5.3.11Unit 5: Respiration, Internal Environment, Coordination and Gene Technology
Examples of Sustainable Conservation — IAL Edexcel Linear Revision Notes & Topical Questions
5 min read 5 parts Lesson 25 of 36 Unit quiz
Section 1 of 5What Sustainability Means
Definition
- Sustainable use of resources meets present needs without damaging the environment or preventing future generations from meeting theirs.
The problem
- Modelling shows that continuing current activities could seriously harm people and biodiversity.
Two aims
- Strategies either reduce carbon emissions or increase the rate at which carbon is removed from the atmosphere.
Difficulty
- Cutting fossil fuel use is hard because transport, electricity and food production all depend on it.
Section 2 of 5Biofuels
Biofuels
What they are
- Biofuels are fuels made from recently living plant material, such as sugar cane, and they release carbon dioxide when burned.
Carbon neutral argument
- They are described as carbon neutral because the carbon released was recently taken from the air by the growing plants.
Other advantages
- They are renewable because crops can be regrown quickly, and they are often cheaper than oil.
Disadvantages
- They still release carbon dioxide, and the land used could have grown food or been natural habitat.
Forest clearance
- Clearing mature forest to grow fuel crops removes habitats and reduces carbon uptake by photosynthesis.
Section 3 of 5Other Renewable Energy Sources
Wind
- Turbines release no carbon dioxide in use but depend on wind speed, and some people worry about harm to birds and bats.
Solar
- Solar power depends on hours of sunshine, but the technology is becoming cheaper and more efficient.
Geothermal
- This can only be used where volcanic activity brings heat close to the surface.
Tidal
- Tidal energy is limited to coastal sites where tides are strong.
| Source | Advantage | Limitation |
|---|---|---|
| Biofuel | Renewable, near carbon neutral | Land use, habitat loss |
| Wind and solar | No carbon dioxide released in use | Depend on weather |
| Geothermal and tidal | Reliable, low emissions | Only available in certain places |
Section 4 of 5Increasing Carbon Removal
1
Technology able to remove large amounts of carbon from the air and store it does not yet exist at the scale needed.
2
The main current method of removal is photosynthesis, so protecting plants is essential.
3
Halting deforestation keeps existing trees storing carbon and photosynthesising.
4
Reforestation, planting new trees, adds biomass that stores carbon as the trees grow to maturity.
5
Large-scale forest restoration needs government support, such as benefits for landowners.
Section 5 of 5Exam Checklist & Tips
5.3.11 – Key Points for the Exam
- Sustainability Using resources in a way that can be maintained for future generations without environmental damage.
- Biofuel A fuel made from recently living plant material.
- Renewable A resource that is replaced as fast as it is used or can be regrown quickly.
- Reforestation Planting trees to restore forest.
Common Mistakes
- Calling biofuels carbon free;
- they release carbon dioxide and are only near carbon neutral if replacement crops absorb it.
- Ignoring the land use argument, which is the most common valid criticism of biofuel crops.
- Saying wind and solar release no carbon dioxide at all;
- they release none in operation, though making them uses energy.
- Relying on future carbon capture technology to solve the problem when it is not available at scale.
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