Maintaining Biodiversity
(a) outline the reasons for the conservation of animal and plant species, with reference to economic, ecological, ethical and aesthetic reasons
How are humans reducing biodiversity?
- Disruption of food chains – over-harvesting
- Killing to remove competitors for our food – using pesticides to kill insects, fungi and other pests
- Pollution – especially industrial pollution causing climate change
- Habitat destruction – e.g. deforestation for agriculture
- Inadvertent introduction of new predators and competition to areas
- Killing for protection – attempting to kill insects that are vectors of disease (e.g. Anopheles mosquitoes) or to remove the threat of a predator
- Agriculture – only harvesting one species (monoculture) creates a low species diversity
(b) discuss the consequences of global climate change on the biodiversity of plants and animals, with reference to changing patterns of agriculture and spread of disease
Climate change has a major impact on the biodiversity of plants and animals. As the climate changes, species that have lost their genetic variation and are unable to evolve, will be unable to adapt to the changes in temperature and rainfall in the area where they live. The only alternative for them is to migrate. However, there will be obstructions to this migration:
- major human developments
- agricultural land
- large bodies of water
- humans
For example, the golden toad of the Costa Rican cloud forest moves uphill as the climate warms up to stay in the most suitable habitat. However when it reaches the top of the hill it has nowhere to go. Therefore this species is becoming extinct as the climate changes.
(c) explain the benefits for agriculture of maintaining the biodiversity of animals and plant species
Allowing biodiversity to increase means that genetic diversity also increases. Wild animals and plants may hold the answer to problems caused by climate change as they have adapted to overcome the problems presented by the environment over many years as well as pests and disease. By careful selection and breeding from wild species, we may be able to breed new crop varieties that can cope with the new conditions created by climate change. Genetic engineering to produce transgenic species can be used.
The number of potential new medicines and the range of possible vaccines that could be developed from wild plants and microorganisms is unknown. It’s important to maintain genetic diversity of wild plants and animals because of the potential that exists in the wide range of species currently alive.
(d) describe the conservation of endangered plant and animals species, both in situ and ex situ, with references to the advantages and disadvantages of these two approaches
(e) discuss the role of botanic gardens in the ex situ conservation of rare plant species or plant species extinct in the wild, with reference to seed banks
(f) discuss the importance of international co-operation in species conservation with reference to The Convention in International Trade in Endangered Species (CITES) and the Rio Convention on Biodiversity
(g) discuss the significance of environmental impact assessments (including biodiversity estimates) for local authority planning decisions