Comparison on Vulnerability of European and Chinese Air Transport Networks under Spatial Hazards

European air transport network(EATN)and Chinese air transport network(CATN),as two important air transport systems in the world,are facing increasingly spatial hazards,such as extreme weathers and natural disasters. In order to reflect and compare impact of spatial hazards on the two networks in a practical way,a new spatial vulnerability model(SVM)is proposed in this paper,which analyzes vulnerability of a network system under spatial hazards from the perspectives of network topology and characteristics of hazards. Before introduction of the SVM,two abstract networks for EATN and CATN are established with a simple topological analysis by traditional vulnerability method. Then,the process to study vulnerability of an air transport network under spatial hazards by SVM is presented. Based on it,a comparative case study on EATN and CATN under two representative spatial hazard scenarios,one with an even spatial distribution,named as spatially uniform hazard,and the other with an uneven spatial distribution that takes rainstorm hazard as an example,is conducted. The simulation results show that both of EATN and CATN are robust to spatially uniform hazard,but vulnerable to rainstorm hazard. In the comparison of the results of the two networks that only stands from the points of network topology and characteristics of hazard without considering certain unequal factors,including airspace openness and flight safety importance in Europe and China,EATN is more vulnerable than CATN under rainstorm hazard. This suggests that when the two networks grow to a similar developed level in future,EATN needs to pay more attention to the impact of rainstorm hazard.

Spatial Analysis of Risks and Vulnerabilities to Major Hazards in Madagascar Using the Multi-Criteria Method Based on the Analytical Hierarchy Process (AHP)

Natural disasters are not negligible factors that have significant impacts on a country’s development. Madagascar cannot escape cyclones, floods and drought due to its geographical situation. The objective in this work is to assess the risks and vulnerability to these hazards in order to strengthen the resilience of the Malagasy population. Our approach is based on multi-criteria spatial analysis using the Analytical Hierarchy Process (AHP). The results form decision spatial information that can be used at the strategic level of natural risk and disaster management. This work focuses on the degree of vulnerability and it was found in this study that the Androy and Atsimo-Atsinanana regions are the most vulnerable to major hazards in Madagascar not only because of their exposure to risk but also because of their very low socio-economic status.

Integration of Geological, Geophysical and Seismological Data for Seismic Hazard Assessment Using Spatial Matching Index

Probabilistic seismic hazard assessment (PSHA) takes into account as much data as possible for defining the initial seismic source zone model. In response to this, an algorithm has been developed for integration of geological, geophysical and seismological data through a spatial index showing the presence or absence of a potential seismic source feature in the input data. The spatial matching index (SMI) is calculated to define the coincidence of independent data showing any indications for existence of a fault structure. It is applied for hazard assessment of Bulgaria through quantification of the seismic potential of 416 square blocks, 20 × 20 km in size covering the entire territory of Bulgaria and extended by 20 km outside of the country borders. All operations are carried out in GIS environment using its capabilities to work with different types of georeferenced spatial data. Results show that the highest seismic potential (largest SMI) is observed in 56 block elements (13% of the territory) clearly delineating cores of the source zones. Partial match is registered in 98 block elements when one of the features is missing. Not any evidence for earthquake occurrence is predicted by our calculation in 117 elements, comprising 28% of the examined area. The quantitative parameter for spatial data integration which is obtained in the present research may be used to analyze information regardless of its type and purpose.

Regional Integrated Meteorological Forecasting and Warning Model for Geological Hazards Based on Logistic Regression

Information model is adopted to integrate factors of various geosciences to estimate the susceptibility of geological hazards. Further combining the dynamic rainfall observations, Logistic regression is used for modeling the probabilities of geological hazard occurrences, upon which hierarchical warnings for rainfall-induced geological hazards are produced. The forecasting and warning model takes numerical precipitation forecasts on grid points as its dynamic input, forecasts the probabilities of geological hazard occurrences on the same grid, and translates the results into likelihoods in the form of a 5-level hierarchy. Validation of the model with observational data for the year 2004 shows that 80% of the geological hazards of the year have been identified as ＂likely enough to release warning messages＂. The model can satisfy the requirements of an operational warning system, thus is an effective way to improve the meteorological warnings for geological hazards.

Status and Spatial Visualization of Toxic Pollutants (BTEX) in Urban Atmosphere

This is a study of visualization of positive data of by Positive Modified Quadratic Shepard (PMQS) method. This data visualization tool was implemented successfully in MATLAB using both recorded pollutants levels and geological coordinates of data acquisition points located in different localities of the metropolitan. These points were located in/around the potential air emissions sources like vehicular transport, industrial sector and residential sector dispersed all around the city Field measurements were carried for 12 hour (day time) at eight points each. An online VOC analyzer was used during field campaign to collect data of hazardous organic pollutants like benzene, toluene, ethyl benzene, xylene (BTEX). Constant concentration curves were generated in form of contour plots showing latitude, longitude and spatial distribution of recorded atmospheric pollutants.

Spatial Analysis of Affected Areas by Extreme Hydrological Events in Rio de Janeiro (The Host City for the 2016 Olympic Games)—Brazil

The most frequent types of disasters in Brazil are associated with extreme hydrological events. Adding to this situation, in Brazil, there are the extreme sociospatial discrepancies that are historically constructed. They leave marks in space, making specific areas, for political interest or not, more vulnerable to the different mentioned processes. To this extent, the public management should plan actions and, also, it may act in a more holistic way adding new trends, such as, the use of geotechnologies that are applied to environmental management in the realm of urban planning. From a case study in the city of Rio de Janeiro, this paper aims to contribute and draw attention to such issues. It may reach its target through pointing and spatially analyzing which areas are in the most critical situation related to the occurrence of extreme hydrological events. To achieve this goal, it was proposed a methodology to inventory the occurrence of inundation/flooding for a certain period, in this case 2001-2008. Besides, the methodology could systematize data and integrate them with other important issues for supporting the process of identification and analysis of the most critical areas. Historical aspects of occupation and the most vulnerable socio-environmental aspects were raised, too, in order to validate the highlighted areas. This integration was enabled concerning the support of geoprocessing techniques. The results of this integration subsidized the mapping and spatial analysis of the affected areas in the city and the criticality in relation to the extreme hydrological events. Finally, it was possible to observe that the identification of the most critical affected areas does not mean the exhaustion of the subject. The location of these areas is directly linked to the sample that was used as the basis for analyses. This data set only represents recorded events by the Municipal Civil Defense respecting the studied time frame. However, the results permit to take notes and raise relevant environmental questions about the roots and the occurred impacts that were originated from the extreme hydrological events, which have been observed in recent decades.

Spatial Genetic Structure of Two HIV-I-resistant Polymorphisms (CCR2-64 Ⅰ and SDF1-3’A) Alleles in Population of Shandong Province, China

To explore the spatial genetic structure of two HIV-Ⅰ-resistant polymorphisms （CCR2-64 Ⅰ and SDF1-3＇A） alleles in the population of Shandong Province, China. Methods Using the techniques of spatial stratified sampling and spatial statistics, the spatial genetic structure of the locus （CCR2-64 Ⅰ and SDF1-3＇A）, which was shown to be important co-receptor for HIV infection, was quantified from the populations of 36 sampled counties of Shandong Province, and a total of 3147 and 3172 samples were taken for testing CCR2-64Ⅰ and SDF1-3＇A respectively from individuals without known history of HIV-Ⅰ infection and AIDS symptoms. Results There were significantly spatial genetic structures of the two alleles at different spatial distance classes on the scale of populations, but on the scale of individuals, no spatial structure was found in either the whole area of Shandong Province or the area of each sampled county. Although the change of frequencies of the two alleles with geographic locations in Shandong Province both showed gradual increase trends, their changing directions were inverse. The frequency of CCR2-64Ⅰallele gradually increased from the southwest to the northeast, while the frequency of SDF1-3＇A allele gradually increased from the northeast to the southwest. However the RH to AIDS of combined types of their different genotypes did not represent obvious geographic diversity on the whole area of the Province. Conclusion The frequency of allele usually has some spatial genetic structures or spatial autocorrelation with different spatial distance classes, but the genotypes of individuals have random distribution in the same geographic area. Evaluating spatial distribution of the genetic susceptibility of HIV （AIDS） to CCR2-64Ⅰand SDF1-3＇A alleles, should focus on the frequencies of combined genotypes of CCR2 and SDFI based on the two-locus genotypes of each individual rather than the frequencies of CCR2-641 and SDF1-3＇A alleles.

基于小班尺度的北京市密云区森林火灾危险性评价

【目的】森林火灾危险性评价是实现科学林火管理工作的重要前提和基础,基于小班尺度开展森林火灾危险性评价及其空间特征分析,可为林火精细化管理提供依据。【方法】以密云区为研究对象,基于2019年森林资源二类调查小班数据、森林可燃物数据、气象数据、重要火源点等数据,构建密云区森林火灾危险性评价体系,应用层次分析法和熵权法相结合的主客观赋权法确定评价体系中各指标权重,根据评价体系中最终权重采用加权综合评价法计算各小班的危险性指数,依据自然断点分级法划分为高、中高、中低、低4个等级;采用全域和局域莫兰指数判断各小班之间的空间自相关性和聚集分布特征。【结果】(1)基于小班尺度综合4类因子构建体系,权重分布比例合理,可较好地开展火灾危险性评价;(2)研究区内高等级、中高等级、中低等级、低等级危险性的小班面积占比分别为12.75%,19.01%,41.70%,26.54%。其中,高等级危险性小班以灌木林、侧柏林、油松林为主,小班面积占比分别为38.40%、25.76%、24.13%;(3)高等级危险性小班分布在研究区范围的东部以及中南部区域,从乡镇尺度分析,呈片状分布于巨各庄镇、高岭镇和新城子镇;(4)小班危险性的全域莫兰指数为0.2413(大于0),说明密云区各小班存在一定的正相关性,即小班呈现出聚集分布的特征,采用局域莫兰指数分析发现火灾危险性等级为高-高聚集型小班的面积达34637.77 hm^(2),占密云区面积的15.56%。【结论】(1)构建的森林火灾危险性评价体系中,野外火源所占权重最大,是影响森林火灾危险性的主要因素;(2)高等级危险性小班区域灌木林占比较高,且聚集分布特征明显,根据权重结果,建议增强对野外火源和重点人群的监督和管理;另一方面,制定可燃物清理的标准和要求,定期在农林交错地区和火源点周围进行可燃物清理作业。

基于精细化空间格局的城市承灾体脆弱性评估

针对目前流域内部跨行政区单元空间精细化模拟并用于评估城市洪涝灾害工作的空白,本文着重聚焦精细化经济指标空间分布并将多源数据融合,构建了基于精细化空间格局的城市承灾体脆弱性评估体系,量化了深圳河流域脆弱性等级。研究结果表明:单一数据不足以准确模拟流域GDP密度,结合多源数据是进行GDP空间精细化更加有效的办法;深圳河流域GDP密度与第二、三产业空间化结果显示出高度一致性,产值密度最高达617214万元/km^(2);流域两岸脆弱性等级存在显著差异和区域特征,深圳侧脆弱性明显高于香港侧,高脆弱性地区约占流域面积的8.8%。研究结果有助于识别灾害危险性大小和损失程度,提高城市洪涝灾害评估的精确性。

雅砻江流域深切河谷区滑坡类型、成因及分布规律——以子拖西―麻郎错河段为例

【研究目的】雅砻江流域是中国西部重要的林牧业基地、水电能源基地和少数民族聚居区,开展流域内的滑坡成因和分布规律研究,对于制定科学的防灾减灾策略、保障经济社会稳定发展具有重要意义。【研究方法】以雅砻江中游深切河谷区子拖西―麻郎错河段为研究区,通过高分辨率卫星遥感解译、InSAR分析、结合现场调查获取滑坡基础数据;采用工程地质分析方法总结分析典型的滑坡类型及其成因机制;利用GIS空间分析和统计方法,揭示滑坡的分布规律及发育的优势范围。【研究结果】(1)研究区内共查明滑坡606处,其中面积104~105m^(2)的滑坡数量最多,约占总数的60%;面积103~104m^(2)和面积105~106m^(2)的滑坡数量相当,各约占总数的20%;(2)根据主控诱发因素将滑坡划分为降雨诱发型、构造控制型、开挖诱发型、河流侵蚀型和蓄水诱发型等5种主要类型;降雨和蓄水对岩土体强度的弱化效应、断裂构造对岩体结构及其力学性质的劣化效应、开挖和河流侵蚀对斜坡前缘抗滑支撑作用的解除效应等是导致滑坡形成的关键机理;(3)海拔高程2500~3500 m、坡度15°~35°、坡向NE-E和S-W是滑坡发育的优势地形范围;(4)由薄层状板岩、粉砂质板岩构成的软变质岩组是滑坡发育的优势岩组,花岗岩、石英闪长岩等坚硬侵入岩构成的岩浆岩组中滑坡最不发育;(5)康都断层、千杯尼玛断层、祝桑断层、唐岗断层、霍泽扎日断层和涅达断层这6条断层对滑坡的影响不显著,研究区下游麻子石断层、程章断层、然公断层、鸡打—米龙—木灰断层两侧及其交汇部位滑坡发育最为密集;(6)滑坡发育分布与河流水系距离之间呈明显的负相关性,距河流水系0~0.5 km是滑坡发育的优势距离,宏观上滑坡沿着河谷成带状集中分布。【结论】研究成果可以为认识雅砻江深切河谷区滑坡的成因和规律,防控流域链式灾害风险提供重要的科学依据。

广东省地质灾害隐患空间分布格局研究

广东省地质灾害易发多发,为全国地质灾害严重省份之一。基于GIS的地质灾害隐患点空间分布格局研究可以挖掘出广东省地质灾害隐患的空间异质性与空间自相关性等空间信息,支撑广东省地质灾害识别与防治需求。基于广东省多年地质灾害隐患点数据,利用GIS的多元空间统计与分析方法,从数量、时间、密度、聚类和地形五个方面综合分析广东省地质灾害隐患点的空间分布格局。结果表明:广东省地质灾害主要以崩塌和滑坡为主,粤北山区最多发,梅州市地质灾害隐患点数量最多,河源市威胁程度最大。地质灾害隐患多发于上半年,6月和8月为最高发月份。东部地质灾害隐患点密度远高于其他地区,在东北部呈现出高-高聚类模式。高程0~200m,坡度10°~20°,坡向朝南为易发地形区间。

我国地质灾害时空分布特征及演变分析

本文分析了2011-2020年我国地质灾害时空分布特征及其重心移动轨迹。基于2012-2021年《中国统计年鉴》中的地质灾害灾情数据,使用分级地图展示地质灾害时空分布,再运用全局和局部空间自相关分析探讨地质灾害的空间关联性和聚集特征,最后利用ArcGIS平台对地质灾害的重心移动轨迹进行分析。结果表明:我国地质灾害的发生虽然总体呈下降趋势,区域分布呈“南多北少”态势,但空间聚集性逐年增强,且西南地区高-高聚集区域不断扩大,应对地质灾害高发区进行重点防控。

青海省湟水流域潜在地质灾害识别与易发性评价

[目的]明确青海省湟水流域地质灾害空间分布特征与规律,为该地区防灾减灾提供数据支撑与科学依据。[方法]通过小基线子集干涉测量(small baseline subset interferometric synthetic aperture radar,SBAS-InSAR)技术识别地质灾害点,结合地形因素、地质因素、环境因素、气象因素、人类活动因素进行灾害空间分布规律分析,建立逻辑回归(logistic regression,LR)—频率比(frequency response,FR)模型并检验,利用返回概率值进行易发性评价。[结果]①湟水流域所分布的潜在地质灾害以滑坡、崩塌为主,多种类型潜在地质灾害并生。滑坡与不稳定斜坡通常发育于坡度较缓的山坡上,通常伴有大量张拉与剪切裂缝,尤其在雨季发育明显,对山体下方交通、居民安全构成威胁。发育于河谷两岸的滑坡与不稳定斜坡还可能阻塞河流,形成堰塞湖,进一步加剧灾害风险。崩塌多发育在岩石结构较为疏松或风化严重的陡峭山壁,因地质脆弱,加之降雨等自然因素刺激,易使山体土块、岩石块下落,对下方的居民区和交通线路构成威胁。②研究区2425—3650 m高程区间的地质灾害分布较多,东北向为地质灾害易发坡向;地质灾害易发性随归一化植被指数(normalized digital vegetation index,NDVI)增加而降低,随坡度、地形起伏度、日降水量增加而升高,随距断层距离增加而减少。③湟水流域高易发区及较高易发区,面积约5937.60 km 2,占研究区总面积约38.78%,主要集中在湟水流域南、北边缘地区,湟中、大通、海晏交界处,以及建筑区周边边坡上。④对评价结果进行检验,模型预测性能受试者特征曲线(receiver operating characteristic curve,ROC曲线)线下面积(area under curve,AUC)为0.787,易发区由高至低FR逐级减小,与实际灾害点的分布具有良好的一致性。⑤断层核密度为湟水流域地质灾害发育的主控因子,坡向、地形起伏度、道路核密度次之,剖面曲率对地质灾害发育影响最小。[结论]①利用SBAS-InSAR技术能有效识别湟水流域潜在地质灾害,LR-FR模型获得的易发性评价结果可靠。②湟水流域地质灾害易发区的分布具有明显的空间差异性,主要分布在海拔较高、植被覆盖率较低、降雨量较大、距离断层近的地区,断层核密度为地质灾害易发性的主控因子。③湟水流域的地质灾害具有多发性、突发性和高风险性的特点,给当地居民生活、区域经济发展及生态环境带来了严重的影响。因此,对其进行监测、预警和防治工作显得尤为重要。

基于市民热线数据的北京城市居民消防诉求时空分布特征研究

基于2021年北京市12345市民热线数据,采用空间分析方法和文本分析法,探讨了消防诉求的时空分布特征、问题类型及主要发生场所。研究结果表明:1)在时间分布上,夏秋季是消防诉求的高发期,尤其是5月和9月;2)在空间分布上,消防诉求呈现明显的集聚特征,热点区域主要集中在核心区南部,并与高—高集聚模式区域大致重合,冷点区域主要分布在城区北部的生态涵养区;3)城市居民消防诉求主要涉及可燃物/火源、消防通道、消防设施、充电桩等4类问题,居民对相关安全隐患的环境和场所认知明确。根据时空分析结果,建议在火灾多发季节和月份,相关部门加强消防巡查,重点关注住宅密集区、大型商场、餐饮等生活服务区,加快升级改造这些区域的基础设施,并鼓励多方主体参与解决问题,共同推动城市消防安全工作措施的有效实施。

基于机器学习的地质灾害风险评估研究

针对地质灾害风险评估因子系数不准确和风险区划不合理的问题,本文从地质灾害多要素多特征角度出发,提出了一种基于格网的机器学习模型地质灾害风险评估方法。首先,收集和整理温州市地质灾害资料,利用ArcGIS空间分析和属性计算功能,再引入神经网络模型进行权重因子优化和筛选,将筛选的地貌类型、地形坡度、道路建设、地质构造、土壤类型、河流分布、植被覆盖度等7个因子作为地质灾害评价因子,并得到优选后的各因子权重系数;最后,利用加权分析得出地质灾害风险因子评价图。研究结果表明,通过细分格网单元的机器学习模型自动计算评价因子和权重系数,能够提高地质灾害风险评价的合理性,可以为区域性地质灾害的防灾减灾管理提供科学依据和参考。

福建省前后汛期极端降水危险性的空间差异

受台风与季风降水的不同影响,我国东南沿海地区前后汛期极端降水差异显著。为揭示该区域前后汛期极端降水危险性的差异,以福建省为典型区,应用熵权-CRITIC组合权重模型赋权的TOPSIS方法,选取最大1 d降水量、最大连续5d降水量、降水强度、暴雨时间和强降水量等5项代表性指标,分别对25个气象站点1960—2020年的前后汛期极端降水危险性进行评价。结果表明:1)福建省前汛期极端降水危险性指数总体较高,呈现自东部沿海向西北山区递增的趋势;后汛期极端降水危险性总体较低,呈现自东部沿海向西北山区递减的趋势;2)福建省前后汛期极端降水危险性指数差异大,可分为前汛期显著型站点14个、前后汛期相当型站点6个和后汛期显著型站点5个。因此,区分前后汛期并分别进行极端降水危险性评价,能够更合理地揭示区域极端降水危险性及其空间变化的规律,为区域防汛抗涝、水土保持等工作提供科技支撑。

村庄空间形态结构与地震及次生地质灾害影响因子的关联性研究——以鲁甸县龙头山镇为例

为促进村庄更好选址布局与建设,该文运用GIS技术、分形几何学、空间句法等方法,研究了鲁甸县龙头山镇村庄空间形态结构与地震及次生地质灾害影响因子的关联性。结果表明:①村庄所处岩层越硬越厚、地势越平坦、距公路越近、距最近居民点越远的区域,村庄建设受限越小村庄形态越复杂。②村庄所处距震中越近、岩层越软越薄、地势越陡峭崎岖、受邻村居民影响越大的区域,村庄紧凑度越高。③村庄建筑长轴方向平行于地震断裂带的数量相对较多,人们利用建筑刚度较大的长轴方向来应对地震产生的较大能量,从而减轻建筑受损程度。④村庄距最近一次地震震中越近、岩层越软越薄、地势越陡峭崎岖、距公路越近,其地质灾害隐患点越多,村庄道路越曲折越复杂。

基于GIS技术的巴东新城区滑坡灾害危险性区划

基于ArcGIS8软件平台开发了三峡库区巴东县新城区滑坡灾害信息系统,通过全面分析巴东新城区滑坡灾害的地形条件,工程地质岩组、构造与斜坡结构类型、人类工程活动、水的作用等影响因素,建立了相应的滑坡灾害危险性评价指标体系。采用基于GIS技术的信息量模型和敏感性评价方法,实现了巴东县新城区滑坡灾害危险性区划,其中,高危险区面积3.30km2,占7.1%;中危险区面积5.77km2,占12.4%;低危险区面积16.40km2,占35.3%;基本安全面积21.05km2,占45.2%,可以作为巴东新城区城镇建设规划和减灾防灾的参考依据。

广东省风暴潮时空分布特征及重点城市风暴潮风险研究

收集、整理、分析1949年以来广东省10个典型验潮站的近500站次台风风暴潮过程,开展了广东省台风风暴潮和超警戒风暴潮时空分布特征研究。结果表明:广东省台风风暴潮主要发生时间为7—9月,其中7月最多、9月次之,雷州半岛东岸无论发生次数还是强度都明显偏多、偏强,其次为阳江;风暴潮灾害则主要发生在7—10月,以7月最多;风暴潮灾害频发区依次为珠江口、雷州半岛东岸、阳江和汕头,风暴潮灾害严重区依次为汕头、阳江和雷州半岛东岸,阳江和雷州半岛东岸为风暴潮灾害频发区和严重区。选取受台风风暴潮影响频繁和严重的典型区域阳江市。利用业务化的台风风暴潮模式开展了不同等级台风影响下阳江市的最大风暴潮风险研究,中心最低气压为970hPa的台风在最有利路径下产生的风暴潮为185cm,约20a一遇,940hPa的台风产生的风暴潮为310cm,约为500a一遇。

台风暴雨型地质灾害时空特征及预警效果分析

在我国东南沿海山地丘陵区,台风暴雨常诱发大量山体滑坡、崩塌和泥石流地质灾害,造成财产严重损失和人员伤亡。以2015年登陆的“苏罗迪”台风为例,在系统分析“苏罗迪”台风诱发地质灾害时空分布和预警效果的基础上,得出了如下结论：（1）“苏罗迪”台风诱发的600余处崩滑流灾害,主要集中分布在浙江、福建等东南沿海地区,灾害规模以小型为主,滑坡、崩塌、泥石流数量比例约为6∶2∶1,具有空间集中群发性;台风降雨诱发地质灾害具有“即雨即滑”的特点,当日降雨当日崩滑,具有强降雨当日即发性;小时降雨空间分布不均匀,地质灾害发生时间往往比平均小时大雨强滞后,滞后时间约1～2h,具有大雨强小时滞后性。因此,台风降雨诱发地质灾害具有空间集中群发性、强降雨当日即发性、大雨强小时滞后性三大特征。（2）提出了基于“命中率、漏报率和空报率”三指标的地质灾害预警校验方法,建立完善了各指标的测算方法和计算公式。“苏罗迪”台风地质灾害预警校验结果显示,本次过程中地质灾害气象预警效果总体较好,保证了较高的命中率,较低的漏报率,但预警区空报率偏高。除地质灾害气象预警本身的技术难度外,降雨预报准确率偏低特别是极端降雨预报不足的现状也是造成地质灾害空报率偏高的原因之一。