Habitat Destruction
Overview
When a forest is felled or a wetland drained, far more is lost than trees or water. Every habitat is a web of living things that depend on one another, so destroying it can topple species that never lived there directly. Habitat destruction is now the single biggest cause of falling biodiversity worldwide.
In this lesson you will define biodiversity, set out the main reasons habitats are destroyed, and see how disturbing a food web ripples outward. You will then work through deforestation as a detailed case study, explaining its undesirable effects: lost biodiversity, extinction, soil erosion, flooding and a build-up of carbon dioxide.
Objectives
- [Core] Describe an ecosystem as a unit containing the community of organisms and their environment, interacting together
- [Core] Describe biodiversity as the number of different species that live in an area
- [Core] Describe the reasons for habitat destruction, including: (a) increased area for housing, crop plant production and livestock production (b) extraction of natural resources (c) freshwater and marine pollution (a detailed description of eutrophication is not required)
- [Core] State the undesirable effects of deforestation as an example of habitat destruction, to include: reducing biodiversity, extinction, loss of soil, flooding and increase of carbon dioxide in the atmosphere
- [Supplement] Explain the undesirable effects of deforestation as an example of habitat destruction, to include: reducing biodiversity, extinction, loss of soil, flooding and increase of carbon dioxide in the atmosphere
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Habitat Destruction. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- Biodiversity is defined as: A. the total number of animals in an area B. the number of different species that live in an area C. the size of the largest population D. the number of food chains Answer: B
- Which is NOT a direct effect of deforestation? A. soil erosion B. increased carbon dioxide C. increased biodiversity D. flooding Answer: C
- Deforestation increases atmospheric carbon dioxide mainly because: A. trees release carbon dioxide while alive B. fewer trees remove carbon dioxide by photosynthesis C. soil absorbs carbon dioxide D. rivers flood Answer: B
- Removing tree roots from a hillside leads to: A. less rainfall B. soil erosion and flooding C. higher biodiversity D. more nutrients in the soil Answer: B
- A reason for habitat destruction is: A. planting hedgerows B. extraction of natural resources C. creating nature reserves D. captive breeding Answer: B
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