Ecology: EcosystemsEcology: Ecosystems

Ecosystem ResourcesEcosystem Resources

Energy: one way flow Energy: one way flow from sun to organisms from sun to organisms and loss as heat and loss as heat (yellow, red arrows)(yellow, red arrows)

Nutrients: move in cycles Nutrients: move in cycles involving organisms and involving organisms and the environment the environment (purple arrows)(purple arrows)

Consumers Gain Energy as Organic Consumers Gain Energy as Organic Molecules from ProducersMolecules from Producers

HerbivoreEats

Producers

Carnivore Eats

Primary Consumers

Carnivore Eats

Secondary Consumers

Food Food ChainsChains

Food WebFood Web•ShowsShows interconnected interconnected food chains food chains

•Trophic LevelsTrophic Levels

1) producer 1) producer

2) primary consumer 2) primary consumer

3) secondary consumer 3) secondary consumer

4) tertiary consumer 4) tertiary consumer

11

1122

22

22

2222

22

2222

33

33

33

33

3333 44

44

44

Energy Transfer and LossEnergy Transfer and LossHeatHeat

HeatHeat

ProducerProducer

PrimaryPrimaryConsumerConsumer

SecondarySecondaryConsumerConsumer

DetritusDetritusFeedersFeedersHeatHeatHeatHeat

ChemicalsChemicalsChemicalsChemicals

Efficiency of Energy Transfer Efficiency of Energy Transfer ~10% of calories to next trophic level~10% of calories to next trophic level

Concentration of Contaminants at Concentration of Contaminants at Higher Levels of Food ChainsHigher Levels of Food Chains

0.00003 ppm DDT

0.005 ppm DDT

0.01 ppm DDT

10 ppm DDT

Detritus Feeders and Decomposers Detritus Feeders and Decomposers Release Nutrients for ReuseRelease Nutrients for Reuse

detritus feeders and decomposers

Animals and Protists that feed

on plant and animal remains

Fungi and Bacteria that break down

decaying material

The Nitrogen CycleThe Nitrogen Cycle Plants and animals die Plants and animals die and begin to decayand begin to decay

Soil bacteria release Soil bacteria release nitrogen from nitrogen from decaying matterdecaying matter

Nitrate is brokenNitrate is brokendown to produce down to produce NN22 gas gas

Ammonia is Ammonia is convertedconvertedto nitrites or to nitrites or nitratesnitrates

Plants are eaten Plants are eaten by animalsby animals

NN22 gas becomes gas becomes

ammonia ammonia or ammoniumor ammonium

Nitrate is taken up by Nitrate is taken up by plants and converted plants and converted to ammoniumto ammonium

Ammonium is Ammonium is convertedconvertedto nucleic acids to nucleic acids and proteinsand proteins

Animal cells Animal cells produceproduceproteins and proteins and nucleic acidsnucleic acids

Ammonification

Nitrification

Assimilation

Denitrification

Nitrogen Fixation

Nitrogen inNitrogen inAtmosphereAtmosphere

ReservoirReservoir

Nitrogen inNitrogen inAtmosphereAtmosphere

ReservoirReservoir

The Nitrogen CycleThe Nitrogen Cycle

Electrical stormsElectrical stormsproduce nitrateproduce nitrate

AmmoniaAmmonia& nitrate& nitrate

Nitrogen-fixingNitrogen-fixingbacteria inbacteria in

legume rootslegume rootsand soiland soilAmmoniaAmmonia

& nitrate& nitrate

UptakeUptakebyby

plantsplants

ProducersProducers ConsumersConsumers

Wastes,Wastes,Dead bodiesDead bodies

Soil bacteria andSoil bacteria anddetritus feedersdetritus feeders

AmmoniaAmmonia& nitrate& nitrate

DentitrifyingDentitrifyingbacteriabacteria

Nitrogen inNitrogen inAtmosphereAtmosphere

ReservoirReservoir

ReservoirsReservoirs

Processes/Processes/LocationsLocations

TrophicTrophicLevels/Levels/

OrganismsOrganisms

The The Water Water CycleCycle

EvaporationEvaporationfrom land &from land &transpirationtranspirationfrom plantsfrom plants

PrecipitationPrecipitationover landover land

Water vaporWater vaporin atmospherein atmosphere

Water inWater inoceanocean

(reservoir)(reservoir)

EvaporationEvaporationfrom oceanfrom ocean

Water vaporWater vaporin atmospherein atmosphere

Water inWater inoceanocean

(reservoir)(reservoir)

GroundwaterGroundwaterseepageseepage

SurfaceSurfacerunoffrunoff

Water inWater inoceanocean

(reservoir)(reservoir)

PrecipitationPrecipitationover oceanover ocean

ReservoirsReservoirs

Processes/Processes/LocationsLocations

Alternates Alternates between between

Evaporation Evaporation and and

PrecipitationPrecipitation

Water Carrying Industrial Pollutants Water Carrying Industrial Pollutants Can Become Acid RainCan Become Acid Rain