Module 4: Conserving Biodiversity
These free OCR A Level Biology Conserving Biodiversity revision notes have been written for specification points 4.2.1(g), 4.2.1(h) and 4.2.1(i).
Conserving Biodiversity
Biodiversity provides essential resources, services, and benefits to ecosystems and human society. There are ecological, economic, and aesthetic reasons for protecting it.
Ecological Reasons
- Interdependence of species means that the loss of one species can affect many others.
- Keystone species have a disproportionately large effect on their ecosystem by supporting many species as a side effect of their behaviour.
- Genetic diversity provides natural variation that can be used to identify new medicines or produce new crops more resistant to drought or disease.
Economic Reasons
- Soil depletion caused by monoculture can lead to lower crop yields, requiring fertiliser and reducing long-term sustainability.
- Biodiversity supports ecotourism and recreation industries.
Aesthetic Reasons
- Natural environments have cultural, spiritual, and recreational value.
- Landscapes with high biodiversity are more attractive and can improve human well-being.
Conservation Methods: In Situ and Ex Situ
Conservation can be carried out in situ or ex situ. Each approach has advantages and limitations.
In Situ Conservation
This involves protecting species in their natural environment.
In situ conservation typically revolves around designating areas as a type of wildlife reserve to protect habitats and the species that live there.
The table below outlines the types of wildlife reserves:
| Method | Actions |
|---|---|
| In General | |
| Wildlife reserves |
– Designated to protect habitats and species from human interference and activity. – Preserves existing traditional use of the land (e.g. spiritual and hunting purposes). – Cooperate with local people to manage issues such as animal-human conflict over agriculture, logging and poaching. |
| Specific (UK) Types | |
| SSSI | Sites of Special Scientific Interest protect rare, vulnerable or highly biodiverse areas with an emphasis on conservation and research. |
| LNR | Local Nature Reserves are designated by local authorities as important areas for conservation work. |
| Marine conservation zone | Protect marine biodiversity by restricting fishing, oil drilling, and tourism. |
| National Park | Emphasise the aesthetic protection of UK landscapes for the access, enjoyment and use of everyone. |
| NNR | National Nature Reserves protect vulnerable environments for research and public education. |
Ex Situ Conservation
This involves protecting species by removing part of the population from a threatened habitat and placing it in a controlled environment.
The table below outlines the main approaches to ex situ conservation:
| Method | Actions |
|---|---|
| Zoo/Wildlife Park |
– Breed endangered animals in captivity, using artificial insemination, IVF and embryo transfer. – Educate the public. – Research into endangered species. |
| Botanic gardens |
– Grow rare or endangered plants. – Research plants and educate the public about them. – Collect and store seeds for easy long-term conservation at scale. |
| Seed banks | Long-term storage and distribution of seeds for agricultural, conservation, research and humanitarian work. |
Conservation Agreements
Conservation agreements help coordinate efforts to protect endangered species and ecosystems through shared objectives, legislation, and funding.
International agreements address conservation issues which are global and cross international borders; CITES (1973) and the CBD (1992) are two examples.
| Agreement | Purpose |
|---|---|
| CITES | The Convention on International Trade in Endangered Species of Wild Fauna and Flora is an international agreement that regulates and monitors the trade of over 25,000 species. |
| CBD | The Rio Convention on Biological Diversity promotes the conservation of biodiversity for the sustainable use of resources and sharing of research to the benefit of the communities from which organisms originate. |
*Examination materials typically provide the full name and abbreviation, and (so far) have tested candidates’ knowledge and understanding of the named agreement, instead of testing their ability to identify and name it.
National and local agreements address conservation issues in an entire country, particular regions, or types of habitat. The CSS (1991), and later the ESS (2005) in the UK are two example.
| Agreement | Purpose |
|---|---|
| CSS* | The Countryside Stewardship Scheme funds and supports farmers and landowners to promote biodiversity and heritage conservation. |
| ESS* | The Environmental Stewardship Scheme funds and supports farmers to conserve, enhance and promote the countryside. |
*Examination materials typically provide the full name and abbreviation, and (so far) have tested candidates’ knowledge and understanding of the named agreement, instead of testing their ability to identify and name it.
The endorsed OCR A level textbook indicates that the CSS was replaced by the ESS, whilst in reality both programs are still running.