B6.2 - Food Security Flashcards
describe 5 factors affecting levels of food security
- increasing human population
- changing diets in wealthier population
- new pests and pathogens
- climate change
- sustainability and cost of agricultural inputs
why does an increasing human population affect food security?
more people = more food needed
how does changing diets in wealthier countries affect food security?
- each person wants good food (ie. imported), or more meat (less security)
how does climate change affect food security?
- global warming causes more droughts
- higher desertification
- unpredictable rain
positives of higher CO2 levels in the air?
- they may increase crop yields (for photosynthesis)
how does increasing agriculture costs affect food security?
- more expensive to grow food/store/distribute
- so price is too high for other people to afford
define food security
the ability of human populations to access food of sufficient quality and quantity
state 5 agricultural solutions to the demands of the growing human population
- hydroponics
- biological control
- gene technology
- fertilisers
- pesticides
describe hydroponics
- growing crops by replacing soil with mineral solution
- can control growth by changing temperature
positives of hydroponics
- mineral solution can be recycled
- plants grow quickly
- more plants can grow n the same space (can be stacked on top of each other)
negatives of hydroponics
- very expensive (set-up costs, constant power required, maintenance costs)
- susceptible to waterborne diseases
describe biological control
- release a natural predator
- to kill pests where a crop is being grown
disadvantages of biological control?
- may affect other organisms in the food web
- predator may be hard to control
advantages of biological control
is an alternative to pesticide, so an organic farming method
how would gene technology solve the demands of a growing human population?
produce them to have better yields (disease resistant, pest resistant)
how do herbicides and pesticides solve the demand of a growing human population?
- remove animals that eat crops
- herbicides get rid of competing crops
negatives of pesticides and herbicides?
- reduces biodiversity
terrible answer tbh -> you should know what you should write
- pesticides may pass up the food chain
difference between intensive farming and organic farming?
organic = avoid use of chemicals, smaller yields
intensive = main goal is maximum yield (ie. caged animals = maximum energy for mass and not movement)
define sustainable food production
producing food that can be continued for an indefinite period of time
negatives of fish farming? (3)
- disease spread quickly
- expensive
- water quality may be bad as faeces pollutes water
what is selective breeding?
when humans breed certain plants or animals which have desirable characteristics (ie. may use it to increase crop yield)
3 step process in which selective breeding occurs?
1) select individuals with desirable characteristics + breed together
2) breed best offspring
3) repeat over many generations
disadvantages of selective breeding?
- reduces gene pool (vulnerable to new pathogens)
- increased chances of inherited diseases
- unforeseen physical problems (too heavy to walk)
how has selective breeding affected food plants?
- wheat has large ears
- generally in a way to increase crop yield
- wheat ripens at the same time
