Transcript Biomes - PBworks

Biomes
Chapter 4
Biomes
• Large
terrestrial
regions with
similar climate:
• Autotrophs?
• Heterotrophs?
Climatogram - Climate Diagrams
Human Use of Biomes
• Warm Temp.; Abundant rain
– Allows for:
• Warm Temp.; Less rain
– Allows for:
• Colder Temp
– Allows for:
Latitude and Elevation
Elevation
Mountain ice and snow
Tundra (herbs, lichens, mosses)
Coniferous Forest
Deciduous Forest
Latitude
Tropical Forest
Tropical
Forest
Deciduous
Forest
Coniferous Tundra
Forest
Polar ice
and
snow
Latitude is distance from equator.
Elevation is altitude.
Fig. 7-9, p. 147
Three Types of Deserts
• Deserts in general:
• Tropical deserts
– Hot and dry most of the year.
– Mostly sand
– Lots of dust storms
• Temperate deserts
– Hot daytime temperature; Low temps at night.
– More precipitation than tropical deserts.
• Cold deserts
– Bitter cold winters and warmer summers
– Little precipitation – in form of snow
30C=86F
20C=68F
10C=50F
0C=32F
-10C=14F
-20C=-4F
-30C=-22F
-40C=-40F
Stepped Art
Fig. 7-11, p. 149
What Are The Plant Adaptations For The Desert?
The stem stores all of its water keeping the plant alive until the
next rain.
The stem is green - Photosynthesis occurs here.
Cactus
Many cacti have thorns to keep them safe
from many animal predators.
The white hairy
surface reflects some
of the sun’s heat.
Transpiration occurs in
stomata of the leaves.
The waxy surface of the aloe
plant acts like a plastic wrapper,
keeping precious water inside.
Desert plant leaves have
few stomata and they
open only at night.
Old Man
Cactus
Animal Adaptations in Desert
• Humps contain fat which releases
water when burned for energy.
• Temperature changes from 96˚F to
106˚F.
• Noses trap water vapor.
• Thick coat reflects light.
• Long legs keep body away from hot
sand.
• Kidneys and intestines retain water –
urine like syrup and feces so dry they
fuel fires.
Anthropogenic Effects
Grasslands
• Mostly in interior continents.
• More moist than desert and
drier than forest.
• Seasonal drought - Leads to
fires.
• Tropical Grasslands – Savannas
– Autotrophs:
– Herbivores:
• Resource Partitioning
Temperate Grasslands - Prairies
• Bitter cold winters, hot summers.
• Autotrophs:
• Hetertrophs:
Cold Grasslands - Tundra
•
•
•
•
Frigid winds, ice, snow – permafrost
Little precipitation
Autotrophs
Heterotrophs
30C=86F
20C=68F
10C=50F
0C=32F
-10C=14F
-20C=-4F
-30C=-22F
-40C=-40F
Fig. 7-12, p. 151
Anthropogenic Effects
• Tundra
– Global warming causing the
permafrost to melt in some areas.
• Prairies
– Cultivation for crops removes the
tangled network of roots and the
topsoil is subject to severe wind
erosion.
• Savannas
– Habitat loss due to increase in
population.
Temperate Shrubland
• Chaparral
– Costal areas bordering on the deserts.
– More rainfall due to closeness to the sea.
• Near the sea: nice climate: fires and mud slides
• Plants
– Low growing evergreen shrubs, small trees.
– Soil thin and not very fertile.
• Prone to fires in the dry season
– Chaparral is maintained by fires.
– Vegetation has fire resistant roots and seeds that
sprout only after a hot fire.
Chaparral
Fig. 7-14, p. 152
Three Major Types of Forests
• Dominated by trees
• Tropical
• Temperate
• Cold.
Tropical Rain Forest
• Broadleaf evergreen plants.
• Keep leaves year round.
• Incredible biodiversity 50% of plant
and animal species.
• Much species richness not species
evenness.
• Many plants used for medicines.
Layers of Rainforest
Epiphytes
• Epiphytes are plants
that live on the
surface of other
plants, especially the
trunk and branches.
• They grow on trees to
take advantage of the
sunlight in the canopy.
• Most are orchids,
bromeliads, and ferns.
Fig. 7-17, p. 156
Temperate Forest
• Long warm summers; cold but not severe winters.
• Broadleaf deciduous trees drop their leaves in
winter and become dormant.
– Leaves form layer of decaying leaf litter which stores
nutrients in soil.
• Much of these areas have been cleared for crops
and urban areas.
• Most large mammals have lost their habitats.
– Deer, small mammals, birds.
Evergreen Forest
• Called the Tiaga, Boreal Forest
• Long very cold winters; short summers cool to
warm
• Coniferous trees – cone bearing
– Needles instead of leaves.
– Needles are wax covered and hang down.
• Decomposition slow due to cold temperatures
and waxy covering of needles.
Fig. 7-15, p. 154
Anthropogenic Effects
• Deforestation – for the purpose of
crops BUT:
• Decomposition very fast due:
decomposers.
• Soil is nutrient poor.
• Even though the trees are tall they do
not have extensive roots but rather
buttresses for support.
Mountains
• Steep high lands covering ¼ of earth’s surface.
• 18% of population live on mountain ranges or
edges.
• 59% people depend on mountains for water.
• Soil is easily eroded by natural or man-made
disasters including mining.
Fig. 7-19, p. 157
Ecological Role of Mountains
• Contain the majority of the world’s forests.
• Habitats for endemic species.
• Help regulate the earth’s climate.
– Ice and snow high albedo.
– Melting of glaciers exposes dark rocks that absorb
heat.
• Can affect sea levels – melting glaciers.
• Major storehouses of water
– Role in hydrologic cycle