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991.
This article explores the relationship between historical memory, urban space, and photography by way of a case study: the place-specific public art of the Guatemalan photographer and human rights activist, Daniel Hernández-Salazar. As one of a growing number of Latin American artists committed to combating the “institutionalized forgetfulness” of human rights violations throughout the hemisphere, Hernández-Salazar deploys geographically-rich photographic installations to help his society remember its difficult past. The installations, known as Street Angel, are like ghosts haunting the graves of the murdered, fortresses of the powerful, bastions of the complicit. By shedding light on these ghostly angels, this article reveals the important role of photography, as a crucial vehicle of memory, in bearing witness to the unimaginable horrors that consumed much of the twentieth century, as well as that technology’s limitations. It also shows how remembrances of those atrocities depend on urban space for their grounding, articulation, and maintenance. Finally, by probing the artistic impulse and political sensibility that created Guatemala City’s angels of memory, it makes the case that, in the combustible political climate of post-war Central America, the work of remembering the past is not an antiquarian exercise: the labor of memory is a fundamental component of building a just society.
Steven HoelscherEmail:
  相似文献   
992.
Placer deposits mark the ultimate stage of mineral separation in clastic sediments by physical processes in an aquatic regime, whereas duricrusts are an example of extreme element separation by chemical processes in continental environments of deposition. In Quaternary sediments in SE Germany such contrasting types of sediments formed on the NE Bavarian Basement which is underlain by metamorphic and pegmatitic rocks reflecting intense primary element differentiation by themselves.  相似文献   
993.
High-precision Pb isotopic measurements on teeth and possible sources in a given area can provide important insights for the lead (Pb) sources and pathways in the human body. Pb isotopic analyses on soils from the area of Sofia, Bulgaria show that Pb is contributed by three end-members represented by two natural sources and leaded gasoline. Sequential leaching experiments reveal that the alumosilicate fraction of the soils is mainly controlled by natural Pb derived from two mountain massifs bordering the city. Around 1/3 to a half of the Pb in the soil leachates, however, can be explained by contamination from leaded gasoline. Contemporary teeth from Sofia residents show very similar Pb isotopic compositions to the soil leachates, also indicating that around 1/3 to a half of the Pb can be explained by derivation from leaded gasoline. The remarkable isotopic similarities between the teeth and the most labile fractions of the local soils suggest that the lead can be derived from the latter. Pb incorporation in the human body via soil-plant–human or soil–plant–animal–human chains is unlikely due to the fact that no significant farming occurs in the city area. The isotopic compositions of the local soil labile fractions can be used as approximation of the bioaccessible lead for humans. Considering all possible scenarios it appears that soil and/or soil-born dust inhalation and/or ingestion is the most probable pathway for incorporation of local soil lead in the local population. The high-precision Pb isotope data presented in this work indicate that apparently the local soil is what plays major role in the human Pb exposure.  相似文献   
994.
湖南省人类活动诱发地质灾害成因及防治对策研究   总被引:1,自引:0,他引:1  
通过对湖南省人类活动诱发地质灾害的现状进行调查,对人类活动诱发地质灾害的特点和规律进行深入研究,分析人类活动诱发地质灾害的方式、类型、机制、分布及危害状况,提出有效的防治对策和措施,为规范人类活动,减少人类活动诱发地质灾害和为地质灾害防治、监督管理以及人类活动规划提供科学依据。  相似文献   
995.
给出分析各向异性非均质稳定随机渗流场问题的三维有限元模型;结合实际工程问题,统计分析长江荆南干堤士性参数的分布特征,通过Kolomogorov-Smirnov统计检验表明,渗透系数呈高斯分布假设可以接受;通过对长江荆南干堤随机渗流场的三维有限元统计模拟的数值分析,研究长江荆南干堤渗流场的各种随机特性,并进一步对随机模拟结果进行统计检验,验证模拟结果的合理性;在实际的分析研究中把上下游水位的随机波动引入三维有限元的随机分析模型,分析上下游水位的变异性对渗流场矢量的随机干扰和边界条件的随机性对随机渗流场分析结果变异性的影响。在此基础上进一步考虑施加诸如垂直截渗墙、下游导渗沟等抗渗措施后,它们作为复杂边界条件的扰动,在与场内土性参数的变异性共同影响下,对渗流场水头势分布的随机干扰特性,并与相应的确定性稳定渗流场问题的结果对比,证实随机渗流场研究的必要性、可行性及实用性。实现了对长江荆南干堤的三维渗流场的较为全面的随机场模拟及特性分析,分析得到的结论通过统计检验并结合实测工程数据对照证明是可靠的,所研制的程序是适用的。  相似文献   
996.
森林生态系统遥感监测技术研究进展   总被引:9,自引:0,他引:9  
森林是陆地生态系统的主体,森林生态系统监测技术是实现森林可持续利用与全球变化研究的重要支撑与信息保障。从4个方面概述了遥感技术在森林生态系统监测中的应用研究进展:森林遥感分类及变化监测、森林植被参数遥感反演、森林蓄积量与生物量遥感估算、森林干扰遥感监测等。结合遥感技术的发展,总结了森林生态系统监测中使用的多源遥感数据和各类模型,提出集成地面调查数据、高分地-空雷达扫描监测技术,以及多源光学遥感建模技术和生态系统过程模型,构建多维度、多尺度、高时间密度的森林生态系统监测平台的研究展望。  相似文献   
997.
张平宇  刘大千  刘世薇 《地理科学》2018,38(7):1012-1022
人文地理学是地理学的重要分支学科,是区域地理研究不可或缺的重要方面。中国科学院东北地理与农业生态研究所(简称东北地理所)人文地理研究一直坚持稳定的学科方向,具有紧密围绕国家战略需求的时代特征,聚焦不同历史时期东北区域发展重大问题,区域研究特色突出。东北地理所建所60 a来在农业和工业发展与布局、城镇化与城市发展、区域可持续发展、区域综合发展规划等方面开展了大量的应用与基础研究,取得了丰硕的科研成果,为东北地区经济社会发展做出了重要贡献。面向未来学科发展趋势和国家战略需求,东北地理所人文地理研究仍要围绕东北老工业基地振兴与可持续发展这条主线,重点研究现代农业与乡村振兴、新型城镇化与城市转型、产业结构调整与优化布局、国土空间规划与区域治理、跨境区域开发与经济合作、资源环境与区域可持续发展等重大问题,探索东北老工业基地人地关系地域系统演变规律,发扬人文地理研究特色,创新理论与方法,加强学科队伍建设,提升为国家经济社会发展服务的能力和水平。  相似文献   
998.
This study investigates the tropical cyclone (TC) activity associated with the two leading modes of interannual variability in synoptic disturbances. Both leading modes are found to be related to a dipole pattern of TC occurrence between the subtropical western North Pacific and the South China Sea. Therefore, in this study we performed composite analyses on TC tracks and landfalls, based on the cases of combined modes, to highlight the differences. The composite results indicate that these cases are characterized by distinct features of TC tracks and landfalls: more TCs tend to take recurving tracks and attack eastern China, Korea and Japan, or more TCs exhibit straight-moving tracks and hit the Philippines, Vietnam and southern China. Further analyses suggest that these distinctions in the TC prevailing tracks and landfalls can be attributed to the differences in large-scale steering flow and TC genesis location.  相似文献   
999.
As the cornerstone of biodiversity conservation, the core value of protected areas (PAs) is to maintain an area’s natural conditions (both day and night) and to restrict human-caused disturbances to biology and the environment. Although the value of PAs has been universally recognized, light pollution within them is worsening as a result of the widespread use of artificial illumination devices. Previous studies have focused on light pollution in PAs and evaluated light radiation using nighttime light imagery. However, given the scale and span of these studies (national scale and over short periods), PA light pollution research should be advanced further. In this paper, we conducted long-term (1992–2018) monitoring and evaluation of light pollution in African PAs using aligned multi-sensor NTL data. The results showed that 1) Africa PAs were impacted by increasingly severe artificial lights during 1992–2018, with all three light indices showing an accelerating increasing trend. 2) The number of light-polluted PAs also rapidly increased, with more than 80% of PAs experiencing aggravated light pollution as of 2018. Different types of PAs had heterogeneous light pollution, which penetrates indiscriminately into all PA regulation levels. 4) Light pollution in African PAs was divided into three types, including outside invasion, internal sources, and mixed pollution. 5) Human activity intensity surrounding the PAs was highly correlated with light pollution within them, with a maximum effect distance of approximately 245 km. This paper provides new approaches for understanding the patterns of light pollution within PAs, and is a valuable reference for future PA planning.  相似文献   
1000.
Different ways of framing the nexus between climate change and migration have been advanced in academic, advocacy and policy circles. Some understand it as a state-security issue, some take a protection (or human security) approach and yet others portray migration as an adaptation or climate risk management strategy. Yet we have little insight into how these different understandings of the ‘problem’ of climate change-related migration are beginning to shape the emergence of global governance in the climate regime. Through a focus on the UNFCCC Task Force on Displacement we argue that these different framings of climate change migration shape how actors understand the appropriate role of the TFD, including the substantive scope of its mandate; its operational priorities; the nature of its outputs and where it should be situated in the institutional architecture. We show that understanding the different framings of the nexus between climate change and migration – and how these framings are contested within the UNFCCC – can help to account for institutional development in this area of climate governance.  相似文献   
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