Understanding Ecosystems: Energy Flow, Nutrient Cycling, and Trophic Levels

1. Ecology: Ecosystems Energy Flow Water and Nutrient Cycling

2. Ecosystem Resources • Energy: one way flow from sun to organisms and loss as heat (yellow, red arrows) • Nutrients: move in cycles involving organisms and the environment(purple arrows)

3. Producers Capture the Sun’s Energyand Accumulate Inorganic Nutrients

4. Energy Transfer and Loss Heat SecondaryConsumer PrimaryConsumer Producer Heat DetritusFeeders Chemicals Heat

5. Consumers Gain Energy as Organic Molecules from Producers HerbivoreEats Producers Carnivore Eats Primary Consumers Food Chains Carnivore Eats Secondary Consumers

6. 4 3 4 3 2 2 2 1 2 2 3 1 2 3 3 2 4 3 2 Food Web • Shows interconnected food chains • Trophic Levels 1) producer 2) primary consumer 3) secondary consumer 4) tertiary consumer

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

8. Concentration of Contaminants at Higher Levels of Food Chains 0.005 ppm DDT 0.00003 ppm DDT 0.01 ppm DDT 10 ppm DDT

9. detritus feeders and decomposers Detritus Feeders and Decomposers Release Nutrients for Reuse Animals and Protists that feed on plant and animal remains Fungi and Bacteria that break down decaying material

10. Applying Your Knowledge • Primary Consumer • Secondary Consumer • Tertiary Consumer • Producer Which level best represents: • a palm tree? • a bird eating seeds? • a student consuming a beefsteak?

11. Animal cells produce proteins and nucleic acids Plants are eaten by animals Soil bacteria release nitrogen from decaying matter Ammonium is converted to nucleic acids and proteins N2 gas becomes ammonia or ammonium Ammonia is converted to nitrites or nitrates Nitrate is broken down to produce N2 gas Nitrate is taken up by plants and converted to ammonium The Nitrogen Cycle Plants and animals die and begin to decay Ammonification Nitrogen Fixation Nitrification Assimilation Denitrification

12. The Nitrogen Cycle Reservoirs Nitrogen inAtmosphereReservoir Nitrogen inAtmosphereReservoir Electrical stormsproduce nitrate Nitrogen inAtmosphereReservoir Processes/Locations TrophicLevels/Organisms Consumers Producers Wastes,Dead bodies Uptakebyplants Dentitrifyingbacteria Nitrogen-fixingbacteria inlegume rootsand soil Soil bacteria anddetritus feeders Ammonia& nitrate Ammonia& nitrate Ammonia& nitrate

13. The Carbon Cycle CO2 inatmosphere(reservoir) CO2 dissolvedin ocean(reservoir) CO2 inatmosphere(reservoir) CO2 inatmosphere(reservoir) CO2 inatmosphere(reservoir) CO2 inatmosphere(reservoir) CO2 inatmosphere(reservoir) CO2 inatmosphere(reservoir) CO2 inatmosphere(reservoir) Burning offossil fuels Reservoirs Fire Respiration Processes/Locations Photosynthesis TrophicLevels/Organisms Producers Consumers Consumers Wastes,Dead bodies Wastes,Dead bodies Wastes,Dead bodies Soil bacteria &detritus feeders Soil bacteria &detritus feeders Soil bacteria &detritus feeders

14. Global Warming Parallels CO2 Increases

15. Greenhouse GasesContribute to Global Warming

16. CFCs Contribute to the Formation of a Hole in the Protective Ozone Layer South America Antarctica The “hole”

17. Water vaporin atmosphere Water vaporin atmosphere The Water Cycle Evaporationfrom land &transpirationfrom plants Evaporationfrom ocean Alternates between Evaporation and Precipitation Precipitationover ocean Precipitationover land Water inocean(reservoir) Water inocean(reservoir) Water inocean(reservoir) Surfacerunoff Reservoirs Processes/Locations Groundwaterseepage

18. Water Carrying Industrial Pollutants Can Become Acid Rain

19. Applying Your Knowledge • Ammonification • Assimilation • Denitrification • Nitrification • Nitrogen Fixation Which term describes: • uptake of nitrogen-containing compounds by plants? • conversion of nitrogen gas to nitrates? • release of nitrogen gas from nitrates?

20. Applying Your Knowledge • Water Cycle • Food Chain • Nitrogen Cycle • Carbon Cycle Which process is related to: • concentration of toxic minerals in animal tissues? • global warming? • acid rain?