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International Journal of Digital Earth 2011年第5期4卷 387-401页

作者： V.Prasannakumar RShiny NGeetha HVijith Centre for Geoinformation Science and Technology University of KeralaKariavattomThiruvananthapuramKerala 695581India

Geomorphologic and hydrologic research heavily depends on digital elevation models(DEM)which are currently being prepared from digital *** present study examines the use and applicability of freely available global elevation data source(3 arc seconds finished Shuttle Radar Topography Mission(SRTM))in landform characterisation,geomorphometry,river basin studies and other allied scientific applications in comparison with contour elevation data derived from the surveyed topographical *** relief data extracted from a conventionally digitised geo-information science dataset of topographic contours(1:50,000)are compared with the SRTM-DEM and the variations are *** automated geomorphometric and landform parameters derived from the contour DEM and the computed statistical properties of those parameters have substantial agreement with the same parameters derived from the *** the same time,localised variations also exist in some spatial *** landscape analysis outputs from the SRTM-DEM suggest the wide acceptability and applicability of the freely available SRTM data source,especially in the regional scale applications related to hydrological modelling,terrain characterisation,disaster management and land degradation studies.

关键词： geomorphometry landform characterisation SRTM wetness index terrain position index

Chinese progress in geomorphometry

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Journal of Geographical Sciences 2017年第11期27卷 1389-1412页

作者： LV Guonian XIONG Liyang CHEN Min TANG Guoan SHENG Yehua LIU Xuejun SONG Zhiyao LU Yuqi YU Zhaoyuan ZHANG Ka WANG Meizhen Key Laboratory of Virtual Geographic Environment Ministry of Education of PRC Nanjing Normal University Nanjing 210023 China State Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province) Nanjing 210023 China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Ap- plication Nanjing 210023 China School of Geography science Nanjing Normal University Nanjing 210023 China

geomorphometry, the science of digital terrain analysis （DTA）, is an important focus of research in both geomorphology and geographical information science （GIS）. Given that 70% of China is mountainous, geomorphological research is popular among Chinese schol- ars, and the development of GIS over the last 30 years has led to significant advances in geomorphometric research. In this paper, we review Chinese progress in geomorphometry based on the published literature. There are three major areas of progress： digital terrain modelling methods, DTA methods, and applications of digital terrain models （DTMs）. First, traditional vector- and raster-based terrain modelling methods, including the assessment of uncertainty, have received widespread attention. New terrain modelling methods such as unified raster and vector, high-fidelity, and real-time dynamic geographical scene modelling have also attracted research attention and are now a major focus of digital terrain modelling research. Second, in addition to the popular DTA methods based on topographical derivatives geomorphological features, and hydrological factors extracted from DTMs, DTA methods have been extended to include analyses of the structure of underlying strata, ocean surface features and even socioeconomic spatial structures. Third, DTMs have been applied to fields including global climate change, analysis of various typical regions, lunar surface and other related fields. Clearly, Chinese scholars have made significant progress in geomorphometry. Chinese scholars have had the greatest international impact in areas including high-fidelity digital terrain modelling and DTM-based regional geomorphological analysis, particularly in the Loess Plateau and the Tibetan Plateau regions.

关键词： geomorphometry digital terrain model digital terrain analysis progress China

Landslide inventory validation and susceptibility mapping in the Gerecse Hills, Hungary

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Geo-Spatial Information Science 2021年第3期24卷 498-508页

作者： Dávid Gerzsenyi Gáspár Albert Department of Cartography and Geoinformatics Eötvös Loránd UniversityBudapestHungary

Landslides pose a threat to property both in the populated and cultivated areas of the Gerecse Hills (Hungary). The currently available landslide inventory database holds the records from many sites in the area, but the database is out-of-date. Here we address the problem of revising the National Landslides Cadastre landslide inventory database by creating a landslide suscept-ibility map with a multivariate model based on likelihood ratio functions. The model is applied to the TanDEM-X DEM (0.4″ res.), the current landslide inventory of the area, and data acquired from geological maps. By comparing the distributions of four variables in the landslide and non-landslide area with grid computation methods, the model yields landslide susceptibility estimates for the study area. The estimations show to what extent a certain area is similar to the sample areas, therefore, its likelihood to be affected by landslides in the future. The accuracy of the model predictions was checked in the field and compared to the results of our previous study using the SRTM-1 DEM for a similar analysis. The model gave accurate estimates when certain correction measures were applied to the input datasets. The limitations of the model, the input datasets, and the suggested correction measures are also discussed.

关键词： Landslide susceptibility landslide inventory TanDEM-X Gerecse Hills landslides geomorphometry

Geomorphic signatures of active tectonics in Subansiri River Basin, eastern Himalayas

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Journal of Mountain Science 2020年第6期17卷 1523-1540页

作者： Diganta KUMAR Bhagawat Pran DUARAH Department of Geological Sciences Gauhati UniversityGuwahatiAssam-781014India

The Subansiri,a major tributary of the Brahmaputra with its catchment area(35763 km^2)spreading almost entirely in the Eastern Himalayas across almost all the major and local tectonic features in the area witnesses large numbers of seismic *** tectonic indices like relief and slope,drainage pattern,longitudinal profile,valley profile,hypsometry,valley asymmetry factors and transverse topographic symmetry index,stream length gradient,valley floor-height ratio extracted from SRTM 3 arcsecond data prove that the evolving basin morphology has substantial contribution from the Himalayan *** data are incorporated in the study to establish the potentially active tectonic elements in the catchment *** study shows that the western part of the Subansiri River Basin is profoundly tilted towards north in the upper catchment and towards east in the lower and middle part of the *** predominant tectonic movements in the western part of the basin caused the tilting of the basin towards north in the upstream and towards east in the middle and lower parts.

关键词： Eastern Himalayas Active tectonics Subansiri geomorphometry SRTM DEM Seismicity

Impact of geomorphometric parameters on the occurrence and distribution of landslides in Yamuna River Basin,North-Western Himalaya,India

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Journal of Mountain Science 2022年第8期19卷 2374-2396页

作者： Ravi SHANKAR Gyan Prakash SATYAM Prakash Kumar SINGH Nilesh Kumar RAI Ranjit Kumar PASWAN REED CSIR-Central Institute of Mining and Fuel ResearchDhanbad 826001India Department of Applied Geology Indian Institute of Technology(ISM)Dhanbad 826004India Department of Earth and Planetary Sciences University of AllahabadPrayagraj 211002Uttar PradeshIndia

The majority of landslides in the Indian Himalayas are triggered by rainfall and *** geology and geomorphology also play an important role and constitute the major predisposing factor controlling ***,active tectonics modify the landscape,impacting the occurrence and distribution of *** objective of this study is to investigate the role of some of the major predisposing factors to assess landslide patterns in the Yamuna River Basin as it is prone to recurrent landslide *** approach mainly deals with the application of geographical information system-based statistical analysis and quantifying frequency-area distribution of rainfalltriggered landslides for the years 2015 to *** analysis shows that the frequency of landslides is highest in the slope range 40°-70°and the mean landslide size is higher in the slope range 0°-20°and 30°-40°,remaining constant on further increase in slope *** study shows that some critical slope range controls both the frequency and size of *** were mostly restricted to south facing *** 91%of the landslide occur in the drainage density range of 1.2 to 2.1 km/km^(2) while landslides show very low occurrence in either lower(2.1)drainage *** distribution analysis of landslides depicts a distinct cutoff point but an indistinct rollover ***-sampling of small landslides can be a reasonable cause for *** other studies,the present data fits very well for medium and large landslides following an inverse power law with a scaling exponent *** 80% of landslides are smaller than the cutoff size and 20% larger than this *** geology and tectonics of Lesser Himalayas and Sivaliks offer favorable conditions for frequent *** such as Dehradun,Uttarkashi,Sirmaur,Shimla,and Solan are very prone to landslide activity owing to the presence of poorly consolidated sandstone,conglomerate,quartzites,phylli

关键词： Himalaya geomorphometry Landslide Yamuna River Basin

GIS tools for preliminary debris-flow assessment at regional scale

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Journal of Mountain Science 2017年第12期14卷 2498-2510页

作者： cavalli marco crema stefano trevisani sebastiano marchi lorenzo consiglio nazionale delle ricerche istituto di ricerca per la protezione idrogeologicaCorso Stati Uniti 435127 PadovaItaly universitàdi padova dipartimento territorio e sistemi agro-forestaliVia dell’Universita 1635020 Legnaro(PD)Italy universitàiuav di venezia dipartimento di architettura costruzione conservazioneDorsoduro 220630123 VeneziaItaly

The assessment of the areas endangered by debris flows is a major issue in the context of mountain watershed management. Depending on the scale of analysis, different methods are required for the assessment of the areas exposed to debris *** 2-D numerical models are advised for detailed mapping of inundation areas on individual alluvial fans, preliminary recognition of hazard areas at the regional scale can be adequately performed by less data-demanding methods, which enable priority ranking of channels and alluvial fans at risk by debris flows. This contribution focuses on a simple and fast procedure that has been implemented for regionalscale identification of debris-flow prone channels and prioritization of the related alluvial fans. The methodology is based on the analysis of morphometric parameters derived from Digital Elevation Models(DEMs). Potential initiation sites of debris flows are identified as the DEM cells that exceed a threshold of slope-dependent contributing area. Channel reaches corresponding to debris flows propagation, deceleration and stopping conditions are derived from thresholds of local slope. An analysis of longitudinal profiles is used for the computation of the runout distance of debris flows. Information on erosion-resistant bedrock channels and sediment availability surveyed in the field are taken into account in the applications. A set of software tools was developed and made available(https://***/Hydrogeomorphology Tools) to facilitate the application of the procedure. This approach, which has been extensively validated by means of field checks, has been extensively applied in the eastern Italian Alps. This contribution discusses potential and limitations of the method in the frame of the management of small mountain watersheds.

关键词： Debris flow Geographic information system Digital elevation models Runout Alluvial fan Watershed management geomorphometry

Geomorphometric relief classification with the κ-median method in the Silesian Upland,southern Poland

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Frontiers of Earth Science 2020年第1期14卷 152-170页

作者： Bartlomiej SZYPULA Malgorzata WIECZOREK Institute of Earth Sciences Faculty of Natural SciencesUniversity of Silesia in KatowiceSosnowiec 41-200Poland Department of Geoinformatics and Cartography Faculty of Earth Sciences and Environment ManagementUniversity of WroclawWroclaw 50-137Poland

The aim of this study is geomorphometric relief classification of a temperate latitude upland area in Central *** Silesian Upland represents diversified structural relief which contains a fan-shaped configuration of long thresholds and wide erosion depressions.A 20 m × 20 m digital elevation model(DEM)provided input data for the *** κ-median method was applied to examine morphometric variables of the *** aim of these activities was to identify clusters with objects of similar mathematical *** clusters were the basis of landform *** numbers of clusters 4 transparently show hypsometric *** elements of the morphology of the area were clearly *** division into 6 clusters gives the best results-a detailed but clear image of the morphological diversity by distinguishing characteristic landform *** results for 8 clusters show significant background noise and are ambiguous,which makes them diflBcult to *** research has confirmed that the κ-median method is a useful tool for landform *** determined optimal parameters of this method(filtering window size,DEM resolution,number of clusters,aspect influence).

关键词： κ-median method relief classifications digital elevation model(DEM) geomorphometry Silesian Upland

Assessment of the Relationships among Catchments’ Morphometric Parameters and Hydrologic Indices

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International Journal of Geosciences 2014年第13期5卷 1571-1583页

作者： Sotirios Karalis Efthimios Karymbalis Kanella Valkanou Christos Chalkias Petros Katsafados Kleomenis Kalogeropoulos Vasileios Batzakis Antonios Bofilios Department of Geography Harokopio University of Athens Athens Greece

In Greece the hydrological analysis of ephemeral streams has been especially difficult due to the lack of precipitation and discharge gauges. This study focuses on the investigation of possible relationship between morphometric characteristics of small to medium drainage basins and hydrological indices in order to discover morphometric parameters “predictors” of flash flood potential of ungauged catchments. Twenty-two morphometric parameters of twenty-seven drainage basins (ranging in area between 3.6 km2 and 330.5 km2) located in the northern part of the Peloponnese in southern Greece were calculated utilizing GIS software ArcGIS10. Hydrological modeling was performed using a simplified Matlab implementation of TOPMODEL, a conceptual model based on the principle of variable contributing area to runoff production through saturated overland flow, and LISEM, a physically based hydrologic and soil erosion model. Rainfall-runoff simulations were performed for an extreme precipitation event. The simulations outcomes, which include the peak discharge, time to peak and the percentage runoff, were correlated with the morphometric parameters of the catchments. Results were not consistent between the two models, probably due to their different structure, with the LISEM results being closer to what is anticipated. The results demonstrate that area, length of the basin, perimeter and compactness factor appear better correlated with the peak discharge (Qpeak) of the catchment. The same parameters as well as Melton’s number correlate with percentage runoff (C), while “celerity” of the flood wave (length of the basin/time to peak) is better correlated with relief, indicating that as the relief becomes greater, the response of the basin becomes fastest.

关键词： geomorphometry Hydrologic Modeling TOPMODEL LISEM Greece