1. Carbon, Nitrogen and Phosphorus Cycles
How is it possible that life can continue to persist for billions of years even though there is no new energy or matter being added to Earth?

2. Learning Goals/ Success Criteria Learning Targets
I know that matter must be cycled in the environment for life to be sustained
I know that Earth’s four spheres are; the Hydrosphere, the Lithosphere, the Atmosphere, which all combined forms the Biosphere
I know that humans can influence the cycling of matter, which can lead to imbalances that affect the environment
I can describe or draw the water, carbon, phosphorous and nitrogen cycle

3. The Four Spheres of Earth

4. All matter CYCLES through these four spheres!

5. It’s very complicated!!!

6. Let’s keep it “simple” and just focus on C, N, P and H2O cycles

7. The Carbon Cycle

8. Carbon Moves From: Atmosphere to plants
(C02 pulled from air to use in photosynthesis)
Plants to animals
(animals eat plants or other animals)
Plants and animals to soils
(decaying bodies release carbon into the soil)
Living things to atmosphere
(as you exhale, release CO2)

9. Concerns for Humans
CO2 is a greenhouse gas that traps heat in the atmosphere.
Burning fossil fuels has added 5.5 billion tons per year of carbon to the atmosphere (a 30% increase over the past 150 years)
The increased Carbon is causing the planet to become warmer.

10. The Nitrogen Cycle 80% of Nitrogen is in the atomosphere
(it is not in a form that humans can use: needs to be broken down by lightning, fire or bacteria)
Animals get nitrogen to make amino acids by eating plants
(when animals/plants die, decompose and return nitrogen to soil)

11. Concerns for Humans
The use of nitrogen rich fertilizers, causes too much nitrogen to be added to waterways via runoff.
Animal wastes associated with farming add more nitrogen to soil and water.
Burning fossil fuels fixes nitrogen from the air.
High concentrations of nitrogen in the water causes “algae blooms”: toxic to fish and shellfish.

12. The Phosphorus Cycle
No atmosphere connection. Phosphorus added by animal waste, runoff and rock erosion.
(Plants pick up the phosphorus from water; animals eat the plants. Decaying plants and animals and animal wastes return phosphorus to the soil.)

13. Concerns for Humans Phosphorus run off leads to eutrophication
Eutrophication: a process whereby water bodies, such as lakes, estuaries, or slow-moving streams receive excess nutrients that stimulate excessive plant growth (algae and nuisance plants weeds). This enhanced plant growth reduces dissolved oxygen in the water when dead plant material decomposes and can cause other organisms to die.

14. Ecology Photo of the Day

15. What Mr. T’s hopes you’ve learnt
Carbon cycle explains how all life uses energy and how we use fossil fuels as fuel now (stored up energy in bonds from millions of years ago now used to do work today), but global warming is happening
Phosphorous cycle needed for  creation of DNA, cell membranes, and for bone and teeth formation BUT fertilizers and livestock lead to excess phosphorous and eutrophication events
Nitrogen cycle needed for DNA and protein BUT misuse has led to eutrophication events and run-off dead zones

16. Activity of the Day Group 1 – Importance of Carbon on Biosphere
Group 2 – Problems with excess Carbon in the atmosphere
Group 3 – Imp’tance of Nitrogen on Biosphere
Group 4 – How and Why excess Nitrogen is bad for the Biosphere and Hydrosphere
Group 5 – Imp’t of Phosphorous on Biosphere
Group 6 - How and Why excess Phosphorous is bad for the Biosphere and Hydrosphere
USE PADLET and each group will briefly present -