Post on 19-May-2015
transcript
Ecosystems
biosphere
ecosystem
community
population
Studying organisms in their environment
organism
Essential questionsWhat limits the production in ecosystems?
How do nutrients move in the ecosystem?
How does energy move through the ecosystem?
EcosystemAll the organisms in a community plus
abiotic factorsecosystems are transformers of energy
& processors of matter
Ecosystems are self-sustainingSunlight is needed only
capture energy transfer energy cycle nutrients
capture energy transfer energy cycle nutrients
biosphere
Ecosystem inputs
constant inputof energyenergy flowsthrough
nutrients cycle
nutrients can only cycle
Inputs: energy nutrients
Inputs: energy nutrients
Don’t forgetthe laws of Physics!
Matter cannotbe created ordestroyed
consumers
decomposers
abioticreservoir
nutrientsmade availableto producers
geologicprocesses
Generalized Nutrient
cycling
consumers
consumers
producers
decomposers
abioticreservoir
nutrientsENTER FOOD CHAIN= made availableto producers
geologicprocesses
Decompositionconnects all trophic levels
return toabioticreservoir
Carbon cycle
CO2 inatmosphere
Diffusion RespirationPhotosynthesis
Photosynthesis
Plants and algae
PlantsAnimals
Industry and home
Combustion of fuels
Animals
Carbonates in sediment
Bicarbonates
Deposition ofdead material
Depositionof deadmaterial
Fossil fuels(oil, gas, coal)
Dissolved CO2
abiotic reservoir: CO2 in atmosphere
enter food chain: photosynthesis = carbon fixation in Calvin cycle
Recycle: decompositionreturn to abiotic: respiration Combustion of fossil fuels
abiotic reservoir: CO2 in atmosphere
enter food chain: photosynthesis = carbon fixation in Calvin cycle
Recycle: decompositionreturn to abiotic: respiration Combustion of fossil fuels
Birds
Herbivores
Plants
amino acids
CarnivoresAtmosphericnitrogen
loss to deep sediments
Fish
Plankton withnitrogen-fixingbacteria
Nitrogen-fixingbacteria(plant roots)
Nitrogen-fixingbacteria (soil)
Denitrifyingbacteria
Death, excretion, feces
Nitrifying bacteria
soil nitrates
excretion
Decomposing bacteria
Ammonifying bacteria
Nitrogen cycle
abiotic reservoir: N in atmosphere
enter food chain: nitrogen fixation
by soil & aquatic bacteria
recycle: decomposing &
nitrifying bacteriareturn to abiotic: denitrifying
bacteria
abiotic reservoir: N in atmosphere
enter food chain: nitrogen fixation
by soil & aquatic bacteria
recycle: decomposing &
nitrifying bacteriareturn to abiotic: denitrifying
bacteria
Lakes
Runoff
Percolation in soil
Evaporation
Transpiration
Precipitation
Oceans
Solar energy
AquiferGroundwater
Water cycle
Water vapor
abiotic reservoir: surface &
atmospheric waterenter food chain: precipitation &
plant uptakerecycle: transpiration
return to abiotic: evaporation &
runoff
abiotic reservoir: surface &
atmospheric waterenter food chain: precipitation &
plant uptakerecycle: transpiration
return to abiotic: evaporation &
runoff
biosphere
Ecosystem inputsenergy flowsthrough
nutrients cycle
inputs energy nutrients
inputs energy nutrients
Energy flows through ecosystems
sun
producers (plants)producers (plants)
loss of energy
loss of energy
secondary consumers(carnivores)
secondary consumers(carnivores)
primary consumers(herbivores)
primary consumers(herbivores)
Food chainsTrophic levels
feeding relationshipsstart with energy from
the sun captured by plants
1st level of all food chainsfood chains usually go
up only 4 or 5 levelsDue to inefficiency of
energy transferall levels connect to
decomposers Fungi
Level 4
Level 3
Level 2
Level 1
Decomposers
Producer
Primary consumer
Secondary consumer
Tertiary consumer
top carnivore
carnivore
herbivore
Bacteria
autotrophs
heterotrophs
sun
Inefficiency of energy transferLoss of energy between levels of food
chainTo where is the energy lost? The cost of living!
only this energymoves on to the next level in the food chain
17%growth
50%waste (feces)
33%cellularrespiration
energy lost todaily livingenergy lost todaily living
sun
Ecological pyramidLoss of energy between levels of food chain
can feed fewer animals in each levelFewr organisms at the top due to energy loss
1,000,000,000
100,000
100
1
sun
Humans in food chains
Dynamics of energy through ecosystems have important implications for human populationshow much energy does it take to feed a
human? if we are meat eaters? Vegetarians?
What is yourecological footprint?!
Food websFood chains are linked
together into food webs
Who eats whom? a species may weave
into web at more than one
levelbearshumans
eating meat?eating plants?