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1、1 of 45 Boardworks Ltd 20062 of 45 Boardworks Ltd 2006B2h Sustainability1.Describe reasons why animals become extinct / endangered: climate change, habitat destruction, hunting, pollution and competition Describe how endangered species can be helped: protecting habitats legal protection education pr
2、ogrammes captive breeding programmes creating artificial ecosystems (higher tier) Discuss reasons for conservation programmes: protecting human food supply ensuring minimal damage to food chains future identification of plants for medical purposes cultural aspects2.State that whales have commercial
3、value: tourism when alive; food, oil and cosmetics when dead Consider issues arising from keeping whales in captivity: entertainment, research, captive breeding programmes (higher tier) State that some aspects of whale biology are still not fully understood: communication, migration patterns and sur
4、vival at extreme depths Discuss problems of whaling: getting international agreement, policing laws and culling for research3. Explain the term sustainable development Explain how fish stocks and woodland can be sustained and yet exploited: education quotas on fishing re-plantation of woodland (high
5、er tier) Discuss the importance of population size, waste products and food and energy demands to sustainable development Recognise that sustainability requires planning and cooperation at local, national, and international levels Describe how sustainable development may protect endangered species3
6、of 45 Boardworks Ltd 20064 of 45 Boardworks Ltd 2006Sustainability, or sustainable development, is the ability to provide for the needs of the present without affecting the ability of future generations to provide for themselves.What is sustainability?In the long-term, environmental degradation will
7、 result in an ecosystem that cannot support humans or other organisms.A major aim of sustainable development is preventing environmental degradation. This is a process where natural resources such as plants, animals, water and fuel are consumed more quickly then they are replaced. 5 of 45 Boardworks
8、 Ltd 2006What are ecological footprints?An ecological footprint is the amount of land and water that is needed to produce all the food, energy and products that a typical person uses.Ecological footprints are measured in hectares. One hectare is 10,000 m2, or about the size of a large football pitch
9、.The smaller the footprint, the lower the impact on the environment.6 of 45 Boardworks Ltd 2006Sustainable footprintsThe Worldwide Fund for Nature recommends that footprints need to be less than 2 hectares per person to avoid damaging the environment and wildlife.How can ecological footprints be red
10、uced?l recycling materials such as paper, glass, plastic, metal and wood.l using sustainable products, such as organic food and wooden furniture from sustainable forestsThe productive capacity of Earth is 11.4 billion hectares, and the average European ecological footprint is 5 hectares per person.7
11、 of 45 Boardworks Ltd 2006Comparing footprints8 of 45 Boardworks Ltd 2006Lack of sustainability threatens many organisms with extinction. This occurs when the last individual of a species dies.Countdown to extinctionOver 1.5 million different species of organisms have been identified, but scientists
12、 think there are many millions still to be discovered.However, extinction rates are the highest since the death of the dinosaurs. On average, one species of plant or animal becomes extinct every 20 minutes.9 of 45 Boardworks Ltd 2006Non-sustainable developmentWhat will happen if sustainable developm
13、ent fails? 10 of 45 Boardworks Ltd 2006Why does extinction happen?l destruction of natural habitatsl over-huntingl climate changel pollution.Extinction has always taken place, even before humans evolved. For example, the dinosaurs are thought to have became extinct due to a comet striking the Earth.
14、How does human activity cause extinction?Do you know of any extinct species?11 of 45 Boardworks Ltd 2006When a species is at risk of extinction, it is endangered.What is an endangered species?Over 1,100 animal species and over 700 plant species are classed as endangered or threatened.l giant pandal
15、gorillal blue whale.l snow leopardl California condorAnimals that are endangered or threatened include the:12 of 45 Boardworks Ltd 2006Wildlife tradeIn the 1990s, over $160 billion worth of meat, skins, furs and traditional Chinese medicine were imported around the world each year.l Harm to humans o
16、verexploitation of a species can leave people with no food in countries where rural households depend on local wild plants and animals. l Harm to wildlife killing wildlife can unbalance entire food chains and lead to the death of other species.Some types of wildlife trade are legal but the killing of a protected species is not.What harm does wildlife trade cause?13 of 45 Boardworks Ltd 2006Forests cover 10% o
