Studying town morphology through Remote Sensing

Remotely-sensed data products have got unique advantage over conventional data-gathering techniques in the study of urban morphology. The physical parameters like built-up area density, street pattern, population density, urban structure as well as functional characteristics which can be derived from land use/land cover map, are clearly visible on aerial data products. This technique provides synoptic view of the area which makes the study comprehensive and uniform. Sequential aerial photographs and satellite imagery help in studying the growth of urban area and temporal changes in urban structure. These informations are very useful in the planning of city extension. Here an attempt has been made to study the urban morphology of Saharanpur city by using panchromatic aerial photographs on scale 1∶10,000, IRS-1B LISS II geocoded imagery on 1∶50,000 scale and photo-maps on 1∶4000 scale, and the results are very encouraging.     

Geology of the area around Badami,Bijapur District,Karnataka state—A study based on interpretation of remotely sensed data

Geological studies in the area around Badami, Bijapur District, Karnataka, were carried out with the help of Landsat imagery and aerial photographs. The study are forms a part Kaladgi Basin which is located on the northernmost fringes of the exposed Dharwar Craton. Archaen Peninsular Gneiss and intrusive Granodiorite/Granites (≈Clospet Granite) form the basement for the Middle to Late Proterozoic Kaladgi Super Group sediments which are, in turn, overlain in the north by the Upper Cretaceous to Lower Eocene Deccan flood basalt lavas. Geological mapping of the study area and inferences about the structural setup were primarily based on interpretation of the remotely sensed data. The combined interpretative study of Landsat imagery and aerial photographs was instrumental in mapping of the lithostratigraphic units exposed in the study area along with the structures associated with them.     

Interpretation of Synthetic Aperture Radar (SAR) imagery for geological appraisal: A comparative study in Anantapur district of Andhra Pradesh

The paper describes the details of a comparative study of geological interpretations carried out from Synthetic Aperture Radar (SAR) imagery, Landsat MSS (B & W) imagery and Aerial Photographs, covering 2100 sq km of area in Anantapur district of Andhra Pradesh. The area comprises Peninsular—Gneissic Complex and rocks of Dharwar and Cuddapah Super Groups beside the Quaternary alluvial deposits along the Penneru river and its tributaries. Geomorphologically the areas is represented by denudational, fluvial and structural landforms. The study indicates that the details of the geological and geomorphological maps prepared from SAR imagery and aerial photographs are comparable despite the smaller scale of SAR imagery while the same are not exhibited in Landsat imagery mainly due to its low resolution. Although broad lithological units are possible to be discriminated on SAR as well as aerial photographs, some of the finer rock types viz. gabbroic dykes could be discriminated from the delerite dykes in the SAR imagery due to their different surface roughness. Stereoscopic coverage and enhanced micro-relief of SAR imagery gives better geomorphological details in comparison to aerial photographs. A detailed study of lineaments has also been carried out which shows that in SAR imagery there is over-representation of short lineaments due to enhanced micro-relief and radarshadow effects across the look direction and under-representation of lineaments along the look direction. Landsat imagery is perhaps the best for demarcating lineaments of regional magnitude while aerial photographs are good for depicting shorter lineaments. However, certain lineaments seen in SAR imagery are often not continuously seen on aerial photographs.     

GIS-based geomorphological mapping using remote sensing data and supplementary geoinformation: A case study of the Dhaka city area,Bangladesh

This study aims to prepare a detailed GIS-based geomorphological map accompanied with landfill sites of Dhaka city area which can be used for multipurpose functionality. Attainment of the geomorphological map is based upon interpretation of the oldest available aerial photographs (1:40,000) and contemporary topographic maps (1:8000) which reflect almost pre-urban ground of Dhaka. Randomly distributed 160 boreholes have been used to prepare representative soil profiles (RSP) to identify the near-surface lithology of the geomorphological units. The study reveals that 13 out of 18 low-lying geomorphic units, comprising 65% of the total area demand landfill practices for urban development. Landfill sites have been merged with urban growth on each low-lying geomorphic unit using a spatially enhanced fused image of IRS-1D PAN and ETM+ bands 5, 4 and 3, acquired February 2000 and 2002, respectively. We found that 43% area of the total low-lying geomorphic units experience fill practices so far. The fill sites have been differentiated into four classes based on their relative thickness. Integration of fill classes with geomorphological map shows the urban dynamics of Dhaka city area till 2002. Due to GIS integration, this map can be rapidly updated to demonstrate temporal modifications in urban ground. It can be used effectively in different geomorphological hazard mapping and urban land-use practices.     

Residential area evaluation using GIS technique: A case study — Part of Bhubaneswar city

To evaluate a planning area or to implement plan procedures, planners need database in the form of land use, population density, housing density and point information regarding various facilities. At present planning tasks are carried out by manual methods where analytical capabilities are limited. Therefore, there is a need for reliable data as well as comprehensive database information indicating physical factors and good analytical tools. In a development plan various standards are specified in zoning regulations for the development of a city. To get an overall view, how these standards are implemented on the ground in planning period, a GIS application can be useful in analysing various amenity standards with respect to population and distances. In this study, for part of Bhubaneswar, basic data was generated from 1988 aerial photographs and other related information was gathered through field survey and secondary sources. The derived information in the form of a map has been entered into computer through digitization. Vector information was later converted into a raster form for the analysis. As per the planning standards catchment areas were created for limited facilities/services like schools, parks, play ground and accessibility to bus stop from main road. The population actually served by these facilities were calculated and compared with the existing planning standards. This particular study demonstrates the use of GIS in one of the planning tasks especially analyzing the residential areas as per the set standards such that improvement schemes can be proposed accordingly in the deficient areas.     

Geology of the area around Katta,sindhudurg district,Maharashtra. Based on aerospace data

Geological studies of the area around Katta, in the southern part of the Ratnagiri District of Maharashtra, were carried out with the help of visual remote sensing techniques using LANDSAT imageries on 1:250,000 scale and aerial photographs on 1:60,000 scale. The major stratigraphic units represented in the area under study are the Archean Complex, Kaladgi Supergroup, Deccan Trap, Laterite and Alluvium. The Kaladgis unconformably overlie the Archean metasediments and also at places exhibit faulted contacts with the latter. The major part of the area is covered by a thick evergreen vegetation. The interpretation followed by field work and laboratory work revealed the following:

1. The different lithologic units could be delineated on the aerial photographs.
2. Different lineaments marked on the imagery were found to be due either to faults or fracture zones. Some of the older faults appear to have been rejuvenated after the formation of the laterites.
3. Some of the lithologic horizons can be identified on the Landsat imagery by virtue of their spatial signatures.

These studies indicate that even in the area covered with thick vegetation, aerospace imagery in appropriate band and data scale can provide significant geological information.     

Soil—landscape relationship of Hissar District using aerial photo — interpretation technique

Soil survey of Hissar district (Haryana) covering total area of 6,331 sq. kms. was carried out using the aerial photographs of 1 : 25,000 scale. A detailed physiographic legend was prepared and boundaries were confirmed in relation to soil. Soil-landscape relationship was established during the course of study. Four major physiographic units were identified in the area : i. e. i) Aeolian plain, ii) Alluvial plain, iii) Drishdawati flood plain, iv) Ghaggar flood plain. Each of the major unit was sub-divided on the basis of photo elements, tone, texture, erosion, parcelling etc. The soils of the sand dunes/ Bars are classified as Typic Torripsamments/Ustipsamments; plain-Typic, Camborthids/Calciorthids/Ustrochrepts; basins-Aquic Ustochrepts and salt affected plain-Aquic Natrustalfs.     

Hydrogeomorphological mapping in ground water exploration using remotely sensed data — a case study in keonjhar district, orissa

Identification of fractures/lineaments and hydrogeomorphic units is prerequisite for undertaking ground water exploration and development in any terrain. Use of satellite remote sensing techniques coupled with aerial photo-interpretation greatly aid in planning ground water exploration, and pin pointing well sites In this study, airborne and space borne data was used for qualitative evaluation of ground water resources and a critical appraisal of such study in combination with hydrogeological and hydrogeophysical techniques for ground water exploration and development in Keonjhar district of Orissa. The study area has been divided into various geomorphic units based on visual interpretation of Landsat (TM) false colour composite on. 1:2,50,000 scale and the ground water potential of each of the units is qualitatively assessed. Digital image processing techniques such as principal component analysis and brightness index were used for generating classified outputs. The features like valley fills, pediments ete appeared clearly on the classified image. Directional filtering brought out minor fractures/lineaments crisply. The study has revealed the significance of different hydrogeomorptuc units and lineaments in Controlling ground water potential of the area. The findings were corroborated by resalts of drilling and resistivity soundings.     

Development of Information Evaluation System for Smart City Planning Using Geoinformatics Techniques

Urbanization is a continuous process, which transforms the traditional setup into the modern era. Uneven population growth over the next 3 decades is expected in cities. In this context, the new technology-based solutions are desirable, which can provide more efficient and robust approaches for urban infrastructure planning. Keeping these visions, the smart city concept is evolving in the developing countries like India, which appears a new paradigm of systematic intelligent urban infrastructure planning in the city. This research work comprises of grids-based, eight different land use and infrastructure-related information evaluation systems namely urban settlements information evaluation system, water resource information evaluation system, urban green space information evaluation system, intelligent transportation information evaluation system, basic infrastructure information evaluation system, power distribution information evaluation system, telecommunication mast information evaluation system and city surveillance information evaluation system for the development of smart city priority zones in the Bhopal city, capital of Madhya Pradesh, India. The LISS IV and Cartosat 1 sensor digital Image data along with ancillary data were used. The GPS survey was carried out to confirm ground realities, and digital intelligent map was prepared for various utilities after integration of thematic layers. The geostatistical analysis and weights-based methods were used for the creation of information evaluation system for city planning. The investigation of results have shown that various parameters related to smart city planning can be analyzed in a more efficient manner by dividing the area into an appropriate size grid. The spatial integration of information evaluation systems were carried out and areas were divided into low-, medium- and high-priority zones. These prominent categories such as high-priority zones covered the 14% of the study area, similarly medium-priority zones covered the 34% of the study area and low-priority zones covered the 52% of the study area. This research work investigations are very useful for the formulation of new strategic plans, in order to achieve better land use and infrastructure features utilization for the smart city planning.     

Geology and geomorphology of Cumbum valley and Varushanadu hills,Madural district,Tamil Nadu through remote sensing

The Varushanad hills forms the eastern offshoot of the Western Ghats and the Cumbum valley divides the Varushnad hills from the Western Ghats. Investigations were carried out in about 1700 sq Km comprising the Cumbum valley and the Varushanad hills of the Western Ghats situated in Periakulam Srivalliputhur and Usilampatti taluks of Tamil Nadu on the geological and geomorphological aspects. Remote sensing techniques were used and limited field checks were made. Visual interpretation of aerial photographs on 1:60,000 scale was carried out for identifying the geomorphological features, drainage pattern and lithology. Digital analysis of the Landsat computer compatible tape (CCT) path-row 154–053 was also carried out to delineate major lithological variations. Major lineaments were also mapped from the Landsat imagery and false colour composite. The rock types of the Cumbum valley and the Varushanad hills are mainly charnockites, granite gneiss and pink granites which have been deformed by folds and faults. The various geomorphological units of the area are ridges, valleys, bazada zone and pediment zone of mountain complex. Resources evalution studies on the potential zone of ground water and possible construction materials were also discussed.     

徐州市城市空间扩展与交通脉动研究

本文利用多时段TM影像图和城市规划图,采用GIS空间分析技术,运用象限方位分析方法对徐州市城市空间扩展强度、重心坐标等指数进行定量分析,生成交通建设与城市规模的相关系数矩阵,研究该市城市空间扩展与交通脉动的变化规律.结果表明:1979 2008年间,受城区主干道路、高速公路、高速铁路等重大交通设施建设影响,徐州市城市...     

Aerial remote sensing application in hydrogeological and geomorphic mapping of a rocky terrain: A case study from Uttar Pradesh

Ground water prospecting in hard rock areas of Uttar Pradesh is quite difficult, owing to the geological and geomorphic controls of sub-surface strata on the occurrence and movement of ground water resources, and, therefore, it requires systematic investigations, mainly with the aid of remotely sensed and data, which undoubtedly provide realistic information on the hydrogeological conditions, geomorphologic features, drainage patterns etc. of any rocky area. In this paper, an endeavour has been made to locate ground water possibilities in the drought-affected, rocky terrain of the southern Mirzapur district of Uttar Pradesh, covering part of block Muirpur which is mainly characterised by the varied geological formations, including Archean complex, pre-Vindhyan matasediments and Gondwana formation, through the application of air photointerpretation technique, primarily based on the geologic/geomorphologic approach. The hydro-investigation in the area was carried out using panchromatic aerial photos of 1∶60,000 scale, chiefly to identify the drainage patterns, major geomorphic geo structural and lithological units; as these may control the ground water regime of the area, Further. the present study was also ably supported with limited field survey and hydrogeological data, for achieving reliable results.     

基于消费级无人机的突兀大高差场地三维建模

智慧城市发展迅速,各地开展城市信息模型（CIM）基础平台建设的步伐不断加快,因而需要高效高质地构建不同类型场地的城市三维实景模型。本文针对传统航摄建模方法在突兀大高差场地三维模型重建中的不足,提出一种基于消费级无人机对突兀大高差场地进行阶梯式环绕拍摄航片并运用倾斜摄影技术对其进行三维建模的方法。同时运用该方法和传统模仿五镜头航摄的五架次航摄建模方法对桂林市南洲大桥进行对比试验。本文方法所重建的模型精度更高,效率得到提升,模型细节完整度更好。该方法能够高质高效地对突兀大高差场地进行三维重建,为CIM的创建提供更优的选择,促进智慧城市的发展。     

Land use study in Mewat area,Haryana, using remote sensing techniques

A soil and land use survey of Mewat area, Haryana, was carried out using the aerial photographs of 1:50,000. Four major physiographic units namely hills, piedmont plain, intermontante basin and Yamuna alluvial plain were recognised. The land use was studied in relation to the physiographic units. The legend adopted for land use classification has physiography at first level, utility at second level and management and identification at third and fourth levels respectively. Of the total area of 161,103 ha surveyed, 131,637 ha (81.72%) are cultivated. Of this 75,967 ha (47.16%) irrigated and 55,670 ha (34.56%) is unirrigated. Under uncultivated area, barren lands cover 14,224 ha (8.82%), forests occupy 3,463 ha (5.25%), settlements cover 3,300 (2.05%), water bodies occupy 1,312 ha (0.81%) and roads, railway lines, canals and drains constitute 2,167 ha (1.55%).     

航空摄影测量在地籍测量中的应用研究

航空摄影测量技术应用于地籍测量中具有工艺流程自动化程度高、工作量大幅度减少、成图周期短、生产成本低、测绘成果精度好等特点,能够完成城乡大比例尺地籍测量任务,在现代城乡建设规划领域备受青睐。用航空摄影测量方法能否实测大比例尺地籍图,其界址点精度如何?针对这一问题,本文详细介绍了航空摄影测量技术应用于地籍测量中的理论与方法,对这种方法进行了探索与研究,并结合辽宁省兴城市用航测方法测绘地籍图的生产实际,认真研究了其中存在的问题。重点介绍了利用航空摄影测量技术进行地籍测量的作业流程,并针对工艺流程中的精度规范问题进行讨论研究,分析影响作业效率和作业精度的原因,最后对航空摄影测量技术在地籍中的应用进行总结,并提出设想,展望在城市中的发展。     

Delineating ravinous areas on aerial photographs and satellite Imagery-A comparative study

Extensive areas along Yamuna, Chambal and their tributaries in Uttar Pradesh, Rajasthan and Madhya Pradesh have been severely eroded forming ravines of various depths. These areas offer great potential for the development of agriculture and forestry after reclamation. In order that they are reclaimed and managed properly, precise data on their nature and extent are needed. Morphometric analysis of ravine lands along Chambal and Kunwari rivers near Bhind, Madhya Presdesh has been carried out using 1:25,000 scale aerial photographs. Landsat imagery for the same area has been interpreted to find out the relative recognition of morphometric units earlier interpreted on air photos. It was observed that while aerial photographs provide data regarding depth, width, slope and frequency distribution of ravines at a greater detail, Landsat imagery helps in delineation of broad reclamative groupings which would be useful for Large Area Planning (LAP). A multistage approach involving the use of both air photos and satellite imagery seems to be the possible answer for preparing a Ravine Map of India.     

The geology and structure of the area south of Gani,Kurnool District,Andhra Pradesh — a study based on remotely sensed data

Geological investigations in the area south of Gani, Kurnool District, Andhra Pradesh, were carried out with the help of aerial Photographs and multiband satellite imageries. The rocks of the Cuddapah Group and the Kurnool Group are exposed in the area under study. The Gani-Kalava anticline and the ENE-WSW trending Kalava fault are the important structural features of the area. The anticlinal structure could be better studied using the aerial photographs, while the fault is clearer on the imagery. Small scale folds involving the Cuddapahs and the Kurnools along the northern limb of the fold could be mapped using the aerial photographs. The Gani-Kalava anticline is a post-Kurnool structure, formed by movement along the Kalava fault and in the first instance the minor folds appear to be drags on the northern limb. However, certain structural and stratigraphic relations suggest that the folding in the Cuddapahs may be a pre-Kurnool phenomenon.     

Confirmation of soil physiographic units through soil mineralogy studies in Yamuna alluvial plain,India

A confirmatory study of soil physiographic units identified through aerial photo interpretation technique, in Yamuna alluvial plain, Haryana is presented here. The area under study is part of Yamuna alluvial plain in Sonepat district, Haryana. Shanwal and Malik (1980) studied and mapped this area (semi-detailed) on 1:25,000 scale through areial photo interpretation technique. The soil profile samples of major soil physiographic units of the area were fractionated into sand, silt and clay. Detail mineralagical studies were carried out through electron microscopic and X-ray diffractometer studies in order to know their nature and origin of the parent material. X-ray diffraction data shows that mineralogy of different fractions (Sand, silt and clay) of soils samples, of different physiographic units were similar except Lavee. In this area mica is the dominant day mineral in the soils followed by Kaolinite, chlorite, vermiculite and smectite in decreasing order of their abundances. The occurance of fibrous minerals in coarse clay and silt fraction of soil samples of Lavee physiographic unit is the interesting feature of this area. The presence of fibrous minerals indicates that this overlain material designated as natural Levee in this area is not the alluvium brought down by the river Yamuna but is aeolian material flown from adjoining deseret of Rajasthan and deposited as stabilized sand dune. The fibrous minerals have been reported earlier in the desert of Rajasthan.     

Generating population census data through aerial remote sensing

For urban planning and decision making, exact information about population of a specific area is very important. In India, the population census is carried out after every decade by field survey. But to know the inter-censual population, field survey is not very appropriate method because it is not cost and time-effective. Remote sensing can help significantly in generating quick information about housing typology and housing stock, from which population data can be extracted with the help of limited field checks. Therefore, two techniques of estimation of population using remote sensing data have been employed for Saharanpur city as a case study and the results are very encouraging.     

DMC航摄影像外业像控布点的实验研究

外业像控及内业空三加密是摄影测量的基础工作,传统航摄资料在这方面有成熟的作法,而对数字航摄影像还没有制定相应的技术标准。本文通过分析DMC对外业像控及空三加密的技术要求,结合实验区分析DMC航摄资料特点,通过实验对DMC数字航摄资料的外业像控的布点方案、基线数量、点位位置等问题进行研究、分析和总结。