OUR Ecological Footprint 1. Live near work; ride bike; minimize car use. 2. Buy energy-efficient furnace. 3. Programmable thermostat: 50 winter/ 80 summer 4. Turn off lights when leave room; unplug appliance 5. Eat low on food chain. 6. Buy food locally; eliminate transportation energy. 7. Buy hybrid car - reduce gas consumption by 1/2 8. Get ‘on demand’ water heater. 9. Winterize house. 10. Recycle; pay tax for it. 11. Reduce paper/plastic (and ALL) consumption. 12. Reuse (and repair) items; don’t use ‘throw- aways’ 13. Restore: Buy C offset for travel--> plant trees.…For TuesdayOur ‘stuff’… or “how humans alter nutrient cycles and deplete natural resources…”OBJECTIVESIntersystem cycling: Nutrients gained (input) and lost (output) by an ecosystemEcosystems modeled as linked compartments (box = pool; arrow = flux).Nutrient inputs on land from:Nutrient losses (output) on land to:Plowing of prairies contributed to the creation of the Midwest’s Dust Bowl (1930s).Soil erosion on plowed farmland…about 1% of topsoil is lost each year.Over-grazing leads to loss of vegetation and leads to soil erosion.WATERWater use greatly exceeds water supplies in many parts of our West.Irrigation can turn desert into productive farmland…But…accumulation of salts in soil that accompanies irrigation can damage crops.Clear-cutting affects hydrology, erosion, nutrient-off…50% of water in the Amazon Basin is internally recycled. Predict how deforestation there might be affecting the local hydrologic (water) cycle and the forest.How are humans altering water cycle?CARBON --> Global warmingHuman production of CO2 by burning of fossil fuels has increased greatly.Greenhouse gases and other human inputs add to the heat budget of the atmosphere = (radiative forcing)Slide 22Slide 23WILDFIRES: accelerate several cyclesForest fires increase CO2 emissions. Fires are increasing in frequency/severity.How are humans altering the N cycle?Inputs of N into rivers (and then oceans) has increased greatly since 1960.Slide 29PHOSPHORUSHow are humans altering P cycle?Phosphorus concentration controls the trophic structure and productivity of lakes.Slide 33Nutrient-rich fresh water floats over salt water.Oyxgen depletion by great bacterial response to input of organic waste--> anoxic conditions for fish that dieLarge ‘dead zones’ with hypoxic bottom waters.Slide 37Human eutrophication (overproduction of organic matter in aquatic systems) is harmful.Consequences for aquatic systemsSULFURSO4 emissions from copper smelter(Sulfuric) acid drainage from coal mines.pH profoundly affects ecosystems, especially aquatic systems.Slide 44Effects of acid rain on a forest. Why is damage greater on 1 side of mt.? Why haven’t forests recovered when acid rain was lessened?Slide 46Slide 47Lessons from acid rain researchHow do humans affect S cycle?Ozone (O3) + UV radiation2.In upper atmosphere O3 blocks UV radiation CFCs destroy ozone -->creates ‘black hole’--> increase damage to DNA from UV --> skin cancer Treaties ban CFCs, but slow repair of hole…How do our choices leave a FOOTPRINT at higher levels of ecological organization?Our Ecological FootprintOUR Ecological Footprint 1. Live near work; ride bike; minimize car use.2. Buy energy-efficient furnace.3. Programmable thermostat: 50 winter/ 80 summer4. Turn off lights when leave room; unplug appliance5. Eat low on food chain.6. Buy food locally; eliminate transportation energy.7. Buy hybrid car - reduce gas consumption by 1/28. Get ‘on demand’ water heater.9. Winterize house.10. Recycle; pay tax for it.11. Reduce paper/plastic (and ALL) consumption.12. Reuse (and repair) items; don’t use ‘throw- aways’13. Restore: Buy C offset for travel--> plant trees.…For Tuesday•Go to website for Lecture Outline•Read 10 sections in text about ‘Global Change Biology’ •Pay particular attention to Figures•Be ready to explain topic/figures to group/classOur ‘stuff’… or“how humansalter nutrientcycles and deplete naturalresources…”OBJECTIVESHuman Activities Alter Nutrient Cycles Relates to Intersystem Cycles: Pools/Fluxes altered Inputs/Outputs disrupted-->consequences• Water• Carbon• Nitrogen• Phosphorus• Sulfur• OzoneIntersystem cycling: Nutrients gained (input) and lost (output) by an ecosystem Ecosystem 12Input  output Ecosystem 2Input Output Ecosystem 1Ecosystems modeled as linked compartments (box = pool; arrow = flux).Figure 2Nutrient inputs on land from:•Lithosphere (weathering of bedrock and soil)•Atmosphere–Wetfall (in precipitation)–Dryfall (particles)•Hydrosphere•Human ActivitiesNutrient losses (output) on land to:•Atmosphere•Streams and groundwater•Human activities•How do human activities alter output?Plowing of prairies contributed to the creation of the Midwest’s Dust Bowl (1930s).Soil erosion on plowed farmland…about 1% of topsoil is lost each year.Over-grazing leads to loss of vegetation and leads to soil erosion.WATER*Water use greatly exceeds water supplies in many parts of our West.Irrigation can turn desert into productive farmland…But…accumulation of salts in soil that accompanies irrigation can damage crops.Clear-cutting affects hydrology, erosion, nutrient-off…50% of water in the Amazon Basin is internally recycled. Predict how deforestation there might be affecting the local hydrologic (water) cycle and the forest.How are humans altering water cycle? •Depletion from overuse• Fossilized vs. re-chargeable aquifers• Overpopulation--> insufficient local water• Used to produce crops to produce meat• Irrigation --> salt problems •Land-use changes lower local cycling-> drought•Links to other cycles:• Water carries solutes (e.g. N,P,K, H+)• C cycle - link to global warming -->• precipitation changes worldwide• glacial melt --> loss of water sourceCARBON --> Global warmingHuman production of CO2 by burning of fossil fuels has increased greatly.Greenhouse gases and other human inputs add to the heat budget of the atmosphere =(radiative forcing)snow intactsnow removedintactremovedWILDFIRES: accelerate several cyclesForest fires increase CO2 emissions. Fires are increasing in frequency/severity.NH41 3b2a2b3a45 -3 +3iNITROGENHow are humans altering the N cycle?•Nitrogen-fixing crops•Invasive species fix N2•Fossil fuel burning--> nitrous oxide