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排序方式: 共有350条查询结果,搜索用时 15 毫秒
1.
A problem which has arisen in discussions of an elm-disease explanation for the Neolithic elm decline has been the lack of fossil records of Scolytus scolytus (F.) (elm bark beetle), which is the main carrier of the fungus which causes the present epidemic of Dutch Elm Disease. Now, the discovery of wing cases of two individuals from elm decline deposits at Hampstead Heath, London, proves that the beetle was present in Britain during this episode. The deposits in which it occurs are described, and the various implications for elm disease causing, aiding or at least occurring during this stage of the early Neolithic are discussed. 相似文献
2.
Jamie B Kirkpatrick 《Geographical Research》2023,61(1):127-137
Isolation effects on the distributions of plant species in fragmented forests appear to be weak over tens to hundreds of years and strong over geological eras. The 250 km wide, 6.5 millennia old Bass Strait, and other millennium-scale disjunctions in the range of Eucalyptus regnans forests, were used to determine the effects of intermediate periods of isolation on plant species occurrence and composition. Three of six floristic communities were found on both sides of Bass Strait. The residuals from multiple regression models using climatic variables on the latitude vector were not explained by latitude, indicating negligible isolation effects from Bass Strait. However, there was a lesser compositional effect of disjunctions within land masses than between land masses, suggesting some effect of the larger barrier. No species that commonly occurred with E. regnans and were largely confined to wet forest exhibited absences from any region where the climate and soils were within their range. If areas isolated from each other for millennia can maintain their vascular plant biota, the expenditure of conservation funds on creating corridors to connect large areas separated by anthropogenic landscape modification might require more justification than it is currently afforded. 相似文献
3.
Bettina Stauffer 《政策研究杂志》2023,51(1):33-52
This paper expands on the Narrative Policy Framework (NPF) by adding a theoretical and empirical exploration into macrolevel narratives. Existing NPF research largely neglects macrolevel narratives, which prevents the NPF from developing its full power. The main contributions of this paper are threefold: (1) It provides a definition of macrolevel narratives by conceptualizing them as the “story form” of a policy paradigm. (2) It proposes a model and an empirical approach, which may lay the foundation for a standard macrolevel NPF approach. (3) It contributes to the NPF's aim of connecting the macro and meso level. The paper tests the model in a comparative multi-method design applied to the Swiss child and adult protection policy. The findings show that macrolevel NPF analysis helps understand where mesolevel policy debates come from, namely from an underlying paradigm and its effects on institutions and culture that enable and constrain macrolevel narratives. 相似文献
4.
Taavitsainen Jussi-Pekka Simola Heikki Grönlund Elisabeth 《Journal of World Prehistory》1998,12(2):199-253
We have investigated the environmental history of human occupation and the development of agriculture in the eastern interior Lake District of Finland. The material consists of archaeological data, which is reviewed in topographical and agrogeological context, and pollen analytical evidence of agricultural indices from eight precisely dated (varved) lake sediment sequences. Before the Viking Age, archaeological evidence, consisting of stray finds, dwelling sites, and graves, is very scarce. Iron Age finds are clearly confined to the lowland environs with silty and clayey soils. During the Viking Age, the number of stray finds multiplies and the first cemeteries are established. Comparison between Viking and Crusade Period finds reveals a topographic shift toward higher locations and morainic soils. Most of the cup-stones are located on upland sites—that is, not in connection with known Iron Age sites. These are interpreted as medieval indicators of slash-and-burn farming of the fertile but stony supraaquatic morainic soils. There is pollen analytical evidence of sporadic cultivation in the area from the Bronze Age onward. Afterca. AD 700, the occurrence of cereal pollen grains becomes regular but remains discontinuous at each site until after the turn of the millennium. There is then an exponential rise in the cereal pollen rain, indicating a fully agricultural population. 相似文献
5.
《中华人民共和国非物质文化遗产法》("非遗法")颁布实施以后,我国已就非物质文化遗产(非遗)传承人权利保障相关问题进行地方法制实践。这些地方立法不仅保留了"非遗法"相关规定之精华,同时亦在此基础上进行了创新。这些地方法制的做法不仅具有正当性,还具有诸多亮点和启示。为缓解非遗领域不同位阶法律适用冲突以及平衡、协调非遗传承人权利与义务之间关系,"非遗法"应就非遗传承人权利保障机制等问题进行规定,以最终实现非遗法律体系形式功能与实质功能的统一。 相似文献
6.
Cheng Lei Meng Hui Zhang Shi Qiang Fang 《International Journal of Architectural Heritage》2015,9(8):942-948
Ancient mortars played a crucial role in the construction of historical architectures due to their physical and chemical compatibility with traditional building materials such as stones and bricks. Therefore, the analysis and optimization of the ancient mortar formula are significant in the restoration and preservation of historical sites. In this work, 20 mortar samples selected from five ancient stone pagodas in Zhejiang Province, China, were analyzed. The results showed that mud, lime-soil mortar, lime-sand mortar, and lime-gypsum mortar were used as binders in these pagodas. The Ca(OH)2/aggregate ratio ranging from 0.3 to 2.7 was usually used to prepare lime mortar. Protein and polysaccharide were also found in some samples. 相似文献
7.
义和团运动时期的北方战事,给包括租界在内的上海及江南民众日常经济生活带来巨大恐慌。身处纷乱的惊惧不安和经济萧条的切实威胁,社会各界普遍企望北方战事早日平息,不致蔓延到南方,这种社会心理氛围,是"东南互保"得以产生和推行的重要原因。 相似文献
8.
How do the political institutional features of developing democracies influence how violence occurs? Building on research showing that ‘hybrid democracies’ are more prone to social violence, this article argues that elite competition for power in the context of limited institutional oversight plays an important role in explaining violence. The framework here presents possible mechanisms linking subnational political dynamics and rates of social violence in poorly institutionalised contexts. It highlights how political competition, concentrated political power, and constraints on cooperation can create opportunity structures where violence is incentivised and the rule of law is undermined. This is examined empirically using sub-national homicide data from over 5000 Brazilian municipalities between 1997 and 2010. Findings suggest violence is greater in contexts that are highly competitive – where political actors face credible challenges and have a more tenuous grip on power – and those where power is highly concentrated – where political actors have held power for longer periods or face limited credible challenges. Findings also suggest violence varies depending on whether interactions between state and municipal government are likely to be constrained or cooperative; and are consistent with literatures emphasising the importance of structural explanations of social violence. In light of on-going democratic transitions across the globe, the article highlights the value of understanding links between institutional context, contentious politics and social violence. 相似文献
9.
Sandra Bruku 《Conservation and Management of Archaeological Sites》2015,17(1):67-76
AbstractEngaging communities in the protection of heritage means that the communities living around the heritage sites are involved in the process of identifying issues that affect the conservation of these sites and can propose ways by which they can be addressed. In Ghana, the Elmina Castle project shows close collaboration between the communities living around these slave forts and castles, the legal custodians, and other stakeholders. This case study unpicks the process to show how the existing traditional systems were approached and involved. The result of this participatory collaboration is a strategic document which will be implemented to ensure proper protection of these sites in the wake of development and modernization. 相似文献
10.
Liu Shilong 《中国历史研究》2016,49(3):126-141
ABSTRACTInterdisciplinary literary and historical studies of late Qing vernacular are rare, and the vernacular texts of the Sichuan Railway Protection Movement have been overlooked by academics. This paper focuses on this topic, arguing that the discursive strategies in such texts revolved around the movement's aim of “breaking the agreement and protecting the railway,” and primarily included discourses on constitutionalism, financial interests, patriotism, cultural order, and the late emperor, as well the ideas of “ridding the emperor of evil ministers,” borrowed from traditional Chinese political discourses, and “national subjugation,” within the context of the national crisis. None of these discourses were “anti-Manchu” or “revolutionary,” yet they were able to mobilize the people of Sichuan to devote themselves to the Railway Protection Movement, as well as attracting the “sympathetic understanding” of high-ranking Sichuan officials, such as Wang Renwen 王人文 and Zhao Erfeng 赵尔丰, thus lending discursive power to the railway protection camp in its game of political chess with the Qing court. Meanwhile, the government's weak discursive power was an important factor in the overthrow of the Qing Dynasty by the revolutionary tide triggered by the Sichuan Railway Protection Movement. The discursive strategies in vernacular texts on railway protection (including the particularly strategic discourse on the late emperor) spread, transformed, and were reborn to varying degrees over the course of history. 相似文献