EEE 105

http://life.uiuc.edu/animalbiology/105/ID: eee105Password: prAIRie

Lec4 1/23/02

EcosystemsEcosystemsEcosystemsEcosystems

The pattern of interaction between The pattern of interaction between organisms and their physical organisms and their physical environmentenvironment

EnergyEnergy

MaterialsMaterials

InformationInformation

EnergyEnergy

Energy

Energy flows through ecosystems beginning with photosynthesis

CO2 + H2O C6H12O6 + O2sugars carbon

dioxide

oxygen

Energy

biological energy

EnergyPhotosynthesis evolved more than 2 billion years ago

CO2 + H2O C6H12O6 + O2sugars carbon

dioxide

oxygen

in the cyanobacteria

EnergyPhotosynthesis evolved more than 2 billion years ago

CO2 + H2O C6H12O6 + O2sugars carbon

dioxide

oxygen

in the cyanobacteria

Energy

causing the greatest environmental disaster

Photosynthesis evolved more than 2 billion years ago

CO2 + H2O C6H12O6 + O2sugars carbon

dioxide

oxygen

in the cyanobacteria

an oxidizing atmosphere

Energy

Photosynthesis occurs in the chloroplasts of green plants

EnergyChloroplasts evolved from photosynthetic bacteria

Endosymbiosis

EnergyEnergy flows through ecosystems

plants

energy

respirationCO2 + H2O

C6H12O6sugars carbon

dioxide

+ O2

Releases energy

For growth & maintenance

Energy flows through ecosystems

(photosynthesis)

EnergyEnergy flows through ecosystems

plants

energy

respiration

Energy flows through ecosystems

decompositionDeath of plants

EnergyEnergy flows through ecosystems

plants

energy

respiration

Energy flows through ecosystems

decomposition

calories ofenergy

Growth &reproduction= netproductivity

biomass

Energy budgets

plants

energy

respiration

decomposition

biomass

calories ofenergy

Growth &reproduction= netproductivity

Energy

Measured in calories

Energy strategies

Energy

growth vs. reproduction

EnergyEnergy strategies

growth vs. reproduction

r vs. K strategies

grass is an r strategistgrass is an r strategist

bracken fern is rbracken fern is r

trees are Ktrees are K

Energy strategies

Energy

growth vs. reproduction

r vs. K strategies

many small vs. fewer large seedsmany small vs. fewer large seeds

Energy strategies

Energy

growth vs. reproduction

r vs. K strategies

many small vs. fewer large seeds

Energy strategies

Energy

growth vs. reproduction

r vs. K strategies

many small vs. fewer large seeds

plants

respiration

decomposition

calories ofenergy

biomassprimary

consumer

ProducerProducer

decomposition& waste

respiration& behavior

Energy

Animal energy strategiesAnimal energy strategies

plants

respiration

decomposition

calories ofenergy

biomassprimary

consumer

ProducerProducer

decomposition& waste

respiration& behavior

Energy

Animal energy strategies

Energy

r vs. K strategies

Animal energy strategies

Energy

r vs. K strategies

Bumblebee Economicsby Berndt Heinrich

Bumblebee Economicsby Berndt Heinrich

Animal energy strategies

Energy

r vs. K strategies

“warm-blooded” vs. “cold-blooded”

(endothermy vs. exothermy)

plants

respiration

decomposition

calories ofenergy

biomassprimary

consumer

ProducerProducer

Energy

secondarysecondaryconsumerconsumer

Energy flows through ecosystemsEnergy flows through ecosystems

plants

respiration

decomposition

calories ofenergy

biomassprimary

consumer

ProducerProducer

Energy

secondarysecondaryconsumerconsumer

Energy flows through ecosystems

EnergyFood chain

E

producer primary secondaryconsumer consumer

Trophic levels

autotroph herbivore predator

heterotrophs

Why a pyramid?Why a pyramid?

EnergyFood chain

E

producer primary secondaryconsumer consumer

Trophic levels

autotroph herbivore predator

respiration

decomposition

90% used at each trophic level

EnergyFood webs

EnergyFood chain

E

producer primary secondaryconsumer consumer

Trophic levels

autotroph herbivore predator

respiration

decomposition

90% used at each trophic level

Photosynthetic food chain

EnergyDetritus food chains

detritus = dead and excreted material

detritus

EnergyFood chain

E

producer primary secondaryconsumer consumer

Trophic levels

respiration

90% used at each trophic level

Photosynthetic food chain

EnergyDetritus food chains

detritus = dead and excreted material

EnergyStrangest food chain

first found off the Galapagos

EnergyStrangest food chain

hydrothermal vents

EnergyStrangest food chain

hydrothermal vents

“gutless” vent worms

ArchaeaArchaea

endosymbiosisendosymbiosis

a chemosynthetic food chaina chemosynthetic food chain

EnergyFood chains

photosynthetic

detritus

chemosynthetic