Post on 06-Jan-2016
description
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.