Hazard analysis system of urban post-earthquake fire based on GIS

IntroductionPost-earthquake fire is described as the fire caused by earthquake directly or indirectly. Among the post-earthquake disasters or seismically secondary disasters, post-earthquake fire is usually the most dangerous. Experiences from historic earthquakes indicate that seismically secondary disasters may cause more severe damages and threaten our society seriously than the earthquake itself. To relieve the post-earthquake fire and minimize the economic loss, it is necessary to set up …     

Spatial modelling of rainfall trends using satellite datasets and geographic information system

This study developed a standard methodology for identifying spatial trends using satellite-based raster datasets. It involves the novelty of exploring the capabilities of a geographic information system in implementing the procedures of three trend tests, the Spearman rank order correlation (SROC) test, the Kendall rank correlation (KRC) test and the Mann-Kendall (MK) test, on raster datasets of the Tropical Rainfall Measuring Mission at 0.25° × 0.25° resolution. Comparative evaluation of the three tests revealed fair agreement of a major part of the test results for pre-, post- and non-monsoon and one-day maximum rainfall. Also, similar results from KRC and MK tests were obtained over a considerable area for annual, monsoon and monthly maximum rainfall. These findings suggest the importance of selecting the appropriate test depending on rainfall magnitudes at the chosen time scale and emphasize the robustness of the KRC and MK tests.     

基于经验统计方法的桥梁震害预测辅助决策系统

选择场地、结构、地震动和抗震设防4大类18个因素作为考虑因素，以国内外桥梁震害预测经验统计方法为主体构成了知识库，开发了与GIS结合的桥梁震害预测辅助决策系统BSVAS。该系统可初步用于大中城市防震减灾桥梁震害预测工作，并为基于GIS的防震减灾管理系统的更新提供可能。     

Modelling road surface sediment production using a vector geographic information system

Field investigations indicate that unpaved roads are the largest sediment source on St John, US Virgin Islands. Cross-sectional measurements of eroded road surfaces were used to establish an empirical relationship to predict annual road surface erosion as a function of road gradient and contributing drainage area. A model (ROADMOD) for estimating and mapping average annual sediment production from a road network was developed by combining this empirical relationship with a series of network algorithms to analyse road data stored in a vector geographic information system. ROADMOD was used to estimate road surface erosion in two St John catchments with very different road densities but similar land cover, topography and soils. Unpaved roads were found to increase sediment production in the more densely roaded catchment by a factor of three to eight, and in the less-roaded catchment by a factor of 1·3–2·0. Turbidity measurements in the receiving bays of these two catchments are consistent with model predictions and observed sediment delivery processes. Although this model was developed specifically for St John, it can easily be adapted to other locations by substituting a locally derived predictive equation for road erosion. Model assumptions, limitations and potential improvements are discussed. © 1998 John Wiley & Sons, Ltd.     

地震应急对策决策支持软件的设计与开发

基于空间决策支持技术,设计与开发了地震应急对策软件,在软件的总体设计、功能模块、数据库建设、地震应急对策模型及接口设计与模块集成等方面进行了研究与开发,并在“青岛市地震应急指挥决策支持软件系统”中得到实际应用和检验。实践证明,该软件能够实现城市地震灾害信息的科学管理,智能制定各种地震应急对策和生动的可视化,从而有效提高地震应急的效率和响应速度,为城市地震应急工作提供了有效的辅助决策手段;建成的“青岛市地震应急对策系统”对全国大中城市地震应急指挥技术系统的建设具有示范意义。     

Conceptualization of runoff processes using a geographical information system and tracers in a nested mesoscale catchment

Tracer investigations were combined with a geographical information system (GIS) analysis of the 31 km² Girnock catchment (Cairngorm Mountains, Scotland) in order to understand hydrological functioning by identifying dominant runoff sources and estimating mean residence times. The catchment has a complex geology, soil cover and topography. Gran alkalinity was used to demonstrate that catchment geology has a dominant influence on baseflow chemistry, but flow paths originating in acidic horizons in the upper soil profiles controlled stormflow alkalinity. Chemically based hydrograph separations at the catchment scale indicated that ～30% of annual runoff was derived from groundwater sources. Similar contributions (23–36%) were estimated for virtually all major sub‐basins. δ¹⁸O of precipitation (mean: ? 9·4‰; range: ? 16·1 to ? 5·0‰) and stream waters (mean: ? 9·1‰; range: ? 11·6 to ? 7·4‰) were used to assess mean catchment and sub‐basin residence times, which were in the order ～4–6 months. GIS analysis showed that these tracer‐based diagnostic features of catchment functioning were consistent with the landscape organization of the catchment. Soil and HOST (Hydrology of Soil Type) maps indicated that the catchment and individual sub‐basins were dominated by hydrologically responsive soils, such as peats (Histosol), peaty gleys (Histic Gleysols) and rankers (Umbric Leptosols and Histosols). Soil cover (in combination with a topographic index) predicted extensive areas of saturation that probably expand during hydrological events, thus providing a high degree of hydrological connectivity between catchment hillslopes and stream channel network. This was validated by aerial photographic interpretation and groundtruthing. These characteristics of hydrological functioning (i.e. dominance of responsive hydrological pathways and short residence times) dictate that the catchment is sensitive to land use change impacts on the quality and quantity of streamflows. It is suggested that such conceptualization of hydrological functioning using tracer‐validated GIS analysis can play an important role in the sustainable management of river basins. Copyright © 2006 John Wiley & Sons, Ltd.     

Application of the geographical information systems approach to watershed mass balance studies

This study was undertaken to test the utility of a geographical information systems (GIS) approach to problems of watershed mass balance. This approach proved most useful in exploring the effects that watershed scale, lithology and land use have on chemical weathering rates, and in assessing whether mass balance calculations could be applied to large multilithological watersheds. Water quality data from 52 stations were retrieved from STORET and a complete GIS database consisting of the watershed divide, lithology and land use was compiled for each station. Water quality data were also obtained from 7 experimental watersheds to develop a methodology to estimate annual fluxes from incomplete data sets. The methodology consists of preparing a composite of daily flux data, calculating a best fit sinusoid and integrating the equation to obtain an annual flux. Comparison with annual fluxes calculated from high resolution data sets suggests that this method predicts fluxes within about 10% of the true annual flux. Annual magnesium fluxes (moles km⁻² yr⁻¹) were calculated for all stations and adjusted for fluxes from atmospheric deposition. Magnesium flux was found to be a strong function of the amount of carbonate in the watershed, and silica fluxes were found to increase with the fraction of sandstone present in the watershed. All fluxes were strongly influenced by mining practices, with magnesium fluxes from affected watersheds being 6–10 times higher than fluxes from comparable pristine watersheds. Mining practices enhance chemical weathering by increasing the surface area of unweathered rock to which water has access and by increasing acidity and rate of mineral weathering. Fluxes were also found to increase with watershed size. This scale dependence is most likely caused by the sensitivity of weathering fluxes to even minor quantities of carbonates, which are likely to be found in all lithologies at larger scales. Mass balances were carried out in watersheds where gauged sub-watersheds made up more than 95% of the area. The calculations show large magnesium flux and water balance discrepancies. These errors may be a result of significant groundwater inputs to streams between gauges. The results suggest that improvements in how we measure discharge and estimate fluxes may be required before we can apply mass balance techniques to larger scales. © 1997 John Wiley & Sons, Ltd.     

Modelling flood-prone area and vulnerability using integration of multi-criteria analysis and HAND model in the Ogun River Basin,Nigeria

ABSTRACT

In this study, a GIS-based integration of multi-criteria analysis and the Height Above Nearest Drainage (HAND) terrain model was adopted to delineate potential flood hazard zones and vulnerability of the Ogun River Basin, Nigeria. Flood causative factors were used as input for multi-criteria analysis using an analytical hierarchy process (AHP) and weighted overlay in ArcGIS 10.5 to generate potential flood hazard zones. The flood hazard map was overlaid with demographic population data to identify areas where vulnerable people and assets are located. The results show the varying degree of people’s susceptibility to flood hazards. Flood hazard zones were classified into Very High, High, Moderate, Low and Very Low, with area coverage of 1269.40, 14139.50, 7188.40, 17.41 and 0.85 km², respectively (occupied by 466 290, 355 542, 69 554, 231 and 54 people, respectively). This study serves as a preliminary guide for early warning and policy decision-making for flood disaster risk reduction.     

大庆油田防震减灾信息管理系统建设

近年来，GIS技术被广泛地应用于城市或区域的防震减灾信息管理系统的建设。本文着重论述了大庆油田有限责任公司防震减灾信息管理系统的建设，以及建成后的系统所包含的主要内容和所能实现的功能。应用GIS技术建设大型企业防震减灾系统是一个新的尝试，所完成的系统不但能对企业在地震应急中起到辅助决策作用，而且对于日常管理也是十分方便的。该系统的运行为大型企业防灾系统的建设提供了思路和借鉴。     

Characterization of groundwater quality in Kinmen Island using multivariate analysis and geochemical modelling

Kinmen is located in the south‐west of Mainland China and mainly has two islands, Large Kinmen and Leiyu. Residents in Kinmen have drunk groundwater over several decades. This work characterized the quality of groundwater in Kinmen using factor analysis (FA), cluster analysis (CA) and geochemical simulation. The factor scores were plotted spatially to illustrate the groundwater quality and were used to discuss the grouped relationship using CA. Salinization, redox and organic matter factors are identified from 17 hydrochemical measurements in 18 wells. Acidic and oxidizing groundwater with nitrate‐N pollution is distributed mainly in the west of Large Kinmen. Saline groundwater is distributed to the north‐east of Large Kinmen and in the south of Leiyu. Groundwater with organic matter is present throughout Leiyu. Five groups of the groundwater quality divided by CA can be interpreted according to one to three factors. The grouped characteristics of the groundwater quality help the local government and industries to plan the use and protection of groundwater resources. Furthermore, a geochemical simulation was used to demonstrate the formation processes of the acidic and oxidizing groundwater properties in granitic sediments. A large amount of the precipitation of the kaolinite and magnetite releases concentrations of hydrogen ion and raises the redox potential in the aquifers. Copyright © 2007 John Wiley & Sons, Ltd.     

GIS-based emergency response system for sudden water pollution accidents

The frequent occurrence of sudden water pollution accidents brings enormous risks to water environment safety. Therefore, there is great need for the modeling and development of early warning systems and rapid response procedures for current water pollution situation in China. This paper proposes an emergency response system based on the integration of Geographic Information System (GIS) technology and a hydraulic/water-quality model. Using the spatial analysis and three-dimensional visualization capabilities of GIS technology, we calculated pollutant diffusion measures, and visualized and analyzed the simulation results, in order to provide the services of early warning and emergency response for sudden water pollution accidents in the Xiangjia Dam area on the Yangtze River. The results show that the proposed system offers reliable technological support for emergency response to sudden water pollution events, and it shows good potential for wide applications in various aspects of water resources protection.     

A spatiotemporal probabilistic modelling of storm‐induced shallow landsliding using aerial photographs and logistic regression

Landslides constitute one of the major natural hazards that could cause significant losses of life and property. Mapping or delineating areas prone to landsliding is therefore essential for land‐use activities and management decision making in hilly or mountainous regions. A landslide hazard map can be constructed by a qualitative combination of maps of site conditions, including geology, topography and geomorphology, by statistical methods through correlating landslide occurrence with geologic and geomorphic factors, or by using safety factors from stability analysis. A landslide hazard map should provide information on both the spatial and temporal probabilities of landsliding in a certain area. However, most previous studies have focused on susceptibility mapping, rather than on hazard mapping in a spatiotemporal context. This study aims at developing a predictive model, based on both quasi‐static and dynamic variables, to determine the probability of landsliding in terms of space and time. The study area selected is about 13 km² in North Lantau, Hong Kong. The source areas of the landslides caused by the rainstorms of 18 July 1992 and 4–5 November 1993 were interpreted from multi‐temporal aerial photographs. Landslide data, lithology, digital elevation model data, land cover, and rainfall data were digitized into a geographic information system database. A logistic regression model was developed using lithology, slope gradient, slope aspect, elevation, slope shape, land cover, and rolling 24 h rainfall as independent variables, since the dependent variable could be expressed in a dichotomous way. This model achieved an overall accuracy of 87·2%, with 89·5% of landslide grid cells correctly classified and found to be performing satisfactorily. The model was then applied to rainfalls of a variety of periods of return, to predict the probability of landsliding on natural slopes in space and time. It is observed that the modelling techniques described here are useful for predicting the spatiotemporal probability of landsliding and can be used by land‐use planners to develop effective management strategies. Copyright © 2003 John Wiley & Sons, Ltd.     

基于GIS的抗震设计地震动查询系统

基于ArcView CIS软件开发平台，建立了设计地震动参数和最不利设计地震动数据库，建成了基于性态设计和考虑最不利设计地震动因素的设计地震动查询系统，该系统主要为基于PC机工作的结构抗震设计人员提供相应的设计地震动参数和最不利设计地震动的设计地震动信息查询服务。     

基于ArcView9.0的城市震害预测及应急对策信息系统研究

介绍了城市防震减灾信息系统基本的构成及功能,并针对国内研发中存在的不足从四个方面进行了完善,即增加了地震预警级别判定功能,丰富了地震信息的录入方式,改进了城市群体建筑物震害预测的计算模型,引入了应急对策模块并利用G IS的可视化功能加以表现。在此基础上研发了基于ArcV iew9.0的城市震害预测及应急对策信息系统,并以山西运城市城区的实际数据进行了系统演示。     

基于GIS的城市地质环境敏感性评价--以兰州市为例

城市地质环境敏感性评价是城市可持续发展所要求的科学规划的基础．本文以兰州市为例，利用地理信息系统建立城市地质环境基础数据库．系统选取评价指标体系，采用专家赋值和层次分析法构建评价模型．结果表明基于GIS的评价模型可高效准确地进行城市地质环境敏感性评价．     

Stack unit mapping of coastal aquifer to predict and control sea water intrusion using remote sensing and a geographical information system

Aquifers are inherently susceptible to contamination and coastal aquifers in specific are highly vulnerable to sea water intrusion. For efficient planning and management of coastal aquifers in Kayalpattu and Tiruchopuram villages, which extend over 4·05 km², it is essential to delineate and predict the extent of intrusion into the shallow aquifer. Management of ground water in coastal aquifers is composed of major elements that should be properly evaluated, and special attention is given to the sea water intrusion problem. Different data, like hydro‐geomorphological and depth‐wise iso‐apparent resistivity, are integrated spatially using a geographical information system. The stack‐unit mapping approach is used to delineate the zones with iso‐apparent resistivity of less than 10 Ω m have been found to be increasing in areal extent with reference to depth. Copyright © 2003 John Wiley & Sons, Ltd.     

Sensitivity analysis in groundwater vulnerability assessment based on GIS in the Mahdia-Ksour Essaf aquifer,Tunisia: a validation study

Abstract

The assessment of groundwater vulnerability to pollution has proved to be an effective tool for water resource management, especially in arid and semi-arid regions like Mahdia and Ksour Essaf. The main objective of this study is to assess the aquifer vulnerability by applying the DRASTIC method as well as using sensitivity analysis to evaluate the effect of each DRASTIC parameter on the final vulnerability map. An additional objective is to demonstrate the role of the GIS techniques in the vulnerability assessment. The DRASTIC method assigns a high vulnerability to the coast of the Mahdia-Ksour Essaf. The lowest values are observed in the southern part of the study area. A sensitivity analysis applied in this study suggests that net recharge, aquifer media and depth of groundwater are the key factors determining vulnerability. The model is validated with groundwater quality data and the results have shown strong relationships between modified DRASTIC Vulnerability Index and nitrate and chloride concentrations.

Citation Saidi, S., Bouri, S. & Ben Dhia, H. (2011) Sensitivity analysis in groundwater vulnerability assessment based on GIS in the Mahdia-Ksour Essaf aquifer, Tunisia: a validation study. Hydrol. Sci. J. 56(2), 288–304.     

Characterizing rainfall–groundwater dynamics in a hard‐rock aquifer system using time series,geographic information system and geostatistical modelling

The aim of this study was to investigate rainfall–groundwater dynamics over space and annual time scales in a hard‐rock aquifer system of India by employing time series, geographic information system and geostatistical modelling techniques. Trends in 43‐year (1965–2007) annual rainfall time series of ten rainfall stations and 16‐year (1991–2006) pre‐monsoon and post‐monsoon groundwater levels of 140 sites were identified by using Mann–Kendall, Spearman rank order correlation and Kendall rank correlation tests. Trends were quantified by Kendall slope method. Furthermore, the study involves novelty of examining homogeneity of pre‐monsoon and post‐monsoon groundwater levels, for the first time, by applying seven tests. Regression analysis between rainfall and post‐monsoon groundwater levels was performed. The pre‐monsoon and post‐monsoon groundwater levels for four periods – 1991–1994, 1995–1998, 1999–2002 and 2003–2006 – were subjected to geographic information system‐based geostatistical modelling. The rainfall showed considerable spatiotemporal variations, with a declining trend at the Mavli rainfall station (p‐value < 0.05). The Levene's tests revealed spatial homogeneity of rainfall at α = 0.05. Regression analyses indicated significant relationships (r² > 0.5) between groundwater level and rainfall for eight rainfall stations. Non‐homogeneity and declining trends in the groundwater level, attributed to anthropogenic and hydrologic factors, were found at 5–61 more sites in pre‐monsoon compared with post‐monsoon season. The groundwater declining rates in phyllite–schist, gneiss, schist and granite formations were found to be 0.18, 0.26, 0.21 and 0.14 m year^?1 and 0.13, 0.19, 0.16 and 0.02 m year^?1 during the pre‐monsoon and post‐monsoon seasons, respectively. The geostatistical analyses for four time periods revealed linkages between the rainfall and groundwater levels. Copyright © 2013 John Wiley & Sons, Ltd.     

Macrobenthos habitat mapping in a tidal flat using remotely sensed data and a GIS-based probabilistic model

This paper proposes and tests a method of producing macrofauna habitat potential maps based on a weights-of-evidence model (a probabilistic approach) for the Hwangdo tidal flat, Korea. Samples of macrobenthos were collected during field work, and we considered five mollusca species for habitat mapping. A weights-of-evidence model was used to calculate the relative weights of 10 control factors that affect the macrobenthos habitat. The control factors were compiled as a spatial database from remotely sensed data combined with GIS analysis. The relative weight of each factor was integrated as a species potential index (SPI), which produced habitat potential maps. The maps were compared with the surveyed habitat locations, revealing a strong correlation between the potential maps and species locations. The combination of a GIS-based weights-of-evidence model and remote sensing techniques is an effective method in determining areas of macrobenthos habitat potential in a tidal flat setting.     

Introducing the recharge–discharge relationship to evaluate the recharge coefficient of karstic aquifers: thematic and indexing approaches

ABSTRACT

Karst aquifers and springs are important with respect to their potential for supplying drinking water in regions suffering from water scarcity in Iran. Accordingly, it is essential to determine the recharge potential of the catchment and the regions with higher obtainability potential. This study provides a road map for the Sheshpeer catchment in southern Iran. A recharge potential (RP) map was produced from which a recharge index (RI) was computed for several selected springs in the catchment. Furthermore, the unit discharge (q) – defined as the average annual discharge for a given catchment area and unit rainfall depth for each spring – was calculated. The plot of q versus RI for the springs showed a linear positive relationship between the two variables (R ² = 0.9). Applying the trend equation of this plot to the whole Sheshpeer karstic catchment reveals that its long-term recharge coefficient is 0.74.