Enviromental study notes

Environmental Biotechnology
Biogeochemical Cycling
The Carbon Cycle

Why is carbon so important.

BIOT6008 Environmental Biotechnology

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Environmental Biotechnology
Sources of Carbon
The Earth’s Crust: The largest amount of carbon on Earth is stored in sedimentary rocks.

Oceans: most in the form of dissolved inorganic carbon stored at great depths. A much smaller amount of carbon is located near the surface. Atmosphere: Mostly in the form of CO2. This carbon is of vital importance because of its influence on the greenhouse effect.
Terrestrial Ecosystems: Contain carbon in the form of plants, animals, soils and microorganisms (bacteria and fungi). Unlike the
Earth’s crust and oceans, most of the carbon in terrestrial ecosystems exists in organic forms.
BIOT6008 Environmental Biotechnology

Lecture 3

Environmental Biotechnology

BIOT6008 Environmental Biotechnology

Lecture 3

Environmental Biotechnology
• Plants use carbon dioxide from the atmosphere and use it to make food –— photosynthesis. • The carbon becomes part of the plant
(stored food).
• When organisms eat plants, they take in the carbon and some of it becomes part of their own bodies.

• When plants and animals die, most of their bodies are decomposed and carbon atoms are returned to the atmosphere.
• Some are not decomposed fully and end up in deposits underground (oil, coal, etc.).
• Carbon in rocks and underground deposits is released very slowly into the atmosphere.
BIOT6008 Environmental Biotechnology

Lecture 3

Environmental Biotechnology
Release of carbon into the atmosphere

BIOT6008 Environmental Biotechnology

Lecture 3

Environmental Biotechnology
Removal of carbon from the atmosphere

BIOT6008 Environmental Biotechnology

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Environmental Biotechnology
Human Impact – Burning of Fossil Fuels

BIOT6008 Environmental Biotechnology

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Environmental Biotechnology

Greenhouse gasses in the atmosphere act like the glass in a greenhouse or car – good thing.

BIOT6008 Environmental Biotechnology

Lecture 3

Environmental Biotechnology
Major Greenhouse Gases

Water vapor : does much to keep planet warm. We have no control over water vapor. CO2 is the most significant greenhouse gas. Levels increasing because of fossil fuel burning.
Other Greenhouse Gases
Methane: from wetlands, ruminants and commercial production.
Nitrogen oxides (NOx or NxO) - formed during combustion from N2 that’s in air.
Ozone - formed from lightning, electrical arcs, and a reaction of gas vapors and sunlight. BIOT6008 Environmental Biotechnology

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Environmental Biotechnology

• The Greenhouse Effect - radiative energy leaving a planetary surface is absorbed by some atmospheric gases, called Greenhouse Gases.
• After these gases absorbs the infrared radiation, they emit this energy which subsequently warm the earth’s surface.
• Natural phenomenon but enhanced by human activities.
BIOT6008 Environmental Biotechnology

Lecture 3

Environmental Biotechnology
Phosphorous

Sulfur

BIOT6008 Environmental Biotechnology

Lecture 3

Environmental Biotechnology
Phosphorous Cycle
The largest reservoir of phosphorus is in sedimentary rock.
When it rains, phosphates are removed from the rocks and are distributed throughout both soils and water.

Plants take up the phosphate ions from the soil moves from plants to animals.

BIOT6008 Environmental Biotechnology

Lecture 3

Environmental Biotechnology
Sulfur Cycle

Weathering of rocks releases stored sulfur (contact with air sulfate.
Sulfate is taken up by plants and microorganisms and is converted into organic forms moves through the food chain.
Decomposition of plants and animals release sulfate.

Natural sources - volcanic eruptions, the breakdown of organic matter in swamps and tidal flats, and the evaporation of water.

Sulfur eventually settles back into the Earth or comes down within rainfall BIOT6008 Environmental Biotechnology

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