Transcript Ecology/energy

Ecology:
Energy Flow
What is Ecology:
 scientific study of the interactions among
same organisms
 and between other organisms and their
environment
I. Overview
A. Organizational levels of ecology
B. Tools scientists use to study ecology
C. Energy Flow in Ecosystems
D. Ecological Pyramids
E. Cycles in Nature
A. Organizational levels
1.
2.
3.
4.
Organism: Species
Populations: all members of the same species
Communities: all populations living together.
Ecosystem: community + environmental factors
affecting the community in the given area.
5. Biome: all ecosystems with the same
environmental conditions  Biosphere
B.
1.
Tools used by the ecologist to study
ecology:
Tools can be anything (binoculars, shovels, etc) but all
study fits into three basic approaches.
i. Observations
ii. Experimentation
iii. Modeling
2.
3.
4.
observations-any of the 5
senses!!!
In 2002, beach pollution prompted
at least 12,814 closings and
swimming advisories at ocean,
bay, Great Lakes, and some
freshwater beaches
(87%) of closings and advisories
in 2002 were issued after
monitoring revealed the presence
of bacteria associated with fecal
contamination (source unknown in
most cases).
http://www.dmr.state.ms.us/Coastal-Ecology/Preserves/Pollution/pollution.htm
3. Experimentatio
n: from the field
to the laboratory
i. Counting
Deer Herds.
ii. Pests and
their effects
iii. DNA
assessment.
First-year Columbia University students sift through debris looking for ants during a
Frontiers of Science Field experiment in Morningside Park
4. Modeling:
Attempt to
simulate the
real conditions.
i. Global
warming
model
ii. Humidity
chambers.
http://ag.arizona.edu/~lmilich/antartic.gif
C. Energy Flow: “sunlight is main
source of energy”
1. Producers:
a.
Autotrophs (can build own food using suns energy)
b. Use photosynthesis.
c.
3% energy that hits the earth
d. Store energy in sugars and other organic molecules.
e. ** a few use chemical energy instead of the sun
(chemobacteria)
Cyanobacteria/blue-green algae
Watermelon plant
Carrot plant
Apple trees
2. Consumers: cannot build own food! Rely on other
organisms for their energy and food supply.
a. Also called : heterotrophs.
b. Several types including;
i.
Herbivore: consumes producers (cows, rodents, squirrels)
ii.
Carnivore: consumes herbivores or other carnivores
(mountain lions, snakes and other meat eating animals)
iii.
Omnivore: consume both plant and animal (Bears, chimps,
monkeys, humans)
iv.
Detritivore: consume animal and plant remains.
(earthworm, snail, crab, sea gull)
v.
Decomposer: breaks down organic matter. (bacteria, fungi)
Herbivore: consumes producers
Carnivore: consumes herbivores or
other carnivores
Omnivore
Detritivore
Decomposer:
3. Usually displayed as food chains (see figure 3-7)
4. In nature, usually exists as a food web (see figure 3-8)
5. What is the difference?
6. Each step in a food chain or food web is called a
“TROPHIC LEVEL”
Go to
Section:
D. Ecological pyramids: The amount of energy or
matter in each trophic level can be represented by
a pyramid.
i. Three different pyramids including;
a. Energy pyramid
b. Biomass pyramid
c. Numbers pyramid
d. See fig 3-9
Energy Pyramid
Shows the relative amount of
energy available at each trophic
level. Organisms use about 10
percent of this energy for life processes.
The rest is lost as heat.
Go to
Section:
Biomass Pyramid
Represents the amount of
living organic matter at each
trophic level. Typically, the
greatest biomass is at the
base of the pyramid.
Pyramid of Numbers
Shows the relative
number of individual
organisms at each
trophic level.
E. Cycles of Matter: Unlike energy, matter must be
used over and over. (water and nutrients)
1. Water cycle:
a) Evaporation
b) Transpiration, perspiration
c) Condensation
d) Precipitation: rain, snow, sleet
e) Runoff
a) Seepage.
b) See figure 3-11
Water Cycle
Condensation
Precipitation
Evaporation
Transpiration
Runoff
Seepage
Root
Uptake
2. Carbon cycle: key nutrient to all living systems
a) All organic molecules contain carbon
b) Photosynthesis, respiration
c) Decomposition by bacteria and fungi’s
d) Volcanic gases
e) Combustion of coal and fossil fuels.
f) Burning of rain forests
g) See figure 3-13
Carbon Cycle
CO2 in
Atmosphere
CO2 in Ocean
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Section:
3. Nitrogen cycle: amino acids, ATP, DNA, and RNA all
contain nitrogen. A very important nutrient.
a) Nitrogen fixation: convert nitrogen gas to ammonia. This can be
used by plants.
b) Denitrification: convert nitrates back to nitrogen gas.
c) Various decomposition by living organisms.
d) See figure 3-14
Nitrogen Cycle
N2 in Atmosphere
NH3
NO3and NO2-
4. Phosphorus also recycles.
a) Needed in DNA, ATP and RNA.
b) Does not recycle through the atmosphere like others.
c) See figure 3-15 in textbook.
5. Nutrient limitations:
a) Growth is slowed.
b) Sick Lawn…Fertilize. Ammonium sulfate(20% N), Urea(40%
N) all have a percentage of Nitrogen
c) Sick lake with to many nutrients: “algal bloom:
figure 3-16.
See picture on
Assignments
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Kernel lab
Seed lab
Chapter 2 questions 1-20
Cycles in nature quick facts