FIRE AND ENVIRONMENTAL CHANGE IN TROPICAL ECOSYSTEMS

FIRE DANGER RATING in TROPICAL ECOSYSTEMS

USDA Forest Service, FERA: David V. Sandberg, Ernesto Alvarado, Roger D. Ottmar Robert Vihnanek

Instituto Nacional de Pesquisas Espacias, Brasil: Joao Andrade de Carvalho Junior

Instituto Brasiliero do Meio Ambiente: Selma Bara Melgaco

University of Brasilia; Heloisa Miranda

Tropical Forestry Foundation: Johan Zweede

October 30, 1999

Fire danger rating in tropical ecosystems is needed in order to anticipate and manage unusually severe fire seasons, to support regulation of burning practices, and to assess the impact of land use and climate change on the rate of savannazation of tropical forests. This project is developing a danger rating system that will quantify the level of anticipated fire hazard in the cerrado and tropical forests of Brazil.

Fire danger is made up of the combination of Risk, defined as the likelihood that ignition will occur and the human consequences of fire, and Hazard, defined as the fire intensity, severity, and the effects of fire on ecosystems. Fire risk is being investigated by the Woods Hole Research Institute, in cooperation with IBAMA and USAID. Fire risk depends primarily on land use practices and demographics.

Fire Hazard Rating is being assessed by the Fire and Environmental Applications Team of the USDA Forest Service, in collaboration with International Programs, USAID, the Tropical Forestry Foundation, the Instituto Nacional de Pesquisas Espacias, University of Brasilia, IBAMA, and PREVFOGO.

Fire hazard is determined primarily by vegetation cover, fuelbed characteristics, and meteorology. Our objective is to identify the conditions that define the important thresholds of fire spread, fire intensity and fire severity in important fuel types in Brazil. To this end, we are conducting a series of field experiments to measure vegetation cover, fuel characteristics, meteorology, fuel moisture conditions, flammability, biomass consumption by fire, and ecological effects.

The important input variables are:

Fuel Moisture Conditions

• Fuelbed Characteristics
  
• Canopy Conditions
  
• Daily Relative Humidity
  
• Precipitation History
  

Research and development to support this project is being carried out at:

• Tropical Forest Sites:

  • Fazenda Caiabi, Alta Floresta, Mato Grosso (Primary and Harvested Forest)
    
  • Floresta Tapajos, Santarem, Para (Low-Impact Harvest and Traditional Harvest)
    
  • Cauaxi, Para (proposed Low-Impact Harvest and Traditional Harvest, with TFF)
    

• Cerrado/Campo Sites:
  • Reserva IGBE (Campo)
  • Parque Nacional das Emas, Goias (Cerrado)
  • Chapada da Diamantina, Bahia (Cerrado, Cerradao