biogeochemical cycles. 3 fundamental laws of nature conservation of matter 1st law of thermodynamics...

Biogeochemical Cycles

3 Fundamental Laws of Nature

• Conservation of Matter

• 1st Law of Thermodynamics(Conservation of Energy)

• 2nd Law of Thermodynamics(Entropy)

Earth:Matter does not come and

go

Earth is aClosedSystem

to Matter

Biogeochemical Cycles:Reservoirs & Pathways

Atmosphere

HydrosphereLithosphere

Biosphere

Some Major Cycles of Matter

•Water Cycle•Rock Cycle•Chemical Cycles

•Carbon•Nitrogen•Phosphorous•Sulfur

Carbon Cycle

Atmosphere

HydrosphereLithosphere

Biosphere

Carbon Cycle: Reservoirs

Atmosphere

HydrosphereLithosphere

Biosphere

1x(= 7.3x1017 grams

carbon)

3x

55x35,000x

Carbon Cycle

Atmosphere

HydrosphereLithosphere

Biosphere

Photosynthesis

Respiration& Decay

Carbon Cycle

Atmosphere

HydrosphereLithosphere

Biosphere

Photosynthesis

Respiration& Decay

Burial &Lithification

Weathering& Volcanism

Dissolution

PhotosynthesisBurial &Lithification

Exsolution

Carbon Cycle

Atmosphere

HydrosphereLithosphere

Biosphere

HumanImpacts

Burning fossil fuels:Increased combustion

Deforestation:Decrease Photosynthesis

Increase Respiration

Net Effect:Increase in Carbonin Atmosphere

Atmospheric Carbon Dioxide

northernsummer

northernwinter

Nitrogen Cycle

Atmosphere

HydrosphereLithosphere

Biosphere

Nitrogen fixation:• bacteria• lightning

Waste &Decomposition

Denitification:bacteria

Erosion

Absorption

Nitrogen-Fixing

Bacteria in Root

Nodules

Nitrogen Cycle

Atmosphere

HydrosphereLithosphere

Biosphere

Nitrogen fixation:• industrial (fertilizer)

• combustion

Increased Erosion

HumanImpacts

Net Effect:Increase in Nitrogenin water & soil

Phosphorous Cycle

Atmosphere

HydrosphereLithosphere

Biosphere

Never enters the atmosphere

Waste &Decomposition

Weathering & Erosion

Absorption

SedimentationAbsorption

Phosphorous Cycle

HydrosphereLithosphere

Biosphere

Mining, use (fertilizer, detergent, etc.)& increased runoff

HumanImpacts

Net Effect:Increase in phosphorous in water &“algal blooms”; Depletion in soils

More Phos. for organisms

Eutrophication

Impact:Red Tide

Sulfur Cycle

Atmosphere

Hydrosphere Lithosphere

Biosphere

Volcanoes& Weathering

Waste &Decomposition

Deep Sea Vents

Absorption

Sedimentation

Absorption

Precipitation

“Evaporation” Weathering

BacteriaRelease

BacteriaAbsorption

Sulfur Cycle

Atmosphere

Hydrosphere Lithosphere

Biosphere

BurningFossil Fuels

Precipitation”Acid Rain

HumanImpacts

Net Effect:Increase in atmosphere (health effects) and acid rain

What is the ultimate interface of all 4 reservoirs

for these cycles?

Soil