5.2 Agriculture and foodIB Environmental Systems and Societies HL: Subtopic test

1. 1
   A middle-income country produces more than enough food energy for every citizen. Yet national health data show that 11% of children under five are stunted (too short for their age), while 28% of adults are obese. Fruit and vegetables often travel long distances and about a third are wasted before reaching shops, while cheap, highly processed food is widely available.

   (a)

   Which statement about malnutrition is correct?

   [1 mark]

   • AIt means only a lack of calories
   • BIt only affects low-income countries
   • CIt only means being overweight
   • DIt includes both diseases of undernourishment and diseases of overnourishment

   (b)

   Which statement best explains why stunting and obesity exist together in the same country?

   [1 mark]

   • AThe country does not produce enough food
   • BFood distribution patterns and variations in food quality reflect how the food supply industry functions
   • CObesity is caused only by individual choice
   • DStunting is caused only by climate

   (c)

   Distinguish between diseases of undernourishment and diseases of overnourishment, giving one example of each.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A large commercial maize farm in the US Midwest applies synthetic nitrogen fertiliser every year to keep yields high. A neighbouring farm grows maize in rotation with clover and soya beans, spreads compost, and keeps the soil covered with plants during winter.

   (a)

   Why do many intensive farming systems use synthetic fertilisers?

   [1 mark]

   • ATo maintain high commercial productivity, though at the expense of sustainability
   • BTo increase biodiversity in the soil
   • CTo reduce the need to irrigate
   • DTo increase the soil's carbon store

   (b)

   Which is a sustainable method of improving soil fertility?

   [1 mark]

   • ABurning crop residues on bare soil
   • BRepeatedly growing maize on the same field
   • CRotating crops, including nitrogen-fixing legumes such as clover
   • DIncreasing synthetic pesticide use

   (c)

   Outline two soil conservation techniques used on the neighbouring farm and a benefit of each.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A company runs a vertical farm in a city warehouse, growing lettuce in stacked trays under artificial light. It reports the following per year. Vertical farm: 60 kg of lettuce per m² of floor area; 15 kWh of electricity per kg; 5 litres of water per kg. Conventional field production: 6 kg per m² of land; 0.5 kWh of electricity per kg (machinery and transport); 250 litres of water per kg.

   (a)

   Calculate how many times greater the yield per m² is on the vertical farm, and the percentage reduction in water use per kg compared with the field.

   [3 marks]

   (b)

   Evaluate the sustainability of vertical farming compared with field production, using the data.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   Polyface Farm in Virginia, USA, moves its cattle to a fresh paddock every day (mob grazing). Chickens in mobile coops follow the cattle, scatter the dung and eat fly larvae, and pigs are used to turn compost. The farm uses no synthetic fertiliser and sells its produce to nearby customers. Critics argue that such systems produce less food per hectare than industrial farming and could not feed a world population of eight billion.

   (a)

   Explain how regenerative farming techniques such as those used on this farm can improve soil and productivity.

   [6 marks]

   (b)

   Evaluate the claim that low-productivity, alternative food systems such as this are sustainable, given the need to feed the wider global population.

   [6 marks]

   Total for question 4: 12 marks

End of questions