What is Ecology? Study of the relationship between organisms AND between organisms and their...
Transcript of What is Ecology? Study of the relationship between organisms AND between organisms and their...
What is Ecology?
• Study of the relationship between organisms AND between organisms and their environment
Organization of the Living World
Biosphere
Ecosystem
Community
Population
IndividualSmallest
to
Largest
Population
All the members of the same species that live in the same area
Community
All populations of organismsliving in the same place
Ecosystem
All biotic and abiotic factorsin a particular environment
BIOSPHERE
All regions of the earth where life can exist
Abiotic vs. Biotic Factors
Abiotic (nonliving)
- soil, temperature, sunlight, water, gases, minerals, etc.
Biotic (living)
- Any living thing (all depend on abiotic factors for survival)
Habitat vs. Niche
Habitat - an organism’s environment (ex. A forest)
Niche - an organism’s role in its environment (ex. Producing oxygen (plants))
Niche of Organism A
Niche of Organism B
Competition
When niches of 2 organisms overlap, competition results
Symbiotic Relationships
Relationship between two organisms in which one organism benefits
Symbiotic Relationships
• Mutualism - both organisms benefit from relationship (+,+)
• Parasitism - one organism benefits at the expense of the other (+, -)
• Commensalism - one organism benefits while the other is unaffected (+, 0)
Energy Flow through an Ecosystem
Food Chains and Food Webs
Energy Flow
• The source of all energy on earth is the sun
• The sun’s energy is trapped by plants in photosynthesis and transformed into carbohydrates
• Energy is measured in calories (kcal)
How do organisms get energy? The trophic levels
• Producers (autotrophs)
• Consumers* (heterotrophs):
- primary (herbivores - eat only producers)
- secondary (eat primary consumers)
- tertiary (eat secondary consumers)
*A consumer can be all three types at the same time (omnivore)
Food Chains and Webs
• Show the path of energy through an ecosystem
• Arrows follow the direction of energy flow
• All food chains and webs have producers at the base
Food Webs
• Food webs show many food chains and how they are connected to each other
• Food webs are more accurate representations of the true relationships between organisms
Example of a food web
Energy Flow in a Food Web
• At each step in the food chain, 90% of the energy is lost as heat
• Each organism in the chain receives 10% of the energy from the organism it consumes (except for producers which get their energy from the sun)
In the diagram above, only 10%of the available energy is passedon to each trophic level
Pyramid of Energy and Biomass
Biomass - total amount of living tissue
Pyramid of Energy and Biomass
producers
Primary consumers
Secondary consumers
Tertiary consumers
Decr
easi
ng b
iom
ass
Decr
easi
ng e
nerg
y
Pyramid of Energy and Biomass
producers
PC
SC
TCHEAT
1000 calories
100 calories
10 calories
1 calorie
Cycling of Matter vs. Energy
• Matter is recycled as it passes through any ecosystem.
• Energy is not recycled. It is used up by each organism
Water cycle
evaporationprecipitation
Transpiration(excess water exits through the leavesas water vapor)
runoff
Condensation to form clouds
Uptake throughroots
The Water Cyclegroundwater
Water vaporRises and cools
CO2
(air)
ConsumersProducersmake Carbohydrates
(photosynthesis)
photosynthesis respiration
decomposers
Death &
decay
Death
& d
ecayre
spir
ati
on
Fossil fuels (oil, coal)
Millions of years, high pressureand temperature
Factories, cars
Use
d a
s en
ergy
for
combustion
CARBON CYCLE
respira
tion
N2
(gas)
Nitrates (in soil)Ammonia(in soil)
Bacteria change ammonia into
N2 fixing bacteriachange N2 gas into
plants
Used by
Consumers
Eaten by
Ammonia (in soil)
Dec
ompo
sition
Aft
er d
eath
(by
Dec
ompo
sers
)
Denitrifying bacteriaChange nitrates to N2 gas
NITROGEN CYCLE
Decomposition
After death
Bacteria changeammonia into
Phosphate(soil)
Consumers
Producers
Eaten byUptake through roots Die & decompose
Aquatic producers and consumers die
Body ofwater (lakes,oceans, etc.)
PHOSPHORUS CYCLE
Phosphates in soilseep into streams
Rocks & sediments
Die & decompose