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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.
Andrew Herod 《Transactions (Institute of British Geographers : 1965)》1998,23(2):177-191
Research on labour markets has often focused on the economics of work location. Far less attention has been paid to how labour markets are constructed discursively. In this paper, I analyse how the creation of rival discourses concerning traditions of work were central elements in the efforts of two unions to structure local labour markets, in order to retain work for their members in the face of technological innovation. The struggle between the two unions centred on their abilities to construct rival discourses concerning the historical geography of work in the industry. These formed the basis for judicial interpretations concerning whether the actions of the dockers' union represented a legal work preservation action or an illegal work acquisition measure. Such interpretations shaped the subsequent evolution of work and labour markets in the industry. The ability of economic actors to shape discourse in their favour can be a powerful force in the regulation of local labour markets, and thus in the production of economic landscapes. 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.
Nicolas Badalassi 《Cold War History》2018,18(1):1-17
In the early 1970s, the Conference on Security and Cooperation in Europe (CSCE) was the cornerstone of French foreign policy regarding East-West relations. It was considered by Paris as the best way to maintain dialogue with Moscow as well as an instrument to reach the Gaullist goal of overcoming the European status quo. This double objective explains why the French adopted an ambiguous attitude during the CSCE: even though their goal was to challenge the Brezhnev doctrine and initiate a process to meet the aspirations of peoples under Soviet domination, they knew that this would be a lengthy process. For them, it was necessary to avoid provoking the Soviets by putting forward expressively liberal proposals. The French leaders of the 1970s saw the CSCE as the multilateral prolongation of the Gaullist policy of ‘détente, entente, cooperation’. 相似文献
6.
郑伊凡 《中国历史地理论丛》2018,(1):112-117
北京大学入藏的秦代水陆里程简册中记载秦代有"阳"县存在,关于这一新出现的秦县,前辈学者认为可能是位于今河南省方城县的秦汉"阳城"。然而,从简册中记载的"阳"县下属各乡到其他地区的距离来看,"阳县"不太可能在今方城附近,而更有可能是位于先秦"唐"国故地的"唐"县。其他出土材料所见的"唐"县一般写作"阳",清华简《系年》中还有楚国曾灭"唐(阳)"置县的明确记载。秦代的阳县应该就是继承了楚灭唐国之后所设的阳县。 相似文献
7.
《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
8.
Michiyo Nakane 《Berichte zur Wissenschaftsgeschichte》2019,42(4):338-356
Previous research in the history of physics has led us to believe that Yoshio Nishina (1890–1951) virtually single‐handedly imported quantum physics into Japan. However, there are first‐hand accounts that Yoshikatsu Sugiura (1895–1960) also played an important role. Sugiura made his name in quantum chemistry with his contribution to the Heitler‐London theory of the chemical bond. Yet, historians of physics have paid scant attention to him. This paper brings forward information on Sugiura from his letters, his scientific papers, and his own recollections until ca. 1930. By examining this material, the present paper studies Sugiura's accomplishments in Europe and his contributions to the development of quantum physics in Japan. We conclude that Sugiura was one of the most important physicists when it comes to the arrival of quantum physics in Japan. In addition, we assess why he has been under‐appreciated in the history of physics in Japan. Our historical study on Sugiura suggests that, in addition to the position Nishina and his students rightfully occupy, there still are important unexplored aspects in the history of Japanese quantum physics. 相似文献
9.
《增校清朝进士题名碑录·附引得》进士籍贯刊误述论 总被引:2,自引:0,他引:2
毛晓阳 《中国历史地理论丛》2007,22(1):106-115
文章以列表的方式,论述了《增校清朝进士题名碑录.附引得》中存在的6种进士籍贯刊误现象,即:省际进士籍贯刊载互误、省内进士县际籍贯互误、进士籍贯标注字误、以俗名标注进士籍贯、以府名标注进士籍贯及以府、县二级标注进士籍贯。文章并较细致地探讨了该书出现这些刊误的原因。 相似文献
10.