Nutrient CyclesNutrient cycles (= biogeochemical cycles): natural processes that involve the flow of nutrients from the ___________ environment (air, water, soil, rock) to living organisms (_________) & back again.

Nutrient cycles involve _____________ flow of high–quality energy from the sun through the environment & ____________ of elements.

Major Locations (Reservoirs) of Nutrients______________ – involving flows through the hydrosphere, in

the form of liquid water, compounds dissolved in water, & sediments carried by water.

________________ –involving flows through the atmosphere, as gases or airborne particles (particulates).

_________________(lithospheric)–involving flows through the lithosphere (Earth's crust = soil & rock), as solid minerals.

Water CycleMain Processes:evaporation: conversion from liquid to vapor form (surface to

atmosphere).________________: evaporation from leaves of water

extracted from soil by roots & transported through the plant (surface to atmosphere).

transportation in atmosphere: transport as vapor.condensation: conversion of vapor to liquid droplets (clouds).precipitation: movement as rain, sleet, hail, & snow

(atmosphere to surface).______________: movement into soil.______________: downward flow through soil to aquifers.flow in aquifers: below ground flow of water.runoff: surface flow downslope to ocean.

Review with your table partner:List one similarity and one difference between evaporation and transpiration?

Put the following terms in the correct order that they would occur: Percolation, Precipitation, Infiltration.

• Both involve the change of water into __________. • Transpiration occurs from the ________________

______________Evaporation is ____________

Discuss with your table partner:How might deforestation of a tropical rainforest affect the rainfall in a region? (What process would be changed and how could this affect rainfall?)With a large amount of surface area of leaves, _____________ can return a lot of water vapor to the atmosphere. Scientists are finding that this can ____________ rainfall.

Water CycleRole of Water: Necessary for life

• terrestrial ecosystems – major factor determining _______________ of organisms

• aquatic ecosystems – literally _________ that surrounds & serves as environment of aquatic organisms

• flows of water are major means material & ______ transport• water is critical for human activities – agriculture, industry, &

municipal useHuman Influences:

• withdraw large quantities of fresh water – water diversion, _________________depletion, wetland drainage

• clear vegetation – increase ______________, decrease infiltration & groundwater recharge, increase flooding & soil _______________

• modify water quality – add nutrients (P, N…) and/or _______________

• Climate Change: more _____________ in water cycle system

Carbon CycleRole of Carbon:

building block of ___________ molecules(carbohydrates, fats, proteins, & nucleic acid) – essential to life

currency of energy ____________ – chemical energy for life stored as bonds in organic compounds

carbon dioxide (CO2) is a ______________ gas – traps heat near Earth's surface & plays a key role as "nature's thermostat“

Carbon Cycle Processesphotosynthesis ( = carbon __________)

moves C from atmosphere to organic molecules (C,H,O compounds) in organisms;

movement through food web: C movement in organic form from organism to organism;

movement between ___________ and atmosphere: uptake and release from _____________

aerobic _________________: organic molecules broken down to release CO2back to atmosphere;

Carbon Cycle Processes Cont.movement to sediments and rock: C forms CaCO3 through _____________ processes (shell formation in plankton and larger marine organisms); enters sediments after organisms die; and eventually becomes rock (______________).Fossil fuel formation:organic molecules are buried, compressed, and heated to form _______________ (oil, natural gas), and elemental carbon (coal)_________________: organic molecules broken down by burning to release CO2 back to atmosphere;

Limestone

Carbon Cycle• Photosynthesis, Respiration, and decay happen in both land and ocean

ecosystems• Plants perform both photosynthesis and ____________• Combustion inputs to the atmosphere include burning of fossil fuels,

____________(not shown),

• Volcanoes erupt it

(Photosynthesis)

Rock formation

Fossil fuel formation

(Combustion)

Carbon CycleIdentify sources and sinks for atmospheric carbon:

(Photosynthesis)

Rock formation

Fossil fuel formation

(Combustion)

Sources:(Puts C into Atmosphere)

•

•

•

•

•

Sinks:(Removes C fromAtmosphere)

•

•

• Increased ______________ (burning of fossil fuels (organic carbon compounds)

• Increased ______________ - reduces rate of photosynthesis

Human Influences to Carbon Cycle:

Nitrogen Cycle• Nitrogen (N2) is the most common gas

in the atmosphere (______).• Nitrogen is needed by all living things.

N is part of ________ and protein.• However, most organisms cannot

utilize N2 because ______________ makes it non-reactive

• ___________ Nutrient in many ecosystems: typically addition of N in fertilizers leads to increased productivity

Nitrogen Cycle Processesnitrogen ___________: conversion of N2 (nitrogen gas) to NH4

+ (ammonium),

Performed by bacteria & blue-green algae (anaerobic),

e.g., Rhizobium in nodules on roots of legumes;

N2 is also fixed by lightning

_______________: conversion of NH4+

to NO2- (nitrite) and to NO3

-(nitrate) by microbes; (Oxidation process)

_________ of NO3 or NH4+ by plants,

forms proteins and other N-containing organic compounds, enters food chain;

Nitrogen Cycle Processes Cont._________________: decomposers return nitrate to NH4

+

______________________:• Conversion of NH4

+ to N2by combustion or microbes.

• Conversion of NOx to N2by _____________ (reduction process)

• N2 returns to atmosphere

Nitrogen Cycle

Fig. 5–6

Nitrification

Denitri-fication

Ammonification

Review with your table partner:Name a form of nitrogen that can’t be used by most organisms.

Name a form of nitrogen that can be used by most organisms.

Why do legume plants (bean family) have an advantage in getting enough of the usable nitrogen compounds they need?

Continue to next slide

What three types of bacteria are involved in the nitrogen cycle? Which are involved in producing usable nitrogen compounds and which are involved in cycling nitrogen compounds back to the atmosphere?

Inorganic FertilizersDuring WWI, _____________developed process to convert atmospheric nitrogen into _____________ to make inorganic nitrate fertilizers.(Process happens at high temperatures, whichconsumes a lot of _________energy.)Revolutionized farming:increasing yields. Part of the _________ REVOLUTION

Human Influences on the Nitrogen Cycle• emit nitric oxide (NO), which

leads to ______________ and acid rain;

• emit nitrous oxide into the atmosphere – nitrous oxide (N2O) is a potent ____________ gas & also depletes ozone in stratosphere

• Use of nitrogen fertilizers which leads to ________________ of water bodies

Beijing

• Can be limiting factor for growth• No __________________ component of cycle

Phosphorous Cycle

• Always occurs in the form ____________(PO4)

• Released from rocks by ___________ (slow process)

• Needed by all living things for:DNA, ATP, Phospholipids

Mining large quantities for fertilizers and ____________Cutting down forests reduces available phosphateAdd excess phosphate to aquatic systems from livestock _____________, runoff from farmland, and _____________ discharges

Human Influences of Phosphorous Cycle:

Bird droppings are high in Phosphorous

Sulfur Cycle• Sulfur is a

common element and S compounds are found in rocks, soil and fossil fuels (esp. ____)

• Sulfur is emitted to atmosphere through ___________ and fossil fuel burning

• Sulfur combines with water in the atmosphere to form _______________(H2SO4) and returns to earth as acid deposition (i.e. acid rain)

Sulfur Cycle• Sulfur is converted to sulfate

(SO42-) in soil by __________

• Plants uptake _________ form only (used in 2 amino acids)

Sulfur CycleHuman Influences:• _______________burning

(especially coal)• ___________ (refining of

metal ores)—releases SOxto atmosphere

• Sulfur compounds in the atmosphere cause ______ _____ (Sulfuric acid: H2SO4)

Smelting

Coal Plant

Acid Rain Damage

Where do plants get their nutrients?

Nutrient Major Source Reservoir

How plants uptakeNutrient

WaterCarbon

(current and fossil) Most is in the oceans

NitrogenSulfurPhosphorous

Important Nutrients for Plants