Maintaining biodiversitySpec 4.7.3.6
Human interactions in an ecosystem can be negative or positive. You need to describe both and explain their impact on biodiversity.
| Negative interactions | Positive interactions |
|---|---|
| Building, quarrying, farming and dumping waste reduce the land available | Breeding programmes for endangered species |
| Pollution of water, air and land | Protection and regeneration of rare habitats |
| Destroying peat bogs and clearing forest | Reintroduction of field margins and hedgerows in agricultural areas where farmers grow only one type of crop |
| Releasing more carbon dioxide and methane | Reduction of deforestation and carbon dioxide emissions by some governments |
| Dumping waste in landfill | Recycling resources rather than dumping waste in landfill |
Scientists and concerned citizens have put in place programmes to reduce the negative effects of humans on ecosystems and biodiversity.
| Programme | How it helps biodiversity |
|---|---|
| Breeding programmes for endangered species | Increase the numbers of a species so it does not die out |
| Protection and regeneration of rare habitats | Keeps the habitat and the species that depend on it |
| Reintroducing field margins and hedgerows | Gives shelter and food for wildlife in fields where only one crop grows, so more species can live there |
| Reducing deforestation and carbon dioxide emissions | Protects forest habitats and slows global warming |
| Recycling instead of landfill | Uses less land for dumping waste and reduces pollution |
Conflicting pressures
Maintaining biodiversity is not always easy. There are conflicting pressures. Farmers want land for crops and animals, people need food, fuel and homes, and conservation costs money. Reducing emissions or protecting habitats may reduce profits or jobs.
Quick check
Define biodiversity.
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The variety of all the different species of organisms on Earth, or within an ecosystem.
Name three ways humans reduce the land available for other organisms.
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Any three of: building, quarrying, farming, dumping waste.
Why does destroying peat bogs add to global warming?
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The decay or burning of peat releases carbon dioxide into the atmosphere.
Which two gases are increasing in the atmosphere and contributing to global warming?
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Carbon dioxide and methane.
Give two programmes that help maintain biodiversity.
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Any two of: breeding programmes, protecting rare habitats, hedgerows and field margins, reducing deforestation and emissions, recycling.