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991.
基于GIS的洪水淹没评估系统的研究与实现 总被引:5,自引:4,他引:1
在G IS技术支持下,对洪水淹没评估系统从洪水淹没计算与洪水淹没评估两方面进行研究,结合湖南冷水滩区洪水淹没评估系统实例,选择了正方形DEM模型,利用正方形格网分析方法进行了洪水淹没中连通性的分析。构建了洪水淹没评估模型,并对洪水淹没评估中的叠置分析提出具体解决思路。最后介绍了系统的设计与实现。 相似文献
992.
A Multi‐Scale Analysis of Low‐Rise Apartment Water Demand through Integration of Water Consumption,Land Use,and Demographic Data
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Saeed Ghavidelfar Asaad Y. Shamseldin Bruce W. Melville 《Journal of the American Water Resources Association》2016,52(5):1056-1067
Over the past decades, multi‐unit housing developments have been vastly expanded across urban areas due to the population growth. To properly supply water to this growing sector, it is essential to understand the determinants of its water use. However, this task has largely remained unexplored through the empirical study of water demand mainly due to the scarcity of data in this sector. This study integrated apartment water consumption, property characteristics, weather, water pricing, and census microdata to overcome this issue. Using a rich source of GIS‐based urban databases in Auckland, New Zealand, the study developed a large dataset containing the information of 18,000 low‐rise apartments to evaluate the determinants of water use both in the household scale and aggregated scale. The household‐scale demand analysis helped to assess the heterogeneity in responses to the demand drivers specifically water price across different consumer groups, whereas the aggregated analysis revealed the determinants behind the spatial variation in water demand at the census area unit level. Through applying panel data models, the study revealed the household size as the most important determinant of apartment water use in Auckland, where other socioeconomic factors, building features, and water pricing were not significant determinants. This knowledge of determinants of water demand can help water planners to better manage water demand in the compact urban environments. 相似文献
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应用证据权重法结合GIS空间分析,研究了呼伦贝尔地区人为草原火险。利用证据权重法定量化地分析了与人类活动密切相关的5个因子(乡村人口密度、载畜密度、居民点分布、城镇分布、公路网)与草原火点空间分布的关系,并建立了呼伦贝尔草原火险预测模型,据此在ARCVIEW的WofE扩展模块下生成一幅草原火险预测专题图,并将研究区划分为高、中、低三类风险区。研究表明:(1)呼伦贝尔草原火灾火点的空间分布与人类活动关系密切,尤其是乡村人口密度、公路网与居民点分布这三个因子,权重分别为0.5191,0.1945,0.2864;(2)证据权重法可以客观定量地表现出草原火险与人类活动的关系,因而可为草原火灾风险管理提供决策支持。 相似文献
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Weili Duan Bin He Kaoru Takara Pingping Luo Daniel Nover Netrananda Sahu Yosuke Yamashiki 《Chemosphere》2013
We present a spatiotemporal evaluation of water quality incidents in Japan considering incident numbers, incident causes, pollutant categories, and pollution effects. Water pollution incidents in first-class river systems almost tripled to about 1487 in the 12 years from 1996 to 2007. In addition, oil makes up the largest proportion of pollutants nationwide (76.61%) and the major source of pollution for each region in Japan. Moreover, every category shows a growth trend, especially since 2005. The main cause of incidents was “Unknown” (43%), followed by “Poor working practice” (24%), and then by “Accident” (10%) and “Other” (10%). In Hokuriku, however, the main cause of incidents was “Poor working practice” (36%), which is greater than “Unknown” (30%). Finally, waterworks (approximately 60%) was the largest of four kinds of water supply infrastructure affected by pollution incidents, followed by simplified waterworks. The population affected by offensive odors and tastes peaked in 1990 and has been decreasing. Overall, the results show the characteristics of incidents from 1996 to 2007, with significant implications for adaptation measures, strategies and policies to reduce water quality incidents. 相似文献
997.
采用GIS技术,根据高程、坡度、土壤类型等环境特征,将乌东德水库坝前段消落带分为18种生态类型,并完成了高程图、坡度图和土壤类型图,建立了环境特征和消落带类型的直观联系。然后根据不同的生态类型,提出了4种生态修复模式,并选择了10种植物作为生态修复物种。为其它水库消落带生态修复提供了参考依据。 相似文献
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Salve PR Satapathy DR Katpatal YB Wate SR 《Environmental monitoring and assessment》2007,133(1-3):87-98
Stratospheric input and photochemical ozone formation in the troposphere are the two main sources determining the ozone levels
in the surface layer of the atmosphere. Because of the importance of ozone in controlling the atmospheric chemistry and its
decisive role in the heat balance of atmosphere, leading to climate change, the examination of its formation and destruction
are of great interest. This study characterized the distribution of Ground level Ozone (GLO) in Chandrapur district is lying
between 19°25′N to 20°45′N and 78°50′E to 80°10′E. Continuous ozone analyzer was used to quantify GLO at thirteen locations
fixed by Global Positioning System (GPS) during the winter of 2005–2006. The daily GLO at all the locations ranged between
6.4 and 24.8 ppbv with an average and standard deviation of 14.9 ± 6.5 ppbv. The maximum and minimum concentration occurs
during 1300–1600 h and 0300–0500 h may be due to high solar radiation facilitating photochemical production of O3 and downward mixing from the overlying air mass and in situ destruction of ozone by deposition and/or the reaction between
O3 and NO. GIS based spatial distribution of GLO in Chandrapur district is indicates that the central core of the district and
southern sites experienced elevated levels of GLO relative to the northern and western areas. The sites near by Chandrapur
city are particularly affected by elevated GLO. The average variation of GLO with temperature shows a significant correlation
of r = 0.55 indicating a direct relationship between GLO and temperature. Similarly an attempt has been made to compare the GLO
monitored data in Chandrapur district with the reported values for other locations in Indian cities. This generated database
helps regulatory agencies to identify locations where the natural resources and human health could be at risk. 相似文献
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