Có 80+ tài liệu thuộc chủ đề "nghiên cứu môi trường"
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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...
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Greece leads the world in the production of perlite and leads Europe in the production of bauxite and benton- ite. The country has few re- serves of petroleum, and it must import most of its oil and natural gas.. The Country. Greece is a small, mountainous country occupying the southern portion of the Balkan Peninsula in south- eastern Europe. Once...
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Environmental law in the United States;. Greenpeace evolved from activists’ concerns about nuclear testing near Alaska in the late 1960’s. awareness of threats to the Earth’s natural resources and calling for action to protect them.. Friends of the Earth Interna- tional. Groundwater is that portion of the Earth’s subsurface water that is contained within the zone of saturation.. It accounts...
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Although aluminum is the most common metal in the Earth’s surface, 8 percent by weight, it is almost always combined with other elements. Aluminum is difficult to separate from the common ores of alumi- num such as oxides and silicates. The liquid aluminum falls to the bottom of the cell, where it is siphoned off by a vac- uum system....
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Hyping Health Risks: Environmental Hazards in Daily Life and the Science of Epidemiology.. New York: Cambridge University Press, 2007.. New York:. Category: Mineral and other nonliving resources. Helium is also found in the Earth’s atmosphere.. The most important use of helium is as a cryogenic coolant, since it permits cooling to temperatures lower than any other substance. Helium is also...
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Since plants are besieged by a panoply of biological agents that utilize plant tissues as a food source, plant protection from pests is a major concern in the horti- culture industry. Plant protection from microbes, nematodes, and insects generally involves either preventing or restrict- ing pest invasion of the plant, developing plant variet- ies that will resist or at least...
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The increase in the num- ber of commercial greenhouse operations has re- sulted in a tremendous increase in the use of hydro- ponic systems. Greenhouses are utilized in the production of a wide array of bedding plants, flowers, trees, and shrubs for commercial as well as for home and garden use. While these sys- tems are similar in their use...
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The large volume of household waste is becoming an increasing problem for many localities in the United States. Because waste incineration requires high tempera- tures, a possibility exists for the generation of electrical energy as a by-product of the process. In the late 1970’s and early 1980’s, “trash-to-energy” processes appeared to have a promising future in several U.S. Char- lotte,...
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Before Indonesia’s independence after World War II, Royal Dutch Shell dominated oil production in the country, with concessions on the three main islands of Java, Sumatra, and Kalimantan (then Borneo). Initial involvement of other foreign firms (most notably Caltex and Texaco) led to discovery of the Duri and Minas fields in Riau Province in Sumatra just before World War II....
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in the postwar era and added to the demand for petro- leum fuels. These diverse uses of the internal combus- tion engine and its dependability made this design a favorite in the marketplace for more than one cen- tury despite its inefficiency and the fact that it pol- luted the environment.. The demand and consumption of petroleum as a fuel...
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Moreover, the combined burdens of gov- ernment subsidies and price controls in the food sector remain burdensome to Iran’s economy.. Wheat, Iran’s most important crop, is grown mainly in the western and northwestern regions of the coun- try. From 1999 to 2004, wheat imports in the Middle East began to contract, especially in Iran. How- ever, this gain was short-lived...
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RIA is used worldwide in the determina- tion of hormones, drugs, and viruses.. The technique is so specific that con- centrations in the picomolar region can be measured. Pharmacokinetics is the study of the rates of move- ment and biotransformation of a drug and its metabo- lites in the body. Many kinetic parameters, such as a drug’s half-life in the...
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Killing Game: International Law and the African Elephant. Walker’s Mammals of the World. Members of the Izaak Walton League of America pledge to strive for the purity of water, the clarity of air,. and the wise stewardship of the land and its resources.. They seek to understand nature and the value of wild- life, woodlands, and open space.. The IWLA...