal because the temperatures up higher would be warmer, too.
Moyes and collaborators found that the warmer climate can actually prompt the trees to slow or stop photosynthesizing in mid-summer, Kueppers said. Three people helped collect and analyze data, and write the paper, which focuses on the physiology of the young limber pines.
This work is just one more example of how UC Merced researchers are contributing to the world's overall understanding of climate change.
The project continues for at least one more field season, and the group and collaborators at the University of California at Berkeley, the University of Colorado and the U.S. Geological Survey are submitting proposals to expand it.
Separate paths
Graduate students Kristynn Sullivan and Chris Fradkin took distinctly different routes to UC Merced.
Sullivan left northern Virginia for the University of California's newest campus after completing a bachelor's degree in psychology at the University of Mary Washington. Fradkin built a successful career in Southern California before relocating to UC Merced.
Today, both are pursuing doctorates in the Psychological Sciences Graduate Group at the university. With 26 students and three specialty areas, the fast-growing program is one of the largest on campus. Sullivan is pursuing quantitative psychology while Fradkin is studying health psychology.
Jan Wallander, professor of psychological sciences and chair of the graduate group, said the high-level program prepares students to become independent researchers and scientists. Students are matched with faculty mentors and often work with each other.
Both Sullivan and Fradkin say they appreciate the faculty, research opportunities and atmosphere at UC Merced.
"I really liked the idea of coming to a small school that was in its growth state," said Sullivan. "The individualized attention has been great."
Sullivan considered universities across the country before choosing UC Merced. She liked the faculty and program -- and the stark contrast between a new, cutting-edge campus and the more than 100-year-old university she attended in Virginia.
Quantitative psychology deals with finding the best research methodology or statistics to apply to a question or issue.
Fradkin's research centers on obesity risk in early adolescents and the factors -- such as race and socioeconomic status -- that might influence that risk.
Some findings may challenge the presumption that children in better-educated and higher-income families are at lower risk for obesity. The notion of the "social gradient" as applied to weight applies to some racial-ethnic groups, but not to all, Fradkin said.
UC Merced Connect is a collection of news items written by the University Communications staff. To contact them, email communications@ucmerced.edu.