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961.
962.
In 1987, the authors of Our common future argued that unless the world embraced and operationalized sustainable development, it would risk being overwhelmed by a series of interlocking crises related to population growth, urbanization, poverty and environmental degradation. Since then, many authors have argued that the world is on a worst case scenario trajectory. Post‐Rio assessments of progress towards sustainable development have been largely negative. Since 1987, climate change has added a new stressor to the mix while shortening the time frame for transformation. In the context of accelerating change and converging stresses is the concept of sustainable development as compelling today as it was twenty years ago? Is it reasonable to believe there are means by which to reduce poverty and simultaneously protect the environment? This article briefly reviews the global challenges that first stimulated the concept of sustainable development and asks how contemporary processes of global change are affecting both these challenges and this approach to addressing them. While there are some grounds for optimism, several variables are identified that make sustainable development increasingly difficult to design and implement. The article concludes with an evaluation of how these difficulties might be overcome, and why it is essential that we try. 相似文献
963.
ABSTRACT We use disaggregated data on Chilean plants, and the Chilean input–output table to examine the impact of agglomeration spillovers on total factor productivity (TFP). In common with previous studies, we find evidence for intraindustry spillovers, but none for general cross‐industry spillovers. This picture changes when we take vertical industry relations into account. There are important productivity spillovers from plants in upstream industries. Interestingly, a similar effect cannot be found from plants in downstream industries. The number of plants in these sectors has no effect on plant‐level TFP, just as the number of plants in other industries that are neither important upstream suppliers nor downstream customers also has no effect. 相似文献
964.
965.
A. Stewart Fotheringham 《Geographical analysis》2009,41(4):398-403
This article examines the relationship between spatial dependency and spatial heterogeneity, two properties unique to spatial data. The property of spatial dependence has led to a large body of research into spatial autocorrelation and also, largely independently, into geostatistics. The property of spatial heterogeneity has led to a growing awareness of the limitation of global statistics and the value of local statistics and local statistical models. The article concludes with a discussion of how the two properties can be accommodated within the same modelling framework. 相似文献
966.
Tor A. Benjaminsen Faustin P. Maganga Jumanne Moshi Abdallah 《Development and change》2009,40(3):423-445
Farmer–herder conflicts in Africa are often presented as being driven by ‘environmental scarcity’. Political ecologists, however, argue that these conflicts should be analysed within a broader historical and policy context. This article presents a case study of a local conflict in the Kilosa District in Tanzania that tragically culminated in the killing of thirty‐eight farmers on 8 December 2000. To understand the conflict, the authors argue that it is necessary to study the history of villagization and land use in the District, as well as national land tenure and pastoral policies. Attempts at agricultural modernization have fostered an anti‐pastoral environment in Tanzania. The government aim is to confine livestock keeping to ‘pastoral villages’, but these villages lack sufficient pastures and water supplies, leading herders to search for such resources elsewhere. Pastoral access to wetlands is decreasing due to expansion of cultivated areas and the promotion of agriculture. The main tool that pastoralists still possess to counteract this trend is their ability to bribe officials. But corruption further undermines people's trust in authorities and in the willingness of these authorities to prevent conflicts. This leads actors to try to solve problems through other means, notably violence. 相似文献
967.
968.
Christian Meyer Guido Brandt Wolfgang Haak Robert A. Ganslmeier Harald Meller Kurt W. Alt 《Journal of Anthropological Archaeology》2009,28(4):412-423
The Corded Ware is one of the major archaeological traditions of Late Neolithic Europe. Its burial customs are characterized by single graves but multiple burials also occur. We present a detailed study of antemortem and perimortem trauma in a group of Corded Ware skeletons from four multiple graves and give the most probable interpretation of the site, based upon all available bioarchaeological evidence. The pattern of observed injuries in male, female, and subadult skeletons, including cranial trauma, arrow wounds, and fractures of the forearm and hands points towards a violent event that resulted in the death of all individuals, most probably a raid. In contrast to comparable Neolithic raid sites, there was no complete extermination of the local population and no use of mass graves. The burials have been arranged with care and detailed knowledge about biological kinship ties [Haak, W., Brandt, G., de Jong, H.N., Meyer, C., Ganslmeier, R., Heyd, V., Hawkesworth, C., Pike, A.W.G., Meller, H., Alt, K.W., 2008. Ancient DNA, strontium isotopes, and osteological analyses shed light on social and kinship organization of the Later Stone Age. Proceedings of the National Academy of Sciences of the United States of America 105, 18226–18231]. The combination of clear causes of death and the proven biological relationships among some of the individuals, including a nuclear family, provides new and important insights into Corded Ware mortuary customs and the reasons why and how multiple graves have been utilised. 相似文献
969.
Climatic deterioration in the later middle ages was associated with an increasing frequency of marine storm surges affecting the coasts of the southern North Sea. This paper investigates the impact of storm surges upon the lands bordering the Thames estuary and tidal river between the mid-thirteenth and mid-fifteenth centuries. Land use in the coastal and riverine marshes is reviewed, and the means and costs of defence against marine flooding explored. The impact of flooding upon human use of the marshlands, upon the suburbs of medieval London and upon the Thames fisheries are all investigated. Stress is placed upon the complex interaction of economic and environmental factors in determining the response to the threat of marine flooding. 相似文献
970.
The origins of raw glass used to fashion Mycenaean beads were explored using trace elements analyzed by laser ablation ICP-TOFMS. The use of this minimally destructive technique for the in-situ analysis of these beads was ideal given that the material is exceedingly rare and thus too sensitive to make use of traditional micro-sampling (e.g., by scalpel). A wide range of trace elements were measured to compare these Greek glasses to other Late Bronze Age glass coming from Egypt and Mesopotamia. Of the eleven beads analyzed, four blue glasses colored with cobalt and two blue/green glasses colored with copper have trace element compositions consistent with an Egyptian origin of manufacture. The other five of the glasses, all colored with copper, were found to conform to the composition of Mesopotamian glass. These data are the first to demonstrate direct and clear evidence for the trade of raw glass to the Mycenaean states. 相似文献