soil fire

what is the mechanism for soil to dry out

evaporation and transpiration

what are the four key factors influencing forest fires

ignition, weather, fuel, humans

what weather variables influence fire behaviour

temperature, precipitation, atmospheric moisture, wind, upper atmosphere conditions

what fuel characteristics matter for fire

fuel loading, moisture content, structure, arrangement

how do humans influence fire risk

land use, fragmentation, fire suppression/management, infrastructure

what are the inputs in the fine fuel moisture code

temp, relative humidity, wind, rain

what are the inputs in the duff moisture code

temp, relative humidity, rain

what are the inputs in the drought code

temp, rain

what is the fine fuel moisture code

moisture content of litter and other fine fuels

what is the duff moisture code

loosely compacted, decomposing OM

what is the drought code

deep layer of compact OM

what are major ignition sources

lightning, humans, infrastructure

what is dry lightning

lightning with little or no rain; high fire risk when fuels are dry

in canada, what % of fires are caused by lightning and what % of area burned do they cause

45% of fires; 80% of area burned

why do some lightning strikes fail to ignite fires

if thunderstorms bring rain, fuels become wet and ignition fizzles out

how was fire traditionally used by indigenous peoples

as an ecological management tool based on local knowledge

what are examples of indigenous fire uses

managing prairie grasslands, shaping forest landscapes, improving habitat, aiding hunting

what does LFH stand for in forest soils and what is that layer called

litter, fermented, humus - duff layer

how do soil depths differ between shield and plains regions

• shield: thin soils over bedrock

• plains: deeper soils

what are the steps in fire management

• monitor weather and risk

• identify values at risk

are all fires suppressed

no - remote fires are not suppressed

what is spot fire ignition

a small ignition point caused by humans or lightning

what are campaign fires

large, long duration fires required sustained, strategic suppression

what are values at risk

humans, buildings, infrastructure, timber, biodiversity

what are fuel management options

• reduce the fuel (mechanical, burning)

• conversion of fuel type (deciduous holds moisture)

• isolate continuous fuels

what is the forest life cycle

1. decomposition (woody debris, regeneration)

2. successional vegetation to crown closure

3. renewed mature forest stand

4. combustion losses - co2, co, ch4