Transcript Bio Ch3 Ecology 2013

ECOLOGY
The SHORT version
Biology Ch 3
Levels of
Ecological
Organization
Biosphere – combined portions of Earth that include & interacts with living organisms
Biome – group of ecosystems with same climate & similar dominant communities
Ecosystem – collection of all organisms in one place & abiotic factors
Community – populations that live together in one place
Population – groups of individuals that live together in same area
Species – individuals in same are that can produce fertile offspring
Ecological Methods
Computer
Modeling
Observation
Experimentation
Energy Flow
PRODUCERS
 Autotrophs
 Photosynthesis
 Chemosynthesis
Consumers
 Heterotrophs
 Herbivores
 Carnivores
 Omnivores
 Detritivores
 Decomposers
Food Chain
Energy relationship between organisms in ecosystem
Food Web
Trophic Levels
Trophic Levels
Specific level
(relationship) that an
organism occupies in a
food chain
Ecological Pyramids
• Energy
• Biomass
• Pyramid of numbers
Energy Pyramid
Shows relative amount
of energy available at
each trophic level
Only 10% of
available energy
transferred from
one trophic level to
the next
Biomass
Pyramid
Represents amount
of living organic
matter at each level
10% transferred
between levels
Pyramid of Numbers
Relative number of organisms
at each trophic level
Only about 10% transferred
between levels
Pyramid of Numbers for oak tree community
Biogeochemical Cycles
Biological,
geological, &
chemical matter
recycled through
ecosystems
WATER CYCLE
Nutrient Cycles
Carbon Cycle
Biological processes
(photosynthesis, respiration,
decomposition) take up & release
carbon
Geochemical processes (erosion,
volcanic activity) release CO2 into the
atmosphere
Mixed processes (burial &
decomposition of dead organisms
converting to petroleum) store
carbon underground
Human activities (mining,
forestation, burning fossil fuels)
release CO2 into atmosphere
Used in forming DNA/RNA
Not in atmosphere, just soil
and water
Nitrogen Cycle
 All organisms require nitrogen
to build proteins
N2 is in atmosphere
Nitrogen fixation – bacteria
convert N2 to NH3 in soil, used as
nutrients for producers
Denitrification – bacteria
convert NH3 to N2 in atmosphere
Limiting Factors
Primary productivity
 Rate at which organic matter is created by producers
Limiting factors
 Abiotic - ???
Biotic - ???
OVERVIEW