Transcript Chapter 5 - Fulton County Schools

Climate and Terrestrial Biodiversity
Hoh Rainforest (140 – 170 inches rainfall per year)
CLIMATE: A BRIEF
INTRODUCTION
• Weather is a local area’s short-term physical
conditions such as temperature and
precipitation.
• Climate is a region’s average weather
conditions over a long time.
– Latitude and elevation help determine climate.
Solar Energy and Global Air
Circulation: Distributing Heat
• Global air
circulation is
affected by the
uneven heating of
the earth’s surface
by solar energy,
seasonal changes
in temperature and
precipitation.
Ocean Currents:
Distributing Heat and Nutrients
• Ocean currents influence climate by
distributing heat from place to place and
mixing and distributing nutrients.
Effects of Global Warming
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Alter precipitation patterns
Shift areas we can grow crops
Raise average sea levels
Change areas where some types of
plants and animals can live
Topography and Local Climate:
Land Matters
• Interactions between land and oceans and
disruptions of airflows by mountains and
cities affect local climates.
BIOMES:
CLIMATE AND LIFE ON LAND
• Different climates lead to different
communities of organisms, especially
vegetation.
– Biomes – large terrestrial regions characterized
by similar climate, soil, plants, and animals.
– Each biome contains many ecosystems whose
communities have adapted to differences in
climate, soil, and other environmental factors.
Tropic of
Cancer
Equator
High mountains
Polar ice
Polar grassland (arctic
tundra)
Temperate grassland
Tropical grassland
(savanna)
Chaparral
Coniferous forest
Temperate deciduous forest
Tropical forest
Desert
Tropic of
Capricorn
BIOMES:
CLIMATE AND LIFE ON LAND
• Biome type is determined by precipitation,
temperature and soil type
Elevation Mountain
ice and snow
Tundra
(herbs,
lichens,
mosses)
Coniferous
Forest
Latitude
Deciduous
Forest
Tropical
Forest
Tropical
Forest
Deciduous Coniferous Tundra
(herbs,
Forest
Forest
lichens,
mosses)
Polar
ice
and
snow
DESERT BIOMES
• Deserts are areas where evaporation
exceeds precipitation.
• Deserts have little precipitation and little
vegetation.
– Found in tropical, temperate and polar
regions.
• Desert plants have adaptations that
help them stay cool and get enough
water.
DESERT BIOMES
• Variations in
annual
temperature (red)
and precipitation
(blue) in tropical,
temperate and
cold deserts.
Desert Plant Adaptations
• Drop their leaves during hot and dry spells to
survive dormant state
• Succulent plants – fleshy plants store water
• Some have deep roots to tap into
groundwater
• Some have widely spread, shallow roots to
collect water during brief rain showers
• Spines to guard against predators
• Wax coated leaves to reduce water loss
• Grasses and wildflowers store their biomass
in seeds
Desert Animal Adaptations
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Small
Hide in burrows during day and hunt at night
Dormant during periods of extreme heat and drought
Insects and reptiles thick outer coverings
Insects and reptiles feces is dry and a dried concentrate of
urine to minimize water loss
• Get water from dew
Dry urine
Dry feces
Saguaro (“sah-WAH-ro”)cactus
• No leaves
• Store water and synthesize food in their
expandable fleshy tissue
• Reduce water loss by opening their stomata
only at night to take up CO2
-Grow up to 50 feet tall
-Live up to 200 years
-Grow a few inches a year
-Branches around 50 years
Why are desert ecosystems
fragile?
 Soils take a long time to recover
 Slow plant growth
 Low species diversity
 Slow nutrient cycling
 Lack of water
GRASSLANDS AND CHAPARRAL
BIOMES
• Variations in
annual
temperature
(red) and
precipitation
(blue).
GRASSLANDS
• Grasslands occur in
areas too moist for
desert and too dry
for forests.
Savanna Grasslands
• Scattered clumps of trees
• Animals farsighted, swift,
stealthy
• Large herds of hoofed animals
• Seasonal droughts
• Occasional fires
Temperate Grasslands
• The cold winters and
hot dry summers
have deep and fertile
soil that make them
ideal for growing
crops and grazing
cattle.
Temperate grassland
Chaparral
• Chaparral has a
moderate
climate but its
dense thickets of
spiny shrubs are
subject to
periodic fires.
Chaparral
Arctic tundra
Why is the tundra a fragile
biome?
 Short growing season
 Soil and vegetation recovers slowly
 Human activities leave scars that persist
for centuries
FOREST BIOMES
• Variations in annual
temperature (red)
and precipitation
(blue) in tropical,
temperate, and
polar forests.
Bromeliad
buttress
Rafflesia – world’s largest
flower which smells like
rotting flesh
Dense vegetation = little wind
Rainforest depends on others to
spread seeds and pollen
Tropical Rain Forest
Stratification of
specialized plant
and animal niches
• Filling such niches enables species to avoid or
minimize competition and coexist
Temperate Rain Forests
• Coastal areas support huge cone-bearing
evergreen trees such as redwoods and
Douglas fir in a cool moist environment.
Temperate deciduous forest
Taiga (Boreal) Forest
Long winters
Coniferous trees
Low plant diversity
High soil acidity
Soil nutrient poor
Taiga
MOUNTAIN BIOMES
• High-elevation
islands of
biodiversity
• Often have snowcovered peaks that
reflect solar
radiation and
gradually release
water to lowerelevation streams
and ecosystems.
Tree line
Ecological Role of Mountains
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Contain majority of world’s forest
Often habitats for endemic species
Sanctuaries for animal species driven from lowland
Help regulate earth’s climate
About 75% of world’s freshwater stored as glacial ice
Critical role in hydrologic cycle
Human impact tropical
rainforest
Human impact on deserts
Human impact on grasslands
Human impact on forests
Human impact on mountains
The End