Morphometry using remote sensing and GIS techniques in the sub-basins of Kagna river basin, Gulburga district, Karnataka, India

The study area is a part of Kagna river basin in the Gulburga district of Karnataka, India. It covers an area of 1320 km² and it has been subdivided into 4 sub-basins namely Wadi, Chitapur, Sedam and Kurkunta, which range in area from 184 to 537 km². The drainage pattern of these sub-basins are delineated using Geo-coded FCC bands 2,3,4 of IRS 1C and 1D(LISS III+PAN merged) on 1:50,000 scale and Survey of India toposheets as reference. The morphometric parameters are computed using ArcInfo and ArcView GIS softwares. The drainage pattern of the study area is dendritic to sub-dendritic with stream orders ranging from IV to VII orders. Drainage density ranges from 1.40 to 1.86 km/km² suggesting coarse to moderate drainage texture. The change in values of stream length ratio indicate their late youth stage of geomorphic development. The values of bifurcation ratio ranging from 2.00 to 4.71 indicate that all the sub-basins fall under normal basin category. The values of form factor and circulatory ratio, suggest that the Kurkunta sub-basin is elongated and the remaining sub-basins are more or less circular in shape. Elongation ratio indicates that the Wadi sub-basin is a region of very low relief whereas the other sub-basins are associated with moderate to high relief and steep ground slopes. It is concluded that remote sensing and GIS have been proved to be efficient tools in drainage delineation and updation. In the present study these updated drainages have been used for the morphometric analysis.     

A GIS-based glacier inventory for the Antarctic Peninsula and the South Shetland Islands —A first case study on King George Island

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Nature,1992,355(6 360):503 ［30］Stark P.Climatic warming in the central Antarctic Peninsula area.Weather,1994,49(6):215～220 ［31］Turner J,Colwel S R,Harangozo S.Variability of precipitation over the coastal western Antarctic Peninsula from synoptic observations.Journal of Geophysical Research,1997,102(D12):13 999～14 007 ［32］Warren C R.Iceberg calving and the glaciomarine record.Progress in Physical Geography,1992,16(3):253～282 ［33］Wunderle S.Die Schneedeckendynamik der Antarkische Halbinsel und ihre Erfassung mit aktiven und passiven Fernerkundungsverfahren.Freiburger Geographische Hefte,1996,48:172 ［34］Braun M,Saurer H,Vogt S,Simes J C,et al.The influence of large_scale atmospheric circulation on surface energy balance on the ice cap of King George Island.International Journal of Climatology,2001,21(1):21～36     

Morphotectonic analysis in Anandpur Sahib area,Punjab (India) using remote sensing and gis approach

Anandpur Sahib area of Rupnagar district (Punjab) was investigated using an integrated multi-disciplinary approach of geomorphological, structural, drainage and morphotectonic analysis through satellite data and GIS. Most commonly used geomorphic indices viz., channel sinuosity, drainage basin asymmetry, basin elongation ratio, mountain front sinuosity and valley floor to valley width ratio index have been used to identify the geomorphic indicators of active tectonics in the area. Existence of fluvial anomalies viz., abrupt changes in flow direction, flow against gradient, beheaded streams and river terraces reflect the strong structural control on the fluvial features. Asymmetric nature of drainage basin, elongated nature of the sub-watersheds, straight to curvilinear mountain fronts and narrow incised valley floors further substantiate the role of active tectonics in the region.     

A GIS-based glacier inventory for the Antarctic Peninsula and the South Shetland Islands —A first case study on King George Island

The aim of the international project “Global Land Ice Measurements from Space (GLIMS)” headed by the US Geological Survey is to establish a world wide glacier inventory based on satellite imagery. This data set will form a first digital baseline study for future glacier monitoring. The presented GIS-based glacier inventory for King George Island is a case study for the area of the Antarctic Peninsula. In the database of the glacier inventory topographic information, specific glaciological parameters as well as metadata will be included. The topographic data consists of drainage basin limits, basin areas, altitudinal ranges, perimeters and mean lengths. Glaciological data sets should comprise information on glacier retreat in different periods, glacier velocities, ice thickness and bedrock topography as well as derived parameters. Modelled and measured mass balance parameters could be included as additional data layers. In particular, these metadata records must comprise background information on data accuracy and data sources and should be compatible with a future data model for the King George Island GIS (KGIS). Three examples illustrate that the GLIMS database will not only contain information valuable for glaciological applications, but also other environmental studies on the island will benefit from this standardised remote sensing data sets. Therefore, a very close link between the data models of KGIS and GLIMS has to be established to enable these synergisms. Finally, better access to historic aerial photography would enable a continuous record of glacier retreat from the beginning of the 1950's onward.     

Morphometric analysis of sub-watersheds in the pavagada area of Tumkur district,South India using remote sensing and gis techniques

The study area covers 570 km² comprising of 9 sub-watersheds (Dalavayihalli, Maddalenahalli, Talamaradahalli, Puluvalli tank, Nagalamadike, Gowdatimmanahalli, Naliganahalli, Devadabetta and Byadanur) range from 49 to 75 km² forming part of Pennar river basin around Pavagada. The drainage network of 9 sub-watersheds was delineated using remote sensing data - Geocoded FCC of bands - 2 3 4 of IRS 1 C and 1 D (LISS III+PAN merged) on 1:50,000 scale and SOI topomaps were used as reference. The morphometric analysis of 9 sub-watersheds has been carried out using GIS softwares - Arclnfo and Are View. The drainage network shows that the terrain exhibits dendritic to sub-dendritic drainage pattern. Stream orders ranges from fourth to fifth order. Drainage density varies between 1.55 and 2.16 km/ km² and has very coarse to coarse drainage texture. The relief ratio range from 0.006 to 0.021. The mean bifurcation ratio varies from 3.21 to 4.88 and falls under normal basin category. The elongation ratio shows that Devedabetta sub-watershed possesses circular shape while remaining sub-watersheds mark elongated pattern. Hence from the study it can be concluded that remote sensing techniques proved to be a competent tool in morphometric analysis.     

A GIS-BASED GLACIER INVENTORY FOR THE ANTARCTIC PENINSULA AND THE SOUTH SHETLAND ISLANDS——A FIRST CASE STUDY ON KING GEORGE ISLAND

1　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅＷｏｒｋｉｎｇＧｒｏｕｐｏｎＧｅｏｄｅｓｙａｎｄＧｅｏｇｒａｐｈｉｃＩｎｆｏｒｍａｔｉｏｎ (ＷＧ＿ＧＧＩ)ｏｆｔｈｅＳｃｉｅｎｔｉｆｉｃＣｏｍｍｉｔ ｔｅｅｏｎＡｎｔａｒｃｔｉｃＲｅｓｅａｒｃｈ (ＳＣＡＲ )ｌａｕｎｃｈｅｄｔｈｅｐｒｏｊｅｃｔＫｉｎｇＧｅｏｒｇｅＩｓｌａｎｄＧＩＳ (ＫＧＩＳ) .Ｉｎｏｒｄｅｒｔｏｐｒｏｖｉｄｅａｎｏｐｅｒａｔｉｏｎａｌｓｙｓｔｅｍ ,ａｄａｔａｍｏｄｅｌ,ｄａｔａａｃｃｕｒａｃｙｓｔａｎｄａｒｄｓａｎｄａｄａｔａｉｎｖｅｎｔｏｒｙｈａｖ…     

基于多时相Landsat TM/ETM的阿尼玛卿山冰川变化监测

采用遥感及地理信息系统技术,利用多时相Landsat TM/ETM影像和数字高程模型(SRTMDEM),结合中国冰川目录,获得阿尼玛卿山地区不同年份的冰川范围,进行冰川变化监测。综合分析该冰川的变化情况,计算冰川进退变化速率,并对其中4个变化较大的冰川进行详细的分析统计。结果表明:从1991年至2009年,阿尼玛卿山地区既有退缩冰川也有前进冰川,其中冰川退缩面积为15.30km2,前进面积为4.46km2。总体面积持续退缩,其中退缩最大的冰川长度缩短了900m,其它冰川也存在不同程度的变化。     

Recession of samudra tapu glacier, chandra river basin, Himachal Pradesh

Himalayas possess one of the largest resources of snow, ice and glaciers that act as a huge freshwater reservoir. Monitoring the glaciers is important to assess the overall reservoir health of the Himalayas. Samudra Tapu is one of the largest glaciers in Chandra basin of district Lahaul and Spiti, Himachal Pradesh. Based on the field investigations and the remote sensing techniques. features such as accumulation area, ablation area snowline/equilibrium line, moraine-dammed lakes and permanent snowfields were mapped. The glacial terminus was identified using moraine-dammed lake, as lake is located at down streamside of the terminus. The total recession of glacier during the period of 38 years (1962–2000) is about 742 m with an average rate of 19.5 m/yr. In addition, glacial extent is reduced from 73 to 65 km² between 1962 and 2000. suggesting overall deglaciation of 11%. During field investigation. three stages of glaciation using terminal moraine were identified. These moraines were mapped by merging LISS-II1 and PAN data. At the peak of glaciation. the glacial terminus was extended 3.18 km downstream of terminus position in year 2000. Total area during peak of glaciation period has been observed to be 77.67 km², which is 12.67 km² higher than the present glacier extent.     

基于遥感和GIS的洪水坝河流域冰川变化研究

以洪水坝河流域为例,利用1956年的地形图和2003年的ASTER遥感影像及数字高程模型,在GIS的支持下对两期数据进行统计分析,结果表明:近47年来,洪水坝河流域冰川面积减少了14.04%,长度退缩了17.28%,储量减少了2.26%。研究认为,气温显著升高是洪水坝河流域冰川快速萎缩的主要原因。在和祁连山地区、西藏以及天山地区的冰川进行对比后,发现研究区冰川消融的速率介于三地之间,初步推测是由研究区所在区域的气候和自身属性共同作用的结果。     

Mapping the mega paleodrainage basin using shuttle radar topography mission in Eastern Sahara and its impact on the new development projects in Southern Egypt

In the current study, the shuttle radar topography mission (SRTM) data, with ～90 m horizontal resolution, were used to delineate the paleodrainage system and their mega basin extent in the East Sahara area. One mega-drainage basin has been detected, covering an area of 256 000 km2. It is classified into two sub mega basins. The Uweinate sub mega basin, which is composed of four main tributaries, collected water from a vast catchment region and drained eastward from the north, west, and southwest, starting at highland areas. The first subwatershed basin is in the northern plateau, south of the Abu-Balas area, with a total catchment area of 25 045 km2. The second subwatershed is in the Gilf Kebir plateau and has a total catchment area of 38 257 km2. The third subwatershed drains from the Uweinate highlands and has a catchment area of 46 154 km2. The fourth subwatershed, which is known in literature as Wadi Mokhtafi in its upper reach and Wadi Arid in its lower reach, drains the northwestern highlands of Sudan and has a total catchment area of 28 653 km2. The Tushka sub mega basin includes one watershed that drains from the northeast highlands of Sudan and has a total catchment area of 63 019 km2. The Uweinate and Tushka sub mega basins are joined together to the North of the Tushka depression, which drains northward toward the Kharga depression. This study indicates that the Eastern Sahara Mega Basin is a closed hydrological system independent of the other drainage systems, such as the Nile hydrosystem and the Qena Valley system. The present research illustrates the capability of the SRTM data in mapping the paleochannel networks, as well as estimate the catchment area and direction of the water flow. Finally, the study reveals that the four areas could be potentially used for different reclamation activities due to the ground water accumulations possibilities.     

基于GIS和TM影像的水库水位面积曲线测定

利用GIS软件,以大汶河流域雪野水库近年的TM影像为基础资料,根据GIS的栅格数据矢量化处理应用原理进行了水库库区矢量和栅格文件的处理,提出了基于GIS技术的水库水域面积的提取分析方法,结合水文统计观测数据,得到水库汛期水位面积曲线,相比传统的水库面积量算方法,具有快速、精准、效率高的优势,大大简化了测量过程。为水库更进一步的水文分析奠定了基础。     

Comparison of basin morphometry derived from topographic maps,ASTER and SRTM DEMs: an example from Kerala,India

The drainage network of a sixth-order tropical river basin, viz. Ithikkara river basin, was extracted from different sources such as Survey of India topographic maps (1: 50,000; TOPO) and digital elevation data of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) (30 m) and Shuttle Radar Topography Mapping Mission (SRTM) (90 m). Basin morphometric attributes were estimated to evaluate the accuracy of the digital elevation model (DEM)-derived drainage networks for hydrologic applications as well as terrain characterization. The stream networks derived from ASTER and SRTM DEMs show significant agreement (with slight overestimation of lower order streams) with that of TOPO. The study suggests that SRTM (despite the coarser spatial resolution) provides better results, in drainage delineation and basin morphometry, compared to ASTER. Further, the variability of basin morphometry among the data sources might be attributed to spatial variation of elevation, raster grid size and vertical accuracy of the DEMs as well as incapability of the surface hydrologic analysis functions in the GIS platform.     

GIS-based morphometric analysis of five major sub-watersheds of Song River,Dehradun District,Uttarakhand with special reference to landslide incidences

Evaluation of the morphometric parameters requires preparation of drainage map, contour map, ordering of the various streams and measurements of catchment area, perimeter, relative relief, relief ratio, length of drainage channels, drainage density, drainage frequency, bifurcation ratio, texture ratio, circulatory ratio and constant channel maintenance, which help to understand the nature of the drainage basin. The present study involves the Geographic Information System (GIS) analysis techniques to evaluate and compare linear, relief and aerial morphometry of the five subwatersheds of Song River (tributary of the Ganga River) with special reference to landslide incidences, for future development and planning of the watershed. Jakhan Rao, Song River, Bandal Nadi, Baldi Nadi and Suswa Nadi are the five major subwatersheds of the Song River basin. All the subwatersheds are basically of 5^th to 6^th order. Drainage patterns are mainly dendritic to sub dendritic. The drainage pattern of the Song River basin is mainly structurally controlled and the area is characterized by high to moderate relief. The asymmetric factor indicates that the tectonic rotation of the four subwatersheds is upward on the right side of the drainage basin and only one sub-watershed is downward. The numbers of the landslide incidences are also more in the upward side, than the downward side of the Song River basin.     

Runoff Estimation and Morphometric Analysis for Hesaraghatta Watershed Using IRS–1D LISS III FCC Satellite Data

The study area, Hesaraghatta watershed is located between 77° 20′ to 77° 42′ E longitude and 13° 10′ to 13° 24′ N latitude with an area of 600.01 km². Thematic layers such as Land Use/Land Cover, drainage, soil and hydrological soil group were generated from IRS–1D LISS III satellite data (FCC). An attempt was made to estimate runoff using Soil Conservation Service (SCS) curve number model and it was estimated to be 1960, 2066, 1870 and 1810 mm for sub-watersheds 1, 2, 3 and 4 respectively. Quantitative morphometric analysis was carried out for the entire watershed and the four sub-watersheds independently by estimating their (a) linear aspects like stream order, stream length, stream length ratio, bifurcation ratio, length of overland flow, drainage pattern (b) aerial aspects like shape factor, circulatory ratio, elongation ratio and drainage density and (c) relief aspects like basin relief, relief ratio, relative relief and ruggedness number. Drainage density was estimated to be 1.23 km/km² designating the study area as a very coarse textured watershed.     

Runoff modelling of a small watershed using satellite data and GIS

This study was conducted for the Nagwan watershed of the Damodar Valley Corporation (DVC), Hazaribagh, Bihar, India. Geographic Information System (GIS) was used to extract the hydrological parameters of the watershed from the remote sensing and field data. The Digital Elevation Model (DEM) was prepared using contour map (Survey of India, 1:50000 scale) of the watershed. The EASI/PACE GIS software was used to extract the topographic features and to delineate watershed and overland flow-paths from the DEM. Land use classification were generated from data of Indian Remote Sensing Satellite (IRS-1B—LISS—II) to compute runoff Curve Number (CN). Data extracted from contour map, soil map and satellite imagery, viz. drainage basin area, basin shape, average slope of the watershed, main stream channel slope, land use, hydrological soil groups and CN were used for developing an empirical model for surface runoff prediction. It was found that the model can predict runoff reasonably well and is well suited for the Nagwan watershed. Design of conservation structures can be done and their effects on direct runoff can be evaluated using the model. In broader sense it could be concluded that model can be applied for estimating runoff and evaluating its effect on structures of the Nagwan watershed.     

Mapping and classification of hydrological parameters from digital terrain data in the Musandam Peninsula,UAE and Oman

Groundwater exploration and modelling requires hydrological parameters and a large volume of hydrologic database. This study integrates remote sensing and geographic information system (GIS) to map and classify hydrological parameters indicates areas of groundwater recharge and discharge. Bivariate quadratic surfaces with moving window size of 5 × 5 were fitted to the digital elevation model and drainage basins, drainage network, topographic wetness index (TWI) and hydroforms were derived. The eight-direction algorithm (D8) that determines in which neighbouring pixel any water in a central pixel will flow naturally was used to delineate drainage basin and drainage network in the study area. The TWI was used to quantify the effect of local topography on hydrological processes and for modelling soil moisture. The results indicate the presence of intensive of stream network (1336 km²), wettest zones and accumulation zones (63.99 km²) within Wadi Bih, the UAE and Wadi Khasb, Oman, suggesting regional recharge.     

Updated Inventory of Glacial Lakes in Teesta Basin Using Remote Sensing Data for Use in GLOF Risk Assessment

Detailed inventory of glacial lakes in a Glacial Lake Outburst Flood (GLOF) prone area is vital for disaster mitigation. Availability of cheaper high resolution satellite data from Indian remote sensing satellites enables us to create up-to-date inventory for use in prioritisation of glacial lakes for GLOF risk assessment. Earlier inventories show presence of more glacial lakes in Brahmaputra basin in Indian Himalaya. Teesta River is one of the tributary of Brahmaputra and previous studies have shown that the inventory of glacial lakes in Teesta basin varies from 143 to 320. In the present study, the inventory carried out using satellite data of years 2000, 2007 and 2014 show presence of 301 (25.789 km²), 302 (26.081 km²) and 644 (29.706 km²) glacial lakes in Teesta basin respectively. The steep increase in number of lakes in the latest inventory is primarily due to the finer spatial resolution of satellite data used. Analysis of water spread area of glacial lakes at different altitudes shows that most of the lakes in the higher altitudes are small in size. It is observed that more than 66% of lakes are in the altitude beyond 4500 m and of size less than 50,000 sqm (5 ha). Out of 301 glacial lakes inventoried during 2000, water spread area of 6 lakes have decreased in 2014 and 31 lakes have shown increase in area. Out of these 31 lakes, 17 lakes are classified as end moraine dammed lakes and among them, 14 are located in Upper Teesta sub-basin and in higher altitudes (beyond 5000 m). The prioritisation of these lakes for GLOF risk needs to be carried out with detailed field investigation.     

Landsat imagery analysis and field studies in the Kullu and Chauhar valleys,Himachal Pradesh,India

The rough terrain between the Gogar Dhar (Mandi-Brot rise) and the Kullu-Larji valley is geologically unexplored. This paper brings out for the first time the geology and regional tectonic set-up of the area on the basis of LANDSAT imagery interpretation and field checks. Image analysis of about 3700 sq. km area and field observations along selected sections of the area reveal that the area mainly comprises mica-chlorite schists, quartzites and phyllites i.e. low to medium grade Chail metamorophics with acid and basic intrusions within them. Structually the rocks are arranged in the form of a NNW-SSE trending faulted synclinorium, the axis of which passes through Daggi Dhar. The western flank of the synclinorium is more strongly folded. Granitoids and basics show concordent relations with the country rocks. Two belts of granitoids are found occupying the cores of the folds on both the limbs of the synclinorium. Along the Uhl river (in the Chauhar valley) and the Kullu valley passes the Chail thrust separating the Chail metamorphics from the rocks of the outer carbonate belt and the traps of the Mandi unit, and the inner carbonate belt of the Larji window zone respectively. The area is dissected into blocks by cross cutting, deep-seated major faults of three generations. The fold and fault systems have prominent control over the geomorphology including the drainage patterns and landforms of the area. The present area is a typical case of inverted relief, anticlinal valleys and synclinal hills being the main geomorphic features developed due to structural control. The change in the course of the Beas River between Mandi and Pandoh is a typical case of structural control on the present drainage system.     

Glacier inventory in Himachal Pradesh using satellite images

A total of 125 glaciers covering an area of 1896 sq. km. were mapped on 1:250,000 scale in Himachal Pradesh using satellite images. The areal extent obtained from satellite images was found to be comparable with that from field estimates for eight glaciers for which data are available. This suggests that remote sensing can provide glacial areal extent similar to ground-based methods. Depth of an individual glacier was inferred indirectly by using its relationship with areal extent and geomorphological characteristics, as suggested by Muller (1970). These characteristics were estimated by using satellite images. The analysis suggests that the water equivalent of the glaciers in Himachal Pradesh is about 165 cu km. It is seventeen times more than the storage capacity of the Govind Sagar. This estimate will get revised when other snow/ice features as permanent snow field, ice apron, hanging glaciers and rocky glaciers are mapped. Mapping on larger scale, say 1:50,000, will lead to a further revision as many smaller glaciers and other features will get mapped.     

Groundwater Prospect Zoning Using Remote Sensing and Geographical Information System: A Case Study in Dala-Renukoot Area, Sonbhadra District, Uttar Pradesh

In the present study, ground water prospect zones in Dala-Renukoot area, in Sonebhadra district. Uttar Pradesh, India have been delineated, through integration of various thematic maps using ARC/INFO GIS. Thematic maps in respect of geology, geomorphology. slope, drainage, land-use/land cover, lineament and lineament intersection frequency were prepared on 1:50,000 scale using remote sensing and conventional methods. These maps were scanned and registered with reference to a basemap and are input as separate layers using ARC/INFO GIS. Each theme was assigned a weightage depending on its influence on the movement and storage of groundwater and each unit in every theme map is assigned a knowledge based ranking from 1 to 5 depending on its significance to groundwater occurrence. All the themes are overlaid, two at a time and the resultant composite coverage is classified into five groundwater prospect categories. This output map is correlated with the groundwater data collected in the field.