They go from one place to another, and often back where they started, again and again. This is a good thing, because all living things need air and water to survive. There is one other type of renewable natural resource. It includes sources of power like sun and wind energy. These are never ending. Finally, remember this: renewable resources can regrow or be replaced within a person's lifespan. Nutrients are chemicals that living things need.
They are renewable natural resources. They move round and round in cycles and never run out. When an animal like this cow eats a plant, it takes in nutrients. The nutrients are used in the animal's body and then many come out as waste, which returns the nutrients to the soil. When the animal dies, nutrients will return to the soil as well.
Plants take up the nutrients in the soil and continue the cycle. Now, let's look at nonrenewable natural resources. They are found in the ground.
There are fixed amounts of these resources. They are not living things, and they are sometimes hard to find.
They don't regrow and they are not replaced or renewed. They include the fossil fuels we burn for energy natural gas, coal, and oil. Minerals, used for making metals, are also nonrenewable natural resources. Nonrenewable natural resources are things that take longer than a person's lifespan to be replaced. In fact, they can take millions of years to form. Fossil fuels such as oil, coal, and gas will not last forever. They are nonrenewable. People are trying hard to find new fuels that are clean and will provide the power we need.
Wind, solar, and hydrogen power are renewable resources that offer hope for the future. People use both types of natural resources to produce the things they need or want. Our homes, clothing, plastics, and foods are all made from natural resources.
Let's look at each one of these to be sure. Your home is in a building. Buildings are made out of wood and minerals.
Wood is from trees. Minerals are mined from the ground. Bricks, cement, and metals are made from minerals. How about your clothes? Most of your clothing is made from cotton, polyester, or nylon. Discuss the practical applications of regrowth mechanisms. References Fertilization Overview Pre-Test Instructional Objectives Discuss the importance of soil fertility and the appropriate use of fertilization.
Define and discuss the nitrogen cycle. Discuss the major elements needed for good soil fertility and plant growth. Define and discuss micronutrients. Discuss the uses and methods of liming. Discuss fertilizer management for mixed stands.
Describe the benefits of BNF in economic and environmental terms. Estimate the amount of BNF that is contributed by various crops.
List and discuss factors that affect the quantity of nitrogen fixed. Describe the processes of infection and nodulation in forage legumes. Describe the process of inoculation in the production of forage legumes. List and discuss the types of grazing. Compare and contrast the different types of grazing. Discuss the livestock dynamics on pastures and grazing.
Discuss the utilization of a yearly grazing calendar. List the characteristics of good hay and the steps needed to make it. Determine the characteristics of good silage and the steps in producing it. Discuss the potential dangers in mechanically harvesting and storing forages. Compare and contrast the types of storage and discuss the advantages and disadvantages of each.
Describe major types of irrigation systems in US forage production. List and discuss factors that affect irrigation efficiency. Describe basic principles of scheduling irrigation for efficient use of water resources. Describe potential problems that may arise from the use of irrigation in forages. The energy to run machinery and processing facilities is obtained by burning fossil fuels, particularly natural gas, so the industry is a major emitter of greenhouse gases.
The oil-sand industry has voluntarily committed to major investments in improved technology to decrease their intensity of energy use and CO2 emissions see Canadian Focus By decreasing the energy intensity of their operations, the industry will emit smaller amounts of greenhouse gases per tonne of bitumen and synthetic that they produce.
Nevertheless, because of the rapidly increasing scale of oil-sand operations in northern Alberta, there will be a large increase in the total amount of emissions. In fact, the growth of the oil-sand industry is responsible for most of the increase in Canadian emissions of greenhouse gases over the past decade or so. There are additional important environmental effects of the mining and processing of oil sands. They include pollution of the atmosphere, groundwater, and surface water; the extensive destruction of natural habitats; and socio-economic disruptions of rural and Aboriginal communities.
In the larger context, however, these damages must be viewed as an inevitable result of the apparent enthusiasm of Canadian society, politicians, and business interests to mine, sell, and use fossil-fuel resources at a rapid and non-sustainable rate. This is happening because of the perceived importance of these activities to the domestic and export economies of Canada. Other materials that are mined in large quantities in Canada include asbestos, diamonds, gypsum, limestone, potash, salt, sulphur, aggregates, and peat.
Except for diamonds, these materials have a smaller commodity value value per tonne than metals and fossil fuels. Global or Canadian shortages of these materials are not imminent. Asbestos refers to s a group of tough, fibrous, incombustible silicate minerals that are used to manufacture fireproof insulation, cement additives, brake linings, and many other products.
However, certain kinds of asbestos minerals have been linked to human health problems, particularly lung diseases. These hazards have greatly reduced the market for this otherwise useful mineral. As recently as about 0. Diamonds are relatively new to the mining scene in Canada, with the first major discoveries not made until the s. About Almost all mining occurs in the Northwest Territories, with some also in Ontario, and with exploration elsewhere on the Canadian Shield.
Gypsum , a mineral composed of calcium sulphate, is used to manufacture plaster and wallboard for the construction industry. About 2. All gypsum mining occurs in Nova Scotia. Limestone is a rock composed of calcium carbonate.
It is used to manufacture cement, as well as lime for making plaster. In addition, some limestone, and the related metamorphic rock known as marble, is quarried for use as building stone and facings. About million tonnes of limestone were mined in It was used to make Another 1.
Ontario, Quebec, and British Columbia have the largest cement industries, and Ontario the largest lime-making capacity. Potash is a rock formed from the mineral potash feldspar, and it is mined to manufacture potassium-containing fertilizer. Potash is mined in Saskatchewan and New Brunswick.
Sulphur is manufactured from hydrogen sulphide obtained from sour-gas wells gas wells rich in H 2 S , from pollution-control scrubbers for SO 2 at metal smelters, and from deposits of native or elemental sulphur. Sulphur is used in the chemical manufacturing industries and to make fertilizer. About 6. Aggregates include sand, gravel, and other materials that are mined for use in road construction and as fillers for concrete in the construction industry.
Aggregates are a low-grade resource, having relatively little value per tonne. However, these materials may be available only in small quantities close to large cities, leading to local shortages.
These materials are mined in all provinces and territories, at rates more or less related to the local construction activity. Peat is a sub-fossil material that has developed from dead plant biomass that is hundreds to thousands of years old. It accumulates in bog wetlands, where it becomes partially decomposed or humified. Peat is sometimes dried and burned as a source of energy, an important use in Ireland, parts of northern Europe, and Russia.
In Canada, however, peat is mined for use as a horticultural material and to produce absorbent hygienic products such as diapers and sanitary napkins. About 1. Most peat mining occurs in New Brunswick and Quebec. It is critical for any economy to have ready access to relatively inexpensive and accessible sources of energy for commercial, industrial, and household purposes.
The use of large amounts of energy is especially characteristic of developed countries, such as Canada. As has been examined previously, relatively wealthy, developed countries use much more energy on a per-capita basis than do poorer, less-developed countries. Ever since people achieved a mastery of fire, they have used fuels for subsistence purposes, that is, to cook food and to keep warm.
Initially, locally collected wood and other plant biomass were the fuels used for those purposes. Perhaps only one-million people were alive when fire was first domesticated, and their per-capita energy use was small.
Consequently, biomass fuels were a renewable source of energy because the rate at which they were being harvested was much smaller than the rate at which new biomass was being produced by vegetation. In modern times, however, the human population is enormously larger than it was when fire was first put to work.
Moreover, many countries now have intensely industrialized economies in which per-capita energy usage is extremely high. The combination of population growth and increased per-capita energy use means that enormous amounts of energy are used in developed countries.
The energy is needed to fuel industrial processes, to manufacture and run machines, to keep warm in winter and cool in summer, and to prepare food. Most industrial energy supplies are based on the use of non-renewable resources, although certain renewable sources may also be important. For comprehensiveness, both non-renewable and renewable energy sources are discussed together in this section. Hydroelectric power, generated using the renewable energy of flowing water, is also important in some regions, including much of Canada.
Any of the above sources can be harnessed to drive a turbine, which spins an electrical generator that converts the kinetic energy of motion into electrical energy. Solar energy can also generate electricity more directly, through photovoltaic technology see below. Electricity is one of the most important kinds of energy used in industrial societies, being widely distributed to industries and homes through a network of transmission lines. The following sections briefly describe how these various energy sources are used.
Electricity generated by sing nuclear fuel or by burning coal, oil, or natural gas uses non-renewable sources of energy. Coal, natural gas, petroleum, and their refined products can be combusted in power plants, where the potential energy of the fuel is harnessed to generate electricity. Fossil fuels are also combusted in the furnaces of many homes and larger buildings to provide warmth during colder times of the year. The burning of fossil fuels has many environmental drawbacks, including emissions of greenhouse gases, sulphur dioxide, and other pollutants into the atmosphere.
Nuclear fuels contain unstable isotopes of the heavy elements uranium and plutonium U and Pu, respectively. These can decay through a process known as fission, which produces lighter elements while releasing neutrons per nucleus and an enormous quantity of energy.
The emitted neutrons may be absorbed by other atoms of U or Pu, causing them to also become unstable and undergo fission in a process known as a chain reaction. An uncontrolled chain reaction can result in a devastating nuclear explosion. In a nuclear reactor, however, the flux of neutrons is carefully regulated, which allows electricity to be produced safely and continuously.
Nuclear reactions are fundamentally different from chemical reactions, in which atoms recombine into different compounds without changing their internal structure. In nuclear fission, the atomic structure is fundamentally altered, and small amounts of matter are transformed into immense quantities of energy. Most of the energy liberated by nuclear fission is released as heat.
In a nuclear power plant, some of the heat is used to boil water. The resulting steam drives a turbine, which generates electricity. Most nuclear-fuelled power plants are huge commercial reactors that produce electricity for industrial and residential use in large urban areas Image Smaller reactors are sometimes used to power military ships and submarines, or for research.
Canada is a major player in uranium mining, most of which is exported; see Table Uranium produced by refining ore typically consists of about Various elements, most of which are also radioactive such as radon gas , are produced during fission reactions. One of these, Pu, can also be used as a component of nuclear fuel in power plants.
To obtain Pu for this purpose or for use in manufacturing nuclear weapons , spent fuel from nuclear generating stations is reprocessed. Other trans-uranium elements and any remaining U as well as non-fissile U can also be recovered and be used to manufacture new fuel for reactors. So-called fast-breeder reactors are designed to optimize the production of Pu which occurs when an atom of U absorbs a neutron to produce U, which then forms Pu by the emission of two beta electrons.
Although fast-breeder reactors have been demonstrated, they have not been commercially developed. However, there are limits to the process because the original quantity of U is eventually depleted. Therefore, both U and Pu should be considered to be non-renewable resources. A number of important environmental problems are associated with nuclear power.
These include the small but real possibility of a catastrophic accident such as a meltdown of the reactor core, which can result in the release of large amounts of radioactive material into the environment as happened at the Chernobyl reactor in Ukraine in Nuclear reactions also produce extremely toxic, long-lived radioactive by-products such as plutonium , which must be safely managed for very long periods of time up to tens of thousands of years.
Fusion is another kind of energy-producing nuclear reaction. This process occurs when light nuclei are forced to combine under conditions of extremely high temperature millions of degrees and pressure, resulting in an enormous release of energy. Fusion usually involves the combining of hydrogen isotopes.
One common fusion reaction involves two protons two hydrogen nuclei, 1 H fusing to form a deuterium nucleus composed of one proton and one neutron, 2 H , while also emitting a beta electron and an extremely large amount of energy.
Fusion reactions occur naturally in the interior of the Sun and other stars, and they can also be initiated by exposing hydrogen to the enormous heat and pressure generated by a fission nuclear explosion, as occurs in a so-called hydrogen bomb. However, nuclear technologists have not yet designed a system that can control fusion reactions to the degree necessary to generate electricity in an economic system.
If this technology is ever developed, it would be an enormous benefit to industrial society. It would mean that virtually unlimited supplies of hydrogen fuel for fusion reactors could be extracted from the oceans, which would essentially eliminate constraints on energy supply. When you reach out to them, you will need the page title, URL, and the date you accessed the resource. If a media asset is downloadable, a download button appears in the corner of the media viewer.
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Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. However, over time, there has been a shift in demand for cheaper and cleaner fuel options, such as the nonrenewable energy source of natural gas, and renewable options like solar power and wind energy. Each energy resource has its advantages and disadvantages.
Explore nonrenewable and renewable options with this collection on energy resources. What is a fossil fuel and what is being done to make fossil fuels more environmentally friendly? Fossil fuels form from the remains of prehistoric dead animals and plants due to geologic processes. Non-renewable energy comes from sources that will eventually run out, such as oil and coal. Join our community of educators and receive the latest information on National Geographic's resources for you and your students.
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