Transcript Ecosystems, Biomes, Succession 2015

Ecosystems, Biomes &
Succession
Terrestrial & Aquatic
2015
ECOLOGY
• The study of how
organisms interact
with one another
and with their
nonliving
environment.
Figure 3-2
Important Ecological Terms
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Organism
Cell
Eukaryote
Prokaryote
Species
Asexual Reproduction
Sexual Reproduction
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Organisms and Species
Organisms
Populations
Communities
Ecosystems
Biomes
Biosphere
Figure 3-3
Other animals
281,000
Known species
1,412,000
Insects
751,000
Fungi
69,000
Prokaryotes
4,800
Plants
248,400
Protists
57,700
Fig. 3-3, p. 52
BIOMES:
CLIMATE AND LIFE ON LAND
• Biomes – large terrestrial regions
characterized by similar climate, soil, plants,
and animals.
• Temperature
• Precipitation
• Latitude vs. altitude
BIOMES:
CLIMATE AND LIFE ON LAND
Figure 5-9
BIOMES:
CLIMATE AND LIFE ON LAND
• The major factors determining Biome type
are precipitation and temperature.
Figure 5-10
BIOMES:
CLIMATE AND LIFE ON LAND
• Parallel changes occur in vegetation type
occur when we travel from the equator to the
poles or from lowlands to mountaintops.
Figure 5-11
DESERT BIOMES
• 30% of Earth’s land
• Evaporation exceeds precipitation.
• Little vegetation.
– Found in tropical (Sahara), temperate
(Mojave) and cold regions (Gobi).
• Succulent plants
• Deep vs. widespread roots
• Some plants secrete toxins into soil
(sagebrush)
• Small animals
DESERT BIOMES
• Tropical,
temperate
and cold
deserts.
Figure 5-12
GRASSLANDS AND
CHAPARRAL BIOMES
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Tropical grasslands (savannas)
Temperate grasslands (prairies)
Chaparral (Mediterranean, S. Cal)
Wet/dry season
Many are fire-maintained (many plants
contain oils)
GRASSLANDS AND CHAPARRAL
BIOMES
• Most grasslands
have alkaline
soil (pH of ?)
• Temperate
grasslands have
nutrient-rich soil
Figure 5-14
Polar Grasslands
• Tundra - covered
with ice and snow
except during a brief
summer
(permafrost)
• Seasonal wetlands
• Lots of migratory
animals &
mosquitoes
Figure 5-17
Chaparral
• Moderate
climate
• Dense thickets
of spiny shrubs
• Subject to
periodic fires
Figure 5-18
FOREST BIOMES
• Tropical rainforest
• Tropical deciduous
forest
• Temperate
deciduous forest
• Temperate rain
forest
• Coniferous forest
(boreal, taiga).
Figure 5-19
Tropical Rain Forest
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Heavy rainfall
High biodiversity
Broadleaf evergreens
Nutrient-poor soil
High decomposition
rate
• Greatest concentration
of nutrients in
vegetation
Figure 5-20
Temperate Deciduous Forest
• Most of the trees
survive winter by
dropping their
leaves, which
decay and
produce a
nutrient-rich soil
• Moderate rainfall
Figure 5-22
Evergreen Coniferous Forests
• Mostly cone-bearing
evergreen trees - keep
their needles yearround
• Insulating factor helps the trees survive
long and cold winters
• Cone-shape helps
shed snow
• Acidic soil
Figure 5-23
Temperate Rain Forests
• Coastal areas (Calif., Oregon, Washington) - huge conebearing evergreen trees such as redwoods and Douglas fir
• Cool moist environment
• Soil may be more acidic so pH is ?
Figure 5-24
MOUNTAIN BIOMES
• High-elevation
islands of
biodiversity
• Snow-covered
peaks - reflect solar
radiation
• Release water to
lower-elevation
streams and
ecosystems.
Figure 5-25
Natural Capital Degradation
Desert
Large desert cities
Soil destruction by off-road
vehicles
Soil salinization from
irrigation
Depletion of groundwater
Land disturbance and
pollution from mineral
extraction
Fig. 5-26, p. 123
Natural Capital Degradation
Grasslands
Conversion to cropland
Release of CO2 to atmosphere
from grassland burning
Overgrazing by livestock
Oil production and off-road
vehicles in arctic tundra
Fig. 5-27, p. 123
Natural Capital Degradation
Forests
Clearing for agriculture, livestock
grazing, timber, and urban
development
Conversion of diverse forests to tree
plantations
Damage from off-road vehicles
Pollution of forest streams
Fig. 5-28, p. 124
Natural Capital Degradation
Mountains
Agriculture
Timber extraction
Mineral extraction
Hydroelectric dams and
reservoirs
Increasing tourism
Urban air pollution
Increased ultraviolet radiation
from ozone depletion
Soil damage from off-road
vehicles
Fig. 5-29, p. 124
CLIMATE: A BRIEF
INTRODUCTION
• Weather
• Climate - Latitude and elevation help
determine climate.
• Warm front
• Cold front
• High pressure
• Low pressure
• Adiabatic cooling
FRONTS
 the movement of warm and cold masses of air creates
the weather, and when the two clash, it often rains.
 A warm front is defined as the transition zone where a
warm air mass is replacing a cold air mass. Warm fronts
generally move from southwest to northeast and the air
behind a warm front is warmer and more moist than the
air ahead of it. When a warm front passes through, the
air becomes noticeably warmer and more humid than it
was before.
FRONTS
• A cold front is defined as the transition
zone where a cold air mass is replacing a
warmer air mass. Cold fronts generally
move from northwest to southeast. The air
behind a cold front is noticeably colder and
drier than the air ahead of it. When a cold
front passes through, temperatures can
drop more than 15 degrees within the first
hour.
FRONTS
PRESSURE SYSTEMS
• The air associated with a high pressure system sinks
down from above and warms as it does so and is very
stable.
• A high pressure system (anticyclone), is a system of
closed isobars surrounding a region of relatively high
pressure. When compared with low pressure systems,
highs tend to cover a greater area, move more slowly
and have a longer life.
• When the high pressure system is located over land the
weather will be typically dry and free of cloud.
PRESSURE SYSTEMS
• A low pressure system (cyclone) develops
where relatively warm air ascends from the
Earth's surface. These are systems of closed
isobars surrounding a region of relatively low
pressure.
• As the rising air cools, clouds will begin to form.
The instability of the air will produce quite large
vertical development of cumuliform clouds with
associated rain showers (such as cumulonimbus
cloud).
Adiabatic Cooling
• Adiabatic cooling deals with
the cooling of parcels of air
as they rise, or are forced
up, through the atmosphere.
Adiabatic cooling
Earth’s Current Climate Zones
Figure 5-2
Solar Energy and Global Air
Circulation: Distributing Heat
Climate is affected by:
• 1) Uneven heating of
the earth’s surface
• 2) Seasonal changes
in temperature and
precipitation
• 3) Earth’s rotation
• 4) Unique properties
of air & water
Diagram
Figure 5-3
Coriolis Effect
• Deflection of air
due to the rotation
of the earth &
friction between
air & Earth – less
effect near the
equator (fewer
hurricanes within
5 degrees)
Coriolis Effect
Trade Winds
Figure 5-4
Convection Currents
• Drive day-today weather
patterns
• Rainshadow
Effect
Figure 5-5
Convection Cells
• Distribute heat &
moisture
• 6 Vertical currents at
different latitudes :
• Hadley Cell – 0 – 30
- tradewinds
• Ferrel Cell – 30-60westerlies
• Polar Cell- 60 – 90 easterlies
Figure 5-6
El Nino/ENSO
• Equatorial winds weaken along
Eastern Pacific
• Surface water warms
• No upwelling
• Increased flooding in e. Pacific
• Drier western Pacific
• Fewer Atlantic hurricanes
World Map
La Nina
• Exaggerated normal pattern
• Cooler water than normal
along eastern Pacific
• Drier eastern Pacific
• Flooding along western
Pacific
• More Atlantic hurricanes
Topography and Local Climate:
Land Matters
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Rain Shadow effect
Microclimates (forests, cities)
Sea breezes
Land breezes
Figure 5-8