Download Unit 4: Terrestrial ecosystems and resources

November 07, 2014
Unit 4: Terrestrial ecosystems and resources
• Chapter 5: Climate and terrestrial biodiversity
> Climate
> Terrestrial Ecosystems
• Chapter 10: Sustaining biodiversity (ecosystem
approach)
• Chapter 11: Sustaining biodiversity (species approach)
November 07, 2014
What patterns do you
see?
What affects the
distribution of various
climates?
Blue = tropical
Red/Orange = dry
Green = temperate (moist, mild winters)
Purple/blue green = continental (moist, severe
winters)
• Grey = polar
•
•
•
•
http://en.wikipedia.org/wiki/K%C3%B6ppen_climate_classification
November 07, 2014
Climate and Weather
• Climate: region's long-term weather patterns.
• Weather: short term atmospheric conditions
(temperature, precipitation, humidity, wind speed and
direction, cloud cover, pressure).
• 2 main factors characterizes different climates: average
temperature and average precipitation
November 07, 2014
Climate and Weather
• What causes different climates?
1. Latitude (distance from equator)
2. Earth's tilt
3. Global air circulation: Coriolis effect (caused by
earth's rotation), atmospheric cells, and prevailing
winds.
4. Ocean currents
5. Proximity to water
6. Topography (Mountains)
7. Elevation (height above sea level)
November 07, 2014
1. Latitude
• Latitude: Distance from the equator
> Uneven heating of earth's surface by the sun
Cold
Intermediate
temperatures
Hot
Intermediate
temperatures
Cold
http://www.zo.utexas.edu/faculty/sjasper/images/50.11.gif
http://www.wunderground.com/news/why-does-wind-blow-20131115
John Fuller: Boise State University
November 07, 2014
2. Tilt of Earth's Axis
• Seasons (tilt of earth's axis)
November 07, 2014
November 07, 2014
3. Global air circulation
• Uneven heating of earth --> Convection
• Rotation of earth on axis --> Coriolis effects
> Northern Hemisphere: Deflected to right.
> Southern Hemisphere: Deflected to left.
Convection + Coriolis
effects = Global wind
patterns that
distribute heat and
moisture (prevailing
winds)
http://serc.carleton.edu/earthlabs/climate/5.html
November 07, 2014
November 07, 2014
Global air circulation: Convection
• Convection: distribution of heat by the movement of
masses of fluids (liquid or gas)
November 07, 2014
Global air circulation: Convection
• Uneven heating of earth's surface results in three
convection cells.
• Hadley cell-explains distribution of tropical rain forests
and deserts
> Air rises at the equator (most sun)
– Air rising = low pressure
> As air rises and cools, water condenses and
precipitates (rains a lot over the equator)
> Air gets "pushed" north and south from the equator
> Cool air falls, is compressed, and warms.
– Air falling = high pressure
> Warm dry air over land = low precipitation, takes
moisture from surface --> Deserts!
November 07, 2014
Hadley cell-explains distribution of tropical rain forests and deserts
• Air rises at the equator (most sun)
– Air rising = low pressure
• As air rises and cools, water condenses and precipitates (rains a lot over
the equator)
• Air gets "pushed" north and south from the equator
• Cool air falls, is compressed, and warms.
– Air falling = high pressure
• Warm dry air over land = low precipitation, takes moisture from surface
--> Deserts!
*Air moves from
high to low
pressure
November 07, 2014
Global air circulation: Coriolis effect
• Coriolis effect: deflection of moving air masses as a
result of the rotation of earth
> Northern Hemisphere: Deflected to right.
> Southern Hemisphere: Deflected to left.
http://nsidc.org/cryosphere/arctic-meteorology/factors_affecting_climate_weather.html
http://serc.carleton.edu/earthlabs/climate/5.html
November 07, 2014
Global Air Circulation
• Convection + Coriolis effects = Global wind patterns
that distribute heat and moisture (prevailing winds)
polar easterlies
prevailing westerlies
trade winds
http://cas.umkc.edu/geosciences/env-sci/module4/weblab4.htm
*Winds are
named by their
origin
November 07, 2014
4. Ocean Currents
• Ocean currents distribute heat and nutrients
> Redistributes heat from uneven heating of the sun.
• Factors that determine currents:
> Oceans absorb heat from the air (especially in
tropic regions) and create density differences
> Location of continents
> Winds
> Earth's rotation (Coriolis effect)
• Clockwise in northern
hemisphere
• Counterclockwise in
southern hemisphere
November 07, 2014
Ocean Currents
• Surface currents
> Wind is main force
> Coriolis
> Land forms
• Deep-sea currents
> Thermohaline circulation
http://oceanexplorer.noaa.gov/facts/currents.html
November 07, 2014
5. Proximity to water
• Heat is absorbed and released more slowly by water
than by land*
• Bodies of water moderate climate.
Sea breeze
Land breeze
http://www.nc-climate.ncsu.edu/edu/k12/.breezes
November 07, 2014
6. Topography (mountains)
• Mountains interrupt the flow of prevailing surface winds.
• Windward side: Air is forced up the mountain. Air
expands, cools, and loses moisture as rain and snow.
• Leeward side: Air flows down mountain. Air sinks,
contracts, heats up, and the dry air mass draws
moisture out of plants and soil below. *Rain shadow
effect
November 07, 2014
7. Elevation
• Parallel changes in
vegetation type occur
when we travel from
the equator to the
poles, or from lowlands
to mountaintops.
• You can find extremely
cold climates near the
equator at high
altitudes (Ex: Andes
mountains)
http://www.zo.utexas.edu/faculty/sjasper/images/f37.14.jpg
November 07, 2014
November 07, 2014
Other factors
• Monsoons: continents near warm oceans experience
heavy rains called monsoons. Intense heating of land
during summer creates low pressure air masses ->
draws moisture from ocean -> leads to heavy rainfall.
• Microclimates
> Concrete/asphalt absorb and hold more heat.
Human impact (vehicles, appliance use) release
lots of heat and pollutants.
> Results in higher temperatures, lower wind
speeds (buildings block winds)
• Greenhouse effect
November 07, 2014
Biomes
• The distribution of organisms is determined largely by
climate.
• Different climates support different communities of
organisms.
November 07, 2014
Biomes
• Biomes are large terrestrial regions characterized by
similar climate, soil, plants, and animals.
• Biomes are not uniform. Just a general characterization
of an area.
List of biomes:
1.
Desert (Tropical, temperate, cold)
2.
Grasslands
>
Tropical grasslands (savannas)
>
Temperate grasslands
>
Polar grasslands (tundra)
>
Chapparral
3.
Forests
>
Tropical rain forest
>
Temperate deciduous forests
>
Evergreen coniferous forests
>
Temperate rain forest
4.
Mountain biomes
5.
Polar Ice
November 07, 2014
Desert
•
•
•
•
Evaporation > Precipitation
30% land surface
Interior of continents, rain shadow
Hot day, cold night
http://environment.nationalgeographic.com/environment/habitats/desert-map/
November 07, 2014
Desert
• Tropical desert: Hot, dry. Few plants. Rocks and sand
• Temperate desert: High temperature in summer, low
in winter. More precipitation. Drought resistant shrubs
and cacti/succulents.
• Cold desert: Cold winters, low precipitation, sparse
vegetation
November 07, 2014
Desert
• Organisms: beat the heat, every drop of water counts
> Plants (stomata, water storage, leaves, root
systems, life cycle)
> Animals (small, burrow, thick skin, dry feces/urine)
> Fragile ecosystems
– Slow plant growth (LF=water)
– Low species diversity
– Low nutrient cycling (low bacterial activity
http://wc.pima.edu/~bfiero/tucsonecology/adaptations/adaptations_home.htm
http://www.desertusa.com/survive.html
http://wc.pima.edu/~bfiero/tucsonecology/adaptations/adaptations_home.htm
November 07, 2014
Grasslands and Chaparral
• Interiors of continents
• too moist for deserts, too dry for forests
• Characteristics:
> seasonal drought
> grazing
> occasional fires
> low average precipitation
> range in average temperatures
Three types:
• Tropical
• Temperate
• Polar
http://environment.nationalgeographic.com/environment/habitats/grassland-map/
November 07, 2014
Grasslands
Tropical Grasslands/Savannas
• Warm temp year-round
• alternating dry/wet seasons
• Drought + grazing + fire inhibit growth of trees/bushes
• Animals: farsighted, fast, stealthy.
> Grazing and browsing hoofed animals
> Migration to seasonal watering holes
> Specialized eating
• Plants: survive drought
• Human impact: rangeland, overgrazing, trees for
firewood --> desert
http://www.mnh.si.edu/mammals/pages/where/africa/waterhole.htm
November 07, 2014
Grasslands
Temperate grasslands
• Cold winter, hot dry summer
• Sparse precipitation
• Drought + fire + grazing + winds prevent trees and
bushes
• Fertile soil due to decomposition of grasses + root
systems
• Tall v. short grass
• Human impact: raise crops, raise cattle, build towns/
cities
November 07, 2014
Grasslands
Polar grasslands/Arctic tundra ("marshy plain")
• Low precipitation, mostly snow
• Grasses, mosses, lichen, dwarf shrubs --> spongy mat
• Growth in "summer" 6-8 weeks (fragile biome)
• Permafrost: frozen soil
> Prevents melted snow/ice from soaking into
ground and forms seasonal wetlands, lakes,
marshes, bogs, ponds
• Organisms: insects, migratory birds, *need to survive
cold
• Human impact: oil drilling, mines, military bases
http://www.ucmp.berkeley.edu/exhibits/biomes/tundra.php
November 07, 2014
Chaparral
• Borders deserts, coastal
• Longer, rainy winters, foggy
• Vegetation: low-growing evergreen shrubs, small
trees, leaves that reduce evaporation
• Dry summers lead to fires!
> Seeds sprout
> Release nutrients
November 07, 2014
Forest Biomes
• Lots of precipitation to support trees
• Forest = trees + other vegetation
• 3 types
> Tropical
> Temperate
> Boreal (polar)
November 07, 2014
Forest
Tropical rain forest
• Extremely diverse ecosystem
• Plants: broadleaf evergreen, huge trees (buttresses),
dense canopy, vines *NPP
http://www.blueplanetbiomes.org/rainforest.htm
http://www.ecolibrary.org/page/DP9018
November 07, 2014
Forest
Tropical rain forest
• Stratification of specialized plants and animal niches
> Plants at bottom have little sunlight--huge leaves
• Lots of resources = lots of specialized species
• Adaptation for pollination (no wind)
• Acidic, low nutrient soil--nutrients stored in biomass
(quick recycling), not soil.
• Human impact: logging, crops, grazing, minerals
• Tropical dry forest
http://rainforest-australia.com/Pollination_and_flowers.htm
November 07, 2014
Tropical grassland v. Tropical forest
Think Lion King
http://scratchdjs.blogspot.com/
http://www.collegefashion.net/inspiration/fashion-inspiration-walt-disneys-the-lion-king/
November 07, 2014
Forest
Temperate deciduous forests
• moderate average temperature, change with seasons
• long warm summer, cold winters, abundant
precipitation
• vegetation: broadleaf deciduous trees, more plant life at
ground level, leaf litter
• animals: predators, deer, small mammals
• Human impact: fragmentation or loss of habitats,
industrialization and urbanization *most disturbed
November 07, 2014
Forest
Evergreen coniferous forests (boreal, taigas)
• Subarctic: long dry, cold winters, short cool summers,
large variation in sunlight
• Vegetation: coniferous evergreen trees (needle-shaped,
waxy leaves, low diversity, grow fast in summer
• Acidic, low nutrient soil
• Animals: bears, wolves, moose, lynx, many burrowing
rodent species
• Muskegs (acidic bogs)
November 07, 2014
Forest
Temperate rain forest (coastal coniferous forest)
• Rain and moisture from ocean fog
• Moderate temperatures
• Evergreens, ferns, mosses
November 07, 2014
Mountain Biomes
• Dramatic changes in altitude, climate, soil, and
vegetation
• Erosion (slopes) when vegetation removed by natural
disturbance or human
• Islands of biodiversity
> Forests, endemic species, sanctuaries for animals
(people tend to not build on mountains)
• Regulate climate: glacial ice (freshwater), ice/snow
reflect solar radiation, gradually release melting ice,
snow, and water
November 07, 2014
Human Impact
Humans use, waste, or destroy 10-55% of NPP
November 07, 2014
November 07, 2014