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141.
Gold has played an important role in the settlement and economics of the United States. Commercial production from 24 states totaled more than 420 million troy ounces (13,000 metric tons) from 1804 through 1995. There were, no doubt, early undocumented discoveries by Native Americans, but the first records are those from the mid-1600's in the east and from the 1770's in the west. Commercial production began in 1804 in North Carolina and spread among several Appalachian states in the 1820's and 1830's as placer deposits were discovered and exploited. After peaking in the 1830's and 1840's, Appalachian production began to decline as deposits were worked out and as miners moved westward in response to the news of the discoveries in California in 1848. Appalachian production virtually ceased with the Civil War while production from California and adjacent states remained at several millions of ounces per year. As the California Gold Rush waned, new discoveries brought the Rocky Mountain states, South Dakota, and Alaska into prominence. Local, state and total production responded to time of discovery, extent of placers, labor availability, technology, government mandates and, of course, the price of gold. By 1900, the major gold rushes had occurred and most of the major producing districts were defined; however, the fixed price of gold (since 1837) provided a decreasingly attractive incentive for more exploration and exploitation. The rise in the price of gold, during the Depression provided a powerful incentive to increase gold production, but one that was cut short by War Production Board Order L-208 which closed the gold mines in 1942. In the post-war period, the fixed price, combined with the prohibition of American gold ownership, again proved to be a disincentive and gold production dropped. The era of free gold price that began in 1968, followed by the permission for Americans to again own gold, brought new interest in gold with prices rising briefly in 1980 to US$850 per ounce and remaining above US$350 per ounce through 1995. This higher price, combined with the technology for bulk mining and processing of low grade ores, provided incentive for new exploration and exploitation. Consequently, gold production soared above 10 million ounces per year in the early 1990's with 65% coming from Nevada. There has been a general decrease in the grade of gold ores since the early 1900's and significant changes in the methods of recovery. Despite the decreasing grade, the reserves of recoverable gold have more than doubled since the early 1970's.  相似文献   
142.
文章基于中美人口贩运历史和现状,从国家方略、法律法规、工作机构、预警系统和受害者救助与安置回归5方面,比较了两国在打击人口贩运方面的优势和劣势。结果发现,中美人口贩运治理国家方略,均是在“以人为本、协同预防、依法打击、积极救助、妥善安置”的框架下制定的。中国更多的是针对打击国内拐卖妇女、儿童犯罪的全面性,而美国则是重点治理商业性跨国人口贩运。中国治理的特色在于自上而下的管理和自下而上的自治,一旦方略、法律法规形成,能够迅速覆盖全国执行;而美国属于联邦制国家,联邦政府与州政府是合作而非隶属关系,加之三权分立与制衡相结合的政治制度和两党制的政党制度,美国治理人口贩运问题的全国执行度、联动性还需进一步考察。最后,就中国如何应对和治理拐卖人口问题提出几点建议,具体包括:1)加大对《中国反对拐卖人口行动计划(2021—2030)》的实施力度,各地需因地制宜地明确行动措施;完善与国家法的衔接并合理吸收借鉴,持续推进针对打击人口拐卖的专门立法,增强应对能力;2)加强国际合作,重视社会建设和治理跨国、跨地域人口拐卖问题;3)细化反拐工作机构,成立专门工作组,设置专项经费,畅通建议渠道;4)构建并完善“...  相似文献   
143.
Postmaterialist theory suggests that under conditions of continuously expanding economic and personal security, younger generations will be less oriented to acquiring material goods and more committed than their older peers to attaining postmaterial social goals such as increased free self-expression and a healthy natural environment. Using the latest World Values Survey sample for the United States, ordinary least squares (OLS) and logit regressions are employed to test whether youth is a predictor of postmaterialism as theory suggests, and whether postmaterialism positively predicts environmental concern and individual actions in support of the environment. Age is found to be a negative and statistically significant factor in explaining variation in the postmaterialism index, and this index is in turn found to be a statistically significant positive factor in explaining individual environmental concern and activism. A combination of increased economic security and entrance of younger generations into adulthood could well matter for our environmental future.  相似文献   
144.
BOOK REVIEWS     
Books Reviewed in this article: Lob Trees in the Wilderness . Clifford and Isabel Ahlgren . Satellite Microwave Remote Sensing . T. D. Allan , ed. Sunbelt Cities: Politics and Growth Since World War II . Richard M. Bernard and Bradley R. Rice , eds. Legacy of Minneapolis: Preservation Amid Change . John R. Borchert , David Gebhard , David Lanegran , and Judith A. Martin . Bloomington, MN: Preparing a Historic Preservation Ordinance. Richard J. Roddewig . The Mountains of Northeastern Tasmania, A Study of Alpine Geomorphology . Nel Caine . Introductory Cartography . John Campbell . Englewood Cliffs, NJ: Changing Climate . Manual of Remote Sensing, Second Edition . 2 Vols. Robert N. Colwell , ed.-in-chief; David S. Simonett and John E. Estes , vol. eds. Remote Sensing in Meteorology, Oceanography and Hydrology . A. P. Cracknell , ed. Multidimensional Scaling . Mark L. Davison . Environmental Karst . Percy H. Dougherty , ed. The Urban Environment . Ian Douglas . Geomorphology of Europe . Clifford Embleton , ed. An Introduction to South Asia . B. H. Farmer . Great Geological Controversies . A. Hallam . Hazardous Waste Management: In Whose Backyard? Michalann Harthill , ed. Energy for Subsistence . Margaret Haswell . Perspective on Ratzel's Political Geography . James M. Hunter . Economic Deposits and their Tectonic Setting . Charles S. Hutchison . Energy Risk Assessment . Herbert Inhaber . Discovering the Vernacular Landscape . John Brinckerhoff Jackson . Climate and Energy Systems: A Review of Their Interactions . Jill Jäger . Dilemmas in Regional Policy . Antoni Kuklinski and J. G. Lambooy , eds. California Farmland: A History of Large Agricultural Landholdings . Ellen Liebman . The Spatial Organization of New Land Settlement in Latin America . Jacob O. Maos . Dark Continent: Africa as Seen by Americans . Michael McCarthy . Westport, CT: Climatology: An Introduction . John E. Oliver and John J. Hidore . Columbus, OH: The Geography of Warfare . Patrick O'Sullivan and Jesse W. Miller . The Expanding City. Essays in Honour of Professor Jean Gottmann . John Patten , ed. Scotland's Environment During the Last 30,000 Years . Robert J. Price . Integrated Urban Models . S. H. Putman . Development and the Environmental Crisis: Red or Green Alternatives? Michael Redclift .  相似文献   
145.
This article examines the extant and potential impact of U.S. antiterrorism policies on Canada‐U.S. cross‐border commerce. Particular attention is focused on the cross‐border trade that takes place between southern Ontario (Canada) and western New York (United States). Evidence from a survey of Canadian and U.S. exporters suggests that U.S. antiterrorism measures have inflated the business costs of exporters on both sides of the border. These measures have also created shipment delays that ultimately imply lost revenues for producers, as well as higher prices for consumers. Security‐related initiatives motivated by a genuine concern for the well‐being of U.S. citizens may nevertheless act as nontariff barriers to bilateral trade. We argue that a potential long‐run consequence of these additional costs is trade diversion. The article concludes with a brief discussion of the implications of the empirical findings for the geography of Canada‐U.S. bilateral trade.  相似文献   
146.
Almost half a century has passed since Jean Gottmann coined the term “Megalopolis” in reference to the almost continuously urbanized stretch of land spanning the East Coast of the United States from southern New Hampshire to northern Virginia. Because a disproportionate concentration of population resided in this Megalopolis, the northeastern core enjoyed an economic and cultural supremacy, and he termed the Megalopolis “The Main Street of the Nation.” By the later 1960s and 1970s, however, population migration patterns began to reflect the influence exerted by the emergence of a second national core centered on the large metropolitan areas along the Pacific Coast, especially those of the Los Angeles and Bay Area conurbations in California. Although of different character, this burgeoning concentration of population, economic activity, and cultural influence may reflect the development of a West Coast Megalopolis that could soon rival the original Megalopolis of the Northeastern Corridor. Today, the U.S. population distribution is largely a bicoastal one. This article documents the emergence of this bicoastal population distribution. Using historical census data and GIS technology, we present a number of novel ways to graphically portray and examine this population redistribution phenomenon. The United States is not unique in witnessing an increasing share of its inhabitants clustering in coastal zones. Current critical policy concerns about the worldwide vulnerability of coastal populations have focused the need for better coastal population estimates and better mapping methods for portraying population redistribution trends.  相似文献   
147.
ABSTRACT. Levels of alcohol consumption are a major public health issue. This study aims to gain a better understanding of how geographical patterns of religious affiliation in the United States relate to geographical patterns of alcohol consumption. We explored state‐level correlations between alcohol consumption and religious adherence. Although we found no statistically significant correlation between overall religious adherence rates and current or binge drinking rates, states with higher adherence rates were significantly more likely to have high proportions of binge drinking among current drinkers. Yet, regionally, we found a strong inverse correlation in the Southeast and a strong positive correlation in the Midwest and Northeast between adherence rates and current and binge drinking rates. These geographical differences were largely explained after stratifying by major religious denominational groupings. States with high Catholic adherence rates tended to have higher drinking rates, whereas states with high Evangelical Protestant adherence rates tended to have lower drinking rates. These findings suggest that the relationship between religion and alcohol may be denomination‐specific and challenge the lay perception that religious adherence per se is associated with less alcohol consumption and less excessive drinking among those who drink.  相似文献   
148.
ABSTRACT. This article examines how National Geographic Magazine's coverage of the U.S. South contributed to the production of an exalted American national identity. The framework of internal orientalism is employed to explain the role of the South as an internal other in the national discourse and to show how even positive representations of the South are often implicated in this othering. In the pages of National Geographic, the New South's progress is measured by the steps it takes away from the Old South. In highlighting the improvements made within the South, the articles provide subtle hints that the legacy of segregation, intolerance, racism, and poverty continues to haunt the region. The articles set up a spatial distinction that construes these evils as inherently southern problems, which implies that however far the New South moves away from the problematic legacy of the Old South, it will never quite reach the American ideal.  相似文献   
149.
Heavy precipitation is one of the most significant natural hazards in the United States today. Knowledge of the climatography, including the temporal characteristics, of this phenomenon is necessary in order to better plan, design for, and predict this hazard. In this study, cluster analysis is used to simplify and clarify the spatial patterns in the time of day heavy precipitation most frequently occurs. Regions with similar diurnal properties are delineated, and the substantial seasonal fluctuations in the regional patterns are traced. Of particular interest is the expansion during the cool season and contraction during the warm season of the nocturnal precipitation regime in the central United States.  相似文献   
150.
Regional brines that underlie the potable groundwater appear to be responsible for the increase in dissolved solids in the Wadi Al Bih aquifer in the Ras Al Khaimah Emirate, United Arab Emirates. In this karstic carbonate aquifer, groundwater extraction exceeds recharge and the reduced heads can induce transport of underlying brines into the potable water aquifer. Increasing dissolved solids with time threatens the continued use of groundwater for agricultural and domestic uses. The potential of intrusion of seawater, dissolution of minerals, or intrusion of regional brines as a source of these solutes were evaluated based on groundwater samples collected in April and September 1996 from the Wadi Al Bih well field and isotope data from previously collected samples. Hydrogeologic conditions and solute modeling suggest the dominant source of solutes in the Wadi Al Bih aquifer is most likely an underlying regional brine. The pervasive presence of tritium is consistent with recent (since 1960s) recharge in the drainage basin, thus, the solutes and water appear to be from different sources. The chemical and isotopic data are also consistent with enhanced groundwater recharge associated with dams constructed to reduce flooding.
Résumé Dans l’aquifère de Wadi Al Bih, dans l’Emirat de Ras Al Khaimah (Emirats Arabes Unis), les eaux sursalées présentes sous les eaux souterraines potables paraissent responsables de l’augmentation en solides dissous. Dans cet aquifère carbonaté karstique, l’exploitation des eaux souterraines est supérieure à la recharge, et la baisse des niveaux piézométriques peut engendrer une remontée des eau sursalées vers la ressource en eau potable. L’augmentation des solides dissous dans le temps met en danger la pérennité de l’utilisation des eaux souterraines pour l’agriculture et les besoins domestiques. Les potentiels de l’intrusion d’eau de mer, de la dissolution des minéraux et de l’intrusion d’eaux sursalées régionales en tant que sources de ces solutés ont été évalués sur la base d’échantillons prélevés en avril 1996 sur le champ captant de Wadi Al Bih, et de données isotopiques acquises antérieurement. Les conditions hydrogéologiques et les modélisations de solutés suggèrent que la source majeure des solutés la plus vraisemblable est une eau sursalée sous-jacente à l’échelle régionale, dans le cas de l’aquifère de Wadi Al Bih. L’omniprésence du tritium concorde avec une réalimentation récente (depuis les années 1960) sur le bassin versant, c’est pourquoi l’eau et les solutés paraissent provenir de sources différentes. Les données chimiques et isotopiques concordent également avec une réalimentation accrue des eaux souterraines, liée à la construction récente de digues pour réduire les inondations.

Resumen El incremento de sólidos disueltos en el acuífero Wadi Al Bih, en el Emirato Ras Al Khaimah, Emiratos árabes Unidos, parece deberse a la existencia de salmueras regionales, subyacentes a las aguas subterráneas potables. En este acuífero carbonatado kárstico, la extracción de agua subterránea supera la recarga y el descenso de niveles puede provocar el transporte de las salmueras hacia las aguas potables del acuífero. El incremento temporal en sólidos disueltos amenaza el uso continuo de agua subterránea para usos agrícolas y domésticos. Se ha evaluado el potencial de intrusión marina, disolución de minerales o intrusión de salmueras regionales como una fuente de estos solutos, a partir de muestras de agua subterránea recogidas en abril y septiembre de 1996 en el campo de pozos de Wadi Al Bih y de datos isotópicos de muestreos anteriores. Las condiciones hidrogeológicas y el modelo de solutos sugiere que la fuente dominante de solutos en el acuífero Wadi Al Bih son probablemente las salmueras subyacentes. Los datos químicos e isotópicos son también consistentes con un aumento de la recarga de agua subterránea asociado con la construcción de presas para reducir inundaciones.
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