week 11 nutrient cycles
DESCRIPTION
Carbon and Global WarmingNitrogen Cycle and FertilisersTRANSCRIPT
Nutrient CyclesNutrient CyclesNutrient Cycling
Carbon CycleGlobal WarmingNitrogen Cycle
Nutrient CyclesNutrient Cycles
95% of an organism is made up of only six elements:
Carbon – from CO2 to all organic molecules
Oxygen – from CO2 to all organic molecules
Hydrogen – from H2O to all organic molecules
Nitrogen – from nitrates to all proteins
Phosphorous – phosphates to proteins
Sulphur – sulphates to proteins
Nutrient CyclesNutrient Cycles
95% of an organism is made up of only six elements:
Carbon – from CO2 to all organic molecules
Oxygen – from CO2 to all organic molecules
Hydrogen – from H2O to all organic molecules
Nitrogen – from nitrates to all proteins
Phosphorous – phosphates to proteins
Sulphur – sulphates to proteins(Photosynthesis)
Nutrient CyclesNutrient Cycles
95% of a living organism is made up of only six elements:
Carbon – from CO2 to all organic molecules
Oxygen – from CO2 to all organic molecules
Hydrogen – from H2O to all organic molecules
Nitrogen – from nitrates to all proteins
Phosphorous – phosphates to proteins
Sulphur – sulphates to proteins
(absorbed from soil by roots of plants)
Nutrients in air soil and water
Producers
consumers
decomposers
photosynthesis
feeding
decay
respiration and excretion
feeding
Unavailable organic nutrients coal, oil, peat
Unavailable inorganic nutrients, mineral in rocks
fossilisation
burning erosion
The Carbon CycleThe Carbon Cycle
What is a carbon sink?
The Carbon CycleThe Carbon Cycle
burning
respiration
photosynthesis
Global Warming and the Greenhouse EffectGlobal Warming and the Greenhouse Effect
The Greenhouse EffectThe Greenhouse Effect
G.H. gases don’t absorb visible wavelengths of light
What would reflect solar radiation?
What form does the energy become when absorbed by the Earth?
G.H. gases can absorb and re-emit infra red radiation
Global DimmingGlobal Dimming
The Effects of Global WarmingThe Effects of Global Warming
Is the conclusion that the Earth’s global temperature is increasing valid?
Can you criticise the conclusion?
Is this evidence that humans are the cause?
The Effects of Global WarmingThe Effects of Global Warming
Is this evidence that humans cause global warming?
Any criticisms?
Global Warming and Crop YieldsGlobal Warming and Crop Yields
Why are food prices predicted to increase due to global warming?
How will increased CO2 effect crop yields?How will increased temperature effect crop yields?So what’s the problem….?
Global Warming and Crop Yields: RiceGlobal Warming and Crop Yields: Rice
Maximum
temperature
Minimum temperature
Light Intensity
How Science Works:1.Which variable would you control?2.Can you explain why you need to control each variable?3.What would you do if you couldn’t control a particular variable?
Global Warming and Crop Yields: RiceGlobal Warming and Crop Yields: Rice
Is there a correlation?
What is the relationship
between yield and minimum
temperature?
What is the relationship
between yield and light
intensity?
Global Warming and Crop Yields: RiceGlobal Warming and Crop Yields: Rice
What has the biggest effect on yield?Which factors will change due to global warming?How can we explain this effect?
Global Warming and MigrationGlobal Warming and MigrationWhat will happen to these biomes as the global temperature increases?
How will organisms respond?
Describe this in terms of niches.
Global Warming and MigrationGlobal Warming and Migration
Global Warming and Crop PestsGlobal Warming and Crop Pests
How will global warming effect insect pests?
Why will new pests be able to survive in the UK?
Crop yields will decrease unless…
How will global warming change our farming practices?
Its all about the bacteria!
Its all about the bacteria!
Nutrients in air soil and water
Producers
consumers
decomposers
photosynthesis
feeding
decay
respiration and excretion
feeding
Unavailable organic nutrients coal, oil, peat
Unavailable inorganic nutrients, mineral in rocks
fossilisation
burning erosion
The Nitrogen CycleThe Nitrogen Cycle
Why do living organisms need nitrogen?
What is the largest nitrogen sink on the planet?
What is the problem with N2 gas as a source of nitrogen?
The Nitrogen CycleThe Nitrogen Cycle
Nitrogen-fixing bacteria in root nodules.
Nitrogen-fixing bacteria
The Nitrogen CycleThe Nitrogen Cycle
Nitrogen Fixing Bacteria
“Free living” in soil: Azobacter, Clostridium
Mutualism in plants: Rhizobium
In aquatic systems: Cyanobacteria
Lightning
Provides energy needed to break N2 bonds
Produces Nitric Acid
Dissolves in rain, adding nitrate ions to soil
Nitrogen CycleNitrogen Cycle
Rhizobium and Leguminous Plants:
Invade plant through root hairs
Live in specialised root nodules
Nitrogen CycleNitrogen Cycle
1) Plant releases chemicals2) Bacteria attracted to root3) Bacteria trigger cell division
4) Infection5) Nodule formation8) Nodule has vascular tissue
Nitrogen CycleNitrogen Cycle
All nitrogen fixing is carried out by Nitrogenase
16ATP 16 ADP
+ 16Pi
8 NADH+H+
NAD+
N2 2NH3 + H2
Where does all the energy come from?
What industrial process achieves this reaction?
Nitrogen CycleNitrogen Cycle
All nitrogen fixing is carried out by Nitrogenase
16ATP 16 ADP
+ 16Pi
8 NADH+H+
NAD+
N2 2NH3 + H2
NH3 is toxic, bacteria and plant quickly convert it to glutamine.
What is glutamine?
Why is this a mutualistic relationship?
glutamine
The Nitrogen CycleThe Nitrogen Cycle
Nitrogen-fixing bacteria in root nodules.
Nitrogen-fixing bacteria Nitrite bacteria
Nitrate bacteria
Nitrogen CycleNitrogen Cycle
Nitrifying Bacteria
NH3 dissolves readily in soil water
NH3 + H+ NH4+
Nitrite bacteria: Nitrosomonas
2NH4 + 3O2 2NO2- + 2H2O + 4H+
Nitrate bacteria: Nitrobacter
2NO2- + O2 2NO3
-
Nitrate ions diffuse freely in soil water and are more readily absorbed by plants.
What type of reaction do these bacteria carry out?
Nitrogen CycleNitrogen Cycle
Nitrifying Bacteria
NH3 dissolves readily in soil water
NH3 + H+ NH4+
Nitrite bacteria: Nitrosomonas
2NH4 + 3O2 2NO2- + 2H2O + 4H+
Nitrate bacteria: Nitrobacter
2NO2- + O2 2NO3
-
Nitrate ions diffuse freely in soil water and are more readily absorbed by plants.
What is the link with eutrophication in lakes and rivers?
The Nitrogen CycleThe Nitrogen Cycle
Nitrogen-fixing bacteria in root nodules.
Nitrogen-fixing bacteria Nitrite bacteria
Nitrate bacteria
Denitrifying bacteria
Nitrogen CycleNitrogen Cycle
Denitrifying Bacteria
Nitrate ions are washed into water table, rivers, lakes and sea.
Water logged soil and mud is anaerobic
Denitrifying bacteria use NO3- as final electron
acceptor in electron transport chain.
NO3- is broken down in N2 gas, released into
atmosphere.
The Nitrogen CycleThe Nitrogen Cycle
Nitrogen-fixing bacteria in root nodules.
Nitrogen-fixing bacteria Nitrite bacteria
Nitrate bacteria
Denitrifying bacteria
Nitrogen CycleNitrogen Cycle
Ammonification
Ammonia released back into the soil by:
Decomposition of protein (decay) by fungi and bacteria
Excretion from animals
Assimilation
Nitrogen in protein passed along food chain
The Nitrogen CycleThe Nitrogen Cycle
Nitrogen-fixing bacteria in root nodules.
Nitrogen-fixing bacteria Nitrite bacteria
Nitrate bacteria
Denitrifying bacteria
Haber process: fertilisers
Lightning
The Nitrogen CycleThe Nitrogen Cycle
1. What is the relevance of nitrogen fixation in crop rotation?
2. Why is good soil drainage important for gardens and arable land?
3. How can high crop yields be explained in water logged paddy fields?
Fertilisers, Farm Waste and Water Fertilisers, Farm Waste and Water PollutionPollution
1) Why do farmers add fertiliser to their fields?
2) What are the advantages and disadvantages of organic and inorganic fertiliser?
One post per idea. Use your real names! Chemical or Organic?http://www.wallwisher.com/wall/kegschgbiology13A
One post per idea. Use your real names! Chemical or Organic?http://www.wallwisher.com/wall/kegschgbiology13b
EutrophicationEutrophication
“is the natural enrichment of water bodies with nutrients over time” (succession)
Accelerated eutrophication is caused by man.
EutrophicationEutrophication
EutrophicationEutrophication
Fertiliser is leached from fields by rain
Water is rapidly enriched with nutrients
Is inorganic or organic fertiliser worse?
EutrophicationEutrophication
Sewage and farm waste be decomposed by bacteria as well as add nutrients to water.
Eutrophication: Data InterpretationEutrophication: Data InterpretationWhat does this chart suggest about eutrophication in the esturies of the USA?What is the percentage of esturaies with high percentage eutrophication?
Which indicator suggests there is a lot of eutrophication in the USA?What does the Dissolved Oxygen indicator suggest?
Are these conlusions valid?
The East Coast has less eutrophication
Are these conlusions valid?
Eutrophication is caused by an increase in human population
Are these conlusions valid?
Eutrophication is increased by warmer temperatures.
Are these conlusions valid?
Eutrophication is caused by farming.
Eutrophication: The Limiting Factor?Eutrophication: The Limiting Factor?
Eutrophication: the limiting factor?Eutrophication: the limiting factor?