Water Sources And Supply
Aperçu
Turn on a tap and clean water flows out, as if by magic. Yet that water has travelled an extraordinary journey: it may have evaporated from a tropical ocean, drifted as cloud across a continent, fallen as rain on a distant hill, soaked deep into rock and waited there for years before being pumped to your home. Understanding where fresh water comes from, and why some people have far too little of it, is one of the most important ideas in environmental management.
In this lesson you will follow water around its endless cycle, meet the four great sources humans draw on, and learn how raw water is treated until it is safe to drink. You will weigh up desalination plants and multipurpose dams, the giant engineering projects that bring water to dry lands, and see why a country that is rich in rainfall is not always rich in water for its people.
Objectifs
- 3.1.1 Describe and interpret the water cycle, limited to: (a) stores: salt water (oceans) and fresh water (ice sheets and glaciers, ground water, atmosphere and lakes and rivers) (b) transfers: precipitation, interception, surface run-off, infiltration, through-flow, ground water flow, transpiration, evaporation and condensation.
- 3.1.2 Describe the sources of fresh water used by people, limited to: (a) atmosphere: rain and snow (b) surface water: rivers, lakes and reservoirs (c) ground water: aquifers and wells (d) oceans: desalination plants.
- 3.1.3 Identify the world’s oceans: Pacific, Atlantic, Indian, Southern and Arctic.
- 3.1.4 Define potable water as water that is safe to drink.
- 3.1.5 Describe the stages in water treatment to make water potable, limited to: (a) screening (b) sedimentation (c) filtration (d) chlorination.
- 3.1.6 Compare the availability of potable water in different parts of the world, limited to: (a) water-rich and water-poor regions (b) urban and rural regions (c) global inequalities in water availability and sewage treatment.
- 3.1.7 Describe the process of desalination, limited to: (a) distillation: water heated until it boils, salt remains in the liquid, steam is pure water, steam is cooled and condensed to form potable water (b) reverse osmosis: water is put under high pressure, passed through a membrane, membrane allows water molecules to pass through but stops most ions and other molecules.
- 3.1.8 Discuss the benefits and limitations of desalination.
- 3.1.9 Describe the uses of a multipurpose dam, limited to: (a) flood control (b) hydro-electric power (c) irrigation (d) storage of water (e) transport (f) recreation (g) tourism (h) fish farming.
- 3.1.10 Discuss the benefits and limitations of a multipurpose dam.
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Évaluation de la leçon
Félicitations, vous avez terminé la leçon sur Water Sources And Supply. Maintenant que vous avez exploré le concepts et idées clés, il est temps de mettre vos connaissances à l'épreuve. Cette section propose une variété de pratiques des questions conçues pour renforcer votre compréhension et vous aider à évaluer votre compréhension de la matière.
Vous rencontrerez un mélange de types de questions, y compris des questions à choix multiple, des questions à réponse courte et des questions de rédaction. Chaque question est soigneusement conçue pour évaluer différents aspects de vos connaissances et de vos compétences en pensée critique.
Utilisez cette section d'évaluation comme une occasion de renforcer votre compréhension du sujet et d'identifier les domaines où vous pourriez avoir besoin d'étudier davantage. Ne soyez pas découragé par les défis que vous rencontrez ; considérez-les plutôt comme des opportunités de croissance et d'amélioration.
- Which transfer in the water cycle describes water seeping into the soil? A. evaporation B. infiltration C. condensation D. transpiration Answer: B
- Potable water is water that is: A. found in the ocean B. used only for irrigation C. safe to drink D. stored in an aquifer Answer: C
- Which is the correct order of water treatment stages? A. chlorination, filtration, sedimentation, screening B. screening, sedimentation, filtration, chlorination C. filtration, screening, chlorination, sedimentation D. sedimentation, chlorination, screening, filtration Answer: B
- In reverse osmosis, salt water is made potable by: A. boiling it and condensing the steam B. adding chlorine C. pushing it through a membrane under high pressure D. letting particles settle out Answer: C
- Which is a benefit of a multipurpose dam? A. it traps fertile silt B. it blocks fish migration C. it generates hydro-electric power D. it floods farmland Answer: C
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Livres recommandés
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Section de manuel
Biogeochemical Cycles
Discuss the biogeochemical cycles of water, carbon, nitrogen, phosphorus, and sulfur
"Biology: Biogeochemical Cycles" by OpenStax, OpenStax, Rice University, licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source: https://openstax.org/books/biology/pages/46-3-biogeochemical-cycles. Access for free at https://openstax.org/books/biology/pages/1-introduction
Publiées par d'autres organisations sous licence libre, créditées comme elles le demandent. Les liens ouvrent leurs sites.
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