•Carbon, Nitrogen and Phosphorus Cycles – notes and videos

SHORT-TERM AND LONG-TERM CYCLES

CARBON CYCLE

CARBON CYCLE

•Carbon is an essential component of proteins, fats, and carbohydrates, which make up all organisms

CARBON: GOOD OR BAD?

How carbon HELPS the planet• Element in living things • Plants need carbon for photosynthesis• Carbon keeps the planet warm and livable• Some of the things we use everyday contain carbon• Ex.

CARBON: GOOD OR BAD?

How carbon HURTS the planet• Too much carbon dioxide in the atmosphere changes the climate• Too much carbon dioxide dissolving in the ocean makes it more acidic• Chlorofluorocarbons deplete the ozone

THE SHORT-TERM CARBON CYCLE

1.CO₂ in atmosphere converted to carbohydrates during photosynthesis by producers.

2.Consumers eat producers3.Consumers and producers

release CO₂ into atmosphere.

SHORT-TERM CARBON CYCLE

LONG-TERM CARBON CYCLE

• 1. Limestone: • Carbon is stored in bones and shells•Do not decompose.•Over millions of years form limestone deposits (carbon reservoir)

LONG-TERM CARBON CYCLE

• 2. Coal:• Carbon in plants and animals is released into soil •Over millions of year soil can form deposits of coal or natural gas (fossil fuels)

HUMANS AND THE CARBON CYCLE•Humans put CO₂ into the atmosphere by:•Burning fossil fuels•Burning wood/forest fires•Making cement• Increased CO₂ in the atmosphere leads to:• Traps heat in our atmosphere and the Earth slowly heats up…global warming.

NITROGEN CYCLE

•Why? - Need nitrogen to build proteins which build new cells•Where? – Nitrogen makes up 78% of the atmosphere

NITROGEN CYCLE

•How? – Nitrogen-fixing bacteria: alter atmospheric nitrogen into chemical compounds

THE NITROGEN CYCLE

•Nitrogen-fixing bacteria• Live within nodules on roots of plants called legumes (i.e. beans, peas, clover).• Produce nitrates.•Nitrates are released into the soil.• Plants get these nitrates, animals that eat the plants get the nitrates.

PHOSPHORUS

• Is an element•Makes up cells of living organisms•Example: Forms bones and teeth

WHERE IS PHOSPHORUS FOUND?

•NOT in the atmosphere!•Found in rocks - which enters the soil when rocks erode