Review for Nutrient Cycles and Climate Change

Leeward and Windward side of a mountain• Describe how much rain an area gets– Windward- side facing the wind, more moisture– Leeward- drier side, usually results in a rain

shadow desert

El NinoEl Niño events (also ENSO) occur every 2-7 years, lasting for 1,1 1/2years.East-west trade winds weaken and eastern Pacific waters warm! Tropical rainfall shifts from Indonesia to South America. Floods in Peru; Droughts and fires in Indonesia and Australia. Upwelling at South American coast-line is suppressed. Natural.

Carbon

• Reservoirs– atmosphere– Ocean– Rocks– Soil – Fossil fuels

• Assimilation– Photosynthesis

Cyclingpredationweatheringerosion

• Loss– Respiration– Decomposition– Forest fires– Burning of fossil fuels– Volcanic eruptions• Can contribute to cooling of the atmosphere due to

blocking the suns rays

Nitrogen

• Reservoirs: – air, – soil, – ocean.

• Assimilation:– nitrogen fixation, – lightning, – industry (50%).

• Cycling: – internal– erosion and runoff – sea spray– Usually plants first.

• Ruminants have nitrogen-fixing bacteria in their stomachs that prove50% of N.

• Loss– Denitrification– Marine sedimentation

Phosphorus

• Reservoir– Phosphates of Ca, K, Mg, Fe– Found in bat guanpCycling

to ocean (soluble form or suspension)ocean feeding birds (guano deposits)

Upwellings (winds push surface water away from land, exposing deeper, nutrient rich water)Uplifting of sedimentary rock

• Loss– Ocean sedimentationLimiting factors

insoluble, hard to break down,falls into the sedimentary cycledoesn’t have a gaseous statemoves through the environment very slowly

Sulfur

• Reservoirs– Rock– SoilAvailable reservoirsairbelow groundAssimilationRoot uptakeGaseous uptake

• Cycling– Litter fall (to ground)– Root leakage

Lossto streamsto atmosphere

Human contributionburning coal and oilsmelting ore

Temperate shrub landChaparral

• Found– Mediterranean– Southern California– Chile– South AfricaClimate

if wetter than usual fires result

Climate change

• Mean global temperature increased 0.5◦C• Positive feedback– positive feedback loop or mechanism is when an

action causes a reaction• the reaction causes more of the action• which in turn causes more reaction, and so forth.

• One of the positive feedback mechanisms already affecting global warming is due to the fact that when the atmosphere is warm– it holds more water vapor, which is considered to be a

greenhouse gas. – As more water vapor is held in the atmosphere, the

temperature increases due to its influence– the increase in temperature allows even more water vapor

to be held in the atmosphere.

• Example– Melting of artic ice• Adds water vapor

Greenhouse Gases

Carbon Dioxide

• Constitutes 76% of the greenhouse gases• Source– Respiration– Burning fossil fuels– Deforest planet

Methane

• Constitutes 13% of the greenhouse gases• Sources– Byproduct of anaerobic respiration of bacteria• Animal belches• Animal waste