Chapter 3: Forest Biomes of the World Flashcards
What are the seven forest biomes?
- Boreal; 2. Temperate broad-leaved deciduous; 3. Temperate needle-leaved evergreen; 4. Temperate mixed; 5. Temperate broad-leaved evergreen; 6. Tropical broad-leaved evergreen; 7. Tropical broad-leaved deciduous
This factor is the major control on climate at the global scale
Solar radiation
Where on the globe is the amount of solar radiation greatest?
Equator
What are the two causes for the variation in solar radiation that reaches Earth?
- The angle at which solar radiation strikes the earth’s surface 2. The length of the pathway that solar radiation must pass to reach the canopy
Is seasonal temperature variation (within a similar latitudinal zone) greater for a continental or coastal location?
Continental
For similar latitude and elevation, is the climate milder/more equitable in the Southern or Northern Hemisphere?
Southern Hemisphere
This forest biome occurs only in the Northern Hemisphere
Boreal forest
Where is the greatest single area of boreal forest?
Eurasia
What is the Average Net Primary Production for Boreal forests?
4.2 tC ha-1 yr-1
Are boreal forest soils nutrient-rich?
No
What created the parent material for the relatively young soils of the boreal forest biome?
Retreating glaciers
In the boreal forest biome, this can be less than one meter below the surface and restrict root zones and impede soil water drainage
Permafrost
Is tree species diversity poor in boreal forests?
Yes
What are two factors that cause low tree species diversity in boreal forests?
Harsh climate and recent retreat of glaciers
These play a more important role in boreal forests that in any other forest biome
Bryophytes
What are three bryophytes that are common in boreal forests?
Lichens, feathermoss, and sphagnum
Do boreal forests have low leaf area index?
Yes
What are two reasons why conifers have spiral canopies?
To shed snow and maximize light interception when the sun is low in the sky
What are two reasons for the low leaf area index (LAI) of boreal forests?
Extremely short growing season and very nutrient poor soils
What does ANPP stand for?
Aboveground net primary production
What percent of the total aboveground biomass of boreal forests do bryophytes constitute?
Less than 1%
In boreal forests, these insulate the soil, affecting the thermal regime, nutrient cycling and productivity
Bryophytes
This is an important natural disturbance in boreal forests
Fire
What three attributes of boreal forests are influenced by fire?
Species composition, nutrient availability, and forest productivity
Are boreal forests typically highly managed?
No
What are three reasons why boreal forests are one of the least managed forest biomes?
Low growth rates, extreme climate, and inaccessibility
What region has the most management of natural and plantation boreal forests?
Nordic countries (Denmark, Sweden, Finland, Norway)
These form a coarse classification system of aquatic/terrestrial ecosystems
Biomes
What are biomes typically based on?
Similarities in abiotic environment and native species
What three factors typically describe land biomes?
Geographic location, climate, and dominant plant life
What are three factors that describe biome flora?
Dominant life-form, leaf type, and plant spacing
What are three different types of dominant life-form that can describe biome flora?
Tree, shrub, grass
What are three different leaf types that can describe biome flora?
Broadleaf, needle, sclerophyll
What are two examples of types of plant spacing that can describe biome flora?
Forest and savanna
What are six factors that affect biome distribution?
Climatic, geologic, edaphic, biotic, historic, cyclic
What does edaphic refer to?
Soils
What are three ways climate can affect biome distribution?
Temperature, precipitation, humidity
What are two geologic effects on biome distribution?
Bedrock and topography
What are two edaphic effects on biome distribution?
Nutrients and pH
What are two biotic effects on biome distribution?
Competition and disease
What are two historic effects on biome distribution?
Catastrophes and faunal bridges
What are two cyclic effects on biome distribution?
El nino and fires
What is the dominant factor that affects biome distribution?
Climate
What are three ways that climate can affect flora?
Resource availability, environmental conditions, and soil formation
What are 4 examples of resources whose availability effects flora?
Water, light, nutrients, CO2
What are 4 examples of environmental condition effects on flora?
Temperature, precipitation, humidity, pH
What are six variables whose long-term trends make up a location’s climate?
Temperature; precipitation; atmospheric pressure; humidity; wind; atmospheric particles (particulates)
What are three factors that influence climate on Earth?
Distribution of solar energy; interaction of two fluid systems (atmosphere and oceans); effects of continents/land surfaces
What is the main factor that influences climate?
Solar energy distribution
What are 4 factors that make solar energy variable over the Earth’s surface?
Latitudinal effects; Planet orbit/rotation/tilt; Atmospheric effects; Surface features
Is seasonal variation more pronounced away from the Equator?
Yes
How would Earth’s axis have to be oriented relative to the orbital plane for the sun to be 90 degrees overhead at noon on the equator all year?
Perpendicular to the orbital plane
If Earth’s axis was perpendicular to the orbital plane, would day and night be equal everywhere all year long?
Yes
If Earth’s axis was perpendicular to the orbital plane, would there be seasons?
No
How much is the Earth tilted away from perpendicular?
23.5 degrees
What does this tilt drive?
The seasons
What are the five lines of latitude that track the Earth-Sun relationship?
Arctic Circle; Tropic of Cancer; Equator; Tropic of Capricorn; Antarctic Circle
What latitude is the Arctic Circle?
66.5 N
What latitude is the Antarctic Circle?
66.5 S
What latitude is the Tropic of Capricorn?
23.5 S
What latitude is the Tropic of Cancer?
23.5 N
During the Spring and Autumn Equinox, at what latitude is the Sun vertical?
Equator
During the Summer Solstice, at what latitude is the Sun vertical?
23.5 N (Tropic of Cancer)
During the Winter Solstice, at what latitude is the Sun vertical?
23.5 S (Tropic of Capricorn)
In the U.S., what happens to surface temperatures with latitude increase?
Decline
What moderates surface temperatures in the U.S.?
Coasts
Where is the highest seasonal variation in North America?
Heart of the continent
What drives atmospheric circulation?
Uneven heating
What are three influences that atmospheric circulation has on climate?
Distribution of thermal energy; Zonation of precipitation; Source of surface winds
Uneven heating causes these to form in the atmosphere
Counter-rotating convection cells
What characterizes air and surface conditions at the equator and at the 60 degree latitudes?
Rising moist air and wet surface conditions
What characterizes air and surface conditions at the poles and 30 degree latitudes?
Descending dry air and dry surface conditions
Do bands of equatorial rain move north-south with the seasons?
Yes
In these latitudes, it is wet in all seasons
Equator and 60 degree latitudes
In these latitudes, it is dry in all seasons
Poles and 30 latitudes
In these zones, rainfall is seasonal
Transitional zones
What drives oceanic circulation?
Wind causing surface water to move
What are gyres?
Large circulating ocean currents caused by wind
Where do gyres turn clockwise?
Northern Hemisphere
Where do gyres turn anticlockwise?
Southern Hemisphere
Where do gyres move warm water?
To poles
Where do gyres move cold water?
To Equator
Which sides of continents are warmer and wetter?
Eastern sides
What are three things that oceanic circulation creates?
Evaporation, clouds, and rains
Does cold air hold less water than warm air?
Yes
Which sides of continents are cooler and drier?
Western sides
In the U.S., this is a line running north-south and is the extent of eastern rainfall
Dry line
These can block rainfall, leaving a rain shadow, and also create clouds
Mountains
This funnels water into streams
Topography
These are ecosystems dominated by trees and woody vegetation
Forests
How much land area do forests occupy globally?
33%
How much leaf area do forests possess?
65%
What percentage of carbon present in all living things do forests contain?
70%
What percentage of terrestrial biodiversity do forests contain?
90%
Who created a system of forest classification in 1993?
Melillo
What three factors are forests classified by?
Climate, physiognomy, and leaf habit
What are three examples of climate forest classification?
Tropical, temperate, boreal
What is physiognomy describing?
Outward appearance of forest
What are three examples of forest classification by physiognomy?
Needleleaf, broadleaf, mixed
What are two examples of forest classification by leaf habit?
Evergreen and deciduous
What are the seven forest types that Melillo described?
Boreal; Temperate broadleaf deciduous; Temperate needleleaf evergreen; Temperate mixed; Temperate broadleaf evergreen; Tropical broadleaf evergreen; Tropical broadleaf deciduous
What are three regions where boreal forest is found?
Northern Eurasia, Canada, Alaska
What borders boreal forest to the north?
Tundra
What is boreal forest climate like?
Long frigid winters and lack of water in warm months
How many frost-free days can there be in summer in boreal forests?
<50
Are boreal forest soils typically old?
No
Are boreal forest soils typically nutrient poor?
Yes
In boreal forests, these trees acidify the soil
Conifers
In boreal forests, these can be deep and accumulate faster than they can decompose
Peat accumulations
What is peat composed of?
Partially decomposed plant material
What is boreal forest parent material usually made of?
Glacial till
In boreal forests, this restricts drainage and roots
Permafrost
This forest biome has the lowest species diversity
Boreal forest
How many species are found in boreal forests in North America?
9
This type of tree is better adapted for boreal life
Conifer
What are 3 reasons why conifers are better adapted to boreal life?
Surface area to volume ratio; Less water loss; Shape helps snow to fall off
What are 5 examples of boreal forest species?
Larch, spruce, fir, birch, aspen
What are two types of plants that live on the boreal forest floor?
Ericaceous shrubs and mosses
What does ericaceous mean?
Acid-loving
Boreal forests have this due to a short growing season
Low leaf area index
Leaf area index is an indicator of this
Productivity
Conifer shape helps them with these two functions
Intercepting low light and shedding snow
What is the Annual Net Plant Productivity of boreal forests?
4.2 tC ha-1 yr-1
Mosses do this to the soil
Insulate
This is important disturbance in boreal forests
Fire
What are two reasons why boreal forests are not as managed as others?
Geographic location and climate
Do boreal forests recover slowly after logging?
Yes
Are there many boreal forest plantations?
No
In what regions are temperate broadleaf deciduous forests located?
Eastern North America, Europe, Western China
What latitudes are temperate broadleaf deciduous forests located?
Between 30 and 50 degrees N
What are 3 characteristics of temperate broadleaf deciduous forest climates in their northern range?
Below 0 C temperatures for several months; Warm springs; Adequate rain
What are 3 characteristics of temperate broadleaf deciduous forest climates in their southern range?
Warmer; Wetter; Summer deficits can be severe
Are temperate broadleaf deciduous forest soils highly variable?
Yes
These temperate broadleaf deciduous forest soils are young and infertile
Mountain soils
These temperate broadleaf deciduous forest soils are more productive
Warm southern soils
In temperate broadleaf deciduous forests, these vary with soils, terrain, and succession
Tree species
What are 4 common tree species in temperate broadleaf deciduous forests?
Maple, hickory, oak, beech
Is tree species diversity higher in temperate broadleaf deciduous forests than in temperate needle forests?
Yes
Temperate broadleaf deciduous forest tree diversity is higher in these two regions than in Europe
North America and Asia
How long is the growing season in temperate broadleaf deciduous forests?
4-8 months
Is leaf area index in temperate broadleaf deciduous forests higher than in temperate needle evergreen forests?
Yes
What is the ANPP of temperate broadleaf deciduous forests?
6.6 tC ha-1 yr-1
In temperate broadleaf deciduous forests, these zones are very productive
Riparian zones
Is human impact on temperate broadleaf deciduous forests high?
Yes
What are two types of temperate broadleaf deciduous forest management?
Selection tree and short rotation plantations
What are two types of plantations used in temperate broadleaf deciduous forests?
Even and uneven age plantations
What are three popular temperate broadleaf deciduous plantation species?
Poplar, sweetgum, sycamore
What are three regions where temperate needleleaf evergreen forests are found?
North America, China, Europe
Temperate needleleaf evergreen forest plantations are being planted here
Southern Hemisphere
In what types of climates are temperate needleleaf evergreen forests found
Subtropical to boreal
What are 3 characteristics of climate in Pacific Northwest temperate needleleaf evergreen forests?
Cooler summers, warmer winters, summer deficits
Do temperate needleleaf evergreen forests grow on a variety of soil types?
Yes
What are two characteristics of temperate needleleaf evergreen forest soils?
Droughty and infertile
What are 5 common tree species in temperate needleleaf evergreen forests?
Fir, spruce, Douglas-fir, pine, hemlock
Which temperate needleleaf evergreen forests species are often commercially favored?
Pines
Do temperate needleleaf evergreen forests have highly variable forest type?
Yes
Is the leaf area index for temperate needleleaf evergreen forests higher than that of temperate broadleaf deciduous forests
No
Do some temperate needleleaf evergreen forests have the lowest LAIs in the world?
Yes
What is the range of ANPP for temperate needleleaf evergreen forests?
2-20 tC ha-1 yr-1
What is the average ANPP for temperate needleleaf evergreen forests?
6.6 tC
This is an important disturbance in temperate needleleaf evergreen forests
Fire
On what does temperate needleleaf evergreen forest management depend?
Productivity
Are temperate needleleaf evergreen forests among the most intensively managed?
Yes
This type of tree is planted extensively in temperate needleleaf evergreen forest plantations
Pine
Temperate needleleaf evergreen forests logging is controversial in this region
Pacific Northwest
This type of management is used increasingly in older temperate needleleaf evergreen forests
Uneven aged management
This forest biome combines broadleaf and needleleaf species
Temperate mixed forest
Where in the temperate range do temperate mixed forests occur?
Throughout temperate range
Temperate mixed forest occurrence reflects these three factors
Human land use, soils and succession
Do temperate mixed forests have a narrow range of species combinations?
No
Conifers dominate early succession in temperate mixed forests of these two U.S. regions
Southeast and Great Lakes
This biome includes sclerophyll forests and temperate rainforests
Temperate broadleaf evergreen forest
What are four regions where sclerophyll forests are found?
Mediterranean, Australia, Asia, U.S.
What are five regions where temperate rainforests are found?
Japan, Chile, New Zealand, Australia, U.S.
Are temperate broadleaf evergreen forest soils well-known?
No
Are temperate broadleaf evergreen forest soils nutrient poor?
Yes
What are two common sclerophyll forest species?
Eucalyptus and beech
What are two reasons why sclerophyllic foliage is thick and hard?
To deter herbivory and conserve water
What are two roles of toxins in temperate broadleaf evergreen leaves?
Slow decomposition and promote fires due to flammability
What is the ANPP of temperate broadleaf evergreen forests?
10.0 tC ha-1 yr-1
These temperate broadleaf evergreen forests are among the most productive in the world
Eucalyptus forests
Sclerophyll forests in this region have been exploited for millenia
Mediterranean
In this region, sclerophyll forests have been logged and planted with pine
Australia
In this country, sclerophyll forest logging has been halted
New Zealand
This is the largest forest biome in the world
Tropical broadleaf evergreen forest
What region has the largest portion of tropical broadleaf evergreen forest
Amazon basin
How much rain per year do tropical broadleaf evergreen forests receive?
> 1750mm
Are tropical broadleaf evergreen forest soils highly weathered?
Yes
What is the most limiting element in tropical broadleaf evergreen forest soils?
Phosphorus
The best tropical broadleaf evergreen forest soils are converted to this
Farming
Do tropical broadleaf evergreen forests have the highest tree diversity?
Yes
How many tree species are in the Amazon region?
> 2500
These in tropical broadleaf evergreen forests create vertical strata
Tropical broadleaf evergreen forest biomass varies with these three features
Topography, soils, age
In tropical broadleaf evergreen forests, canopy gaps add structure when these happen
Tree falls
Is tropical broadleaf evergreen forest productivity lower than temperate forest productivity?
No
What is the ANPP for tropical broadleaf evergreen forests?
8.2 tC ha-1 yr-1
These are important disturbances in tropical broadleaf evergreen forests
Cyclonic storms
Tropical broadleaf evergreen forest management is high impact due to this
High population growth
What are three contributors to tropical broadleaf evergreen forest losses
Logging, cropland, cattle
What two countries have the greatest losses of tropical broadleaf evergreen forest?
Brazil and Indonesia
What are 4 common species in tropical broadleaf evergreen forest plantations?
Eucalyptus, some softwoods, coconut, palm
This forest biome replaces tropical broadleaf evergreen forests where rain is highly seasonal
Tropical broadleaf deciduous forest
Tropical broadleaf deciduous forests often flank these sides of rainforests
North and south
Do tropical broadleaf deciduous forests have any seasonal variation of temperature?
Yes
In tropical broadleaf deciduous forests, this is highly seasonal
Rain
Are tropical broadleaf deciduous forest soils more fertile than rainforest soils?
Yes
Is tropical broadleaf deciduous forest diversity higher than that of rainforests?
No
In tropical broadleaf deciduous forests, these induce deciduous habit
Rain deficits
Are tropical broadleaf deciduous forest canopies shorter and more open than rainforest canopies?
Yes
Due to higher light penetration, tropical broadleaf deciduous forests have this
Dense shrub layer
What influences productivity in tropical broadleaf deciduous forests?
Wet season
Are there many remaining tropical broadleaf deciduous forests remaining?
No
Is tropical broadleaf deciduous forest deforestation rate higher than that of rainforest deforestation?
Yes
What are two common uses of tropical broadleaf deciduous forest land?
Ranching and crops
What are two effects of tropical broadleaf deciduous rainforest deforestation?
Erosion and soil degradation
