09/29/2008

Climatic Change is Causing Rapid Shifts in Plant Distribution in California Mountains

Summary

Ongoing global warming is expected to shift the geographic distribution of plants as species expand into newly favorable areas and decline in increasingly hostile locations.  University of California scientists sponsored by the DOE Program for Ecosystem Research compared surveys of plant locations made in 1977 and 2006-2007 along a 2,314-meter elevational gradient in Southern California’s Santa Rosa Mountains.  During the 30 years between the surveys the local climate warmed, precipitation variability increased, and the amount of snow decreased.  As reported recently in the Proceedings of the National Academy of Science the scientists found that the average elevation of the dominant plant species rose in elevation by about 65 meters during the 30 years between the two surveys.  That upslope change in plant distribution could not be attributed to changes in air pollution or fire frequency and appears to be a consequence of changes in regional climate.

References

Kelly, A.E. and M.L. Goulden. 2008. Rapid shifts in plant distribution with recent climate change. PNAS 105:11823-11826.