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Reasons for the Conservation of Animal and Plant Species
(1) Economic
- Lose potential drugs - 80% of the world's medicines come from plants.
- Loss of fuels, food and drink, clothing and other industrial materials (e.g. paper)
(2) Ecological
- Disruption of food chains and nutrient cycles.
- Regulation of the climate and atmosphere - plants produce oxygen and remove CO2.
(3) Ethical
- Religious/spiritual reasons.
- Moral responsibility.
- Right to exist.
(4) Aesthetic
- Areas to enjoy for recreation.
- Ecotourism - wildlife tourism.
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.
When it comes to AS/A-level Biology, do you notice the consequences of climate change on biodiversity with reference to changing patterns of agriculture and spread of disease?
Consequences of Climate Change on Biodiversity
- 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:
(i) major human developments
(ii) agricultural land
(iii) large bodies of water
(iv) 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.
Agriculture
Advantages:
- Grow a variety of different crops in the same country = increases biodiversity
- Longer growing seasons as it is warmer for longer
- Higher CO2 levels = more photosynthesis
- Greater evaporation of water = greater precipitation
Disadvantages :
- Loss of land due to rise in sea level = increased salinity of the soil
- A change in the distribution of precipitation
- Introduces new pests and diseases = lower yields
Spread of Disease
- Crops being grown in new areas will encounter new diseases and pests.
- These crops will not have resistance to these specific diseases and pests.
- Higher temperatures means more species of pests and diseases are able to survive and overwinter successfully and cause greater infestations earlier in the year, meaning lower yields and less food for humans.
- Human diseases will also migrate.
- Tropical diseases that thrive in the warmth and moisture of the tropics may become a problem in Europe.
- Anopheles mosquitoes that carry malaria may be able to live in new areas, causing the spread of diseases to new areas.
That's the end of the topic!
Drafted by Bonnie (Biology)