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71.
大规模持续的示威游行活动会影响一个城市的经济活动。自2019年6月开始,香港地区持续性的示威游行活动对多个行业产生冲击,香港地区经济受到一定程度影响。快速准确地识别出经济活动受影响区域将有助于政府进行准确损失评估和制定有效的经济恢复政策。本文首次提出使用民航客机夜光遥感结合VGI数据识别经济活动受影响区域的方法。首先在民航客机平台上用手机获取了研究区域2019年8月28日的高度重叠的照片,然后基于摄影测量技术对照片进行拼接处理生成夜光遥感影像,再与珞珈一号-01星夜光遥感影像、POI密度图对比初步筛选出受影响区域。最后通过VGI照片数据进行验证,检测出观塘区有2个经济活动下降的区域,并做了定量分析,发现在观塘区有2个区域的DN值相关比例分别下降了9.52%和19.42%。利用本文的方法能快速识别香港经济活动受影响区域,对于研究其他城市的经济变化有着借鉴意义,在城市精准治理方面也有重要的应用价值。 相似文献
72.
Australian cities have seen continued growth in private car travel that has resulted in increasing vehicle energy consumption and greenhouse gas emissions. While much research has shown that vehicle demand is related to urban spatial structure, very little research has investigated the spatial patterns of private vehicle fuel efficiency (VFE) and its association with socio-spatial circumstances in urban areas. This study has combined State-level motor vehicle registration datasets with standard vehicle efficiency measures that permit a comprehensive understanding of spatial variation of VFE in urban areas. A spatial-based technique was applied to explore intra-urban patterns in socio-spatial conditions of private vehicle efficiency in Brisbane and Sydney. In both cities, the VFE of the private vehicle fleet tends to be lower in outer suburbs than in middle and inner suburbs. The analysis further shows that by linking the standard vehicle efficiency measures to the entire urban fleet datasets the VFE outcome showed a moderate relationship to socio-spatial variables in both cities. The built environment and household economic status are more transferable factors that relate to the VFE across different urban contexts. Outcomes from this research are of relevance to policy makers charged with identifying highly oil-vulnerable communities and designing intervention strategies to improve household vehicle efficiency. 相似文献
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74.
张掖市社会经济系统水循环过程研究与水量估算 总被引:1,自引:1,他引:0
采用投入产出分析方法,估算了张掖市各部门产品中的虚拟水含量; 基于对各产品转化和流动的跟踪,系统研究了本地实体水资源与外地流入虚拟水资源在张掖市社会经济系统各环节中的流动与转化过程。结果表明,种植业部门的实体水转化与虚拟水流动构成了张掖市社会经济系统水循环的主体,外地流入的虚拟水量较少,且主要集中于水资源稀疏型产品; 经济生产对种植业产品较低的消耗水平导致了大量虚拟水的流出。认为增强种植业产品在社会经济系统中的循环强度是张掖市降低水资源流失以及提高水资源利用效率的有效手段。 相似文献
75.
长江上游社会经济因子对侵蚀产沙的影响 总被引:1,自引:0,他引:1
In recent years,the role of human activities in changing sediment yield has become more apparent for the construction of hydraulic engineering and water conservation projec-tions in the Upper Yangtze River,but it has not been evaluated at the macro scale.Taking Sichuan Province and Chongqing City as an example,this paper studies the relationship between socio-economic factors and sediment yield in the Upper Yangtze River based on section data in 1989 and 2007.The results show that sediment yield is significantly correlated with population density and cultivated area,in which the former appears to be more closely related to sediment yield.Moreover,in the relation of sediment yield vs.population density,a critical value of population density exists,below which the sediment yield increases with the increase of population density and over which the sediment yield increases with the decrease of population density.The phenomenon essentially reflects the influence of natural factors,such as topography,precipitation and soil property,and some human activities on sediment yield.The region with a higher population density than critical value is located in the east of the study area and is characterized by plains,hills and low mountains,whereas the opposite is located in the west and characterized by middle and high mountains.In the eastern region,more people live on the lands with a low slope where regional soil erosion is slight;therefore,sediment yield is negatively related with population density.In contrast,in the western region,the population tends to aggregate in the areas with abundant soil and water resources which usually lead to a higher intensity of natural erosion,and in turn,high-intensity agricultural practices in these areas may further strengthen local soil erosion.It is also found that popu-lation tends to move from the areas with bad environment and high sediment yield to the areas with more comfortable environment and less sediment yield.The natural factors have greater influence on sediment yield of western region than that of eastern region.Generally,the natural factors play a dominant role on sediment yield in the Upper Yangtze River. 相似文献
76.
China has made great progress in the study of socio-economic water cycle. She has completed national water resources appraisement and medium to long-term water supply planning. She has been engaging in study on water-deficient regions in North China and Northwest China for about half a century. For solving water shortage problem in northern China, she has put forward the famous South-to-North Water Transferring Projects, which has been set as one of the four biggest national projects in the Tenth Five-Year-Plan period although there are still debates. For promoting water use efficiency, China has been reforming her water management system, including water right system and water price system. There has already been a case of water right purchase. China has also done a lot of research on the interaction between human activity, water and ecosystem. For meeting the need of sustainability and coordinating water resources development and environmental protection, the study of ecological water requirement became very hot in recent years. There are three focuses of socio-economic water cycle study now in China: water transfer projects from the south to the north, water resources management and ecological water requirement. 相似文献
77.
The Mersey Basin has been significantly polluted for over 200 years. However, there is a lack of quantitative historical water quality data as effective water quality monitoring and data recording only began 30–40 years ago. This paper assesses water pollution in the Mersey Basin using a Water Pollution Index constructed from social and economic data. Methodology, output and the difficulties involved with validation are discussed. With the limited data input available the index approximately reproduces historical water quality. The paper illustrates how historical studies of environmental water quality may provide valuable identification of factors responsible for pollution and a marker set for contemporary and future water quality issues in the context of the past. This is an issue of growing research interest. 相似文献
78.
The aquatic weed Eichhornia crassipes [Mart.]Solms was introduced in Lake Victoria from Rwanda via the Kagera River by the activities of man. After originally infesting Lake Victoria (Uganda), it eventually spread into the Winam gulf, where its proliferation was spectacular, resulting in an enormous public outcry. The aim of this study was to find out how a beach/bay covered by a weed carpet affected the life of a lakeshore community, if there were any seasonal changes in carpet sizes and to establish if the water hyacinth is a friend or an enemy. Surveys were conducted in selected beaches between June 1995 and November 1999. When surveys were complete, it became clear that this weed is nomadic, except in lagoons and beaches that had little external interference. The open waters remained generally clear due to constant wave action. Interviews conducted on selected beaches/bays indicated that weed carpets impacted both positively and negatively, i.e. they disrupted fishing activities, transport, irrigation, water treatment, enhanced breeding grounds for vectors of human diseases, impacted on biodiversity and had become a source of raw materials for making furniture, paper and artefacts. After successful biological control by the Kenya Agricultural Research Institute (KARI), resurgence and succession were observed. The impact of water hyacinth on the life of the lakeshore communities in the Winam gulf is serious and needs to be quantified. Further research is necessary to establish whether this weed is an enemy or a friend of the lakeshore communities. 相似文献
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80.
辽中地区矿业城市是我国重要的能源生产和重工业基地,研究其生态承载力状况并预测其发展趋势,有利于区域经济、生态协调发展。基于资源保障率、环境承载力和社会经济增长相统一的原则,运用系统动力学方法建立了辽中地区矿业城市生态承载力评价模型,评价了1997-2006年研究区生态承载力状况,预测了2006-2020年研究区生态承载力变化趋势。结果表明:1997-2006年,辽中地区矿业城市生态承载力总体处于超载状态,但发展趋势差别显著。鞍山生态承载力指数从1.686下降到1.301,年均下降2.56%,但仍处于超载状态;抚顺生态承载力指数从1.169下降到0.909,年均下降2.49%,生态承载力从超载变为盈余;本溪生态承载力指数从1.070上升到1.249,年均上升1.56%,超载程度不断加大。2006-2020年,辽中地区矿业城市生态承载力总体上处于超载程度加大的趋势,鞍山、抚顺和本溪生态承载力指数年均增长率分别达到0.89%、1.56%和1.81%。作为矿业城市,鞍山、抚顺和本溪需要优先保障水资源和能源的供需平衡,改善水环境质量,从而达到生态承载力的提高。 相似文献