1. Берстенова А. Б. Ағылшын тілі пәні бойынша : I-II курс студ арн практикалық сабақтардың әдістемелік нұсқаулары / А. Б. Берстенова, А. А. Байжанова, А. А. Батинова, 2014
Renewable and non-renewable resources
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- Бұл бет үшін навигация:
- Renewable resources.
- Non-renewable resources.
| 1. 2. Renewable and non-renewable resources
Natural resources can be categorized as either renewable or non-renewable. Renewable resources are replaced naturally and can be used over and over again. Non-renewable resources, however, are almost impossible to replace and their supplies lessen with each use. Renewable resources. For many years people thought that water was one of the most abundant natural resources. Scientists regard water as a renewable resource because it is constantly recirculated by the water cycle. However, water is a fragile resource. Water re-entering the water cycle often carries traces of fertilizers, pesticides, industrial chemicals, and sewage. These contaminants pollute the water and can destroy its value as a resource. Forests are renewable resources if people plant new trees to replace those cut down. Fish and wildlife are renewable resources if people leave enough fish and wildlife to reproduce and ifthey preserve natural habitats. Perhaps the natural resource that people most take for granted is soil. But even soil must be protected to remain a valuable resource. Soil has three general levels. Decayed plants and animals, or humus, make up the top level. Soil rich in humus is usually fertile and is black or dark brown. Below the humus lies a layer of mineral particles that washes down from the humus. Finally, there is a layer of parent material, or solid rock. The weathering of this rock forms most of the soil. Clearing the land of its natural vegetation encourages soil erosion. Farming the same crops in the soil depletes it of valuable minerals. Irrigating the soil can result in salinization, or a salt build-up that eventually destroys the soil's productivity. For these and other reasons, scientists consider soil to be a renewable resource only if people take measures to prevent erosion, grow plants that restore nutrients, or use natural or chemical fertilizers. Non-renewable resources. Such important resources as coal, oil, natural gas, iron ore, copper, bauxite (the principal source of aluminum), gold, and silver are non-renewable resources. As people use these resources, they cannot be replaced. Resource depletion can be slowed through recycling. Recycling is the process by which products that have been used and discarded can be reused. Conservationists, people who work to protect natural resources and natural environments, support recycling because it slows the use of the earth's resources. Paper, which is made from trees, is one of the most commonly recycled materials. Youth groups and charitable organizations often collect newspapers and other paper products to sell to recycling factories. The factories grind up the old paper and make it into new paper. Many greeting cards, for example, are printed on recycled paper. Recycling paper saves millions of trees each year. 1. What is the difference between renewable and non-renewable resources? 2. In order to be classified as a renewable resource, what steps must be taken to protect the soil? 3. Why do many people favor recycling? жүктеу/скачать 25,52 Kb. Достарыңызбен бөлісу:
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