Fire

Question 1

What conditions are needed for fires?

Answer 1

Dry weather
Fuel
Ignition (e.g. lightning or humans)

Question 2

What are crown fires?

Answer 2

Fire climbs into tree canopy, everything burns, mature trees die. HOT

Question 3

What are surface fires?

Answer 3

Fire on ground surface, burns leaf litter, grass, many mature trees survive. COOL

Question 4

What are ground fires?

Answer 4

Organic matter smoulders underground, slowly over a long period.

Question 5

What fires have the highest fuel consumption?

Answer 5

Crown fires. e.g. boreal

Question 6

What fires have the greatest frequency and burned area?

Answer 6

Surface fires. e.g. savanna

Question 7

What is the pyrome of savannas?

Answer 7

FIL: frequent, intense, large
FCS: frequent, cool, small

Question 8

What is the pyrome of boreal forests?

Answer 8

RIL: rare, intense, large
RCS: rare, cool, small

Question 9

What is the pyrome of agriculture / deforestation?

Answer 9

ICS: intermediate, cool, small

Question 10

What are the three plant flammability strateigies?

Answer 10

• Non flammable: thick insulating bark, protects vascular cambium
• Fast flammable: ignite easily, burn wuickly, low heat release, little damage to meristems, sprouting regeneration quickly
• Hot flammable: fine, dense biomass burns slowly, high heat release. Seeding regeneration.

Question 11

What are some plant regeneration strategies?

Answer 11

• Refractory seeds / seeders. (seed release or germination triggered by fire)
• Sprouters (from below ground stores)
• Epicormic buds (grow dormant below the bark, sprout from the crown)

Question 12

What are savanna ecosystems like in regards to fire?

Answer 12

Open woody plant cover, C4 grass.
Fast flammable grasses, non-flammable trees.
Sprouting strategy in response to fire.

Question 13

What are Mediterranean ecosystems like in regards to fire?

Answer 13

Crown fires, with lots of regeneration strategies.
- Hot flammable / seeders and non flammable / sprouters

Question 14

What are temperate forest ecosystems like in regards to fire?

Answer 14

Surface fires, because of lots of litter fuel (bark and cones)
However, fire suppression causes litter accumulation and stops trees establishing, greater risk of crown fires.

Question 15

What is the Eurasia flammability strategy?
What type of fires are usually here?

Answer 15

Non flammable trees, moist needles, self pruning branches, thick bark.
e.g. Siberian Larch, Scots Pine.
Low intensity surface fires.

Question 16

What is the North America flammability strategy?
What type of fires are usually here?

Answer 16

Hot flammable trees, branches close to ground, flammable needles, thin bark.
e.g. Black Spruce, Jack Pine
Intense Crown fires.