BIO 176: Exam 2 - Boreal Forest
Soils
Completely glaciated 10000 ybp Moist ,acidic, low nutrient soils Drainage varies widely, from saturated to well-drained
Black spruce communities
In colder, wetter sites. Moss carpet ground cover common Less diverse
The boreal forest is characterized by all of the following except: -- low diversity -- sharp transitions between habitat types -- dominated by conifers, mosses and lichens. -- includes different habitat types -- the boreal forest is characterized by cold temperatures
sharp transitions between habitat types
Boreal forests are how much more or less productive than temperate deciduous forests? [Use a previous chapter to find this answer.] -- 1/4 -- 1/2 -- 1 -- 1 1/2
1/2
Select the incorrect statement about boreal forests. -- Black spruce communities often have carpets of moss over large areas of their understories -- White spruce tend to dominate drier sites. -- White spruce communities tend to have more shrubs than black spruce communities -- Black spruce communities tend to have higher diversity
Black spruce communities tend to have higher diversity
Closed forests
Black spruce, white spruce, balsam fir (Picea mariana, Picea glauca, Abies balsamea) Mosses Shrubs and perennial herbs
Vegetation overall characteristics
Four layers, short (< 50′) Low tree diversity; high moss diversity Spruce (White=dry sites, Black=wet sites) Seral birches and aspen
Important determinants of boreal soils include all of the following except, [Rely on your understanding of past lectures to answer this question.] -- The acidity of soils helps slow decomposition -- Build up of organic matter helps create acid soils -- High moisture helps create acid soils -- Cold temperatures slow decomposition even more than they slow plant growth -- High productivity of boreal forests helps create a build up of organic matter
High productivity of boreal forests helps create a build up of organic matter
Fauna
Lynx Snowshoe hare Connecticut Warbler Great grey owl Northern hawk owl Lincoln's sparrow White-throated sparrow Hermit thrush
Why do spruces and firs dominate the boreal forest?
Spruces and firs have specific traits that allow them to tolerate the severe conditions in the boreal forest biome: -- Embolism-resistant, andrupture-resistant tracheids (extreme low temperature) -- Long-lived leaves (low nutrient soils) -- Sunken stomates, thick bark (low precipitation or frozen soils)
White spruce communities
In warmer, drier sites Mixed shrub, herb, moss understory common More diverse
Distribution
South of the arctic tundra North of deciduous forest, central grasslands, and montane and coastal forests Spans all longitudes
Disturbances - Insect outbreaks
Spruce bark beetle and spruce budworm
The boreal forest is bounded by all of the following except: -- Tundra, to the south -- Atlantic Ocean, to the east -- Rocky Mountains (in part), to the west -- No answer text provided
Tundra, to the south
Bogs
Wetland that accumulates peat, a deposit of dead plant material—often mosses