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721.
利用ERA5再分析资料,区域自动站雨量资料以及双偏振雷达基数据,采用区域历史回归方法,对2020年7月4日雷州半岛火箭人工增雨作业进行物理检验和统计检验。结果表明:作业后作业区域云系云冰含量大幅增加,强回波区面积增大,回波顶高度升高,平均回波强度显著增加。选取1971—2000年作业影响区和对比区逐年7月的平均日降水量资料作为历史样本建立回归公式,结合作业当天区域自动站的雨量资料,计算得出日降水量和作业后3 h累积降水量的绝对增雨量分别为11.07 mm和2.32 mm,相对增雨率分别为51.08%和38.73%,均通过了置信水平为α=0.05显著性检验。因此,雷州半岛开展人工增雨作业对缓解气象干旱,满足水库蓄水等有重要意义。  相似文献   
722.
结合辽宁省历史遗留和自然灾害损毁土地调查工作,总结出一套适用于损毁土地调查与建库的工作流程,涵盖从数据准备、外业核查到内业汇总入库全过程,并对损毁土地复垦方向做出了科学、合理的评价,为其他省份开展历史遗留和自然灾害损毁土地调查提供借鉴和指导。  相似文献   
723.
北京大学人文地理学发展与创新   总被引:1,自引:1,他引:0  
北京大学是中国最早开展人文地理学教学、研究和实践的综合性教学科研单位。人文地理学的前身为1955年成立的北京大学地质地理系经济地理专业。60多年来,北京大学人文地理学秉持“教学科研并重,理论服务实践”的宗旨,从以人文地理基础理论研究为主,逐渐向基础研究与应用实践相结合的纵深拓展,形成了文理工交叉融合的创新研究思维和人文地理学科体系,创建了城市与经济地理系、城市与区域规划系和历史地理研究所。经过60多年的不断发展和开拓创新,对城镇化、城镇体系、城市与区域规划、土地利用评价与规划、产业区位与区域产业演化、产业集群与创新网络、住房与房地产经济、风景名胜区与世界遗产、村镇发展规划、城市社会地理、时间地理与行为地理、历史地理、旅游地理研究与规划、计量地理、交通地理和交通规划等各个领域进行了深入系统的理论研究和应用实践探索,取得了一系列在国内外具有显示度和影响力的创新成果,为国家社会经济发展提供了重要的科技支撑,在推动国家经济社会建设与城乡可持续发展方面做出了重大贡献。未来北京大学人文地理将面向国家战略需求和学科发展前沿,继续包容发展,加强多学科间的交流合作,进一步提升为国家战略决策的服务能力和人文地理学科在世界的学术影响力。  相似文献   
724.
The emerging subfield of historical animal geography provides an opportunity to trace the origins and evolutions of how affective logics framing the conservation of an animal species are co-constituted through embodied interaction between humans and nonhumans, revealing the dynamic ways in which charismatic species are imagined into and out of positions of priority within conservation agendas. This article takes an interest in the shifting perception of predatory species in the environmental conservation movement in the United States, looking to the appearance of jaguars (Panthera onca) in the work of prominent U.S. nature writers Theodore Roosevelt, Ernest Thompson Seton, and Aldo Leopold in the early- to mid-twentieth century. These human–jaguar entanglements reveal a period marked by dynamic changes in the ways in which interspecies encounters were constituted in place; a layering on of affective logics that reveal the complicated origins, practices, and potentialities at the outset of the modern conservation movement. The resulting narratives and images of predatory nature were taken up into dynamic assemblages of jaguar-ness, influencing the formation of new logics that framed public perceptions of predatory natures and provoking a reconsideration of long-held attitudes and policies toward these species.  相似文献   
725.
The recent morphological evolution of Macquarie Rivulet delta, Lake Illawarra, New South Wales, has been assessed from historical parish maps from 1834, 1892, 1916 and 1927 along with aerial photographs from 1938 to 2002. These images were digitised, georeferenced and analysed in a GIS framework. The 1834 sketch map could not be georeferenced and it was excluded from the calculation of delta progradation areas. Between 1892 and 1927 morphological changes were minimal, probably because the areas were not resurveyed between these map editions. A significant change in morphology between 1927 and 1938 reflects a change in source material from maps to aerial photographs. The research highlights that great care must be taken when utilising historical data. Major morphological changes observed between 1938 and 2002 included the development of a large crevasse splay in the 1960s to 1970s and the abandonment and infilling of the delta's previously active distributary channels. The research shows that the morphological changes observed on the delta can be related to both natural processes and anthropogenic modifications to the catchment and thus could be used in the development of catchment management plans.  相似文献   
726.
Yunnan has the largest number of ethnic groups in China, and its rich set of multiethnic toponyms (place names) has earned itself a nickname of “museum of toponyms”. The objectives of this study are to (1) construct a Geographic Information Systems (GIS) database of toponyms in Yunnan from a comprehensive toponymical dictionary series of China, and identify their ethnic roots; (2) enhance the mapping of their spatial patterns and detect possible clusters of ethnic toponyms by spatial analysis methods; (3) analyze the association of multiethnic toponyms with geographic factors by statistical methods; and (4) examine the historical evolution of toponyms. The results show that the highest concentrations of Zang–Mian (Tibeto–Burman) toponyms are in the northwestern and the northeastern mountainous areas, and Zhuang–Dong (Kam–Tai) toponyms cluster in the southwest and the southeast lowlands. In comparison to Han (Chinese majority) toponyms, the Zhuang–Dong toponyms also tend to be closer to rivers and in more remote areas (i.e., farther from major transportation routes and major cities). The centrographic method helps reveal the historical trend of gradual expansion of Han settlement in Yunnan as recorded in the time stamp of toponyms. The paper demonstrates the value of GIS-based analytical methods in toponymical studies.  相似文献   
727.
《The Cartographic journal》2013,50(3):218-233
Abstract

This study uses cartometric techniques to reveal cartographic design considerations operative in Frank H. Galbraith’s 1897 railway mail service training maps. Galbraith’s maps make extensive use of humorous cartouches intended to serve as mnemonic devices for learning railway mail service routes. Poisson and quadrat point pattern analyses are performed on all eight maps in the series to determine whether the mimetic symbols are clustered along the railway mail routes or dispersed throughout the mapped spaces to achieve better graphic balance. Evidence overwhelmingly indicates that the placement of the mnemonic symbols was primarily driven by design considerations. The study therefore proves that it is possible to use cartometric techniques to deconstruct the map document to determine the cartographic design principles operative during the map's construction.  相似文献   
728.
以1979,1992,1996年历史航片为例,简单介绍了历史航片扫描及处理的方法,给出实用有效的工作流程,解决了历史航片储存难题,提高了历史影像管理及应用水平。  相似文献   
729.
730.
Historical political ecology provides a powerful framework for understanding nature–society relations in the past. This approach is applied to municipal drinking water governance in early colonial Lima, Peru, with a focus on how power dynamics influenced sociospatial patterns of water access and control. Sixteenth- and seventeenth-century archival sources are analyzed for material aspects of Lima's drinking water pipeline network and for the management strategies employed by the municipal government. Access to water is demonstrated to have shaped, reinforced, and reflected colonial social divisions and to have been linked to the spatial development of the city, including urban–rural relations.  相似文献   
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