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131.
基于GIS的陕西省地质灾害信息系统设计   总被引:3,自引:1,他引:3  
徐春迪  郭俊理 《灾害学》2005,20(2):102-105
GIS技术在灾害研究中的应用日益广泛,GIS强大的空间分析功能和海量数据管理优势为地质灾害数据的管理分析、动态监测、机理模拟、预测预报、辅助决策提供了强有力的支持.本文从陕西地质灾害分析入手,设计了基于GIS的地质灾害信息系统,并对系统目标、系统总体设计、系统功能进行了分析.该系统可为陕西省地质灾害的管理和防治提供科学依据,减少经济损失.  相似文献   
132.
大气质量评价上海指数法的改进及应用   总被引:1,自引:0,他引:1  
该研究将模糊数学应用于上海指数法,在评价函数中引入半梯形隶属函数和倍斜率隶属函数,提出模糊上海指数法,将此法应用于延安市的大气质量评价工人,欧几里德贴近度法和上海指法的结果进行比较表明,模糊上海指数法的评价结果是科学合理的,并利用地理信息系统Mapinfo制作出基于地理信息的城市大气质量评价图,使评价结果可视化,地图化。  相似文献   
133.
南水北调对湖北丹江口水库区土地资源的影响   总被引:6,自引:1,他引:6  
湖北省丹江口水库区是南水北调中线工程的水源区。随着调水工程的实施,库区土地资源将受到深远的影响。以丹江口水库及其四周海拔低于200m的区域为研究范围,选用90年代初获取的LandsatTM假彩色合成图像为主信息源,运用目视判读和地理信息系统(GIS)方法,对该区的土地资源利用现状进行了比例尺为25万分之一的遥感制图和计算机面积量算;在此基础上,对工程实施后本区土地资源的淹没损失、土地利用结构的变化进行了宏观分析,进而对区域土地资源的合理利用进行了初步探讨。  相似文献   
134.
Tourism is the way we understand the world: tourists travel in an increasingly mediated environment in which ubiquitous promotional material and other popular artifacts employ stunning images and romantic travel narratives to describe local environments. Tourist texts “sell” local landscapes to entice visitors, employing an environmental aesthetic that urges travel. With its mission to “explore the planet,” the National Geographic Society contributes to this tourist aesthetic. This essay examines three special issues on Africa simultaneously published by the National Geographic Society: its official journal, National Geographic, and its sister magazines, National Geographic Traveler, and National Geographic Adventure. The photographic images and travel narratives in these tourist texts produce an environmental aesthetic that positions the traveler at the center of these environments. This essay first analyzes how National Geographic constructs Africa's environmental landscapes. These magazines depict Africa as a vast desert plain, a wilderness theme park, and a part of the global scenery. The second part of the analysis examines how National Geographic locates the tourist in these environments. I discuss how National Geographic positions the tourist as protagonist, expert, and hero of Africa's environment. In the conclusions, I argue this environmental aesthetic renders Africa invisible through anthropocentric distance, and I discuss the need for more critical readings of tourist discourse.  相似文献   
135.
This paper aims at studying the dynamic mechanism of urban expansion and its role. Based on the economic model of urban spatial structure and applying panel data in Shandong Province, the paper concludes. Economic growth and transition of economic structure have played the most powerful role in urban expansion. An increase in population helps the core to extend. Increasing agricultural productivity can provide a countervailing force. An increase in transportation costs will limit urban expansion. An increase in the marginal productivity of land in housing production will increase urban expansion. Fiscal and taxation policies also have encouraged the extensive shift of cultivated land into build-up area. This paper also suggests that if high rate increasing GDP is needed, the urban core will continue to expand. The government should take measures to improve the rapid growth of the city.  相似文献   
136.
Assessments of large-scale changes in habitat are a priority for management and conservation. Traditional approaches use land use and land cover data (LULC) that focus mostly on “structural” properties of landscapes, rather than “functional” properties related to specific ecological processes. Here, we contend that designing functional analyses of LULC can provide important and complementary information to traditional, structural analyses. We substantiate this perspective with an example of functional changes in habitat due to industrial anthropogenic footprints in Alberta’s boreal forest, where there has been little overall forest loss (~ 6% structural change), but high levels of functional change (up to 93% functional change) for species’ habitat, biodiversity, and wildfire ignition. We discuss the methods needed to achieve functional LULC analyses, when they are most appropriate to add to structural assessments, and conclude by providing recommendations for analyses of LULC in a future of increasingly high-resolution, dynamic remote sensing data.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01434-5) contains supplementary material, which is available to authorized users.  相似文献   
137.
小城镇基础设施防灾减灾决策支持系统的研究与开发   总被引:15,自引:5,他引:15  
利用信息技术研究灾害问题成为研究热点之一 ,但在小城镇防灾减灾方面仍缺少应有的关注和重视。笔者将地理信息系统 (GIS)和决策支持系统 (DSS)集成应用于开发“基于GIS的小城镇基础设施防灾减灾决策支持系统” ,简要介绍了该系统研制目标和原则、系统结构框架及各子系统的功能 ,解决了系统实现过程中的一系列关键技术 :快速、高效构建小城镇基础空间数据库及三维可视化、应急预案及历史灾情库的电子化及各类灾害分析模拟的专业模型等。实践证明 ,基于基础设施、灾害源、防护保卫目标、应急救援力量的可视化与数字化 ,该系统能够实现对其进行科学管理、对各单一灾种的模拟分析以及应急决策支持 ,有效提高小城镇政府的应急指挥决策水平 ,增强其灾害应急反应能力。  相似文献   
138.
An approach to transportation risk analysis for road and rail transport of dangerous goods is proposed, which is based on the use of geographic information systems (GIS) to manage territorial information, coupled with a product data bank in a risk evaluation tool. Such an approach enables to accurately take into account the local data affecting risk analysis, such as population, accident rate, and weather conditions along all the route, by means of a system which can be easily updated. The resulting risk evaluation tool assists in the step of route identification and allows to rapidly perform an accurate transportation risk analysis, for a single transportation event as well as for multiple substances, trips and itineraries.  相似文献   
139.
为增加有效降水,降低干旱和雾霾等环境污染的影响,保护生态环境安全,研制了以提高开发空中水资源能力为主要目的、基于GIS技术的人工增雨作业决策指挥系统,依托新一代多普勒天气雷达、Micaps数据资料和自动站数据库,应用Microsoft C#语言开发了增雨作业预警和指挥功能、指挥信息和作业信息收集互传功能、增雨效果评估功能、常规业务管理功能,构建了功能较为完善的业务系统。  相似文献   
140.
Estimation of stream channel heads is an important task since ephemeral channels play a significant role in the transport of sediment and materials to perennial streams. The slope‐area method utilizes digital elevation model (DEM) and related information to develop slope‐area threshold relationships used to estimate the position of channel heads in the watershed. A total of 162 stream channel heads were mapped across the three physiographic regions of Alabama, including the Southwestern Appalachians (51), Piedmont/Ridge and Valley (61), and Coastal Plains (51). Using Geographic Information System and DEM, the local slope and drainage area for each mapped channel head was calculated and region‐specific models were developed and evaluated. Results demonstrated the local slope and drainage area had an inverse and strong correlation in the Piedmont/Ridge and Valley region (r2 = 0.71) and the Southwestern Appalachian region (r2 = 0.61). Among three physiographic regions, the weakest correlation was observed in the Coastal Plain region (r2 = 0.45). By comparing the locations of modeled channel heads to those located in the field, calculated reliability and sensitivity indices indicated model accuracy and reliance were weak to moderate. However, the slope‐area method helped define the upstream boundaries of a more detailed channel network than that derived from the 1:24,000‐scale National Hydrography Dataset, which is commonly used for planning and regulatory purposes.  相似文献   
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