Download Revision AS ES

Revision AS ES
Paper 2
Discuss the factors which influence
soil fertility.
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Texture;
influences/leaching/eluviation;
sands well drained/few nutrients;
clays may be waterlogged/hold nutrients
waterlogging reduces O2;
• structure;
• peds .
• ploughing can break up pans/improve
aeration/reduce compaction;
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nutrient content;
humus/organic matter/faeces;
biota/soil organisms;
biotic activity;
• shallow soils may not offer sufficient
nutrients/support;
• aeration needed to provide O2;
• for respiration/active uptake/nutrient
uptake;
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pH determines nutrient availability;
moisture needed for nutrient uptake;
18 NPK/macro/micronutrients;
Nitrogen fixation- legumes;
nutrient input from precipitation;
nutrient input from (weathered) parent
material;
Nitrogen cycle
Processes
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Nitrification
Leaching/ infiltration
Nitrogen fixation
Denitrification
Decomposition
Absorption
There is a constant movement of carbon
between the oceans and the atmosphere.
• Suggest three factors that influence the
speed of this movement.
Factors that influence the speed of
this movement
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Temperature/heat;
turbulence/upwelling;
concentration gradient;
pressure;
photosynthesis;
decomposition/decay;
respiration;
• Explain how land use change can increase
the amount of carbon dioxide in the
atmosphere.
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Changed photosynthesis
afforestation
deforestation
draining/ploughing of soils
increased aerobic decomposition
Urbanisation
release from fossil fuel
• Suggest how a carbon atom, breathed out
in a carbon dioxide molecule by a
dinosaur, ended up in a lump of coal.
carbon dioxide molecule
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Absorbed by plant during photosynthesis;
Assimilated into dinosaur’s tissues;
Death decomposition of dinosaur
Burial
Compaction/pressure/lithification;
Gas
Nitrogen
Carbon dioxide
Ozone
Methane
Normal %
of gas in
dry air
One source of gas
Type of
electromagnetic
radiation
absorbed by the
gas
N/A
Gas
Normal %
of gas in
dry air
One source of gas
Type of
electromagnetic
radiation
absorbed by the
gas
Nitrogen
78
denitrification
N/A
Carbon dioxide
0.035
Respiration
Infra red
Ozone
0.000007
Combination of
O2 and O in the
stratosphere
Ultraviolet
Methane
trace
anaerobic
decomposition
Infra red
Water quality/ use
• The degree to which water is treated and
purified depends upon its final use.
• Describe the processes of water treatment
and how the final use of the water affects
which processes are used.
Processing
• Screens
– filter/bars/grills;
– remove large/floating/gross solids;
• Settling/sedimentation;
– static water;
– removes suspended solids;
• Flocculation/coagulation;
– alum/polyelectrolytes/neutralises electrical charges;
– removes clay/colloidal material;
• aeration
– reaction with oxygen;
– remove odours/some metals/organic matter;
• (activated) carbon;
– adsorption;
– removes some organic compounds/pesticides;
• disinfection/sterilisation;
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chlorine/UV/ozone;
kills bacteria/pathogens;
fluoridation;
less susceptible to acid attack;
aids dental health;
• water softening;
– ion exchange/distillation;
– remove lime/calcium ions;
• demineralisation;
– distillation/ion exchange;
– remove named dissolved ions/chemicals;
• pH control;
– add lime;
– neutralise acids;
Uses of water and quality
requirement
• drinking water/food processing
– bacteria/odours/taste/toxins/pH/colour
• irrigation water
– salt content/pathogens/acids
• steam turbine water
– dissolved minerals corrosiveness
• reactor primary coolant water
– mineral content/corrosiveness/reactivity
• condenser water
– gross solids
• textile industry
– hardness/turbidity