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121.
防震减灾中卫星遥感技术应用分析 总被引:10,自引:1,他引:9
卫星遥感技术在减轻自然灾害中发押了十分重要的作用,但也不得不指出,卫星遥感技术在防震减灾工作中,无论在国内或国外均尚未得到有效的应用。这一方面固然是由于地震事件十分复杂,地震孕育和发生的规律尚未搞清,难以发挥卫得遥感技术的作用,另一方面也由中以使用的卫星技术的分辨率还不够高,重复观察的周期长,限制了这一技术在防震减灾工作中的应用。有鉴于近感技术的分辨率还不够高,重复观察的周期长,限制了这一技术在防 相似文献
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运用遥感动态监测与地理信息系统技术相结合的方法,以2005年和2009年遥感解译数据、土地侵蚀数据及环境统计数据为数据源,依据《生态环境状况评价技术规范(试行)》(HJ/T192-2006),对山东省17个城市生态环境质量现状及动态变化趋势进行了评价。结果表明:2009年17个城市生态环境状况指数在59.81~78.08之间,生态环境质量状况总体良好;2005-2009年17城市生态环境状况指数变化值在0.06~3.5之间,生态环境质量状况基本稳定。 相似文献
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A comparison of current techniques for measuring elevations in the beach and near-shore zones is presented. Techniques considered
include traditional methods such as ground survey along transects and airborne stereophotogrammetry, and also newer methods
based on remote sensing such as airborne scanning laser altimetry (LiDAR). The approach taken was to identify a representative
group of users of beach elevation data, elicit their requirements regarding these data, then assess how well the different
methods met these requirements on both technical and financial grounds.
Potential users of beach height measurements include those concerned with coastal defence, coastal environmental management
economic exploitation of the intertidal zone, and coastal flood forecasting. Three test areas in the UK were identified covering
a range of such users and also different beach types. A total of 17 basic user requirements were elicited. For each requirement
each method was scored according to the degree to which it could meet the requirement. Total scores were calculated and each
method ranked. This was undertaken for all the requirements together, for a subset relating to survey of narrow beaches, and
for a subset relating to survey of wide beaches. Approximate costs were also established for the top six methods.
Airborne stereophotogrammetry proved to be the best method technically, but was also the most expensive. Ground survey provides
very good technical performance on narrower beaches at moderate cost. Airborne LiDAR can achieve good technical performance
on both narrow and wide beaches at lower cost than ground survey. The satellite-based waterline method was also inexpensive
and gave good results on wide beaches. An overall conclusion is that, while the traditional methods of ground survey and airborne
stereophotogrammetry remain the best for engineering-related surveys requiring high levels of accuracy, airborne LiDAR in
particular looks set to have a significant impact on beach survey for applications for which a vertical accuracy of 20 cm
is acceptable, provided that its technology evolves satisfactorily. 相似文献
127.
Montane Meadows as Indicators of Environmental Change 总被引:1,自引:0,他引:1
Diane M. Debinski Mark E. Jakubauskas Kelly Kindscher 《Environmental monitoring and assessment》2000,64(1):213-225
We used a time series of satellite multispectral imagery for mapping and monitoring six classes of montane meadows arrayed along a moisture gradient (from hydric to mesic to xeric). We hypothesized that mesic meadows would support the highest species diversity of plants, birds, and butterflies because they are more moderate environments. We also hypothesized that mesic meadows would exhibit the greatest seasonal and interannual variability in spectral response across years. Field sampling in each of the meadow types was conducted for plants, birds, and butterflies in 1997 and 1998. Mesic meadows supported the highest plant species diversity, but there was no significant difference in bird or butterfly species diversity among meadow types. These data show that it may be easier to detect significant differences in more species rich taxa (e.g., plants) than taxa that are represented by fewer species (e.g., butterflies and birds). Mesic meadows also showed the greatest seasonal and interannual variability in spectral response. Given the rich biodiversity of mesic montane meadows and their sensitivity to variations in temperature and moisture, they may be important to monitor in the context of environmental change 相似文献
128.
Monitoring urban growth and detecting land-cover changes on the Istanbul metropolitan area 总被引:1,自引:0,他引:1
Istanbul is the most populated city of Turkey with a population of around 10.58 M (2000) living on around 5,750 km2. In 1980, the population was only 4.7 M and then it has been more than doubled in only two decades. The population has been
increasing as a result of mass immigration. An urbanization process continues and it causes serious increases in urban areas
while decreasing the amount of green areas. This rapid, uncontrolled, and illegal urbanization accompanied by insufficient
infrastructure has caused degradation of forest and barren lands in the metropolitan area, especially through the last two
decades. The watershed basins inside the metropolitan area and the transportation network have accelerated the land-cover
changes, which have negative impacts on water quality of the basins. Monitoring urban growth and land cover change will enable
better management of this complex urban area by the Greater Istanbul Metropolitan Municipality (GIMM). A temporal assessment
of land-cover changes of Istanbul has been documented in this study. The study mainly focuses on the acquisition and analysis
of Landsat TM and Landsat GeoCover LC satellite images reflecting the significant land-cover changes between the years of
1990 and 2005. Raster data were converted to vector data and used in Geographic Information Systems (GIS). A database was
created for Istanbul metropolitan area to plan, manage, and utilize statistical attribute data covering population, water,
forest, industry, and topographic position. Consequently an overlay analysis was carried out and land use/cover changes through
years have been detected for the case study area. The capability of Landsat images in determining the alterations in the macro
form of the city are also discussed. 相似文献
129.
Existing and projected water shortages and related factors have helped focus attention on the need for water reuse. With recent technological advances in wastewater treatment, it is now possible to produce reclaimed water of any quality. Thus, the use of reclaimed water will depend on the reuse opportunities and the cost of the required infrastructure. Historically, centralized wastewater treatment facilities have served the needs of organized societies since the mid 1800s. However, as there are limited options for expansion of most existing centralized facilities, the use of satellite and decentralized wastewater management systems offers significant advantages including being close both to the source of wastewater generation and to potential water reuse applications. The comparative advantages of satellite and decentralized wastewater management systems for a number of water reuse applications are presented and discussed in this paper. Selected case studies are presented to demonstrate the utility of satellite and decentralized wastewater management. Specific issues associated with the application of such systems in existing and in new developments are examined and discussed. 相似文献
130.
以滁州市1966年的地形图,1978年、1987年、1995年、2000年及2006年的遥感影像为数据源,提取滁州市6个时段的建成区面积对其用地扩展进行了研究。结果表明,滁州市建成区面积在1966-2006年间面积增加了7.84倍,扩展速度经历了先快后慢的过程;发展方向以东南方向为主,40年间城市中心向东、南方向分别迁移了1084m和1940m对揭示安徽省中小型城市用地的发展特征具有一定意义。 相似文献