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21.
地质灾害专题地图编制研究   总被引:1,自引:0,他引:1  
吕卫  宫辉力 《灾害学》1993,8(3):75-78
地质灾害专题制图是地质灾害系统研究成果的高层次综合。本文论述了地质灾害制图的目的、原则、特点、表示内容与方法,为规划决策提供地质灾害背景图件。  相似文献   
22.
综述了车辆事故紧急呼救技术的原理,从车辆事故检测识别技术、移动车辆定位技术、无线通信技术和地理信息系统几方面概述车辆事故紧急呼救技术的研究内容。进一步介绍车辆事故紧急呼救技术的国内外研究和应用现状,并从车辆事故识别技术、地图匹配及组合导航、集群通信及通信网络几方面总结并指出车辆事故紧急呼救技术的关键技术和难点。展望了车辆事故紧急呼救技术的发展趋势,并就我国发展车辆事故呼救技术的可行性和发展方向进行探讨。  相似文献   
23.
The EU Flood Directive 2007/60 requires the assessment and delineation of flood risk maps. The latter should provide the required knowledge for the development of flood risk management plans (FRMPs), that should deal with all features of risk management: e.g. preparation, protection and prevention, comprising also the phase of the flood forecasting and warning systems, in addition to the emergency management. The risk maps, delineated through the expert-drive qualitative (EDQ) approach currently adopted in several European countries, such as Italy, fail to represent the information base that needed by stakeholders for selecting the suitable objectives and designing the appropriate mitigation actions for flood risk management. In the EDQ approach, the flood hazard and the potential damage degree maps are combined by means of a matrix to obtain a qualitative flood risk map. However, the performance of the risk matrix is not usually rigorous validated and, therefore, presents limits, such as subjective and not careful explained interpretation of rating and poor resolution, (due to range compression), that can produce errors in comparative ranking of risk areas. In this context, this paper proposes the FloodRisk approach that aims to improve the efficacy of flood risk map overcoming the limits of EDQ approach in supplying the knowledge base that allow to analyze costs and benefits of potential mitigation measures. However, the proposed approach is also able to involve the citizens in the flood management process, enhancing their awareness. An application of FloodRisk procedure is showed on a pilot case in “Serio” Valley, (North Italy), and its strengths and limits, in terms of additional efforts required in its application compared with EDQ procedure, have been discussed focusing on the efficacy of the outcomes provided for the fulfillment of FRMPs. The results have demonstrated the ability of FloodRisk, respect to EDQ approach, to distinguish successfully different levels of vulnerability of exposure elements, thanks to the use of asset value and depth-damage curves, that allows a suitably evaluation of the effectiveness of risk mitigation strategies. In this light, a successfully application of a cost-benefit analysis of FloodRisk approach on a portfolio of alternative mitigation actions, (i.e. structural and non-structural measurements), has been demonstrated on the proposed study case. However, FloodRisk requires additional information, e.g. water depths assessment and assets values, and it needs a proper analysis and communication of the uncertainty in its results. Although they still exist limitations that impede, at present, the FloodRisk application without an adequate understanding and a critical consideration of the hazard, exposure and vulnerability characteristics of the study area, considerations are supplied on how the utilization of this approach can be maximized in the light of the next flood risk maps revision due by December 2019.  相似文献   
24.
The main aim of this article is to demonstrate a method of complex landscape analysis in order to estimate the landscape suitability for the construction of surface-flow wetlands (SFW) for wastewater treatment. This is a multilevel suitability analysis from a more general regional (landscape) assessment based on a map of landscape types (1:100,000) toward a detailed analysis based on aerial orthophotos and detailed soil maps (1:10,000). The assessment scheme consists of landscape classification according to the physical-chemical properties of landscape factors (soil conditions, landforms, hydrogeology, expert decisions concerning landscape values, and suitability analysis). The partial suitability values of SFWs are derived by summarizing expert values for landscape factors (each ranging from -1 to +1). By multiplying the summarized partial suitability values with nature protection values (ranging from 0 to 1), we obtain the final suitability value for each landscape type. Any kind of nature protection area has been considered nonsuitable and excluded at regional-level analysis. The results of the regional analysis demonstrate that suitability is distributed relatively equally over the study area. The high suitability potential (classified as "very suitable") is relatively evenly distributed in lowland regions throughout the country. The share of "very suitable" and "suitable" areas in different counties varies from 5 to 23% and 7 to 49%, respectively. The detailed analysis based on aerial orthophotos showed that areas suitable for SFWs can also be found within the areas determined to be unsuitable based on the less detailed map of landscape types, whereas differences are much greater between settlements chosen for the detailed suitability analysis.  相似文献   
25.
坡度图在滑坡研究中的应用   总被引:2,自引:0,他引:2  
王念秦 《灾害学》1991,6(3):66-70
本文阐述了坡度图的概念和作用;详细介绍了坡度尺、坡度图的作法、以及坡度图在兰州地区的应用结果;简要分析了斜坡坡度与滑坡的关系。  相似文献   
26.
国土空间规划体系构建工作已经全面展开,清晰详实的现状图和数据是摸清自然资源家底的重要基础,也是编制国土空间规划的重要支撑。而当前国土空间现状数据的用地分类标准、数据精度和应用目标等尚不统一。基于遥感影像、地理国情和互联网POI等多源数据进行国土空间现状一张图研究,综合现有用地分类标准和数据精度,构建青岛市国土空间规划现状一张图。在此基础上,探讨国土空间规划一张图应用方向,包括青岛市“三生空间”和资源环境研判分析,以及城镇建设适宜性、生态服务功能重要性和农业生产适宜性分析等内容。国土空间规划现状一张图的构建,对于明确资源利用上限与环境质量底线,规范国土空间规划数据,以及支撑国土空间规划编制和管理具有重要作用。  相似文献   
27.
Abstract:  Central America is exceptionally rich in biodiversity, but varies widely in the attention its countries devote to conservation. Protected areas, widely considered the cornerstone of conservation, were not always created with the intent of conserving that biodiversity. We assessed how well the protected-area system of Central America includes the region's mammal diversity. This first required a refinement of existing range maps to reduce their extensive errors of commission (i.e., predicted presences in places where species do not occur). For this refinement, we used the ecological limits of each species to identify and remove unsuitable areas from the range. We then compared these maps with the locations of protected areas to measure the habitat protected for each of the region's 250 endemic mammals. The species most vulnerable to extinction—those with small ranges—were largely outside protected areas. Nevertheless, the most strictly protected areas tended toward areas with many small-ranged species. To improve the protection coverage of mammal diversity in the region, we identified a set of priority sites that would best complement the existing protected areas. Protecting these new sites would require a relatively small increase in the total area protected, but could greatly enhance mammal conservation.  相似文献   
28.
为研究烟气羽流的时空混沌行为,本文从烟气羽流的N-S动量方程出发,根据浮力羽流的半经验公式,对方程中相应的项进行替代、化简,然后无量纲化,得到了以烟气羽流的动量通量m为系统状态矢量的单向耦合映象格子模型.计算了不同参数变化时,耦合周期窗口的时空行为发展,并且进行了李雅普诺夫指数λ计算.分析表明,开放系统中的烟气羽流会出现形态的多重性,包括时空混沌行为.这是由于烟气羽流系统内各种非线性作用的相互影响,也就是方程粘性项、浮力项和惯性项作用强弱对比的变化,以及系统行为发展的不可逆性所导致.  相似文献   
29.
ABSTRACT

Old cadastral maps represent a historical reference dataset for long-term land-use reconstructions. This study presents identification of inconsistencies in the nineteenth century Franziscean cadastre, one of the largest sets of old cadastral maps worldwide, by comparing three versions of the maps and written documents created in the same period. We identified all parcels and their land-use in the four sub-sources in six study areas. The overall share of inconsistencies among 5 771 identified parcels is 7.4%, with the biggest share of inconsistency in agroforestry and forestry classes. The most frequent inconsistencies are of ‘Not differentiable land use’ (n = 212) and ‘Different land-use’ categories across the sub-sources (n = 113). We conclude that the frequency of uncertainties in old cadastral maps may limit the validity of historical land-use reconstructions, affecting the eventual restoration and management efforts based on such data. We provide a summary for the use of Franziscean cadastre.  相似文献   
30.
滇黔桂地区土壤有机碳储量与影响因素研究   总被引:13,自引:1,他引:12  
土壤有机碳(SOC)库在陆地生态系统中具有重要作用.由于土壤剖面数量和采用的土壤图比例尺等的限制,目前土壤有机碳库估箅尚存在很大不确定性.为了提高SOC库估算的精确性,利用798个土壤剖面及1:50万土壤图估算了滇黔桂地区(云南省、贵州省和广西壮族自治区)的SOC储量,并采用逐步回归分析和通径分析方法分析了影响SOC密度的主要因子.结果表明,滇黔桂地区表土层(0-20 cm)和土壤剖面(0-100 cm)的SOC储量分别为4.39 Pg和10.91 Pg;SOC密度分别为56.2Mg·hm-2和139.8 Mg·hm-2.高于全国平均水平.环境因子(海拔、经度、纬度、气温和降雨)、成土母质和土地利用方式对表土层和土壤剖面SOC密度变异性的解释度分别为37.9%和30.7%;环境因子为影响SOC密度的主要因子.环境因子中.气温对SOC密度的影响大干降雨,其中气温和降雨的变化分别主要由海拔和纬度的变化引起的.除气温和降雨外,还有其它随海拔或经纬度而变化的因子也对SOC密度产生显著影响,这种影响要大于降雨的影响.  相似文献   
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