Risk analysis for drought hazard in China: a case study in Huaibei Plain

In recent decades, risk management is significant to mitigate the severe status caused by droughts. As one of the primary components in risk analysis, drought hazard analysis is basic but important. In this paper, the framework of drought risk analysis and the methodology for drought hazard analysis are presented, and Huaibei Plain of China is chosen as the study area. The whole study region is divided into three parts (northern, central, and southern) by geographical factors, and a developed index named drought comprehensive Z index (DCZI) containing hydrological and meteorological factors is employed for drought hazard analysis in each area. By comparison, it implicates that DCZI is applicable for Huaibei Plain and indicates drought extent more objectively. Moreover, the results of drought hazard analysis reflect that the northern area is affected by droughts more seriously. As for the whole region, there is a great probability of severe drought. Finally, some policy recommendations on drought management are also made.     

突发性地质灾害气象预警预报研究综述

分析了国内外突发性地质灾害气象预警预报相关研究动态,对地质灾害气象预警预报的研究现状和研究进展作了系统地总结.根据最新研究成果,从预警预报理论方法等方面对地质灾害预警预报的发展趋势进行了初步预测,并结合地质灾害气象预警预报的经验,就地质气象灾害预警预报存在的问题提出一些问题和看法.     

公路建设用地地质灾害危险性评估实践与认识——以湖北襄-十高速公路襄武段为例

文章以湖北省襄-十高速公路襄樊至武当山段为例，提出了建设用地地质灾害危险性评估范围、评估重点的确定方法，就地质灾害危险性的涵义展开讨论并给出了明确定义。结合工程实践，对现状评估、预测评估与综合评估的要点、方法展开论述，提出高速公路地质灾害危险性等级划分标准，同时提出以防灾工程投入比大小评估建设用地土地适宜性的量化指标，并对存在的主要问题提出相应建议。     

泰安市地质灾害预警预报系统研究

主要介绍了泰安市地质灾害气象风险预警与指挥系统。系统开发的主要目的是为了更好的与泰安市地质灾害防治工作相结合,通过对气象因素及地质灾害资料的分析和研究,基于地质灾害气象预警模型,采用先进的 GIS 技术能实现对地质灾害易发风险性区域预警,能直观地了解到各部分区域的地质灾害易发风险性,为各级政府防灾减灾提供科学的技术支撑。     

Seismic-event-based methodology to obtain earthquake-induced translational landslide regional hazard maps

A seismic-event-based methodology to generate earthquake-induced translational landslide maps using Newmark method is proposed. The steps are: (1) to construct a GIS-based geotechnical database; (2) to identify those areas that are susceptible to the occurrence of translational landslides based on available geological information; (3) to compute a static safety factor; (4) to compute the critical acceleration that defines the threshold acceleration required to cause a displacement; (5) to characterize the seismic hazard as a set of stochastic events, collectively exhaustive and mutually exclusive, that fully describes the hazard spatial distribution and annual frequency of occurrence (in accordance with the earthquake location, depth and magnitude) with the appropriate ground-motion prediction equations; (6) to compute the Newmark displacement; and finally, (7) to carry out a probabilistic translational landslide hazard analysis to estimate an exceedance rate of a given displacement. This methodology is applied to Mexico, and maps for return periods of 150 and 500 years are presented. Results shown in maps are estimations of where translational landslides may occur and should be useful to carry out local studies to elaborate recommendations of site specific hazard reduction plans as well as to calculate insurance rates. In addition, these results are useful to identify civil protection actions, risk management at regional and local level, and land use planning, as well as for promoting more detailed vulnerability and risk studies at different scales.     

Suitability evaluation of rural residential areas under the threat of geological disasters:A case study in Yinchanggou watershed of Pengzhou City

At present, the research on the layout of rural residential areas in the mountainous environment under the threat of earthquake disasters and frequent geological disasters is still rare. Taking Yinchanggou watershed in Longmenshan Town of Pengzhou City as an example, based on the summary of the geological hazard development characteristics in this area, the authors carried out the hazard risk zoning through 8 indexes. Then the geological hazard risk zoning was used as the primary factor to evaluate the suitability of rural residential areas. Besides, combined with the topographical conditions, socio-economic situation and ecological environment, a suitable evaluation index system for rural residential land under the threat of geological disasters was constructed, with the restrictive conditions of extremely high-risk areas, single geological hazards, slopes ≥25° and basic farmland protection areas. Finally, the fuzzy comprehensive evaluation method was used to evaluate the suitability of residential land in Yinchanggou watershed of Pengzhou City. The results show that high suitability areas account for 4.2% of the total area of the study area, moderate suitability areas 11.4%, low suitability areas 10.5%, and unsuitable areas 73.8%. The “suitable” areas for rural residential land are mainly distributed along the highway, and some are multiple “blocky” concentrated distribution areas. The terrain is flat and the traffic condition is convenient, which can provide some guidance for the selection of new rural residential locations.     

地质灾害威胁下的农村居民点用地适宜性评价——以彭州市银厂沟流域为例

目前针对受震灾威胁、地质灾害频发的山地环境下的农村居民点布局研究尚不多见。该文以彭州市龙门山镇银厂沟流域为例,首先在总结分析区内地质灾害发育特征的基础上,基于8项指标进行地质灾害危险性分区; 然后,将地质灾害危险性区划结果作为影响农村居民点用地适宜性评价的首要因素,再结合地形条件、社会经济和生态环境等方面,以地质灾害极高危险区、单体地质灾害危害范围、坡度≥25°和基本农田保护区为限制性条件,构建地质灾害威胁下的农村居民点用地适宜性评价指标体系; 最后,采用模糊综合评价法对彭州市银厂沟流域内居民点用地适宜性进行评价分级。研究结果表明: 高度适宜区占研究区总面积的4.2%,中度适宜区占11.4%,低度适宜区占10.5%,不适宜区占73.8%; 农村居民点用地“适宜”区域主要沿公路分布,并存在多个“块状”集中分布区,这些地区地形平坦,交通条件便利,可为新农村住宅位置的选择提供指导意见。     

基于地震动信号分析的地质灾害过程重构方法研究与应用

地质灾害启动及演进过程中对途经的村庄、植被、基础设施等均会造成不同程度的破坏,而深入研究灾害的演进过程有助于灾害预警和防治工作,能减少灾区人员伤亡、降低经济损失。然而由于地质灾害的强破坏性和突发性,使得现场的监测仪器和设备易受灾害的影响,甚至被破坏,导致难以完整且准确地监测到灾害过程,这限制了对地质灾害过程的深入研究,因此亟需一种新的方法来进行灾害过程的重构。随着科技的发展,现有高精度地震仪能够记录伴随地质灾害而产生的地震动信号,并且已有不少研究者进行了基于地震动信号的灾害分析研究。基于现有研究的基础,本文提出一套基于地震动信号的地质灾害重构研究思路和方法体系:通过运用带通滤波器(BP-filter)、经验模态分解(EMD)、快速傅里叶变换(FFT)、短时傅里叶变换(STFT)、功率谱密度计算(PSD)等方法对灾害过程产生的地震动信号进行处理和分析,然后结合灾害现场调查结果进行对比分析以反演灾害的基本特征,进而与数值模拟结果进行耦合,最终实现灾害过程的重构。本文基于地震动信号对堰塞湖、滑坡、泥石流等不同灾种进行案例研究与分析,旨在为地质灾害演进过程的研究提供一种新的研究思路和方法体系。     

水利水电工程中地质灾害预防与地质环境保护对策探讨

水利水电工程是一项系统工程,涉及面广,影响范围大,地质灾害与地质环境及工程建设活动密切相关,既相互依存,相互作用,又相互影响,地质灾害类型相对较多,对工程的影响也各不相同。加强地质灾害的预防对促进水利水电工程建设健康协调发展具有重要而深远的意义。本文在对水利水电工程地质灾害进行成因分析的基础上,对地质灾害综合预防与地质环境保护措施进行探讨。     

Landslide susceptibility and hazard assessment in San Ramón Ravine, Santiago de Chile, from an engineering geological approach

Debris flows and soil and rock slides are among the main geological hazards in the mountain foothills of Central Chile. Geological risk associated with the development of landslides, especially debris flows triggered in the basins of ravines that drain into the capital city, Santiago, has increased in time due to accelerated urban expansion. A landslide hazard evaluation in the San Ramón Ravine, located within the foothills of Santiago is presented. Hazard evaluation is based on a methodology that combines the determination of landslide susceptibility calculated by integration of conditioning factors, with the assessment of slope failure and runout probabilities incorporating geotechnical engineering approaches. The methodology is appropriate for medium or subregional scale studies with limited data. The results show that in San Ramón Ravine the landslide hazard consists mainly of debris flows, rock block slides, rock falls and shallow soil slides. Among these, debris flows are the most important due to the urban area that can be affected. Other case studies show that the method can be used in other regions with minor adaptations for territorial planning or for engineering and environmental purposes.     

A composite index for drought hazard assessment using CPC rainfall time series data

Hazard analysis is the first step in any disaster management activity. Drought is a serious environmental hazard strongly limiting the agricultural production in the tropical countries like India. A comprehensive drought hazard map is useful for multiple perspectives such as agriculture, environment and hydrology. In this study, daily rainfall data of the Climate Prediction Centre during the south-west monsoon season (June–September) of 12 years, over India was analysed. Based on rainfall and rainy days, six indicators of drought were generated which were then synthesized into a composite index of drought hazard for every 10 × 10 km pixel. The weights for the composite index were generated through variance approach. The index has effectively captured the spatial variations in meteorological drought across India by showing a typical pattern with increasing hazardous area from east to west. The drought hazard map also shows considerable agreement with the climate classification map and the drought proneness map reported by other studies. Thus, the current study presents a simple and novel approach for drought hazard analysis, using the routinely available geospatial rainfall data products. The methodology can be extended to other geographies and disasters too. Use of time series data of longer period would improve the reliability of the composite drought hazard index.     

A Hazard Assessment Method for Potential Earthquake-Induced Landslides – A Case Study in Huaxian County, Shaanxi Province

The hazard assessment of potential earthquake-induced landslides is an important aspect of the study of earthquake-induced landslides. In this study, we assessed the hazard of potential earthquake-induced landslides in Huaxian County with a new hazard assessment method. This method is based on probabilistic seismic hazard analysis and the Newmark cumulative displacement assessment model. The model considers a comprehensive suite of information, including the seismic activities and engineering geological conditions in the study area, and simulates the uncertainty of the intensity parameters of the engineering geological rock groups using the Monte Carlo method. Unlike previous assessment studies on ground motions with a given exceedance probability level, the hazard of earthquake-induced landslides obtained by the method presented in this study allows for the possibility of earthquake-induced landslides in different parts of the study area in the future. The assessment of the hazard of earthquake-induced landslides in this study showed good agreement with the historical distribution of earthquake-induced landslides. This indicates that the assessment properly reflects the macroscopic rules for the development of earthquake-induced landslides in the study area, and can provide a reference framework for the management of the risk of earthquake-induced landslides and land planning.     

岩溶地区合理开发资源与防治地质灾害

在地球上,自然灾害间存在着关系链,包括气候灾害与地质灾害间关系链,地质灾害与生物灾害间关系链,以及地质灾害间的关系链,不合理开发所有资源,都会诱发灾害,因此,讨论合理开发资源并防止诱发地质灾害问题,是非常重要的。     

A quantitative model to evaluate mine geological environment and a new information system for the mining area in Jilin province,mid-northeastern China

The reliability of mine geological environment quality assessment highly depends on a large amount of survey data, a comprehensive evaluation system and an effective evaluation model. Using computer technology to integrate large amount of data can help to ensure the valid management and the effective assessment. Compared with previous studies, this study has improved and enriched the evaluation system and optimized the traditional evaluation method. Moreover, combining geology with computer science, it has developed the evaluation function of mine geological environment and realized the intersection and innovation of the discipline. The specific research content has the following three parts. First, a new design for an evaluation system which can synthetically describe the mine geological environment is presented. Second, a particle swarm optimization (PSO)-support vector machine (SVM) model is established as an alternative to traditional approaches that avoid interference from artificial factors. Third, a new mine geological environmental information system (MGEIS) is presented to efficiently manage data. Then, PSO-SVM evaluation model is embedded in it, and the mine geological environment in Jilin province is assessed by using MGEIS. Decisions can be presented based on the evaluation results in this study to better support the recovery of the local mine geological environment.     

Analysis of drought hazards in North China: distribution and interpretation

This paper examines the characteristics of historical meteorological hazards and associated natural-anthropogenic variations in China, with specific attention given to the meteorological drought hazards occurring at very high frequency and affecting social?Ceconomic development in North China. Owing to an increasing awareness of meteorological droughts in this area, the aim of this contribution is to provide a comprehensive overview of meteorological droughts in North China by reviewing the meteorological references and their intrinsic linkages with climatic, geological, and anthropogenic controls. Our study highlights the region-wide meteorological droughts with a rather clear recurrence of 30 and 100?years, totally indicating Shanxi and Shandong being the predominated area suffering from extreme meteorological droughts. The spatial and temporal distribution of meteorological drought hazards in this region is considered to be a function of climatic, topographic, hydrological, and anthropogenic characteristics. In view of the wide distribution and linkage with geo-hazards and changes of dynasties, the meteorological drought hazard is one of the key issues for long-term social?Ceconomic harmonization. This study can be expected to prioritize drought mitigation measures and ensure regional sustainable development in North China.     

陕北能源化工基地煤炭生产可持续发展的地质与环境地质问题研究

陕北能源化工基地多种矿产富集,煤炭、石油、天然气、岩盐等矿产资源储量丰富,经过近20年的建设开发,已初步建成为中国重要的能源接续地和大型煤化工基地。但该区水资源短缺、生态环境脆弱的现状,相对资源开发增长速度较快的煤炭生产和转化来说,其环境压力巨大,暴露出的矿产地质与环境地质问题突出．已影响到基地建设的可持续发展。为此提出了如下应对措施：加强地质勘查工作,提高煤炭资源保障程度：加强多种矿产并存区的综合地质勘探、评价和规划,推进矿产资源的综合开发与利用;加强生产矿井的监督和管理,不断提高资源采收率;开展矿区水资源的勘察评价,加强水资源的规划和协调管理;深化《保水采煤技术研究》,推广实施矿井水及工业、生活污水的综合利用;建立健全防灾减灾体系建设,做好矿区地质灾害监测、评价及治理工作;加强矿区环境整治和生态保护工作;建立陕北能源化工基地煤炭资源、环境可持续发展的长效机制。     

Data concerning seismic risk evaluation in Romania

In this paper some results are presented of the researches performed in two main directions: (1) the geologic hazard assessment in the extra-Carpathian territory and (2) the estimation of the degree of exposure of the population to this hazard. For the evaluation of the geologic hazard, data regarding the seismic history of the extra-Carpathian territory (only the intermediate depth Vrancea earthquakes were analyzed) and the recent geodynamical processes which can be triggered or amplified by seismic vibrations, were used. These data published in two previous papers, have been reevaluated and are present in a unitary form, allowing for the separation into zones with different degrees of geological hazard in the analyzed territory. The data regarding the number, space distribution, and density of the population has made it possible to estimate the number of people living in each zone.Paper presented at the 21st General Assembly of the European Seismological Commission held in Sofia, 1988.     

陆地表层地质环境质量综合评价与地质灾害系统分析——以广东沿海地带为例

将广东沿海陆地表层地质环境划分为构造稳定性、坡面稳定性和地基稳定性三个评价层面 ,其中包括由 9个指标构成的评价指标体系 ;确定了各指标的权重和五级分级标准和环境质量的五级标准 ;使用模糊数学综合评价模型将广东沿海 190个评价单元划分为 2 2个地质环境质量区。在灾害基本数据库和灾害时空分布分析的基础上 ,划分了 9个地质灾害一级分区及 32个二级分区 ,确定了地质环境、气候气象和人为活动因素三大类致灾主控因子 ;构造了三种地质灾害系统的概念模型和灾害预测指标体系框架 ,建立了地质灾害地理信息系统。     

Comprehensive analysis and quantitative evaluation of the influencing factors of karst collapse in groundwater exploitation area of Shiliquan of Zaozhuang, China

Karst collapse is a type of complicated environmental and geological hazard that can be caused by many factors: natural factors, such as rainfall, and human activities, such as overpumping of groundwater. Therefore, it is important to make a comprehensive analysis and evaluation on karst collapse risks and impacts of the influencing factors of karst collapse. However, how these factors affect karst collapse is still a problem, which has not yet been well solved. Taking the karst collapse in groundwater exploitation area of Shiliquan of Zaozhuang, China, as the example, and based on the comprehensive analysis of the formation rule and mechanism of karst collapse in this area, this paper mainly employs Quantification Theory to make a quantitative analysis and evaluation of various influencing factors of karst collapse in the groundwater exploitation area of Shiliquan of Zaozhuang. It thereby determines the impact of different influencing factors on karst collapse strength, and identifies the dominant and minor factors that affect the karst collapse. It also provides some criteria for the prevention of karst collapse and protection of karst water resources and environment.     

Automated mapping of rock slope geometry,kinematics and stability with RSS-GIS

A GIS-implemented, deterministic approach for the automated spatial evaluation of geometrical and kinematical properties of rock slope terrains is presented. Based on spatially distributed directional information on planar geological fabrics and DEM-derived topographic attribute data, the internal geometry of rock slopes can be characterized on a grid cell basis. For such computations, different approaches for the analysis and regionalization of available structural directional information applicable in specific tectonic settings are demonstrated and implemented in a GIS environment. Simple kinematical testing procedures based on feasibility criteria can be conducted on a pixel basis to determine which failure mechanisms are likely to occur at particular terrain locations. In combination with hydraulic and strength data on geological discontinuities, scenario-based rock slope stability evaluations can be performed. For conceptual investigations on rock slope failure processes, a GIS-based specification tool for a 2-D distinct element code (UDEC) was designed to operate with the GIS-encoded spatially distributed rock slope data. The concepts of the proposed methodology for rock slope hazard assessments are demonstrated at three different test sites in Germany.