HOME >> BIOLOGY >> NEWS
USGS studies wildfire ecology in the western United States

res of shrubland present in the National Conservation Area in 1979, only 46,000 hectares remain.

To put it simply, Knick says, the shrubland is burning up. Wildfire incidence has increased by a factor of three since 1980, and fires are getting larger. But behind this increase -- and in turn capitalizing on it -- is the fast-spreading, exotic annual grass. "It's a synergistic thing," says Knick. "Cheatgrass promotes fire spread, and the larger fires eliminate more shrubs."

Knick says that fire has always been a factor in sagebrush ecosystems, creating openings in the shrub canopy and constraining the density of woody plants much the same as in forests. But an understory of native bunch grasses, which grow in isolated patches, tends to limit the intensity of blazes in these systems and prevent them from spreading over a wide area.

Cheatgrass, which has been advancing since the early 1900s, in part due to overgrazing and drought, creates a continuous carpet of fuel. And cheatgrass thrives on recently burned land, thus perpetuating the altered fire regime. If the shrubs in an area don't have time to recover before the next fire hits, they eventually disappear. "Fire has gone from maintaining a shrubland, to destroying a shrubland, to ultimately maintaining an exotic grassland," Knick says.

Using data from a number of sources including satellite imagery, historical records of fire frequency and behavior, and ground measurements of vegetation, Knick's team has developed a computer model for predicting long-term changes resulting from different scenarios of burning and regeneration of vegetation. The model shows that in shrublands with a cheatgrass understory, fire can easily trigger a rapid transition to grassland. But once established, these grassland systems tend to be relatively stable, even when fire is suppressed.

"The daunting thing is that it's going to take a long time to replace what has been destroyed in the last 20 y
'"/>

Contact: Catherine Haecker
catherine_haecker@usgs.gov
707-826-5645
United States Geological Survey
17-Sep-1999


Page: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Related biology news :

1. Rensselaer marks the opening of the center for biotechnology and interdisciplinary studies
2. UCSD undergraduates participate in collaborative studies abroad on cyberinfrastructure
3. Scientist honored for studies of genetic influence on chemotherapy, tumor development
4. $5 million grant funds partnership, studies of minority-based issues in reproductive health
5. Synthetic hormone used in contraceptives and HRT produces negative effects in monkey studies
6. $5.5 million awarded to tree-ring research and climate studies
7. Pancreatic cancer blood test & gene studies show promise
8. Two studies weigh in on low-carb diets
9. Animal studies show promise treating severe chronic pain
10. New studies show Curves Program raises metabolic rate in overweight and sedentary women
11. Florida Tech researchers win $912,700 grant for cell studies

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:9/22/2018)... ... September 20, 2018 , ... We are excited to announce ... the recently launched NovoCyte QuanteonTM flow cytometers and NovoSampler® ... , In addition to the functionalities supporting the expanded flow ...
(Date:9/22/2018)... ... September 21, 2018 , ... VTE can ... untreated, can lead to significant morbidity and mortality. VTE affects between 300-600,000 Americans ... autopsy. Further, PE is the leading cause of preventable hospital death and maternal ...
(Date:9/12/2018)... ... September 10, 2018 , ... IONpathTM, a venture-backed ... new Multiplexed Ion Beam Imaging (MIBITM) technology was accepted by the journal Cell ... be shared during a webinar presented by Dr. Mike Angelo on October 2nd, ...
Breaking Biology News(10 mins):
(Date:9/7/2018)... ... September 05, 2018 , ... Now available on live stream, the NanoScientific ... Sept. 19, 2018. With a panel of industry leaders from Harvard, Cornell, RPI, IBM, ... industry insights from experts in the field. Register today to be a part ...
(Date:9/7/2018)... ... 2018 , ... Akadeum Life Sciences today announced it has appointed George Dunbar ... leader of numerous biotech companies. , He most recently served as president and ... Street Capital in St. Louis, MO. Prior to ISTO, he was a Venture ...
(Date:8/29/2018)... ... August 28, 2018 , ... ... announced today the successful completion of a $5.5 million funding round managed by ... Investment Fund, Commenda Capital, and Ellipsis Ventures. , “Our investment in Nanovis is ...
(Date:8/29/2018)... , ... August 28, 2018 , ... LabRoots , ... around the world, is proud to announce the launch of a new gamification feature, ... a chance to win one of LabRoots most popular shirts. , Throughout each month, ...
Breaking Biology Technology:
Cached News: