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661.
Book reviews     
VANCOUVER'S CHINATOWN: racial discourse in Canada 1875–1980 by K. J. Anderson. 16 × 24 cm, 323 pages. McGill‐Queen's University Press, Montreal, 1991. (ISBN 07735 0844 9) $C34.95 (hard).

GEOGRAPHIC INFORMATION SYSTEMS: developments and applications edited by L. Worrall. 15 × 23 cm, 251 pages. Belhaven, London, 1990. (ISBN 1 85293 140 X) £45.00 (hard).

SAVANNA ECOLOGY AND MANAGEMENT: Australian perspectives and intercontinental comparisons edited by P. A. Werner. 22 × 27 cm, xii and 221 pages. Blackwell Scientific, Oxford, 1991. (ISBN 0 632 03199 9) $A89.00 (soft).

GLOBAL CHANGE AND CHALLENGE: geography for the 1990s edited by R. J. Bennett and R. Estall. 14 × 22 cm, xii and 264 pages. Routledge, London, 1991. (ISBN 0 415 00143 9) $A29.95 (soft).

PLAINS OF PROMISE RIVERS OF DESTINY: water management and the development of Queensland 1824–1990 by J. M. Powell. 17 × 24 cm, xvii and 395 pages. Boolarong Publications, Brisbane, 1991. (ISBN 0 7242 4470 0) $A40.00 (hard).

A SHARED HARVEST: The Australian Wheat Industry, 1939–1989 by G. Whitwell and D. Sydenham. 17 × 25 cm, xi and 324 pages. Macmillan, Melbourne, 1991. (ISBN 0 7329 0584 2) $A29.95 (hard).

TAMING THE GREAT SOUTH LAND: a history of the conquest of nature in Australia by W. J. Lines. 16 × 23cm, xx and 337 pages. Allen & Unwin, Sydney, 1991. (ISBN 1 86373 017 6) $A34.95 (hard).

PLAINS OF PROMISE RIVERS OF DESTINY: water management and the development of Queensland 1824–1990 by J. M. Powell. 17 × 24 cm, xvii and 395 pages. Boolarong Publications, Brisbane, 1991. (ISBN 0 7242 4470 0) $A40.00 (hard).

THE HUMANITIES AND THE AUSTRALIAN ENVIRONMENT: Papers from the Australian Academy of the Humanities Symposium edited by D. J. Mulvaney. 24 × 17 cm, xiii and 123 pages. Australian Academy of the Humanities, Canberra, 1991. (ISBN 0 909897 22 0) $A18.50 posted (soft).

GROWTH (Vol. 167, Sage Library of Social Research) by H. Teune. 141 pages. Sage Publications, Newbury Park, CA, 1988. (ISBN 0 8039 3183 2) US$46.00 (hard); (ISBN 0 8039 3190 5) US$22.95 (soft).

BEYOND GROWTH: elements of sustainable development by U.E. Simonis. 151 pages. Edition Sigma Bohn, Berlin, 1990. (ISBN 3 924859 56 6) DM24.80 (soft).

BEYOND BEEF: the rise and fall of the cattle culture by J. Rifkin. 16 × 24 cm, xi and 353 pages. Viking O'Neil, Melbourne, 1992. (ISBN 0 670 84844 1) $35.00 (hard).

A QUESTION OF PLACE: exploring the practice of human geography by R.J. Johnston. 15 × 23 cm, ix and 280 pages. Blackwell, Oxford, 1991. (ISBN 0 631 18207 1) $39.95 (soft).

GEOGRAPHY IN SOCIETY edited by R. Gerber. 21 × 29 cm, 92 pages. Royal Geographical Society of Queensland, Brisbane, [1992]. (ISBN 0 949286 02 8) $8.00 (soft).  相似文献   

662.
This article investigates efforts by a small regional university without a geography department to incorporate geography into its general education curriculum as part of a “quality enhancement” process mandated by its accreditor. Drawing on interviews and surveys of students and faculty, we highlight lessons learned that may be useful for institutions considering similar changes—including the importance of valuing disciplinary expertise, addressing faculty contingency, and engaging with existing research on geographic education and pedagogy. The initiative, while limited in significant ways, also suggests opportunities for advocates of geography to engage with agendas around general education reform and accreditation.  相似文献   
663.
Nearshore bars play a pivotal role in coastal behaviour, helping to protect and restore beach systems particularly in post‐storm conditions. Examination of bar behaviour under various forcing conditions is important to help understand the short‐ to medium‐term evolution of sandy beach systems. This study carried out over a nine‐week period examines, the behaviour of three intertidal bars along a high energy sandy beach system in northwest Ireland using high‐frequency topographic surveys and detailed nearshore hydrodynamic modelling. Results show that, in general, there was onshore migration for all the bars during the study period, despite the variability observed between bars, which was driven mostly by wave dominated processes. Under the prevailing conditions migration rates of up to 1.83 m day?1 and as low as 0.07 m day?1 were observed. During higher wave energy events the migration rates of the bars decelerated in their onshore route, however, under lower wave energy conditions, they quickly accelerated maintaining their shoreward migration direction. Tidal influence appears to be subordinate in these conditions, being restricted to moderating the localized wave energy at low tides and in maintaining runnel configurations providing accommodation space for advancing slip faces. The study highlights the intricate behavioural patterns of intertidal bar behaviour along a high energy sandy coastline and provides new insights into the relative importance of wave and tidal forcing on bar behaviour over a relatively short time period. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
664.
The juvenile component of accretionary orogenic belts has been declining since the Archean. As a result, there is often controversy regarding the contribution of oceanic basalts to Phanerozoic crustal growth, as in the case of the Central Asian Orogenic Belt (CAOB). Here we report on three groups of Late Carboniferous (316–305 Ma) granitoids in the western Junggar region of northern Xinjiang, NW China, which is part of the southwestern CAOB. They consist of adakites and I and A-type granites, and as a whole have the most depleted isotopic compositions (εNd(t) = + 6–+9, (87Sr/86Sr)i = 0.7030–0.7045, and εHf(t) = + 12–+16) among the granitoids of the CAOB. These features are nearly identical to those of pre-Permian ophiolites in northern Xinjiang, and are clearly different from those of Carboniferous basalts in the western Junggar region. These relationships indicate that the granitoids were mainly derived from recycled oceanic crust by melting of subducted oceanic crust (e.g., adakites), and of the middle–lower crust of intra-oceanic arc that mainly consisted of oceanic crust (e.g., I and A-type granites). Based on evidence from the CAOB, we suggest that recycling of oceanic crust has made a significant contribution to continental crustal growth and evolution during the Phanerozoic.  相似文献   
665.
贵州荔波黑洞碎屑沉积物宇宙成因核素26Al/10Be埋藏年龄   总被引:1,自引:0,他引:1  
河流下切在岩溶区形成的多级层状洞穴,记录了地体隆升和地貌演化历史,但由于测年手段的限制,国内在这方面的研究一直进展不大。近年来,运用宇宙成因核素得到洞穴碎屑沉积物埋藏年龄的方法,已成为反演山地区域构造-地貌演化的新途径。本文尝试运用宇宙成因核素26Al/10Be埋藏测年技术,对属于贵州荔波地区4层洞穴系统的黑洞(第二层)碎屑沉积物进行年龄测定,假设样品进洞前无埋藏史,测年结果显示黑洞年龄至少有 1.06±0.23Ma,并且该地区三岔河流域的侵蚀速率为 55.1±2.3m/Ma。这是对该地区洞穴测年的一次新探索,体现出洞穴沉积物宇宙成因核素埋藏测年技术在我国晚新生代地质地貌演化研究方面具有良好的应用前景。  相似文献   
666.
Speleothem from West Virginia, ranging in age from 2000 to 200,000 yr B.P. contains uranium with U234U238 ratios significantly greater than unity. This ratio varies from one speleothem to another, as does average U content. Initial ratios, corrected for age, are remarkably constant for a given speleothem. By contrast, U234U238 ratios in seepage waters vary significantly from month to month at a given drip site, and their average values differ from that of the speleothem which they are depositing. This discrepancy is attributed either to long-term averaging-out of fluctuations, or fractional precipitation on the speleothem of a chemical species of uranium with a more constant ratio. Constancy of initial U234U238 ratios from Th230U234. datable portions of speleothems should permit U234U238-dating of older portions of the same speleothem, back to about 106 yr B.P., with estimated precision of ±5 per cent.  相似文献   
667.
Anomalous changes in permeability are reported in fractures circulated by fluids undersaturated with respect to the mineral host. Under net dissolution and net removal of mineral mass, fractures may alternately gape or seal, depending on the prevailing mechanical and chemical conditions. The influence on transport properties is observed to be large, rapid, and irreversible: Permeabilities may change by two orders of magnitude in a month, and the direction of permeability change may switch spontaneously, for no apparent change in environmental forcing. These behaviors are apparent in continuous circulation experiments conducted on fractures in novaculite and limestone, intermittently imaged by X-ray CT. In novaculite, permeability reduces by two orders of magnitude as silica is net removed from the sample. Surprisingly, these changes can occur at modest temperatures (~80°C) and stresses (~3.5 MPa), where compaction progresses as temperatures are incremented. Isothermal (~20°C) circulation tests in limestone show similar compaction driven by pressure solution. Where circulation remains undersaturated in Ca, the change in permeability spontaneously switches from net reduction to net increase as a wormhole forms. The surprising magnitude and rapidity of these changes are investigated in the context of the competition between stress- and chemistry-mediated effects.  相似文献   
668.
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.  相似文献   
669.
Almost three decades ago, cultural geographer Richard Pillsbury documented the national expansion of NASCAR and what he considered the erosion of major‐league stock car racing as a unique southern tradition. This claim is reassessed in light of recent research, leading us to suggest that the sport is actually “transcultural” in nature. It is influenced simultaneously by tradition and transition, as well as regional and national forces. In revisiting Pillsbury's seminal work, we document major changes and continuities in Winston Cup racing and briefly examine two North Carolina cases that provide contradictory views on the current relationship between the sport and the American South. North Wilkesboro illustrates how the changing geography of track locations can devalue and demoralize places associated with the tradition of southern stock car racing. The greater Charlotte area demonstrates that the South remains an important part of NASCAR, serving as a gathering place and “knowledge community” for drivers, racing teams, and fans from across the country. In addition to advancing research in the geography of sport and popular culture, the article encourages readers to think critically about regional cultures and their relationship to the forces of nationalization.  相似文献   
670.
Analysis of modern Metasequoia leaves revealed the presence of the structural polyester cutin, guaiacyl lignin units and polysaccharides. Analysis of environmentally decayed Metasequoia leaves revealed that guaiacyl lignin units and cellulose were degraded more than vinyl phenol (the last being the primary pyrolysis product of cutin and plant cuticles) suggesting that cutin is more stable than lignin and cellulose during degradation, contrary to some previous studies. This observation is supported by electron microscopy showing changes in the cellular structure and cuticle of modern, decayed and fossil Metasequoia leaves. Metasequoia fossils from the Eocene of Republic (Washington State) showed a significant aliphatic component, but biopolymeric lignin and polysaccharides were not detected. Fossils from the Eocene of Axel Heiberg revealed the presence of lignin and an aliphatic polymer up to C29 with cellulose, and fossils from the Miocene Clarkia deposit (Idaho) revealed lignin and an aliphatic polymer up to C27 without any polysaccharides. Modern Metasequoia needles heated experimentally in confined conditions generated a macromolecular composition with an aliphatic polymer up to C32 and additional phenolic compounds similar to those present in the fossils. Experimental heating of cutin is known to generate an aliphatic polymer with carbon chain length units <C20. Thus, the n-alkyl component with chain length units >C20 in the heated Metasequoia needles is a product of incorporation of longer chain plant waxes, indicated by the odd/even predominance of the >C27 n-alkanes. The resistant nature of cutin compared to lignin and polysaccharides explains the presence of an n-alkyl component (<C20) in fossil leaves even when polysaccharides are absent and lignin has decayed; cutin and its diagenetically altered products contribute significantly to the presence of aliphatic components in terrestrially derived sedimentary organic matter.  相似文献   
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