Land use

Peat bog is a specialised habitat for some living organisms.

Peat has been removed from peat bogs so that the land can be used for farming or forestry.

Give two uses of the peat removed from peat bogs.

The destruction of peat bogs can affect biodiversity.

What is meant by ‘biodiversity’?

Explain how the destruction of peat bogs can affect biodiversity:

• in the local area

• globally.

Peat bogs are estimated to contain twice as much carbon as all the world’s forests.

Figure 13 shows a section through part of a peat bog.

Layer A contains a lot of air.

Layer B:

• contains the dead remains of plants

• has a low pH

• contains very little oxygen

• contains carbon dioxide and methane.

Explain why most of the dead remains of plants in layer B do not decay.

The peat bog in Figure 13 is a stable community.

The moss produces biomass at a rate of 340 g/m²/year.

What is the approximate biomass of the moss that becomes biomass in primary

Tick (✓) one box.

The sundew plant shown in Figure 13 on page 38 has leaves with sticky hairs that trap and digest insects.

Digestion of the insects releases phosphates and simple compounds of nitrogen that are used by the sundew plant.

What substance can the sundew plant make using the phosphates ?

Tick (✓) one box.

What substance can the sundew plant make using the nitrogen ?

Tick (✓) one box.

Humans have destroyed large areas of peat bog to collect peat.

The peat provides fuel and provides compost for gardeners to use.

The peat comes from layer B in Figure 13 on page 38.

Layer B:

• contains the dead remains of plants

• has a low pH

• contains very little oxygen

• contains carbon dioxide and methane.

Figure 14 shows the removal of peat from a peat bog.

Explain how the destruction of peat bogs and the use of peat affects the temperature of the Earth’s atmosphere.

Peat bogs are estimated to contain twice as much carbon as all the world’s forests.

Figure 2 shows a section through part of a peat bog.

Layer A contains a lot of air.

Layer B:

• contains the dead remains of plants

• has a low pH

• contains very little oxygen

• contains carbon dioxide and methane.

Explain why most of the dead remains of plants in layer B do not decay.

The peat bog in Figure 2 is a stable community.

The moss produces biomass at a rate of 340 g/m²/year.

What is the approximate biomass of the moss that becomes biomass in primary

Tick () one box.

The sundew plant shown in Figure 2 on page 4 has leaves with sticky hairs that

trap and digest insects.

Digestion of the insects releases phosphates and simple compounds of nitrogen that are used by the sundew plant.

What substance can the sundew plant make using the phosphates ?

Tick () one box.

What substance can the sundew plant make using the nitrogen ?

Tick () one box.

Humans have destroyed large areas of peat bog to collect peat.

The peat provides fuel and provides compost for gardeners to use.

The peat comes from layer B in Figure 2 on page 4.

Layer B:

• contains the dead remains of plants

• has a low pH

• contains very little oxygen

• contains carbon dioxide and methane.

Figure 3 shows the removal of peat from a peat bog.

Explain how the destruction of peat bogs and the use of peat affects the temperature of the Earth’s atmosphere.

Figure 12 shows the human population from 1600 to 2010.

In 1900 the human population was 1.6 billion.

Calculate how many times greater the human population was in the year 2000 compared with the year 1900.

In 1950 the human population was 2.5 billion.

Calculate the mean annual increase in the human population between 1900 and 1950.

Predict the human population in 2050 if the current rate of population increase continues.

You should draw an extrapolation line on Figure 12.

The increasing human population has caused a decline in fish stocks.

Describe how fishing quotas can help to return fish stocks to a sustainable level.

Farming techniques have changed in recent years.

Describe:

• why more land is being used for farming

• how increased farming has decreased biodiversity.

Genetic modification of crop plants can help meet the demands of the increasing human population.

Golden rice is a genetically modified (GM) crop.

What is the advantage of golden rice compared with non-GM rice?

Tick (✓) one box.

Suggest one reason why some people are concerned about the use of golden rice.

Figure 2 shows the human population from 1600 to 2010.

In 1900 the human population was 1.6 billion.

Calculate how many times greater the human population was in the year 2000 compared with the year 1900.

In 1950 the human population was 2.5 billion. Calculate the mean annual increase in the human population between 1900 and 1950.

Predict the human population in 2050 if the current rate of population increase continues. You should draw an extrapolation line on Figure 2.

The increasing human population has caused a decline in fish stocks. Describe how fishing quotas can help to return fish stocks to a sustainable level.

Farming techniques have changed in recent years. Describe:

• why more land is being used for farming

• how increased farming has decreased biodiversity.

Genetic modification of crop plants can help meet the demands of the increasing human population. Golden rice is a genetically modified (GM) crop. What is the advantage of golden rice compared with non-GM rice? Tick (✓) one box.

Suggest one reason why some people are concerned about the use of golden rice.