The International Tundra Experiment is a coordinated network of experiments focusing on the impact of climate change on select plant
species, community composition, and ecosystem processes in tundra and alpine vegetation. ITEX uses a common warming method to examine how
the tundra biome may respond to climate change. The program began in 1990. Today, there are more than two dozen circumpolar and alpine
sites that participate in the ITEX program.
The Tibetan Plateau ITEX site was established in 1997, when Klein set up an experimental warming x grazing study at the Haibei Research
Station on the northeastern region of the Tibetan Plateau in Qinghai Province. Klein established this project in collaboration with
Dr. Zhao Xinquan, the Director of the Northwest Plateau Institute of Biology, Chinese Academy of Sciences. With funding from the U.S.
National Science Foundation, Klein and colleagues have examined the independent and combined effects of warming and grazing on plant community composition,
species diversity, productivity, carbon and nitrogen cycling, and key ecosystem services. Results from the first five years of this
experiment have been published in Ecology Letters, Global Change Biology, Ecological Applications and Ecosystems.
ITEX-wide results are reported in the Proceedings of the National Academy of Sciences and Ecology Letters. As part of the
International Polar Year, the National Science Foundation is currently supporting analyses of the longer-term (>10 years) responses
to experimental warming and changes in control plots over time at the Tibetan Plateau site, the Colorado Niwot Ridge site and across
the rest of the ITEX network.