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排序方式： 共有88条查询结果，搜索用时 31 毫秒
61.
Ron Mahabir Peggy Agouris Anthony Stefanidis Arie Croitoru Andrew T. Crooks 《International Journal of Digital Earth》2020,13(6):683-707
ABSTRACTThe worldwide slum population currently stands at over one billion, with substantial growth expected in the coming decades. Traditionally, slums have been mapped using information derived mainly from either physical indicators using remote sensing data, or socio-economic indicators using census data. Each data source on its own provides only a partial view of slums, an issue further compounded by data poverty in less-developed countries. To overcome such issues, this paper explores the fusion of traditional with emerging open data sources and data mining tools to identify additional indicators that can be used to detect and map the presence of slums, map their footprint, and map their evolution. Towards this goal, we develop an indicator database for slums using open sources of physical and socio-economic data that can be used to characterize slum settlements. Using this database, we then leverage data mining techniques to identify the most suitable combination of these indicators for mapping slums. Using three cities in Kenya as test cases, results show that the fusion of these data can improve the mapping accuracy of slums. These results suggest that the proposed approach can provide a viable solution to the emerging challenge of monitoring the growth of slums. 相似文献
62.
中国水资源对区域社会经济发展的支撑能力 总被引：14，自引：3，他引：11
综合考虑区域自产水和上游来水条件,构建了水资源支撑指数(WSPI),定量描述区域水资源短缺程度,表征水资源条件对区域社会经济发展的支撑能力。通过构建全国评价模型,计算了210 个水资源三级区以及省、县两级行政单元的WSPI。据此划分了水资源支撑能力等级,探讨了我国水资源支撑能力空间格局,分析了其与人口、GDP指标的关系,着重讨论了缺水区域空间分布及其缺水机理的差异性。该方法评价结果与我国实际水资源短缺问题基本一致,表现了较强的适用性,可以为水资源政策制定以及社会经济发展规划等宏观决策提供科学支撑。 相似文献
63.
Urban expansion and its influencing factors in Natural Wetland Distribution Area in Fuzhou City, China 总被引：2，自引：1，他引：1
This paper principally focuses on land use dynamics,urban expansion and underlying driving forces in the Natural Wetland Distribution Area(NWDA)of Fuzhou City in the southeastern China.Based on time series Landsat TM/ETM+imageries and historical data,relationships between urban land expansion and its influencing factors from 1989 to 2009 were analyzed by using an integrated approach of remote sensing(RS)and geographic information system(GIS)techniques.The results showed that built-up land increased from 151.16 km2in 1989 to 383.76 km 2in 2009. Approximately 64.25%of the newly emerging built-up land was converted from cropland(29.47%),forest and shrub (25.78%),water(3.73%),wetland(4.61%),and bare land(0.66%)during 1989 and 2009.With a remarkable decrease in cropland,the proportion of non-agricultural population increased by 23.6%.Moreover,rapid development of infrastructures,facilities,industrial parks,and urban and rural settlements along the Minjiang River resulted in the eastward and southward expansion of built-up land.Additionally,the growth pattern of built-up land in the NWDA is highly correlated with socio-economic factors,including the gross domestic product(GDP),GDP per capita,and structure of industry.As a result,the observed environmental degradation such as loss of cropland and wetland due to heavy pressure of rapid urbanization have greatly impaired the carrying capacity of city.Thus,in addition to scientific and rational policies towards minimizing the adverse effects of urbanization,coordination between the administrative agencies should be urgently strengthened to balance the conflicts between urban development and ecological conservation to make sure the sustainable land use. 相似文献
64.
以上海青西地区为研究对象,研究社会经济发展对水环境影响与对策,结果显示：①1992～2008年,青西地区社会经济高速发展,GDP年均增长率21.6%,工业总产值年均增长率19.1%,外来人口显著增多,从2004年的4.7万人增长至2008年的7.9万人;②地处黄浦江上游水源保护区,青西地区工业发展受到限制,畜禽养殖场被关闭,为水源保护做出较大贡献,但与此同时水源保护也面临社会经济发展带来的较大压力,主要表现在工业污染、农业污染和生活污染等三个方面;③从产业结构升级、污水处理系统建设、农村面源污染治理、生态补偿机制建立等方面提出建议,以协调区域社会经济发展与水源保护。 相似文献
65.
66.
Cai Kui 《云南地理环境研究》1999,(Z1)
１ ＢａｃｋｇｒｏｕｎｄＹｕｎｎａｎｉｓａｂｏｒｄｅｒｐｒｏｖｉｎｃｅｗｉｔｈ２５ｍｉｎｏｒｉｔｉｅｓｉｎｓｏｕｔｈｗｅｓｔＣｈｉｎａ,ａｎｄｍｏｒｅｔｈａｎ９４％ｔｅｒｒｉｔｏｒｙｉｓｍｏｕｎｔａｉｎａｒｅａ．Ｗｉｔｈｄｉｆｆｅｒｅｎｔｌｉｖｉｎｇｅｎｖｉｒｏｎｍｅｎｔａｎｄｈｉｓｔｏｒｉｅｓｏｆｍｏｖｉｎｇａｎｄｄｅｖｅｌｏｐｍｅｎｔ,ｅａｃｈｍｉｎｏｒｉｔｙｈａｄｆｏｒｍｅｄｉｔｓｏｗｎｌｉｖｉｎｇａｎｄｐｒｏｄｕｃｔｉｏｎｐａｔｔｅｒｎｓ,ａｎｄｔｈｅｓｅｃｈａｒａｃｔｅｒｓａｒｅａｌｓ… 相似文献
67.
行政单元的社会经济统计数据与地理单元的要素数据之间存在空间不匹配的问题,很难满足自然与人文交叉学科研究的需要。本文首先对社会经济数据空间化指标和方法进行了总结,发现空间化研究主要集中在人口与国内生产总值指标,对资本存量、房屋等其他社会经济指标的空间化研究相对较少;根据空间化的思路和方法差异,可将空间化方法归纳为面积权重法、统计模型法和多源数据融合法三类。最后通过对比分析不同空间化方法的原理和优缺点可知：社会经济研究指标多样化、空间化精度要求的多元化和大数据应用的广泛化是社会经济数据空间化的发展趋势。同时,大数据等新的辅助数据源的出现为空间化精度的提高带来了契机,在社会管理精细化要求不断提高的背景下,社会经济数据空间化也越来越成为研究热点。 相似文献
68.
Rapidly increasing populations coupled with increased food demand requires either an expansion of agricultural land or sufficient production gains from current resources. However, in a changing world, reduced water availability might undermine improvements in crop and grass productivity and may disproportionately affect different parts of the world. Using multi-model studies, the potential trends, risks and uncertainties to land use and land availability that may arise from reductions in water availability are examined here. In addition, the impacts of different policy interventions on pressures from emerging risks are examined.Results indicate that globally, approximately 11% and 10% of current crop- and grass-lands could be vulnerable to reduction in water availability and may lose some productive capacity, with Africa and the Middle East, China, Europe and Asia particularly at risk. While uncertainties remain, reduction in agricultural land area associated with dietary changes (reduction of food waste and decreased meat consumption) offers the greatest buffer against land loss and food insecurity. 相似文献
69.
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
70.