Navigation Links
History of fire and drought shapes the ecology of California, past and future
Date:8/6/2014

Fire season has arrived in California with vengeance in this third year of extended drought for the state. A series of large fires east of Redding and Fresno, in Yosemite, and on the Oregon border prompted Gov. Jerry Brown to declare a state of emergency on Sunday, August 3rd.

As force of destruction and renewal, fire has a long and intimate history with the ecology of California. Ecological scientists will discuss aspects of that history in detail at the upcoming 99th Annual Meeting of the Ecological Society of America on August 10 15th, 2014.

"Big fires today are not outside the range of historical variation in size," said Jon Keeley, an ecologist based in Three Rivers, Cal., with the U.S. Geological Survey's Western Ecological Research Center, and a Fellow of the Ecological Society.

Keeley will present research on the "association of megafires and extreme droughts in California" at the Annual Meeting as part of a symposium on understanding and adapting to extreme weather and climate events.

He will synthesize his research on the history of wildfire across the entire state, contrasting historical versus contemporary and forested versus non-forested patterns of wildfire incidence. He and his colleagues reviewed Forest Service records dating to 1910, as well as a wealth of newspaper clippings, compiled by a Works Progress Administration archival project, that stretch back to the middle of the last century.

Understanding historical fire trends, Keeley said, means recognizing that when we talk about wildfire in California we are talking about two very different fire regimes in two different ecosystems: the mountain forests and the lower elevation chaparral, oak woodlands, and grasslands.

The chaparral shrublands of southern California, and similar sagebrush ecosystems in the Great Basin, are not adapted to the kind of frequent fire typical of the mountain conifer forests in California. Fires in the lower elevation ecosystems are always crown fires, which kill most of the vegetation. In the millennia before humans arrived, these ecosystems burned at intervals of 100 to 130 years.

These lower elevation ecosystems experienced unprecedented fire frequency in the last century, with fire returning to the same area every 10 to 20 years, altering the ecology of the landscape.

"In Southern California, lower elevation ecosystems have burned more frequently than ever before. I think it's partly climate, but also people starting fires during bad conditions," Keeley said. Bad conditions include extended droughts and dry fall days when the Santa Ana winds blow through the canyons.

In high elevation conifer forests, spring temperatures and drought are strongly correlated with fire, and Keeley thinks climate change and management choices are likely playing a role in current trends. But in the hotter, drier valleys and foothills cloaked in grass, oak, and chaparral, human behavior dominates. Through arson or accident, in southern California, over 95% of fires are started by people, according to Cal Fire.

"Climate change is certainly important on some landscapes. But at lower elevation, we should not be thinking just about climate change," said Keeley. "We should be thinking about all global change." Land use change and population growth create more opportunities for fires to start.

The high frequency of fire has instigated a persistent switch from chaparral to grass in some areas. Frequent fire favors quick germination and spread of forbs and grasses. Most grasslands in California are not native.

Since the more recent arrival of immigrants from Europe and Asia, several of the exotic grasses they brought with them from the Old World have been quick to capitalize on the opportunities presented by fires to spread invasively throughout roughly a quarter of chaparral country. To Keeley, this means that prescribed fires in lower elevation ecosystems now have entirely different consequences for the regional ecology than they did when native Californian peoples set fires to manipulate resources.

"When the Native Americans did it, they did not affect native species so much, because native perennial bunchgrass and other herbaceous species grew in," said Keeley. "Once the aliens got here, it completely changed."


'/>"/>

Contact: Liza Lester
llester@esa.org
202-833-8773 x211
Ecological Society of America
Source:Eurekalert

Related biology news :

1. Scientists trace evolutionary history of what mammals eat
2. Family history of liver cancer increases risk of developing the disease
3. Earth history and evolution
4. New coelacanth find rewrites history of the ancient fish
5. Biology professor secures grant to save West Virginias primary natural history collection
6. Honoring the fundamental role of microbes in the natural history of our planet
7. New report puts real numbers behind history of oyster reefs
8. IU role in Human Microbiome Project exposes battle history between bacteria, viruses in human body
9. Short stretches of piRNA evaluate cells genetic history
10. Bringing natural history collections out of the dark
11. Geologys Mystery Interval, the Great Deepening, and the largest kill-off in Earth history
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/30/2017)... Va. , June 30, 2017 ... leading developer and supplier of face and eye ... ATA Featured Product provider program. ... an innovative way to monitor a driver,s attentiveness ... greatly from being able to detect fatigue and ...
(Date:5/16/2017)... DALLAS , May 16, 2017   ... for health organizations, and MD EMR Systems ... certified development partner for GE, have established a ... Patient Portal product and the GE Centricity™ products, ... Centricity EMR. These new integrations ...
(Date:4/17/2017)... 17, 2017 NXT-ID, Inc. (NASDAQ: NXTD ... filing of its 2016 Annual Report on Form 10-K on Thursday ... ... available in the Investor Relations section of the Company,s website at ... website at http://www.sec.gov . 2016 Year Highlights: ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... The CRISPR-Cas9 ... enabling overexpression experiments and avoiding the use of exogenous expression plasmids. The simplicity ... for performing systematic gain-of-function studies. , This complement to loss-of-function studies, such ...
(Date:10/11/2017)... ... 2017 , ... ComplianceOnline’s Medical Device Summit is back for its 4th year. ... San Francisco, CA. The Summit brings together current and former FDA office bearers, regulators, ... government officials from around the world to address key issues in device compliance, quality ...
(Date:10/11/2017)... , Oct. 11, 2017  VMS BioMarketing, a leading provider ... nationwide oncology Clinical Nurse Educator (CNE) network, which will launch ... for communication among health care professionals to enhance the patient ... office staff, and other health care professionals to help women ... cancer. ...
(Date:10/11/2017)... ... October 11, 2017 , ... Disappearing forests and increased emissions are the ... million people each year. Especially those living in larger cities are affected by air ... one of the most pollution-affected countries globally - decided to take action. , “I ...
Breaking Biology Technology: