Download
introduction to fire and prescribed fire use n.
Skip this Video
Loading SlideShow in 5 Seconds..
Introduction to Fire and Prescribed Fire Use PowerPoint Presentation
Download Presentation
Introduction to Fire and Prescribed Fire Use

Introduction to Fire and Prescribed Fire Use

560 Vues Download Presentation
Télécharger la présentation

Introduction to Fire and Prescribed Fire Use

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Introduction to Fire and Prescribed Fire Use Fire Ecology and Management Jan. 7, 2011

  2. Outline • Perspectives on fire • History of fire in the US • Florida’s fire imperative • Intro. to fire regimes & fire ecology • Prescribed burning primer • How to use fire to perpetuate native ecosystems • SAFETY

  3. 1 During

  4. 1 After

  5. 2 During

  6. 2 During

  7. 2 After

  8. 2…3 months After

  9. 3 During

  10. 3 After

  11. 4 During

  12. 4 After

  13. Is fire good or bad?Natural or not?How did we get to where we are today?History of Fire in the US and Florida

  14. Plant & animal communities evolved in the presence of intermittent fires. Lightning-ignited fires have been burning the planet for more than 400 million years. • In North America, Native Americans have been lighting vegetation fires for >12,000 years. • Stimulate forage production for game, game herding, clearing ag. Land, territory marking, signaling

  15. Brief history of fire in the US & Florida • DeSoto, 1538 landed in Tampa Bay, traveled with 600 men, and enough swine to feed them to Tallahassee…how? From Lake City to Tallahassee, the forest was open– reports chronicle cleared land, plains, cultivated fields, open forests, and recently-burned lands • “thickly settled in numerous towns with field extending from one to the other, a pleasant place with fertile soil and good meadows…with many corn fields…” • Fields alongside most major rivers (Coosa, Mississippi, Tombigbee, Chattahoochee • Early settlers emulated Native American fire use (1600s-1800s) • Clearing land, stimulating forage production for game, recycling nutrients, site preparation

  16. Legacy of NA Fire Use in SE Forests: good fires • Major results of repeated burning– forest structure & composition • Helped perpetuate “park-like” forests, pruned lower branches • Navigable and open with little regeneration or small trees • Selected for fire-resistant or fire-dependent species

  17. Legacy of NA Fire Use: They knew that frequency matters • Frequency • “Cereal grasses were fired annually, basket grasses and nuts about every 3 yrs., brush and undergrowth about every 7-10 yrs., large timber every 15-30 yrs. or more; and broadcast fire in the fields on an annual basis got rid of vermin, disease, weeds, and regrowth,” (Williams, 1999)

  18. Legacy of NA Fire Use in SE Forests- Season matters, too (sandhill/ high pine) • Growing season burns stimulate wiregrass seeding • Wiregrass attracts browsing animals and birds, improves habitat for rare species • Fire “selects for” longleaf pine seedlings over other young trees • Fire-maintained, human-maintained, or both? Natural or not?

  19. The era of fire suppression: Fires are bad! • Peshtigo, WI fires of 1871 (1200-2400 lives) • Great Idaho fires 1911 (3 Mil. Acres, 78 people) • Gifford Pinchot proclaims forests must be protected from fire to preserve grazing and timber • Propaganda…and science! USFS removes references to beneficial uses of fire • Weeks Act 1911, provides $ for states to fund firefighting • 1916 National fire suppression policy instated • 10 AM Policy of 1935

  20. “Land management is an art that builds on history and is based in science." (Stoddard) Vs. • “Renegade” prescribed burning programs in SE, early 1900s (HH Chapman- Yale) ~1920-60s (Herbert Stoddard, bobwhite quail, GA) • Response: Dixie Crusaders in SE US; 1928-1931 • USFS propaganda- fires are lower class…

  21. USFS Psychologist Dr. Shea published an article in American Forests 1940, titled "Our Pappies Burned the Woods," where he was quoted: “…burning the woods] has become predominantly a recreational and emotional impulse... the sight and sound and odor of burning woods provide excitement for a people who dwell in an environment of low stimulation.... Their explanations that woods fires kill off snakes, boll weevil and serve other economic ends are something more than mere ignorance. They are the defensive beliefs of a disadvantaged culture group." Herbert Stoddard: “…the magnificent virgin stands of southeastern pines, included frequent burning, carefully controlled fire for the benefit of animal life…In our opinion, to exclude fire permanently from the park-like pinelands of the Southeast is to jeopardize both the flora and fauna and to contribute to their replacement by other and inferior types of animal life and vegetation. How many who are advocating total fire exclusion in this region have seriously considered the consequences of disturbing this age-old adjustment?“ (Tall Timbers Research Station 1961, p.197)

  22. By 1943, with Stoddard’s help and after farmers’ complaints about losses to wildfires due to fuel load build-up, USFS approved “controlled burning” • Rx fire re-incorporated into land management in SE earlier than elsewhere • Leopold Report: 1963 in the Western National Park System: “Let Burn Policy”, 1968 • By 1990s, National Fire Policy included prescribed fire or “wildland fire use” • Today, the SE leads the nation with >3 Million acres annually burned for fuels mitigation, restoration, & natural resource benefits Loblolly pine, SC 1958 Photo: Nobles/ Ramierez Ocala NF, FL 2009

  23. The Legacy of Fire Suppression • Fuel load build-up • Larger, less predicable, more costly • Higher severity, especially of overstory spp. • From mid-1800s to today, active fire suppression, agriculture, grazing, and intensive land use practices altered historical fire regimes. • Altered fire regimes have substantially changed ecosystem composition, structure, and function, along with the effects fires can have on ecosystems.

  24. How do we describe fire? • Fire Regimes: Attributes that describe how fire has influenced ecosystems fairly consistently over time, and in relation to other factors (e.g. climate) • Often used to reach the “desired future condition” in restoration • Fire type (crown, surface, ground) • Area burned, spatial extent • Seasonality • Severity • Synergism ? • Fire frequency (fire return interval)

  25. Frequent fire Infrequent fire Randy Cyr Longleaf pine forests Southeastern US Fire 1-4 years Low intensity, understory, summer Bald Cypress/ tupelo swamp Fire > 200 years, small area Mixed severity, only during drought (peaty soils) Florida Big Scrub (sand pine) Fire 25-100+ years, high intensity, crown, spring or summer, large areas Examples of FL Fire Regimes

  26. Florida’s Fire Imperative • The Florida Natural Areas Inventory lists 23 terrestrial, 19 wetland communities in Florida: 16 of these are considered FIRE DEPENDANT– and will change significantly if historical fire regime is altered • What are the most important aspects of fire regime in Florida, which often determine the rest of the regime?? • Sandhill FRI 1-7 yrs • Dry & Wet Prairie FRI 2-7 yrs • Mesic Flatwoods FRI 3-7 yrs in N. FL, 1-7 in SFL • Scrubby Flatwoods FRI 8-25 yrs • Swamp FRI 8-100+ yrs • Scrub FRI 26-100+ yrs

  27. Lightning is itself an imperative

  28. The basis for (successful) fire management is an understanding of historical fire regimes and the fire ecology on which they are predicated Informs how, what, when, and why…and what if fire is NOT applied to a given system

  29. If Fire is Absent? • Most Florida ecosystems transition to shrub-hardwood communities • Spatial diversity and mosaic of communities disappears • Wildfires become more intense • Overstory killed • Soil damage

  30. If Fire is Absent? • Vegetation • tree density & cover increase • composition shifts to shade tolerant species • growth rates & tree vigor decline • herbaceous forage and shrubs decline • Soils • organic matter accumulates • nutrient cycles slow

  31. If Fire is Absent? • Animals • late successional species replace seral species • populations of many species decline • endemic insects & diseases increase • Ecosystem processes • tend to simplify in structure & function • stream flow & on-site water balance decrease • potential for large fires increases

  32. Fire management is applied fire ecology

  33. Ecological Effects of FireBasic Premises • All ecosystems change over time (even the old-growth!) • Fire is neither innately destructive nor constructive, it simply causes change (Wade 1983) • Human perception of whether it is good or bad depends on their resource objectives

  34. MASTICATEDVEG. Fire Ecology…coming soon • Fire effects on soils, water, air, nutrients, carbon, cycles, geomorphology • Paleoecology and Fire history • Fire adaptations, resistance, and resilience ATMOSPHERIC CO2 AUTOTROPHIC CO2 HETEROTROPHIC CO2 FOREST FLOOR DUFF & LITTER SOIL BOUNDARY SOIL FUNGI, BACTERIA MICRO/ MACROFAUNA

  35. BREAK TIME!

  36. Introduction to Prescribed Fire Use Foundations in Forest Resources and Conservation July 29, 2008

  37. What is fire? Energy release in the form of heat and light when oxygen combines with a combustible material (fuel) at a suitably high temperature The fire Triangle Oxygen Heat Fuel

  38. What does that mean for you as a fire user? A firefighter?

  39. Fire Science • Understanding how to use fire, and the effects it has on ecosystems, depends on a basic understanding of fire itself • Methods of heat transfer • Radiation • Convection • Conduction • Phases of combustion and their consequences • Fire behavior- rate of spread, flame length, intensity, residence time, temperature…

  40. What dictates fire behavior–the fire behavior triangle 1. Weather 2. Fuels 3. Topography

  41. 1. Weather (preferences for winter Rx fire in SE US) • Temperature (< 60) • Relative Humidity (30-55%) • Fine fuel moisture 10-20% • Wind speed (in stand 1-3 mph) • Mixing height (1700-6500’) • Atmospheric stability (resistance of atmosphere to vertical motion– slightly unstable or neutral) • Drought indices (KBDI below 400)

  42. Keetch-Byram Drought Index (KBDI)

  43. Okefenokee Swamp/ Big Turnaround Complex, N FL and S GA, May 2007

  44. Season matters!

  45. Today’s weather…(NWS) Red Flag Warning 000 WWUS82 KJAX 060930 RFWJAX URGENT - FIRE WEATHER MESSAGE NATIONAL WEATHER SERVICE JACKSONVILLE FL 430 AM EST THU JAN 6 2011 FLZ020>025-030>033-035>038-040-062100- /O.NEW.KJAX.FW.A.0002.110107T1800Z-110107T2300Z/ HAMILTON-SUWANNEE-COLUMBIA-BAKER-NASSAU-DUVAL-UNION-BRADFORD-CLAY- ST JOHNS-GILCHRIST-ALACHUA-PUTNAM-FLAGLER-MARION- 430 AM EST THU JAN 6 2011 ... FIRE WEATHER WATCH IN EFFECT FRIDAY AFTERNOON FOR BREEZY WINDS AND LOW RELATIVE HUMIDITIES... THE NATIONAL WEATHER SERVICE IN JACKSONVILLE HAS ISSUED A FIRE WEATHER WATCH...WHICH IS IN EFFECT FRIDAY AFTERNOON. BREEZY WEST TO NORTHWEST FLOW COMBINED WITH DRY AIR FOLLOWING A FRONTAL PASSAGE MAY SUPPORT RED FLAG CONDITIONS ACROSS INLAND NORTHEAST FLORIDA FRIDAY AFTERNOON. SUSTAINED WINDS WILL NEAR 15 MPH WITH GUSTS TO 20 TO 25 MPH POSSIBLE. MINIMUM RELATIVE HUMIDITIES ARE EXPECTED TO NEAR 30 TO 35 PERCENT FOR BRIEF DURATIONS IN CONCERT WITH BREEZY WINDS. A FIRE WEATHER WATCH HAS BEEN ISSUED. PRECAUTIONARY/PREPAREDNESS ACTIONS... A FIRE WEATHER WATCH MEANS THAT CRITICAL FIRE WEATHER CONDITIONS ARE FORECAST TO OCCUR. LISTEN FOR LATER FORECASTS AND POSSIBLE RED FLAG WARNINGS. &&

  46. 2. Four general fuel groups Anderson, 1982

  47. Orientation divides 4 groups Anderson, 1982

  48. The 13 fuel models