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LECTURE PRESENTATIONS
For CAMPBELL BIOLOGY, NINTH EDITION
Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert B. Jackson
Chapter 52
An Introduction to Ecology and
the Biosphere
Lectures by
Erin Barley
Kathleen Fitzpatrick
© 2011 Pearson Education, Inc.
Overview: Discovering Ecology
• Ecology is the scientific study of the
interactions between organisms and the
environment
determine distribution of organisms and
their abundance
includes observation and experimentation
How is this different from the environment?
© 2011 Pearson Education, Inc.
Figure 52.1
Figure 52.2
Global ecology
Landscape ecology
Ecosystem ecology
Community ecology
Population ecology
Organismal ecology
Global Ecology
• The biosphere is the global ecosystem, the sum
of all the planet’s ecosystems
• Global ecology examines the influence of
energy and materials on organisms across the
biosphere
© 2011 Pearson Education, Inc.
• Landscape ecology - exchanges
of energy, materials, and
organisms across multiple
ecosystems
© 2011 Pearson Education, Inc.
Figure 52.2b
Landscape ecology
• Ecosystem ecology
emphasizes energy flow
and chemical cycling
among the various biotic
and abiotic components
© 2011 Pearson Education, Inc.
Figure 52.2c
Ecosystem ecology
• Community ecology deals
with the whole array of
interacting species in a
community
© 2011 Pearson Education, Inc.
Figure 52.2d
Community ecology
• Population ecology
focuses on factors
affecting population size
over time
© 2011 Pearson Education, Inc.
Figure 52.2e
Population ecology
• Organismal ecology includes
physiological, evolutionary, and
behavioral ecology
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Figure 52.2f
Organismal ecology
Concept 52.1:
• Climate - the long-term prevailing weather
conditions in an area: temperature, precipitation,
sunlight, wind
• Macroclimate - global, regional, and landscape
level
• Microclimate –small, area (community of
organisms underneath a fallen log)
© 2011 Pearson Education, Inc.
Global Climate Patterns
• determined by solar energy and the
planet’s movement in space
• causes temperature variations, which
drive evaporation and the circulation
of air and water
• This causes latitudinal variations in
climate
© 2011 Pearson Education, Inc.
Latitudinal Variation in Sunlight Intensity
What does this mean? Why does it happen?
© 2011 Pearson Education, Inc.
Figure 52.3a
Atmosphere
Low angle of incoming sunlight
90°N (North Pole)
60°N
30°N
23.5°N (Tropic of
Cancer
Sun overhead at equinoxes
0° (Equator)
23.5°S (Tropic of
Capricorn)
30°S
Low angle of incoming sunlight
60°S
90°S (South Pole)
Latitudinal variation in sunlight intensity
• Rising air masses release water and cause high
precipitation, especially in the tropics
• Dry, descending air masses create arid climates,
especially near 30°
• Air flowing close to Earth’s surface creates
predictable global wind patterns
• Cooling trade winds blow from east to west in the
tropics; prevailing westerlies blow from west to
east in the temperate zones
© 2011 Pearson Education, Inc.
Figure 52.3b
66.5°N (Arctic Circle)
60°N
30°N
30°N
Westerlies
Northeast trades
Ascending
moist air
releases
moisture.
0°
Southeast trades
30°S
Westerlies
Descending
dry air
absorbs
moisture.
0°
60°S
66.5°S (Antarctic Circle)
Global air circulation and precipitation patterns
Regional and Local Effects on Climate
• Climate is affected by
seasonality, large bodies of
water, and mountains
© 2011 Pearson Education, Inc.
Seasonality
• Seasonal variations of light and
temperature increase steadily toward
the poles (WHY?)
• Belts of wet and dry air straddling the
equator shift throughout the year with
the changing angle of the sun
• Changing wind patterns affect ocean
currents
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Figure 52.4
March equinox
December
solstice
Constant tilt
of 23.5°
June solstice
60°N
30°N
0° (equator)
30°S
September equinox
The trip around
• What do we mean by the equinox?
When do they occur?
• What do we mean by the solstices?
When do they occur?
Bodies of Water
• Oceans, their currents, and large
lakes moderate the climate of nearby
terrestrial environments
• The Gulf Stream carries warm water
from the equator to the North Atlantic
© 2011 Pearson Education, Inc.
Figure 52.5
Labrador Current
California Current
Gulf Stream
30°N North Pacific
Subtropical Gyre
North Atlantic
Subtropical
Gyre
Equator
Indian
Ocean
Subtropical
Gyre
Antarctic Circumpolar Current
30°S
South Pacific
Subtropical Gyre
South
Atlantic
Subtropical
Gyre
• Why is there a breeze at the ocean
shoreline?
© 2011 Pearson Education, Inc.
Figure 52.6
Leeward side
of mountains
Air flow
Mountain
range
Ocean
Mountains
• Rising air releases moisture on the windward
side of a peak and creates a “rain shadow” as it
absorbs moisture on the leeward side
• Mountains affect the amount of sunlight reaching
an area
• In the Northern Hemisphere, south-facing slopes
receive more sunlight than north-facing slopes
• Every 1,000 m increase in elevation produces a
temperature drop of approximately 6C
© 2011 Pearson Education, Inc.
Smith Rock - Oregon
Rocky Mountains
Microclimate
• fine-scale differences in the environment that
affect light and wind patterns
• characterized by differences in
– Abiotic factors, including nonliving attributes
such as temperature, light, water, and nutrients
– Biotic factors, including other organisms that
are part of an individual’s environment
© 2011 Pearson Education, Inc.
Global Climate Change
• Predictions for change can be
based on previous changes
• Glacier retreat 16,000 years ago
caused tree distribution patterns
to change
• Specie dispersal could determine
the range and climate changes
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Figure 52.7
Current
range
Predicted
range
Overlap
(a) 4.5°C warming over next
century
(b) 6.5°C warming over next
century
Figure 52.8
Sweden
Finland
Expanded range in 1997
Range in 1970
Concept 52.2:
• Biomes are major life zones characterized by
vegetation type (terrestrial biomes) or physical
environment (aquatic biomes)
• Climate is very important in determining why
terrestrial biomes are found in certain areas
© 2011 Pearson Education, Inc.
Figure 52.9
30°N
Tropic of
Cancer
Equator
Tropic of Capricorn
30°S
Tropical forest
Savanna
Desert
Chaparral
Temperate grassland
Temperate broadleaf forest
Northern coniferous forest
Tundra
High mountains
Polar ice
• A climograph plots the temperature and
precipitation in a region
• Biomes are affected not just by average
temperature and precipitation, but also by the
pattern of temperature and precipitation through
the year
© 2011 Pearson Education, Inc.
Figure 52.10
Annual mean temperature (°C)
Desert
Temperate grassland
Tropical forest
30
Temperate
broadleaf
forest
15
Northern
coniferous
forest
0
Arctic and
alpine
tundra
15
0
100
200
300
400
Annual mean precipitation (cm)
General Features of Terrestrial Biomes
• Terrestrial biomes are often named for major
physical or climatic factors and for vegetation
• Terrestrial biomes usually grade into each other,
without sharp boundaries
• The area of intergradation, called an ecotone,
may be wide or narrow
© 2011 Pearson Education, Inc.
• Vertical layering is an important feature of
terrestrial biomes, and in a forest it might consist
of an upper canopy, low-tree layer, shrub
understory, ground layer of herbaceous plants,
forest floor, and root layer
• Layering of vegetation in all biomes provides
diverse habitats for animals
• Biomes are dynamic and usually exhibit
extensive patchiness
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• Similar characteristic can arise in
distant biomes through
convergent evolution
–For example, cacti in North
America and euphorbs in
African deserts appear similar
but are from different
evolutionary lineages
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Figure 52.11
Euphorbia canariensis
Cereus peruvianus
Disturbance and Terrestrial Biomes
• Disturbance is an event that changes a
community
– frequent fires can kill woody plants and maintain
the characteristic vegetation of a savanna
– fires and outbreaks of pests create gaps in
forest that allow different species to grow
• Fire suppression has changed the vegetation of
the Great Plains
© 2011 Pearson Education, Inc.
Terrestrial Biomes
• Terrestrial biomes can be characterized by
distribution, precipitation, temperature, plants,
and animals
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Tropical Forest
• equatorial and subequatorial regions
• tropical rain forests, rainfall is relatively
constant,
• tropical dry forests precipitation is highly
seasonal
• (25–29C)
• Vertical layering
• Most diverse biome
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Figure 52.12a
A tropical rain forest in Borneo
Desert
• Deserts 30C N/S and in the interior of
continents
• < 30 cm per year
• Deserts may be hot or cold
• Plants adapted to climate (C4 and CAM)
• Many nocturnal animals
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Figure 52.12b
A desert in the southwestern
United States
Savanna
• Equatorial and subequatorial regions
• precipitation is seasonal
• warm year-round (24–29C) but more
seasonally variable than the tropics
• Fire adapted plants
• Grasses and forbs
• Zebras, lions, hyena
© 2011 Pearson Education, Inc.
Figure 52.12c
A savanna in Kenya
Chaparral
• midlatitude coastal regions on several continents
• rainy winters and dry summers
• Summer hot (30C+) while fall, winter, and spring
are cool (10–12C)
• Shrubs, grasses, herbs (fire-resistant)
• Insects and small mammals
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Figure 52.12d
An area of chaparral
in California
Temperate Grassland
• found on many continents
• Precipitation is highly seasonal
• Winters cold (often below –10C) and dry
summers hot (often near 30C) and wet
• Grasses and forbs adapted to fire and drought
• Bison and wild horses
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Figure 52.12e
Grasslands National Park,
Saskatchewan
Northern Coniferous Forest
• taiga, spans northern North America and
Eurasia and is the largest terrestrial biome on
Earth
• Precipitation varies
• Winters are cold and long while summers may
be hot (e.g., Siberia ranges from –50C to 20C)
• Pine, spruce, fir
• Cone shape protects breakage from snow
• Moose, bear, migratory birds, Siberian tigers
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Figure 52.12f
A forest in Norway
Temperate Broadleaf Forest
• midlatitudes in the Northern Hemisphere, with
smaller areas in Chile, South Africa, Australia,
and New Zealand
• Large amount of precip in all seasons
• Winters average 0C, while summers are hot
and humid (near 35C)
• Vertical layering
• Deciduous trees
• Mammals, birds, insects
© 2011 Pearson Education, Inc.
Figure 52.12g
Great Smoky Mountains
National Park in
North Carolina, in autumn
Tundra
• Arctic;
• Alpine tundra exists on high mountaintops at all
latitudes
• Precipitation is low in arctic tundra, and higher
in alpine tundra
• Winters are long and cold (below –30C) while
summers are relatively cool (less than 10C)
• Permafrost
• Reindeer, musk, oxen
• Mosses, grasses
© 2011 Pearson Education, Inc.
Figure 52.12h
Denali National Park, Alaska,
in autumn
Concept 52.3:
• largest part of the biosphere in terms of area
• They show less latitudinal variation than
terrestrial biomes
• Marine biomes have salt concentrations of
about 3%
• The largest marine biome (oceans) cover about
75% of Earth’s surface and have an enormous
impact on the biosphere
© 2011 Pearson Education, Inc.
• Freshwater biomes
have salt concentrations of less
than 0.1%
closely linked to soils and the
biotic components of the
surrounding terrestrial biome
© 2011 Pearson Education, Inc.
Figure 52.13
(b) Marine zonation
Intertidal zone
Neritic
zone
0
200 m
(a) Zonation in a lake
Littoral
zone
Limnetic
zone
Continental
shelf
Oceanic zone
Photic
zone
Pelagic
zone
Photic
zone
Benthic
zone
Benthic
zone
Pelagic
zone
Aphotic
zone
Aphotic
zone
2,000
6,000 m
Abyssal
zone
• Thermocline - temperature boundary called the
separating the warm upper layer from the cold
deeper water
• turnover – mixing of oxygenated water from
surface with nutrient rich water on the bottom of
a lake
© 2011 Pearson Education, Inc.
Figure 52.14
Winter
Spring
Summer
0°
2°
4°C
4°
Autumn
4°
22°
18°
8°
4°C
4°C
Thermocline
4°C
• Communities vary with depth, light
penetration, distance from shore, and
position in the pelagic or benthic zone
• Most occur in the relatively shallow photic
zone
• The aphotic zone in oceans is extensive,
but harbors little life
© 2011 Pearson Education, Inc.
Figure 52.15
30°N
Tropic of
Cancer
Equator
Tropic of
Capricorn
30°S
Oceanic pelagic and benthic zones
Intertidal zones
Estuaries
Coral reefs
Rivers
Lakes
Aquatic Biomes characterized
by:
physical environment
chemical environment
geological features
photosynthetic organisms
heterotrophs
© 2011 Pearson Education, Inc.
Lakes
• Oligotrophic lakes are nutrientpoor and generally oxygen-rich
• Eutrophic lakes are nutrient-rich
and often depleted of oxygen if
ice covered in winter
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• littoral zone close to shore
(shallow and well lit)
• limnetic zone – further from
shore small drifting animals called
zooplankton graze on the
phytoplankton
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Figure 52.16a
An oligotrophic lake in Grand
Teton National Park, Wyoming
A eutrophic lake in the Okavango
Delta, Botswana
Wetlands
• a habitat that is inundated by water at
least some of the time and that supports
plants adapted to water-saturated soil
• have high organic production and
decomposition and have
• low dissolved oxygen
• Wetlands can develop in shallow basins,
along flooded river banks, or on the
coasts of large lakes and seas
© 2011 Pearson Education, Inc.
• most productive biomes on Earth
• lilies, cattails, sedges, tamarack, and black
spruce
• invertebrates and birds, as well as otters, frogs,
and alligators
• Humans have destroyed up to 90% of wetlands;
wetlands purify water and reduce flooding
© 2011 Pearson Education, Inc.
Figure 52.16b
A basin wetland in the United Kingdom
Streams and Rivers
• prominent physical characteristic of is current
• Headwaters are generally cold, clear, turbulent,
swift, and oxygen rich; they are often narrow and
rocky
• Downstream waters form rivers and are
generally warmer, more turbid, and more
oxygenated; they are often wide, meandering,
and have silty bottoms
© 2011 Pearson Education, Inc.
Figure 52.16c
A headwater stream in the Great
Smoky Mountains
The Loire river (in France) far
from its headwaters
Estuaries
• transition area between river and sea
• Salinity varies with the rise and fall of the tides
• nutrient rich and highly productive
• include a complex network of tidal channels,
islands, natural levees, and mudflats
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• Saltmarsh grasses and algae are the major
producers
• An abundant supply of food attracts marine
invertebrates, fish, waterfowl, and marine
mammals
© 2011 Pearson Education, Inc.
Figure 52.16d
An estuary in the southeastern United States
Intertidal Zones
• periodically submerged and exposed by the
tides
• organisms are challenged by variations in
temperature and salinity and by the mechanical
forces of wave action
• Oxygen and nutrient levels are high
• Substrate varies from rocky to sandy
© 2011 Pearson Education, Inc.
Figure 52.16e
Rocky intertidal zone on the Oregon coast
Oceanic Pelagic Zone
• constantly mixed by wind-driven oceanic
currents
• Oxygen levels are high
• Turnover renews nutrients in the photic zones;
year-round stratification in tropical oceans leads
to lower nutrient concentrations
• 70% of Earth’s surface
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• Phytoplankton (diatoms) and
zooplankton are the dominant
organism; also found are freeswimming animals
• Zooplankton (protists, worms,
copepods, krill, jellies, and
invertebrate larvae
• squids, fishes, sea turtles, and
marine mammals
© 2011 Pearson Education, Inc.
Figure 52.16f
Open ocean off the island of Hawaii
Fringing reef
Barrier Reef
Figure 52.16g
A coral reef in the Red Sea
Marine Benthic Zone
• The marine benthic zone consists of the
seafloor below the surface waters of the coastal,
or neritic, zone and the offshore pelagic zone
• Organisms in the very deep benthic (abyssal)
zone are adapted to continuous cold and
extremely high water pressure
• Substrate is mainly soft sediments; some areas
are rocky
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• Shallow areas contain seaweeds and filamentous
algae
• Deep-sea hydrothermal vents of volcanic origin on
mid-oceanic ridges are surrounded by unique
chemoautotrophic prokaryotes, as well as
echinoderms and arthropods
• Neritic benthic communities include invertebrates
and fishes
• Overfishing and dumping of waste have depleted
fish populations
© 2011 Pearson Education, Inc.
Figure 52.16h
A deep-sea hydrothermal vent community
Behavior and Habitat Selection
• Some organisms do not occupy all of their
potential range
• Species distribution may be limited by habitat
selection behavior
© 2011 Pearson Education, Inc.
Biotic Factors
• Biotic factors that affect the distribution of
organisms may include
– Predation
– Herbivory
• For example, sea urchins can limit the
distribution of seaweeds
– Competition
© 2011 Pearson Education, Inc.
Figure 52.20
RESULTS
Seaweed cover (%)
100
80
Both limpets and urchins
removed
Sea urchin
Only urchins
removed
60
Limpet
40
Only limpets removed
Control (both urchins
and limpets present)
20
0
August
1982
February
1983
August
1983
February
1984
Abiotic Factors
• Abiotic factors affecting distribution of organisms
include
–
–
–
–
–
Temperature
Water
Sunlight
Wind
Rocks and soil
• Most abiotic factors vary in space and time
© 2011 Pearson Education, Inc.
Temperature
• Environmental temperature is an important factor
in distribution of organisms because of its effects
on biological processes
• Cells may freeze and rupture below 0°C, while
most proteins denature above 45°C
• Mammals and birds expend energy to regulate
their internal temperature
© 2011 Pearson Education, Inc.
Water and Oxygen
• Water availability in habitats is another important
factor in species distribution
• Desert organisms exhibit adaptations for water
conservation
• Water affects oxygen availability as oxygen
diffuses slowly in water
• Oxygen concentrations can be low in deep
oceans and deep lakes
© 2011 Pearson Education, Inc.
Salinity
• Salt concentration affects water balance of
organisms through osmosis
• Most aquatic organisms are restricted to
either freshwater or saltwater habitats
• Few terrestrial organisms are adapted to highsalinity habitats
© 2011 Pearson Education, Inc.
Sunlight
• Light intensity and quality (wavelength) affect
photosynthesis
• Water absorbs light, thus in aquatic
environments most photosynthesis occurs near
the surface
• In deserts, high light levels increase temperature
and can stress plants and animals
© 2011 Pearson Education, Inc.
Figure 52.21
Rocks and Soil
• Many characteristics of soil limit distribution of
plants and thus the animals that feed on them
– Physical structure
– pH
– Mineral composition
© 2011 Pearson Education, Inc.
Figure 52.UN01
Why is species X absent from an area?
Does dispersal limit its distribution?
Yes
Area inaccessible or
insufficient time
No
Does behavior limit its distribution?
Yes
Habitat selection
No
Do biotic factors (other species)
limit its distribution?
No
Do abiotic factors limit
its distribution?
Yes
Predation, parasitism,
competition, disease
Chemical
factors
Water, oxygen, salinity,
pH, soil nutrients, etc.
Physical
factors
Temperature, light, soil
structure, fire, moisture,
etc.
Figure 52.UN02
Mean height (cm)
Figure 52.UN03
100
50
Altitude (m)
0
3,000
2,000
Sierra Nevada
1,000
0
Seed collection sites
Great Basin
Plateau