Exploring the gap of the digital divide

While much of the literature related to the digital divide focuses on either technology penetration in developed countries or the introduction of new technology to the poor and disadvantaged in the developing world, this paper pays attention to the middle-classes in a developing country which is connected to the Internet but under poor conditions. The digital divide is examined by investigating how the uneven distribution of Internet connection influences distance education students’ participation in higher education. Empirically, the paper is informed by a qualitative study of distance education in Indonesia. The main conclusion is that while in more peripheral areas students may not gain much from the use of new technology, the use of this technology may be useful for the further development of such regions. In central areas the new technology seems to contribute to students’ study situations more effectively and the daily environment empowers the students’ study activities, rather than vice versa.     

Towards economic geographies beyond the Nature-Society divide

This article suggests an approach to economic-geographic quantification that is relevant to engaging the socionatural blurring of an Anthropocene. It develops representations of commodities and of economies that draw upon concepts of absolute, relative, and relational space to help move beyond legacies of the Nature-Society divide in economic-geographic thought. To supplement familiar ways of knowing commodities as bounded objects with associated single values (prices), the piece rereads input-output approaches, providing accounts of how commodities enfold relations among socionatural phenomena. It quantifies and maps the activities and flows of the global economy in 2007 in terms of their embodied carbon emissions, labor times, and harvested land areas alongside their monetary values. Comparing the perspectives that result, it identifies empirical and theoretical challenges that a political-industrial ecology could help address.     

Distribution of Devensian glacial erratics and related evidence elucidate complex ice flow changes across a former ice divide: Northern England

The Lune Gorge and the uplands of the southern Shap Fells represent a key area in developing an understanding of the dynamics of the Late Devensian glaciation (Dimlington Stadial) of northern England. Here ice masses emanating from southern Scotland, the Lake District and the Howgill Fells interacted in the area of the upper Lune valley. Glacial landforms are recorded and tills noted. The dispersal pattern of Shap granite (Sg) erratics is mapped as these clasts are an important tracer of regional ice movements and local ice dynamics. This new information is synthesised with existing literature to provide an understanding of ice dynamics in an area of complex ice flow history. In particular, the ice flow interactions over an area of the western Pennines and the southern Shap Fells have been defined.Early Dimlington ice flow in the vicinity of the upper Lune valley was easterly. Later a northerly shift in the position of a regionally significant west–east aligned ice divide led to topographic steering of southerly basal ice flows, resulting in the development of a western ice stream (Mint Sg plume) and an eastern ice stream (Lune Sg plume); both flowing south around the massif of the southern Shap Fells. At that time, southerly flow of basal ice over the highest ridges of the Grayrigg massif in the southern Shap Fells was relatively weak. Whereas the western stream extended into the Lancashire lowlands, the eastern ice stream was impeded in the Lune Gorge by ice emanating from Borrowdale which forced northern ice to the eastern side of the Lune Gorge where it was blocked by western flowing Howgill ice; the latter extending as far as just east of Kendal.During the late Dimlington, the ice masses over the Mint valley and the southern Shap Fells largely thinned and retreated to the north and west, with a surge in northerly ice movement within the upper Lune valley that did not override the western Pennines. Local ice dynamics are well-illustrated in the western margin of the Pennines (Crosby Ravensworth Fell Gaythorne Plain), where the disposition of erratics reflects local late west-to-east weak down-wasting ice flow and the presence of subglacial meltwater drainage channels. However, ice ultimately decayed in situ on Crosby Ravensworth Fell Gaythorne Plain. Similarly, after complex variable easterly and southerly ice flow during the early Dimlington, there was weak northerly ice flow in the later phase over Birkbeck Fells Common before ice thinned and retreated from Grayrigg Forest. An extensive ice stream, fed by ice emanating from an ice dispersal centre in the eastern Lake District, occupied the large trough of Borrowdale that transverses the southern Shap Fells, but its extension and recession dynamics remain enigmatic.“Glacial Theory …, in its application to the transport of blocks across Stainmoor, involves such obvious mechanical absurdities that the author considers it totally unworthy of the attention of the Society.” William Hopkins, 1842     

Flowers in the bathtub: boundary crossings at the public-private divide

Legal spaces are said to be a crucial materialization of law, serving to communicate legal meaning and, in so doing, helping to produce a liberal-legal consciousness. Given its centrality to legal ordering and liberal ideology, the spatial manifestation of the public-private divide, especially when related to property, would appear to be particularly important in this regard. Public and private are assumed to be both mutually exclusive and exhaustive. Drawing upon empirical research conducted in a neighbourhood in Vancouver, Canada, I argue that spatial and legal categories such as public and private may be more fluid than one might suppose. While the public/private divide is clearly powerful, and informs much policy and governmental action, it is not necessarily the case that it has the purchase on everyday life that some scholars have suggested. People may live in more complicated and overlapping worlds when it comes to supposedly determinate categories such as property.     

Fractured space: a geographical reflection on the digital divide

What does it mean to reflect upon space in connection to telecommunications? If we start with a conception of urban space as being fully integrated, including on an equal footing both information and communication technologies (ICT) and mobility techniques, as well as the founding notion of copresence that we find at the heart of all urban organization, we might then be able to examine the notion of the ‘digital divide’ in a new light. This clearly experimental approach is conducted by a research group called ‘Urbatic’, which is composed of geographers who, for the last three years, have been conducting theoretical research whose objective is to take into account two fields of social science: the theory of urbanity and the theory of telecommunication. Surveys conducted in this perspective focus on the analysis of the choices people make between the different means they can use to cope with distances (copresence, mobility and telecommunication) with a view to constructing their own space. The analysis of these choices leads us to propose a new theorized interpretation of the ‘digital divide’.     

A local groundwater divide in a regional system

This paper presents an analytical solution of a groundwater flow problem involving a local drainage system embedded in a regional system. As an extension of the usual complex variable methods it combines the planes of the hodograph and the Zhukovsky function. This combination of basic parameters appears to be useful for problems involving a free water table and horizontal potential lines. The solution may elucidate the relation between local and regional water divides.     

From networks to uses patterns: the digital divide as seen from Africa

This paper gives an account of the work carried out in the AFRICA’NTI research network, which gathered together a hundred, mostly African, researchers. The results were presented at the conference on “the North–South Digital Divide” in 2003 and 2004 (see www.africanti.org). From network to uses patterns, it first questions the way in which the subject is defined. This is a controversial question; should we speak of a “ditch” rather than of “fracture”? This depends on the point of view, but also on the geopolitical situation, and is difficult to measure. The digital divide may be less important than it is usually believed. This paper presents several types of approaches dealing with the opportunities of new technologies for Africa, geographical aspects stressing the diversity of the situations considered, and the importance of a multilevel systemic analysis based on case studies. It is shown that a slow down in the dynamics of equipment has been observed in Africa for both mobile telephony and the Internet. This then raises the question of a risk of regression for the continent, based on the idea that inequalities in access and uses of ICTs matter less than whether these uses improve the living conditions of the poor people concerned.     

岩溶水系统演化中河间地块分水岭消失过程的数值模拟分析

本文通过数值模拟的方法研究了岩溶系统发展演化过程,并对其中分水岭消失现象进行了探讨。岩溶系统发育模拟中,假设裂隙段为光滑平板裂隙,裂隙中的水流处于平流状态,可以应用立方率描述水流在裂隙中的流动规律;碳酸盐岩裂隙的溶蚀过程可以通过溶蚀动力学的经验公式表示,即每个时间步长内,水流都处于稳定流状态。研究结果表明,岩溶系统溶蚀具有差异性,岩溶最为发育的部位位于潜水面附近,而且垂向的裂隙段比水平向的裂隙段发育更为强烈,深部岩溶系统发育缓慢,其裂隙张开度扩展率与潜水面附近的相差8200多倍。差异性溶蚀还造成潜水面附近形成优先水流通道,至分水岭从系统消失时,其强烈的汇水作用使几乎90%的流出量从此优先水流通道排出。分水岭消失时间受河间地块的范围和降雨量的影响,当河间地块的宽度增大至原来的5倍时,分水岭的存在时间几乎延长至原来的10倍,河间地块的范围愈大,分水岭越难以消失;降雨量增加对分水岭消失时间的影响表现出先增加后减小的趋势。     

鄂尔多斯西北缘桌子山地区河流袭夺和分水岭迁移研究

分水岭是水系演化中的动态因素,通过连续或不连续的水系袭夺而发生迁移,从而导致水系重组。传统的对水系演化的研究主要集中单个河流袭夺事件,而新提出的利用分水岭两侧chi（χ）值差异来描述分水岭的动态迁移过程,能够解释大尺度的河流袭夺事件,描述水系的整体演化过程。文章基于12.5 m DEM数据提取了鄂尔多斯西北缘桌子山地区的chi（χ）值揭示其空间分布具有东高西低的特点,反映桌子山的分水岭处于向东迁移过程。综合分析进一步揭示,在桌子山东西两侧的构造升降和降水条件都无明显差异的条件下,岩性抗侵蚀能力差异是控制桌子山分水岭向东迁移的主要因素,当抗侵蚀能力更强的寒武系、奥陶系灰岩位于背斜西翼,而中元古宙长城系（Pt）沉积碎屑岩位于其下部时,背斜西翼的河流具有更强的侵蚀能力,西翼河流可能会穿过背斜核部,从而侧向袭夺东侧的河流。     

Floodplain sediments on the divide between Huang He and Chang Jiang,Gansu Province,NW China

At Lingfeng, (34°17'N, 104°08'E) on the northern slopes of the Qinling Mountains, a stratigraphic survey was made of a 21-m-profile of floodplain sediments on the watershed between the Chang Jiang (Yangtze River) and Huang He (Yellow River) at 2500 m above sea level. The sediments contain <2 m thick layers of peat and detritical plant matter that had been deposited on the floodplain of the Langouhe. If the radiometric dates are reliable, the chronology of the site spans some 80,000 years, covering an accumulation process from the terminal Last Interglacial up to <24 ka BP. The phase >73 ka BP had cool and wet conditions with a coniferous forest vegetation. Between 73 ka and > 40 ka colder and drier conditions were likely. The vegetation changed from aPicea-Pinus forest to aPicea-Abies-Larix forest with a later increase of non-arboreal pollen. Around 40 ka the climate was warm and moist. The accumulation of silt and organic matter as well as the development of a mixed coniferous forest with high rates of thermophilous trees(Quercus, Castanea) characterize the interstadial conditions at this time. Later on, the climate changed to cool and moist conditions, evidenced by silt and peat accumulation and a coniferous forest vegetation up to <24 ka BP. The loess in this area was deposited after 24 ka and erosion by the tributaries of Chang Jiang and Huang He to a depth of at least 40 m created the watershed between the two river systems.     

空间尺度转换与跨尺度信息链接:区域生态水文模拟研究空间尺度转换方法综述

空间尺度转换是近年来区域生态水文研究领域的一个基本研究问题。其需要主要是源于模型的输入数据与所能提供的数据空间尺度不一致以及模型所代表的地表过程空间尺度与所观测的地表过程空间尺度不吻合。综述了目前区域生态水文模拟研究中常用的空间尺度转换研究方法,包括向上尺度转换和向下尺度转换。详细论述了2种向下尺度转换方法: 统计学经验模型和动态模型。前者是通过将GCM大尺度数据与长期的历史观测数据比较从而建立统计学相关模型, 然后利用这个统计学经验模型进行向下的空间尺度转换. 然而动态模型并不直接对GCM数据进行向下尺度的转换,而是对与GCM进行动态耦合的区域气候模型(RCM) 的输出数据进行空间尺度转换. 通常后者所获得的数据精度要比前者高,但是一个主要缺点就是并不是全球所有的研究区域都有对应的RCM。还详细论述了2种向上尺度转换方法: 统计学经验模型和斑块模型。前者是建立一个能代表小尺度信息在大尺度上分布的密度分布概率函数, 然后利用这个函数在所需的大尺度上进行积分而求得大尺度所需的信息。而后者是根据相似性最大化原则将大尺度划分为若干个可操作的小尺度斑块,然后将计算的每个小尺度斑块的信息平均化得到大尺度所需的信息。通常在计算这种斑块化的小尺度信息的时候,对每个小尺度也会采用统计学经验模型来计算代表整个斑块小尺度的信息。建议用斑块模型与统计学经验模型相集合的方法来实现向上的空间尺度转换     

Crossing the racial divide: a spatial-ecological perspective of offenders in the City of Tshwane Metropolitan Municipality, South Africa

Post-apartheid South Africa has been plagued by an increase in crime and a concomitant increase in the number of incarcerated offenders. Researchers have postulated many proximate causes for the insidious increase in crime, including the vast socio-economic inequalities existing in the country, a remnant of apartheid-era policies and post-apartheid migrations. This article focuses on the neglected field of the environmental criminology of offenders. Following a spatial-ecological approach the relationship between various socio-economic variables and offender rates in the City of Tshwane Metropolitan Municipality in South Africa is modelled. The GIS-based methodological procedure includes a crime offender index, correlational analysis and principal components analysis and produced five factors: social status and income, family characteristics, unskilled earner, residential mobility and ageing population. These five factors, accounted for almost 75% of the variance in the offender index. The findings of our research reject race as a determinant of crime, and rather highlight existing and emerging socio-economic inequalities in the globally connected post-industrial city in regions of political instability and economic uncertainty and its relationship with crime and crime prevention.     

Deformation of granitic rocks across the brittle-ductile transition

A microstructural analysis has been carried out on mylonites and mylonitic gneisses of the Eastern Peninsular Ranges Mylonite Zone, which were formed over a range of metamorphic conditions from lower greenschist to amphibolite facies. Composite planar fabrics in the form of C and S planes are found at all metamorphic grades. Fractured feldspars, kinked biotites and ductile deformation of quartz characterize the lower greenschist facies mylonites. At mid-upper greenschist grade orthoclase grains show dynamic recrystallization textures whereas plagioclase exhibits low temperature plasticity with only minor recovery. Biotite ribbons form by progressive rotation and coalescence of kink band segments to produce chevron fold patterns. At epidote-amphibolite grade and above, recovery processes and annealing recrystallization predominate in all minerals. Residual orthoclase porphyroclasts show strain-related myrmekite formation along those sides of the grains that face the instantaneous shortening direction. Myrmekite formation due to replacement reactions cannot explain this geometry. It is proposed that the myrmekites formed due to a combination of exsolution, replacement and strain-enhanced diffusion.     

Short-period surface waves across the Iberian Peninsula area

A large number of records of near earthquakes, for the period 1950–1975, have been revised at Toledo Observatory (I.G.C.), looking for clear trains of surface waves.All records used correspond to the Wiechert, WWSS or HGLP seismometers of this station.Multiple filtering techniques have been applied to the selected seismograms to obtain Love and Rayleigh fundamental mode dispersion curves.As most of the paths are of mixed continental and oceanic structure, the first interpretation has been made considering an average model for each set of similar seismic paths. However, for some regions, the separation of the two structures (pure continental and pure oceanic) has been attempted.     

Getting across information communities

Amazon’s deforestation affects citizens from varying information communities. Experts like scientists or journalists acquire relevant data on-site and publish valuable information on the Web. But different and sometimes conflicting views on reality impede sharing of information across communities, relevant content remains far too often undiscovered. We introduce rule-based semantic annotations as solution to facilitate the discovery and evaluation of geographical information. With the distinction between shared domain and local information source ontologies, the proposed architecture of a semantically supported SDI for the Amazon also takes the plethora of GI formats into account. Creating semantic annotations is challenging, a recommender system for semantic annotations enables even the non-IT experts to participate. The benefits of the proposed techniques are further illustrated by a scenario which spans across information communities of economics, ecology, and ethnology.     

Magnetostratigraphy across the Triassic-Jurassic boundary in the main Karoo Basin

The end-Triassic mass extinction and the transition and explosive diversification of fauna over the Triassic-Jurassic boundary is poorly understood and poorly represented in the rock record of the Southern Hemisphere. This is despite the rich diversity in both body and trace fossils of Triassic-Jurassic age in southern Africa, which is not found in coeval Northern Hemisphere localities. We report here the first palaeomagnetic polarity zonation of the Upper Triassic-Lower Jurassic continental red bed succession (Elliot Formation; Stormberg Group) in southern Africa. The results from 10 partially overlapping sections, with a composite thickness of ~ 280 m, provide a magnetic polarity chronology of the main Karoo Basin in South Africa and Lesotho. Palaeomagnetic analyses reveal that heating samples to between 150 °C and ~ 300 °C removes the secondary, moderately inclined (~ 48°) normal-polarity component of remanent magnetization. This component overlaps with the present-day field and is comparable to the overprint direction expected from Lower Jurassic Karoo dolerite intrusions. In contrast, a likely primary, high unblocking temperature component, of dual polarity, consistently is of steeper inclination (~ 63°). This characteristic remanence passes the reversals test, except where means are based on small sample populations. There are only two resulting polarity zones for the ~ 200 m thick lower Elliot Formation (LEF) with potential for a thin 3rd magnetozone in the uppermost part. The upper Elliot Formation (UEF), in contrast, which was sampled over a thickness of ~ 80 m, has five polarity zones. The failure of the reversal test for the UEF and combined Elliot Formation (LEF + UEF) indicates that the normal polarity samples may be biased by a younger overprint of either the Jurassic normal polarity of the Karoo Large Igneous Province or present day field. The separate poles calculated for the four sites in the LEF and ten sites in the UEF overlap with the Late Triassic and Early to Middle Jurassic Gondwana poles, respectively. The combined Elliot Formation and UEF pole positions are better constrained than the LEF and therefore considered more reliable. Overall the LEF shows considerable overlap with the Late Triassic Apparent Polar Wander Paths (APWP) poles.     

Lithospheric structural contrasts across the Caledonides of northern Britain

Interpretation of both P- and S-wave data from the 1974 LISPB seismic experiment has resulted in a detailed cross-section across the Caledonian orogenic belt of northern Britain. This section provides clear evidence of lateral variations in lithospheric structure, comparable with the gross geological variations. In particular, lithospheric structure is asymmetric across the orogenic belt: however, the axis of this asymmetry seems to vary with depth within the central part of the belt. Thus the identification of a possible lapetus suture remains moot.     

Seasonal variability in heat-related mortality across the United States

This study examines the seasonal variability in the heat mortality relationship across 29 US metropolitan areas from 1975 to 2004 to discern the seasonal cycle of the health risk from anomalously high temperatures (relative to the time of season). Mortality data for the 30-year period are standardized to account for population trends and overall seasonal and interannual variability. On days when a city experienced an “oppressive” air mass, mean anomalous mortality was calculated. Results show that while the greatest overall health impact is found mid-summer in many locations due to the peak frequency of hot weather occurring at this time, the relative increase in acute mortality on oppressive air mass days is actually just as large in spring as it is in summer, and in some cases is larger. Late summer and autumn vulnerability to anomalously warm or hot days is much less significant than spring days in all areas except along the Pacific coast. Results show significant spatial variability, with the most consistent results across the more ‘traditionally’ heat vulnerable areas of the Midwestern and northeastern US, along with the Pacific Coast. Elsewhere, the seasonal cycle of the correlation between anomalously high temperatures and human health is more ambiguous.