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Geologist Marion King Hubbert noted a bell-shaped curve in the use of resources, now commonly called the “Hubbert curve” and often used in estimates of resource use and reserves. (Hubbert first applied his curve to petroleum in the late 1940’s and subse- quently reviewed and amended his prediction a num- ber of times.) According to the Hubbert curve, a re-...
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Several such systems are in operation in the United States. In spite of the technical and economic viability of pumped hydro, the require- ment of a specific type of topography and some envi- ronmental concerns limit its application. Solar Heat Storage. When converted into heat, solar energy can be stored in the form of sensible heat and latent heat. The...
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Meter, cubic Volume/capacity m 3 1.308 cubic yards. Microgram Mass/weight mcg or µg 0.000001 gram. Microliter Volume/capacity µl 0.00027 fluid ounce. Milligram Mass/weight mg 0.015 grain. Milliliter Volume/capacity ml 0.271 fluid dram. Mass/weight oz 28.350 grams. Mass/weight oz 31.103 grams. Mass/weight oz 1.805 cubic inch. Peck Volume/capacity pk 8.810 liters. Volume/capacity pt 33.600 cubic inches. Volume/capacity pt 28.875 cubic inches....
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Global Resources. Environment and Natural Resources Division. The Environment and Natural Resources Division of the U.S. Department of Justice litigates cases rang- ing from the protection of endangered species to the cleaning up of hazardous waste sites. In other words, it serves as the nation’s environmental lawyer.. It enforces civil and criminal environmental laws to protect human health and the...
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A third area of resource exploitation that is useful to review in the context of environmental degradation is forests. At the time that European settlers began to ex- ploit the resources of the United States, forests cov- ered about two-thirds of the land. To many of the early settlers, these forests seemed endless, so cutting, burning, and re- moval went...
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“Superfund” because of the trust fund created by the act to fund cleanups, CERCLA is a comprehensive ap- proach to hazardous chemical dump and spill sites. It authorizes the president of the United States, through the EPA, to clean up facilities at which haz- ardous substances have been released. Petroleum substances not otherwise contaminated or listed as hazardous are exempted...
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Environmental law in the United States. Erosion is the gradual wearing away of the land sur- face by natural agents of water, wind, and ice. The land is de- graded because the soil that remains is of lower produc- tivity, and the sediment may damage crops or aquatic. Erosion also causes the soil to be less productive because the remaining...
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der the jurisdiction of the coastal state for specific purposes. The convention, the work of more than fourteen years of negotiation, is a comprehensive le- gal document that created an ordered system for the use of ocean space and for the protection of the natu- ral resources of the oceans.. According to customary use of the seas, the area be-...
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418 • Feldspars Global Resources. icut, to grind feldspar for the newly developed pottery industry in the United States.. The largest production of feldspar in the United States is in North Carolina, followed by Virginia, Cali- fornia, Oklahoma, Georgia, Idaho, and South Dakota.. China, Turkey, Italy, and Thailand jointly produce approximately 60 percent of the world’s total feldspar. production of...
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Beginning in the 1960’s, government land manag- ers used controlled burns and unopposed wildfires to clear away underbrush and dead trees in public for- ests. The political as well as economic infeasibility of con- trolling overgrowth may have contributed to South- ern California’s “Station Fire” of 2009, which ravaged roughly two hundred square miles of the Angeles Na- tional Forest...
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http://www.fws.gov/fisheries/fisheries.html. Law of the sea. Flax, also known as linseed, common flax, or Linum usitatissimum in Latin, is native to the region stretch- ing from the eastern Mediterranean to India. Flax was probably first domesticated in the Fertile Crescent and was cultivated extensively in ancient Egypt.. Various parts of the plant have been used to produce a variety of products,...
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However, the use of the term “food chain” dates from 1927, when Charles S. Elton described the implications of the food chain and food web concept in a clear man- ner. Food Chains in Ecosystem Description. Stephen Alfred Forbes, founder of the Illinois Natural History Survey, contended in 1887 that a lake com- prises a system in which no organism...
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Forest regulation is the process of determining the ap- propriate size and age structure of the forest over a large area to ensure the continued production of re- source values in perpetuity. production of the whole range of resources from for- est ecosystems in such a way as to maintain ecosystem structure and function in perpetuity.. Food and Agriculture Organization...
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468 • France Global Resources. In 2007, the value of France’s metal and mining industries was 5.8 percent of the total European value in the cat- egory, behind Germany (17.5 percent) and near the production level of Great Britain.. As of 2009, 500 to 600 million metric tons of coal were estimated to be under French soil. However, because of...
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The inert or noble gases are Group VIIIA of the peri- odic table of the elements. Krypton (Kr), atomic number 36, has six naturally occurring stable isotopes and 86), of which 84 is the most abundant (57.0 percent). Although argon has been found in certain igneous rocks with helium, and all the gases have been found in water from hot...
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Genetic diversity. Genetic diversity includes the inherited traits encoded in the deoxyribonucleic acid (DNA) of all living organ- isms and can be examined on four levels: among spe- cies, among populations, within populations, and within individuals. Populations with higher levels of diversity are better able to adapt to changes in the envi- ronment, are more resistant to the deleterious effects...
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hydration of the gel and subsequent crystallization oc- cur, along with shrinkage and cracking of the geode wall, allowing mineral-bearing waters to percolate into the geode and deposit crystals on the cavity wall.. Geodes are found in many parts of the world. Many highly prized geodes that are filled with beauti- ful crystals and curved-banded colors of agate can be...
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Electrictity: Current and Future Prospects The United States leads the world in electrical gener- ating capacity. Hawaii, with one plant that delivers 25 to 35 megawatts, supply- ing about 20 percent of the island’s electrical needs;. Many of the projects were farther along than that, with some in the facility construction and production drilling stage. As of early 2005, the...
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Other geothermal power plants were built beginning in the late 1950’s in various countries, in- cluding Mexico, Japan, New Zealand, and the former Soviet Union.. Department of the Interior. The American Geological Institute’s Dictionary of Geo- logical Terms defines glaciation as the “alteration of the Earth’s solid surface through erosion and deposition by glacier ice.” As much as 75 percent...
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The spectacular classic placer de- posits found in the Klondike, in the Yukon (Canada), and near Sacramento, California, explain the subse- quent gold bonanzas and migration of prospectors, then settlers, into the American West. By far, most gold is found in placers of sedimentary origin. When fine-grain gold is found in alluvial deposits, “panning for gold” is performed to separate...