Topic 5: Soil systems and terrestrial food production systems and societies Flashcards
To what extent is pollution impacting human food production systems?
Terrestrial
aquatic
water pollution
soil pollution
GWEICO
JUST REMIND YOURSELF ON HOW
understanding concepts and terminology of aquatic and terrestrial food production; aquaculture, capture fisheries, aquatic sp. harvesting; provision of food to a growing population; aquatic pollution sources; wide range of parameters lowering water quality; soil content; soil degradation; soil fertility; sustainability of TPSs influenced by industrialization, fossil fuel use, mechanization, fertilizers, pesticides; acid deposition; tropospheric ozone; ozone depletion; eutrophication; dead zones; climate change (Note: Relevant examples will be of pollution affecting food production NOT the other way round);
breadth in addressing and linking a range of pollutants/polluting activities (fertilizer use/emissions from combustion of fossil fuels/mining/waste disposal etc) and their impacts on food production systems (aquaculture/terrestrial farming systems) and methods of limiting these impacts (alternative sources /regulations/clean-up procedures);
examples of food production systems; farming practices (aquatic and terrestrial); impacts of pollutants/polluting activities; and methods of limiting impacts;
balanced analysis of the extent to which a range of pollution events are impacting, or being restored/prevented from impacting, a range of different food production systems;
a conclusion that is consistent with, and supported by, analysis and examples given eg ‘Terrestrial FPSs are affected by a wider range of pollutants and polluting activities, thus aquatic FPSs show a greater potential for sustainable production feeding the fast-growing global population’.
State one transfer of matter occurring within the soil profile.
leaching
TRANSLOCATION
biological mixing by soil animals/earthworms / / seepage / capillary action / drainage / percolation / infiltration / eluviation / absorption of minerals/water by living organisms.
Do not accept INPUTS of matter eg precipitation, leaf litter, parent material, particle deposition or OUTPUTS of matter eg erosion; or TRANSFORMATIONS of matter eg evaporation/weathering.
Identify one example of an output to the atmosphere from the soil system.
Nitrogen (from denitrification)
/ soil particles/erosion (from wind)
/ CO2 (from soil organism respiration) /
/ water (vapour from evaporation)
/ heat (from radiation/conduction)
methane (from anaerobic decomposition).
Do not credit the processes in brackets … these may give rise to the outputs but are not themselves an output from the soil.
Describe two characteristics of soil with high primary productivity.
CHARACTERISTICS OF LOAM SOIL
high availability of minerals/inorganic nutrients;
medium particle size
optimum/ / loam soils / mixed/balanced composition of sand/silt/clay;
allow good drainage/permeability/resist water-logging;
prevent excessive leaching/good water-holding capacity;
provide sufficient air space/porosity for root growth/O2 supply;
contain ample dead organic matter/humus (for decomposers);
healthy/abundant decomposing community/soil organisms;
appropriate pH (6.0–6.8).
State one transformation process occurring within the soil profile
decomposition;
humus formation/humification of organic matter;
weathering of primary minerals/parent rock;
nutrient cycling/nitrogen fixation/nitrification/denitrification/ammonification;
evaporation;
rusting soil.
Outline two conservation methods that could be used to reduce soil erosion.
COVER CROPPING
CONTOUR PLOUGHING
TERRACING
Cultivation techniques:
contour ploughing with furrows following the contour lines/at right angles to the slope/to reduce runoff;
terrace farming forms a series of steps in the hillside area/to prevent run-off;
maintaining cover crops/plant roots/stubble/mixed agriculture/agroforestry to hold soil in place between harvesting;
mulching consists of applying organic material over the exposed soil / preventing surface runoff;
buffer strips/vegetative areas by watercourses to reduce run-off/water erosion;
adding soil conditioners/lime/humus/organic material/fertilizers to increase root growth/hold soil together;
wind reduction techniques, eg wind/shelter breaks to prevent wind erosion;
avoid overgrazing/over-cropping/monoculture which degrades soil texture;
zero/minimum tillage reduces soil agitation/potential for erosion;
trickle/drip irrigation reduces run-off causing erosion.
Climate can both influence, and be influenced by, terrestrial food production systems.
To what extent can terrestrial food production strategies contribute to a sustainable equilibrium in this relationship?
understanding concepts and terminology of equilibria, sustainability, natural capital/income, climatic factors (temp/precipitation/seasonality), greenhouse gases, climate change, biome shifts, water conservation, irrigation, desertification, vegetarian vs meat-rich diets, mitigation, adaptation, commercial vs artisanal, intensive vs extensive, food miles, selective breeding/genetic engineering, etc;
breadth in addressing and linking influences of climate on food production eg water scarcity, shifting biomes, mean temperatures / precipitation, desertification, wind / rain / erosion, etc and influences of food production on climate eg methane production, deforestation, use of fossil fuels, global transport, etc and ways in which production strategies may adapt to, or mitigate climate change;
examples of food production strategies that adapt to climate change eg water conservation, drip irrigation, terracing, drought/temperature resistant crops, aquaponics, greenhouses, etc and strategies that mitigate climate change eg switching from meat-rich diets, localising food production, employing artisanal/low-energy farming strategies, etc;
balanced analysis of the extent to which production strategies from a range of contexts may contribute to, or mitigate against, an equilibrium between food production and the climate etc;
a conclusion that is consistent with, and supported by, analysis and examples given eg “although there are many production strategies that mitigate or adapt to climate change, the relationship has already shifted so far away from a sustainable equilibrium, and with growing populations, it seems unlikely that their contribution will be sufficient to avoid a tipping point in the future”;
Outline two ways in which the soil quality in the pioneer stages of the succession model shown in Figure 1 will differ from that in the climax ecosystem.
In pioneer communities…
there will be lower organic content/leaf litter (due to combustion from the fire);\
there may be fewer soil organisms (following deaths from fire);
there may be a higher concentration of available minerals (released from ashes);
it will be more prone to erosion/evaporation losses (through lack of vegetation cover/roots by fire);
less established nutrient recycling / reduced decomposer community;
Compare and contrast the impact of two named food production systems on climate change.
named food production system with description; (eg Iowa corn production in mid-west USA is highly intensive, relying upon large machinery and inorganic nitrogen fertilizers)
named food production system with description; (eg rice-fish farming in China is a low-intensity system managed by human labour, with few chemical inputs)
use of machinery vs human labour, dependency on fossil fuels;
use of organic vs inorganic fertilizers, intensive energy needs of production of inorganic fertilizers/NOx released from use of inorganic fertilizers;
animal vs plant production, animals require more land use due to position in food chain;
types of greenhouse gases produced, eg both rice and animal production produce methane;
eg case study: Rice-fish farming in Thailand [1] vs cattle farming in US [1]. Both rice and cattle produce methane, a greenhouse gas [1]. Inorganic fertilisers used in cattle farming releasing nitrogen oxides into atmosphere [1]. Rice is fertilised naturally from fish faeces so has no direct impact on climate change [1]. Cattle farming involves use of heavy machinery / fossil fuels not used in rice fish farming [1]. Rice farming produces food at lower trophic level so absorbs carbon dioxide [1].
Notes: Award [2] max for description of food production systems.
Other points of comparison or contrast may be acceptable but must be explicitly linked to climate change in order to gain credit.
Award [4] max if only points of comparison or only points of contrast are addressed
Credit can be given for any points of comparison or contrast with regard to impact on climate change/release of greenhouse gases.
Discuss how human activities impact the flows and stores in the nitrogen cycle.
understanding concepts and terminology of systems approach; flows and (biotic and/or abiotic) stores in nitrogen cycle; atmospheric content; farming practices (aquatic and terrestrial); soil; eutrophication; urbanization, deforestation; transportation; forest fires; use of fossil fuels;
breadth in addressing and linking climate change; photochemical smog; secondary pollutant; acid deposition; scrubbers/catalytic converters; renewable vs. non-renewable energy sources; population growth; EVSs; sustainable development;
examples of farming practices (aquatic and terrestrial) which affect nitrogen flows; eutrophication/pollution management strategies; specific human activities causing atmospheric pollution;
balanced analysis discussing activities which increase nitrogen flows and stores, as well as decreasing or managing these flows and stores;
a conclusion that is consistent with, and supported by, analysis and examples given eg probably the greatest human disturbance to steady state equilibrium in the nitrogen cycle is the increase of inorganic stores such as nitrogen oxides in the atmosphere and nitrates in aquatic systems.
With reference to four different properties of a soil, outline how each can contribute to high primary productivity.
PARTICLE SIZE
PERMIABILITY
POROSITY
MICROORGANISMS AVAILABLE
particle size affects ability of soil to store/retain water necessary for productivity;
high mineral content provides nutrients for healthy growth/productivity;
high organic content / deep humus provides long term storage of nutrients (released through decomposition);
air spaces provide more O2 to roots for growth/respiration / allow deeper penetration of roots;
appropriate porosity allows soil to hold enough water for plant growth;
better drainage prevents water-logging that inhibits growth/productivity;
abundant biota help to aerate/break up the soil allowing for better root growth/recycle nutrients;
microorganisms contribute to mineral-cycling promoting growth/productivity;
neutral to slightly acidic pH is the optimal for most plants (6.0–7.5);
low or no slope prevents water erosion / loss of soil;
To what extent is London a sustainable city?
Sustainable [4 max]:
recycling of SDW will reduce CO2 from decomposition, reducing EF;
recycling of SDW will reduce space required for landfill, reducing EF;
vertical farming increases biocapacity / repurposing brownfield sites/empty industrial buildings means land does not need to be cleared for agriculture (increasing sustainability)/increases productive land area;
urban agriculture reduces importation of food which reduces carbon dioxide emissions from transportation;
no pesticides means a reduction in toxification of soil/water, increasing sustainability;
bee-keeping helps protect/raise healthy bees which are needed for biodiversity of plants;
reduction in water use for vertical farming increases sustainability;
air pollution control measures will reduce negative impact on human health and vegetation;
large amount of green space/habitat for biodiversity;
aiming to produce 15 % of energy from renewable, local sources, which increases sustainability/reduces EF;
deer are managed to ensure environment remains healthy;
money raised from selling deer meat goes to conservation increasing sustainability/protection of habitat;
there are over 8 million trees/47 % is classified as green space, providing oxygen /acting as a carbon sink/trees clean air of pollutants, which increases sustainability;
Not sustainable [4 max]:
EF is larger than biocapacity, which means it is not sustainable;
recycling requires energy and produces air pollution, which increases EF;
low recycling rates (compared to rest of UK)/lower than 35 %, so not sustainable / only paper and glass have more than 50 % recycled;
growth in population will increase demand for land (housing) and energy, so improvements may be counteracted by increased population;
green spaces are fragmented / green spaces are divided by urban barriers, so wildlife cannot move freely between habitats;
central London suffers from high levels of air pollution, which is not sustainable;
deer numbers rise rapidly and then crash, suggesting numbers are exceeding carrying capacity, which is not sustainable/habitat is being damaged;
only aiming for 15 % energy from renewables, which isn’t using resources wisely;
Conclusion [1 max]: While many aspects of the urban management of London contribute to its sustainability such as use of vertical farming that helps to conserve water, the vast population in a relatively small area means that its environmental footprint far exceeds the area of the city.
Outline how climate change may affect the availability of freshwater resources.
[2]b.
ncreased temperatures/evaporation may lead to increased loss of soil water/aridity/desertification;
increased temperatures/evaporation may cause loss/salination of water supplies lakes etc;
changes in precipitation/increased frequency of El Nino events may lead to increase/decrease of water supply/droughts;
rising sea levels may lead to inundation/salination of ground water;
increased temperatures may cause melting of glaciers/ice caps leading to increase/decrease of water availability (i.e. by increased input to lakes/run-off to oceans).
Outline two reasons why loam soils are the most productive for plant growth.
because it is a good balance of sand and clay avoiding each of their more negative qualities;
not prone to waterlogging / has good drainage (compared to clay);
allows easy root penetration / workability (compared to clay);
allows good aeration / oxygen supply to roots (compared to clay);
stable / not prone to wind erosion (compared to sand);
retains moisture (compared to sand);
retains nutrients/minerals (compared to sand).
