AQA Biology 4.7.3.6 · Combined and Triple

Maintaining biodiversity

What people do that harms the variety of life, the five programmes that help, and the pressures that pull the other way.

Combined Science · Foundation tier

Start here

Out come the hedges.

A farmer pulls out the hedges between her fields to grow more wheat.

If you had to guess, would you expect more kinds of birds on the farm afterwards, or fewer?

Human interactions

Harms or helps?

You should be able to describe both positive and negative human interactions in an ecosystem and explain their impact on biodiversity. Decide for each action.

Clearing forest for cattle

Harms or helps?

Replanting a hedgerow on a wheat farm

Harms or helps?

Dumping waste in landfill

Harms or helps?

Recycling paper, glass and metal

Harms or helps?

Burning fossil fuels

Harms or helps?

Fencing off and replanting a rare wetland

Harms or helps?

Five programmes

What is being done.

Scientists and concerned citizens have put in place programmes to reduce the negative effects of humans on ecosystems and biodiversity. Switch the farm, then tap each programme.

One crop from edge to edge supports few species: 9 bird species (made-up count).

A zoo keeps a few dozen of a rare parrot and releases their young into the wild each year. Which programme is this?

Pick one.

Conflicting pressures

What it costs.

Protecting biodiversity competes with other needs: the cost, land for food and housing, and people’s jobs. You should be able to explain and evaluate these conflicting pressures given appropriate information.

Information · made-up data for practice

A farm replanted 4 km of hedgerow and left 3 m field margins. Bird species counted: before, 9; after three years, 17. Wheat harvested: before, 400 tonnes a year; after, 372 tonnes. The scheme cost £18 000; the government paid half.

Which evaluation uses the information fairly?

Pick one.

Think again · just stop polluting?

“Maintaining biodiversity just means stopping pollution.”

Your call

Choose

Which of these is a programme that maintains biodiversity?

Sort

Programme or pressure?

Place each one.

Tap a card, then tap the box it belongs in. Tap a placed card to take it back.

Command words in this lesson

Describe: Positive and negative human interactions and the five programmes.
Explain: How an action changes biodiversity.
Evaluate: A programme against the conflicting pressures, from given information.

Key fact

Five programmes maintain biodiversity: breeding programmes for endangered species; protecting and regenerating rare habitats; field margins and hedgerows on single-crop farms; reducing deforestation and carbon dioxide emissions; recycling rather than landfill. Each conflicts with cost, land or jobs.

Key note · AQA 4.7.3.6

Maintaining biodiversity

Human activities such as pollution, land use, deforestation and global warming reduce biodiversity; positive programmes work against this.
The five programmes: breeding programmes for endangered species; protection and regeneration of rare habitats; reintroduction of field margins and hedgerows on single-crop farms; reducing deforestation and carbon dioxide emissions; recycling resources rather than dumping waste in landfill.
Conflicting pressures: cost, land for food and housing, and people’s livelihoods.
Evaluate from given information: quote the gain, quote the cost, then judge.

Photograph this card. Tomorrow, cover it and say each line first.

Previous and next

Connects to

Ask MrBadmus

Listing programmes without the trade-off?

The farm scheme and its figures are made up for practice.