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1.
An archaeology of fear and environmental change in Philadelphia   总被引:1,自引:0,他引:1  
Alec Brownlow 《Geoforum》2006,37(2):227-245
This paper examines how mechanisms of social control function to mediate human-environment relations and processes of environmental change in the city. Using the Fairmount Park System of Philadelphia as a case study, I argue that a history of social control mechanisms, both formal and informal, maintained viable socio-environmental urban relationships. Their decline over the last several decades has produced a legacy of fear towards the city’s natural environment that has had, and continues to have, profound socio-spatial and ecological implications. I argue that these changes have their origin in a set of racially motivated decisions made during the volatile years of the late 1960s and early 1970s and that African American women, in particular, have been impacted disproportionately by their consequences. Fear of crime in the natural environment and suspicion of environmental change have resulted in the exclusion of local women and children from what was, historically, a politically and socially viable public space. In this context, urban ecological change is locally understood as more an issue of social control than one of environmental concern.  相似文献   

2.
Based on back scattered electron images and electron micro-probe analysis results, four alteration layers, including a transition layer, a reticulated ferric oxide layer, a nubby ferric oxide layer and a cellular ferric oxide layer, were identified in the naturally weathering products of pyrite. These layers represent a progressive alteration sequence of pyrite under weathering conditions. The cellular ferric oxide layer correlates with the strongest weathering phase and results from the dissolution of nubby ferric oxide by acidic porewater. Leaching coefficient was introduced to better express the response of element mobility to the degree of pyrite weathering. Its variation shows that the mobility of S, Co and Bi is stronger than As, Cu and Zn. Sulfur in pyrite is oxidized to sulfuric acid and sulfate that are basically released into to porewater, and heavy metals Co and Bi are evidently released by acid dissolution. As, Cu and Zn are enriched in ferric oxide by adsorption and by co-precipitation, but they would re-release to the environment via desorption or dissolution when porewater pH becomes low enough. Consequently, Co, Bi, As, Cu and Zn may pose a substantial impact on water quality. Considering that metal mobility and its concentration in mine waste are two important factors influencing heavy metal pollution at mining-impacted sites, Bi and Co are more important pollutants in this case.  相似文献   

3.
Nick Gill  Paula Bialski 《Geoforum》2011,42(2):241-249
This paper contributes to on-going work that seeks to understand the dynamic nature of immigrant social network formation. We explore three propositions, derived from the literature, that might be expected to characterise the ways in which migrant associational ties evolve during and immediately after arrival in their destination country. Evidence is drawn from 42 interviews conducted between January and December 2008 with predominantly Polish migrants to the UK (28) as well as domestic service providers (14). In agreement with the existing literature on immigrant social network formation we find that weak associational ties between migrants are locally dense and rapidly formed. More surprisingly, we also find that the Poles in our sample from lower socio-economic groups tended to rely heavily upon weak associational ties while higher socio-economic group Poles tended to rely on associations made through their employing institutions. This illustrates the importance of socio-economic status in framing co-ethnic migrant network formation. This is significant because we also find that weak associational ties are not unambiguously beneficial to lower socio-economic group migrants who tend to (have to be) more compromising about, and therefore more compromised by, the social ‘friendships’ that result.  相似文献   

4.
The Marmes Rockshelter archaeological site in southeastern Washington state contains a > 11 kyr stratigraphic record that was excavated in the 1960s but only recently analyzed in detail. We present the results of physical, chemical, and isotopic analyses of archived Marmes sediments from rockshelter, hillslope, and floodplain locations. Multiple lines of evidence including éboulis production, soil chemistry, and δ13C and δ18O signatures in soil organic matter and calcium carbonate suggest that relatively cool, moist conditions 10,600 to 9700 14C yr BP were followed by relatively warm and dry conditions as early as 9000 14C yr BP. Warm and dry conditions extended to the late Holocene, followed by a return to cooler and moister climate. The limited range of δ13C and δ18O values in Marmes paleosols suggests that the magnitude of moisture and temperature shifts was locally buffered in the lower Snake River Canyon but adequate to generate significant changes in sedimentation and soil formation, possibly due to nonlinear geological and pedological processes. These buffered canyon environments were well suited for establishing residential bases associated with foraging and logistical collecting strategies and may have minimized the influence of climate changes in food resource abundance.  相似文献   

5.
To avoid dominant positivist explanations of links between climate change and security, I use alternative, human security approaches to study how climate security is managed in one of Spain’s most endangered coastal ecosystems, the Ebro Delta. I find that increasing the downstream flow of sediments retained in upstream dams is a crucial measure for dealing with climate change threats (sea-level rise) in the Delta. Yet, state policies do not increase sediment flow, but instead implement incremental adaptation at the site of climate impact (coast), which, at times, requires executing small-scale land expropriations. Refraining from improving human security via increasing sediment flow benefits corporate interests upstream. At the same time, expropriation silences mild farmer protest downstream and adds insult to injury by conveying to farmers a sense of blame for their vulnerability to climate change. Meanwhile, using expropriation at the service of incremental adaptation goes against the very rationale of expropriation established by Spanish legislation and creates a fundamental contradiction between what the practice is meant to deliver, namely security and the social contract from the part of the state, and what it actually does, i.e. permit the state to evade providing human security. I conclude that, under climate change, achieving human security, the delivery of the social contract, and corporate rent-seeking at the same time may not be possible. Moreover, rather than the social contract been threatened by state incapacity to respond to the effects of climate change and breached social contract expectations of vulnerable communities, it is the actual mobilisation of the contract in order to respond to climate change that diminishes human security.  相似文献   

6.
This paper examines how people explain reasons and impacts of environmental change in the low-rain savanna of the central Sudan and mountainous forest lands of northern Thailand. The explanations are analyzed by using the concept of environmental literacy, which refers to the people’s ability to grasp the environment and its interactions. The paper aims to study people’s conceptions of the environment, which compose one factor in directing their behavior. For the study, rural inhabitants in the State of North Kordofan, the Sudan, and the Chiang Mai Province in Thailand were interviewed.It was noted that an individual’s capability to understand the environment is alone insufficient to address environmental problems because the efficient alleviation of the problems requires collective actions at all levels, and because of factors beyond an individual’s control. However, the results supported the assumption that the local people have knowledge of their environment that may help in developing sustainable environmental management practices. The main advantages of using the environmental literacy concept are argued to be its dynamic and synthetic essence, its link to sustainable behavior, and wide applicability in various contexts within heterogeneous communities.  相似文献   

7.
We investigate seasonal variations in the diet and drinking water of four Great Lakes mastodon (Mammut americanum) specimens using stable isotope analysis of serially sampled inner-enamel bioapatite structural carbonate (δ13Csc, δ18Osc), and previously published bulk analyses. Isotopic analyses and thin section measurements showed that mastodon tooth enamel extension rates (~ 12–4 mm/yr, decreasing toward the cervix) were lower than those of mammoths or modern elephants. Mastodons had distinct and highly regular seasonal variations in δ13Csc and δ18Osc, which we interpret in the context of local glacial history and vegetation changes. Seasonal variations in δ18O were large but variations in δ13C were small, and may have been obscured if coarser sampling methods than our inner-enamel sampling approach were used. Thus, our approach may be particularly useful for understanding relatively small seasonal changes in δ13C within C3 environments. The seasonal patterns, though not entirely conclusive, suggest that the Ontario mastodons did not migrate over very long distances. Rather, the climate and seasonal dietary patterns of mastodons within the region changed over time, from ~ 12,400 to 10,400 14C yr BP (~ 15,000 – 12,000 cal yr BP). Insights gained using these methods can contribute to a better understanding of megafaunal extinctions and Paleoamerican lifeways.  相似文献   

8.
Rapid land-use change has taken place in many arid and semi-arid regions of China over the last decade as the result of demand for food for its growing population. The Heihe River Basin, a typical inland river basin of temperate arid zone in northwestern China, was investigated to assess land-use change dynamics by the combined use of satellite remote sensing and geographical information systems (GIS), and to explore the interaction between these changes and the environment. Images were classified into six land-use types: cropland, forestland, grassland, water, urban or built-up land, and barren land. The objectives were to assess and analyze landscape change of land use/cover in Heihe River Basin over 15 years from 1987 to 2002. The results show that (1) grassland and barren land increase greatly by 22.3, and 268.2 km2, respectively, but water area decreased rapidly by 247.2 km2 in the upper reaches of Heihe River Basin; (2) cropland and urban or built-up land increased greatly by 174.9, and 64.6 km2, respectively, but grassland decreased rapidly by 210.3 km2 in the middle reaches of Heihe River Basin; and (3) barren land increased largely by 397.4 km2, but grassland degraded seriously and water area decreased obviously by 313.3, and 21.7 km2, respectively in the lower reaches of Heihe River Basin. These results show that significant changes in land-use occur within the whole basin over the study period and cause severe environmental degradation, such as water environmental changes (including surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality), land desertification and salinization, and vegetation degeneracy.  相似文献   

9.
Extensive nebkha areas develop mainly under the control of aeolian processes, and their sediments record information on regional environmental changes during different periods. Such areas have developed on the dry riverbeds and deserted arable lands of China’s Alaxa Plateau, Taklimakan, and Kumutage deserts. In this paper, we studied nebkhas that had developed in the Heicheng–Juyan region to determine their CaCO3 contents, particle size distributions, and creation dates. Extensive human activities have occurred in this region since at least in the late Tang Dynasty (618–907 ad). Although historical records show that most of the region’s rivers dried up around 1372, surface water persisted in some areas until the early Qing Dynasty (1644–1911 ad). After the 1600s, extensive nebkhas began to develop due to drying of the region’s rivers. The early stages of nebkha development were controlled by both the sediment supply and the regional wind regime, whereas late stages were controlled primarily by variations in wind activity. In the Alaxa Plateau, it took about 100 years for arable lands and riverbeds to evolve into gobi deserts, and during this time, several phases occurred with different levels of wind activity. The land degradation processes in this region are mainly controlled by surface water resources, and the impact of human activities such as reclamation on land degradation appear to have been overestimated in previous studies.  相似文献   

10.
Migration is frequently portrayed as a negative force in its relationship with economic and social development. This negative perception is exhibited through describing population movements as either ‘forced’ (e.g. political and environmental refugees) or ‘voluntary’ movements (e.g. economic and uninhibited relocation). This paper examines the limitations of this conceptual dualism. It points out that the dualistic approach, widely used in the context of developing countries, simplifies a highly complex phenomenon by ignoring its essential heterogeneity and spatial and temporal dynamics. As such, it is limited in explaining and understanding the globally diversified, historically and politically contextualised situations. Focusing on the migratory experiences of contemporary Vietnam, the study identifies major patterns and trends of population mobility in the country in the past fifty years. It shows that despite the state’s continued attempts to reshape the spatial distribution of population over recent historical periods, the policy outcomes with respect to population mobility have been swayed as much by individuals and their families in pursuit of their own aspirations and livelihoods as by state plans. The Vietnam case has provided evidence of a much more complicated relationship between migration and livelihoods than the conceptual dichotomy assumes, and the opportunity for a richer set of policy options. We argue that the evidence from Vietnam, and elsewhere, warrants an integrated approach to studying migration, combining analysis at the macro- and micro-levels with the nexus lying at the critical decision-making point of the individual or household.  相似文献   

11.
通过对文献资料的总结、统计分析,结合对我国东北地区的实地考察和初步研究结果,论述了我国东北地区晚更新世中晚期以来环境变化与猛犸象—披毛犀动物群演化、灭绝的研究现状和存在问题及其与国际对相应时段猛犸象研究之间的差距。提出加强对我国东北地区晚更新世气候环境的重建、认识气候变化的区域特点和突变性,系统而可靠地建立以猛犸象—披毛犀为主的化石动物年代序列、区分主要类型化石动物年代是研究的关键。以独立的气候环境变化和化石动物的年代序列为参照系,在区域环境变化的框架内讨论化石动物群生存的气候环境、生态特征和灭绝过程,进而探讨动物群演化及灭绝与气候环境变化的关系。这将为认识区域环境突变、动植物对环境变化的响应、我国东北地区晚更新世猛犸象—披毛犀动物群与欧亚大陆其它地区猛犸象之间的内在联系,认识人类演化与生存环境的适应、动植物演替与绝灭的临界条件等一系列重大科学问题提供资料。  相似文献   

12.
Armed conflict has played an increasingly important role in the transformation of key social and environmental systems at multiple spatial and temporal scales. Accelerated resource flows and environmental change dynamics intersect with conflict processes in ways that are substantial and yet inadequately understood. Drawing on research along the Pakistani border in eastern Afghanistan’s embattled province of Nangarhar, we employ a coupled systems approach for understanding the ways in which social-ecological processes shape and are shaped by armed conflict. Based on field surveys, geospatial analysis of land and forest change, and participatory research among local communities, government agencies and military actors, we identify several causal processes linking conflict and dynamics of social-ecological change in the context of multiscalar geopolitical processes. We focus attention on four inter-related elements: (1) transitional modes of resource governance relating to armed militia groups and state intervention, (2) forest changes related to illegal logging and trade networks, (3) the erosion of upper-montane rangelands through encroachment and changing pastoral responses to conflict, and (4) significant land use changes in the agricultural sector toward the cultivation of opium poppy. Our research highlights the importance of center-periphery relations, the problematic nature of local agency, and the ways in which local social-ecological elements—here, particularly, timber and opium—become political objects within competing narratives of (in)security and ongoing state formation.  相似文献   

13.
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’.  相似文献   

14.
The vegetation of the treeline ecotone of the southern declivity of arid High Asia (Hindu Kush, northern areas of Pakistan; Himalaya, northern central Nepal) is dominated by hedgehog-like open dwarf shrublands of thorny cushions. Since climatically sensitive ecotones are always also sensitive to human impact, the question arises whether the current lack of forests is a result of the Subboreal climate decline or of human impact. Due to inadequate knowledge of the pollen flora and of ecological indicator values of the plants, pollen analyses in High Asia have mainly been limited to the regional verification of globally known climatic impulses. However, the role of human impact on regional vegetation patterns has been widely neglected. We postulate that today's open dwarf shrublands replace woodlands and forests. Isolated vigorous juniper trees and successful reforestation appear to confirm our hypothesis. An abrupt decline of Pinus forests before 5700 and 5400 ka cal yr BP can be demonstrated. As the first indicator pollen of human impact appeared at both sites synchronous with the forest pollen decline, we infer human impact to be a more decisive cause for this environment change superimposing the effects of a climatic deterioration. The forests were displaced by open dwarf shrublands.  相似文献   

15.
山东小清河流域湖泊的环境变迁   总被引:3,自引:3,他引:3       下载免费PDF全文
小清河流域为西起济南,东至渤海湾,南缘泰鲁沂山地北麓,北界黄河之间的区域。在史前及历史时期,小清河流域湖泊广布,在地层沉积记录和古文献记载中均得以证明。这些湖泊形成于早全新世,在中全新世达到鼎盛,晚全新世以来湖泊逐渐衰退与消亡,如原来存在的鹊山湖、浒山湖、清水泊等湖泊,这在古文献中也多有记载,现已在平原上消失。本文着重对麻大湖、锦秋湖、白云湖等的历史演变进行了探讨。通过查阅历史文献、地层剖面分析、地名考证等多种途径和方法对小清河流域的湖泊消失的原因进行了研究和分析。认为在气候变干的大背景下,湖泊消失的原因主要有两个:一是黄河泛滥所造成的小清河流域的泥沙淤积;二是疏浚河道、围湖造田、过渡利用水资源等人类活动的影响。研究本区湖泊的形成与消亡,对恢复古环境、探讨其演变过程有着重要的意义。  相似文献   

16.
Located at the interface of terrestrial and marine ecosystems, mangroves are particularly sensitive to environmental change. They provide a sedimentary sink for organic carbon, whereby cores can provide detailed records of mangrove species. We aimed to trace the history of mangrove development over the past 150 years in Yingluo Bay, SW China. Sedimentation rates (avg. 0.32 and 0.37 cm/year) were calculated on the basis of ln(210Pbex) vs. mass depth, and offset the rate of relative sea level rise (0.22–0.24 cm/year), leading to a seaward expansion of new mangrove habitats. Chemical tracers (δ13Corg and C:N) and an isotope mixing model were utilized to trace the contribution of mangrove-derived organic matter (MOM). Changes in the relative abundance of pollen from mangrove plants was used to compensate for diagenetic alteration of the stable isotope values and potential overlaps in isotope values for different sources of organic matter. The result of Pearson correlation analysis showed that the MOM was moderately positive correlated with total mangrove pollen, indicating that stable carbon isotopes and mangrove pollen provide similar information for tracing mangrove ecosystems. Based on results from this study, compositional changes in mangrove communities could be divided into two main stages: a degradation period (1870–1930 AD) and a flourishing period (1930–2011 AD), corresponding to colder temperature and warmer temperature, respectively. Owing to the location being far away from any industrial area and human activity, temperature may be a key factor for mangrove development.  相似文献   

17.
Focusing on three neighbouring villages in Cambodia, this paper argues the need for a multi-scalar interpretation of the relationship between mobility and wealth. It analyses migrant livelihoods in both sender and receiving areas to show that single scale measurements of mobility are inappropriate in the context of translocal livelihoods because livelihoods enacted across multiple places may possess multiple values of scale and mobility, each co-existing within the same migrant lifeworld. In seeking an improved conception of these complexities, the paper has combined spatial and qualitative analysis of translocal livelihoods to highlight the linkages between mobility in multiple places. On this basis, it posits that the mobility of translocal livelihoods must be assessed at least three scales: the scale appropriate to the sending environment, the scale appropriate to the receiving environment, and the scale on which potential migrations are judged. Making use of this framework allows clear relationships to be observed between mobility and inequality in both the narratives and structures of the communities under investigation.  相似文献   

18.
方修琦 《第四纪研究》2021,41(2):577-588
过去全球变化(PAGES)研究高度关注的热点领域之一是各个时间尺度上的气候变化如何影响人类社会发展,其目的不仅是为了尽最大可能地还历史本真,更重要地是为了揭示具有一般意义的过程与机理并以史为鉴。社会-生态弹性是人类社会的内在属性,可以理解为人类社会忍受各种环境变化、社会、经济与政治动荡冲击的能力,弹性理论能够很好地阐释历史气候变化影响的过程与机制。本文尝试以此为视角,结合中外历史案例,对"历史气候变化如何影响社会发展"问题进行探讨,主要结论如下:1)气候变化对人类社会的影响与社会-生态弹性状态有关,如果气候变化影响仅突破人类社会某一子系统的弹性阈值,整个人类社会仍可通过其他子系统的适应性调整继续维持稳定;2)历史气候变化影响的5种表现形式与社会-生态弹性状态的关系是,人类社会对气候变化敏感但未突破弹性阈值时表现为周期波动或脉冲式变化,适宜性转型或崩溃发生在气候变化影响突破人类社会的弹性阈值的情况下;而迁徙-替代不论气候变化影响是否突破弹性阈值均可发生;3)人类社会可通过适应气候变化过程中的社会学习和创新增强甚至在更高水平上重构社会-生态弹性。  相似文献   

19.
Community economies can be considered as examples of the diverse economies growing outside common capitalist logics of private accumulation and profit, seeking to bypass or reconfigure dominant global trends of societal and economic organization. Yet, these communities seem to fit quite well under a neoliberal program in which responsibilities are shifting downwards, favoring multi-level governance over State intervention and accountability. This binary character makes imperative an open and critical discussion on the development of community initiatives, including on the motivations and visions of citizens practicing alternative ethical consumption. This article explores the neoliberal rationalities embraced by community members within the imaginaries of change they frame and examines how these rationalities contribute to (re)producing neoliberal conditions and forms of governance. Our analysis builds on semi-structured interviews conducted among the members of 11 initiatives in 5 EU countries and on participant observation. We argue here that communities articulate an “alternative imaginary” of change that appears imprinted by core neoliberal rationalities around questions of individual responsibility, the role of the State, and civic participation and equity. It is an imaginary related to the construction of CBEs to by-pass existing socio-political and economic configurations. This imaginary more often than not responds to neoliberal promises of individual freedom and autonomy and seems to undermine CBEs' more radical possibilities at the same time obscuring more diverse voices of transformation.  相似文献   

20.
张建新 《湖南地质》1993,12(3):185-192
湖南省环境问题比较严重。As、Pb、Hg的环境地球化学背景值偏高,Cu偏低。一些地区多种元素过量规模大,地克病、地甲病、肺癌、元素中毒等发病率高。研究表明,地克病与Mo、Ni、V、Cd、As、Hg、Pb、Zn、F、U、P、Cu等的过量分布区相关;饮水型地氟病与非石灰岩区的富F的酸性环境有关。  相似文献   

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