Spatial and temporal dynamics of the urban heat island effect in a small Brazilian city

This study examined the spatial and temporal patterns of the canopy layer urban heat islands (UHI_UCL) in a small city in southeastern Brazil using the local climate zone (LCZ) system. We analysed the influence of weather conditions, LCZs characteristics, and local surface relief on the UHI_UCL magnitudes. Mobile traverses were used to measure air temperatures during representative nights of wet and dry seasons. Daily maximum magnitudes were observed in compact classes (LCZs 3 and 7) under ideal weather conditions (dry, clear skies, and calm) and higher anthropogenic heat release (weekdays). Seasonal effects on LCZ thermal differences were negligible. The peripheral landscapes were warmer than the city centre in both seasons. Among the warmer areas in the city, magnitudes in compact LCZs 3 and 7 were consistently higher than in LCZ 6. In general, representative sites of the main ‘built’ LCZs in the study area exhibit similar inter-zone temperature patterns to those reported for cities of different sizes from tropical and midlatitude regions. Thermal contrasts of ΔT_{LCZ 3 − D} in the study area reveal significant evidence that small cities can have as strong heat islands as bigger cities. These findings highlight the importance of the LCZ system to identify the main controlling factors driving such thermal differences and the need to extend the application of this approach in other South American cities to yield systematic data of UHI_UCL for urban planning given the coming challenges of climate change over the region.     

Spatial inequality and dynamics of foreign hypermarket retailers in China

The globalisation of retailing has intensified since the mid‐1990s with the rise of a group of international retailers. Foreign retailers have greatly impacted the Chinese retail market since the opening up of the retail sector in 1992. This study aims to examine spatial inequality and dynamics of foreign hypermarket retailers at different geographic scales in China. Although the relative gaps in foreign hypermarkets among Chinese regions are narrowing, the absolute gaps are widening. Logistic regression models are used to identify locational determinants of foreign retailers Carrefour, Wal‐Mart, and RT‐Mart at the intercity level. Carrefour prefers cities with larger urban district populations, longer time of being open to international retailers, and more foreign investment. While urban district populations are significant to Wal‐Mart and RT‐Mart as well, they favour cities where people have higher annual salaries and aim to achieve internal economies of scale at the provincial level. The three leading foreign retailers also have different first‐city and city size preferences in their provincial expansions.     

Spatial and temporal variation in vulnerability of crop production to drought in southern Alberta

Growing evidence of global climate change has led to global concerns over the vulnerability of agriculture to drought. Located in a semiarid environment, southern Alberta has suffered significant losses of agricultural productivity due to drought hazards in recent decades. Understanding the relationship between crop production and drought conditions is essential for coping with increasingly uncertain climate conditions. This study attempts to quantify the magnitude of crop production vulnerability to drought in southern Alberta. The standard precipitation index is used to measure drought stress in the region. The empirical results provide a detailed picture of the spatial variation in crop production vulnerability to varying drought conditions. Vulnerability maps from this study reveal that pockets in the study area may experience significant productivity loss given the existing level of adaptive capacity. While the irrigation districts have been associated with a lower level of vulnerability than dryland outside the irrigated region, uncertain water supply under varying climatic conditions coupled with increasing water allocation for non‐agricultural uses may increase the vulnerability in these districts.     

State atrophy and the reconfiguration of borderlands in Syria and Iraq: Post-2011 dynamics

Circumstances in the MENA region invite us to redirect our attention to geographic areas that emerged as primary sites of power-contest. This paper looks into emerging trends in the unraveling of bounded sovereign territoriality in borderlands by examining the contest over military, economic, and socio-political spaces in the wake of the devolution of the monopoly of violence and the rise of a multitude of new and old actors to local prominence. Since 2011, borderlands in the MENA region transformed into considerable sites of contested power by a plethora of actors. The paper points out emergent patterns of deterritorialization and reterritorialization of power in its various forms and manifestations in borderlands. The dynamics of ‘place and performance’ in the borderlands of Syria and Iraq showcase the variety of ways borders were instrumentalized under circumstances of state atrophy and their destructive tendencies for borderlands.     

Urbanizing rural waters: Rural-urban water transfers and the reconfiguration of hydrosocial territories in Lima

This article studies how urbanization processes and associated rural-urban water transfers in the Lima region (Peru) create water control hierarchies that align the municipal drinking water company, hydropower plants and rural communities on unequal positions. By scrutinizing the history of water transfers and hydropower development in the Lima region, the paper shows how imaginaries about the superiority of engineering, the need to generate electricity for national development, the backwardness of the ‘land of lagoons’ where water is diverted from, and about wished-for water abundance in Lima, all became manifested in hydraulic megaprojects. More than technical means to supply water to Lima City, these hydraulic grids, supported by legal, institutional and financial governance techniques; produce diverging material, social-symbolic and political effects for rural and urban water users. While the established system means water control and access for hydropower and drinking water companies, it implies dependence and/or exclusion from the benefits for rural communities. More specifically and beyond questions of outright water grabbing, perceived injustices involve the distribution of water-related benefits, loss of autonomy, and the socio-environmental impacts of territorial transformations.     

The historical dynamics of ethnic conflicts: confrontational nationalisms,democracy and the Basques in contemporary Spain*

ABSTRACT. All the historical moments in which the Basque debate reached political protagonism in contemporary Spain coincided with political contexts of institutional democratisation. The debate on patriotism in the Basque Country is connected with a uniform narrative regarding the Basques and their moral distance from the Spanish nation: the ‘Basque problem’. This narrative has fostered a confrontational discourse between Spanish and Basque nationalism. It has also promoted recourse to specific stereotypical images of the Basques, which bind ethnicity to collective identity. Such representations reveal that the invention of the Basque country as a uniform ethnic collective had much more to do with the internal contradictions of Spanish national identity – and later of Basque identity – than with the existence of a secular conflict between Basques and Spaniards. The Basque case shows that every ‘ethnic conflict’ requires adequate contextualisation in order to avoid simplifying its origins and past pathways to make it conform to present uses.     

Discussion on the variation characteristics of water content of Quaternary soil cover on the top of Yungang Grottoes and the problem of water seepage in caves北大核心

为研究云冈石窟顶部土壤覆盖层的含水率变化情况,建设了土壤环境监测网收集云冈石窟土壤含水率实时监测数据,并分析其时空变化特征及影响因素。结果表明,平坦地形条件下云冈石窟顶部第四纪土壤覆盖层含水率时空变化特征明显:年变化具有周期性,垂向上随深度逐层降低(冬季除外)。春、夏季土壤含水率抬升、储水,秋、冬季下降、失水;在春、夏日土壤含水率呈白天上升、夜晚下降趋势,秋、冬日则呈白天下降、夜晚也下降趋势。土壤含水率时刻处于不停的运动变化之中,受温度、大气降水、微地形等众多因素影响,山体边坡浅层土壤可能为侧向饱和流的入渗通道。降雨对土壤含水率的影响深度与实际入渗深度不一致。云冈窟内顶板及岩壁上部、中部含水率主要受降雨渗透窟顶土壤层、沿岩体裂隙通道进入洞窟的渗漏水控制,而岩壁底部含水率更多受窟前不饱带和与地下毛细水的影响。多年的防水实践也证明云冈洞窟渗漏水主要来自于石窟顶部及附近区域。防渗排水始终是云冈洞窟渗漏水治理的主导思路,建议应根据窟顶土壤厚度、地形地貌和遗址分布等分区治理,充分发挥土壤的防渗作用,减少对土壤覆盖层的过度干预。防渗层材料在具有防渗作用的前提下,应具备一定的透气性,满足“洞窟—覆盖层—大气环境”之间的水汽循环。     

云冈石窟顶部土层水盐分布特征研究

可溶盐是石质文物风化的重要原因,其聚集、运移与水密不可分。石窟顶部土层中的盐是云冈石质文物内部盐分的重要来源,因而研究石窟顶部土层中的水盐分布特征对未来减小可溶盐在石质文物内部的聚集具有十分重要的意义。本研究对云冈石窟顶部不同位置、不同深度土层的饱和渗透系数、含水率、孔隙比、可溶盐含量进行了系统的分析测试,并结合取土位置的坡度和植被覆盖率,研究了云冈石窟顶部土层中水盐分布特征。结果表明:植被覆盖率越高,土体含水量越高;坡度越大,土体含水率越低;土体孔隙比与饱和渗透系数呈线性关系。植被覆盖率、坡度及土体的渗透性能是影响石窟顶部土层水盐分布的主要原因。     

Climate change,conflict, and cooperation: Global analysis of the effectiveness of international river treaties in addressing water variability

Climate-driven water variability is a natural phenomenon that is observed across river basins, but one that is predicted to increase due to climate change. Environmental change of this kind may aggravate political tensions, especially in regions which are not equipped with an appropriate institutional apparatus. Increased variability is also likely to challenge regions with existing institutional capacity. We argue that our best attempts to assess the ability of states to deal with variability in the future rest with considering how agreements have fared in the past. In this paper, we explore treaty effectiveness, or treaty resilience, by investigating whether particular water allocation and institutional mechanisms help mitigate inter-country tensions over shared water. We use water-related events from the Basins at Risk events database as a dependent variable to test particular hypotheses regarding the impact of treaty design on conflict and cooperation over time. A broad set of climatic, geographic, political, and economic variables are used as controls. The analysis is conducted for the years 1948–2001 using the country dyad as the level of observation. Findings pertaining to our primary explanatory variables suggest that country dyads governed by treaties with water allocation mechanisms exhibiting both flexibility and specificity evince more cooperative behavior. Country dyads governed by treaties with a larger sum of institutional mechanisms likewise evince a higher level of cooperation, although certain institutional mechanisms appear to be more important than others.     

Spatial and temporal variety of prehistoric human settlement and its influencing factors in the upper Yellow River valley,Qinghai Province,China

We report an investigation of forty-two prehistoric sites in the upper Yellow River valley located in Guide, Jianzha, Hualong, Xunha and Minhe, Qinghai Province, China, including forty-four new radiocarbon dates from twenty-four sites, review published archaeological surveys and radiocarbon dates, analyze landform features and discuss the reasons for spatial and temporal variety of regional prehistoric human settlement. Our results suggest that people occupied the upper Yellow River valley during the early Holocene, but a continuous archaeological record begins only after about 5500 Cal yr BP. Thereafter, the intensity of prehistoric human settlement in the area is varied. Neolithic human settlement spread northwestward to high altitude areas of the upper Yellow River valley during early-mid Majiayao and Qijia periods, but moved southeastward to lower locations in the area during late Majiayao period. During the Bronze period, two coeval archaeological cultures, the Kayue and Xindian, occupied the upper Yellow River Region. Kayue archaeological sites are numerous and widely distributed in the high areas of the upper Yellow River, while Xindian sites are restricted to the lowest basin of the region. Variation in site density and location are likely the result of changing paleoclimate and technology.     

The placing of matter: industrial water pollution and the construction of social order in nineteenth-century France

Set within a Douglasian framework, this paper explores the genesis and the social significance of the concept of environmental ‘pollution’ in late nineteenth-century France by drawing on printed scientific and medical sources and analysing archival material from administrations and industrial companies. ‘Pollution’ brought together various strands of water research (especially water analysis, bacteriology and hydrology) but also served as the foundation of a discourse on industrial responsibility. It was a response to the new material circulations created by industrial discharges in river. Paradoxically, it condoned industrial discharges in watercourses, which the hygienist community deemed less dangerous than domestic wastewaters. The co-production of pollution science and nineteenth-century industrial order explains why industrial water pollution was allowed to go unabated. The incapacity of the legal framework of the time to accommodate polluting discharges as legal objects and find legitimate places for them, the power politics at work around pollution and scientific controversies themselves made discharges very difficult to challenge in court. Accordingly, water pollution was regulated informally and industrialists were able to claim rivers as legitimate places for industrial matter against challenges brought up by other social actors.     

基于电阻率成像法的莫高108窟墙体内水盐运移过程分析

非均质的砂砾石层是莫高窟壁画的主要墙体,但砂砾石层的非均质性如何在水盐运移过程中发挥作用却还不清楚。为此,通过在108窟西壁面上1 m×1 m和2 m×2 m范围的三维高密度电阻率成像监测,发现在这些区域上,墙体电阻率的空间分布都是非均匀的,低阻值区域在空间位置、大小和形状上都会随时间而变化。这明确说明在构成墙体的非均质砂砾石层内存在着重要的水分饱和与非饱和过程(再分配过程),正是这一不断重复的饱和与非饱和过程促进了墙体内水分的运移和盐分在一些特定区域的聚集。研究成果对全面认识莫高窟墙体内的水盐运移机理,减轻和防治壁画盐害都具有重要意义。     

The cultural construction of Italy in Albania and vice versa: Migration dynamics,strategies of resistance and politics of mutual self-definition across colonialism and post-colonialism

This article analyses the shifting ways in which Italy has been strategically represented in Albania during the different key passages of the latter's relatively recent history as a sovereign independent state. As a parallel narrative, the article also examines the way Albania has been equally strategically represented in Italy before and during the two periods in which Italy has been militarily involved in Albania, and the way this has been consistent with an attempt to elaborate and sustain a politically strategic definition of Italian identity and culture. The history of the asymmetrical relationship between Albania and Italy is deeply embedded in the social, cultural and political environments that are on the two shores of the Adriatic Sea. The cultural construction of Albania in Italy and vice versa of Italy in Albania should be linked to seemingly independent instances of domestic reforms. The dynamics of projective identification or dis-identification stemming from these instances should be seen as intertwined within two parallel processes of mutual definition encompassing both the colonial and the postcolonial relations between and within the two countries.     

Experimental examination of animal trampling effects on artifact movement in dry and water saturated substrates: a test case from South India

This paper presents the motivation, procedures, and results of an experiment that examines short episodes of animal trampling in dry and water saturated substrates in South India. While horizontal artifact displacement was similar to that modeled by other trampling experiments, vertical artifact displacement in water saturated substrates was greater than any reported experiment to date. The toolstone used in this experiment, a silicious limestone, exhibited minimal damage after trampling. Artifact inclination patterning appeared to be a potentially diagnostic middle-range marker of trampling in water saturated substrates. Given the abundant number of Paleolithic sites that are located on flat, open surfaces near water-bodies, or experience monsoonal climatic regimes, we propose that future excavations should measure artifact inclination on a regular basis.     

Spatial variations in the salinity of pore waters in northern deep water Gulf of Mexico sediments: implications for pathways and mechanisms of solute transport

Spatial variations in the salinity of pore waters in sedimentary basins can provide important insight into basin-scale hydrogeologic processes. Although there have been numerous studies of brine seeps in the deep water Gulf of Mexico, much less is known about porewater salinities in the vast areas between seeps. A study has been made of spatial variation in pore water salinities in sediments in an approximately 500 km by 200 km area of the northern deep water (water depth >500 m) Gulf of Mexico sedimentary basin (GOM) to provide insight into pathways and mechanisms of solute transport in this portion of the basin. A second objective was to document salinities in the upper 500 m of the sedimentary section, the approximate depth to which methane hydrates, a potential future energy resource, may be stable. Elevated salinities would reduce the P – T stability range of hydrates. Salinities were calculated from borehole logs using a dual electrical conductivity model. Even though much of the northern GOM is underlain by allochthonous salt most of the undisturbed shallow sedimentary section has not been permeated by hypersaline waters. These waters are limited to areas near brine seeps. Hypersaline waters having salinities in excess of 100 g l⁻¹ become more common at subseafloor depths of 2 km and greater. A field study at Green Canyon 65 and published numerical simulations of fluid flow above tabular salt bodies suggest that brines produced by salt dissolution migrate laterally and pond above salt and/or within minibasins and that the dominant mechanism of vertical solute transport is a combination of compaction-driven advection and diffusion, not large-scale thermohaline overturn. Superimposed on this diffuse upward flux of dissolved salt is the more focused and localized expulsion of saline fluids up faults.