Fire issues in California's Central Coast Region

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A watershed-related topic examined by the ENVS 560/L Watershed Systems class at CSUMB.

Image 1. Flames engulf a hillside of chaparral in Palo Colorado Canyon during the Soberness Fire of 2016. Photo by David Royal.

Summary

Wildfire presents various challenges and benefits to the people and ecosystems of the Central Coast Region. As California's population grows, urban expansion into natural areas is becoming more commonplace, exposing people to increasing risk in the event of fire. Years of fire suppression, coupled with prolonged drought conditions, have changed the local fire regime[1], yielding an even greater challenge when it comes to mitigating damage to both ecosystems and man-made infrastructure.

Fire Management

Historically, lightning fires and purposeful ignitions by indigenous tribes ensured rather frequent fires of low to moderate severity.[2] In the early part of the 20th century, United States land managers generally believed that fire exclusion promoted ecological stability. It wasn't until the mid 1960s that fire was shown to provide ecological benefits, resulting in gradual shifts in fire management policy to allow more fires to take their natural course.[3] As a result of changing policies and shifts in climatic patterns in the western U.S., large wildfire frequency and duration has increased and wildfire seasons have lengthened since 1970.[4] Most recently, federal fire management policy has emphasized fuels management treatments such as prescribed burns and mechanical thinning to prevent catastrophic wildfires.[3]


Due to the close proximity of different land jurisdictions on the Central Coast, fire management often involves multiple agencies including but not limited to: the Forest Service, CalFire, California State Parks, Bureau of Land Management, individual counties, California Department of Fish and Wildlife, volunteer fire brigades and other entities that manage open space or rural areas.

Cost of Fire Management

The cost of fighting wildfires is already exorbitant and is quickly rising. For example, in 2015 more than 50 percent of the U.S. Forest Service's federal budget of approximately $6.5 billion went to wildfire management, up from 16 percent in 1995. This change in funding allocation is directly responsible for defunding other Forest Service departments such as recreation, restoration, and planning.[5][6]

In California, the state fire management agency budget is one of the highest in the nation. The California Department of Forestry and Fire Protection, or CalFire, is California's fire response agency charged with managing wildfires on private land. Their budget for Fiscal Year 2016-2017 was reported at approximately $3.2 billion.[7]

Benefits of Fire

Image 2. California condor #167 in a burned out redwood cavity in Big Sur, CA, on 28 March 2006, Photo by Joseph Brandt, Ventana Wildlife Society.

Native ecosystems on the Central Coast have adapted to fire over time.[8][9]The following is a list of some of the many benefits fire can provide to the area:

  • Growth stimulation of native plants: The chaparral, oak woodland, redwood forest, and grassland ecosystems - all characteristic of the region - are well-adapted to fire. Many plants in these ecosystems depend on wildfire for germination cues, restarting the succession cycle, protection against disease, and making nutrients available for uptake.[10]
  • Replenishment of sand for river and ocean beaches: Steep, fractured, granitic slopes characteristic of the coastal mountain ranges erode easily, especially when saturated. If a fire has burned the vegetation in the area, and damaged root systems that help stabilize soil, larger than normal debris flows and landslides can occur during the rainy season. Although these processes can pose inconveniences to humans living in affected watersheds, fluvial sediment transport is the main mode of beach sand replenishment on the West Coast. Therefore, fires play an instrumental role in ensuring beach sustainability.[11]
  • Creation of habitat: Fire generally burns in irregular patterns and varies in intensity. The mosaic that results destroys habitat for some animals while creating habitat for others. Cavity nesters, or birds that live in holes in trees, often benefit from fire. One such bird is the endangered California condor whose range is slowly being reestablished on the Central Coast. The wide cavities created by fire in the tops of redwood trees have served as ideal nesting spots for multiple condors on the Big Sur coast (Image 2).[12]

Negative Impacts of Fire

Hot, dry conditions on the Central Coast during late spring, summer and fall contribute to fire risk. In the fall and early winter, it's not atypical for Santa Ana winds to fan and spread active fires.[13] This combination of high temperatures and warm winds contributes to increasing flammability of dead and live fuel sources and is often exacerbated by drought conditions, which sometimes leads to "catastrophic" wildfires.[4]

Wildfires can negatively impact ecosystems in a variety of ways:

  • Ecosystem type conversion: Today's transportation technology allows for people to travel far distances in a relatively short amounts of time. Because of this capability, certain historical biogeographical barriers have been broken down, exposing native ecosystems to a variety of pathogens and exotic plant and animal species that would not otherwise be in a given location. Type conversion, or the conversion of chaparral ecosystems to nonnative grassland, is becoming more common in Central California in the wake of fire.[14] This poses a threat to native flora and fauna because biological invasions have been documented to cause species extinctions and disruptive changes in ecosystem function.[15]
  • Increased turbidity: Turbidity, or the murkiness of water caused by fine, suspended sediment, increases during storm events. When large rainstorms occur on the Central Coast after fire has burned the land, affected watersheds often experience spikes in turbidity. Many of the coastal streams serve as important spawning habitat for endemic steelhead populations. Steelhead are sensitive to turbidity levels because fine sediment can interfere with gill function.[16] Additionally, sediment transport during post-fire rain events can scour steelhead redds (egg deposits) or cover eggs with fine sediment and starve developing embryos of oxygen.[17]
  • Crown Fires: Crown fires are considered those that completely burn stands of trees, including the tops of trees (or crowns). Some forest types can take a very long time to regenerate after crown fires. Although crown fires can occur on the Central Coast, the effects of severe fires generally persist for a relatively short amount of time (about 2 to 3 years).[18]
  • Geologic changes: Vegetation plays a major role in maintaining slopes and drainage areas, keeping structure of the soil steady and providing overall landscape stability. Without this vegetation, processes like rock falls, debris slides and flows, dry ravel, surface erosion and gullying will worsen in accordance with burn severity during storm flows.[19] Soil hydraulic conductivity can also be affected depending on the severity of the burn. Severely burned soils have a high degree of hydrophobicity which decreases the infiltration rate of rainfall and, in turn, increases erosion rates and overland flow. The eroded material has the potential to increase sedimentation in streams affecting water quality and flow.[20]

Challenges for Humans in the Wake of Fire

At the end of the 19th and the beginning of the 20th century, the U.S. experienced a number of wildfires in a short amount of time that caused multiple human fatalities, spurring the general view that wildfires are dangerous and unwanted.[3] The loss of human life, infrastructure, and possessions that wild fire can cause presents many challenges. The following is a list of some of the difficulties that arise in the wake of fire:

  • Increased burden of cost on California taxpayers for increasing fire management needs
  • Loss in tourism for affected areas
  • Mudslides and debris flows can impede access to whole communities and rural homes
  • Home and life loss
  • Increased flood risk post fire
  • Decrease in air quality for duration of fire

Scientific Research with Regards to Fire

Major Fires since 1970 that Have Affected the Central Coast

Links

References

  1. Greenlee JM, Langenheim JH. 1990. Historic fire regimes and their relation to vegetation patterns in the Monterey Bay Area of California. The American Midland Naturalist 124(2):239-53. doi:10.2307/2426173.
  2. Keeley JE. 2002. Native American impacts on fire regimes of the California coastal ranges. Journal of Biogeography, 29(3):303-320.
  3. 3.0 3.1 3.2 (NPS & USFS) National Park Service and United States Forest Service. 2001. Review and Update of the 1995 Federal Wildland Fire Management Policy. (Internet). (cited 2017 April 05).
  4. 4.0 4.1 Westerling AL, Hidalgo HG, Cayan DR, Swetnam TW. 2006. Warming and earlier spring increase western US forest wildfire activity. Science, 313(5789):940-943.
  5. (USDA) United States Forest Service. 2014. Fiscal Year 2015 Budget Overview. (Internet). (cited 2017 April 05).
  6. (USDA) United States Forest Service. 2015. The rising cost of wildfire operations: effects of the Forest Service's no-fire work. (Internet). (cited 2017 April 05).
  7. (CalFire) California Department of Forestry and Fire Protection. 2016. CalFire at a glance. (Internet). (cited 2017 April 05)
  8. Stephens SL, Fry DL. 2005. Fire history in coast redwood stands in the northeastern Santa Cruz Mountains, California. Fire Ecology,1(1):2-19.
  9. (USFS) Fried JS, Bollinger CL, Beardsley D. 2004. Chaparral in southern and central coastal California in the mid-1990s: area, ownership, condition, and change. PNW-RB-240. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 86 p.
  10. Hanes TL. 1971. Succession after Fire in the Chaparral of Southern California. Ecological Monographs, 41(1)): 27-52. doi:10.2307/1942434.
  11. Willis CM, Griggs GB. 2003. Reductions in fluvial sediment discharge by coastal dams in California and implications for beach sustainability. The Journal of Geology, 111(2):167-182.
  12. Burnett LJ, Sorenson KJ, Brandt J, Sandhaus EA, Ciani D, Clark M, David C, Theule J, Kasielke S, Risebrough RW. 2013 Eggshell thinning and depressed hatching success of California Condors reintroduced to central California. The Condor, 115(3):477-491.
  13. Westerling AL, Cayan DR, Brown TJ, Hall BL, Riddle LG. 2004. Climate, Santa Ana winds and autumn wildfires in southern California. Eos, 85(31):289-296.
  14. Fire Ecology in the Santa Monica Mountains, National Recreation Area
  15. D'Antonio CM, Vitousek PM.1992. Biological invasions by exotic grasses, the grass/fire cycle, and global change. Annual review of ecology and systematics, 23(1):63-87.
  16. Mulvey M, Borisenko AN, State of Oregon Department of Environmental Quality. 2008. Lower Columbia Wadeable Streams Conditions Report. (Internet). (cited 2017 April 05).
  17. Lisle TE. 1989. Sediment transport and resulting deposition in spawning gravels, north coastal California. Water resources research, 25(6):1303-1319.
  18. Keeley JE, Brennan T, Pfaff AH. 2008 Fire severity and ecosytem responses following crown fires in California shrublands. Ecological Applications, 18(6):1530-1546.
  19. Schwartz JY, King A. 2016. Burned Area Emergency Response (BAER) Assessment FINAL Specialist Report – GEOLOGIC HAZARDS, Soberanes Fire –Los Padres N.F.
  20. Rocky Mountain Research Station, Air, Water, and Aquatic Environments Program. 2014. Wildfire Impacts on Stream Sedimentation. Science Briefing
  21. Watson F, Angelo M, Anderson T, Casagrande J, Kozlowski D, Newman W, Hager J, Smith D, Curry B. 2003. Salinas Valley Sediment Sources. The Watershed Institute, California State University Monterey Bay, Publication No. WI-2003-06, 227 pp.

Disclaimer

This page contains student work completed as part of assigned coursework. It may not be accurate. It does not necessary reflect the opinion or policy of CSUMB, its staff, or students.