OUR Ecological Footprint - 151. Live near work; Ride bike; minimize car use.2. Buy energy-efficient furnace.3. Programmable thermostat: winter/summer4. Turn off lights when leave room; unplug appliance5. Eat lower on food chain.6. Buy food locally; eliminate transportation energy.7. Buy hybrid car - reduce gas consumption by 1/28. Recycle; pay tax for it.9. Reduce paper/plastic (and ALL) consumption.10. Reuse (and repair) items; don’t use ‘throw- aways’11. Get ‘on demand’ water heater.12. Winterize house.13. Buy C offset for travel.

…for Tuesday

Go to: www.worldchanging.com

Select one article, read it, print first page (only) and bring to lecture.

1 Stuff 5 Business

2 Shelter 6 Politics

3 Cities 7 Planet

4 Community 8 Any of 1-7

OBJECTIVES

Human Activities Alter Nutrient Cycles Relates to Intersystem Cycles:

Inputs/Outputs disrupted-->consequences

• Water

• Carbon

• Nitrogen

• Ozone

• Phosphorus

• Sulfur

Intersystem cycling: Nutrients gained (input) and lost (output) by an ecosystem

Ecosystem 12

Input output

Ecosystem 2

Input

Output

Ecosystem 1

Intersystem cycling

-->Input from waterflow

Nutrient inputs on land from:

• Lithosphere (weathering of bedrock and

soil)

• Atmosphere

– Wetfall (in precipitation)

– Dryfall (particles)

• Hydrosphere

• Human Activities

Nutrient losses (output) on land to:

• Atmosphere

• Streams and groundwater

• How do human activities alter output?

WATER

Global BGC cycles: Water cycle: a physical model

50% of water in the Amazon Basin is internally recycled. Predict how deforestation there might be affecting the hydrologic (water) cycle and the forest.

*

Figure 3

CARBON

***Carbon cycle: What are 2 new fluxes due to human activities? What pools are being altered?

The missing C sink

Figure 6

snow intact snow removed

intactremoved

WILDFIRES

NITROGEN

How are humans altering the N cycle?• Nitrogen-fixing crops• Fossil fuel burning• Nitrogen fertilizer• Animal feed lots + manure • Invasive species fix N2• Consequences• greenhouse gases• nitrogen saturation• runoff - aquatic systems + water supply• biodiversity and species mix

OZONE

Ozone (O3) + UV radiation

1. at surface

• O2 with NO2 with light --> O3

• NO2 from burning gas in cars

• Ozone = oxidant of organic molecules

• SOYFACE: elevated O3 lowers crop

productivity

2. Ozone in upper atmosphere blocks UV CFCs and creates ‘black hole’

PHOSPHORUS

Phosphorus concentration controls the

trophic structure and productivity of lakes.

CNP

CN

• Human activities affect input from land to

water

• runoff/seepage into groundwater/aquifers

• agriculture land, especially NPK

• animal feedlots, especially N

• sewage input, C, N

Human eutrophication (overproduction of organic matter in aquatic systems) is harmful.

• Added nutrients stimulate algal GPP, BUT• • Too much overwhelms intrasystem regeneration• • Increase in organic matter; increased sediments• • Energy flows to bacteria, not higher trophic level• • Increase in decomposition + use of oxygen• ---> depletes oxygen• ---> kills aerobes, including fish

Consequences for aquatic systems

• change freshwater aquatic communities

• create ‘dead zones’ in oceans

• lower quality of drinking water

Dead zones around earth

SULFUR

SO4 emissions from copper smelter

(Sulfuric) acid drainage from coal mines.

pH profoundly affects ecosystems, especially aquatic systems.

Rise in pH with decreased SO4 emissions

Acid rain from coal-burning industries affects forest growth.Slow recovery from its effects…

Effects 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?

Lessons from acid rain research

The hierarchical nature and processes of different levels of ecological systems:

Our Ecological Footprint

• How do our life style choices at the

individual level impact higher levels of

ecological organization?

• How does a choice impact energy flow

and cycling of matter?

H2O C N ozone P S