Download Populations, Communities, Ecosystems and the Biosphere

Populations, Communities, Ecosystems
and the Biosphere
Population Ecology -- Ch. 26
What factors affect the size and age structure
of a population?
Learning Outcomes
Explain carrying capacity.
Explain life history ecology and population structure.
Compare opportunistic and equilibrial life histories.
Explain life history evolution.
Describe trends in human population growth.
Population Growth
when there are
no restrictions,
populations will
increase exponentially
Population Growth
Where did we hear this before?
Malthus 1766 - 1834
However, in reality, no environment has unlimited resources.
Carrying Capacity
these wood ducks will only nest in holes in particular trees
Carrying Capacity
Population size
(number of individuals)
initial carrying capacity
2
3
4
new carrying capacity
1
Life History Ecology
survivorship trends affect population structure
Type I
Type II
Type III
Life History Ecology
Life History Evolution
control = guppies with predator that eats LARGE guppies
moved = guppies with predator that eats SMALL guppies
Human Populations
Human Populations
Community Ecology
-- Ch. 27
How do different species interact with each other?
Learning Outcomes
Define symbiosis, mutualism, commensalism,
and parasitism.
Explain the interdependence of predator-prey
populations.
Explain ecological succession.
Explain keystone species and consequences
of removal.
Community Ecology
Commensalisn and Mutualism
Predator - prey interactions
lynx - white dashed line
snow hare - solid black line
Parasitism
parasites feed off another organism without killing it
Ecological Succession
Keystone Species
one species that can affect the occurence and/or
abundance of many other species
Keystone Species
when the sea stars were removed, mussels rapidly
took over and many other species disappeared
Ecosystems
-- Ch. 28
light
energy
Producers
plants; photosynthetic
protists and bacteria
energy in
chemical
bonds
materials
cycling
Consumers
animals; fungi; heterotrophic
protists, bacteria, and archaeans
heat energy
Learning Outcomes
Define ecosystem.
Describe food chains, food webs, and trophic levels
(producers, primary consumers, secondary
consumers, decomposers).
Describe ecological pyramids and the distribution
of biomass and energy at the different trophic levels.
Explain the water cycle, carbon cycle,
and nitrogen cycle.
Food Webs
Food webs
Trophic pyramid
top carnivores
(gar and bass)
1.5
carnivores (smaller
fishes, invertebrates)
11
herbivores
(plant-eating fishes,
invertebrates, turtles)
37
producers (algae
and aquatic plants)
5
809
Biomass (kg per m2)
detritivores
(crayfish) and
decomposers
(bacteria)
Ecosystems
ecosystems include all living and non-living
components of the environment
Water availability is a key factor.
Water Cycle
Carbon Cycle
Nitrogen Cycle
Atmospheric CO2
The Biosphere
-- Ch. 29
The Biosphere
Biomes on earth are mainly defined by climate.
Climate
rotation and tilt of the earth influence climate
Climate
Light hitting the earth at the equator has
less atmosphere to travel through
and hits a smaller area of earth’s surface
than a comparable amount of sunlight
hitting at higher latitude.
Climate
air heated by sunlight forms circulation cells
Climate
heat energy from sunlight drives ocean currents
Biomes
hatched = montane/alpine
Tropical Rain Forest
Temperate Forest
Boreal Forest
Temperate Grassland
Chaparral
Desert