The variety of all the different species of organisms on Earth, or within an ecosystem.

How does a high biodiversity help to keep an ecosystem stable?

It reduces the dependence of one species on another for food , shelter and maintenance of the physical environment , so the loss of one species is less likely to cause others to disappear.

Give three human activities (or their consequences) that are reducing biodiversity .

Producing waste (pollution and habitat loss) Deforestation (loss of high-biodiversity habitats) Global warming (disruption of habitats and ecosystems)

Why does the future of the human species rely on maintaining good biodiversity ?

We rely on photosynthetic organisms for oxygen We rely on pollinators (e.g. bees) for food crops We rely on many plant species for medicines

The future of the human species on Earth relies on us maintaining a good level of .

The future of the human species on Earth relies on us maintaining a good level of biodiversity .

True or False? A high biodiversity increases how much one species depends on another for survival.

False. A high biodiversity reduces the dependence of one species on another, which makes the ecosystem more stable .

Why has the human population grown so rapidly ( exponentially ) over the last 150 years?

Improved technology and food supply → higher birth rate Improved medicine, hygiene and healthcare → lower death rate

As the human population and standard of living rise, more resources are used and more is produced.

As the human population and standard of living rise, more resources are used and more waste is produced.

Give the three places pollution can occur, with an example source of each.

Water → sewage, fertiliser or toxic chemicals Air → smoke and acidic gases Land → landfill and toxic chemicals

Name three sources of water pollution .

Sewage , fertiliser and toxic chemicals .

How does pollution affect biodiversity?

Pollution kills plants and animals , which reduces biodiversity .

Pollution kills plants and animals, which biodiversity.

Pollution kills plants and animals, which reduces biodiversity.

Give four ways humans reduce the amount of land available for other plants and animals.

Building , quarrying , farming and dumping waste .

Partly decomposed plant material that builds up in waterlogged, acidic bogs , where a lack of oxygen stops the plants decaying fully. It stores large amounts of carbon .

Why are peat bogs destroyed by humans?

Drained to provide land for farming Dried and burned as a fuel Used to produce compost for gardens and farms

How does destroying peat bogs reduce biodiversity ?

Peat bogs are habitats for many species (e.g. migrating birds). Destroying them removes this habitat, so the variety of species that can live there falls.

The decay or burning of peat releases dioxide into the atmosphere.

The decay or burning of peat releases carbon dioxide into the atmosphere.

True or False? Destroying peat bogs mainly releases methane into the atmosphere.

False. Destroying or burning peat mainly releases carbon dioxide into the atmosphere.

The clearing of trees , usually on a large scale. It is unsustainable when forests are cut down faster than they can regrow.

Why has large-scale deforestation occurred in tropical areas?

To provide land for farming (e.g. cattle and rice fields) To grow crops for biofuels

Give three undesirable effects of deforestation.

Extinction of species (loss of biodiversity) Loss of soil and increased flooding Increased carbon dioxide in the atmosphere

Explain how deforestation increases the amount of carbon dioxide in the atmosphere.

Fewer trees means less photosynthesis , so less CO 2 is removed from the air Burning the trees releases stored carbon as carbon dioxide

Deforestation reduces biodiversity because it destroys the of many species.

Deforestation reduces biodiversity because it destroys the habitats of many species.

Give a source of the extra carbon dioxide and methane entering the atmosphere.

Carbon dioxide → combustion of fossil fuels Methane → cattle digesting food, and rice paddy fields

A gas that absorbs heat (infrared radiation) and traps it in the Earth's atmosphere. Rising levels increase the greenhouse effect, causing the Earth's average temperature to rise.

Describe some biological consequences of global warming.

Loss of habitats (e.g. from rising sea levels and flooding) Reduced biodiversity as food chains are disrupted and extinction increases Changes in distribution/migration of species, including the spread of pests and disease

Why is there strong confidence in the science of global warming?

There is a scientific consensus based on systematic reviews of thousands of peer-reviewed publications (scientists checking each other's work).

Increasing levels of carbon dioxide and in the atmosphere contribute to global warming.

Increasing levels of carbon dioxide and methane in the atmosphere contribute to global warming.

Give some negative human interactions that reduce biodiversity in ecosystems.

Waste production , destruction of peat bogs , deforestation and contributing to global warming .

Describe positive actions humans take to maintain biodiversity.

Breeding programmes for endangered species Protection and regeneration of rare habitats Reintroducing field margins and hedgerows on farmland Reducing deforestation and carbon dioxide emissions Recycling resources rather than dumping waste in landfill

Strips of land around the edges of fields left to grow wild, which increase biodiversity by providing habitats for insects, wildflowers and other species.

Explain one conflicting pressure that makes maintaining biodiversity difficult.

Protecting biodiversity can be expensive or reduce food production — e.g. land used for field margins could instead grow crops, so farmers may need a subsidy to make up for lost income.

programmes are used to increase the numbers of endangered species and help maintain biodiversity.

Breeding programmes are used to increase the numbers of endangered species and help maintain biodiversity.

Why might governments pay farmers a subsidy to keep field margins and hedgerows?

The land used for margins and hedgerows could otherwise grow sellable crops , so a subsidy makes up for the farmer's lost income while protecting biodiversity.

GCSEScienceAQACombined Science: TrilogyBiologyFlashcardsEcologyBiodiversity & the Effect of Human Interaction on Ecosystems

Biodiversity & the Effect of Human Interaction on Ecosystems (AQA GCSE Combined Science: Trilogy: Biology): Flashcards

Exam code: 8464

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FrontBiodiversity
Biodiversity
FrontBiodiversity
Give three human activities (or their consequences) that are reducing biodiversity.
BackBiodiversity
Producing waste (pollution and habitat loss)
Deforestation (loss of high-biodiversity habitats)
Global warming (disruption of habitats and ecosystems)

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Cards in this collection (35)

Biodiversity
The variety of all the different species of organisms on Earth, or within an ecosystem.
How does a high biodiversity help to keep an ecosystem stable?
It reduces the dependence of one species on another for food, shelter and maintenance of the physical environment, so the loss of one species is less likely to cause others to disappear.
Give three human activities (or their consequences) that are reducing biodiversity.
- Producing waste (pollution and habitat loss)
- Deforestation (loss of high-biodiversity habitats)
- Global warming (disruption of habitats and ecosystems)
Why does the future of the human species rely on maintaining good biodiversity?
- We rely on photosynthetic organisms for oxygen
- We rely on pollinators (e.g. bees) for food crops
- We rely on many plant species for medicines
The future of the human species on Earth relies on us maintaining a good level of .
The future of the human species on Earth relies on us maintaining a good level of biodiversity.
True or False?
A high biodiversity increases how much one species depends on another for survival.
False.
A high biodiversity reduces the dependence of one species on another, which makes the ecosystem more stable.
Why has the human population grown so rapidly (exponentially) over the last 150 years?
- Improved technology and food supply → higher birth rate
- Improved medicine, hygiene and healthcare → lower death rate
As the human population and standard of living rise, more resources are used and more is produced.
As the human population and standard of living rise, more resources are used and more waste is produced.
Give the three places pollution can occur, with an example source of each.
- Water → sewage, fertiliser or toxic chemicals
- Air → smoke and acidic gases
- Land → landfill and toxic chemicals
Name three sources of water pollution.
Sewage, fertiliser and toxic chemicals.
How does pollution affect biodiversity?
Pollution kills plants and animals, which reduces biodiversity.
Pollution kills plants and animals, which biodiversity.
Pollution kills plants and animals, which reduces biodiversity.
Give four ways humans reduce the amount of land available for other plants and animals.
Building, quarrying, farming and dumping waste.
Peat
Partly decomposed plant material that builds up in waterlogged, acidic bogs, where a lack of oxygen stops the plants decaying fully. It stores large amounts of carbon.
Why are peat bogs destroyed by humans?
- Drained to provide land for farming
- Dried and burned as a fuel
- Used to produce compost for gardens and farms
How does destroying peat bogs reduce biodiversity?
Peat bogs are habitats for many species (e.g. migrating birds). Destroying them removes this habitat, so the variety of species that can live there falls.
The decay or burning of peat releases dioxide into the atmosphere.
The decay or burning of peat releases carbon dioxide into the atmosphere.
True or False?
Destroying peat bogs mainly releases methane into the atmosphere.
False.
Destroying or burning peat mainly releases carbon dioxide into the atmosphere.
Deforestation
The clearing of trees, usually on a large scale. It is unsustainable when forests are cut down faster than they can regrow.
Why has large-scale deforestation occurred in tropical areas?
- To provide land for farming (e.g. cattle and rice fields)
- To grow crops for biofuels
Give three undesirable effects of deforestation.
- Extinction of species (loss of biodiversity)
- Loss of soil and increased flooding
- Increased carbon dioxide in the atmosphere
Explain how deforestation increases the amount of carbon dioxide in the atmosphere.
- Fewer trees means less photosynthesis, so less CO₂ is removed from the air
- Burning the trees releases stored carbon as carbon dioxide
Deforestation reduces biodiversity because it destroys the of many species.
Deforestation reduces biodiversity because it destroys the habitats of many species.
Which two greenhouse gases, increasing due to human activity, contribute to global warming?
Carbon dioxide and methane.
Give a source of the extra carbon dioxide and methane entering the atmosphere.
Carbon dioxide → combustion of fossil fuels
Methane → cattle digesting food, and rice paddy fields
Greenhouse gas
A gas that absorbs heat (infrared radiation) and traps it in the Earth's atmosphere. Rising levels increase the greenhouse effect, causing the Earth's average temperature to rise.
Describe some biological consequences of global warming.
- Loss of habitats (e.g. from rising sea levels and flooding)
- Reduced biodiversity as food chains are disrupted and extinction increases
- Changes in distribution/migration of species, including the spread of pests and disease
Why is there strong confidence in the science of global warming?
There is a scientific consensus based on systematic reviews of thousands of peer-reviewed publications (scientists checking each other's work).
Increasing levels of carbon dioxide and in the atmosphere contribute to global warming.
Increasing levels of carbon dioxide and methane in the atmosphere contribute to global warming.
Give some negative human interactions that reduce biodiversity in ecosystems.
Waste production, destruction of peat bogs, deforestation and contributing to global warming.
Describe positive actions humans take to maintain biodiversity.
- Breeding programmes for endangered species
- Protection and regeneration of rare habitats
- Reintroducing field margins and hedgerows on farmland
- Reducing deforestation and carbon dioxide emissions
- Recycling resources rather than dumping waste in landfill
Field margins
Strips of land around the edges of fields left to grow wild, which increase biodiversity by providing habitats for insects, wildflowers and other species.
Explain one conflicting pressure that makes maintaining biodiversity difficult.
Protecting biodiversity can be expensive or reduce food production — e.g. land used for field margins could instead grow crops, so farmers may need a subsidy to make up for lost income.
programmes are used to increase the numbers of endangered species and help maintain biodiversity.
Breeding programmes are used to increase the numbers of endangered species and help maintain biodiversity.
Why might governments pay farmers a subsidy to keep field margins and hedgerows?
The land used for margins and hedgerows could otherwise grow sellable crops, so a subsidy makes up for the farmer's lost income while protecting biodiversity.

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