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Flashcards in Unit 3: Sustainability Deck (100)
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1

Food security

Is defined as having reliable access to a sufficient quantity of affordable, nutritious food. However:
- 800 million (1 in 9 on Earth) don’t have enough food to lead a healthy active life.
- 1 person in 4 in sub-Saharan Africa is malnourished.
- 1 in 6 children in developing countries is underweight and susceptible to disease. 1 in 4 of the worlds children has stunted growth.
Food security has become a major issue as the worlds population is expected to grow from 7 billion to over 9 billion by 2050.

2

Future food crisis

In the late 18th century, Thomas Malthus, an English clergyman and economist, suggested that population growth would exceed the planets ability to produce food leading to a crisis point where families would keep population growth in check as the carrying capacity of the planet would be reached.
What Malthus didn’t consider was that technological advancements and innovation, particularly machinery, farming chemicals and new agricultural techniques would enable the Earths productivity to be stretched above demand. Theoretically the Earth could currently support a population of 10 billion. However this food, and the ability to produce it, is not evenly distributed.

3

There are a number of concerns over food security, in addition to rising population growth:

- Climate change and processes such as drought, desertification, soil degradation and soil erosion taking agricultural land out of production.
- Changing dietary patterns in developing countries in particular, with an increasing demand for meat (livestock are less efficient in converting energy).
- Increased demand to use agricultural land for energy crops/ biofuels.
- The supply of fertiliser is limited (resources such as potash) and becoming increasingly expensive.

4

Food and Agricultural Organisation (FAO):

In November 2015, the Food and Agricultural Organisation (FAO) of the United Nations set "Zero Hunger" as one of the 17 new Sustainable Development Goals which all countries should work towards by 2030.

5

Changes in farming

Developed countries such as the UK have gone through significant change in agriculture since the Middle Ages.

6

Changes in farming: Agrarain Society

Mainly peasant based, subsistence farmers who only produce enough to feed the,selves and their families. Overlap between consumers and producers.

7

Changes in farming: Industrial Revolution (1800s)

Improved transport networks (rail) allowed food tone transported, some farming and food production processes became mechanised.

8

Changes in farming: Technology Revolution (1940s-)

Widespread technology introduced into farming (machinery, chemicals) significantly increasing yields. Clear separation of producer/ consumer.

9

Post war farming changes

WW2 almost saw Britain and other European nations stave to death. The years which followed saw a push towards maximising food security in key foodstuffs, with considerable investment in agriculture. Changes include:
- Mechanisation of procedures - more efficient, lower labour costs.
- Increased use of agrochemicals - fertilisers (nitrates, phosphates) and pesticides (herbicides, fungicides and insecticides) to boost crop yields.
- Removal of hedgerows and draining of ponds to maximise agricultural land.
- Concentration on growing most profitable crops, especially wheat and barley (leading to monoculture).
- Amalgamation of small farms and growth of agribusiness to improve efficiency.
Generally these changes saw a significant increase in yields, supported government and EU policies where farmers incomes were boosted (through subsidies, grants and loans) to guarantee food security.

10

Diversification

Since the 1980s, some farmers who have struggled financially (especially livestock and dairy farmers) have attempted to boost their incomes by supplementing their incomes with non-farming activities (e.g. bed and breakfast, holiday homes, equestrian centers, camp sites). Grants and loans were available for this e.g. to renovate farm buildings. This can require considerable investment and can take a while to make profits, but it does allow some farmers to operate sustainably in terms of their income.

11

Strategies to increase food production: Chemicals

Advantages:
- Ensures quality and yields of food (fewer pests).
- Doubled yields in. The U.K. since WW2.
- Helps support manufacturing industry, boost economy.
Disadvantages:
- Excess fertilisers lead to algal blooms and eutrophication.
- Pesticides in food chains (bioaccumulation).
- Some insects developing resistance to pesticides due to over-use.

12

Strategies to increase food production: Machinery/ Technology

Advantages:
- Work done more efficiently, saving labour costs.
- Drones (UAVs) and satellite imaging can be used to monitor nutrient levels - saves on fertiliser application.
Disadvantages:
- Larger farmers benefit (can afford investments).
- Heavy machinery compacts soil leading to soil erosion.
- Habitat removal (hedgerows ripped out, ponds drained) to allow machinery space to work.
- Only 1/3 of crops are harvested in ELDCs using machinery.

13

Strategies to increase food production: Irrigation

Advantages:
- Significant increase in yields e.g. Punjab, India.
- Allows cropping during dry seasons - multiple cropping.
Disadvantages:
- Large dams are expensive and can increase water loss via evaporation rates.
- Water being extracted from wells faster than it can be replaced, remaining groundwater supplies are saline.

14

Strategies to increase food production: High Yield Varieties (HYVs)

Advantages:
- "Green Revolution" in ELDCs has significantly boosted yields - reduced famine and malnutrition.
- Sturdy crops not affected by high winds.
Disadvantages:
- HYV crops need a lot of fertilisers, pesticides and water (irrigation) to grow which increases costs and pollution.
- Expensive for peasant farmers (widens rich-poor gulf).

15

Strategies to increase food production: GM Crops

Advantages:
- Plant traits can be transferred into another to produce "super" plant varieties.
- Increased yields - essential to support Earth's growing population?
- Reduce raw materials (e.g. Oil) needed for fertilisers.
Disadvantages:
- Controversial -taking DNA/ genetic structure from one plant or animal and transferring it to another.
- Unknown impact on gene pool.
- Creation of "super weeds" which are resistant to chemicals.

16

Strategies to increase food production: Organic Farming

Advantages:
- Reduces problems from using agrochemicals e.g. toxins in food chains, eutrophication.
- Better quality food produced (less pesticide residue).
- Organic produce can be stored for longer.
- Use of natural biological controls (e.g. ladybirds).
Disadvantages:
- Lower productivity levels.
- Food produced is more expensive (requires more labour inputs and maintenance).
- Only niche market at present (4% of UK food market).

17

Strategies to increase food production: Improved Land Management Techniques

Advantages:
- Essential for peasant farmers in ELDCs (small farms).
- Crop rotation can help restore soil fertility, particularly if legumes are used (restore nitrogen to soil).
- Stone lines are simple methods to reduce soil erosion.
- Terraces reduce soil erosion.
- Intercropping/ agroforestry (talk crops providing shade) helps retain soil moisture.
Disadvantages:
- Difficulties of taking land out of production (fallow periods) with population pressure for food.
- Very labour intensive methods in developing countries, lack of technology and equipment.
- Trees can take time to become established and are vulnerable to drought.

18

Strategies to increase food production: Hydroponics (farming without soil)

Advantages:
- Plants grown in sterile conditions restricts diseases and pests.
- Plants grow 24 hours round the clock e.g. lettuce can mature in 1/3 of the time.
- Crops can be grown in urban locations in confined locations (saving on food miles).
- Uses considerably less water.
Disadvantages:
- Expensive set up costs (installation of LED lighting).
- Higher labour costs.
- Need for qualified/ skilled workers (can be a complex processes).

19

Strategies to increase food production: New Food Sources e.g. Insects

Advantages:
- Currently 2 billion eat insects.
- Abundant.
- Fast growing (mature in 20-30 days) and nutritious (protein rich).
- Can be grown inside in racks limited spaces - reduce demand on land for food (compared to livestock).
Disadvantages:
- Cultural problems in western countries, not accustomed to eating invertebrates.

20

The common agricultural policy (CAP): Advantages

- Significantly increased food production and security in Europe, now self-sufficient in key foods e.g. grain, beef, wine, butter.
- Food price inflation has fallen since the 1970s and prices have become more affordable to consumers.
- Benefitted incomes of farmers who were paid subsidies to grow crops and given guaranteed prices.
- Farming became more industrial which led to a growth in the manufacturing industry e.g. making tractors, farm chemicals.
- EU Farmers against cheap imports from overseas - tariffs imposed on goods from outside Europe.
- Management of the farming landscape is essential for rural tourism (£15bn industry in the UK).

21

The common agricultural policy (CAP): Disadvantages

- Farmers had become "too successful", increased yields led to overproduction in the 1980s (grain "mountains", wine "lakes"). Huge amounts of food were wasted or destroyed.
- Industrial farming had a negative impact on the environment: eutrophication of rivers and streams; bioaccumulation due to pesticides habitat loss (hedgerows and ponds drained).
- Quotas imposed to limit overproduction during the 1980s (milk). However, many dairy forced out of business due to financial losses.
- Set-a-side (1992) - cereal farmers were paid not to grow crops. But very wasteful, abolished in 2009.
- Politicians argue farming gets 40% of total EU budget despite contributing only 2% to overall EU economy. Other industries don't get the same amounts of state/ EU support - huge imbalance.
- CAP payments made to landowners who don't farm but have large grassy areas (e.g. airports, sports clubs).
- Large farmers have benefitted from subsidies at expense of small farmers; subsidies also make it impossible for ELDCs to compete.

22

CAP reform

The traditional system of subsidies paid to farmers has now been updated through single farm payments. Farmers still get payments (subsidies) for land in production, but this is also conditional on practices for "greening" or "environmental stewardship. These include using fewer chemicals, restoring hedges, ponds and woodland, encouraging areas of wild flowers for birds and other organic methods. Crop farmers must also grow at least two types of crop (to reduce monoculture). Incentives for young people to move into farming (average age of British farmer is 59). Farming is typically an unattractive industry for people under 30. More financial support for smaller farmers.

23

Sea fishing: two main types of fish

Pelagic - shallow feeders on nutrients and plankton e.g. herring, mackerel.
Demersal - deep feeders which feeding other species e.g. cod, haddock.

24

Sea fishing: modern fishing methods

Use technology to track and catch large shoals of fish including radar, echo sounding and very large nylon trawl nets. Trawlers are often floating factories with large refrigerated holds so ships can spend long times out at sea maximizing their catch.

25

Sea fishing: problems with modern fishing methods

- Trawling (for demersal species) damages the sea bed, destroying corals and other habitats.
- Industrial methods and overfishing don't give fish stocks time to replenish. Species such as cod and herring in the North Sea and North Atlantic have declined significantly.
- Other species such as seabirds, turtles, sharks and dolphins are uder threat due to being caught in huge nets and unsustainable long line methods.
- Discarded equipment still causes problems for the environment - 1/4 of the rubbish on the bottom of the North Sea is estimated to be fishing equipment.

26

Sea fishing: Common Fisheries Policy (CFP) (EU) - How is the CFP implemented?

- Monitoring numbers of key species (using scientists).
- Quotas. Imposed on species known as the total allowable catch (TAC).
- Pays subsidies to fishermen.
- Restricting days at sea for each boat.
- Catches/ landings must be recorded.
- Restrictions on types and sizes of nets that can be used.
- Minimum size of fish that must be landed.
- Areas (e.g. North Sea) can be closed off to allow fish populations to recover known as "no take zones".
- Promoting alternative species (e.g. oily fish) which are caught sustainably.

27

Sea fishing: Common Fisheries Policy (CFP) (EU) - Criticisms of the CFP

- Large number of discards - small, dead fish which have been thrown back (too small) as they cannot be landed (quotas). Will be gradually phased out between 2015 and 2019.
- Very bureaucratic e.g. rules on net sizes are very complicated.
- Unemployment and decline of fishing ports as trawler men give up way of life.
- Arguably EU fishing fleet is still too large, CFP hasn’t tackled this.
- Conflicts e.g. UK fishing fleet angry that continental boats still allowed to fish in UK waters, despite falling fish stocks.
- CFP encourages price rises in endangered species (creates demand).

28

Aquaculture

Is the farming of aquatic animals and plants in fresh or salt water. It includes growing fin fish (e.g. salmon) in cages/ pens; shellfish grown on the seabed or trestles and growing seaweed. It now accounts for 50% of the worlds fish supply, compared to only 9% in 1980.

29

Aquaculture: Scotland

In Scotland most aquaculture is based on the commercial farming of salmon in large cages in sheltered coastal waters. Stages in reading commercial salmon:

Kelt (mature fish stripped of eggs - spawn)

Eggs (fertilised in hatchery)

Alvein (freshwater tanks, fed artificial diet)

Fry (same as Alvein)

Parr (1-2 years in freshwater)

Smolt (sea cages for 1 or 2 years)

Grilse ( mature fish for harvest)

30

Aquaculture: features of aquaculture in Scotland

- Huge growth industry over last 20 years.
- Scotland now has over 300 salmon farms around the west coast, Western Isles, Orkney and Shetland, in sheltered sea licks and inlets.
- Scotland produces 80% of farmed fish in the UK.
- Supports over 6000 jobs including 1500 in actual fish farms.
- Planned expansion to increase productivity, notably by Marine Harvest.