Flashcards in Food Security Deck (24)
What is national food security?
Having sufficient food to adequately feed all the individuals in a country.
How is South Africa at a national level secure?
-produces its main staple foods
- exports surplus food and wine.
- import what it needs to meet food requirements
What does household access to food depend on?
- regular supply of food
- being able to pay for food
What affects food security?
- Human population growth
- droughts and floods
- Poor farming practices
- Pest control
- Loss of topsoil
How does Human pop affect food security?
Domestic consumption of food will be more than its production.
How does droughts and floods affect food security?
Cause crop failure which reduces the amount of available food
What happens in many wet areas?
They receive more rain, more frequently, lead to more floods that damage crops.
What happens in dry areas?r
Receive even less rain, longer droughts, which lead to desertification of drylands
What is monoculture?
Planting one crop species in the same area for extended periods
What are the disadvantages of monoculture?
- Soil erosion
- Leaching of macro- and micro-nutrients
- pollution of rivers
- no genetic variety in plants,prone too:
- infections of pest
Why are pesticides used for pest control?
protect crops and help to ensure food security
What are pesticides?
toxic chemicals used to control crop damage by insects, bacteria...
What happens when pesticides are over- used?
- Accumulate in food chains
- kill natural predators
- cause pesticide resistant species
- interfere with breeding of mammals and birds.
Why does soil erosion occur, when top soil is washed away.?
- Change in the structure of the soil
- lack of vegetation to bind soil
What is soil erosion?
The removal of soil by water or by wind
What are fertilisers?
Any organic or inorganic material of natural or synthetic origin that is added to the soil to supply one or more plant nutrients essential to the growth of plants.
Why are fertilisers important?
Ensure high crops to yield.
Why are fertilisers becoming a problem?
- apply more than they should, impacts nutrients on soil and crops
- use cheapest fertiliser
How can the problem with the use of fertilisers be solved?
applied in a more balanced way.
What is genetic engineering?
Isolating genes that control a specific trait of an organism and insert genes into other organisms which will then have the required trait?
Why are crops genetically engineered?
generate more useful and productive crop varieties containing new combinations of genes
What are the advantages of genetic engineering?
- Give increased yields to help sustain food security
- create plants to withstand long droughts, more crops can be grown in different areas.
What are the disadvantages of genetic engineering?
- Genetic diversity reduced due to growth in monocultures
- possible health risks
- interbreeding can occur.