人类移动性与健康研究中的时间问题

随着地理信息科学的发展,地理学围绕着社会热点问题不断向其他学科交叉渗透,同时学科的交叉也为地理学研究本身注入了热量。空间一直是地理学研究中的基本问题,而时间与空间密不可分,从时间维度研究人类移动性及其丰富内涵具有重要意义。本文在总结人类移动性热点问题的基础上,重点从时间维度探讨了可达性、出行体验与幸福感、人类健康与疾病等问题的研究内容和方法,并从低收入者社区医疗保健可达性研究和阿帕拉契亚乡村地区吸烟者影响因素研究等案例进行详细阐释,最后对人类移动性与健康研究的发展方向进行了展望。     

Effects of grain size on quartz ESR dating of Ti–Li center in fluvial and lacustrine sediments

The electron spin resonance (ESR) dating method has been introduced into the Quaternary chronology for nearly 40 years and has been successfully used for dating of fluvial and lacustrine sediments. In order to evaluate the possible effect of the sediment grain size on the dating estimate, the parallel ESR dating testing was carried out on quartz grains of five different size fractions ranging from 50 to 450 μm extracted from the same fluvial and lacustrine sediment collected close to the M/B boundary at the Donggutuo section, Nihewan Basin, China. The results show that equivalent doses and associated ages vary significantly. However the beta irradiation dose rate of the grains with different sizes accounts for only about 6% of the total deviation of the dating results. At the same time, the sensitivity of quartz Ti–Li center was calculated based on the additional irradiation. It shows that the larger grains are more sensitive than the smaller ones, which can leads to higher saturate ESR intensity and less equivalent dose. The variations of the sensitivity of quartz Ti–Li center of the grains with different sizes are responsible for the primary deviation of the dating results. The results also suggest that 100–150 μm grain size fraction would be priority size for the ESR dating of quartz Ti–Li center on fluvial and lacustrine sediments.     

基于社会网络分析的长三角地区人口迁移及演化

在当今全球化与地方化、区域化的背景下,物质和能量在各节点间的高速流动促进了城市网络的形成并成为一种新的区域组织模式和空间结构,尤其是对区域一体化高度发达的区域产生了深刻影响。以长江三角洲地区为例,从人口迁移的网络空间入手,从网络密度、中心势等角度对1982-2010年长三角地区人口网络的演变进行研究。结果表明：整体上人口迁移网络日趋成熟,但空间分布不均衡;人口迁移主要流向上海、杭州、南京、宁波和苏锡常等核心城市,同时这些城市的人口外迁现象逐渐显现;以无锡、苏州、杭州之间人口迁移联系为主体的省际间人口流动行为增多,空间上具有等级扩散的特征;不同空间尺度的网络结构相互嵌套,在地方尺度下形成了江苏以邻域渗透为主和浙江的等级辐合两种网络结构。最后从就业机会、收入水平、产业结构、迁移成本等方面分析了人口迁移网络的演化历经均质离散-单核心集聚-多核心等级网络-链式空间网络四个阶段的成因。     

酒吧与旅游古镇地方性的建构——以湖南凤凰古城为例

随着全球流动的迅速加快,移动性理论成为解释全球化与地方化冲突的一个有用视角。在第三世界不断蔓延的酒吧消费空间可以看作是移动性的一个重要表征。然而游客带来了旅游目的地变迁,以及西方游客在第三世界国家创立文化飞地的移动性研究结论却无法解释酒吧在中国的古镇不仅成为重要的休闲场所,而且成为了古镇文化的重要组成部分的现象。文章以湖南凤凰古镇为例,运用观察、访谈等定性研究方法探讨酒吧是如何与古镇的地方性相结合的。得出结论如下：1）酒吧起初完全是由游客生产,游客消费的空间是游客在古镇中创造出来的文化飞地;2）由于游客的某些文化行为（绘画、音乐、阅读等）使得古镇叠加了现代文化的地方性,从而与同是现代文化的酒吧相得益彰;3）随着大众游客、组团游客的不断增多,原来的游客关注凤凰古城展现传统文化的习惯已经被打破,组团游客更多地只是对古城匆匆一瞥,更关心的是听觉、嗅觉等身体感觉以及喝醉的放纵感;4）由于漫步的停步与放纵同时汇聚于酒吧,使得游客透过酒吧更好地将身体安放在古镇中,这使得酒吧融入进了古镇中的地方性。综上所述,人与地方的连接是复杂的过程,带有文化与身体2种属性,因为有身体属性的存在,游客对于旅游目的地并不仅仅是审美需求,而酒吧则是在双重属性下连接人与古镇的重要中介。     

LixNiO2—锂电池阴极材料

高温固相反应法在Li—Ni—O体系中成功地合成了具有层状结构的Li_xNiO_2,固溶体区间为0.45≤x≤0.98;用XRD,XPS等技术研究了它们的结构和金属离子Ni的存在价态,用恒电流间断滴定法测得了Li~+在Li_xNiO_2中的化学扩散系数和离子电导率,室温下(?)_i和σ_i分别为10~(-9)cm~2/s和10~(-5)S/cm量级,试验电池充放电实验表明,Li_xNiO_2是有前途的锂电池阴极材料。     

广西来宾铁桥二叠系剖面生物地球化学信号的解读

二叠纪被认为是全球生物繁盛的重要时期,其大气含氧量、温度等条件和现代地球极为相似,因 此,二叠纪古海洋生物和环境的研究对当代环境和气候变化研究具有重要的启示作用。通过分析广西来宾铁桥 二叠系剖面的275个海相碳酸盐岩样品的地球化学组成,考察Ca,Mg,Al,Ti 及其比值的变化特征,研究它们 的生物和环境意义。结果发现,从栖霞组沉积时期到吴家坪组沉积时期,海水中Mg/Ca值总体上呈单调下降趋 势,表明海底洋中脊扩张,洋中脊热液循环加快,全球海平面上升;Al/Ti值在栖霞组沉积时期到吴家坪组沉积 时期呈现一种起伏式的变化,其中栖霞组沉积中期和茅口组沉积后期表现出与其他时段有显著差异的高值,表 明这两个时期海洋生产力繁盛;在瓜德卢普统-乐平统界线,Al/Ti值低,与玄武岩(Al/Ti 值约为6)相近, 指示火山活动强烈,为火山活动导致生物绝灭说提供了地球化学新证据。     

BOOK REVIEWS

Book reviewed is the article: Small-State Security in the Balkans . Aurel Braun. South American Development: A Geographical Introduction . Rosemary D. F. Bromley and Ray Bromley. Interregional Migration, National Policy and Social Justice . Gordon L. Clark. Marketing Architectural and Engineering Services . Weld Coxe. A Geography of the Third World . J. P. Dickenson, C. G. Clarke, W. T. S. Gould, R. M. Prothero, D. J. Siddle, C. T. Smith, E. M. Thomas-Hope, and A. G. Hodgkiss. Wildlife and Man in Texas: Environmental Change and Conservation . Robin W. Doughty. At the Sea's Edge . William T. Fox. Englewood Cliffs Geography and Ecology . I. P. Gerasimov. Urbanization in Contemporary Latin America. Critical Approaches to the Analysis of Urban Issues . Alan Gilbert in association with Jorge E. Hardoy and Ronaldo Ramírez, eds. The Coming of the Transactional City . Jean Gottmann. College Park Visions of City and Country: Prints and Photographs of Nineteenth-Century France . Bonnie L. Grad and Timothy A. Riggs. Worcester Soviet Geography Today: Physical Geography . N. A. Gvozdetskiy, ed. Adaptive Responses of Native Amazonians . Raymond B. Hames and William T. Vickers, eds. Urban and Regional Industrial Research: The Changing UK Data Base . Michael Healey, ed. Cuando se Acaban los Montes . Stanley Heckadon Moreno. A Panama Forest and Shore: Natural History and Amerindian Culture in Bocas del Toro . Burton L. Gordon. Pacific Grove Mozambique: From Colonialism to Revolution, 1900–1982 . Allen Isaacman and Barbara Isaacman. Soviet Natural Resources in the World Economy . Robert G. Jensen, Theodore Shabad, and Arthur W. Wright, eds. The Changing Geography of the United Kingdom . R. J. Johnston and J. C. Doornkamp, eds. Pluralism and Political Geography—People, Territory and State . Nurit Kliot and Stanley Waterman, eds. Landmarks Preservation and the Property Tax . David Listokin. Irrigation Horticulture in Highland Guatemala: The Tablón System of Panajachel . Kent Mathewson. Her Space, Her Place: A Geography of Women . Mary Ellen Mazey and David R. Lee. Man, A Geomorphological Agent . Dov Nir. Dordrecht The Book of America: Inside the 50 States Today . Neal R. Peirce and Jerry Hagstrom. Rivers . Geoffrey E. Petts. Proceedings, United States/Australia Workshop on Design and Implementation of Computer-Based Geographic Information Systems . Donna Peuquet and John O'Callaghan, eds. Outdoor Recreational and Resource Management . John Pigram. Remaking the City: Social Science Perspectives on Urban Design . John S. Pipkin, Mark La Gory and Judith R. Blau, eds. The Crust of Our Earth: An Armchair Traveler's Guide to the New Geology . Chet Raymo. Englewood Cliffs Concepts and Themes in the Regional Geography of Canada J. Lewis Robinson. Vancouver Secondary Cities in Developing Countries: Policies for Diffusing Urbanization . Dennis A. Rondinelli. Beverly Hills Legal Foundations of Environmental Planning , Vol 1. J. G. Rose. Can We Delay a Greenhouse Warming? Stephen Seidel and Dale Keyes. Mobilizing Human Resources in the Arab World . R. Paul Shaw. Prairie Mosaic: An Ethnic Atlas of Rural North Dakota . William C. Sherman. The Future of Conflict in the 1980s . William J. Taylor, Jr. and Steven A. Maaranen, eds. The Visual Display of Quantitative Information . Edward R. Tufte. U.S. 40 Today: Thirty Years of landscape Change in America . Thomas R. Vale and Geraldine R. Vale. Madison Silent Violence: Food, Famine and Peasantry in Northern Nigeria . Michael Watts. Readings in Historic Preservation: Why? What? How? Norman Williams Jr., Edmund Kellogg and Frank Gilbert, eds.     

Chemical Weathering Rates, Erosion Rates and Mobility of Major and Trace Elements in a Boreal Granitic Till

Chemical weathering rates and erosionrates of granitic till in northern Sweden have beenestimated. The present-day chemical weathering rate iscompared with the long-term average weathering ratesince the last deglaciation approximately 8,700 yearsago. Also, the present-day release rates of major andtrace elements due to chemical weathering are comparedwith the mobility of these elements in a spodosolprofile as shown by soil water samples from the vadozezone. The estimation of the past weathering rate isbased on elemental depletion trends in a soil profile(typic haplocryod), whereas the present weatheringrate is based on elemental input/output budgets in asmall catchment (9.4 km²). The long-term averagechemical erosion rate, expressed as the sum of majorelement oxides (SiO₂, Al₂O₃, CaO,Fe₂O₃, K₂O, MgO, MnO, Na₂O,P₂O₅, TiO₂), was estimated to be4.9 gm^-2 yr^-1. The long-term base cation(Ca²⁺, Mg²⁺, Na⁺, K⁺) depletionwas 0.325 keq ha^-1 yr^-1. The currentchemical erosion rate was estimated to be2.43.0 g ^-2 yr^-1, which is at least an order ofmagnitude higher than the rate of physical erosion,and the base cation flux due to chemical weathering is0.356–0.553~keq ha^-1 yr^-1. However,0.074 keq ha^-1 yr^-1 of this flux may be related tocation exchange processes induced by atmospheric inputof acid rain. There is no evidence for any recentlyincreased weathering rate of silicates in this area.The inputs of Cd, Cu, Ni and Zn exceed the outputs,and hence, these elements are currently accumulatingin the soil.There is a distinct seasonal variation in thechemical composition of the soil water. Results fromthe soil water samples show that Na, followed by Siand S (Cl was not measured), are the most mobileelements in the spodosol profile between the E-horizonand the C-horizon, and that Al and Fe were the leastmobile elements. However, there is no simplerelationship between the mobility of an element in thespodosol profile and the current release rate due toweathering of that element. This fact may haveimplications for the validity of the comparisonbetween the past and present weathering rates asperformed in this study.     

Formation and composition of cemented layers in low-sulphide mine tailings, Laver, northern Sweden

Cemented layers (hardpans) are common in carbonate or sulphide-rich mine tailings and where pyrrhotite is the predominating Fe-sulphide. Laver, northern Sweden, is an abandoned Cu-mine where the tailings have low pyrrhotite content, almost no pyrite and no carbonates. Two cemented layers at different locations in the Laver tailings impoundment were investigated, with the aim to determine their effects on metal mobility. The cementing agents were mainly jarosite and Fe-oxyhydroxides in the layer formed where the tailings have a barren surface, whereas only Fe-oxyhydroxides were identified below grass-covered tailings surface. Arsenic was enriched in both layers which also exhibit high concentrations of Mo, V, Hg and Pb compared to unoxidised tailings. Sequential extraction indicates that these metals and As were mainly retained with crystalline Fe-oxides, and therefore potentially will be remobilised if the oxic conditions become more reducing, for instance as a result of remediation of the tailings impoundment.An erratum to this article can be found at     

Evidence of women’s empowerment in India: a study of socio-spatial disparities

Various national and international communities have addressed women’s issues and taken various efforts to empower them so as to enhance their social and health status and involve them in developmental activities. The Indian DHS survey (National Family Health Survey, 1998–1999) provides an opportunity to study women’s empowerment in India. The survey collected information on several dimensions of women’s empowerment from 90,303 ever-married women (ages 15–49), from all the states of India. Utilizing these data sets, four indices – household autonomy index, mobility index, attitude towards gender index and attitude towards domestic violence index – are constructed to measure the different dimensions of empowerment. Using these indices, the spatial and socio-economic and cultural disparities that exist within India are analyzed. Finally, an attempt is made to identify some important determinants for women’s empowerment using multiple logistic regression analysis. The results show that at the national level, 43% of the women have high household autonomy; 23% of the women have high freedom to move outside their home; 40% of the women have no gender preference attitude; and only 43% of the women defy domestic violence. But there are significant divergences in these indices of women’s empowerment across the different states and socio-economic and cultural settings within India. Women’s educational levels emerged as an important predictor for all the four dimensions of women’s empowerment. Additionally, media exposure and age have emerged as the important predictors for some dimensions of woman’s empowerment. This paper was presented by Prof. Kamla Gupta at the International Geographical Union Conference (IGU), held in Canada, 2002.