Nutrient CyclesNutrient Cycles & how Humans impact & how Humans impact

nutrient cyclingnutrient cycling

Bio1Bio1

Where do energy & Where do energy & nutrients come from?nutrients come from?

What are nutrients? What else do organisms What are nutrients? What else do organisms need to survive and grow?need to survive and grow?

Organisms need Organisms need ______________, , ____________, and a , and a number of key elements like number of key elements like ______________, , ______________, , ________________, and , and __________________..

How do organisms How do organisms getget all of the above? all of the above?

EnergyEnergy waterwatercarboncarbon

oxygenoxygen hydrogenhydrogennitrogennitrogen

Energy Energy FlowsFlows, Nutrients , Nutrients CycleCycle

Energy enters the biosphere continually from Energy enters the biosphere continually from _________._________.

However, all the water and matter (the stuff) However, all the water and matter (the stuff) organisms need to survive already exists in the organisms need to survive already exists in the biosphere -- it simply gets ______ over and over. biosphere -- it simply gets ______ over and over. If the water & matter we need to live wasn’t If the water & matter we need to live wasn’t ________, we would eventually run out. We have ________, we would eventually run out. We have no other source of these things entering the no other source of these things entering the biosphere.biosphere.

So the recycling of matter is very important. So the recycling of matter is very important. HowHow does matter get recycled? A variety of ways…does matter get recycled? A variety of ways…

the SUNthe SUN

reusedreused

recycledrecycled

The Water CycleThe Water Cycle

#’s in parentheses indicate amount of water as billion billion (10#’s in parentheses indicate amount of water as billion billion (101818) grams/yr) grams/yr

Atmospheric water vapor (13)

Water content of oceans (1,380,000)

Water content of sedimentary rocks near earth’s surface (210,000)

condensation

condensation

Water Cycles Through the Biosphere…Water Cycles Through the Biosphere…

• 1a: Liquid water in rivers, lakes & oceans 1a: Liquid water in rivers, lakes & oceans evaporatesevaporates as it as it turns into water vapor (gas).turns into water vapor (gas).

• 1b: Water vapor is also released from plants during 1b: Water vapor is also released from plants during transpiration.transpiration.

• 2: Water vapor in atmosphere 2: Water vapor in atmosphere condensescondenses to form clouds to form clouds (liquid again).(liquid again).

• 3: Water returns to earth during 3: Water returns to earth during precipitation.precipitation.• 4: Precipitation over land may 4: Precipitation over land may runoffrunoff into bodies of water or into bodies of water or

infiltrateinfiltrate the soil and the soil and percolatepercolate into the ground to become into the ground to become groundwatergroundwater (which is stored in (which is stored in aquifersaquifers).).

• 5: Water in ground is absorbed by 5: Water in ground is absorbed by plantsplants through roots. through roots. Surface water & groundwater flows to ocean.Surface water & groundwater flows to ocean.

• Now go back to the beginning…Now go back to the beginning…

Water Cycle is Affected Water Cycle is Affected by Human Actionby Human Action

• Clearing vegetationClearing vegetation from land for agriculture, mining, from land for agriculture, mining, road & building construction often road & building construction often increases runoffincreases runoff and and can can reduce infiltrationreduce infiltration that recharges underground water that recharges underground water suppliessupplies

• Use of groundwater for Use of groundwater for irrigationirrigation increases evaporation increases evaporation over land and over land and depletes groundwater suppliesdepletes groundwater supplies ( (aquifer aquifer depletiondepletion).).

Ex) Ex) Ogallala aquiferOgallala aquifer (world’s largest known aquifer) (world’s largest known aquifer)– Found under parts of WY, SD, NE, KA, CO, OK, NM, TXFound under parts of WY, SD, NE, KA, CO, OK, NM, TX– Used to irrigate vast areas of arid high-plains prairie into one of Used to irrigate vast areas of arid high-plains prairie into one of

largest, most-productive agricultural regions in US (produces 1/5 largest, most-productive agricultural regions in US (produces 1/5 of US agricultural output)of US agricultural output)

– In some areas, water is being pumped out 8-10 times faster than In some areas, water is being pumped out 8-10 times faster than the (slow) natural recharge ratethe (slow) natural recharge rate

Ogallala Aquifer

Carbon CycleCarbon Cycle

DecomposersDecomposers (bacteria in soil (bacteria in soil

& others)& others)Dead Plants Dead Plants and Animalsand Animals

Carbon: From Air to OrganismCarbon: From Air to Organism

• Carbon dioxide (COCarbon dioxide (CO22) in air is used by ) in air is used by

______ during _____________.______ during _____________.

• Carbon moves from COCarbon moves from CO22 in atmosphere in atmosphere

into sugars in plants.into sugars in plants.

plantsplants photosynthesisphotosynthesis

COCO22 + H + H22O + sunlight -->O + sunlight --> CC66HH1212OO66 + O + O22

Carbon: From Organism to AirCarbon: From Organism to Air

• Organic compounds (like COrganic compounds (like C66HH1212OO66) in plants, ) in plants,

animals and microbes are used (“burned”) as an animals and microbes are used (“burned”) as an energy source. This process, which organisms energy source. This process, which organisms carry out to release energy from their food, is carry out to release energy from their food, is called __________________.called __________________.

• As part of this process, waste ____ is released.As part of this process, waste ____ is released.

cellular respirationcellular respiration

CC66HH1212OO66 + O + O2 2 -->-->

COCO22

COCO2 2 + H+ H22O + ATP O + ATP (chemical energy)(chemical energy)

Other Ways Carbon Circulates Other Ways Carbon Circulates (including Human Impact)(including Human Impact)

• Burning of forests or other organic matter Burning of forests or other organic matter releases CO and COreleases CO and CO22 into the atmosphere. into the atmosphere.

• Burning of fossil fuels (_____, ___, Burning of fossil fuels (_____, ___, __________) for industry, transportation, and __________) for industry, transportation, and municipal energy production also releases municipal energy production also releases CO and COCO and CO22..

• Anaerobic bacteria (like those in mammalian Anaerobic bacteria (like those in mammalian digestive systems) produce _____________ digestive systems) produce _____________ (CH(CH44) as a byproduct of their metabolism.) as a byproduct of their metabolism.

coalcoal oiloilpetroleumpetroleum

methane gasmethane gas

http://www.rspbliverpool.org.uk/joint%20coach%20trips.htm

Carbon CycleCarbon Cycle

Decomposers (bacteria in soil

& others)Dead Plants and Animals

Dead Plants & Animals

Decomposers

Ammonia (NH3)

Ammonia (NH3) taken

in by legumes

Nitrogen CycleNitrogen Cycle

Nitrogen: From Air to SoilNitrogen: From Air to Soil• Why do organisms need nitrogen?Why do organisms need nitrogen?• Molecular nitrogen gas (NMolecular nitrogen gas (N22) in atmosphere ) in atmosphere

not directly usable by most organismsnot directly usable by most organisms• 1: ________________ bacteria in 1: ________________ bacteria in legume legume

root nodulesroot nodules and in and in soilsoil “fix” nitrogen, “fix” nitrogen, converting Nconverting N22 into ammonia (NH into ammonia (NH33))

Nitrogen-fixingNitrogen-fixing

Clover root nodules

inhabited by Rhizobium

bacteria

Nitrogen: From Soil to PlantNitrogen: From Soil to Plant• 2: Some 2: Some ammoniaammonia in soil is used directly by in soil is used directly by

plants (absorbed through roots) to make plants (absorbed through roots) to make _____________, but many plants still cannot _____________, but many plants still cannot use this form of nitrogen.use this form of nitrogen.

• 3: Most ammonia in soil is converted to 3: Most ammonia in soil is converted to nitritenitrite (NO(NO22

--) and then ) and then nitratenitrate (NO (NO33--) by _________ ) by _________

bacteria.bacteria.

• 4: 4: NitrateNitrate (NO (NO33--) is the form of nitrogen that ) is the form of nitrogen that

most plants most plants cancan absorb (through roots) and absorb (through roots) and use to make _____________.use to make _____________.

plant proteinsplant proteins

nitrifyingnitrifying

plant proteinsplant proteins

Nitrogen: From Plant to Nitrogen: From Plant to Animal to Soil Again!Animal to Soil Again!

• 5: Animals get their nitrogen by 5: Animals get their nitrogen by ____________________________ .____________________________ .

• 6: Plants & animals die, are broken 6: Plants & animals die, are broken down by _____________ bacteria, down by _____________ bacteria, producing ________________ in the producing ________________ in the soil again.soil again.

• Guess what can happen to this _____ Guess what can happen to this _____ now?now?

eating plants and other animalseating plants and other animals

decomposingdecomposingammonia (NHammonia (NH33))

NHNH33

• • can be assimilated (taken in & used) by Plants to make Proteinscan be assimilated (taken in & used) by Plants to make Proteins

• • can be used by Nitrifying Bacteria & converted to Nitratecan be used by Nitrifying Bacteria & converted to Nitrate

Nitrogen: From Soil to Air againNitrogen: From Soil to Air again

• 7: __________ bacteria in soil convert 7: __________ bacteria in soil convert nitrites & nitrates to molecular nitrogen nitrites & nitrates to molecular nitrogen gasgas– This is especially true in low OThis is especially true in low O22 conditions conditions

• Implications for farmers?Implications for farmers?

DenitrifyingDenitrifying

Other Factors in the Nitrogen CycleOther Factors in the Nitrogen Cycle

• Nitrogen fixation also Nitrogen fixation also occurs in some amount occurs in some amount due to lightening strikesdue to lightening strikes

• Nitrogen compounds also Nitrogen compounds also released into atmosphere released into atmosphere by volcanoesby volcanoes

Nitrogen CycleNitrogen Cycle

Dead Plants & Animals

Decomposers

Ammonia (NH3)

Human Effects on Nitrogen CycleHuman Effects on Nitrogen Cycle

• Nitrogen oxides emitted from the combustion Nitrogen oxides emitted from the combustion of fossil fuels (from industry, transportation)of fossil fuels (from industry, transportation)

• Excess nitrogen compounds released into Excess nitrogen compounds released into environment via improper disposal of livestock environment via improper disposal of livestock waste/manure (waste/manure (think pig poopthink pig poop) or even ) or even untreated human sewageuntreated human sewage

• Nitrate and phosphate-rich fertilizers used Nitrate and phosphate-rich fertilizers used heavily in agriculture ==> can lead to heavily in agriculture ==> can lead to ______________ (enrichment of a previously ______________ (enrichment of a previously limiting nutrient) of freshwater ecosystems due limiting nutrient) of freshwater ecosystems due to fertilizer-contaminated runoff from farmland. to fertilizer-contaminated runoff from farmland. What’s so bad about this? Let’s see… What’s so bad about this? Let’s see…

eutrophicationeutrophication

Eutrophication as a process:Eutrophication as a process:

Eutrophication Effects Eutrophication Effects (in pictures)(in pictures)

Also check out: http://en.wikipedia.org/wiki/Eutrophication

Phosphorus CyclePhosphorus Cycle