Agriculture And Biodiversity

Question 1

Farmers are now being encouraged to replant hedges on their land.

Suggest and explain one advantage and one disadvantage to al
farmer of replanting hedges on her farmland.
2 marks

Answer 1

Advantage - 1 mark
Greater (bio)diversity so increase in predators of pests
Or
Increase in predators of pests so more yield/income/less pesticides/less damage to crops
OR
Increase in pollinators so more yield/income
OR
May attract more tourists/subsidies to their farm so more income (from diversification);

Disadvantage - 1 mark
Reduced land area for crop growth/income
OR
Greater (bio)diversity so increase pest population
OR
Increase pest population so less yield/less income/(more) need for pesticides/(more) damage to crops
OR
Increased (interspecific) competition so less yield/income
OR
More difficult to farm so less income;

Accept description of yield eg crop growth.
For ‘crop’ accept ‘plant’.
Accept other valid suggestions with explanation that will affect the farm as a whole.
Examples of ‘more difficult to farm’ - can’t use large machinery, more difficult to plough/seed/harvest.

Question 2

The index of diversity of the insects was higher in the hedge than in the barley field

Suggest why

3 marks

Answer 2

1. More plant species;
2. More food sources / variety of food;
3. More habitats / niches;
   Allow converse for barley field
   More food = neutral

Question 3

The UK government pays farmers to leave grassy strips around the edges of fields of crops. These grassy strips contain a variety of plant species. Leaving the strips is an attempt to encourage biodiversity of animals.

(a)
Give two reasons why the grassy strips increase the biodiversity of animals.

2 marks

Answer 3

1. Increase in plant diversity leads to more types of food for animals
2. Increase in variety of animals leads to increase in predator species
3. Increase in niche / habitats