Antarctic surveying, mapping and remote sensing is one of the important aspects of the Chinese Antarctic geoscience research program that stretch back over 25 years, since the first Chinese National Antarctic Research...Antarctic surveying, mapping and remote sensing is one of the important aspects of the Chinese Antarctic geoscience research program that stretch back over 25 years, since the first Chinese National Antarctic Research Expedition (CHINARE) in 1984. During the 1980's, the geodetic datum, height system and absolute gravity datum were established at the Great Wall and Zhongshan Stations. Significant contributions have been made by the construction of the Chinese Great Wall, Zhongshan and Kunlun Stations in Antarctica. Geodetic control and gravity networks were established in the King George Islands, Grove Moun- tains and Dome Argus. An area of more than 200 000 km2 has been mapped using satellite image data, aerial photogrammetry and in situ data. Permanent GPS stations and tide gauges have been established at both the Great Wall and Zhongshan Stations. Studies involving plate motion, precise satellite orbit determination, the gravity field, sea level change, and various GPS applications for atmospheric studies have been carried out. Based on remote sensing techniques, studies have been undertaken on ice sheet and glacier movements, the distributions of blue ice and ice crevasses, and ice mass balance. Polar digital and visual mapping tech- niques have been introduced, and a polar survey space database has been built. The Chinese polar scientific expedition manage- ment information system and Chinese PANDA plan display platform were developed, which provides technical support for Chi- nese polar management. Finally, this paper examines prospects for future Chinese Antarctic surveying, mapping and remote sens- ing.展开更多
Average credit scores for people in the United States (US) differ from state to state. Some states have high, and some states have low average credit scores. Since lenders and employers use credit scores to make loa...Average credit scores for people in the United States (US) differ from state to state. Some states have high, and some states have low average credit scores. Since lenders and employers use credit scores to make loan and employment decisions, people living in states where average credit scores are high should experience the benefits of living where credit scores tend to allow more favorable loan and employment decisions. Although credit scores are the direct result of credit histories, credit histories may be impacted by demographic factors. If the demographic factors that impact credit histories are identified, ways to improve credit scores are likely to be discovered and available to people and state government policymakers. This study looks for demographic factors to indirectly explain the average credit scores for people living in each state of the US. The methodology includes statistical analyses and geographic information systems (GIS) mapping. Statistical analyses provide evidence to suggest that state average credit scores are explained by the demographic factors of education, family, income, and health. GIS mapping reveals clusters of states with similar demographics and credit scores.展开更多
Cadastral maps are an important component of land administration in most countries. In virtually all developed countries, the needs of computerized land and geographic information systems (LIS/GIS) has given urgent im...Cadastral maps are an important component of land administration in most countries. In virtually all developed countries, the needs of computerized land and geographic information systems (LIS/GIS) has given urgent impetus to computerizing cadastral maps and creating digital cadastral data bases (DCDB). This process is creating many institutional, legal, technical and administrative problems. This desire to establish DCDBs is being given increased impetus due to a new range of enabling technologies such as satellite position fixing (GPS), improved spatial data collection techniques such as digital theodolites and “soft copy” photogrammetry, as well as a vast range of new information and communications technological tools, thus contributing to the advancement and keeping up with the great countries. This paper presents the problem of cadastral maps. The hitherto existing cadastre, consisting of paper maps and land registers, is now becoming insufficient. Its shortcomings force developments leading to its improvement. One of the ways is the creation of a Land Information System. A digital cadastral map is the main component of this system. The structure and information content of the map is presented, its differences from analogue maps are shown, and the process of map creation is described. A digital cadastral map can be the basis for additional thematic layers, successively converting it into a complex system for management of administrative units.展开更多
Defining the spatial extent of mountain areas has long been a challenge. In the present century, the availability of digital elevation models(DEMs) incorporated into geographic information systems(GIS) has allowed the...Defining the spatial extent of mountain areas has long been a challenge. In the present century, the availability of digital elevation models(DEMs) incorporated into geographic information systems(GIS) has allowed the definition of mountain areas based on topographic and other criteria. This paper presents the various delineations of mountains that have been prepared at three scales – global, regional(Europe), and national – and explores the reasons and processes leading to these delineations, and how they have been used. A detailed case study is then presented for Norway. Overall, two types of approaches to mapping mountains have been taken: first, considering mountains per se, based on elevation and/or topography; second, considering them among other categories, e.g., landforms or biogeographical, environmental or landscape zones. All attempts to map mountain areas derive essentially from the objectives of those commissioning and/or undertaking the work; a unitary definition remains unlikely.展开更多
District Ghizer is a rugged mountainous territory which experiences several landslides each year. There are 16 major landslide areas and 53 villages that are at high risk to hazards. Keeping in view the severity of na...District Ghizer is a rugged mountainous territory which experiences several landslides each year. There are 16 major landslide areas and 53 villages that are at high risk to hazards. Keeping in view the severity of natural hazards, the present study was designed to generate landslide susceptibility map based on twelve causative factors viz., slope, aspect, elevation, drainage network, Stream Power Index (SPI), Topographic Wetness Index (TWI), lithological units, fault lines, rainfall, road network, land cover and soil texture. Soil texture was determined by particle size analysis and data for other factors were acquired from freely available sources. Analytical Hierarchy Process (AHP) was employed to identify major landslide causative factors in the district Ghizer. Further, a temporal assessment from 1999 till 2015 was generated to assess the impact of land cover change on landslides. It indicated that the barren soil/ exposed rocks and glaciers have reduced while the vegetation and water classes have shown increment. The total area that lies in moderate to very high landslide susceptible zones was 74.38%, while slope is the main landslide causative factor in the district Ghizer. Validation of the susceptibility map showed 88.1% of the landslides in the study area had occurred in the moderate to very high susceptible zones.展开更多
This work investigated the land-use/land-cover and some physico-chemical properties of the soils of Mt Cameroon and presented same in maps. ArcGIS Pro mapping software, Landsat images, Global Positioning Systems (GPS)...This work investigated the land-use/land-cover and some physico-chemical properties of the soils of Mt Cameroon and presented same in maps. ArcGIS Pro mapping software, Landsat images, Global Positioning Systems (GPS) coordinates collected from the field combined with updated shape files from competent services were used to produce the location and land-use/land-cover maps. Sixteen topsoil samples (0 - 20 cm) were collected, 4 from each land use/cover category: farmland, forest, plantation and settlement, and analysed for soil pH, cation exchange capacity (CEC), bulk density, moisture content and soil texture, in the laboratory using standard analytical procedures. This data was used to produce spatial distribution maps using ordinary kriging, in ArcGIS Pro. The main terrestrial land use/cover categories comprised of the forest (mangrove, lowland, montane and sub-montane), agroforestry, plantations, grassland, settlement, cropland, shrubby savannah, and bare lava. Bulk density showed the highest values in settlement areas and least values under forest land-use categories. Soil moisture content exhibited a reverse trend compared to that of soil bulk density. Forest soils were the sandiest while soils in plantation agricultural land were the most clayey. The soils were slightly acidic to neutral with soils from agricultural land being more acidic (pH<sub>(water)</sub> = 5.43). It is discernible from the results that the conversion from forest to other land use/cover classes enhances soil degradation and that soil physico-chemical properties adequately serve as indicators of soil quality in the Mt Cameroon area.展开更多
The present study performed on the Angovia, Kokumbo, Hire and Agbaou sites consisted of mapping the environmental risks linked to artisanal gold mining activities in C?te d’Ivoire. An inventory was done by observing ...The present study performed on the Angovia, Kokumbo, Hire and Agbaou sites consisted of mapping the environmental risks linked to artisanal gold mining activities in C?te d’Ivoire. An inventory was done by observing the different phases of gold extraction and identifying the risks associated with these phases. Using a Geographic Information System (GIS), the representation of the spatial distribution of the pollution risks has been realized from indicator descriptives of the environmental sensitivity (i.e. slope, proximity to the watercourse, soil cover) and the transfer indicator (i.e. rainfall). The analysis of this map showed low sensitivity of mercury (Hg), arsenic (As), copper (Cu) and zinc (Zn) measured in the waters of the Hire and Agbaou localities, while moderate sensitivity in Kokumbo surface waters and high sensitivity for those of Angovia locality were observed. Moreover, analysis of Hg, As, Cu and Zn content spatial distribution maps in surface waters revealed that Hg and As come mainly from the artisanal mining activities for most localities. Among these metallic trace elements observed, only the Hg content was above the WHO Limit Values, 1994 (>0.001 mg·L-1). The continuous spread of metallic trace elements in surface water can pose serious health problems for people living around artisanal gold mining sites, hence the need to put in place a protection plan against contamination.展开更多
Earthquake induced landslides are one of the most severe geo-environmental hazards that cause enormous damage to infrastructure, property, and loss of life in Nuweiba area. This study developed a model for mapping the...Earthquake induced landslides are one of the most severe geo-environmental hazards that cause enormous damage to infrastructure, property, and loss of life in Nuweiba area. This study developed a model for mapping the earthquake-induced landslide susceptibility in Nuweiba area in Egypt with considerations of geological, geomorphological, topographical, and seismological factors. An integrated approach of remote sensing and GIS technologies were applied for that target. Several data sources including Terra SAR-X and SPOT 5 satellite imagery, topographic maps, field data, and other geospatial resources were used to model landslide susceptibility. These data were used specifically to produce important thematic layers contributing to landslide occurrences in the region. A rating scheme was developed to assign ranks for the thematic layers and weights for their classes based on their contribution in landslide susceptibility. The ranks and weights were defined based on the knowledge from field survey and authors experiences related to the study area. The landslide susceptibility map delineates the hazard zones to three relative classes of susceptibility: high, moderate, and low. Therefore, the current approach provides a way to assess landslide hazards and serves for geo-hazard planning and prediction in Nuweiba area.展开更多
Since creation of spatial data is a costly and time consuming process, researchers, in this domain, in most of the cases rely on open source spatial attributes for their specific purpose. Likewise, the present researc...Since creation of spatial data is a costly and time consuming process, researchers, in this domain, in most of the cases rely on open source spatial attributes for their specific purpose. Likewise, the present research aims at mapping landslide susceptibility at the metropolitan area of Chittagong district of Bangladesh utilizing obtainable open source spatial data from various web portals. In this regard, we targeted a study region where rainfall induced landslides reportedly causes causalities as well as property damage each year. In this study, however, we employed multi-criteria evaluation (MCE) technique i.e., heuristic, a knowledge driven approach based on expert opinions from various discipline for landslide susceptibility mapping combining nine causative factors—geomorphology, geology, land use/land cover (LULC), slope, aspect, plan curvature, drainage distance, relative relief and vegetation in geographic information system (GIS) environment. The final susceptibility map was devised into five hazard classes viz., very low, low, moderate, high, and very high, representing 22 km2 (13%), 90 km2 (53%);24 km2 (15%);22 km2 (13%) and 10 km2 (6%) areas respectively. This particular study might be beneficial to the local authorities and other stake-holders, concerned in disaster risk reduction and mitigation activities. Moreover this study can also be advantageous for risk sensitive land use planning in the study area.展开更多
The aim of this project was to prepare and study a hazard map of Nagadhunga-Naubise section of the Tribhuvan highway. This section lies in the Middle Mountain region of Nepal. For the preparation of the hazard map of ...The aim of this project was to prepare and study a hazard map of Nagadhunga-Naubise section of the Tribhuvan highway. This section lies in the Middle Mountain region of Nepal. For the preparation of the hazard map of the corridor three steps, initial study, field investigation, and data analysis and presentation were carried out. In the initial study, the collection of available data and review of the literature were done. The base map was then prepared from the topographical map. In the field investigation step, all information and maps prepared earlier in the initial study were verified by field check. In the final step, prepared and verified data were then analyzed for the hazard mapping. Topography (gradient, slope shape and slope aspect), geology, drainage and land-use were considered to be the major influencing factors in the slope stability. Pre-assigned hazard rating method was used for hazard mapping of the study area. The area was divided into equal facets. Then ratings of responsible factors to the hazard were assigned to each facet and overlaid based upon a predetermined rating scheme. Total estimated hazard was the sum of these ratings for each overlay. Hazard map was prepared by using three categories as low hazard, medium hazard and high hazard. The Geographic Information System (GIS) was the main tool for the data input, analysis, and preparing of the final hazard map. The hazard map showed the areas of different hazard potential classes of;“low” with 32% portion, “Medium” with 51%, and “high” with 17% portion.展开更多
There is a growing need for web-based geographic information systems for easy and fast dissemination, sharing, displaying and processing of spatial information. The tremendous growth in the use of web and open-source ...There is a growing need for web-based geographic information systems for easy and fast dissemination, sharing, displaying and processing of spatial information. The tremendous growth in the use of web and open-source geospatial resources has sparked development of web-based spatial applications to address multidisciplinary issues with spatial dimensions. This paper presents the integration of open-source geospatial tools and web technology to visualize and interact with spatial data using web browser. The goal of this paper is to implement a prototype system for web-based mapping by providing step-by-step instructions in order to encourage the eager developers and interested readers to publish their maps on the web with no prior technical experience in map servers. The implementation of mapping prototype shows the utilization of open-source geospatial tools which results in a rapid implementation with minimal or no software input cost.展开更多
Objective:To identify the incidence rate,relative risk,hotspot regions and incidence trend of COVID-19 in Qom province,northwest part of Iran in the first stage of the pandemic.Methods:The study included 1125 official...Objective:To identify the incidence rate,relative risk,hotspot regions and incidence trend of COVID-19 in Qom province,northwest part of Iran in the first stage of the pandemic.Methods:The study included 1125 officially reported PCR-confirmed cases of COVID-19 from 20 February 2020 to 20 April 2020 in 90 regions in Qom city,Iran.The Bayesian hierarchical spatial model was used to model the relative risk of COVID-19 in Qom city,and the segmented regression model was used to estimate the trend of COVID-19 incidence rate.The Poisson distribution was applied for the observed number of COVID-19,and independent Gamma prior was used for inference on log-relative risk parameters of the model.Results:The total incidence rate of COVID-19 was estimated at 89.5 per 100000 persons in Qom city(95%CI:84.3,95.1).According to the results of the Bayesian hierarchical spatial model and posterior probabilities,43.33%of the regions in Qom city have relative risk greater than 1;however,only 11.11%of them were significantly greater than 1.Based on Geographic Information Systems(GIS)spatial analysis,10 spatial clusters were detected as active and emerging hotspot areas in the south and central parts of the city.The downward trend was estimated 10 days after the reporting of the first case(February 7,2020);however,the incidence rate was decreased by an average of 4.24%per day(95%CI:−10.7,−3.5).Conclusions:Spatial clusters with high incidence rates of COVID-19 in Qom city were in the south and central regions due to the high population density.The GIS could depict the spatial hotspot clusters of COVID-19 for timely surveillance and decision-making as a way to contain the disease.展开更多
国土规划“一张图”工程能够实现城市规划的高效性、科学性、合理性、整体性,是打造智慧城市的重要载体,然而目前“一张图”工程基于传统设备进行外业数据采集的方式已经不能全面满足当前的需求。针对传统模式下实地数据核查技术手段落...国土规划“一张图”工程能够实现城市规划的高效性、科学性、合理性、整体性,是打造智慧城市的重要载体,然而目前“一张图”工程基于传统设备进行外业数据采集的方式已经不能全面满足当前的需求。针对传统模式下实地数据核查技术手段落后、效率低下等问题,基于智能终端的管理信息系统将使“一张图”工程通过与移动端结合,使用移动智能终端取代传统的纸笔记录,简化野外数据核查的流程,在实际应用中为外业工作人员提供了便捷、高效的调绘核查方式,从而进一步增强了GIS系统的应用程度。本文以通州区数据为例,结合GIS基本理论,在Android操作系统的基础上,运用Arcgis for Android API,设计基于Android的通州区图斑管理系统,实现通州区国土规划一体化管理。系统主要实现地图基本浏览、查询、分析、测量等功能,形成了一套离线模式下的便捷查阅、浏览、分析图斑现状与规划信息的完整系统,提高了日常办公及使用效率,实现了高效资源监管。展开更多
A detailed landslide susceptibility map was produced in the Youfang catchment using logistic regression method with datasets developed for a geographic information system(GIS).Known as one of the most landslide-prone ...A detailed landslide susceptibility map was produced in the Youfang catchment using logistic regression method with datasets developed for a geographic information system(GIS).Known as one of the most landslide-prone areas in China, the Youfang catchment of Longnan mountain region,which lies in the transitional area among QinghaiTibet Plateau, loess Plateau and Sichuan Basin, was selected as a representative case to evaluate the frequency and distribution of landslides.Statistical relationships for landslide susceptibility assessment were developed using landslide and landslide causative factor databases.Logistic regression(LR)was used to create the landslide susceptibility maps based on a series of available data sources: landslide inventory; distance to drainage systems, faults and roads; slope angle and aspect; topographic elevation and topographical wetness index, and land use.The quality of the landslide susceptibility map produced in this paper was validated and the result can be used fordesigning protective and mitigation measures against landslide hazards.The landslide susceptibility map is expected to provide a fundamental tool for landslide hazards assessment and risk management in the Youfang catchment.展开更多
Turkey is highly prone to landslides because of the geological and geographic location.The study area,which is located in a tectonically active region,has been significantly affected by mass movements.Flow type landsl...Turkey is highly prone to landslides because of the geological and geographic location.The study area,which is located in a tectonically active region,has been significantly affected by mass movements.Flow type landslides are frequently observed due to this location.This study aims at determining the source area and propagation of debris flows in the study area.We used the heuristic method to extract source areas of debris flow,and then used receiver operating characteristic(ROC)curve analysis to assess the performance of the method,and finally calculated the Area under curve(AUC)values being 83.64%and 80.39%for the success rate and prediction rate,respectively.We calculated potential propagation area and runout distance with Flow-R software.In conclusion,the obtained results(susceptibility map,propagation and runout distance)are very important for decisionmakers at the region located on an active fault zone,which is highly prone to natural disasters.The outputs of this study could be used in site selection studies,designing erosion prevention systems and protecting existing human-made structures.展开更多
In recent years, global warming has gradually become obvious, thus created the climate change. Typhoon Morakot attacked Taiwan and brought heavy rainfall in August, 2009. In mountainous areas including Central and Sou...In recent years, global warming has gradually become obvious, thus created the climate change. Typhoon Morakot attacked Taiwan and brought heavy rainfall in August, 2009. In mountainous areas including Central and South Taiwan, the flood and debris flow disasters were induced by the typhoon. In this study, Changhua City is selected as the research region and the Delphi method is employed to interview experts and establish comprehensive evaluation criteria for assessing the evacuation plan on disaster areas. The concept is to combine the landslide potential analysis by geographic information systems with the flood or debris flow maps into the potential hazard map. Meanwhile, analytic hierarchy method (AHP) is comprehensively carried on the expert questionnaire survey for the potential hazard map of the compound disaster states. It should be useful for the local government and native people in the future.展开更多
With the flourish of Digital Earth and Digital Urban, Digital Mine is also imperative. The most fundamental condition for Digital Mine is mastering multiple spatial and property data. Various drawing materials and pro...With the flourish of Digital Earth and Digital Urban, Digital Mine is also imperative. The most fundamental condition for Digital Mine is mastering multiple spatial and property data. Various drawing materials and property data for mine industry provided by mine surveying workers in our country over the past half century will be the foundation of Digital Mine. The authors believe that the first step of Digital Mine is to develop basic mine geographic information system (for short MGIS), based on which Web Mine Geographic Information System can be set up. Besides when selecting software desk, including system softwares, supporting softwares, tool softwares and other auxiliary softwares, following standard, compatiblity, transplantation and co-operation, the function and efficiency of the selected software environment, as well as the supporting and expansion of adopting new technology should all be considered.展开更多
Terrain characteristics of the land and meteorological properties of the region are the main natural factors for flood. The recent flood in Chennai was unexpected and not triggered by the above factors. Sometimes floo...Terrain characteristics of the land and meteorological properties of the region are the main natural factors for flood. The recent flood in Chennai was unexpected and not triggered by the above factors. Sometimes floods occur when the watershed size is considerably small which leads to the over flow of water inland may due to the encroachment and the urban development of the city. Temporarily used backwater effects in sewers and local drainage channels and creation of unsanitary conditions may cause flooding. Chennai flood was basically claimed to occur due to improper drainage system and underlying strata which was found to be landfill over the ponds and lakes. The Coouam River which flows through the centre of main city was found silting due to the improper drainage facilities and encroachment by the local peoples who causes flood. For the analysis of potentially affected areas Geographical Information System (GIS) integrated with Multicriteria Decision Analysis (MCDA) were employed. Ranking and displaying the potentially risky areas, the spatial Multicriteria analysis was used. It has been revealed that all most all the area’s having populations are likely to be exposed to flood hazard. At the end of study, a map of flood risk areas was generated and studied with a view to assisting decision makers on the consequences posed by the disaster.展开更多
Local featured program in Indonesia cannot be separated entirely from commodity strategic bases. Until in 2006, agricultural development formulation showed indicative targets for featured crops commodity production. T...Local featured program in Indonesia cannot be separated entirely from commodity strategic bases. Until in 2006, agricultural development formulation showed indicative targets for featured crops commodity production. The problem of food security is forming of farmer’s independence to protect local resources in efficiently and optimally, so these resources can be more utilized. It can be achieved by assist of information technologies and communication in forming of Geographic Information System (GIS) to support consistency of food security in Indonesia. This research designs prototype geographic information system in order to conduct the accurate mapping and to know the local featured crops production in Indonesia. This level is conducted for documentation and mapping of agricultural products which is the local featured production. This documentation requires the usage of potential physical, economic, social and cultural environment by the utilization of information technology and communication, which have the ability of relevancy and accessibility of reliable information.展开更多
基金supported by the National Administration of Surveying, Mapping and Geoinformation (Grant no.1469990324229)the National Natural Science Foundation of China (Grant nos.40806076, 41176172, 41176173)+2 种基金the National High Technology Research and Development Program of China (Grant no. 2008AA121702–5)the National Science and Technology Infrastructure Program of China (Grant no.2006BAB18B01)the Chinese Arctic and Antarctic Administration, SOA(Grant no. 20070206)
文摘Antarctic surveying, mapping and remote sensing is one of the important aspects of the Chinese Antarctic geoscience research program that stretch back over 25 years, since the first Chinese National Antarctic Research Expedition (CHINARE) in 1984. During the 1980's, the geodetic datum, height system and absolute gravity datum were established at the Great Wall and Zhongshan Stations. Significant contributions have been made by the construction of the Chinese Great Wall, Zhongshan and Kunlun Stations in Antarctica. Geodetic control and gravity networks were established in the King George Islands, Grove Moun- tains and Dome Argus. An area of more than 200 000 km2 has been mapped using satellite image data, aerial photogrammetry and in situ data. Permanent GPS stations and tide gauges have been established at both the Great Wall and Zhongshan Stations. Studies involving plate motion, precise satellite orbit determination, the gravity field, sea level change, and various GPS applications for atmospheric studies have been carried out. Based on remote sensing techniques, studies have been undertaken on ice sheet and glacier movements, the distributions of blue ice and ice crevasses, and ice mass balance. Polar digital and visual mapping tech- niques have been introduced, and a polar survey space database has been built. The Chinese polar scientific expedition manage- ment information system and Chinese PANDA plan display platform were developed, which provides technical support for Chi- nese polar management. Finally, this paper examines prospects for future Chinese Antarctic surveying, mapping and remote sens- ing.
文摘Average credit scores for people in the United States (US) differ from state to state. Some states have high, and some states have low average credit scores. Since lenders and employers use credit scores to make loan and employment decisions, people living in states where average credit scores are high should experience the benefits of living where credit scores tend to allow more favorable loan and employment decisions. Although credit scores are the direct result of credit histories, credit histories may be impacted by demographic factors. If the demographic factors that impact credit histories are identified, ways to improve credit scores are likely to be discovered and available to people and state government policymakers. This study looks for demographic factors to indirectly explain the average credit scores for people living in each state of the US. The methodology includes statistical analyses and geographic information systems (GIS) mapping. Statistical analyses provide evidence to suggest that state average credit scores are explained by the demographic factors of education, family, income, and health. GIS mapping reveals clusters of states with similar demographics and credit scores.
文摘Cadastral maps are an important component of land administration in most countries. In virtually all developed countries, the needs of computerized land and geographic information systems (LIS/GIS) has given urgent impetus to computerizing cadastral maps and creating digital cadastral data bases (DCDB). This process is creating many institutional, legal, technical and administrative problems. This desire to establish DCDBs is being given increased impetus due to a new range of enabling technologies such as satellite position fixing (GPS), improved spatial data collection techniques such as digital theodolites and “soft copy” photogrammetry, as well as a vast range of new information and communications technological tools, thus contributing to the advancement and keeping up with the great countries. This paper presents the problem of cadastral maps. The hitherto existing cadastre, consisting of paper maps and land registers, is now becoming insufficient. Its shortcomings force developments leading to its improvement. One of the ways is the creation of a Land Information System. A digital cadastral map is the main component of this system. The structure and information content of the map is presented, its differences from analogue maps are shown, and the process of map creation is described. A digital cadastral map can be the basis for additional thematic layers, successively converting it into a complex system for management of administrative units.
文摘Defining the spatial extent of mountain areas has long been a challenge. In the present century, the availability of digital elevation models(DEMs) incorporated into geographic information systems(GIS) has allowed the definition of mountain areas based on topographic and other criteria. This paper presents the various delineations of mountains that have been prepared at three scales – global, regional(Europe), and national – and explores the reasons and processes leading to these delineations, and how they have been used. A detailed case study is then presented for Norway. Overall, two types of approaches to mapping mountains have been taken: first, considering mountains per se, based on elevation and/or topography; second, considering them among other categories, e.g., landforms or biogeographical, environmental or landscape zones. All attempts to map mountain areas derive essentially from the objectives of those commissioning and/or undertaking the work; a unitary definition remains unlikely.
文摘District Ghizer is a rugged mountainous territory which experiences several landslides each year. There are 16 major landslide areas and 53 villages that are at high risk to hazards. Keeping in view the severity of natural hazards, the present study was designed to generate landslide susceptibility map based on twelve causative factors viz., slope, aspect, elevation, drainage network, Stream Power Index (SPI), Topographic Wetness Index (TWI), lithological units, fault lines, rainfall, road network, land cover and soil texture. Soil texture was determined by particle size analysis and data for other factors were acquired from freely available sources. Analytical Hierarchy Process (AHP) was employed to identify major landslide causative factors in the district Ghizer. Further, a temporal assessment from 1999 till 2015 was generated to assess the impact of land cover change on landslides. It indicated that the barren soil/ exposed rocks and glaciers have reduced while the vegetation and water classes have shown increment. The total area that lies in moderate to very high landslide susceptible zones was 74.38%, while slope is the main landslide causative factor in the district Ghizer. Validation of the susceptibility map showed 88.1% of the landslides in the study area had occurred in the moderate to very high susceptible zones.
文摘This work investigated the land-use/land-cover and some physico-chemical properties of the soils of Mt Cameroon and presented same in maps. ArcGIS Pro mapping software, Landsat images, Global Positioning Systems (GPS) coordinates collected from the field combined with updated shape files from competent services were used to produce the location and land-use/land-cover maps. Sixteen topsoil samples (0 - 20 cm) were collected, 4 from each land use/cover category: farmland, forest, plantation and settlement, and analysed for soil pH, cation exchange capacity (CEC), bulk density, moisture content and soil texture, in the laboratory using standard analytical procedures. This data was used to produce spatial distribution maps using ordinary kriging, in ArcGIS Pro. The main terrestrial land use/cover categories comprised of the forest (mangrove, lowland, montane and sub-montane), agroforestry, plantations, grassland, settlement, cropland, shrubby savannah, and bare lava. Bulk density showed the highest values in settlement areas and least values under forest land-use categories. Soil moisture content exhibited a reverse trend compared to that of soil bulk density. Forest soils were the sandiest while soils in plantation agricultural land were the most clayey. The soils were slightly acidic to neutral with soils from agricultural land being more acidic (pH<sub>(water)</sub> = 5.43). It is discernible from the results that the conversion from forest to other land use/cover classes enhances soil degradation and that soil physico-chemical properties adequately serve as indicators of soil quality in the Mt Cameroon area.
文摘The present study performed on the Angovia, Kokumbo, Hire and Agbaou sites consisted of mapping the environmental risks linked to artisanal gold mining activities in C?te d’Ivoire. An inventory was done by observing the different phases of gold extraction and identifying the risks associated with these phases. Using a Geographic Information System (GIS), the representation of the spatial distribution of the pollution risks has been realized from indicator descriptives of the environmental sensitivity (i.e. slope, proximity to the watercourse, soil cover) and the transfer indicator (i.e. rainfall). The analysis of this map showed low sensitivity of mercury (Hg), arsenic (As), copper (Cu) and zinc (Zn) measured in the waters of the Hire and Agbaou localities, while moderate sensitivity in Kokumbo surface waters and high sensitivity for those of Angovia locality were observed. Moreover, analysis of Hg, As, Cu and Zn content spatial distribution maps in surface waters revealed that Hg and As come mainly from the artisanal mining activities for most localities. Among these metallic trace elements observed, only the Hg content was above the WHO Limit Values, 1994 (>0.001 mg·L-1). The continuous spread of metallic trace elements in surface water can pose serious health problems for people living around artisanal gold mining sites, hence the need to put in place a protection plan against contamination.
基金the Egyptian Ministry of Higher Education and Scientific Research
文摘Earthquake induced landslides are one of the most severe geo-environmental hazards that cause enormous damage to infrastructure, property, and loss of life in Nuweiba area. This study developed a model for mapping the earthquake-induced landslide susceptibility in Nuweiba area in Egypt with considerations of geological, geomorphological, topographical, and seismological factors. An integrated approach of remote sensing and GIS technologies were applied for that target. Several data sources including Terra SAR-X and SPOT 5 satellite imagery, topographic maps, field data, and other geospatial resources were used to model landslide susceptibility. These data were used specifically to produce important thematic layers contributing to landslide occurrences in the region. A rating scheme was developed to assign ranks for the thematic layers and weights for their classes based on their contribution in landslide susceptibility. The ranks and weights were defined based on the knowledge from field survey and authors experiences related to the study area. The landslide susceptibility map delineates the hazard zones to three relative classes of susceptibility: high, moderate, and low. Therefore, the current approach provides a way to assess landslide hazards and serves for geo-hazard planning and prediction in Nuweiba area.
文摘Since creation of spatial data is a costly and time consuming process, researchers, in this domain, in most of the cases rely on open source spatial attributes for their specific purpose. Likewise, the present research aims at mapping landslide susceptibility at the metropolitan area of Chittagong district of Bangladesh utilizing obtainable open source spatial data from various web portals. In this regard, we targeted a study region where rainfall induced landslides reportedly causes causalities as well as property damage each year. In this study, however, we employed multi-criteria evaluation (MCE) technique i.e., heuristic, a knowledge driven approach based on expert opinions from various discipline for landslide susceptibility mapping combining nine causative factors—geomorphology, geology, land use/land cover (LULC), slope, aspect, plan curvature, drainage distance, relative relief and vegetation in geographic information system (GIS) environment. The final susceptibility map was devised into five hazard classes viz., very low, low, moderate, high, and very high, representing 22 km2 (13%), 90 km2 (53%);24 km2 (15%);22 km2 (13%) and 10 km2 (6%) areas respectively. This particular study might be beneficial to the local authorities and other stake-holders, concerned in disaster risk reduction and mitigation activities. Moreover this study can also be advantageous for risk sensitive land use planning in the study area.
文摘The aim of this project was to prepare and study a hazard map of Nagadhunga-Naubise section of the Tribhuvan highway. This section lies in the Middle Mountain region of Nepal. For the preparation of the hazard map of the corridor three steps, initial study, field investigation, and data analysis and presentation were carried out. In the initial study, the collection of available data and review of the literature were done. The base map was then prepared from the topographical map. In the field investigation step, all information and maps prepared earlier in the initial study were verified by field check. In the final step, prepared and verified data were then analyzed for the hazard mapping. Topography (gradient, slope shape and slope aspect), geology, drainage and land-use were considered to be the major influencing factors in the slope stability. Pre-assigned hazard rating method was used for hazard mapping of the study area. The area was divided into equal facets. Then ratings of responsible factors to the hazard were assigned to each facet and overlaid based upon a predetermined rating scheme. Total estimated hazard was the sum of these ratings for each overlay. Hazard map was prepared by using three categories as low hazard, medium hazard and high hazard. The Geographic Information System (GIS) was the main tool for the data input, analysis, and preparing of the final hazard map. The hazard map showed the areas of different hazard potential classes of;“low” with 32% portion, “Medium” with 51%, and “high” with 17% portion.
文摘There is a growing need for web-based geographic information systems for easy and fast dissemination, sharing, displaying and processing of spatial information. The tremendous growth in the use of web and open-source geospatial resources has sparked development of web-based spatial applications to address multidisciplinary issues with spatial dimensions. This paper presents the integration of open-source geospatial tools and web technology to visualize and interact with spatial data using web browser. The goal of this paper is to implement a prototype system for web-based mapping by providing step-by-step instructions in order to encourage the eager developers and interested readers to publish their maps on the web with no prior technical experience in map servers. The implementation of mapping prototype shows the utilization of open-source geospatial tools which results in a rapid implementation with minimal or no software input cost.
文摘Objective:To identify the incidence rate,relative risk,hotspot regions and incidence trend of COVID-19 in Qom province,northwest part of Iran in the first stage of the pandemic.Methods:The study included 1125 officially reported PCR-confirmed cases of COVID-19 from 20 February 2020 to 20 April 2020 in 90 regions in Qom city,Iran.The Bayesian hierarchical spatial model was used to model the relative risk of COVID-19 in Qom city,and the segmented regression model was used to estimate the trend of COVID-19 incidence rate.The Poisson distribution was applied for the observed number of COVID-19,and independent Gamma prior was used for inference on log-relative risk parameters of the model.Results:The total incidence rate of COVID-19 was estimated at 89.5 per 100000 persons in Qom city(95%CI:84.3,95.1).According to the results of the Bayesian hierarchical spatial model and posterior probabilities,43.33%of the regions in Qom city have relative risk greater than 1;however,only 11.11%of them were significantly greater than 1.Based on Geographic Information Systems(GIS)spatial analysis,10 spatial clusters were detected as active and emerging hotspot areas in the south and central parts of the city.The downward trend was estimated 10 days after the reporting of the first case(February 7,2020);however,the incidence rate was decreased by an average of 4.24%per day(95%CI:−10.7,−3.5).Conclusions:Spatial clusters with high incidence rates of COVID-19 in Qom city were in the south and central regions due to the high population density.The GIS could depict the spatial hotspot clusters of COVID-19 for timely surveillance and decision-making as a way to contain the disease.
文摘国土规划“一张图”工程能够实现城市规划的高效性、科学性、合理性、整体性,是打造智慧城市的重要载体,然而目前“一张图”工程基于传统设备进行外业数据采集的方式已经不能全面满足当前的需求。针对传统模式下实地数据核查技术手段落后、效率低下等问题,基于智能终端的管理信息系统将使“一张图”工程通过与移动端结合,使用移动智能终端取代传统的纸笔记录,简化野外数据核查的流程,在实际应用中为外业工作人员提供了便捷、高效的调绘核查方式,从而进一步增强了GIS系统的应用程度。本文以通州区数据为例,结合GIS基本理论,在Android操作系统的基础上,运用Arcgis for Android API,设计基于Android的通州区图斑管理系统,实现通州区国土规划一体化管理。系统主要实现地图基本浏览、查询、分析、测量等功能,形成了一套离线模式下的便捷查阅、浏览、分析图斑现状与规划信息的完整系统,提高了日常办公及使用效率,实现了高效资源监管。
基金supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(164320H101)the Opening Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection of Chengdu University of Technology,China(SKLGP2012K012)+4 种基金the Opening Fund of Key Laboratory for Geo-hazards in Loess area(GLA2014005)the National Natural Science Foundation of China(No.40801212 and No.41201424)the 973 National Basic Research Program(Nos.2013CB733203,2013CB733204)the 863 National High-Tech Rand D Program(No.2012AA121302)the FP6 project"Mountain Risks"of the European Commission(No.MRTNCT-2006-035798)
文摘A detailed landslide susceptibility map was produced in the Youfang catchment using logistic regression method with datasets developed for a geographic information system(GIS).Known as one of the most landslide-prone areas in China, the Youfang catchment of Longnan mountain region,which lies in the transitional area among QinghaiTibet Plateau, loess Plateau and Sichuan Basin, was selected as a representative case to evaluate the frequency and distribution of landslides.Statistical relationships for landslide susceptibility assessment were developed using landslide and landslide causative factor databases.Logistic regression(LR)was used to create the landslide susceptibility maps based on a series of available data sources: landslide inventory; distance to drainage systems, faults and roads; slope angle and aspect; topographic elevation and topographical wetness index, and land use.The quality of the landslide susceptibility map produced in this paper was validated and the result can be used fordesigning protective and mitigation measures against landslide hazards.The landslide susceptibility map is expected to provide a fundamental tool for landslide hazards assessment and risk management in the Youfang catchment.
文摘Turkey is highly prone to landslides because of the geological and geographic location.The study area,which is located in a tectonically active region,has been significantly affected by mass movements.Flow type landslides are frequently observed due to this location.This study aims at determining the source area and propagation of debris flows in the study area.We used the heuristic method to extract source areas of debris flow,and then used receiver operating characteristic(ROC)curve analysis to assess the performance of the method,and finally calculated the Area under curve(AUC)values being 83.64%and 80.39%for the success rate and prediction rate,respectively.We calculated potential propagation area and runout distance with Flow-R software.In conclusion,the obtained results(susceptibility map,propagation and runout distance)are very important for decisionmakers at the region located on an active fault zone,which is highly prone to natural disasters.The outputs of this study could be used in site selection studies,designing erosion prevention systems and protecting existing human-made structures.
文摘In recent years, global warming has gradually become obvious, thus created the climate change. Typhoon Morakot attacked Taiwan and brought heavy rainfall in August, 2009. In mountainous areas including Central and South Taiwan, the flood and debris flow disasters were induced by the typhoon. In this study, Changhua City is selected as the research region and the Delphi method is employed to interview experts and establish comprehensive evaluation criteria for assessing the evacuation plan on disaster areas. The concept is to combine the landslide potential analysis by geographic information systems with the flood or debris flow maps into the potential hazard map. Meanwhile, analytic hierarchy method (AHP) is comprehensively carried on the expert questionnaire survey for the potential hazard map of the compound disaster states. It should be useful for the local government and native people in the future.
文摘With the flourish of Digital Earth and Digital Urban, Digital Mine is also imperative. The most fundamental condition for Digital Mine is mastering multiple spatial and property data. Various drawing materials and property data for mine industry provided by mine surveying workers in our country over the past half century will be the foundation of Digital Mine. The authors believe that the first step of Digital Mine is to develop basic mine geographic information system (for short MGIS), based on which Web Mine Geographic Information System can be set up. Besides when selecting software desk, including system softwares, supporting softwares, tool softwares and other auxiliary softwares, following standard, compatiblity, transplantation and co-operation, the function and efficiency of the selected software environment, as well as the supporting and expansion of adopting new technology should all be considered.
文摘Terrain characteristics of the land and meteorological properties of the region are the main natural factors for flood. The recent flood in Chennai was unexpected and not triggered by the above factors. Sometimes floods occur when the watershed size is considerably small which leads to the over flow of water inland may due to the encroachment and the urban development of the city. Temporarily used backwater effects in sewers and local drainage channels and creation of unsanitary conditions may cause flooding. Chennai flood was basically claimed to occur due to improper drainage system and underlying strata which was found to be landfill over the ponds and lakes. The Coouam River which flows through the centre of main city was found silting due to the improper drainage facilities and encroachment by the local peoples who causes flood. For the analysis of potentially affected areas Geographical Information System (GIS) integrated with Multicriteria Decision Analysis (MCDA) were employed. Ranking and displaying the potentially risky areas, the spatial Multicriteria analysis was used. It has been revealed that all most all the area’s having populations are likely to be exposed to flood hazard. At the end of study, a map of flood risk areas was generated and studied with a view to assisting decision makers on the consequences posed by the disaster.
文摘Local featured program in Indonesia cannot be separated entirely from commodity strategic bases. Until in 2006, agricultural development formulation showed indicative targets for featured crops commodity production. The problem of food security is forming of farmer’s independence to protect local resources in efficiently and optimally, so these resources can be more utilized. It can be achieved by assist of information technologies and communication in forming of Geographic Information System (GIS) to support consistency of food security in Indonesia. This research designs prototype geographic information system in order to conduct the accurate mapping and to know the local featured crops production in Indonesia. This level is conducted for documentation and mapping of agricultural products which is the local featured production. This documentation requires the usage of potential physical, economic, social and cultural environment by the utilization of information technology and communication, which have the ability of relevancy and accessibility of reliable information.