Download Ecology - AaronFreeman

Ecology
Ecology
(oikos – House or place where one lives and
logos – study of)
Ecology: the study of interactions between
organisms & their environment
Organization of Life
Organism
population
community
ecosystem
Biome
Biosphere
Organization of Life
All living matter can be organized
SMALLEST--> LARGEST.
Ecology deals with the levels
Organisms
Populations
Communities
Ecosystems
Biome
Biosphere
Organism
Organism: individual living thing
Scientists study daily movements,
feeding, or breeding behaviors.
Ex
A deer
A Parasite
Population
Population: group of organisms of one type that
live in the same area.
Compete for food, water, mates, and other resources
Resources determine how big/small a population is
Ecologists may study effects of populations of
organisms on environment
Also study growth rates of populations and predict
future populations
Ex
Many deer
Rabbits
Endangered species
Community
Community: Populations that live together
in a defined area
All organisms in a community depend on other
organisms living there.
Ecologists are concerned with effects on
community when a new species is added or
removed.
Ex
Hawks go up then mice go down
Ecosystem
Ecosystem: community & its
nonliving surroundings.
Ecologists are concerned with
ecosystem stability and knowing what
keeps ecosystems stable.
Ex
Rain forest
Biome
Biome: A group of ecosystems that
make up a specific region for
species to live
Similar climate
Temperature
Elevation
Rainfall
Biosphere
The biosphere is the highest
level of organization.
Biosphere: made up of
entire planet & all its living
& nonliving parts
Ecologists are concerned
with all interactions within
the biosphere.
Living environment= Biotic
factors
Living things are found in air,
on land, in both fresh and salt
water
Biosphere is portion of Earth
that supports life
Biotic factors= all living
organisms found on Earth.
Abiotic: nonliving things on
Earth
Environment--write down 3 ex
Air currents
Temperature
Moisture
Light
Soil
How Organisms interact
Key terms- Autotroph, heterotroph,
scavenger, decomposer, symbiosis,
commensalisms, mutualism,
parasitism, food chain, trophic levels,
and food web
Species Feeding
Relationships
Producer/Autotroph: make their own
food from sun
Ex: plant, tree, fern
Heterotrophs= eat others for
food/nutrients
"I MUST BE A HETEROTROPH I CAN'T MAKE THESE !!"
herbivores
Herbivores: eat plants, Vegetarian!
Squirrel, rabbit
Omnivores and decomposers
Omnivores- energy from meat &
plants
"What shall I eat today...meat or veggies....."
Examples=me, mouse, bacteria
Decomposers: break down/
absorb nutrients from dead
organisms.
Ex: Fungus, mushrooms
Carnivores and Scavengers
Carnivore= meat eaters
Heterotrophs which eat other heterotrophs
Example=lion
Scavenger: gets energy from dead
organism (doesn’t kill-stealer)
They play a beneficial role in ecosystem.
Clean up dead animals
Example=vulture
Matter & Energy in Ecosystems
2 laws for ecosystem function.
1) Flow of Energy
2) Cycling of nutrients
Food Chains
Food Chain: model used to show how
matter & energy move through an
ecosystem.
Nutrients and energy go from
autrotroph--> heterotroph-->decomposers.
Food chains consist of 3-5 links
Never 6, b/c amount of energy left by the 5th is only
a small fraction from the 1st.
Algae Fish  Heron  Alligator
Trophic levels represent links of
the food chain.
trophic level: feeding step for each
organism in a food chain, energy lost with
each step
A food chain represents only one possible
route for transfer of matter & energy
Many other routes exist.
4th trophic level
Top Carnivores
3rd order
consumers
Heterotrophs
3rd tropic level
Omnivores & small
carnivores
2nd order consumers
heterotrophs
2nd trophic level
Herbivores
1st order consumers
heterotrophs
1st trophic Level
Autotrophs
producers
Food Webs
Food Web: interconnected food chains.
Many plants & animals involved.
A food web gives all possible feeding
relationships at a trophic level in a
community.
More natural then food chains… why?
Pyramid of Energy
Illustrates that energy decreases at
each succeeding trophic level.
The total energy transfer from one
trophic level to the next is only about
10%. What happens to the other 90%?
1
10
100
1000
Pyramid of Energy
Top Carnivores
Carnivores
Herbivores
Producers
Pyramid of Numbers
Hawk 1
Robins 10
Grasshopper 100
Grass 1000
Notice the relationship between aerobic cellular respiration and phot
Community Interactions
Where and how organisms live
Every species has a particular
function in its community
Niche: role a species plays in a
community
space, food, and weather, & any
other condition an organism
needs to survive and reproduce
are part of it’s niche
Ex
Fungi= break down of organic matter
Coyotes= keep rodents down
Habitat
A place where organism lives
Ex bird in trees
Prairie dog in grassland burrows
Several species share habitats,
the food, shelter and other
resources of that habitat
Symboitic relationships (living
together)
Competition
Interaction between organisms trying to
obtain the same source
Harms both
Darwin Theory of natural
selection
1) populations have ability to increase size
2) Resources are limited
3) Competition will arise
4) Natural Selection: the strongest (fittest) will
survive
5) Survivors traits passed on to offspring
6) There will be change over time-evolution
Commensalism
One species
benefits and the
other is neither
helped nor
harmed
Org A-helped, B-no
effect
Barnacles on a
whale
Do not harm or
help whale
Barnacles benefit
because constant
moving water
source
Commensalism
Spanish moss
flowering plant that drapes itself
on the branches of trees
Orchids can grow on the moss
The trees are not harmed or
helped but the moss and the
orchids have a place to live.
Predator vs prey “Predation”
One organism hunts another for food
Predators- hunt for food
Prey- organism that predator eats
A(predator) benefit, B (prey) killed
Fox hunts & kills rabbit
Predator vs prey
Although the praying mantis
generally eats insects and small tree
frogs, the female will devour part of
her own mate.
Commonly found in tropical and
warm temperate climates, the
mantis was introduced into the
United States to help control certain
insect populations.
Mutualism: both species benefit
whale shark & tiny
fish: has small fish
that live in its mouth
& clean debris from
its teeth.
The shark gets a
free cleaning and
the fish get lunch
Mutualism
The hippopotamus & little
birds: has little birds that
live on its back which eat
insects off hippo & hippo
does not get bitten
Mutualism
Lichens=mixture of
algae & fungus
Algae produces food
lichen requires (by
photosynthesis),
fungus absorbs vital
nutrients & water for
algae.
Parasitism
one organism benefits at expense of
another
Example
Tapeworm: parasitic worm that infests
intestinal lining
no mouth or digestive tract, able to absorb
partially digested material through their
body surface.
Parasite vs Host
Feeds on host
Lives on body of
host
Depends on host for
life processes
Is fed on
Larger the host is
the more parasites it
can support
May become ill or
die from parasite
Parasites
Sheep Tick
Carnivorous, feeding
on the blood of various
species of birds,
reptiles, and
mammals, including
human beings.
Parasites
The chigger has three pairs
of legs as a larva and four
pairs as a nymph and an
adult.
Chiggers are parasitic on
warm-blooded animals. As
larvae they cling to
vegetation and attach
themselves to any animal
that brushes against them.
Summary of symbiotic
relationships
Relationship
Description
Harmful vs
helpful
Example
Predator & prey
One animal eats
another
One is helped
one is killed
Cat eating a
mouse
Parasitism
One animals
One is helped
feeds off another one is drained
of resources or
killed
Tick living off
a deer
Commensalism
One species
benefits from
another
One is helped
one is not
phased
Barnacles and
a whale
Mutualism
Both rely on
each other
Both are helped Flower and
insect
H2O Cycle
How can carbon move?
#1
#2
#3
#4
#5
HEAT
PRESSURE
#6
The Adventures of Carbon!
#6
#1
#3
#4
#2
#5
Carbon of Life-formulas
Carbon Cycle
How does our contribution to C
cycle effect our environment?
Besides breathing, how do we put C
back in atmosphere?
Combustion of fossil fuels
*Combustion of fossil fuels in
atmosphere creates ACID RAIN.
Ecology of Populations
Terms
Population ecology: study of how & why
populations change
Demographics: study of human
populations
Factors that determine
population change
1) Births
2) Deaths
3) Immigration: movement “in” a
population
4) Emigration: movement “out’ of a
population
Increase or decrease?
Births & immigration > deaths &
emigration?
Deaths & emigration > births &
immigration
Populations DO NOT
experience linear growth
They experience __?____ growth
Bacteria: J-shaped curve
Bacterial cells divide every 20
Bacterial
minutes!!!cells divide every 20 min!!!
Bacterial Growth
Rapid growth:
more bacteria
& more
offspring
Beginning
growth, pop
established
Assumption for graph above:
1) unlimited resources 2) no death
3) all bacteria reproducing
If so, 1 cell=Earth in 7 ft in 48 hrs!
exponential growth meets real world
The leveling off of a population results in a
“s” shaped curve
J vs. S
Fluctuations: inc &
dec of pop
Limits on population growth
Limiting factor: regulates size of a
population (limit pop growth)
2 kinds of limiting factors
Density dependent factors
Density independent factors
2 Types of Limiting factors
Density Dependant:
factors that depend
on density of a
population
EX food, shelter,
water, mates.
Density Independent:
factors that do not
depend on density of
a population
EX: Temp, Storms,
Floods, Drought,
Weather
Population Dynamics
Population dynamics: study of
composition, # of individuals, & factors
that cause change
Purpose for pop dynamic
study
1) observe effects of environmental
change/impact on populations
2) Use pops as environmental quality
indicator
3) Determine if threatened or
endangered
4) Understand pop interactions
Two Factors which cause
change
Density dependent: food, shelter, water
Density Independent: weather,
temperature
Birth Rate: # of young
produced in a given time
Factors that affect population birth rate:
1) # of births
2) time between births
3) Age of 1st reproduction-sexual
maturity
4) Amount & quality of food
Death Rate
Death Rate: # of deaths in population in
a given time
AKA “mortality rate”
Age & sex specific
Sex Ratio
Sex ratio: distribution or # of males &
females within population
Typical sex ratio: 50/50, when uneven
affects population
Mating systems effect
Monogamy: 1 partner for a breeding
season or multiple breeding seasons
90% of birds are monogomous
Polygamy: 2+ mates each season
Deer, lions
Age Structure
Examining individuals at each age level
Prereproductive 0-14
Reproductive 14-44
Postreproductive 45+
Age Structure Diagrams
Human Impact
Habitat Destruction
Habitat destruction: process of
damaging/destroying habitat; cannot
support organism
Biodiversity: variety of life on Earth
Habitat Destruction
Urbanization: increasing population/
growth of city into rural areas
Deforestation: clearance of naturally
occurring forests (logging, burning).
Invasive species: Non-native species
of plants/animals that out-compete
native species in a habitat.
Global Warming
Global warming: theory that world's
avg temp is increasing due to burning
of fossil fuels
Results in higher atmospheric
concentrations of gases (CO2)
Global warming
Greenhouse effect: warming that
results when solar radiation is trapped
by atm,
outgoing thermal radiation blocked by
atmosphere
EX: your car in summer
Global Warming
Greenhouse gases: vapors in lower
atmosphere that reflect solar radiation
back to earth:
Water, carbon dioxide (CO2), methane
(CH4), nitrous oxide (N20), ozone
Global Warming Effects
*Polar icecap melting,
so sea levels rise
animals habitat changing (endangering,
extinction?)
*Weather changes (hurricanes from
warm air)
Ozone Depletion
Dfn: reduction of protective layer in
upper atm by chemical pollution.
Pollutant: Chloroflurocarbons (CFCs)
Effects: skin cancer, cataracts, plant
disease, marine life disruption
(phytoplankton reduced 6-8%)
Acid Deposition
transfer of acids (or acid-forming
substances) from atm to Earth's surface
AKA?
Acid rain
Effects: slowly destroys plant life,
erodes buildings
Natural Resource Use
How do we directly effect natural
resources?
Deforestation, housing
How do we indirectly effect natural
resources?
Green yard creates green pond
Natural Resource Use
Growing fruits/veggies? You may want some
pesticides!
Pesticide: chemical used to kill pests (rodent
/insects)
Bioaccumulation: accumulation of
substances in an organism (pesticides,
organic chemicals)
Bioaccumulation
Chemical gathers in organism faster
than it can be broken down
DDT: dichloro diphenyl trichloroethane
bug spray
Effects: bird lays on egg & it cracks.