Boreal Forest and Fire

  sq. mi. sq. km.

Boreal Forests

6.4 16.6

Other Forests

12.8 33.2

Nearly continuous belt of coniferous trees across North America and Eurasia

Map source, Hare and Ritchie (1972).

•Long, severe winters

•Short summers

•Low summer precipitation

Climate associated with the Boreal Forest

Overlying formerly glaciated areas and areas of patchy permafrost

Soils are podzols

Soils are very acidic and often waterlogged

Soils associated with the Boreal Forest

•Vegetation is a mosaic of successional and subclimax plant communities

Black and white spruce are characteristic species along with jack pine and balsam fir

Successional species include alder (Alnus), birch (Betula), and aspen (Populus).

Black Spruce (Picea

mariana)

Jack Pine(Pinus banksiana)

Lots of water bodies

Muskegs

Patterns of annual area burned in the North American boreal forest illustrating a continuous rise in fire activity since the early 1970s (Kasischke 1999)

Boreal Fire Locations between 1980 - 1994

Fire Effects on Wildlife Populations

CARBON CYCLE

Fire influences carbon cycling both directly and indirectly in the boreal forest

Direct: consumption of trees, understory vegetation, lichen, moss, litter, organic soil

RESULT: instant flux of carbon to the atmosphere

Indirect: 1) change in albedo (surface reflectivity

Indirect: 2) vegetation succession

RESULT: slow flux of carbon to the atmosphere

RESULT: CO2 sequestration during regrowth

Fifty years of soil temperature data at a boreal forest site near Fairbanks, Alaska indicate 2 - 5 oC warming, now approaching thaw. This warming will likely effect fire regimes and the occurrence of permafrost, which in turn will effect carbon storage. Data of Vladimir Romanovsky, 1999.