The cough-inducing haze eventually will clear, but Southern California's recent wildfires could lead to longer-lasting environmental consequences -- mudslides that send ash-ridden water to the ocean and the extinction of a few plants and wildlife.
And in areas especially hard hit by fire, chaparral might never grow back, making it tough for other plants and animals within a charred, altered ecosystem.
"If you have too-frequent fire, your vegetation may not recover from fire and you can end up losing species," said Scott Morrison, a scientist with the Nature Conservancy. "A lot of the natural environment will recover on its own. What we want to be on the lookout for are those places that are going to need some help."
With nearly two dozen wildfires burning in recent days, Southern California has seen more than 517,700 acres and more than 2,000 homes burn. Now that many of the fires are out or contained, environmentalists are assessing the damage to the natural landscape.
After a wildfire, officials always prepare for the threat of mudslides on hills denuded by the flames.
"In terms of watersheds, erosion is a big worry if you've got hillsides without live vegetation," said Bill Rukeyser, a spokesman for the State Water Resources Control Board.
And if too much nutrient-rich ash and silt gets into waterways and out to the ocean, it can cause algae to grow, which hurts fish, Rukeyser said.
To prevent the threat of erosion and runoff, workers in the coming weeks will put down sandbags or turn fallen trees sideways to slow water flowing downhill. In U.S. Forest Service land, some of the same firefighters who were battling the flames will be setting up bales of hay to prevent runoff.
In San Diego County, the Quino checkerspot butterfly and the Thorne's hairstreak butterfly are in danger of extinction because of frequent fires that have recently burned through their habitat, Morrison said.
The Tecate cypress, a rare tree found in the Otay Mountains near the border with Mexico, could also be at risk, he said.
But for other species, the news might not be so dire. In fact, the wildfires could be a boon.
Coyotes often eat smaller prey that has been left disoriented by flames. A bird called the rock wren has been known to settle in areas stripped of plants and trees, nesting in rock outcroppings.
"Some things die, but then other species benefit and probably their populations go up," said Ian Swift, director of the Placerita Canyon Nature Center in Newhall.
Wildlife managers were particularly concerned about populations of big-horn sheep and a few young California condors, but those animals appear to have made it through OK.
Some plants called "fire followers" will grow back by spring in areas that have burned, Swift said. Larger shrubs will grow back within five years, he said.
The California Department of Fish and Game will evaluate the burned areas, using satellite images and aerial photos to determine whether anything should be done to help species affected by the fires, said Harry Morse, a spokesman for the department.
Meanwhile, in heavily populated coastal areas, fires have been occurring too frequently, and that is harming the environment, experts said.
Near Pepperdine University in Malibu, some chaparral -- the thicket of shrubs and thorny bushes native to Southern California -- has been unable to grow back because of frequent fires, said Suzanne Goode, senior environmental scientist with California State Parks.
Laurel sumac, weeds and mustard grass have grown in place of the chaparral, and they are more flammable.
"Increasing fire frequency causes increasing fire frequency," Goode said.
Plants that emerge after a fire don't hold the soil as well as chaparral, which leads to erosion -- especially with heavy rain -- and harms rivers and streams.
"So the whole ecosystem starts to really deteriorate," Goode said.
A similar process of vegetation changing to more flammable plants has been at work along coastal Orange County and in parts of Los Angeles County inland from Malibu.
"It is a really serious condition from an ecosystem point of view," said Pepperdine professor Stephen Davis, a plant ecologist who has studied the process.
While the ash from burned vegetation is relatively clean, officials warned that burned homes could be toxic and include asbestos.
"Any structure that is burned, it's a good idea to assume the resulting ash has hazardous material," Rukeyser said.
As for the air quality, the health threat will be nearly eliminated within days of the fires being put out, South Coast Air Quality Management District officials said. Winds eventually will blow the bad air east over the Rocky Mountains.
On Monday, the AQMD said air quality had improved in most areas, but that it remained unhealthful near the remaining wildfires.
And while some blame the wildfires for all the environmental hazards that have resulted, some think we need more fires to let nature take its course.
Richard Minnich, a geography professor at the University of California, Riverside, argues that in Baja California, where firefighters purposely don't battle wildfires as hard as in Southern California, frequent but less dramatic blazes thin out the vegetation and prevent the kinds of destruction seen here in recent days.
Minnich advocates letting wildfires burn out naturally.
"Look, fire is inevitable, it's like breathing -- in fact they're the same process, it's called oxidation," he said. "The public has to understand this process is going to happen."Los Angeles Daily News via AZcentral.com
