Climate change could severely impact California's unique native plants, a new study has indicted, adding that these plants could suffer more than an 80 percent reduction in geographic range by the end of this century.
Researchers at the University of California, Berkeley, carried out the study.
Because endemic species - native species not found outside the state - make up nearly half of all California's native plants, a changing climate will have a major impact on the state's unparalleled plant diversity, the researchers have warned.
"Our study projects that climate change will profoundly impact the future of the native flora in California," said David Ackerly, UC Berkeley professor of integrative biology.
The magnitude and speed of climate change today is greater than during past glacial periods, and plants are in danger of getting killed off before they can adjust their distributions to keep pace," he added.
The researchers have projected that, in response to rising temperatures and altered rainfall, many plants could move northward and toward the coast, following the shifts in their preferred climate, while others, primarily in the southern part of the state and in Baja California, may move up mountains into cool but highly vulnerable refugia.
According to first author Scott Loarie, from Duke University's Nicholas School for the Environment, who has worked with Ackerly on the analysis for the past four years, "In nearly every scenario we explored, biodiversity suffers - especially if the flora can't disperse fast enough to keep pace with climate change."
The authors identified several "climate-change refugia" scattered around the state.
These are places where large numbers of the plants hit the hardest by climate change are projected to relocate and hang on.
Many of these refugia are in the foothills of coastal mountains such as the Santa Lucia Mountains along California's Central Coast, the Transverse Ranges separating the Central Valley from Los Angeles and the San Gabriel Mountains east of Los Angeles.
Many of these areas are already under increasing pressure from encroaching suburban development.
"There's a real potential for sheltering a large portion of the flora in these refugia if they are kept wild and if plants can reach them in time," said Loarie.
"Part of me can't believe that California's flora will collapse over a period of 100 years," said Ackerly.
"It's hard to comprehend the potential impacts of climate change. We haven't seen such drastic changes in the last 200 years of human history, since we have been cataloguing species," he added.