Terrestrial Biomes IB Syllabus: 2.4.1-2.4.2 AP Syllabus Ch 6 Video – planet Earth – pole to pole
Dec 17, 2015
Terrestrial Biomes
IB Syllabus: 2.4.1-2.4.2AP Syllabus
Ch 6Video – planet Earth – pole to pole
Syllabus Statements
• 2.4.1: Define the term Biome
• 2.4.2: Explain the distribution, structure and relative productivity of tropical rainforests, deserts, tundra and any other biome
vocabulary
• Biome
• Latitude
What is a biome?• World climate is variable
– Differences in temperature and precipitation– Different climates Different communities
• Biomes = Regions of the earth characterized by specific climates and community types
• Remember they cross national boundaries• Real biomes do not have sharply defined
boundaries. Ecotones = Transitional zones• Biomes not uniform, instead a mosiac of
patches– Vary in microclimate, soil types, disturbances
Dry woodlands and shrublands (chaparral)
Temperate grassland
Temperate deciduous forest
Boreal forest (taiga), evergreen coniferousforest (e.g., montane coniferous forest)
Arctic tundra (polar grasslands)
Tropical savanna,thorn forest
Tropical scrub forest
Tropical deciduous forest
Tropical rain forest,tropical evergreen forest
Desert
Ice
Mountains(complex zonation)
Semidesert,arid grassland
Tropic ofCapricorn
Equator
Tropic ofCancer
Major Terrestrial Biomes
1. Desert
2. Tundra
3. Forests1. Tropical Rainforest, Tropical deciduous forest
2. Temperate Rainforest, Temperate deciduous
3. Tiaga (Boreal)
4. Grasslands
5. Scrublands
6. Mountains
For each Biome you should comment in the distribution, climate (read
climatograms), structure, relative productivity and limiting factors
MountainIce and snow
Altitude
Tundra (herbs,lichens, mosses)
ConiferousForest
Tropical Forest
DeciduousForest
Tropical Forest
DeciduousForest
ConiferousForest
Tundra (herbs,lichens, mosses)
Polar iceand snow
Latitude
Main Biome Effects
Climate and vegetation vary in a predictable fashion with changes in Altitude and Latitude
Vegetation changes
• Plants in cold regions have traits to limit heat & water loss– Winter dormancy (drop leaves), smaller size,
evergreens have needles
• Plants in dry areas must lose heat and conserve water– No leaves, water storage, nocturnal activity
• Plants in rainforests must get light and remove water– Broad leaves, drip tips, radiate heat
mft
10
50
20
30100
Tropicalrain forest
Coniferousforest
Deciduousforest
Thornforest
Tall-grassprairie
Short-grassprairie
Desertscrub
Thornscrub
Comparison of types, sizes and stratification of species in different terrestrial biomes (structure)
Deserts1. Climate
• Precipitation < 25 cm / yr – scattered unevenly through year Arid
• May be Tropical, Temperate and Cold types – always extremes
• High to moderate insolation2. Distribution
• 30% of earth surface between 30 degrees north and south of the equator – Major ones Saraha (Africa), Gobi (Asia), Mojave (N. america)
3. Structure• Simple – very little vegetation • Most complex is temperate desert which has largest cacti
4. Relative Productivity• Low – limited by water availability
World Distribution of Deserts
Desert Types
• Tropical Deserts• High temp. year round• Little rain, only 1-2
months• Driest places on earth• Few plants• Hard windblown
surface: sand & rock• Middle East areas
Tropical desert(Saudi Arabia)
Desert Types
• Temperate Deserts• Day temp. high in
summer, low in winter• More precipitation• Sparse vegetation –
suculents, cacti, animals
• Southern CA (Mojave)
Temperate desert(Reno, Nevada)
Desert Types
• Cold deserts• Winters cold• Summers warm to hot• Precipitation low• Gobi desert, China
Polar desert(northwest China)
Plant Adaptations
Every drop of water counts1. Wax coated leaves limit
transpiration2. Deep roots tap
underground water3. Wide spread shallow
roots gather falling water4. Drop leaves & dormancy
in heat & dry periods5. Store biomass in seeds
Animal Adaptations
• Hiding in cool areas during day
• Thick skin• Dry feces,
concentrated urine• Water from dew & food• Dormancy in heat &
drought
Producer to primaryconsumer
Primaryto secondaryconsumer
Secondary tohigher-levelconsumer
All producers andconsumers todecomposers
Fungi
Gambel'squail
Red-tailed hawk
Collaredlizard
Jackrabbit
Yucca
Kangaroo ratKangaroo rat
AgaveAgave
RoadrunnerRoadrunner
Diamondback rattlesnakeDiamondback rattlesnakeDarklingbeetleDarklingbeetle
BacteriaBacteria
Pricklypearcactus
Pricklypearcactus
Human Impacts on Deserts
Large desert cities
Soil destruction by vehiclesand urban development
Soil salinization from irrigation
Depletion of undergroundwater supplies
Land disturbance and pollutionfrom mineral extraction
Storage of toxic and radioactiveWastes
Large arrays of solar cells andsolar collectors used to produceelectricity
Temperate Grasslands
1. Climate• Precipitation 25-45 cm / yr – enough to grow grass, erratic Semiarid• fire, drought, animals prevent tree growth• May be Tropical, Temperate• Moderate insolation
2. Distribution• 9% of earth surface Temperate Latitudes – Major onesNA tall grass
prairie, steppes, pampas, veldt• Grasslands overall up to 40% of earth’s surface
3. Structure• Simple – grasses and herbaceous plants
4. Relative Productivity• Medium to high – high turnover of grasses, rich soils
Polar Tundra Alpine Tundra Temperate Grassland Tropical Savanna
World Distribution of Grasslands
Temperate grassland(Lawrence, Kansas)
Grassland Types
• Temperate grasslands• Vast plains and rolling
hills• Summer hot & dry• Winter cold• Sparse, uneven
precipitation• Thick fertile soils
Producer to primaryconsumer
Primaryto secondaryconsumer
Secondary tohigher-levelconsumer
All producers andconsumers todecomposers
Fungi
Bacteria
Golden eagle
Prairiedog
Blue stemgrassBlue stemgrass
CoyoteCoyote
GrasshopperGrasshopper
GrasshoppersparrowGrasshoppersparrow
Pronghorn antelopePronghorn antelope
PrairieconeflowerPrairieconeflower
Grassland Types
• Tropical Grasslands• Savannas• High average temp• Moderate rainfall• Prolonged drought• Herds of herbivores
– Grazing & Browsing
• Africa, SA, Australia• Migrations in dry
season Tropical grassland (savanna)(Harare, Zimbabwe)
Herbivore coexistence
• Minimize competition by resource partitioning
• African animals differ by region & niche
1. Giraffes eat leaves from tree tops2. Elephants eat leaves and branches further
down3. Gazelles & Wildebeasts eat short grasses4. Zebras eat longer grass & stems
Dry Grassland Moist Grassland
Warthog Thompson'sgazelle
Waterbuck Grant's zebra
Beisa oryx
Topi
Cape buffalo Wildebeest
Dry Thorn Scrub Riverine Forest
Dik-dik East Africaneland
Blue duiker Greater kudu
Bushbuck
Black rhino
Giraffe
African elephant
Gerenuk
Human effects on Grasslands
Conversion of savanna and temperategrassland to cropland
Release of CO2 to atmosphere fromburning and conversion of grasslandto cropland
Overgrazing of tropical and temperategrasslands by livestock
Damage to fragile arctic tundraby oil production, air and water pollution,and vehicles
Tundra1. Climate
• Precipitation < 15 cm / yr – mostly snow & summer rain Arid
• Bitter cold -57 – 50 °C - permafrost• low insolation gives short growing season
2. Distribution• 60 – 75 °N latitude – northern North America, Asia,
Greenland• About 20% of the earth’s surface
3. Structure• Simple – low spongy mat of vegetation, lichens, mosses• Even trees are less than knee high
4. Relative Productivity• Low – limited by temperature and insolation
Tundra Distribution
Polar grassland (arctic tundra)(Fort Yukon, Alaska)
Tundra
• Treeless spongy mat of low growing plants
• Common breeding area b/c predators visible
• Organisms migratory• Cold & Windy & Dark• Ice & snow cover• Low precipitation but
poor drainage b/c Permafrost
Producer toprimaryconsumer
Primary to secondaryconsumer
Secondary tohigher-levelconsumer
All consumersand producers to decomposers
Lemming
Arcticfox
Horned lark
Mosquito
Grizzly bear
Long-tailed jaeger
Caribou
Willow ptarmiganWillow ptarmigan
Snowy owlSnowy owl
Dwarf willowDwarf willow
Mountain cranberryMountain cranberry
Moss campionMoss campion
Forest Types
• Undisturbed areas with moderate to high rainfall
• Dominated by various species of trees and other vegetation
• 3 main types of forest – Tropical, Temperate, Boreal
World Distribution of Forests
Temperate coniferous forests Temperate deciduous forests Tropical rain forests
Tropical Rainforest1. Climate
• Precipitation over 150 cm / yr – Wet – still rainy and dry seasons• Warm humid year round climate 80 °F • high insolation gives long growing season
2. Distribution• 23.5 °N to 23.5 °S latitude – Tropic of Capricorn to Cancer • About 2% of the earth’s surface• Three chunks – S. & C. America, C. Africa, SE Asia
3. Structure• Complex – stratified layers • High diversity - 50-80% of terrestrial species
4. Relative Productivity• Highest in terrestrial system – unlimited by temperature and insolation
Tropical rain forest(Manaus, Brazil)
Tropical Rainforest
• Tropical Rainforest• Broadleaved evergreen trees• High biological diversity,
Specialized niches, • Much of animal life found in
canopy layer• Stratification of life in different
tree layers increases niche partitioning
• Paradox high diversity but very poor soils
• Rapid recycling of nutrients• Little nutrients stay in soil
most taken back into plants• Dense forest limits wind
animal pollinators
Harpyeagle
Tocotoucan
Woolyopossum
Braziliantapir
Black-crownedantpitta
Shrublayer
Canopy
Emergentlayer
UnderstoryUnderstory
GroundlayerGroundlayer
0
5
10
15
20
25
30
35
40
45H
eigh
t (m
eter
s)
Producer to primaryconsumer
Primaryto secondaryconsumer
Secondary tohigher-levelconsumer
All producers andconsumers todecomposers
Fungi
Bacteria
Bromeliad
Ants
Tree frog
Green tree snake
Katydid
Climbingmonstera palm
Squirrelmonkeys
Blue andgold macaw
Harpyeagle
Ocelot
Slaty-tailedtrogon
Slaty-tailedtrogon
Diverse forests cleared
Replaced with monospecific stands – tree plantations
Songbird species often spend time in these areas
Top predators hunted out and displaced
Fragmentation of habitats
Temperate deciduous forest(Nashville, Tennessee)
Forests
• Temperate Forests• Significant seasonal
changes• Abundant precipitation
throughout year• Dominated by a few
broadleaved deciduous trees
• Simple structure• Thick layer of leaf litter• Once diverse, now
predators gone
Producer to primaryconsumer
Primaryto secondaryconsumer
Secondary tohigher-levelconsumer
All producers andconsumers todecomposers
Bacteria
Fungi
Wood frog
Racer
Shagbark hickory
White-taileddeer
White-footedmouse
White oak
Graysquirrel
Hairywoodpecker
Broad-wingedhawk
Long-tailedweaselLong-tailedweasel
May beetleMay beetle
MountainwinterberryMountainwinterberry
Metallic wood-boringbeetle and
Metallic wood- boring beetle and larvae
Polar evergreen coniferous forest (boreal forest, taiga)(Moscow, Russia)
Forests
• Boreal Forests (Tiaga)• Just below tundra• Dominated by coniferous
tree species– Withstand cold, rapid
growth in summer
• Low temperature– Low decomposition, high
soil acidity
• In summer soil is waterlogged = muskegs
Producer to primaryconsumer
Primaryto secondaryconsumer
Secondary tohigher-levelconsumer
All producers andconsumers todecomposers
Bacteria Bunchberry
Starflower
Fungi
Snowshoehare
Bebbwillow
Moose
Wolf
Balsam fir
Blue jay Greathornedowl
Greathornedowl
WhitespruceWhitespruce
Pine sawyer beetle and larvae
Pine sawyer beetle and larvae
MartenMarten
Clearing and degradation of tropicalforests for agriculture, livestock grazing,and timber harvesting
Clearing of temperate deciduousforests in Europe, Asia, andNorth America for timber, agriculture,and urban development
Clearing of evergreen coniferousforests in North America, Finland,Sweden, Canada, Siberia,and Russia
Conversion of diverse forests to lessbiodiverse tree plantations
Human Effects on Forests
Climatograms Review