Transcript Ecosystems - AaronFreeman

Ecosystems
And Energy Flow
Ecology

The study of how
organisms interact
with one another and
with their nonliving
environment
Organization of Life
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Cells --> --> Organisms --> populations -->
communities --> ecosystems --> biosphere
P. 66 Fig. 4-2
-living part of Earth
Biosphere
= community + environment
-biotic & abiotic factors
Ecosystems
-Cycling of nutrients
-pop. of different species
-type of species
Communities
-# of species
-relationships b/n species
Species = similar organisms,
produce offspring
- members of same species
Populations
Organisms
Spheres of Earth
Troposphere~ 0-11 miles above earth
Contains the majority of Earth’s air, contains bad
ozone O3
Stratosphere~ 11-30 miles above earth
The ozone layer, good ozone O3 (sunscreen)
Lithosphere~ Crust and Mantle
Important for nonrenewable resources
Soil nutrients for plants
Ecosphere~aka Biosphere; 12 miles beneath sea
level to the highest mountain
Life is only found in this layer
Hydrosphere~ Water, ice, & water vapor
p. 68 Fig. 4-6
Atmosphere
Biosphere
Vegetation and animals
Soil
Crust
Rock
core
Lithosphere
Mantle
Crust
Crust
(soil and rock)
Biosphere
(Living and dead
organisms)
Hydrosphere
(water)
Lithosphere
(crust, top of upper mantle)
Atmosphere
(air)
Life on
Earth
depends
on:
Energy
flow
Biosphere
Carbon
cycle
Phosphorus
cycle
Nitrogen
cycle
Water
cycle
Oxygen
cycle
Element
cycling
Gravity
p. 69 Fig. 4-7
Heat in the environment
Heat
Heat
Heat
PHOTOSYNTHESIS
light + 6CO2 + 12H20 --> C6H12O6 + 6O2 + 6H20
RESPIRATION
C6H12O6 + 6O2 --> 6CO2 + 6H2O + energy
Components of Ecosystems
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Abiotic (nonliving) - water, air, nutrients,
solar energy
Biotic (living) - plants, animals, microorganisms
Adjacent
Ecosystems
Ecotone
Land zone
Transition zone
Number
of species
Species in land zone
Species in aquatic zone
Species in transition
zone only
Aquatic zone
Notice the
lack of
sharp
Boundaries
Great
Diversity
Sun
Producers (rooted plants)
Producers (phytoplankton)
Primary consumers (zooplankton)
Secondary consumer (fish)
Dissolved
chemicals
Tertiary consumer
(turtle)
Sediment
Decomposers (bacteria and fungi)
Oxygen (O2)
Sun
Producer
Carbon dioxide (rabbit)
Primary consumer
(rabbit)
Falling leaves
Precipitation
and twigs
Secondary consumer
(fox)
Producers
Soil decomposers
Water
Soluble mineral nutrients
Abiotic Factors
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NONLIVING physical and chemical
factors which affect the ability of
organisms to survive and reproduce
Different species thrive under different
conditions
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Temperature, weather, water availability
Sunlight
pH
p. 73 Fig. 4-13
Abiotic Factors
Terrestrial Ecosystems
Aquatic Life Zones
• Sunlight
• Temperature
• Light penetration
• Precipitation
• Water currents
• Wind
• Dissolved nutrient
concentrations
(especially N and P)
• Latitude
(distance from equator)
• Altitude
(distance above sea level)
• Fire frequency
• Soil
• Suspended solids
Biotic Factors
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LIVING components of ecosystem
Producers (autotrophs)
Primary consumers (heterotrophs)
Secondary & tertiary consumers
Carnivores, Herbivores, Omnivores
Decomposers (recyclers) - Detritus Feeders
Detritus feeders
Bark beetle
engraving
Long-horned
beetle holes
Carpenter
ant
galleries
Decomposers
Termite and
carpenter
ant
work
Dry rot fungus
Wood
reduced
to powder
Time progression
Fig. 4.15, p. 75 BIOTIC ROLES in environment
Mushroom
Powder broken down by decomposers
into plant nutrients in soil
Heat
Abiotic chemicals
(carbon dioxide,
oxygen, nitrogen,
minerals)
Heat
Solar
energy
Heat
Decomposers
(bacteria, fungus)
Heat
Producers
(plants)
Consumers
(herbivores,
carnivores)
HEAT = low quality
energy
Heat
Food Webs and Energy Flow
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Food chain
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Food web
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Linear sequence depicting the flow of energy
between organisms
Trophic levels = feeding levels
Producers --> primary consumers --> secondary
consumers --> tertiary consumers
Interconnected, complex food chain
Arrows drawn in direction of energy flow
FROM PREY --> TO PREDATOR
FOOD CHAIN - linear flow of energy
Heat
p. 77 Fig. 4-18
First Trophic
Level
Second Trophic
Level
Third Trophic
Level
Fourth Trophic
Level
Producers
(plants)
Primary
consumers
(herbivores)
Secondary
consumers
(carnivores)
Tertiary
consumers
(top carnivores)
Heat
Heat
Heat
Solar
energy
Heat
Heat
Heat
Detritivores (NUTRIENT RECYCLERS)
(decomposers and detritus feeders)
FOOD WEB
Humans
Blue whale
Sperm whale
p. 78 Fig. 4-19
Killer
whale
Elephant
seal
-locate producers
Crabeater seal
-locate
consumers
Leopard
seal
-trophic levels
Emperor
penguin
Adélie
penguins
Petrel
- top consumers
Squid
Fish
Carnivorous plankton
Herbivorous
zooplankton
Krill
Phytoplankton
Pyramid of Energy Flow
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Loss in energy b/n successive trophic levels
10% gets transferred
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Explains…
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Why there are few top carnivores (eagles,
hawks, tigers, white sharks)
Why such species are first to suffer when the
ecosystems that support them are disrupted
Why these species are so vulnerable to
extinction
Heat
Heat
Tertiary
consumers
(human)
Decomposers
Heat
10
Secondary
consumers
(perch)
100
1,000
Heat
Primary
consumers
(zooplankton)
10,000
Producers
Usable energy (phytoplankton)
Available at
Each tropic level
(in kilocalories)
Heat
Energy
Input:
1,700,000
kilocalories
Incoming solar energy
not harnessed
1,679,190
(98.8%)
Energy
Transfers
Waste,
remains
20,810
(1.2%)
Producers
4,245
Metabolic heat,
export
3,368 13,197
Herbivores
5,060
Top carnivores
21
Carnivores
Herbivores
383
3,368
720
383
2,265
Carnivores
90
21
Top
carnivores
5
272
16
Decomposers,
detritivores
Energy Output
Total Annual Energy Flow
20,810 + 1,679,190
1,700,000 (100%)
Producers
20,810
Decomposers/detritivores
Graphs of biomass of organisms in the various trophic levels for
two ecosystems. The size of each square represents dry
weight per square meter of all organisms at that trophic level.
Tertiary consumers
Secondary consumers
Primary consumers
Producers
Abandoned Field
Ocean
Generalized graphs of numbers of organisms in the various
trophic levels for two ecosystems.
Grassland
(summer)
Temperate Forest
(summer)
Tertiary consumers
Secondary consumers
Primary consumers
Producers
Fig. 4.23, p. 86
Primary Productivity
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An ecosystem’s gross primary productivity
(GPP) = Rate at which an ecosystem’s
producers convert solar energy into
chemical energy as biomass
Net primary productivity (NPP) =
{Rate at which producers store chemical
energy as biomass <photosynthesis>} - {Rate
at which producers use chemical energy
stored as biomass <aerobic respiration>}
Variation in productivity on Earth
High productivity -- green
Low productivity -- yellow
Fig. 4.24, p. 87
Estuaries
Swamps and marshes
Tropical rain forest
Temperate forest
Northern coniferous forest (taiga)
Savanna
Agricultural land
Woodland and shrubland
Temperate grassland
Lakes and streams
Continental shelf
Open ocean
Tundra (arctic and alpine)
Desert scrub
Extreme desert
800 1,600 2,400 3,200 4,000 4,800 5,600 6,400 7,200 8,000 8,800 9,600
Average net primary productivity (kcal/m2/yr)
Estimated annual average of NPP per unit area in major
life zones and ecosystems
Fig. 4.25, p. 88
63%
Not used by Humans
Human use of the
biomass produced by
photosynthesis
3%
Used Directly
8%
Lost or Degrades Land
16%
Altered by Human Activity
Fig. 4.26
Ecologists
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Field research
GIS (geographic
information systems)
Lab research
Systems analysis
Define objectives
Systems
Measurement
Data
Analysis
Identify and inventory variables
Obtain baseline data on variables
Make statistical analysis of relationships among variables
Determine significant interactions
System
Modeling
Construct mathematical model describing
interactions among variables
System
Simulation
Run the model on a computer, with values
entered for different variables
System
Optimization
Evaluate best ways to achieve objectives
Systems Analysis
Fig. 4.35, p. 98
Solar
Capital
Water
resources
and
purification
Air
resources
and
purification
Climate
control
Ecosystem services
Recycling
vital
chemicals
Renewable
energy
resources
Soil
formation
and
renewal
Natural
Capital
Nonrenewable
energy
resources
Waste
removal and
detoxification
Natural
pest and
disease
control
Biodiversity
and gene
pool
Potentially
renewable
matter
resources
Nonrenewable
mineral
resources
Fig. 4.36, p. 99